Technical Terms & Notation
付加体
A wedge of sediment and rock scraped off a subducting plate and piled up at the edge of the overriding plate.
Much of the basement of the Japanese Islands consists of accretionary prisms formed at ancient subduction zones.
日本列島の基盤の多くは、過去の沈み込み帯で形成された付加体からなる。
Related: subduction zone turbidite lithosphere
活性化エネルギー
A kinetic parameter describing how strongly the rate of a reaction or thermally activated process depends on temperature, commonly obtained from the Arrhenius equation.
The activation energy for superplastic deformation of coarse-grained FeAl alloys has been investigated.
粗大な結晶粒をもつFeAl合金の超塑性変形における活性化エネルギーが調べられた。
Related: homogeneous catalyst phase transition
アクチュエータ
A device that converts energy, such as electrical, hydraulic, or pneumatic energy, into mechanical motion.
A piezoelectric actuator was used to achieve nanometer-scale positioning.
ナノメートルスケールの位置決めを実現するために、圧電アクチュエータを用いた。
Related: feedback control degree of freedom inverse kinematics
積層造形（付加製造）
A process that builds three-dimensional objects layer by layer from digital data, commonly known as 3D printing.
Additive manufacturing enables the production of complex lattice structures that cannot be machined.
積層造形により、機械加工では製作できない複雑な格子構造を製造することが可能になる。
Related: CNC machining residual stress heat treatment
隣接行列
A square matrix used to represent a graph, in which each element indicates whether a pair of vertices is connected by an edge.
For dense graphs, an adjacency matrix allows edge queries in constant time.
密なグラフでは、隣接行列を用いると辺の有無を定数時間で調べることができる。
Related: breadth-first search Dijkstra's algorithm hash table
扇状地
A fan-shaped deposit of sediment formed where a steep mountain stream flows out onto a flat plain and slows down.
The city is built on an alluvial fan, where groundwater is abundant but debris flows pose a risk.
この都市は扇状地の上に築かれており、地下水は豊富だが土石流の危険がある。
Related: river terrace lahar sedimentary facies
A/D変換器（アナログ–デジタル変換器）
A device that converts a continuous analog signal, such as a voltage, into discrete digital values.
A 12-bit analog-to-digital converter samples the sensor voltage at 10 kHz.
12ビットのA/D変換器が、センサ電圧を10 kHzでサンプリングする。
Related: sampling theorem microcontroller signal-to-noise ratio
アンテナ
A device that converts electrical signals into electromagnetic waves for transmission, or electromagnetic waves into electrical signals for reception.
A half-wave dipole antenna was designed for the 2.4 GHz band.
2.4 GHz帯用の半波長ダイポールアンテナを設計した。
帯水層
A layer of permeable rock or sediment that can store and transmit enough groundwater to supply wells or springs.
The confined aquifer beneath the plain is recharged mainly in the surrounding mountains.
この平野の下にある被圧帯水層は、主に周囲の山地で涵養されている。
Related: groundwater recharge hydraulic conductivity diagenesis
アセノスフェア
The weak, partly ductile layer of the upper mantle beneath the lithosphere, on which the plates move.
Seismic waves travel more slowly through the asthenosphere, suggesting the presence of a small amount of partial melt.
地震波はアセノスフェア内をより遅く伝わることから、少量の部分溶融物が存在することが示唆される。
Related: lithosphere partial melting mantle convection
不斉反応
A reaction that produces one enantiomer of a chiral product in excess over the other, usually with a chiral catalyst.
A chiral phosphoric acid catalyst promoted the asymmetric reaction with excellent enantioselectivity.
キラルリン酸触媒により、その不斉反応は優れたエナンチオ選択性で進行した。
Related: enantiomer stereoselectivity organocatalyst optical purity
原子効率
The percentage of the total stoichiometric mass of reactants incorporated into the desired product, calculated from the balanced reaction equation.
The atom economy concept is one of the earliest recognitions of the green and sustainable aspects of organic synthesis.
原子効率の概念は、有機合成における環境配慮と持続可能性の重要性を早くから認識した考え方の一つである。
Related: cross-dehydrogenative coupling homogeneous catalyst
注意機構（アテンション機構）
A neural network component that assigns different weights to parts of the input so that the model focuses on the most relevant information.
The Transformer architecture relies entirely on the attention mechanism instead of recurrence.
Transformerアーキテクチャは、再帰構造の代わりに注意機構のみに基づいている。
Related: large language model natural language processing backpropagation
誤差逆伝播法
An algorithm for training neural networks that computes the gradient of the loss with respect to each weight by applying the chain rule backward through the layers.
Backpropagation made it practical to train neural networks with many hidden layers.
誤差逆伝播法によって、多数の隠れ層をもつニューラルネットワークの学習が実用的になった。
Related: gradient descent loss function convolutional neural network
バンドギャップ
The energy difference between the top of the valence band and the bottom of the conduction band in a semiconductor or insulator.
Gallium nitride has a wide band gap of about 3.4 eV, making it suitable for blue LEDs.
窒化ガリウムは約3.4 eVの広いバンドギャップをもつため、青色LEDに適している。
Related: p–n junction doping photovoltaic cell
帯域幅
The range of frequencies over which a system operates effectively, or the maximum data rate of a communication channel.
The amplifier has a bandwidth of 10 MHz, defined by its −3 dB points.
この増幅器の帯域幅は、−3 dB点で定義して10 MHzである。
Related: frequency response modulation low-pass filter
曲げモーメント
The internal moment in a beam that results from external loads and causes the beam to bend.
The maximum bending moment occurs at the center of a simply supported beam under a uniform load.
等分布荷重を受ける単純支持はりでは、最大曲げモーメントは中央で生じる。
Related: shear force second moment of area buckling
ベルヌーイの定理（ベルヌーイの式）
An equation stating that, for steady inviscid incompressible flow along a streamline, the sum of pressure, kinetic energy, and potential energy per unit volume is constant.
The flow rate through the venturi meter was calculated using Bernoulli's equation.
ベンチュリ管を流れる流量は、ベルヌーイの式を用いて計算した。
Related: viscosity head loss cavitation
ビッグオー記法（O記法）
A mathematical notation that describes an upper bound on the growth rate of a function, commonly used to express algorithm complexity.
In big-O notation, binary search on a sorted array runs in O(log n) time.
O記法で表すと、ソート済み配列に対する二分探索はO(log n)時間で動作する。
Related: time complexity NP-complete hash table
二分探索木
A tree data structure in which each node's left subtree contains smaller keys and its right subtree contains larger keys.
Searching a balanced binary search tree takes O(log n) time.
平衡した二分探索木の探索にはO(log n)の時間がかかる。
Related: hash table priority queue divide and conquer
生物地球化学的循環
The pathway by which a chemical element, such as carbon or nitrogen, moves between living organisms, the atmosphere, the ocean, and rocks.
Human activities have significantly altered the global biogeochemical cycles of carbon and nitrogen.
人間活動は、炭素と窒素の地球規模の生物地球化学的循環を大きく変化させてきた。
Related: chemical weathering eutrophication radiative forcing
バイポーラトランジスタ
A transistor made of three doped semiconductor regions in which a small base current controls a larger collector current.
In the common-emitter configuration, the bipolar junction transistor provides a current gain of about 100.
エミッタ接地構成では、バイポーラトランジスタは約100の電流増幅率を示す。
Related: MOSFET p–n junction gain
境界層
The thin layer of fluid close to a solid surface in which the flow velocity changes from zero at the wall to the free-stream velocity.
Boundary layer separation on the wing surface leads to a sudden loss of lift.
翼面での境界層はく離は、揚力の急激な低下を引き起こす。
Related: viscosity drag coefficient laminar flow
汽水
Water that is saltier than fresh water but less salty than seawater, typically found where rivers meet the sea.
Lake Shinji contains brackish water, whose salinity changes as seawater flows in through Lake Nakaumi.
宍道湖の水は汽水であり、中海を通じて海水が流入することで塩分が変化する。
幅優先探索
A graph traversal algorithm that visits all vertices at the current distance from the start before moving to vertices farther away.
Breadth-first search finds the shortest path in an unweighted graph.
幅優先探索は、重みなしグラフにおける最短経路を求める。
Related: adjacency matrix Dijkstra's algorithm priority queue
座屈
A sudden sideways failure of a slender structural member under compressive load at a stress below the material's compressive strength.
The critical buckling load of the column was calculated using the Euler formula.
柱の座屈荷重は、オイラーの式を用いて計算した。
Related: second moment of area factor of safety bending moment
バッファオーバーフロー
A software error in which a program writes more data into a memory buffer than it can hold, overwriting adjacent memory and possibly allowing attacks.
The vulnerability was caused by a buffer overflow in the image-parsing library.
この脆弱性は、画像解析ライブラリにおけるバッファオーバーフローによって引き起こされた。
Related: firewall cache memory unit testing
キャッシュメモリ
A small, fast memory located close to the processor that stores copies of frequently used data to reduce access time.
Optimizing the data layout reduced misses in the cache memory and halved the execution time.
データ配置を最適化したことでキャッシュメモリでのミスが減少し、実行時間が半分になった。
Related: latency context switch virtual machine
カルデラ
A large, basin-shaped depression formed when the ground collapses into an emptied magma chamber after a large eruption.
The Aso caldera, about 25 km across, was formed by four large pyroclastic eruptions.
直径約25 kmの阿蘇カルデラは、4回の大規模な火砕噴火によって形成された。
Related: magma chamber pyroclastic flow pluton
静電容量（キャパシタンス）
The ability of a component or system to store electric charge, defined as the ratio of stored charge to the applied voltage.
The capacitance of the touch sensor changes when a finger approaches the electrode.
指が電極に近づくと、タッチセンサの静電容量が変化する。
Related: permittivity time constant inductance
カルノーサイクル
An idealized reversible thermodynamic cycle consisting of two isothermal and two adiabatic processes, which gives the maximum possible efficiency between two temperatures.
No real engine can exceed the efficiency of the Carnot cycle operating between the same temperatures.
同じ温度間で作動する実際の熱機関は、カルノーサイクルの効率を超えることはできない。
Related: thermal efficiency entropy coefficient of performance
キャビテーション
The formation and violent collapse of vapor bubbles in a liquid where the local pressure falls below the vapor pressure, which can damage pumps and propellers.
Cavitation erosion was observed on the impeller blades of the pump.
ポンプの羽根車にキャビテーションによる壊食が観察された。
Related: Bernoulli's equation head loss computational fluid dynamics
化学的風化
The breakdown of rocks and minerals through chemical reactions with water, oxygen, and acids at or near the Earth's surface.
Chemical weathering of silicate rocks consumes atmospheric CO₂ over geological time scales.
ケイ酸塩岩の化学的風化は、地質学的時間スケールで大気中のCO₂を消費する。
Related: biogeochemical cycle slope failure diagenesis
化学選択性
The preferential reaction of a reagent with one functional group in the presence of other functional groups.
The thiolate-catalyzed Tishchenko reaction has shown high chemoselectivity for the formation of esters bearing aromatic groups in both the acyl and alcohol-derived portions.
チオラート触媒によるティシチェンコ反応は、アシル部分とアルコール由来の部分の両方に芳香族基をもつエステルの生成に対して高い化学選択性を示した。
Related: stereoselectivity nucleophile
CMOS（相補型金属酸化膜半導体）
A technology that uses complementary pairs of p-type and n-type MOSFETs to build logic circuits with very low static power consumption.
Most modern microprocessors and image sensors are fabricated using CMOS technology.
現代のマイクロプロセッサやイメージセンサの多くは、CMOS技術を用いて製造されている。
Related: MOSFET logic gate integrated circuit
CNC加工（数値制御加工）
A manufacturing process in which machine tools such as mills and lathes are controlled by a computer program to cut material precisely.
The prototype parts were produced by five-axis CNC machining.
試作部品は5軸CNC加工によって製作された。
Related: cutting speed additive manufacturing dimensional tolerance
摩擦係数
The ratio of the friction force between two surfaces to the normal force pressing them together.
