按方法、领域与证据探索科学。

Second-Order Reliability Method

The Second-Order Reliability Method (SORM) is an extension of FORM that improves failure probability estimates by accounting for the curvature of the limit-state surface at the design point. Introduced by Fiessler, Neumann, and Rackwitz in 1979, SORM provides more accurate approximations for nonlinear failure surfaces

materials science

Selected Area Electron Diffraction

Selected Area Electron Diffraction (SAED) is a crystallographic technique in transmission electron microscopy that obtains electron diffraction patterns from micron-sized or sub-micron crystalline regions. Developed from fundamental principles of electron wave behavior and integrated into TEM instruments by the mid-20t

text mining

Semantic Parsing

Semantic parsing is a natural-language-processing task that converts free-text utterances into executable formal representations such as SQL queries, logical forms, or Abstract Meaning Representations (AMR). Established in its supervised learning form by Zelle and Mooney in 1996 and scaled to cross-domain settings by t

text mining

Semantic Role Labeling

Semantic role labeling, introduced by Gildea and Jurafsky in 2002, is a natural-language-processing task that assigns semantic roles — who did what to whom, where, when, and how — to the components around a verb (predicate) in a sentence. It turns plain text into structured predicate-argument representations and is a f

text mining

Semantic Similarity

Semantic similarity analysis measures how close in meaning two texts are, rather than how many words they share on the surface. Building on the Sentence-BERT work of Reimers and Gurevych (2019), it represents each text as a vector and compares those vectors so that paraphrases score high even when their wording differs

text mining

Sentiment Analysis

Sentiment analysis, also called opinion mining, is a natural-language-processing task that detects the emotional tone of text — typically classifying it as positive, negative, or neutral. It turns unstructured opinion text into structured, quantifiable polarity signals using one of three families of approaches: sentime

aerospace

SGP4 TLE Propagation

SGP4 (Simplified General Perturbations 4) is a rapid orbital propagation method that predicts satellite position and velocity from Two-Line Element (TLE) sets published by NORAD. Developed in the 1970s, SGP4 accounts for atmospheric drag, gravitational perturbations, and solar radiation pressure using simplified analyt

telecommunications

Shannon Capacity

Shannon's channel capacity theorem, published in 1948, establishes the maximum rate at which information can be reliably transmitted over a noisy channel. Expressed as C = B log2(1 + S/N) for additive white Gaussian noise (AWGN), it is a fundamental bound in information theory and communications engineering. Shannon pr

mining engineering

Shrinking Core Model

The Shrinking Core Model, formalized by Szekely, Evans, and Sohn in 1976, describes the kinetics of chemical reactions between solid ore particles and surrounding fluids (leaching solutions, roasting gases). As the reaction proceeds from the particle surface inward, an unreacted core shrinks while products accumulate i

control theory

Simultaneous Localization and Mapping

Simultaneous Localization and Mapping (SLAM) is the problem of enabling a mobile robot to build a map of its environment while simultaneously determining its own location within that map using noisy sensor measurements. Formulated by Durrant-Whyte and Bailey in 2006, SLAM is fundamental to autonomous robotics, enabling

mining engineering

Slag Basicity

Slag basicity is a measure of the composition of slag formed during smelting and roasting operations. It is typically expressed as the ratio of basic oxides (CaO, MgO) to acidic oxides (SiO2). Basicity controls slag fluidity, viscosity, and reactivity, directly affecting metal recovery, processing temperature, and prod

control theory

Sliding Mode Control

Sliding Mode Control (SMC) is a robust nonlinear control technique that forces a system to follow a predetermined surface (the sliding surface) in state space by using discontinuous (bang-bang or high-frequency switching) control inputs. Developed by Utkin and further advanced by Slotine, SMC is remarkably insensitive

civil engineering

Slope Stability (Bishop-Janbu)

The Bishop and Janbu methods are limit equilibrium approaches for analyzing slope stability, computing the factor of safety against shear failure along a potential slip surface. Developed by Bishop (1955) and Janbu (1954), these methods remain the most widely used tools in geotechnical engineering for evaluating cut sl

text mining

Slot Filling

Slot filling is a natural-language-understanding task that extracts predefined template fields — such as date, location, or product name — from a user utterance. It emerged as a core component of dialogue systems and form-based information extraction, and became widely studied after Goo et al. (2018) introduced the Slo

telecommunications

Slotted ALOHA

Slotted ALOHA is a fundamental random access protocol enabling multiple devices to share a wireless channel without centralized coordination. Introduced by Abramson (1970) and refined by Roberts (1975), it divides time into fixed slots and allows devices to transmit at the beginning of a slot with a fixed probability.

