This work examines the waters of marine ports as unique integrated aquatic ecosystems. It regards marine ports as entities comprising components of natural and anthropogenic origin, including pelagic, periphytal and benthal subsystems. Using selected Black and Azov Sea ports as examples, the book discusses the hydrodynamics and water exchange, which are weakened in ports compared with open coastal zones. It reflects consequences of the presence of hydrobionts and the accumulation of organic matter, which are promoted by the variety of hard substrata and the absence of fishery. The book is divided into five main chapters. The first chapter describes the general characteristics of the marine ports at the northern coast of the Black and Azov Seas and their shipping channels. Chapters 2 to 4 discuss the main abiotic and biotic peculiarities of the pelagial, periphytal and benthal subsystems of those marine ports, and chapter 5 deals with tropho-dynamic processes in their ecosystems. A concluding section reflects recommendations how the ecosystems of ports in non-tidal seas may be ameliorated.

2 The authors of these issues involve not only mathematicians, but also speci alists in (mathematical) physics and computer sciences. So here the reader will find different points of view and approaches to the considered field. A. M. VINOGRADOV 3 Acta Applicandae Mathematicae 15: 3-21, 1989. (c) 1989 Kluwer Academic Publishers. Symmetries and Conservation Laws of Partial Differential Equations: Basic Notions and Results A. M. VINOORADOV Department of Mathematics, Moscow State University, 117234, Moscow, U. S. S. R. (Received: 22 August 1988) Abstract. The main notions and results which are necessary for finding higher symmetries and conservation laws for general systems of partial differential equations are given. These constitute the starting point for the subsequent papers of this volume. Some problems are also discussed. AMS subject classifications (1980). 35A30, 58005, 58035, 58H05. Key words. Higher symmetries, conservation laws, partial differential equations, infinitely prolonged equations, generating functions. o. Introduction In this paper we present the basic notions and results from the general theory of local symmetries and conservation laws of partial differential equations. More exactly, we will focus our attention on the main conceptual points as well as on the problem of how to find all higher symmetries and conservation laws for a given system of partial differential equations. Also, some general views and perspectives will be discussed."

The study of the kinematics and dynamics of machines lies at the very core of a mechanical engineering background. Although tremendous advances have been made in the computational and design tools now available, little has changed in the way the subject is presented, both in the classroom and in professional references.

Fundamentals of Kinematics and Dynamics of Machines and Mechanisms brings the subject alive and current. The author's careful integration of Mathematica software gives readers a chance to perform symbolic analysis, to plot the results, and most importantly, to animate the motion. They get to "play" with the mechanism parameters and immediately see their effects. A CD-ROM packaged with the book contains Mathematica-based programs for suggested design projects.

As useful as Mathematica is, however, a tool should not interfere with but enhance one's grasp of the concepts and the development of analytical skills. The author ensures this with his emphasis on the understanding and application of basic theoretical principles, unified approach to the analysis of planar mechanisms, and introduction to vibrations and rotordynamics.

Metamaterials and plasmonics are cross-disciplinary fields that are emerging into the mainstream of many scientific areas. Examples of scientific and technical fields which are concerned are electrical engineering, micro- and nanotechnology, microwave engineering, optics, optoelectronics, and semiconductor technologies. In plasmonics, the interplay between propagating electromagnetic waves and free-electron oscillations in materials are exploited to create new components and applications. On the other hand, metamaterials refer to artificial composites in which small artificial elements, through their collective interaction, creates a desired and unexpected macroscopic response function that is not present in the constituent materials.

This book charts the state of the art of these fields. In May 2008, world-leading experts in metamaterials and plasmonics gathered into a NATO Advanced Research Workshop in Marrakech, Morocco. The present book contains extended versions of 22 of the presentations held in the workshop, covering the general aspects of the field, as well as design and modelling questions of plasmonics and metamaterials, fabrication issues, and applications like absorbers and antennas.

The digital and increasingly digitised world is shaped by the interplay of new technological opportunities and ubiquitous societal trends. Both lead to drastic changes facing artificial intelligence (AI), cryptocurrencies and block-chain technologies, internet of things, technology-based surveillance, and other disruptive innovations. These developments facilitate the rise of the sharing economy and open for a variety of new entrepreneurial opportunities that businesses can take up. The novel entrepreneurial opportunities, however, imply a paradigmatic shift in the understanding of entrepreneurship. This book combines digital entrepreneurship with the sharing economy. It presents cutting-edge research for scholars and practitioners interested in either one of the topics - digital entrepreneurship or sharing economy - or their connection. The book addresses three major ways to become entrepreneurial in the sharing economy: digital entrepreneurship through creating novel sharing-economy platforms; technology entrepreneurship through the exploitation of sharing-economy platforms; and business model innovation or business model change influenced by the sharing economy. The book also highlights governance questions on digital entrepreneurship in the sharing economy, which are highly relevant for businesses, the economy, and society. The book will be of interested to researchers, academics, and students in the field of business and entrepreneurship, with a special focus on digital entrepreneurship.