The coating reduced the coefficient of friction of the sliding surface to 0.05.
このコーティングによって、しゅう動面の摩擦係数は0.05に低下した。
Related: viscosity gear ratio cutting speed
成績係数
The ratio of the useful heating or cooling provided by a heat pump or refrigerator to the work input required.
The heat pump has a coefficient of performance of 4, meaning it delivers four units of heat per unit of electricity.
このヒートポンプの成績係数は4であり、電力1単位あたり4単位の熱を供給することを意味する。
Related: Carnot cycle thermal efficiency enthalpy
コンパイラ
A program that translates source code written in a high-level programming language into machine code or another lower-level form.
The compiler optimizes loops to make the generated code run faster.
コンパイラはループを最適化し、生成されるコードをより高速に動作させる。
Related: object-oriented programming unit testing time complexity
数値流体力学
The use of numerical methods and computers to solve the equations of fluid motion and simulate flow, heat transfer, and related phenomena.
Computational fluid dynamics was used to optimize the shape of the cooling duct.
冷却ダクトの形状を最適化するために、数値流体力学を用いた。
Related: finite element method turbulent flow drag coefficient
混同行列
A table that summarizes the performance of a classification model by showing counts of correct and incorrect predictions for each class.
The confusion matrix shows that most errors occurred between the classes "cat" and "fox".
混同行列から、誤りの大半が「猫」と「キツネ」のクラス間で生じたことがわかる。
コンテキストスイッチ
The process by which an operating system saves the state of a running process and restores the state of another so that the CPU can switch between them.
Frequent context switches increase overhead and reduce overall performance.
頻繁なコンテキストスイッチはオーバーヘッドを増大させ、全体の性能を低下させる。
Related: deadlock virtual machine cache memory
畳み込みニューラルネットワーク
A deep neural network that uses convolutional layers with small filters to detect local patterns, widely used for image recognition.
A convolutional neural network was trained to detect cracks in concrete surface images.
コンクリート表面画像のひび割れを検出するために、畳み込みニューラルネットワークを学習させた。
Related: backpropagation feature extraction supervised learning
共有結合
A chemical bond in which two atoms share one or more pairs of electrons.
These polymers exhibit dynamic features originating in the reversibility of dynamic covalent bonds.
これらのポリマーは、動的共有結合の可逆性に由来する動的な性質を示す。
Related: hydrogen bond homolysis intermolecular interactions
クリープ
The slow, time-dependent plastic deformation of a material under constant stress, especially at high temperature.
Turbine blades must resist creep at temperatures above 1000 °C.
タービンブレードは、1000 °Cを超える温度でクリープに耐えなければならない。
脱水素型クロスカップリング
A reaction that joins two C–H (or X–H) partners directly by removing hydrogen, forming a new bond without pre-functionalized starting materials.
Cross-dehydrogenative coupling (CDC) reactions involving C–H bond activation are powerful tools for C–C bond formation and are highly significant from the perspective of atom economy.
C–H結合活性化を伴う脱水素型クロスカップリング（CDC）反応は、C–C結合形成のための強力な手法であり、原子効率の観点からも非常に重要である。
Related: atom economy hydrogen atom transfer transition metal catalyst
交差検証
A method for evaluating a model by repeatedly splitting the data into training and validation sets and averaging the results.
Model performance was evaluated by five-fold cross-validation.
モデルの性能は5分割交差検証によって評価した。
暗号学的ハッシュ関数
A function that maps data of any size to a fixed-length value in a way that is practically impossible to reverse or to find two inputs with the same output.
Passwords should be stored as outputs of a cryptographic hash function rather than as plain text.
パスワードは平文ではなく、暗号学的ハッシュ関数の出力として保存すべきである。
Related: digital signature hash table public-key cryptography
切削速度
The relative speed between the cutting tool and the workpiece surface in machining, usually expressed in meters per minute.
Increasing the cutting speed improved the surface finish but shortened tool life.
切削速度を上げると表面粗さは改善したが、工具寿命は短くなった。
Related: CNC machining coefficient of friction residual stress
減衰比
A dimensionless measure of how quickly vibrations in a system decay, defined as the ratio of actual damping to critical damping.
A damping ratio of 0.7 gives a fast response with little overshoot.
減衰比0.7では、オーバーシュートの少ない速い応答が得られる。
Related: natural frequency resonance PID controller
データベースの正規化
The process of organizing tables in a relational database to reduce data redundancy and prevent update anomalies.
After database normalization, each department name is stored only once.
データベースの正規化を行った後は、各学科名は一度だけ保存される。
Related: relational database hash table version control
DC–DCコンバータ
A power electronic circuit that converts a direct-current voltage from one level to another, usually by high-frequency switching.
A buck DC–DC converter steps the 12 V battery voltage down to 5 V with 95% efficiency.
降圧型DC–DCコンバータは、12 Vのバッテリ電圧を95%の効率で5 Vに下げる。
Related: pulse-width modulation MOSFET inductance
デッドロック
A situation in which two or more processes cannot continue because each is waiting for a resource held by another.
The system froze because of a deadlock between two threads competing for the same locks.
同じロックを取り合う2つのスレッド間でデッドロックが発生したため、システムが停止した。
自由度
The number of independent coordinates needed to fully describe the position or motion of a mechanical system.
The industrial robot arm has six degrees of freedom.
この産業用ロボットアームは6自由度をもつ。
Related: inverse kinematics natural frequency actuator
続成作用
The physical and chemical changes, such as compaction and cementation, that turn loose sediment into sedimentary rock after deposition.
During diagenesis, porosity decreases as grains are compacted and cemented by calcite.
続成作用の過程で、粒子が圧密され方解石によって膠結されるにつれて、間隙率は低下する。
Related: sedimentary facies metamorphic facies aquifer
数値標高モデル
A digital representation of the ground surface as a grid of elevation values, used for terrain analysis and mapping.
We used a 5-m digital elevation model derived from airborne LiDAR to map landslide scarps.
航空機LiDARから作成した5 mメッシュの数値標高モデルを用いて、地すべり滑落崖を図化した。
Related: slope failure alluvial fan river terrace
デジタル署名
A cryptographic technique that uses a private key to sign data so that anyone with the public key can verify its origin and integrity.
Software updates are protected by a digital signature to ensure that they have not been tampered with.
ソフトウェアの更新は、改ざんされていないことを保証するためにデジタル署名で保護されている。
Related: public-key cryptography cryptographic hash function two-factor authentication
ダイクストラ法
An algorithm that finds the shortest paths from a source vertex to all other vertices in a graph with non-negative edge weights.
Dijkstra's algorithm is widely used in route-planning systems for car navigation.
ダイクストラ法は、カーナビゲーションの経路探索システムで広く用いられている。
Related: breadth-first search priority queue greedy algorithm
寸法公差
The permitted range of variation in a dimension of a manufactured part, specified by upper and lower limits.
The shaft diameter must be within a dimensional tolerance of ±0.01 mm.
シャフトの直径は、±0.01 mmの寸法公差内に収まっていなければならない。
Related: CNC machining factor of safety cutting speed
双極子
A pair of equal and opposite charges (δ+ and δ−) separated by a distance; its strength is the dipole moment (μ).
Dimers in microtubules possess a dipole moment with components along three axes.
微小管中の二量体は、三つの軸に沿った成分をもつ双極子モーメントを有する。
Related: polar solvent intermolecular interactions electrostatic interaction
不均化
A redox reaction in which one species is simultaneously oxidized and reduced to give two different products.
Hydrogen peroxide undergoes disproportionation to form water and oxygen.
過酸化水素は不均化して水と酸素を生成する。
分散システム
A system in which multiple networked computers coordinate their actions and appear to users as a single coherent system.
The data are processed by a distributed system consisting of 100 servers.
データは100台のサーバからなる分散システムによって処理される。
Related: load balancing deadlock virtual machine
分割統治法
An algorithm design strategy that splits a problem into smaller independent subproblems, solves them recursively, and combines the results.
Merge sort is a classic example of the divide and conquer approach.
マージソートは分割統治法の代表的な例である。
Related: dynamic programming time complexity binary search tree
ドーピング
The intentional addition of small amounts of impurity atoms to a semiconductor to change its electrical conductivity.
Doping silicon with phosphorus produces an n-type semiconductor.
シリコンにリンをドーピングすると、n型半導体が得られる。
Related: p–n junction band gap MOSFET
抗力係数
A dimensionless number that quantifies the drag force on a body moving through a fluid, relative to dynamic pressure and reference area.
The streamlined body reduced the drag coefficient from 0.45 to 0.28.
流線形のボディによって、抗力係数は0.45から0.28に低減した。
Related: boundary layer turbulent flow computational fluid dynamics
動的計画法
An algorithm design technique that solves a problem by breaking it into overlapping subproblems and storing their solutions to avoid recomputation.
We applied dynamic programming to compute the edit distance between two DNA sequences.
2つのDNA配列間の編集距離を計算するために、動的計画法を適用した。
Related: divide and conquer greedy algorithm time complexity
エルニーニョ・南方振動
A recurring climate pattern involving changes in sea surface temperature in the tropical Pacific and in atmospheric pressure across the Pacific.
The El Niño–Southern Oscillation strongly influences summer temperatures and rainfall in Japan.
エルニーニョ・南方振動は、日本の夏の気温や降水量に大きな影響を及ぼす。
Related: radiative forcing glacial–interglacial cycle oxygen isotope ratio
電気分解
The use of electric current to drive a non-spontaneous chemical reaction, such as splitting water into H2 and O2.
Hydrogen was produced by the electrolysis of water using a nickel-based electrode.
ニッケル系電極を用いた水の電気分解によって水素を製造した。
Related: oxidation reduction redox potential
電磁誘導
The generation of an electromotive force in a conductor when the magnetic flux through it changes, as described by Faraday's law.
Wireless chargers transfer energy to smartphones by electromagnetic induction.
ワイヤレス充電器は、電磁誘導によってスマートフォンにエネルギーを伝送する。
Related: transformer inductance magnetic flux density
電磁波
A wave of coupled oscillating electric and magnetic fields that propagates through space at the speed of light.
Microwaves are electromagnetic waves with wavelengths between about 1 mm and 1 m.
マイクロ波は、波長が約1 mmから1 mの電磁波である。
Related: Maxwell's equations antenna permittivity
電子受容体
A molecule or group that receives electrons from another species; it is reduced in the process.
Photoinduced charge-transfer polymerization of styrene (St) with an electron acceptor as the initiator was investigated.
電子受容体を開始剤として用いたスチレン（St）の光誘起電荷移動重合を調べた。
電子供与体
A molecule or group that gives electrons to another species; it is oxidized in the process.
Polymerization reactions with organic electron donors (OEDs) as initiators are presented herein.
本稿では、有機電子供与体（OED）を開始剤とする重合反応を紹介する。
Related: electron acceptor oxidation single electron transfer
求電子剤
An electron-poor species that accepts an electron pair from a nucleophile to form a new bond.
Herein, we focus on the first step of this process, electrophile sensing.
本稿では、この過程の最初の段階である求電子剤の感知に焦点を当てる。
静電相互作用
The attraction between opposite charges, or repulsion between like charges, described by Coulomb's law.
The aggregation of the colloidal particles is mainly controlled by electrostatic interaction between their charged surfaces.
コロイド粒子の凝集は、主にそれらの帯電した表面間の静電相互作用によって支配される。
鏡像異性体（エナンチオマー）
One of a pair of molecules that are non-superimposable mirror images of each other, like left and right hands.
This review summarizes cases in which the enantiomer migration order (EMO) is reversed in chiral capillary electrophoresis.
本総説では、キラルキャピラリー電気泳動において鏡像異性体の泳動順序（EMO）が逆転する例をまとめる。
Related: racemate optical purity stereoisomer
エンタルピー
A thermodynamic property equal to the internal energy of a system plus the product of its pressure and volume, useful for analyzing flow processes.
The enthalpy of the steam at the turbine inlet was obtained from the steam tables.