electrical engineering

Smart Grid State Estimation

Power system state estimation infers the real-time voltage and phase angle at every bus in a power network from redundant measurements of power flows and voltages. It is the foundation of modern grid operations, enabling real-time monitoring, contingency analysis, and optimal control. Advanced state estimation with syn

electrical engineering

Smith Chart

The Smith Chart is a graphical tool for visualizing and manipulating complex impedances and reflection coefficients on transmission lines. Introduced by Phillip Smith in 1939, the chart maps the complex reflection coefficient plane to a circular chart, enabling intuitive graphical analysis of transmission line problems

text mining

Social Media NLP

Social Media NLP is a specialised natural-language-processing pipeline designed for the short, noisy, and informal text that appears on platforms such as Twitter, Reddit, and comment sections. Unlike general-purpose NLP, this pipeline accounts for platform-specific conventions — hashtags, emojis, abbreviations, and cod

software engineering

Software Complexity Metrics

Software complexity metrics quantify the structural and operational difficulty of code through numerical measurements. Introduced by Thomas McCabe in 1976, cyclomatic complexity became the foundational approach. These metrics assess maintainability, testability, and defect risk, enabling teams to identify problematic c

software engineering

Software Reliability Model

Software reliability models predict the behavior of failure rates during testing and operation, estimating when software achieves required reliability targets. Introduced by Goel and Okumoto (1979), these stochastic models capture how defect discovery declines as testing progresses. Organizations use reliability models

telecommunications

Software-Defined Networking

Software-Defined Networking (SDN) is a network architecture paradigm that decouples the control plane (routing decisions) from the data plane (packet forwarding). Introduced by McKeown et al. (2008) with OpenFlow, SDN enables network programmability by centralizing control logic in software-based controllers that direc

environmental engineering

Soil Remediation

Soil remediation encompasses a suite of technologies and strategies to treat contaminated soil at sites with elevated levels of organic compounds, heavy metals, radionuclides, or other hazardous substances. Systematized by the US EPA in the 1980s following industrial accidents and legacy contamination discoveries, soil

civil engineering

Soil-Structure Interaction

Soil-structure interaction (SSI) analysis accounts for the dynamic coupling between a structure and its supporting foundation soil, recognizing that the soil is not infinitely rigid. Formalized by Veletsos in 1974, this approach reveals how foundation compliance, radiation damping, and kinematic effects modify the stru

architecture

Space Syntax Analysis

Space Syntax Analysis is a quantitative method for assessing spatial configuration in buildings and urban environments through graph-based representations. Developed by Bill Hillier and Julienne Hanson in the 1980s, it quantifies how spatial layout affects human movement, visibility, and social interaction.

aerospace

Specific Excess Power

Specific excess power (Ps) is a metric that quantifies the rate of change of energy per unit weight, representing how quickly an aircraft can trade speed for altitude (or vice versa) at a given flight condition. Developed by John Boyd in the 1970s as part of energy maneuverability theory, Ps is essential for assessing

text mining

Speculation Detection

Speculation detection, also known as hedging analysis, is a natural-language-processing task that identifies epistemic uncertainty markers — words and phrases such as 'may', 'possibly', 'it is suggested that' — within scientific, biomedical, and news texts. Formalised by Hyland (1996) for scientific writing and benchma

text mining

Spelling and Grammar Check

Spelling and grammar checking is a text-mining task that detects spelling mistakes and grammatical errors in text and proposes corrections. Building on Naber's rule-based style and grammar checker (2003) and Norvig's statistical spelling corrector (2009), it is used for data-quality assessment and text normalisation be

text mining

Stance Detection

Stance detection is a natural-language-processing task that decides the position a text takes toward a specific claim, event, or topic — labelling it as favor, against, or neutral. Formalised by Mohammad et al. in the SemEval-2016 Task 6 shared task, it differs from plain sentiment analysis because the label is always

software engineering

Static Code Analysis

Static code analysis automatically examines source code without execution, detecting potential bugs, security vulnerabilities, code smells, and style violations. Pioneered by Engler and Pugh (2001), automated analysis tools scan codebases at scale, identifying defect patterns faster than manual review. Organizations in

electrical engineering

Static Timing Analysis

Static Timing Analysis (STA) is a non-simulation method for verifying that digital circuits meet timing constraints (clock frequencies, setup/hold times, propagation delays). Introduced systematically by Bhatnagar et al. in the 1990s, STA computes worst-case and best-case path delays by analyzing logic paths without si