The emergence of new platform business models, notably the sharing economy, is impacting the economy in various ways, altering the structure of many industries, and raising a number of economic and political issues. This book investigates the widespread influence of the sharing economy on businesses and society, as well as examining its underpinning economic principles and development. This volume presents an exhaustive review of the existing knowledge on the sharing economy and addresses several major areas of concern for incumbent businesses. It also explains the business models for those who are interested in embarking on their own ventures and provides an excellent source for further research. It takes an in-depth look at controversial labour policies, such as using labour as self-employed contractors or using regulatory grey areas to expand in markets. It is highly multidisciplinary, establishing links between economics, finance, marketing and consumer behaviour. This contribution on the sharing economy will enable researchers and graduate and doctoral students to expand and improve their understanding of this topic and identify new research problems in all of these areas. The book will also appeal to policy makers, regional and local government decision makers, and those interested in labour markets transformation.

Recent advances in our understanding of complex composite media, especially chiral media for microwave applications, suggest the feasibility of creating novel materials with unusual properties and the possibility of constructing new microwave devices using such materials. The emphasis of the book is on bi-anisotropic materials, whose most interesting feature is the magnetoelectric interaction of the fields. The materials are expected to supply useful applications in radar technology, aerospace, microwave engineering, manufacturing technology, etc., such as absorbers for low-reflectivity shields, reciprocal phase shifters, polarization transformers. The first experiments with artificial bi-anisotropic media have been successfully carried out.

The digital and increasingly digitised world is shaped by the interplay of new technological opportunities and ubiquitous societal trends. Both lead to drastic changes facing artificial intelligence (AI), cryptocurrencies and block-chain technologies, internet of things, technology-based surveillance, and other disruptive innovations. These developments facilitate the rise of the sharing economy and open for a variety of new entrepreneurial opportunities that businesses can take up. The novel entrepreneurial opportunities, however, imply a paradigmatic shift in the understanding of entrepreneurship. This book combines digital entrepreneurship with the sharing economy. It presents cutting-edge research for scholars and practitioners interested in either one of the topics - digital entrepreneurship or sharing economy - or their connection. The book addresses three major ways to become entrepreneurial in the sharing economy: digital entrepreneurship through creating novel sharing-economy platforms; technology entrepreneurship through the exploitation of sharing-economy platforms; and business model innovation or business model change influenced by the sharing economy. The book also highlights governance questions on digital entrepreneurship in the sharing economy, which are highly relevant for businesses, the economy, and society. The book will be of interested to researchers, academics, and students in the field of business and entrepreneurship, with a special focus on digital entrepreneurship.

The study of the kinematics and dynamics of machines lies at the very core of a mechanical engineering background. Although tremendous advances have been made in the computational and design tools now available, little has changed in the way the subject is presented, both in the classroom and in professional references. Fundamentals of Kinematics and Dynamics of Machines and Mechanisms brings the subject alive and current. The author's careful integration of Mathematica software gives readers a chance to perform symbolic analysis, to plot the results, and most importantly, to animate the motion. They get to "play" with the mechanism parameters and immediately see their effects. The downloadable resources contain Mathematica-based programs for suggested design projects. As useful as Mathematica is, however, a tool should not interfere with but enhance one's grasp of the concepts and the development of analytical skills. The author ensures this with his emphasis on the understanding and application of basic theoretical principles, unified approach to the analysis of planar mechanisms, and introduction to vibrations and rotordynamics.

The emergence of new platform business models, notably the sharing economy, is impacting the economy in various ways, altering the structure of many industries, and raising a number of economic and political issues. This book investigates the widespread influence of the sharing economy on businesses and society, as well as examining its underpinning economic principles and development. This volume presents an exhaustive review of the existing knowledge on the sharing economy and addresses several major areas of concern for incumbent businesses. It also explains the business models for those who are interested in embarking on their own ventures and provides an excellent source for further research. It takes an in-depth look at controversial labour policies, such as using labour as self-employed contractors or using regulatory grey areas to expand in markets. It is highly multidisciplinary, establishing links between economics, finance, marketing and consumer behaviour. This contribution on the sharing economy will enable researchers and graduate and doctoral students to expand and improve their understanding of this topic and identify new research problems in all of these areas. The book will also appeal to policy makers, regional and local government decision makers, and those interested in labour markets transformation.