タービン入口における蒸気のエンタルピーは、蒸気表から求めた。
Related: entropy heat exchanger thermal efficiency
エントロピー
A thermodynamic property that measures the degree of disorder of a system or the unavailability of its energy to do work.
According to the second law of thermodynamics, the entropy of an isolated system never decreases.
熱力学第二法則によれば、孤立系のエントロピーは決して減少しない。
Related: enthalpy Carnot cycle thermal efficiency
富栄養化
The excessive enrichment of a water body with nutrients such as nitrogen and phosphorus, leading to algal blooms and oxygen depletion.
Eutrophication caused by agricultural runoff has resulted in frequent algal blooms in the lake.
農地からの流出水による富栄養化によって、この湖ではアオコが頻繁に発生している。
Related: brackish water biogeochemical cycle groundwater recharge
安全率
The ratio of the strength of a component to the maximum stress expected in service, providing a margin against failure.
The bolt was designed with a factor of safety of 3 against yielding.
このボルトは、降伏に対して安全率3で設計された。
Related: yield strength fatigue failure buckling
疲労破壊
The fracture of a material caused by repeated cyclic loading at stress levels below its static strength.
Fatigue failure initiated at a small surface scratch on the crankshaft.
疲労破壊は、クランク軸表面の小さな傷から発生した。
Related: stress concentration fracture toughness residual stress
特徴抽出
The process of transforming raw data into a set of informative numerical features that can be used by a learning algorithm.
Mel-frequency cepstral coefficients were used for feature extraction from speech signals.
音声信号からの特徴抽出には、メル周波数ケプストラム係数を用いた。
Related: convolutional neural network principal component analysis supervised learning
フィードバック制御
A control method in which the output of a system is measured and compared with a desired value, and the difference is used to adjust the input.
Feedback control keeps the motor speed constant even when the load changes.
フィードバック制御により、負荷が変化してもモータの回転速度は一定に保たれる。
Related: PID controller transfer function actuator
有限要素法
A numerical technique that divides a structure into many small elements to approximate solutions of physical problems such as stress, heat, or vibration.
The stress distribution in the bracket was analyzed by the finite element method.
ブラケットの応力分布を有限要素法によって解析した。
Related: stress concentration computational fluid dynamics natural frequency
ファイアウォール
A network security system that monitors and controls incoming and outgoing traffic according to predefined rules.
The firewall blocks all incoming connections except those on port 443.
ファイアウォールは、ポート443以外へのすべての着信接続を遮断している。
Related: protocol stack buffer overflow two-factor authentication
フリップフロップ
A bistable digital circuit that stores one bit of information and changes state in response to a clock or control signal.
The shift register consists of eight D flip-flops connected in series.
このシフトレジスタは、直列に接続された8個のDフリップフロップで構成されている。
Related: logic gate microcontroller integrated circuit
発震機構（メカニズム解）
A description of the fault orientation and slip direction of an earthquake, usually shown as a "beach ball" diagram.
The focal mechanism indicates reverse faulting with a northwest–southeast compression axis.
この発震機構は、北西–南東方向に圧縮軸をもつ逆断層型であることを示している。
Related: transform fault hypocenter moment magnitude
フーリエ変換
A mathematical transformation that decomposes a signal into its frequency components.
The vibration signal was analyzed using the fast Fourier transform to identify its dominant frequencies.
振動信号を高速フーリエ変換で解析し、その主要な周波数を特定した。
Related: sampling theorem frequency response low-pass filter
結晶分化作用
The process by which minerals crystallize from cooling magma and are separated from it, changing the composition of the remaining melt.
Fractional crystallization of basaltic magma can produce andesitic and dacitic melts.
玄武岩質マグマの結晶分化作用によって、安山岩質やデイサイト質のメルトが生じうる。
Related: magma chamber partial melting pluton
破壊靱性
A material property that describes its resistance to the growth of a crack, usually expressed as the critical stress intensity factor K_IC.
Ceramics have high hardness but low fracture toughness compared with metals.
セラミックスは金属と比べて硬さは高いが、破壊靱性は低い。
Related: stress concentration fatigue failure stress–strain curve
周波数応答
The measure of how the output amplitude and phase of a system vary with the frequency of a sinusoidal input.
The frequency response of the microphone is flat from 50 Hz to 15 kHz.
このマイクロホンの周波数応答は、50 Hzから15 kHzまで平坦である。
Related: bandwidth low-pass filter Fourier transform
利得（ゲイン）
The ratio of the output to the input of an amplifier or system, often expressed in decibels.
The amplifier provides a voltage gain of 40 dB over the audio frequency range.
この増幅器は、可聴周波数帯域で40 dBの電圧利得をもつ。
Related: operational amplifier frequency response signal-to-noise ratio
ギア比（歯車比）
The ratio of the number of teeth (or rotational speeds) of two meshing gears, which determines the change in speed and torque.
A gear ratio of 4:1 reduces the output speed and increases the torque by a factor of four.
4:1のギア比は、出力速度を4分の1にし、トルクを4倍にする。
Related: torsion coefficient of friction actuator
氷期–間氷期サイクル
The repeated alternation between cold glacial periods with large ice sheets and warmer interglacial periods, paced by changes in Earth's orbit.
During the last 800,000 years, glacial–interglacial cycles have occurred approximately every 100,000 years.
過去80万年間、氷期–間氷期サイクルはおよそ10万年ごとに起こってきた。
勾配降下法
An optimization algorithm that repeatedly updates parameters in the direction opposite to the gradient of the loss function to find its minimum.
The network weights were updated by stochastic gradient descent with a learning rate of 0.01.
ネットワークの重みは、学習率0.01の確率的勾配降下法によって更新された。
Related: loss function backpropagation regularization
貪欲法（グリーディ法）
An algorithm that builds a solution step by step, always choosing the option that looks best at the moment.
A greedy algorithm does not always find the optimal solution, but it is often fast and simple to implement.
貪欲法は常に最適解を見つけるとは限らないが、多くの場合高速で実装も簡単である。
Related: dynamic programming NP-complete Dijkstra's algorithm
地下水涵養
The process by which water from precipitation or surface water infiltrates the ground and replenishes an aquifer.
Urbanization reduces groundwater recharge because paved surfaces prevent rainwater from infiltrating the soil.
都市化によって舗装面が雨水の土壌への浸透を妨げるため、地下水涵養は減少する。
Related: aquifer hydraulic conductivity brackish water
半減期
The time required for half of the atoms of a radioactive isotope in a sample to decay.
Carbon-14 has a half-life of about 5,730 years, which limits radiocarbon dating to roughly the last 50,000 years.
炭素14の半減期は約5,730年であるため、放射性炭素年代測定はおよそ過去5万年に限られる。
Related: radiometric dating zircon U–Pb dating oxygen isotope ratio
ハッシュテーブル
A data structure that stores key–value pairs and uses a hash function to compute the location of each key, allowing fast lookup.
Using a hash table, the average time to search for a word in the dictionary becomes O(1).
ハッシュテーブルを用いると、辞書内の単語を探索する平均時間はO(1)になる。
Related: cryptographic hash function binary search tree big-O notation
損失水頭
The loss of mechanical energy in a flowing fluid, expressed as an equivalent height of fluid, caused by friction and fittings such as bends and valves.
The head loss in the pipeline was estimated using the Darcy–Weisbach equation.
配管の損失水頭は、ダルシー・ワイスバッハの式を用いて推定した。
Related: Bernoulli's equation viscosity turbulent flow
熱交換器
A device that transfers heat between two or more fluids at different temperatures without mixing them.
A plate heat exchanger was used to recover waste heat from the exhaust water.
排水から廃熱を回収するために、プレート式熱交換器を用いた。
Related: heat transfer coefficient thermal conductivity enthalpy
熱伝達率
A coefficient that relates the convective heat flux between a surface and a fluid to their temperature difference.
The heat transfer coefficient increased with the flow velocity of the cooling water.
熱伝達率は、冷却水の流速とともに増加した。
熱処理
A controlled process of heating and cooling a metal to change its microstructure and mechanical properties, such as hardness and toughness.
Quenching and tempering is a common heat treatment for improving the toughness of steel.
焼入れ焼戻しは、鋼の靱性を向上させるための一般的な熱処理である。
Related: yield strength residual stress creep
不均一触媒
A catalyst in a different phase from the reactants, typically a solid surface in contact with gases or liquids.
Numerous methods are now available for the synthesis of a large variety of heterogeneous molecular catalysts.
現在では、多種多様な不均一系分子触媒を合成するための数多くの方法が利用可能である。
Related: homogeneous catalyst supported catalyst
均一触媒
A catalyst that is in the same phase as the reactants, usually dissolved in the reaction solution.
Aryl- and alkyl-substituted tertiary phosphines are among the most common ligands used in homogeneous catalysts.
アリール基およびアルキル基で置換された三級ホスフィンは、均一触媒に用いられる最も一般的な配位子の一つである。
Related: heterogeneous catalyst transition metal catalyst organocatalyst
ホモリシス（均等開裂）
The breaking of a covalent bond in which each atom keeps one electron, producing two radicals.
The rate constants for the homolysis of C–C and C–N bonds in nitro compounds were estimated using a QSPR approach.
QSPR法を用いて、ニトロ化合物中のC–C結合およびC–N結合のホモリシスの速度定数を推定した。
Related: covalent bond radical chain mechanism hydrogen atom transfer
透水係数
A measure of how easily water can flow through a porous material such as soil or rock under a hydraulic gradient.
Gravel has a much higher hydraulic conductivity than clay, which allows groundwater to move rapidly.
礫は粘土よりもはるかに高い透水係数をもつため、地下水は速く移動することができる。
Related: aquifer groundwater recharge liquefaction
水素原子移動
The concerted transfer of a hydrogen atom—a proton and an electron—from a donor site to an acceptor site, either within one molecule or between species.
Hydrogen-atom transfer (HAT) is of key importance for several catalytic and biological processes, and provides an elegant route to C–H activation.
水素原子移動（HAT）はいくつかの触媒過程や生体内過程で極めて重要であり、C–H結合の活性化を実現する巧妙な手法となる。
Related: single electron transfer radical chain mechanism homolysis
水素結合
An attractive interaction involving a hydrogen atom bonded to a more electronegative atom and an electron-rich atom or group in the same or another molecule; common examples involve O–H or N–H donors.
In moderately strong hydrogen bonds, hydrogen bond formation increases the anharmonicity constant of the high-frequency stretching vibration.
中程度の強さの水素結合では、水素結合の形成によって高振動数の伸縮振動の非調和定数が増大する。
加水分解
The breaking of a chemical bond by reaction with water.
Acid-catalyzed hydrolysis of an ester produces a carboxylic acid and an alcohol.
エステルの酸触媒加水分解によって、カルボン酸とアルコールが生成する。
震源
The point inside the Earth where an earthquake rupture starts; the point on the surface directly above it is the epicenter.
The hypocenter was located at a depth of 10 km, so strong shaking was felt over a wide area.
震源は深さ10 kmに位置していたため、広い範囲で強い揺れが感じられた。
Related: P wave S wave moment magnitude
インピーダンス
The total opposition that a circuit presents to alternating current, combining resistance and reactance, expressed as a complex number.
The input impedance of the amplifier should be much higher than the output impedance of the sensor.
増幅器の入力インピーダンスは、センサの出力インピーダンスよりも十分に高くなければならない。
Related: phasor RLC circuit transmission line
示準化石
A fossil of an organism that lived for a short geological time but was widespread, used to date and correlate rock layers.
Ammonites are useful index fossils for correlating Jurassic and Cretaceous marine strata.
アンモナイトは、ジュラ紀および白亜紀の海成層を対比するのに有用な示準化石である。
Related: law of superposition radiometric dating sedimentary facies
インダクタンス
The property of an electrical conductor or coil by which a change in current induces a voltage that opposes the change.
The inductance of the coil increases with the square of the number of turns.
コイルのインダクタンスは、巻数の2乗に比例して増加する。
誘導電動機（誘導モータ）
An AC motor in which a rotating magnetic field in the stator induces currents in the rotor, producing torque.
