Formal Semantics

This paper provides a new account of positive versus negative antonyms. The data includes well-known linguistic generalizations regarding negative adjectives, such as their incompatibility with measure phrases (cf. two meters tall/ *short) and ratio phrases (twice as tall/ #short) as well as the impossibility of truly crosspolar comparisons (*Dan is taller than Sam is short). These generalizations admit a variety of exceptions, e.g., positive adjectives that do not license measure phrases (cf. #two degrees warm/cold) and rarely also negative adjectives that do (cf. two hours late/early). Furthermore, new corpus data is presented regarding the use of twice with positive and negative adjectives. The analysis the paper presents supposes that grammar associates gradable adjectives with measure functions-mapping of entities to a set of degrees isomorphic to the real numbers (Kennedy, Projecting the

The mass-count distinction is a morpho-syntactic distinction among nouns that is generally taken to reflect a semantic distinction. There are three approaches to what such a semantic distinction may consist in: an extension-based approach, an object-based approach, and a more recent grammar-based approach. The paper will pursue the grammar-based approach, on which count categories convey a notion of unity at a level of 'grammaticized individuation' to use Rothstein's (2017) term. It will argue that verbs with respect to their Davidsonian event argument position exhibit the diagnostics of mass, rather than count. This is correctly predicted by the grammar-based approach, but not object- or extension-based approaches. The paper will account for the mass diagnostics of verbs in terms of semantic selection.

This report gives an overview of the work performed by the Programming Research Group as part of the European collaborative ESPRIT II REDO project (no. 2487). This work covered the areas of reverse-engineering: redocumentation and re-engineering; validation: post-hoc verification and generation of correct code from specifications; maintenance: new languages and methods to support maintenance. Research in areas of concurrent programming and decompilation were also performed.

The specification of all aspects of a programming language requires adequate formal models and tool support. Montages specifications combine graphical and textual elements to yield language descriptions similar in structure, length, and complexity to those in common language manuals, but with a formal semantics. A broad range of people involved in programming language design and use may find it convenient to use Montages in combination with the tool GEM-MEX. It allows the automatic generation of high-quality documents, type-checkers, interpreters and symbolic debuggers.

In large programs such as NASA Exploration, multiple systems that interact via safety-critical protocols are already designed with different Statechart variants. To verify these safety-critical systems, a unified framework is needed based on a formal semantics that captures the variants of Statecharts. We describe Polyglot, a unified framework for the analysis of models described using multiple Statechart formalisms. In this framework, Statechart models are translated into Java and analyzed using pluggable semantics for different variants operating in a polymorphic execution environment. The framework has been built on the basis of a parametric formal semantics that captures the common core of Statecharts with extensions for different variants, and addresses previous limitations. Polyglot has been integrated with the Java Pathfinder verification tool-set, providing analysis and test-case generation capabilities. We describe the application of this unified framework to the analysis of NASA/JPL's MER Arbiter whose interacting components were modeled using multiple Statechart formalisms.

Current and future (conventional) notations used in Conceptual Modeling Techniques should have a precise (formal) semantics to provide a well-defined software development process, in order to go from specification to implementation in an automated way. To achieve this objective, the OO-Method approach to Information Systems Modeling presented in this paper attempts to overcome the conventional (informal)/formal dichotomy by selecting the best ideas from both approaches. The OO-Method makes a clear distinction between the problem space (centered on what the system is) and the solution space (centered on how it is implemented as a software product). It provides a precise, conventional graphical notation to obtain a system description at the problem space level, however this notation is strictly based on a formal OO specification language that determines the conceptual modeling constructs needed to obtain the system specification. An abstract execution model determines how to obtain the software representations corresponding to these conceptual modeling constructs. In this way, the final software product can be obtained in an automated way. r

We first advocate that the AUML (Agent Unified Modeling Language) notation, even in its new version, is not precise enough to adequately describe protocols. This problem was long identified by Harel and we propose to follow his solution: extend sequence diagrams with a ...

This paper presents ArchiTRIO (Architectural TRIO), a new temporal logic language which combines a subset of the UML notation with a precise formal semantics inspired from the authors’ experiences. ArchiTRIO allows developers to use standard UML 2.0 notation to describe non-critical aspects of systems, but it also offers a complementary formal notation, fully integrated with the UML one, to represent those system aspects that require precise modeling.