mining engineering

Stereographic Slope Analysis

Stereographic projection is a graphical method for analyzing slope stability by representing the three-dimensional orientation of discontinuities (joints, bedding, faults) and the pit slope on a two-dimensional stereographic net (stereonet). The method enables rapid visual identification of potentially unstable slope g

mining engineering

Stope Layout

Stope layout optimization is the process of designing the size, shape, and spatial arrangement of underground mine excavations (stopes) to maximize ore recovery while maintaining safety and economic viability. It balances the desire for large extraction volumes against rock mechanics constraints and support costs. The

environmental engineering

Stormwater Management

Stormwater management is the planning and engineering of urban water systems to control, treat, and utilize rainwater runoff from developed areas. Traditional approaches (pipes, detention basins) conveyed runoff rapidly to streams or treatment plants; modern green infrastructure approaches (permeable pavements, bioswal

architecture

Structural Form-Finding

Structural Form-Finding is a computational method for discovering structural geometries that are efficient under given loads and constraints. Pioneered by Heinz Schek in 1974, it reverses traditional structural design: rather than imposing a predetermined form and then analyzing whether it is strong enough, form-findin

civil engineering

Structural Health Monitoring

Structural Health Monitoring (SHM) is a process-based engineering methodology used in civil, mechanical, and aerospace engineering to continuously assess the condition of structures — bridges, buildings, dams, pipelines, and aircraft — through embedded or attached sensor networks. By acquiring real-time or periodic mea

text mining

Structured Text Extraction

Structured text extraction is a document-processing pipeline that automatically identifies and pulls tables, form fields, and structured data from PDF, HTML, and scanned documents. It converts heterogeneous document layouts into machine-readable, analysis-ready records and is widely used in data collection workflows, d

text mining

Subjectivity Detection

Subjectivity detection is a natural-language-processing task that classifies whether a sentence or document conveys objective (neutral information) or subjective (personal opinion, emotion) content. Grounded in the opinion-annotation work of Wiebe and colleagues (2005) and Pang and Lee (2004), it is most often used as

electrical engineering

Subsynchronous Resonance

Subsynchronous Resonance (SSR) is a phenomenon where frequencies below the synchronous frequency (50/60 Hz) are amplified in power systems, causing oscillations that can damage turbines. First observed in Bushland, Texas in 1977, SSR results from interaction between series-compensated transmission lines and synchronous

biomaterials

Swelling and Degradation

The swelling and degradation assay measures how biomaterial scaffolds absorb water (swelling) and lose mass over time due to degradation. Developed by Wichterle and Lim in 1960 for hydrogels, the assay is fundamental for characterizing hydrogels, synthetic polymers, and composite scaffolds intended for tissue engineeri

electrical engineering

Symmetrical Components

Symmetrical Components is a mathematical technique for analyzing unbalanced three-phase electrical circuits by decomposing them into balanced component sets. Introduced by Charles Fortescue in 1918, the method transforms the complex analysis of unbalanced systems into simpler balanced equivalent circuits. Symmetrical c

manufacturing

Taylor Tool Life

Taylor's tool life equation is an empirical relationship predicting how long a cutting tool remains usable before dulling or breaking, expressed as a function of cutting speed, feed rate, and depth of cut. Formulated by Frederick Winslow Taylor in 1907 from systematic experiments on metal cutting, this method provides

aerospace

TCAS

TCAS (Traffic Collision Avoidance System) is an airborne safety system that detects nearby aircraft using radar and mode C altitude reports, then provides traffic advisories (TAs) and recommended collision avoidance maneuvers (RAs) to flight crews. Mandated globally on commercial aircraft since 2000, TCAS is considered

software engineering

Technical Debt Measurement

Technical debt represents accumulated shortcuts, deferred maintenance, and design compromises that incur future costs through slower development, higher defect rates, and deployment difficulty. Introduced by Ward Cunningham (1992), technical debt measurement quantifies these burdens using metrics like code complexity,

text mining

Temporal Expression Extraction

Temporal expression extraction is a natural-language-processing task that detects dates, times, durations, and frequencies in text and normalises them to the TimeML/TIMEX3 standard. Building on the TempEval shared task introduced by Verhagen et al. (2007), it turns time references scattered through free text into struc