Squirrel-cage induction motors are robust and widely used in pumps and fans.
かご形誘導電動機は頑丈であり、ポンプやファンに広く用いられている。
Related: three-phase power electromagnetic induction inverter
集積回路
An electronic circuit in which many components such as transistors, resistors, and capacitors are fabricated together on a single semiconductor chip.
The new integrated circuit contains more than ten billion transistors.
この新しい集積回路には100億個以上のトランジスタが含まれている。
Related: CMOS microcontroller MOSFET
分子間相互作用
Attractive or repulsive forces acting between neighboring molecules, such as hydrogen bonding, dipole–dipole and van der Waals forces.
Direct measurements of intermolecular interactions help explain why these crystals have such high melting points.
分子間相互作用を直接測定することは、これらの結晶がなぜこれほど高い融点をもつのかを説明する助けとなる。
Related: hydrogen bond electrostatic interaction dipole supramolecular assembly
項間交差
A non-radiative transition between electronic states of different spin, typically from an excited singlet (S1) to a triplet (T1).
The intersystem crossing rate from the singlet excited state to the triplet excited state of an organic molecule has been derived.
有機分子の一重項励起状態から三重項励起状態への項間交差速度が導出された。
Related: triplet state room-temperature phosphorescence quantum yield
逆運動学
The calculation of the joint angles of a robot or linkage that are needed to place its end-effector at a desired position and orientation.
Inverse kinematics was solved numerically to plan the motion of the robot arm.
ロボットアームの動作を計画するために、逆運動学を数値的に解いた。
Related: degree of freedom actuator feedback control
インバータ
A power electronic device that converts direct current into alternating current, often with adjustable frequency and voltage.
The inverter controls the motor speed by changing the output frequency.
インバータは、出力周波数を変えることでモータの回転速度を制御する。
アイソスタシー
The state of gravitational balance in which the Earth's crust floats on the denser mantle, rising or sinking as loads are added or removed.
Scandinavia is still rising due to isostasy following the melting of the ice sheet.
スカンジナビアは、氷床が融解した後のアイソスタシーによって現在も隆起し続けている。
Related: lithosphere glacial–interglacial cycle Moho discontinuity
k平均法（k-meansクラスタリング）
An unsupervised learning method that divides data into k groups by repeatedly assigning each point to the nearest cluster center and updating the centers.
The survey responses were grouped into four types using k-means clustering.
アンケートの回答を、k平均法を用いて4つのタイプに分類した。
Related: principal component analysis supervised learning feature extraction
キルヒホッフの電流則
The law stating that the algebraic sum of currents entering and leaving any node in an electric circuit is zero.
Applying Kirchhoff's current law at node A gives three equations for the unknown currents.
ノードAでキルヒホッフの電流則を適用すると、未知の電流に関する3つの式が得られる。
Related: Kirchhoff's voltage law Thévenin equivalent circuit voltage divider
キルヒホッフの電圧則
The law stating that the algebraic sum of all voltages around any closed loop in a circuit is zero.
Using Kirchhoff's voltage law, the voltage across the third resistor was found to be 2 V.
キルヒホッフの電圧則を用いて、3番目の抵抗にかかる電圧は2 Vと求められた。
火山泥流（ラハール）
A mudflow or debris flow of volcanic material mixed with water that flows rapidly down a volcano and river valleys.
Heavy rainfall on fresh ash deposits can trigger lahars long after an eruption has ended.
新しく堆積した火山灰に大雨が降ると、噴火が終わってから長い時間が経っても火山泥流が発生することがある。
Related: pyroclastic flow slope failure alluvial fan
層流
A smooth, orderly fluid flow in which the fluid moves in parallel layers with little mixing between them.
In the microchannel, laminar flow was maintained because of the low Reynolds number.
マイクロ流路内では、レイノルズ数が小さいため層流が維持された。
Related: turbulent flow Reynolds number boundary layer
大規模言語モデル
A very large neural network trained on huge amounts of text to predict the next word, capable of generating and understanding natural language.
Large language models can generate fluent text, but their outputs may contain factual errors.
大規模言語モデルは流暢な文章を生成できるが、その出力には事実誤認が含まれることがある。
Related: attention mechanism natural language processing supervised learning
レイテンシ（遅延時間）
The time delay between sending a request or signal and receiving the response, often measured in milliseconds.
Edge computing reduces latency by processing data close to where it is generated.
エッジコンピューティングは、データが生成される場所の近くで処理することでレイテンシを低減する。
Related: packet switching load balancing cache memory
地層累重の法則
The principle that, in undisturbed sedimentary layers, each layer is younger than the one below it and older than the one above it.
Applying the law of superposition, we inferred that the volcanic ash layer is younger than the underlying mudstone.
地層累重の法則を適用して、火山灰層はその下にある泥岩よりも新しいと推定した。
Related: unconformity index fossil radiometric dating
液状化
The loss of strength and stiffness of water-saturated loose sand during earthquake shaking, causing it to behave like a liquid.
Extensive liquefaction occurred on reclaimed land along Tokyo Bay during the 2011 earthquake.
2011年の地震の際、東京湾沿いの埋立地で大規模な液状化が発生した。
Related: S wave slope failure hydraulic conductivity
リソスフェア
The rigid outer shell of the Earth, consisting of the crust and the uppermost mantle, which is broken into tectonic plates.
The thickness of the oceanic lithosphere increases with the age of the seafloor.
海洋リソスフェアの厚さは、海底の年代とともに増加する。
Related: asthenosphere Moho discontinuity isostasy
負荷分散
The distribution of workloads or network requests across multiple servers to improve performance and reliability.
Load balancing prevents any single server from becoming a bottleneck during peak hours.
負荷分散によって、ピーク時に特定のサーバがボトルネックになるのを防ぐ。
Related: distributed system latency virtual machine
論理ゲート
An electronic circuit that performs a basic Boolean operation, such as AND, OR, or NOT, on one or more binary inputs.
Any digital circuit can be built from combinations of NAND logic gates.
どのようなデジタル回路も、NAND論理ゲートの組み合わせで構成できる。
Related: flip-flop CMOS integrated circuit
損失関数
A function that measures the difference between a model's predictions and the correct values; training aims to minimize it.
Cross-entropy was used as the loss function for the multi-class classification task.
多クラス分類タスクの損失関数として交差エントロピーを用いた。
ローパスフィルタ（低域通過フィルタ）
A filter that passes signals with frequencies below a cutoff frequency and attenuates higher-frequency signals.
A low-pass filter with a cutoff frequency of 50 Hz was applied to remove high-frequency noise.
高周波ノイズを除去するため、遮断周波数50 Hzのローパスフィルタを適用した。
Related: frequency response time constant signal-to-noise ratio
マグマだまり
A body of molten or partly molten rock stored in the crust beneath a volcano.
Ground deformation data suggest that the magma chamber lies about 8 km below the summit.
地殻変動データから、マグマだまりは山頂の下約8 kmにあると考えられる。
磁束密度
The amount of magnetic flux passing through a unit area perpendicular to the field, measured in teslas.
The magnetic flux density at the center of the MRI coil is 3 T.
MRIコイル中心部の磁束密度は3 Tである。
Related: electromagnetic induction inductance Maxwell's equations
マントル対流
The slow, solid-state circulation of the mantle driven by internal heat, which is thought to drive plate motion.
Numerical models of mantle convection help explain the formation of large igneous provinces.
マントル対流の数値モデルは、巨大火成岩岩石区の形成を説明するのに役立つ。
Related: mid-ocean ridge subduction zone asthenosphere
マクスウェル方程式
A set of four fundamental equations that describe how electric and magnetic fields are generated and how they interact.
Maxwell's equations predict that electromagnetic waves travel at the speed of light.
マクスウェル方程式は、電磁波が光速で伝わることを予測する。
Related: electromagnetic wave electromagnetic induction permittivity
変成相
A set of metamorphic mineral assemblages that forms under a particular range of pressure and temperature conditions.
The presence of glaucophane indicates that these rocks reached blueschist metamorphic facies conditions.
藍閃石が存在することは、これらの岩石が青色片岩相の変成条件に達したことを示している。
Related: subduction zone pluton diagenesis
マイクロコントローラ（マイコン）
A small computer on a single integrated circuit containing a processor, memory, and input/output peripherals, used to control embedded systems.
An Arduino microcontroller reads the temperature sensor and controls the fan.
Arduinoのマイクロコントローラが温度センサを読み取り、ファンを制御する。
Related: analog-to-digital converter pulse-width modulation integrated circuit
中央海嶺
A long underwater mountain chain where two plates move apart and new oceanic crust forms from rising magma.
Hydrothermal vents along the mid-ocean ridge support unique ecosystems that do not depend on sunlight.
中央海嶺沿いの熱水噴出孔は、太陽光に依存しない独特の生態系を支えている。
変調
The process of varying a property of a carrier wave, such as its amplitude, frequency, or phase, to encode information for transmission.
FM radio uses frequency modulation, which is less sensitive to noise than amplitude modulation.
FMラジオは周波数変調を用いており、振幅変調よりもノイズの影響を受けにくい。
Related: bandwidth antenna Fourier transform
モホロビチッチ不連続面（モホ面）
The boundary between the Earth's crust and mantle, marked by a sharp increase in seismic wave velocity.
Receiver function analysis revealed that the Moho discontinuity lies at a depth of about 30 km beneath the region.
レシーバー関数解析により、この地域の下ではモホ面が深さ約30 kmにあることが明らかになった。
Related: lithosphere seismic tomography P wave
モーメントマグニチュード
A measure of earthquake size based on seismic moment, which depends on fault area, average slip, and rock rigidity.
The 2011 Tohoku-oki earthquake had a moment magnitude of 9.0, making it the largest recorded earthquake in Japan.
2011年東北地方太平洋沖地震のモーメントマグニチュードは9.0であり、日本で観測史上最大の地震となった。
Related: hypocenter focal mechanism P wave
MOSFET（金属酸化膜半導体電界効果トランジスタ）
A field-effect transistor in which the current between source and drain is controlled by the voltage applied to an insulated gate.
Power MOSFETs are widely used as fast switches in DC–DC converters.
パワーMOSFETは、DC–DCコンバータの高速スイッチとして広く用いられている。
Related: CMOS bipolar junction transistor doping
多刺激応答
A change in a material’s properties in response to two or more different types of stimuli, such as temperature, light, or pH.
Liquid crystal elastomers with a reversible multistimuli response were developed as soft actuators.
可逆的な多刺激応答性をもつ液晶エラストマーが、ソフトアクチュエーターとして開発された。
Related: phase transition photoisomerization
固有振動数
The frequency at which a system tends to vibrate when disturbed and then left to oscillate freely without external forcing.
The natural frequency of the bridge was measured to avoid resonance with pedestrian footsteps.
歩行者の足踏みとの共振を避けるため、橋の固有振動数を測定した。
Related: resonance damping ratio degree of freedom
自然言語処理
The field of computer science concerned with enabling computers to analyze, understand, and generate human language.
Natural language processing techniques were used to extract technical terms from research papers.
研究論文から専門用語を抽出するために、自然言語処理の手法を用いた。
Related: large language model attention mechanism feature extraction
非極性溶媒
A solvent with little or no dipole moment, such as hexane or toluene; it dissolves nonpolar compounds well.
Nonpolar solvent separation is widely used in the petroleum, chemical and food industries, but traditional separation methods consume a great deal of energy.
非極性溶媒の分離は石油・化学・食品産業で広く用いられているが、従来の分離法は多くのエネルギーを消費する。
Related: polar solvent organic solvent
NP完全
Describing a decision problem in NP to which every other problem in NP can be reduced in polynomial time; no polynomial-time algorithm is known for such problems.
The traveling salesman problem in its decision form is NP-complete, so heuristic methods are often used for large instances.
判定問題としての巡回セールスマン問題はNP完全であるため、大規模な問題例にはヒューリスティック手法がよく用いられる。
求核剤
An electron-rich species that donates an electron pair to an electron-poor atom to form a new bond.