[This paper was written as a squib for an introductory class on semantics. It presents original research, but does so without the benefit of an overview of the literature.]

The use of the word ‘the’ in English with singular nouns often denotes a referent; under generalized quantifier theory, this usage is reinterpreted as a quantifier, allowing the noun phrase to be conjoined with other quantified expressions. However, a look at other classes of nouns—bare plurals, mass nouns and generic nouns—demonstrates that the article is more closely tied to Carlsonian level than it is to semantic type; the definite article marks reference at the object level. This usage contrasts with articular systems in other languages, such as French.

Safety critical software requires integrating verification techniques in software development methods. Software architectures must guarantee that developed systems will meet safety requirements and safety analyses are frequently used in the assessment. Safety engineers and software architects must reach a common understanding on an optimal architecture from both perspectives. Currently both groups of engineers apply different modelling techniques and languages: safety analysis models and software modelling languages. The solutions proposed seek to integrate both domains coupling the languages of each domain. It constitutes a sound example of the use of language engineering to improve efficiency in a software-related domain. A model-driven development approach and the use of a platform-independent language are used to bridge the gap between safety analyses (failure mode effects and criticality analysis and fault tree analysis) and software development languages (e.g. unified modelling language). Language abstract syntaxes (metamodels), profiles, language mappings (model transformations) and language refinements, support the direct application of safety analysis to software architectures for the verification of safety requirements. Model consistency and the possibility of automation are found among the benefits.

An approach for modelling configurable software product families (CSPFs) and for automated configuring of product individuals using the models is presented. It is based on a similar approach for configuring physical products. The conceptual foundation and syntax of the Koalish modelling language used for this purpose are defined. The language extends Koala, a component model and architecture description language, with explicit variation modelling mechanisms. Koalish is further provided a formal semantics by defining a translation from it to Weight Constraint Rule Language (WCRL), a form of logic programs. This allows using an existing inference tool for WCRL, smodels, to implement the reasoning needed in the configurator. The configurator is able to construct all valid product individuals, with respect to a Koalish model of a CSPF, that satisfy a given set of requirements. The implemented functionality of the configurator has been tested using small-scale toy examples, for which it performs adequately.

In this paper I address a typological puzzle concerning complementary distribution of classifiers and plural markers. I discuss a possible interpretation of a particular type of the Polish word 'para' ('pair of') as a classifier. The analysis uses formal semantic plurality framework of Landman (2000).

In “A Defense of Presentism,” Ned Markosian addresses the problem of singular propositions about non-present objects. The proposed solution uses a paraphrasing strategy that differentiates between two kinds of meaning in declarative sentences, and also distinguishes between two truth-conditions for singular propositions. The solution, however, is unsatisfactory. I demonstrate that both truth-conditions suffer from the same problems in spite of the examples used to support the claim that one is a proper treatment for singular propositions. Part of the difficulty is in the limited expressivity of logical formalisms, a of time, but one which calls for greater attention.

The Formal Semantics of Programming Languages provides the basic mathematical techniques necessary for those who are beginning a study of the semantics and logics of programming languages. These techniques will allow students to invent, formalize, and justify rules with which to reason about a variety of programming languages. Although the treatment is elementary, several of the topics covered are drawn from recent research, including the vital area of concurency. The book contains many exercises ranging from simple to miniprojects.Starting with basic set theory, structural operational semantics is introduced as a way to define the meaning of programming languages along with associated proof techniques. Denotational and axiomatic semantics are illustrated on a simple language of while-programs, and fall proofs are given of the equivalence of the operational and denotational semantics and soundness and relative completeness of the axiomatic semantics. A proof of Godel's incompleteness theorem, which emphasizes the impossibility of achieving a fully complete axiomatic semantics, is included. It is supported by an appendix providing an introduction to the theory of computability based on whileprograms.Following a presentation of domain theory, the semantics and methods of proof for several functional languages are treated. The simplest language is that of recursion equations with both call-by-value and call-by-name evaluation. This work is extended to lan guages with higher and recursive types, including a treatment of the eager and lazy lambda-calculi. Throughout, the relationship between denotational and operational semantics is stressed, and the proofs of the correspondence between the operation and denotational semantics are provided. The treatment of recursive types-one of the more advanced parts of the book-relies on the use of information systems to represent domains. The book concludes with a chapter on parallel programming languages, accompanied by a discussion of methods for specifying and verifying nondeterministic and parallel programs. DOWNLOAD http://fb.me/2X2m3MYWi http://bit.ly/1qi7wSp A complete proof system for SCCS with modal assertions , Glynn Winskel, 1985, Parallel processing (Electronic computers), 23 pages.. Denotational Semantics The Scott-Strachey Approach to Programming Language Theory, Joseph Stoy, 1977, Computers, 414 pages. "First book-length exposition of the denotational (or mathematical' or`functional') approach to the formal semantics of programming languages (in contrast to `operational. Transitions and Trees An Introduction to Structural Operational Semantics, Hans H Ttel, Apr 29, 2010, Computers, 272 pages. A rigorous, self-contained introduction to the theory of operational semantics of programming languages and its use..