aerospace

TERCOM

Terrain Contour Matching (TERCOM) is a terrain-aided navigation method that corrects position estimates by matching altimeter measurements against a stored digital elevation map (DEM). Developed by Boeing in the 1980s for cruise missile guidance, TERCOM enables accurate navigation in GPS-denied environments by exploiti

civil engineering

Terzaghi Consolidation

Terzaghi consolidation theory describes how water-saturated clay soils compress over time as excess pore water pressure dissipates and effective stress increases. Formulated by Karl Terzaghi in 1943, this foundational theory enables prediction of settlement rates for foundations on compressible soils, a critical design

text mining

Text Classification

Text classification, also called text categorization, is a supervised natural-language-processing task that automatically assigns documents to predefined categories. Building on the support-vector-machine approach to text categorization established by Joachims (1998) and consolidated in the text-mining literature by Ag

text mining

Text Coherence Scoring

Text coherence scoring computes a document-level coherence score with machine learning, rooted in the entity-based local coherence model introduced by Barzilay and Lapata (2008). It measures how well the sentences of a text hang together, using either an entity-grid model, a graph-based approach, or a transformer-based

text mining

Text Complexity Analysis

Text complexity analysis measures the linguistic difficulty of a text along dimensions such as syntactic complexity (sentence length, embedded clauses), lexical density, and referential chains. Grounded in readability research consolidated by Vajjala and Meurers (2014) and Crossley and colleagues (2011), it turns prose

text mining

Text Deduplication

Text deduplication is a corpus-quality pipeline that identifies and removes exact and near-duplicate documents from large text collections. Grounded in Andrei Broder's 1997 resemblance theory, it is widely used to improve dataset quality for machine learning model training, search engine indexing, and any downstream NL

text mining

Text Frequency Analysis

Text frequency analysis is a descriptive text-mining method that counts how often words, n-grams, and phrases occur in a corpus to reveal content patterns and dominant themes. It rests on the frequency-distribution insight formalised by George K. Zipf (1949), that a few terms occur very often while most are rare, and i

text mining

Text Infilling

Text infilling is a natural-language-processing task that completes missing words, phrases, or spans in a document by exploiting the surrounding context. Introduced as the cloze procedure by Wilson L. Taylor in 1953 as a readability measure, it was reformulated for neural models by Zhu et al. (2019) and is now used for

text mining

Text Network Analysis

Text network analysis models the words or concepts in a text as nodes and their co-occurrences as edges, then uses network metrics to reveal the structure of meaning. The approach was advanced by Diesner and Carley (2005) for communication networks and by Paranyushkin (2011) for tracing the pathways of meaning circulat

text mining

Text Normalization

Text normalization is an NLP preprocessing pipeline that converts noisy, abbreviated, or misspelled text — such as SMS messages, social-media posts, and OCR output — into a clean, standardised form. It is a prerequisite step for virtually every downstream NLP task, ensuring that inconsistent surface forms do not degrad

text mining

Text Regression

Text-based regression predicts a continuous target variable using features extracted from text — TF-IDF scores, embeddings, or n-grams — as the independent variables. Building on the text-as-data programme consolidated by Gentzkow, Kelly and Taddy (2019), it lets a numeric outcome such as a price, a rating, or a sentim

text mining

Text Segmentation

Text segmentation divides a long document into meaningful sections (segments) along topic or discourse boundaries. Introduced for subtopic passages by Marti A. Hearst's TextTiling (1997), it supports document-structure analysis and the detection of topic transitions in continuous text.

text mining

Text Summarization

Automatic text summarization is a natural-language-processing task that condenses long documents into shorter summaries while preserving their key information. It works through one of two families of approaches — extractive summarization, which selects the most important spans from the source, or abstractive summarizat

text mining

Textual Entailment

Textual entailment, also known as natural language inference (NLI), is the natural-language-processing task of deciding whether one piece of text (the premise) entails a second piece of text (the hypothesis), contradicts it, or is neutral with respect to it. Formalised by the PASCAL Recognising Textual Entailment Chall

text mining

TF-IDF

TF-IDF, introduced by Salton and Buckley (1988), is a term-weighting scheme that scores each word in a document by how often it appears there and how rare it is across the whole collection. It turns raw text into weighted document vectors, giving high weight to terms that are frequent in one document but uncommon elsew

aerospace

Theodorsen Flutter

Theodorsen flutter analysis is a classical aeroelastic method for predicting the onset of flutter, a self-excited oscillation where aerodynamic forces interact with elastic structural motion to cause rapid growth of oscillations. Developed by Theodore Theodorsen in 1935, the method uses frequency-domain analysis with T