This is a developing area of modern probability theory, which has applications in many areas. This volume is devoted to the systematic study of results on large deviations in situations where Cramer's condition on the finiteness of exponential moments may not be satisfied

Unlocked Memories is a collection of memories that were shared by Russians who witnessed the German invasion of the Leningrad region in 1941. All were children or young people during World War Two and nearly all were natives of Luga, Oredezh, or villages that were clustered around these two towns. Each lived under German rule after the Leningrad region was overrun and occupied by the enemy. The authors collected these memories over a period of ten years. Many of the memories had been locked away for decades; some to spare others from embarrassment, some for reasons that concerned the subject's welfare of the welfare of a relative or friend, and others because it was too painful to reflect upon them. All were recorded chronologically and have been placed within a historical narrative.

Although the analysis of scattering for closed bodies of simple geometric shape is well developed, structures with edges, cavities, or inclusions have seemed, until now, intractable to analytical methods. This two-volume set describes a breakthrough in analytical techniques for accurately determining diffraction from classes of canonical scatterers with comprising edges and other complex cavity features. It is an authoritative account of mathematical developments over the last two decades that provides benchmarks against which solutions obtained by numerical methods can be verified. The first volume, Canonical Structures in Potential Theory, develops the mathematics, solving mixed boundary potential problems for structures with cavities and edges. The second volume, Acoustic and Electromagnetic Diffraction by Canonical Structures, examines the diffraction of acoustic and electromagnetic waves from several classes of open structures with edges or cavities. Together these volumes present an authoritative and unified treatment of potential theory and diffraction-the first complete description quantifying the scattering mechanisms in complex structures.

Although the analysis of scattering for closed bodies of simple geometric shape is well developed, structures with edges, cavities, or inclusions have seemed, until now, intractable to analytical methods. This two-volume set describes a breakthrough in analytical techniques for accurately determining diffraction from classes of canonical scatterers with comprising edges and other complex cavity features. It is an authoritative account of mathematical developments over the last two decades that provides benchmarks against which solutions obtained by numerical methods can be verified. The first volume, Canonical Structures in Potential Theory, develops the mathematics, solving mixed boundary potential problems for structures with cavities and edges. The second volume, Acoustic and Electromagnetic Diffraction by Canonical Structures, examines the diffraction of acoustic and electromagnetic waves from several classes of open structures with edges or cavities. Together these volumes present an authoritative and unified treatment of potential theory and diffraction-the first complete description quantifying the scattering mechanisms in complex structures.

This text includes coverage of asymptotic expansions taking into account the cases when the number of summands comparable with the sum is less than or equal to two and asymptotic expansions of the probabilities of large deviations and non-uniform estimates of remainders in CLT.

The Women of Izmaelovka documents the lives of seven women who are residents of a Siberian village located on the steppes of the Ural region. The village was turned into a collective farm in 1929. As the women reflect on their lives, they discuss significant events such as collectivization, Joseph Stalin's acts of repression, the Great Patriotic War, de-Stalinization, Nikita Khrushchev's agricultural programs, the Brezhnev years and the fall of the Communist Party. Various stages of the women's lives are explored, including the years of educational experiences, marriage, motherhood, and assigned work. The daily routines of domestic duties, activities in the Village Club, and village traditions are also discussed. Having little control of their destinies and sacrificing much in order to survive, the women endured long hours of tedious labor under difficult situations. They detail having worked as milkmaids, pig herders, tractor drivers, combine operators, nurses, librarians, and Village Club coordinators. The women describe the ideological influence that the Communist Party of the Soviet Union brought into Izmaelovka through socialist competitions, propaganda, and youth organizations. Arguing that this rigid indoctrination taught them to believe that honesty, hard work, and Communism would achieve a better life and society, the study examines the effects of the Communist ideology on the women who sacrificed everything for it.