Does it make sense to employ modern logical tools for ancient philosophy? This well-known debate2 has been re-launched by the indologist Piotr Balcerowicz, questioning those who want to look at the Eastern school of Jainism with Western glasses. While plainly acknowledging the legitimacy of Balcerowicz’s mistrust, the present paper wants to propose a formal reconstruction of one of the well-known parts of the Jaina philosophy, namely: the saptabhaṅgī, i.e. the theory of sevenfold predication. Before arguing for this formalist approach to philosophy, let us return to the reasons to be reluctant at it. For one thing, Balcerowicz (2008) made a clear-cut distinction between a constructivist and a reductionist method of interpretation. The former is defined by Balcerowicz (2008: 4), where the so-called “constructivist” method is not to be confused with the philosophy of mathematics and merely amounts to the exercise of formal reconstruction:

The International Standard on Petri nets, ISO/IEC 15909, provides a formal semantics and syntax to enable model interchange and industrial dissemination. Part 2 defines a concrete interchange format as an XML-based language: PNML. This language is bound to evolve together with future developments of the standard.

Este manual pretende dar uma visão diferente de língua e ensino nas aulas de português. Na primeira unidade, mostramos que essa perspectiva não aparece nos Parâmetros Curriculares Nacionais para o ensino de português. Trata-se, portanto, de uma rota alternativa, mas que tem suporte em pesquisas já realizadas com falantes de diversas línguas, que indicam que há uma relação positiva entre o aluno construir hipóteses sobre a sua língua e ter um desempenho melhor na língua escrita, além de ter um efeito positivo no ensino de ciências e de matemática. A segunda unidade é composta por uma série de informações que permitem sabermos (note: não é acharmos, nem pensarmos, mas sabermos) que há uma faculdade da linguagem. A terceira unidade introduz o método científico para a análise das línguas. Ensinar ciência através da construção de gramáticas pode ser não apenas muito divertido, mas principalmente uma maneira de re-significar a língua falada, em especial na nossa cultura bacharelesca que vê a língua das gentes com tanto preconceito, afinal mostrar a sua gramática é desfazer preconceitos que usurpam o nosso direito à nossa língua. O português brasileiro é o tópico da quarta e última unidade. Professores de português no Brasil precisam saber como é essa língua, que língua é essa que nós falamos.
ISBN: 978-85-61482-61-9

1972. Weak and Strong Completeness in Sentential Logic, Logique et Analyse 59/60, 429–34.  MR0337476 (49 #2245)

This is another study illustrating the fruitfulness of thinking of “logics” as three-part systems composed of a language, a semantics [or model theory] and a deductive system [or proof theory]. For simplicity we take a fixed language for sentential logic [or propositional logics] with a fixed standard two-valued semantics, but we “vary” deductive systems. In the 1960s when this paper was written, it was still widely assumed that a “logic” was “determined” by its theorems, by what it could “prove”. The vague assumption was that once the theorems were fixed, it was somehow automatic which conclusions were derivable from given premises.
The purpose of this paper is to give a method which weakens deriving power of a sentential logic while leaving proving power unchanged. In particular if the method is applied to a strongly complete logic the resultant will not have strong completeness but it will retain weak completeness. Moreover, because of the nature of the method two added facts obtain.
First, weak completeness of the resultant is always an obvious corollary to weak completeness of the operand, so that no new completeness proof need be constructed. Second, failure of strong completeness in the resultant is always obvious, so no multi-valued matrices need be constructed. The method applies to all sentential logics formulated using only axiom schemes and schematically statable rules. These results reaffirm, generalize, and simplify a result of Hiz [Journal of Symbolic Logic, 24 (1959), pp. 193-202].

