Operator Functional State


Book Description




Operator Functional State


Book Description

The term `operator functional state' (OFS) acknowledges the intrinsic relationship between human task performance and the background state of the individual. Although central to an understanding of all aspects of performance, OFS, as its name implies, is of particular relevance to the behavior of operators of industrial control processes - chemical and nuclear plants, aviation, air traffic control, shipping, railways. The demands of managing complex control systems, particularly those that have safety-critical features, mean that operators cannot usually relax when they feel tense, or take breaks when they are tired. Instead, they must sustain high levels of task-directed effort for long periods, giving rise to strain, fatigue and unwanted after effects of work. The OFS approach recognizes the active nature of this adaptation to work goals and personal state, and argues for a methodology based on the necessity of examining the relationship between these processes under task conditions. The relationships between workload, effort, performance and fatigue, and the use of psychophysiological methods to investigate them, are at the heart of research in this area. Such issues are strongly represented in the papers that make up the present volume, which are based on the proceedings of a NATO Advanced Research Workshop (ARW).




Skrzydła nad Arktykiem


Book Description







Linear Functional Equations. Operator Approach


Book Description

In this book we shall study linear functional equations of the form m bu(x) == Lak(X)U(Qk(X)) = f(x), (1) k=l where U is an unknown function from a given space F(X) of functions on a set X, Qk: X -+ X are given mappings, ak and f are given functions. Our approach is based on the investigation of the operators given by the left-hand side of equa tion (1). In what follows such operators will be called functional operators. We will pay special attention to the spectral properties of functional operators, first of all, to invertibility and the Noether property. Since the set X, the space F(X), the mappings Qk and the coefficients ak are arbitrary, the class of operators of the form (1) is very rich and some of its individ ual representatives are related with problems arising in various areas of mathemat ics and its applications. In addition to the classical theory of functional equations, among such areas one can indicate the theory of functional-differential equations with deviating argument, the theory of nonlocal problems for partial differential equations, the theory of boundary value problems for the equation of a vibrating string and equations of mixed type, a number of problems of the general theory of operator algebras and the theory of dynamical systems, the spectral theory of au tomorphisms of Banach algebras, and other problems.




The Handbook of Operator Fatigue


Book Description

Fatigue is a recognized problem in many facets of the human enterprise. It is not confined to any one area of activity but enters all situations in which humans have to perform for extended intervals of time. Most problematic are the circumstances in which obligatory action is continuous and the results of failure are evidently serious or even catastrophic. Therefore, the modern media especially highlights fatigue-related failures in industries such as transportation, materials processing and healthcare. It can be, and indeed is, no coincidence that most of the spectacular failures in process control that have resulted in the world's largest industrial accidents have occurred in the small hours of the morning when the circadian rhythm is lowest and operator fatigue itself peaks. While there have been legislative efforts made at state, federal and international levels to regulate working hours of employees, the appropriate implementation of such legislation is still a long way off. The Handbook of Operator Fatigue provides a comprehensive account of the subject to serve as the definitive reference work for researchers, students and practitioners alike. The volume features 30 chapters written by experts from around the world to address each important facet of fatigue, including: the scale of the fatigue problem (Section I), the nature of fatigue (Section II), how to assess fatigue (Section III), the impact of fatigue on health (Section IV), fatigue in the workplace (Section V), the neurological basis of fatigue (VI), sleep disorders (VII), and the design of countermeasures to fatigue (VIII).




International Encyclopedia of Ergonomics and Human Factors - 3 Volume Set


Book Description

The first encyclopedia in the field, the International Encyclopedia of Ergonomics and Human Factors provides a comprehensive and authoritative compendium of current knowledge on ergonomics and human factors. It gives specific information on concepts and tools unique to ergonomics. About 500 entries, published in three volumes and on CD-ROM, are pre




State Spaces of Operator Algebras


Book Description

The topic of this book is the theory of state spaces of operator algebras and their geometry. The states are of interest because they determine representations of the algebra, and its algebraic structure is in an intriguing and fascinating fashion encoded in the geometry of the state space. From the beginning the theory of operator algebras was motivated by applications to physics, but recently it has found unexpected new applica tions to various fields of pure mathematics, like foliations and knot theory, and (in the Jordan algebra case) also to Banach manifolds and infinite di mensional holomorphy. This makes it a relevant field of study for readers with diverse backgrounds and interests. Therefore this book is not intended solely for specialists in operator algebras, but also for graduate students and mathematicians in other fields who want to learn the subject. We assume that the reader starts out with only the basic knowledge taught in standard graduate courses in real and complex variables, measure theory and functional analysis. We have given complete proofs of basic results on operator algebras, so that no previous knowledge in this field is needed. For discussion of some topics, more advanced prerequisites are needed. Here we have included all necessary definitions and statements of results, but in some cases proofs are referred to standard texts. In those cases we have tried to give references to material that can be read and understood easily in the context of our book.




Operator Theory in Function Spaces


Book Description

This book covers Toeplitz operators, Hankel operators, and composition operators on both the Bergman space and the Hardy space. The setting is the unit disk and the main emphasis is on size estimates of these operators: boundedness, compactness, and membership in the Schatten classes. Most results concern the relationship between operator-theoretic properties of these operators and function-theoretic properties of the inducing symbols. Thus a good portion of the book is devoted to the study of analytic function spaces such as the Bloch space, Besov spaces, and BMOA, whose elements are to be used as symbols to induce the operators we study. The book is intended for both research mathematicians and graduate students in complex analysis and operator theory. The prerequisites are minimal; a graduate course in each of real analysis, complex analysis, and functional analysis should sufficiently prepare the reader for the book. Exercises and bibliographical notes are provided at the end of each chapter. These notes will point the reader to additional results and problems. Kehe Zhu is a professor of mathematics at the State University of New York at Albany. His previous books include Theory of Bergman Spaces (Springer, 2000, with H. Hedenmalm and B. Korenblum) and Spaces of Holomorphic Functions in the Unit Ball (Springer, 2005). His current research interests are holomorphic function spaces and operators acting on them.




Geometry of State Spaces of Operator Algebras


Book Description

In this book we give a complete geometric description of state spaces of operator algebras, Jordan as well as associative. That is, we give axiomatic characterizations of those convex sets that are state spaces of C*-algebras and von Neumann algebras, together with such characterizations for the normed Jordan algebras called JB-algebras and JBW-algebras. These non associative algebras generalize C*-algebras and von Neumann algebras re spectively, and the characterization of their state spaces is not only of interest in itself, but is also an important intermediate step towards the characterization of the state spaces of the associative algebras. This book gives a complete and updated presentation of the character ization theorems of [10]' [11] and [71]. Our previous book State spaces of operator algebras: basic theory, orientations and C*-products, referenced as [AS] in the sequel, gives an account of the necessary prerequisites on C*-algebras and von Neumann algebras, as well as a discussion of the key notion of orientations of state spaces. For the convenience of the reader, we have summarized these prerequisites in an appendix which contains all relevant definitions and results (listed as (AI), (A2), ... ), with reference back to [AS] for proofs, so that this book is self-contained.