An efficient approach for the deprotection of esters has been developed using an ionic liquid as a nucleophile in the presence of a protic acid.
プロトン酸存在下でイオン液体を求核剤として用いる、効率的なエステルの脱保護法が開発された。
求核置換反応
A reaction in which a nucleophile replaces a leaving group at an electrophilic center, commonly a carbon atom; common mechanisms at saturated carbon include SN1 and SN2.
The factors determining the catalytic effect of supramolecular systems on nucleophilic substitution reactions are analyzed.
求核置換反応に対する超分子系の触媒効果を決定する要因を解析する。
Related: nucleophile electrophile hydrolysis
オブジェクト指向プログラミング
A programming paradigm that organizes software as objects combining data and the methods that operate on that data.
Object-oriented programming makes it easier to reuse and extend code through inheritance.
オブジェクト指向プログラミングでは、継承によってコードの再利用や拡張が容易になる。
Related: compiler unit testing version control
演算増幅器（オペアンプ）
A high-gain differential voltage amplifier with two inputs and one output, used with feedback to build amplifiers, filters, and other analog circuits.
An operational amplifier was used to amplify the weak signal from the strain gauge.
ひずみゲージからの微弱な信号を増幅するために、演算増幅器を用いた。
Related: gain low-pass filter Wheatstone bridge
光学純度
The ratio of a sample’s optical rotation to that of a pure enantiomer under identical measurement conditions, usually expressed as a percentage; it equals enantiomeric excess only when the rotation varies linearly with enantiomeric composition.
A new capillary electrophoresis method was established for the optical purity analysis of levodopa.
レボドパの光学純度分析のための新しいキャピラリー電気泳動法が確立された。
Related: enantiomer racemate asymmetric reaction
有機溶媒
A carbon-based liquid, such as ethanol, acetone or toluene, used to dissolve other substances.
The use of organic solvents as reaction media for enzymatic reactions provides numerous industrially attractive advantages compared to traditional aqueous reaction systems.
酵素反応の反応媒体として有機溶媒を用いることは、従来の水系反応系と比べて産業上魅力的な多くの利点をもたらす。
Related: polar solvent nonpolar solvent
有機分子触媒
A small, metal-free organic molecule (e.g., proline) that accelerates a chemical reaction.
A chiral organocatalyst was successfully entrapped by montmorillonite clay using the cation-exchange method.
陽イオン交換法を用いて、キラルな有機分子触媒をモンモリロナイト粘土に固定化することに成功した。
Related: asymmetric reaction transition metal catalyst homogeneous catalyst
過学習（過剰適合）
A situation in which a model learns the training data too closely, including its noise, and therefore performs poorly on new data.
To prevent overfitting, we applied dropout and stopped training when the validation loss began to increase.
過学習を防ぐため、ドロップアウトを適用し、検証損失が増加し始めた時点で学習を停止した。
Related: regularization cross-validation loss function
酸化
A process in which a substance loses electrons (or gains oxygen / loses hydrogen); its oxidation number increases.
The oxidation behavior of tantalum in steam was investigated in the temperature range of 600–1100 °C.
水蒸気中におけるタンタルの酸化挙動を600〜1100 °Cの温度範囲で調べた。
Related: reduction redox potential electron donor
酸素同位体比
The ratio of ¹⁸O to ¹⁶O in a sample, expressed as δ¹⁸O, used to reconstruct past temperatures and ice volume.
The benthic foraminiferal oxygen isotope ratio record shows a gradual cooling during the Cenozoic.
底生有孔虫の酸素同位体比の記録は、新生代を通じた緩やかな寒冷化を示している。
Related: glacial–interglacial cycle half-life radiative forcing
P波
A compressional seismic body wave that travels fastest and is therefore the first to arrive at a seismometer.
Earthquake early warning systems detect the P wave and issue alerts before the stronger S wave arrives.
緊急地震速報システムはP波を検知し、より強いS波が到達する前に警報を発する。
Related: S wave seismic tomography hypocenter
パケット交換
A method of data transmission in which a message is divided into small packets that are sent independently over a network and reassembled at the destination.
The Internet is based on packet switching, which uses network resources efficiently.
インターネットはパケット交換に基づいており、ネットワーク資源を効率的に利用する。
Related: protocol stack latency firewall
古地磁気
The record of the Earth's past magnetic field preserved in rocks by magnetic minerals aligned when the rock formed.
Studies of paleomagnetism indicate that southwest Japan rotated clockwise during the opening of the Sea of Japan.
古地磁気の研究は、日本海の拡大に伴って西南日本が時計回りに回転したことを示している。
Related: mid-ocean ridge lithosphere radiometric dating
部分溶融
The incomplete melting of a rock, in which minerals with lower melting points melt first to produce magma.
Basaltic magma is generated by partial melting of the upper mantle beneath mid-ocean ridges.
玄武岩質マグマは、中央海嶺の下で上部マントルが部分溶融することで生成される。
Related: asthenosphere fractional crystallization magma chamber
誘電率
A material property that describes how much electric field energy it can store, determining the capacitance of a capacitor filled with it.
Ceramic materials with high permittivity are used to make small, high-capacitance capacitors.
高い誘電率をもつセラミック材料は、小型で大容量のコンデンサの製造に用いられる。
Related: capacitance Maxwell's equations electromagnetic wave
相転移
A change of a material from one state or structure to another, such as solid to liquid or one crystal form to another, at a certain temperature or pressure.
The polymer film undergoes a phase transition from a crystalline to a liquid-crystalline state at 120 °C.
このポリマー薄膜は、120 °Cで結晶状態から液晶状態への相転移を起こす。
フェーザ
A complex number representing the amplitude and phase of a sinusoidal quantity, used to simplify the analysis of AC circuits.
Phasor diagrams show that the current lags the voltage by 30° in the inductive load.
フェーザ図から、誘導性負荷では電流が電圧より30°遅れていることがわかる。
Related: impedance power factor three-phase power
光異性化
A change of a molecule from one isomer to another caused by absorbing light, such as trans-to-cis switching.
In this study, we observed that the molecules exhibiting photoisomerization in solution are also photostable.
本研究では、溶液中で光異性化を示す分子が光安定性も備えていることを確認した。
Related: structural isomer stereoisomer quantum yield
太陽電池セル（光起電力セル）
A semiconductor device that converts light directly into electricity through the photovoltaic effect.
The conversion efficiency of the perovskite photovoltaic cell reached 25%.
このペロブスカイト太陽電池セルの変換効率は25%に達した。
Related: p–n junction band gap inverter
PID制御器
A feedback controller that computes its output from proportional, integral, and derivative terms of the error signal.
The PID controller gains were tuned by the Ziegler–Nichols method.
PID制御器のゲインは、ジーグラ・ニコルス法によって調整した。
深成岩体（プルトン）
A large body of intrusive igneous rock, such as granite, that crystallized from magma slowly at depth.
Zircon ages indicate that the granitic pluton was emplaced during the Late Cretaceous.
ジルコン年代から、この花崗岩質の深成岩体は後期白亜紀に定置したことが示される。
Related: magma chamber zircon U–Pb dating fractional crystallization
ポアソン比
The ratio of the lateral contraction strain to the longitudinal extension strain of a material under uniaxial stress.
Most metals have a Poisson's ratio of about 0.3.
ほとんどの金属のポアソン比は約0.3である。
Related: Young's modulus stress–strain curve torsion
極性溶媒
A solvent whose molecules have a significant dipole moment, such as water, methanol or DMSO; it can stabilize polar or charged species, with solubility depending on the solvent and solute.
The reaction proceeded much faster in polar solvents such as DMF than in toluene.
その反応はトルエン中よりもDMFのような極性溶媒中ではるかに速く進行した。
Related: nonpolar solvent dipole organic solvent
位置異性体
Structural isomers that differ only in the position of a functional group or double bond on the same carbon skeleton.
A new on-tissue reagent enables mass spectrometry imaging of lipid C=C position isomers in biological tissues.
新しい組織上反応試薬により、生体組織中の脂質のC=C位置異性体を質量分析イメージングで可視化できるようになった。
Related: structural isomer stereoisomer
力率
The ratio of real power used by a load to the apparent power supplied, equal to the cosine of the phase angle between voltage and current.
Capacitors were installed to improve the power factor of the factory from 0.75 to 0.95.
工場の力率を0.75から0.95に改善するため、コンデンサを設置した。
Related: phasor three-phase power impedance
主成分分析
A statistical method that reduces the number of variables by transforming the data into new uncorrelated axes that capture the largest variance.
Principal component analysis reduced the 50 measured variables to three principal components.
主成分分析によって、測定した50個の変数を3つの主成分にまとめた。
優先度付きキュー
An abstract data type in which each element has a priority and the element with the highest (or lowest) priority is removed first.
Dijkstra's algorithm uses a priority queue to select the next vertex with the smallest distance.
ダイクストラ法では、距離が最小の次の頂点を選ぶために優先度付きキューを用いる。
プロトコルスタック
A layered set of communication protocols in which each layer provides services to the layer above it, such as the TCP/IP model.
In the TCP/IP protocol stack, TCP provides reliable delivery on top of IP.
TCP/IPプロトコルスタックでは、TCPがIPの上で信頼性のある配送を提供する。
Related: packet switching latency firewall
公開鍵暗号
A cryptographic system that uses a pair of keys: a public key for encryption and a private key, kept secret, for decryption.
Public-key cryptography enables secure communication without sharing a secret key in advance.
公開鍵暗号を用いると、事前に秘密鍵を共有することなく安全な通信が可能になる。
Related: digital signature cryptographic hash function two-factor authentication
パルス幅変調
A technique that controls the average power delivered to a load by switching a signal on and off rapidly and varying the fraction of time it is on.
The LED brightness is adjusted by pulse-width modulation at 1 kHz.
LEDの明るさは、1 kHzのパルス幅変調によって調整される。
Related: microcontroller inverter DC–DC converter
火砕流
A fast-moving, ground-hugging current of hot gas and volcanic fragments that flows down the slopes of a volcano.
Pyroclastic flows from Mount Unzen in 1991 caused 43 fatalities, including volcanologists and journalists.
1991年の雲仙岳の火砕流では、火山学者や報道関係者を含む43名が犠牲になった。
Related: lahar caldera magma chamber
pn接合
The boundary formed between p-type and n-type semiconductor regions, which allows current to flow easily in only one direction.
Light absorbed near the p–n junction generates electron–hole pairs in a solar cell.
太陽電池では、pn接合付近で吸収された光が電子–正孔対を生成する。
量子収率
The number of events (e.g., photons emitted) divided by the number of photons absorbed; a measure of efficiency.
The quantum yield is an important figure of merit for the optical quality of a fluorophore.
量子収率は、蛍光体の光学的品質を示す重要な性能指標である。
Related: triplet lifetime room-temperature phosphorescence photoisomerization
競合状態（レースコンディション）
A flaw in which the result of a program depends on the unpredictable timing or order of concurrent operations on shared data.
A race condition in the counter update caused some transactions to be lost.
カウンタ更新における競合状態によって、一部のトランザクションが失われた。
Related: deadlock context switch unit testing
ラセミ体
A 50:50 mixture of two enantiomers; it shows no optical rotation.
Various aspects of enzyme-catalyzed racemate resolution are discussed using examples from the hydrolysis of butanoates of glycerol derivatives.
グリセロール誘導体のブタン酸エステルの加水分解を例に、酵素触媒によるラセミ体分割のさまざまな側面を論じる。
Related: enantiomer optical purity
放射強制力
The change in the balance between incoming and outgoing energy at the top of the atmosphere caused by a factor such as greenhouse gases or aerosols.
The radiative forcing due to increased CO₂ since pre-industrial times is estimated at about 2 W m⁻².
産業革命以前からのCO₂増加による放射強制力は、約2 W m⁻²と見積もられている。
Related: glacial–interglacial cycle biogeochemical cycle El Niño–Southern Oscillation
ラジカル連鎖機構
A reaction mechanism involving radical initiation, propagation steps that regenerate a chain-carrying radical, and termination steps that remove radicals.