and able to practice TBI, a real paradigm change for many+ What would still be worth investigating, however, are other age groups, such as young learners, and how effective TBI is at the very beginning of foreign language learning with a population of young learners+ That said, this volume is valuable for enhancing our understanding of tasks and how they differ from more traditional communicative language teaching activities+ Although the authors state that this book is geared toward adult professional learners, the designs shown and the ideas put forth could easily be transferred to both young learners and adolescents+

Esta coletânea apresenta alguns artefatos expostos ao público
na Feira de Linguística, no dia 23 de fevereiro de 2019, atividade
com a qual encerramos a extensão “O saber científico no
espaço escolar: construção de gramática e olimpíada de Linguística”,
supervisionada pelas professoras Roberta Pires de Oliveira
e Sandra Quarezemin. O objetivo da extensão era desenvolver novas maneiras de ensinar língua e gramática na escola do Brasil do século XXI, avançando a linha mestre em Pires de Oliveira & Quarezemin (2016) de que construção de gramáticas é uma heurística eficaz para não apenas os alunos entenderem como funciona uma língua e como se constrói uma teoria científica, mas, principalmente, como uma maneira de conscientização sobre fenômenos gramaticais. Isso tem efeito positivo na leitura, na compreensão do mundo natural e na cidadania. Os professores, que participaram do curso, tiveram como tarefa construir um artefato em gramática. Artefatos, na arqueologia, são objetos produzidos pelo homem. O desafio é construir objetos gramaticais que permitam entender as línguas naturais, incluindo programas que repliquem o comportamento linguístico. Robôs que entendem a nossa fala, que conversam. Esses artefatos foram apresentados na Feira Linguística.
ISBN 978-65-87206-02-8

Ontologies are instruments for capturing and using formal semantics, and are often the result of a ”central committee controlled” style of working. A new trend on the Web is the increasing popularity of folksologies in the form of social bookmarking sites. Folksologies provide informal semantics and can be created and adopted by anybody anytime anywhere on the Internet. Shared meaning in a folksology emerges through the use of tags that are used to bookmark web pages, their usage frequency being considered a reliable indicator of their usefulness and acceptance. Rather than choosing for either ontologies or folksologies, hybrid emergent semantics systems are needed that combine elements of both perspectives, depending on the particular application. There is a need to analyse the larger picture (including the full range of semantics’ functionalities in their context of use. In this paper, we outline a number of key design characteristics of emergent semantics systems (ESS). We examine the functionalities of two existing examples of well-known ESSs: del.icio.us and Piggy Bank. Using the results of this comparison, we introduce DogmaBank as a proof of concept implementation of a next-generation ESS that introduces a more advanced combination of lexical and conceptual emergent semantics functionalities.

One of the most important courses in the linguistics curriculum is an introduction
to semantics for advanced undergraduate and/or beginning graduate students.
The highly technical nature of this material, the intricacy of the theoretical issues
involved, and the relevance for the students’ further studies and future academic
careers make it extremely desirable to have a good textbook for this course.
There are a number of options for an introduction to formal semantics (Cann
1993, Chierchia and McConnel-Ginet 1990, de Swart 1998, Heim and Kratzer
1998) and at least one to mentalist semantics in the Cognitive Grammar
framework (Ungerer and Schmidt 1996), and Cruse 1986 is the authoritative
source on traditional lexical semantics viewed from a contemporary theoretical
perspective. But many linguistics programs offer introductory semantics courses
designed to cover major topics in lexical semantics and some amount of
compositional semantics for students who may go on to specialize in either
formal or mentalist approaches, or in studies of other fields in linguistics in which
they have to be able to apply methods of mentalist or formalist semantics.

In this paper, I claim that the so-called present perfect puzzle is, in reality, a puzzle about the simple past. It is the latter, I argue, that shows a puzzling behavior, given that it can be used not only in definite contexts but also in seemingly indefinite ones. I employ the notions of time frame and specifiability to show how the obvious distinction between the two tenses in terms of temporal logic can be accounted for. I also propose that the past morpheme -ed be considered a kind of verb determiner which selects a temporal XP as a complement. Such complement can be (and usually is) expressed either in the sentence or in the larger discourse; however, it can also remain implicit, or covert.