Sulfonylheteroarenes were amidoalkylated with alkylamides through a radical chain mechanism.
スルホニルヘテロアレーンは、ラジカル連鎖機構によってアルキルアミドでアミドアルキル化された。
Related: homolysis hydrogen atom transfer
放射年代測定
A method of determining the age of rocks or minerals by measuring the ratio of a radioactive isotope to its decay product.
Radiometric dating of the volcanic ash layer provides an age of about 7,300 years.
この火山灰層の放射年代測定によって、約7,300年という年代が得られる。
整流器
A circuit or device, usually made of diodes, that converts alternating current into direct current.
A full-wave bridge rectifier converts the AC input into a pulsating DC voltage.
全波ブリッジ整流器は、交流入力を脈流の直流電圧に変換する。
Related: p–n junction inverter DC–DC converter
酸化還元活性
The ability of a molecule or material to participate in oxidation or reduction reactions.
The redox activity of gold–molybdena catalysts supported on ceria–alumina was studied.
セリア–アルミナに担持された金–モリブデナ触媒の酸化還元活性を調べた。
Related: redox potential oxidation reduction
酸化還元電位
The electrode potential of a redox couple relative to a specified reference electrode; under comparable conditions, a more positive reduction potential indicates a greater thermodynamic tendency for reduction.
Commonly cited values for the redox potential of ergothioneine are incorrect.
エルゴチオネインの酸化還元電位として一般に引用されている値は誤りである。
Related: redox activity oxidation reduction
還元
A process in which a substance gains electrons (or loses oxygen / gains hydrogen); its oxidation number decreases.
The reduction of CO2 to CO was achieved at a low overpotential using a cobalt catalyst.
コバルト触媒を用いることで、低い過電圧でCO2からCOへの還元が達成された。
Related: oxidation redox potential electron acceptor
正則化
A technique that adds a penalty on model complexity, such as large weights, to the loss function in order to reduce overfitting.
L2 regularization improved the generalization performance of the regression model.
L2正則化によって、回帰モデルの汎化性能が向上した。
Related: overfitting loss function gradient descent
強化学習
A type of machine learning in which an agent learns to choose actions by trial and error so as to maximize cumulative reward from its environment.
Reinforcement learning was used to train a robot arm to grasp objects of different shapes.
さまざまな形状の物体をつかむようロボットアームを訓練するために、強化学習を用いた。
リレーショナルデータベース
A database that stores data in tables of rows and columns and links related tables through keys.
Student records are stored in a relational database and retrieved using SQL queries.
学生の記録はリレーショナルデータベースに保存され、SQLクエリを用いて取り出される。
Related: database normalization hash table object-oriented programming
残留応力
Stress that remains in a material after the original cause, such as welding, machining, or heat treatment, has been removed.
Shot peening introduces compressive residual stress that improves fatigue life.
ショットピーニングは圧縮残留応力を導入し、疲労寿命を向上させる。
Related: fatigue failure heat treatment additive manufacturing
共振
A condition in which a system is driven at or near its natural frequency, causing a large increase in vibration amplitude.
Resonance of the rotating shaft caused excessive vibration at 3000 rpm.
回転軸の共振によって、3000 rpmで過大な振動が生じた。
レイノルズ数
A dimensionless number that expresses the ratio of inertial forces to viscous forces in a fluid flow and predicts whether the flow is laminar or turbulent.
At Reynolds numbers above about 4000, pipe flow is usually turbulent.
レイノルズ数が約4000を超えると、管内流れは通常乱流になる。
Related: laminar flow turbulent flow viscosity
河岸段丘
A flat, step-like surface along a river valley that represents a former floodplain left above the current river level.
The river terraces along the valley record episodes of uplift and changes in sea level.
この谷沿いの河岸段丘は、隆起と海水準変動の過程を記録している。
RLC回路
A circuit consisting of a resistor, an inductor, and a capacitor, which can resonate at a frequency determined by L and C.
The RLC circuit was tuned to resonate at 455 kHz.
このRLC回路は、455 kHzで共振するように調整された。
Related: impedance time constant inductance
室温りん光
Phosphorescent emission observed at room temperature, arising from a radiative transition between states of different spin multiplicity, typically T1 → S0 in molecular systems.
Room-temperature phosphorescence (RTP) has aroused much interest due to its unique luminescence properties and wide potential applications in optoelectronics, sensing, bioimaging and security devices.
室温りん光（RTP）は、その特異な発光特性と、オプトエレクトロニクス、センシング、バイオイメージング、セキュリティデバイスへの幅広い応用の可能性から、大きな関心を集めている。
Related: triplet state intersystem crossing triplet lifetime
S波
A shear seismic body wave that moves particles perpendicular to its direction of travel and cannot pass through liquids.
The absence of S waves beyond about 104° from the source provided evidence that the outer core is liquid.
震源から約104°以遠でS波が観測されないことは、外核が液体であることの証拠となった。
Related: P wave hypocenter liquefaction
標本化定理
The theorem stating that a band-limited signal can be perfectly reconstructed from its samples if the sampling frequency is more than twice its highest frequency.
According to the sampling theorem, audio up to 20 kHz must be sampled at more than 40 kHz.
標本化定理によれば、20 kHzまでの音声は40 kHzより高い周波数でサンプリングしなければならない。
Related: analog-to-digital converter Fourier transform low-pass filter
断面二次モーメント
A geometric property of a cross-section that describes its resistance to bending, depending on how the area is distributed about an axis.
An I-beam has a large second moment of area, so it resists bending efficiently with little material.
I形鋼は断面二次モーメントが大きいため、少ない材料で効率的に曲げに抵抗する。
Related: bending moment buckling torsion
堆積相
A body of sediment or sedimentary rock with distinctive characteristics that reflect a particular depositional environment.
Detailed analysis of sedimentary facies revealed a transition from a fluvial to a shallow-marine environment.
堆積相の詳細な解析により、河川環境から浅海環境への移り変わりが明らかになった。
Related: turbidite law of superposition index fossil
地震波トモグラフィー
A technique that uses the travel times of many seismic waves to produce three-dimensional images of velocity variations inside the Earth.
Seismic tomography has imaged the subducted slab of the Pacific plate stagnating in the mantle transition zone.
地震波トモグラフィーにより、マントル遷移層に滞留する太平洋プレートの沈み込んだスラブが画像化された。
Related: P wave Moho discontinuity subduction zone
せん断力
The internal force acting parallel to a cross-section of a structural member, tending to make one part slide relative to the other.
The shear force diagram shows that the maximum shear force occurs near the supports.
せん断力図から、最大せん断力は支点付近で生じることがわかる。
Related: bending moment torsion stress concentration
SN比（信号対雑音比）
The ratio of the power of a desired signal to the power of background noise, usually expressed in decibels.
Averaging 100 measurements improved the signal-to-noise ratio by 20 dB.
100回の測定を平均することで、SN比が20 dB向上した。
一電子移動
A process in which exactly one electron moves from a donor to an acceptor, often producing radical species.
The presence of single-electron transfer (SET) steps in water oxidation processes catalyzed by first-row transition metal complexes has been recently recognized, but the computational characterization of this type of process is not trivial.
第一遷移系列金属錯体が触媒する水の酸化過程に一電子移動（SET）段階が含まれることが最近認識されてきたが、この種の過程を計算によって特徴づけることは容易ではない。
Related: electron donor electron acceptor hydrogen atom transfer
表皮効果
The tendency of alternating current to flow mainly near the surface of a conductor, increasing its effective resistance at high frequencies.
Because of the skin effect, Litz wire is used in high-frequency inductors.
表皮効果のため、高周波用インダクタにはリッツ線が用いられる。
Related: transmission line inductance impedance
斜面崩壊
The downslope movement of soil or rock when the forces driving it exceed the shear strength of the slope material.
Slope failures triggered by torrential rain are a major geohazard in the mountainous regions of western Japan.
豪雨によって引き起こされる斜面崩壊は、西日本の山間部における主要な地質災害である。
Related: liquefaction lahar chemical weathering
スマートグリッド
An electricity network that uses digital communication and control to balance supply and demand efficiently, including renewable sources.
Smart grid technologies help integrate variable solar and wind power into the network.
スマートグリッド技術は、変動する太陽光や風力の電力を電力網に統合するのに役立つ。
Related: photovoltaic cell state of charge transformer
充電率
The available capacity of a battery expressed as a percentage of its full capacity.
The battery management system estimates the state of charge from voltage and current measurements.
バッテリ管理システムは、電圧と電流の測定値から充電率を推定する。
Related: smart grid DC–DC converter microcontroller
立体異性体
Isomers that have the same atom connections but a different arrangement of atoms in 3-D space.
Practical methods for the synthesis of three stereoisomers of entecavir have been developed.
エンテカビルの三つの立体異性体を合成する実用的な方法が開発された。
Related: enantiomer structural isomer stereoselectivity
立体選択性
The preferential formation of one stereoisomer over others in a chemical reaction.
Since 1965, the stereoselectivity in azoalkane denitrogenation has attracted much attention in both synthetic organic chemistry and physical organic chemistry.
1965年以来、アゾアルカンの脱窒素反応における立体選択性は、合成有機化学と物理有機化学の両分野で大きな注目を集めてきた。
応力集中
A local increase in stress around a geometric discontinuity such as a hole, notch, or sharp corner.
The fillet radius was increased to reduce stress concentration at the corner.
角部の応力集中を低減するために、フィレット半径を大きくした。
Related: fatigue failure fracture toughness finite element method
応力–ひずみ曲線
A graph showing the relationship between the stress applied to a material and the resulting strain, used to determine its mechanical properties.
The stress–strain curve of the aluminum alloy shows no clear yield point.
このアルミニウム合金の応力–ひずみ曲線には、明確な降伏点が見られない。
構造異性体
Compounds with the same molecular formula but different connections between their atoms.
The resolution of structural isomers in mixtures of oligosaccharides is often challenging.
オリゴ糖の混合物中に含まれる構造異性体を分離することは、しばしば困難である。
Related: position isomer stereoisomer enantiomer
沈み込み帯
A convergent plate boundary where one lithospheric plate sinks beneath another into the mantle.
Large megathrust earthquakes commonly occur along subduction zones, where the oceanic plate descends beneath the continental plate.
巨大な海溝型地震は、海洋プレートが大陸プレートの下に沈み込む沈み込み帯に沿って発生することが多い。
教師あり学習
A type of machine learning in which a model is trained on input data paired with the correct output labels.
In supervised learning, the model learns to classify images using thousands of labeled examples.
教師あり学習では、モデルはラベル付きの何千もの例を用いて画像を分類することを学習する。
担持触媒
A catalyst in which active metal particles or molecules are dispersed on the surface of a solid support such as silica, alumina or carbon.
Supported catalysts can combine the high activity of molecular catalysts with the easy separation of solid catalysts.
担持触媒は、分子触媒の高い活性と固体触媒の分離の容易さを兼ね備えることができる。
超分子集合体
An organized structure formed when many molecules come together through non-covalent interactions such as hydrogen bonds or π–π stacking.
Halogen-bonded supramolecular assemblies based on phenylethynyl pyridine derivatives were prepared and characterized.
フェニルエチニルピリジン誘導体を基盤とするハロゲン結合性の超分子集合体を作製し、その特性を評価した。
Related: intermolecular interactions hydrogen bond electrostatic interaction
熱伝導率
A material property that indicates how well the material conducts heat, defined by Fourier's law.
Copper is used for heat sinks because of its high thermal conductivity.
銅は熱伝導率が高いため、ヒートシンクに用いられる。
熱効率
The ratio of the useful work output of a heat engine to the heat energy supplied to it.
The thermal efficiency of modern combined-cycle power plants exceeds 60%.
最新のコンバインドサイクル発電所の熱効率は60%を超える。
テブナンの等価回路
A simplified circuit consisting of a single voltage source in series with a single resistance that behaves identically to a complex linear circuit at two terminals.
The sensor network was replaced by its Thévenin equivalent circuit to simplify the analysis.
解析を簡単にするため、センサ回路網をそのテブナンの等価回路に置き換えた。
三相交流電力
A method of AC power generation and transmission using three sinusoidal voltages that are 120° out of phase with each other.
Large industrial motors are usually driven by three-phase power.
大型の産業用モータは、通常三相交流電力で駆動される。
Related: phasor induction motor transformer
時間計算量
A measure of how the running time of an algorithm grows as the size of its input increases.
The proposed algorithm reduces the time complexity from O(n²) to O(n log n).
提案するアルゴリズムは、時間計算量をO(n²)からO(n log n)に削減する。
Related: big-O notation NP-complete dynamic programming
時定数
The time required for the response of a first-order system, such as an RC circuit, to reach about 63% of its final value.
The RC circuit has a time constant of 1 ms, so the capacitor is almost fully charged after 5 ms.
このRC回路の時定数は1 msであるため、コンデンサは5 ms後にはほぼ完全に充電される。
Related: capacitance RLC circuit low-pass filter
ねじり
The twisting of a structural member, such as a shaft, caused by a torque applied about its longitudinal axis.
The drive shaft must withstand torsion caused by the engine torque.
ドライブシャフトは、エンジントルクによって生じるねじりに耐えなければならない。
Related: shear force second moment of area gear ratio
伝達関数
A mathematical function, usually in the Laplace domain, that relates the output of a linear time-invariant system to its input.
The transfer function of the DC motor was identified from step response data.
直流モータの伝達関数を、ステップ応答データから同定した。
Related: feedback control PID controller damping ratio
トランスフォーム断層
A strike-slip plate boundary where two plates slide horizontally past each other, often offsetting a spreading ridge.
The San Andreas Fault is a well-known continental transform fault between the Pacific and North American plates.
サンアンドレアス断層は、太平洋プレートと北米プレートの間にある大陸型トランスフォーム断層としてよく知られている。
変圧器
A static device that transfers electrical energy between circuits through electromagnetic induction, changing the voltage level of alternating current.
A step-up transformer raises the generator voltage to 500 kV for long-distance transmission.
昇圧変圧器は、長距離送電のために発電機の電圧を500 kVまで上げる。
Related: electromagnetic induction three-phase power inductance
遷移金属触媒
A catalyst containing a transition metal at its active site; catalysis may involve coordination, bond activation, and/or changes in oxidation state.
This review describes recent advances in the synthesis of novel polymerized metallocene catalysts and late transition metal catalysts for ethylene polymerization.
本総説では、エチレン重合のための新規な高分子化メタロセン触媒および後周期遷移金属触媒の合成における最近の進展を述べる。
Related: homogeneous catalyst organocatalyst cross-dehydrogenative coupling
伝送線路
A structure, such as a coaxial cable or microstrip, designed to carry high-frequency signals, whose behavior depends on its characteristic impedance.
Impedance mismatch at the end of the transmission line causes signal reflections.
伝送線路の終端でインピーダンスが整合していないと、信号の反射が生じる。
Related: impedance skin effect antenna
三重項寿命
The characteristic time over which a population of triplet excited states decays under specified conditions, accounting for all depopulation pathways.
The diffusion constant in a thin polymer film was evaluated experimentally by analyzing the triplet lifetime of single molecules.
単一分子の三重項寿命を解析することにより、薄いポリマー膜中の拡散定数を実験的に評価した。
Related: triplet state room-temperature phosphorescence quantum yield
三重項状態
An electronic state with total electron spin quantum number S = 1 and spin multiplicity 2S + 1 = 3.
Short-lived excited triplet states were studied by time-resolved EPR spectroscopy.
短寿命の励起三重項状態を時間分解EPR分光法によって調べた。
Related: intersystem crossing triplet lifetime room-temperature phosphorescence
津波の遡上高
The maximum height above sea level that a tsunami reaches as it flows inland over the land surface.
Field surveys recorded a maximum tsunami run-up of about 40 m along the Sanriku coast.
現地調査では、三陸海岸沿いで最大約40 mの津波の遡上高が記録された。
Related: subduction zone moment magnitude hypocenter
タービダイト
A sedimentary deposit laid down by a turbidity current, typically showing graded bedding from coarse sand at the base to mud at the top.
Thick turbidite sequences in the accretionary prism record repeated submarine landslides.
付加体中の厚いタービダイト層は、繰り返し発生した海底地すべりを記録している。
Related: accretionary prism sedimentary facies slope failure
乱流
An irregular fluid flow with chaotic fluctuations in velocity and pressure, and strong mixing between layers.
Turbulent flow enhances heat transfer but also increases pressure loss.
乱流は熱伝達を促進するが、圧力損失も増大させる。
Related: laminar flow Reynolds number drag coefficient
二要素認証
A security method that requires two different types of evidence, such as a password and a code sent to a phone, to verify a user's identity.
The university requires two-factor authentication for access to the student information system.
大学では、学生情報システムへのアクセスに二要素認証を必須としている。
不整合
A buried surface of erosion or non-deposition that separates younger rock layers from older ones, representing a gap in the geological record.
An angular unconformity separates the tilted Miocene strata from the overlying horizontal Pleistocene deposits.
傾斜した中新統と、その上に重なる水平な更新統の堆積物は、傾斜不整合によって隔てられている。
Related: law of superposition sedimentary facies index fossil
単体テスト（ユニットテスト）
A software testing method in which the smallest testable parts of a program, such as individual functions, are checked separately.
Unit testing helped us detect the bug before the code was merged into the main branch.
ユニットテストのおかげで、コードをメインブランチに統合する前にバグを検出できた。
Related: version control compiler object-oriented programming
バージョン管理
A system that records changes to files over time so that specific versions can be recalled and multiple people can work on the same project.
All source code for the experiment was managed with Git version control.
実験のすべてのソースコードは、Gitによるバージョン管理で管理した。
仮想マシン
A software-based emulation of a computer that runs its own operating system and applications on shared physical hardware.
Each student was given a virtual machine so that experiments would not affect the host system.
実験がホストシステムに影響を与えないよう、各学生に仮想マシンを割り当てた。
粘度（粘性係数）
A measure of a fluid's resistance to flow or to shear deformation.
The viscosity of engine oil decreases significantly as temperature rises.
エンジンオイルの粘度は、温度が上昇すると大きく低下する。
Related: Reynolds number boundary layer coefficient of friction
分圧回路
A simple circuit of two series resistors that produces an output voltage that is a fixed fraction of the input voltage.
A voltage divider was used to scale the 12 V signal down to the 3.3 V input range of the microcontroller.
12 Vの信号をマイコンの3.3 V入力範囲まで下げるために、分圧回路を用いた。
Related: Kirchhoff's voltage law Wheatstone bridge Thévenin equivalent circuit
ホイートストンブリッジ
A bridge circuit of four resistances used to measure an unknown resistance precisely or to detect small resistance changes, as in strain gauges.
The strain gauge was connected in a Wheatstone bridge to detect small changes in resistance.
抵抗のわずかな変化を検出するため、ひずみゲージをホイートストンブリッジに接続した。
Related: voltage divider operational amplifier analog-to-digital converter
降伏強さ（耐力）
The stress at which a material begins to deform plastically, so that it no longer returns to its original shape when the load is removed.
Heat treatment increased the yield strength of the steel from 350 MPa to 520 MPa.
熱処理によって、この鋼の降伏強さは350 MPaから520 MPaに向上した。
Related: stress–strain curve Young's modulus factor of safety
ヤング率（縦弾性係数）
The ratio of tensile or compressive stress to strain in the elastic region of a material, indicating its stiffness.
The Young's modulus of the carbon fiber composite was measured to be 150 GPa.
炭素繊維複合材料のヤング率は150 GPaと測定された。
ジルコンU–Pb年代測定
A radiometric dating method that uses the decay of uranium to lead in the mineral zircon, giving highly precise ages for igneous and metamorphic rocks.
LA-ICP-MS zircon U–Pb dating yielded a crystallization age of 98 ± 1 Ma for the granite.
LA-ICP-MSを用いたジルコンU–Pb年代測定により、この花崗岩の結晶化年代として98 ± 1 Maが得られた。
Related: radiometric dating half-life pluton
| Term | 日本語 | Topic |
|---|---|---|
| accretionary prism | 付加体 | Plate tectonics |
| activation energy | 活性化エネルギー | Reactions |
| actuator | アクチュエータ | Dynamics & control |
| additive manufacturing | 積層造形（付加製造） | Design & manufacturing |
| adjacency matrix | 隣接行列 | Data structures |
| alluvial fan | 扇状地 | Surface processes & geomorphology |
| analog-to-digital converter | A/D変換器（アナログ–デジタル変換器） | Digital & signals |
| antenna | アンテナ | Electromagnetics |
| aquifer | 帯水層 | Hydrology & environment |
| asthenosphere | アセノスフェア | Plate tectonics |
| asymmetric reaction | 不斉反応 | Selectivity & isomers |
| atom economy | 原子効率 | Reactions |
| attention mechanism | 注意機構（アテンション機構） | Machine learning |
| backpropagation | 誤差逆伝播法 | Machine learning |
| band gap | バンドギャップ | Semiconductors & devices |
| bandwidth | 帯域幅 | Digital & signals |
| bending moment | 曲げモーメント | Solid mechanics |
| Bernoulli’s equation | ベルヌーイの定理（ベルヌーイの式） | Fluid mechanics |
| big-O notation | ビッグオー記法（O記法） | Algorithms & complexity |
| binary search tree | 二分探索木 | Data structures |
| biogeochemical cycle | 生物地球化学的循環 | Geochronology & geochemistry |
| bipolar junction transistor | バイポーラトランジスタ | Semiconductors & devices |
| boundary layer | 境界層 | Fluid mechanics |
| brackish water | 汽水 | Hydrology & environment |
| breadth-first search | 幅優先探索 | Data structures |
| buckling | 座屈 | Solid mechanics |
| buffer overflow | バッファオーバーフロー | Networks & security |
| cache memory | キャッシュメモリ | Systems |
| caldera | カルデラ | Volcanology & petrology |
| capacitance | 静電容量（キャパシタンス） | Circuits |
| Carnot cycle | カルノーサイクル | Thermodynamics & heat transfer |
| cavitation | キャビテーション | Fluid mechanics |
| chemical weathering | 化学的風化 | Surface processes & geomorphology |
| chemoselectivity | 化学選択性 | Selectivity & isomers |
| CMOS | CMOS（相補型金属酸化膜半導体） | Semiconductors & devices |
| CNC machining | CNC加工（数値制御加工） | Design & manufacturing |
| coefficient of friction | 摩擦係数 | Design & manufacturing |
| coefficient of performance | 成績係数 | Thermodynamics & heat transfer |
| compiler | コンパイラ | Software & data |
| computational fluid dynamics | 数値流体力学 | Fluid mechanics |
| confusion matrix | 混同行列 | Machine learning |
| context switch | コンテキストスイッチ | Systems |
| convolutional neural network | 畳み込みニューラルネットワーク | Machine learning |
| covalent bond | 共有結合 | Bonding & interactions |
| creep | クリープ | Materials behavior |
| cross-dehydrogenative coupling | 脱水素型クロスカップリング | Reactions |
| cross-validation | 交差検証 | Machine learning |