My book, "Deflationism & Semantic Theories of Truth",  is available as a paperback via Amazon:

https://www.amazon.com/dp/0993594549/

https://www.amazon.co.uk/dp/0993594549/

To say that the sentence “snow is white” is true, is to say that snow is white, and nothing more.  Because of this apparent redundancy of the truth predicate for sentences, deflationists maintain that truth is a notion lacking in content and therefore not a worthy subject for philosophical analysis.  This book builds on the work of Jeffrey Ketland in demonstrating that semantic definitions of truth for formalised languages, in particular those of Alfred Tarski and Saul Kripke, are richer than their deflationary rivals, in the sense that they enable us to derive results that cannot be derived via deflationary theories.  This deductive power of semantic theories of truth suggests that truth is, contrary to the deflationists’ view, a substantive notion that warrants continued philosophical analysis.

This book explores relationships and maps out intersections between discussions on causation in three scientific disciplines: linguistics, philosophy, and psychology. The book is organized in five thematic parts, investigating connections between philosophical and linguistic studies of causation; presenting novel methodologies for studying the representation of causation; tackling central issues in syntactic and semantic representation of causal relations; and introducing recent advances in philosophical thinking on causation.

Beyond its thematic organization, readers will find several recurring topics throughout this book, such as the attempt to reduce causality to other non-causal terms; causal pluralism vs. one all-encompassing account for causation; causal relations pertaining to the mental as opposed to the physical realm, and more.
This collection also lays the foundation for questioning whether it is possible to evaluate available philosophical approaches to causation against the variety of linguistic phenomena ranging across diverse lexical and grammatical items, such as bound morphemes, prepositions, connectives, and verbs. Above all, it lays the groundwork for considering whether the fruits of the psychological-cognitive study of the perception of causal relations may contribute to linguistic and philosophical studies, and whether insights from linguistics can benefit the other two disciplines.

LENLS is an annual international workshop on formal syntax, semantics and pragmatics. It will be held as one of the workshops of the JSAI International Symposia on AI (JSAI-isAI2019) sponsored by the Japan Society for Artificial Intelligence (JSAI).

Слово “семантика” имеет много значений. Формальная семантика –сравнительно молодая наука, возникшая и развившаяся за последние 40 с лишним лет в результате совместной работы лингвистов, логиков и философов. Ключевую роль в ее истории сыграл американский логик и философ Ричард Монтегю, ученик Тарского. В ходе лекции Барбара Парти расскажет об основных идеях, повлиявших на развитие формальной семантики, и о том, как история этой дисциплины связана с фундаментальными проблемами лингвистической теории, философии и когнитивной науки..

One of the oldest concerns in linguistic theory is the characterization of grammatical categories, and the problem of how to capture their similarities and differences. Perhaps one of the most problematic cases identified in previous studies has been to find a non-parochial characterization of the relation between adjectives and verbs; participles are at the centre of the problem, because they show mixed morphosyntactic and semantic properties that connect them both with adjectives and verbs. The aim of this contribution is to summarize the main results and pending questions that the literature has identified in the study of the relation between adjectives, participles and verbs. We concentrate on two problems: their argument structure and their aspectual properties.

Das Vorlesungsskript führt in Anlehnung an das Lehrbuch "Semantics in Generative Grammar" (Irene Heim & Angelika Kratzer, 1998) in die formale  Semantik ein und richtet sich speziell an Philosoph_innen, die das Handwerk kompositionaler Semantik erlernen wollen. Mit vielen Übungsaufgaben (von Michael Matzer).

In this paper I discuss two types of adjectival modification in Polish, namely the semantics of prenominal and postnominal adjectives. I discuss different entailment patterns related to the placement of adjectival modifiers and the relation between adjectives in both positions and genericity. I postulate a unified intersective semantics for both prenominal and postnominal adjectives and argue that they are predicates denoting properties of objects and kinds respectively. I posit that the kind area is associated with the NP and in the process of semantic composition nouns first combine with postnominal modifiers and then with prenominal ones. The proposal is based on the syntactic analysis of Rutkowski and Progovac (2005) and the semantic framework of McNally and Boleda (2004).

Making use of Kayne's (2005, 2010) theory of light nouns, this paper argues that light nouns are part of (simple) names and that a mass-count distinction among light nouns explains the behavior of certain types of names in German as mass rather than count. The paper elaborates the role of light nouns with new generalizations regarding their linguistic behavior in quantificational and pronominal NPs, their selection of relative pronouns in German, and a general difference in the support of plural anaphora between English and German.

Resumen:
Wittgenstein, el filósofo más original del siglo XX, fue tomado erróneamente por un positivista. Pese a ello, la intención con la que Wittgenstein escribió el Tractatus era, en última instancia, una intención ética, que puede compendiarse bajo lo que el autor llama lo místico (das Mystische), que incluye la ética, la estética y la teoría de los valores. La preocupación por estas y otras cuestiones conexas, como la religión y el del sentido de la existencia, desempeñan un sordo papel central en el conjunto de su  pensamiento.
Y, si bien, según las propias tesis wittgensteinianas, las cuestiones éticas, no pueden ser respondidas y, en rigor, ni siquiera formuladas en el marco de la ciencia natural, esto no implica un menosprecio de “esta irrevocable tendencia del espíritu humano” a plantear tales cuestiones, sino más bien el reconocimiento de las limitaciones de nuestro lenguaje para dar cuenta de ellas. Ello se desprende de una afirmación central del Tractatus: “Nosotros sentimos que incluso si todas las posibles cuestiones científicas pudieran responderse, el problema de nuestra vida no habría sido más penetrado”.
Dr. Adolfo Vásquez Rocca
Palabras clave:
Filosofía Analítica, Wittgenstein, Tractatus, Lógica, Lenguaje, Mundo, Estética, Círculo de Viena,  Ética, Mística, Filosofía,  Religión, Psicoanálisis.
Referencia:
VÁSQUEZ ROCCA, Adolfo, “Wittgenstein; Mística, Filosofía y Silencio” – CONFERENCIA en 'SEMINARIO HUMANIDADES: ESTUDIOS ANTROPOLÓGICOS ACERCA DE LO DIVINO', Departamento de Artes y Humanidades, Facultad de Filosofía, Universidad Andrés Bello UNAB, Santiago, octubre, 2005. Publicada en Revista Observaciones Filosóficas – ISSN 0718-3712,  Sección Filosofía Contemporánea, Año 2006  http://www.observacionesfilosoficas.net/misticayfilosofia.html

In this paper I address a puzzle concerning different semantic interpretations of Polish NPs modified by basic cardinal numerals, e.g. dwaj studenci ('two students'), and NPs headed by numerals with the suffix-k-, e.g. dwójka studentów ('(a group of) two students'), with respect to distributivity and collectivity. The analysis uses formal semantic plurality framework of Landman (2000 a.o.).

Quantification forms a significant aspect of cross-linguistic research into both sentence structure and meaning. This book surveys research in quantification starting with the foundational work in the 1970s. It paints a vivid picture of generalized quantifiers and Boolean semantics. It explains how the discovery of diverse scope behavior in the 1990s transformed the view of quantification, and how the study of the internal composition of quantifiers has become central in recent years. It presents different approaches to the same problems, and links modern logic and formal semantics to advances in generative syntax. A unique feature of the book is that it systematically brings cross-linguistic data to bear on the theoretical issues, discussing French, German, Dutch, Hungarian, Russian, Japanese, Telugu (Dravidian), and Shupamem (Grassfield Bantu), and pointing to formal semantic literature involving quantification in around thirty languages.

Formal semantics and pragmatics as they have developed since the late 1960's have been shaped by fruitful inter-disciplinary collaboration among linguists, philosophers, and lo-gicians, among others, and in turn have had noticeable effects on developments in syntax, philosophy of language, computational linguistics, and cognitive science. In this paper I describe the environment in which formal semantics was born and took root, highlighting the differences in ways of thinking about natural language semantics in linguistics and in philosophy and logic. With Montague as a central but not solo player in the story, I reflect on crucial developments in the 1960's and 70's in linguistics and philosophy, and the growth of formal semantics and formal pragmatics from there. I discuss innovations, key players, and leading ideas that shaped the development of formal semantics and its relation to syntax, to prag-matics, and to the philosophy of language in its early years, and some central aspects of its early impact on those fields.