| cryptographic hash function | 暗号学的ハッシュ関数 | Networks & security |
| cutting speed | 切削速度 | Design & manufacturing |
| damping ratio | 減衰比 | Dynamics & control |
| database normalization | データベースの正規化 | Software & data |
| DC–DC converter | DC–DCコンバータ | Power & energy |
| deadlock | デッドロック | Systems |
| degree of freedom | 自由度 | Dynamics & control |
| diagenesis | 続成作用 | Sedimentology & stratigraphy |
| digital elevation model | 数値標高モデル | Surface processes & geomorphology |
| digital signature | デジタル署名 | Networks & security |
| Dijkstra’s algorithm | ダイクストラ法 | Algorithms & complexity |
| dimensional tolerance | 寸法公差 | Design & manufacturing |
| dipole | 双極子 | Bonding & interactions |
| disproportionation | 不均化 | Electron transfer & redox |
| distributed system | 分散システム | Systems |
| divide and conquer | 分割統治法 | Algorithms & complexity |
| doping | ドーピング | Semiconductors & devices |
| drag coefficient | 抗力係数 | Fluid mechanics |
| dynamic programming | 動的計画法 | Algorithms & complexity |
| El Niño–Southern Oscillation | エルニーニョ・南方振動 | Atmosphere & climate |
| electrolysis | 電気分解 | Electron transfer & redox |
| electromagnetic induction | 電磁誘導 | Electromagnetics |
| electromagnetic wave | 電磁波 | Electromagnetics |
| electron acceptor | 電子受容体 | Electron transfer & redox |
| electron donor | 電子供与体 | Electron transfer & redox |
| electrophile | 求電子剤 | Reactions |
| electrostatic interaction | 静電相互作用 | Bonding & interactions |
| enantiomer | 鏡像異性体（エナンチオマー） | Selectivity & isomers |
| enthalpy | エンタルピー | Thermodynamics & heat transfer |
| entropy | エントロピー | Thermodynamics & heat transfer |
| eutrophication | 富栄養化 | Hydrology & environment |
| factor of safety | 安全率 | Design & manufacturing |
| fatigue failure | 疲労破壊 | Materials behavior |
| feature extraction | 特徴抽出 | Machine learning |
| feedback control | フィードバック制御 | Dynamics & control |
| finite element method | 有限要素法 | Solid mechanics |
| firewall | ファイアウォール | Networks & security |
| flip-flop | フリップフロップ | Digital & signals |
| focal mechanism | 発震機構（メカニズム解） | Seismology |
| Fourier transform | フーリエ変換 | Digital & signals |
| fractional crystallization | 結晶分化作用 | Volcanology & petrology |
| fracture toughness | 破壊靱性 | Materials behavior |
| frequency response | 周波数応答 | Digital & signals |
| gain | 利得（ゲイン） | Digital & signals |
| gear ratio | ギア比（歯車比） | Design & manufacturing |
| glacial–interglacial cycle | 氷期–間氷期サイクル | Atmosphere & climate |
| gradient descent | 勾配降下法 | Machine learning |
| greedy algorithm | 貪欲法（グリーディ法） | Algorithms & complexity |
| groundwater recharge | 地下水涵養 | Hydrology & environment |
| half-life | 半減期 | Geochronology & geochemistry |
| hash table | ハッシュテーブル | Data structures |
| head loss | 損失水頭 | Fluid mechanics |
| heat exchanger | 熱交換器 | Thermodynamics & heat transfer |
| heat transfer coefficient | 熱伝達率 | Thermodynamics & heat transfer |
| heat treatment | 熱処理 | Design & manufacturing |
| heterogeneous catalyst | 不均一触媒 | Catalysis |
| homogeneous catalyst | 均一触媒 | Catalysis |
| homolysis | ホモリシス（均等開裂） | Reactions |
| hydraulic conductivity | 透水係数 | Hydrology & environment |
| hydrogen atom transfer | 水素原子移動 | Electron transfer & redox |
| hydrogen bond | 水素結合 | Bonding & interactions |
| hydrolysis | 加水分解 | Reactions |
| hypocenter | 震源 | Seismology |
| impedance | インピーダンス | Circuits |
| index fossil | 示準化石 | Sedimentology & stratigraphy |
| inductance | インダクタンス | Circuits |
| induction motor | 誘導電動機（誘導モータ） | Power & energy |
| integrated circuit | 集積回路 | Semiconductors & devices |
| intermolecular interactions | 分子間相互作用 | Bonding & interactions |
| intersystem crossing | 項間交差 | Photophysics |
| inverse kinematics | 逆運動学 | Dynamics & control |
| inverter | インバータ | Power & energy |
| isostasy | アイソスタシー | Surface processes & geomorphology |
| k-means clustering | k平均法（k-meansクラスタリング） | Machine learning |
| Kirchhoff’s current law | キルヒホッフの電流則 | Circuits |
| Kirchhoff’s voltage law | キルヒホッフの電圧則 | Circuits |
| lahar | 火山泥流（ラハール） | Volcanology & petrology |
| laminar flow | 層流 | Fluid mechanics |
| large language model | 大規模言語モデル | Machine learning |
| latency | レイテンシ（遅延時間） | Networks & security |
| law of superposition | 地層累重の法則 | Sedimentology & stratigraphy |
| liquefaction | 液状化 | Seismology |
| lithosphere | リソスフェア | Plate tectonics |
| load balancing | 負荷分散 | Systems |
| logic gate | 論理ゲート | Digital & signals |
| loss function | 損失関数 | Machine learning |
| low-pass filter | ローパスフィルタ（低域通過フィルタ） | Digital & signals |
| magma chamber | マグマだまり | Volcanology & petrology |
| magnetic flux density | 磁束密度 | Electromagnetics |
| mantle convection | マントル対流 | Plate tectonics |
| Maxwell’s equations | マクスウェル方程式 | Electromagnetics |
| metamorphic facies | 変成相 | Volcanology & petrology |
| microcontroller | マイクロコントローラ（マイコン） | Measurement & embedded systems |
| mid-ocean ridge | 中央海嶺 | Plate tectonics |
| modulation | 変調 | Digital & signals |
| Moho discontinuity | モホロビチッチ不連続面（モホ面） | Plate tectonics |
| moment magnitude | モーメントマグニチュード | Seismology |
| MOSFET | MOSFET（金属酸化膜半導体電界効果トランジスタ） | Semiconductors & devices |
| multistimuli response | 多刺激応答 | Materials & phases |
| natural frequency | 固有振動数 | Dynamics & control |
| natural language processing | 自然言語処理 | Machine learning |
| nonpolar solvent | 非極性溶媒 | Solvents |
| NP-complete | NP完全 | Algorithms & complexity |
| nucleophile | 求核剤 | Reactions |
| nucleophilic substitution reaction | 求核置換反応 | Reactions |
| object-oriented programming | オブジェクト指向プログラミング | Software & data |
| operational amplifier | 演算増幅器（オペアンプ） | Circuits |
| optical purity | 光学純度 | Selectivity & isomers |
| organic solvent | 有機溶媒 | Solvents |
| organocatalyst | 有機分子触媒 | Catalysis |
| overfitting | 過学習（過剰適合） | Machine learning |
| oxidation | 酸化 | Electron transfer & redox |
| oxygen isotope ratio | 酸素同位体比 | Geochronology & geochemistry |
| P wave | P波 | Seismology |
| packet switching | パケット交換 | Networks & security |
| paleomagnetism | 古地磁気 | Atmosphere & climate |
| partial melting | 部分溶融 | Volcanology & petrology |
| permittivity | 誘電率 | Electromagnetics |
| phase transition | 相転移 | Materials & phases |
| phasor | フェーザ | Circuits |
| photoisomerization | 光異性化 | Photophysics |
| photovoltaic cell | 太陽電池セル（光起電力セル） | Power & energy |
| PID controller | PID制御器 | Dynamics & control |
| pluton | 深成岩体（プルトン） | Volcanology & petrology |
| Poisson’s ratio | ポアソン比 | Solid mechanics |
| polar solvent | 極性溶媒 | Solvents |
| position isomer | 位置異性体 | Selectivity & isomers |
| power factor | 力率 | Power & energy |
| principal component analysis | 主成分分析 | Machine learning |
| priority queue | 優先度付きキュー | Data structures |
| protocol stack | プロトコルスタック | Networks & security |
| public-key cryptography | 公開鍵暗号 | Networks & security |
| pulse-width modulation | パルス幅変調 | Measurement & embedded systems |
| pyroclastic flow | 火砕流 | Volcanology & petrology |
| p–n junction | pn接合 | Semiconductors & devices |
| quantum yield | 量子収率 | Photophysics |
| race condition | 競合状態（レースコンディション） | Systems |
| racemate | ラセミ体 | Selectivity & isomers |
| radiative forcing | 放射強制力 | Atmosphere & climate |
| radical chain mechanism | ラジカル連鎖機構 | Reactions |
| radiometric dating | 放射年代測定 | Geochronology & geochemistry |
| rectifier | 整流器 | Semiconductors & devices |
| redox activity | 酸化還元活性 | Electron transfer & redox |
| redox potential | 酸化還元電位 | Electron transfer & redox |
| reduction | 還元 | Electron transfer & redox |
| regularization | 正則化 | Machine learning |
| reinforcement learning | 強化学習 | Machine learning |
| relational database | リレーショナルデータベース | Software & data |
| residual stress | 残留応力 | Design & manufacturing |
| resonance | 共振 | Dynamics & control |
| Reynolds number | レイノルズ数 | Fluid mechanics |
| river terrace | 河岸段丘 | Surface processes & geomorphology |
| RLC circuit | RLC回路 | Circuits |
| room-temperature phosphorescence | 室温りん光 | Photophysics |
| S wave | S波 | Seismology |
| sampling theorem | 標本化定理 | Digital & signals |
| second moment of area | 断面二次モーメント | Solid mechanics |
| sedimentary facies | 堆積相 | Sedimentology & stratigraphy |
| seismic tomography | 地震波トモグラフィー | Seismology |
| shear force | せん断力 | Solid mechanics |
| signal-to-noise ratio | SN比（信号対雑音比） | Digital & signals |
| single electron transfer | 一電子移動 | Electron transfer & redox |
| skin effect | 表皮効果 | Electromagnetics |
| slope failure | 斜面崩壊 | Surface processes & geomorphology |
| smart grid | スマートグリッド | Power & energy |
| state of charge | 充電率 | Power & energy |
| stereoisomer | 立体異性体 | Selectivity & isomers |
| stereoselectivity | 立体選択性 | Selectivity & isomers |
| stress concentration | 応力集中 | Solid mechanics |
| stress–strain curve | 応力–ひずみ曲線 | Solid mechanics |
| structural isomer | 構造異性体 | Selectivity & isomers |
| subduction zone | 沈み込み帯 | Plate tectonics |
| supervised learning | 教師あり学習 | Machine learning |
| supported catalyst | 担持触媒 | Catalysis |
| supramolecular assembly | 超分子集合体 | Bonding & interactions |
| thermal conductivity | 熱伝導率 | Thermodynamics & heat transfer |
| thermal efficiency | 熱効率 | Thermodynamics & heat transfer |
| Thévenin equivalent circuit | テブナンの等価回路 | Circuits |
| three-phase power | 三相交流電力 | Power & energy |
| time complexity | 時間計算量 | Algorithms & complexity |
| time constant | 時定数 | Circuits |
| torsion | ねじり | Solid mechanics |
| transfer function | 伝達関数 | Dynamics & control |
| transform fault | トランスフォーム断層 | Plate tectonics |
| transformer | 変圧器 | Power & energy |
| transition metal catalyst | 遷移金属触媒 | Catalysis |
| transmission line | 伝送線路 | Electromagnetics |
| triplet lifetime | 三重項寿命 | Photophysics |
| triplet state | 三重項状態 | Photophysics |
| tsunami run-up | 津波の遡上高 | Seismology |
| turbidite | タービダイト | Sedimentology & stratigraphy |
| turbulent flow | 乱流 | Fluid mechanics |
| two-factor authentication | 二要素認証 | Networks & security |
| unconformity | 不整合 | Sedimentology & stratigraphy |
| unit testing | 単体テスト（ユニットテスト） | Software & data |
| version control | バージョン管理 | Software & data |
| virtual machine | 仮想マシン | Systems |
| viscosity | 粘度（粘性係数） | Fluid mechanics |
| voltage divider | 分圧回路 | Circuits |
| Wheatstone bridge | ホイートストンブリッジ | Measurement & embedded systems |
| yield strength | 降伏強さ（耐力） | Solid mechanics |
| Young’s modulus | ヤング率（縦弾性係数） | Solid mechanics |
| zircon U–Pb dating | ジルコンU–Pb年代測定 | Geochronology & geochemistry |
該当する用語がありません。綴りを変えるか、日本語で検索してみてください。
No matching terms.