Springer-Verlag has invited me to bring out my Selected Works. Being aware that Springer-Verlag enjoys high esteem in the scientific world as a reputed publisher, I have willingly accepted the offer. Immediately, I was faced with two problems. The first was that of acquaint ing the reader with the important stages in my scientific aetivities. For this purpose, I have included in the Selected Works eertain of my early works that have greatly influeneed my later studies. For the same reason, I have also in cluded in the book those works that contain the first, erude versions of the proofs for many of my basic theorems. The second problem was that of giving the reader the best possible opportunity to familiarize himself with the most important results and to learn to use my method. For this reason I have included the later improved versions of the proofs for my basic results, as weil as the monographs The Method of Trigo nometric Sums in Number Theory (Seeond Edition) and Special Variants of the Method of Trigonometric Sums."

Recent advances in our understanding of complex composite media, especially chiral media for microwave applications, suggest the feasibility of creating novel materials with unusual properties and the possibility of constructing new microwave devices using such materials. The emphasis of the book is on bi-anisotropic materials, whose most interesting feature is the magnetoelectric interaction of the fields. The materials are expected to supply useful applications in radar technology, aerospace, microwave engineering, manufacturing technology, etc., such as absorbers for low-reflectivity shields, reciprocal phase shifters, polarization transformers. The first experiments with artificial bi-anisotropic media have been successfully carried out.

If one dismisses the Prophetess Deborah who in her famous song after the victory over the Philistines sang "The mountains melted before the Lord" and her contemporary (on our time scale), the Egyptian Amenemhet, who designed the water clock, which was in fact the prototype of the capillary viscometer, the beginnings of modern rheology should be linked up with the works of the classics of natural sciences of the 19th century: J ames Clerk Maxwell, Lord Kelvin, and Ludwig Boltzmann, whose names are associated with the origination of the fundamental concepts of rheology. The founda tions of experimental rheology were also laid in the nineteenth century in the works of J. M. L. Poiseuille, T. Schwedoff, and others. The next step in the advancement of rheology dates back to the twenties of this century when E. C. Bingham, G. W. Scott-Blair, A. Nadai, and M. Reiner developed the fundamentals of the engineering approach to the technological properties of real materials, thereby outlining the numerous potential applications of rheology. The progress of polymer rheology was especially vigorous after World War II when polymeric materials found their way into industry and the home. Today, rheology is 60-70 per cent concerned with investigations of this kind of materials. Polymer rheology has evolved as an independent science over the last 10-15 years and is in its various aspects intimately entwined with molecular physics, continuum mechanics, and the processing of polymeric materials."

Oxygen binding proteins are large multi unit proteins ideally suited for the study of structure function relationships in biological molecules. This book, based on a Symposium at the Xth International Biophysics Congress in 1990, provides a synthesis of recent advances in our knowledge of invertebrate oxygen carriers such as hemoglobins, hemocyanins, and hemorythrins. Comprehensive reviews are combined with new research results of importance to all biochemists and molecular biologists interested in oxygen carriers in general, their gene structure and comparative biochemistry. Of particular value are the studies of invertebrate oxygen binding proteins which perform their function and have structures vastly different from the vertebrate hemoglobins and myoglobins, as well as numerous examples of modern molecular techniques as applied to research on this diverse group of proteins.

Since the early work of Gauss and Riemann, differential geometry has grown into a vast network of ideas and approaches, encompassing local considerations such as differential invariants and jets as well as global ideas, such as Morse theory and characteristic classes. In this volume of the Encyclopaedia, the authors give a tour of the principal areas and methods of modern differential geomerty. The book is structured so that the reader may choose parts of the text to read and still take away a completed picture of some area of differential geometry. Beginning at the introductory level with curves in Euclidian space, the sections become more challenging, arriving finally at the advanced topics which form the greatest part of the book: transformation groups, the geometry of differential equations, geometric structures, the equivalence problem, the geometry of elliptic operators. Several of the topics are approaches which are now enjoying a resurgence, e.g. G-structures and contact geometry. As an overview of the major current methods of differential geometry, EMS 28 is a map of these different ideas which explains the interesting points at every stop. The authors' intention is that the reader should gain a new understanding of geometry from the process of reading this survey.

2 The authors of these issues involve not only mathematicians, but also speci alists in (mathematical) physics and computer sciences. So here the reader will find different points of view and approaches to the considered field. A. M. VINOGRADOV 3 Acta Applicandae Mathematicae 15: 3-21, 1989. (c) 1989 Kluwer Academic Publishers. Symmetries and Conservation Laws of Partial Differential Equations: Basic Notions and Results A. M. VINOORADOV Department of Mathematics, Moscow State University, 117234, Moscow, U. S. S. R. (Received: 22 August 1988) Abstract. The main notions and results which are necessary for finding higher symmetries and conservation laws for general systems of partial differential equations are given. These constitute the starting point for the subsequent papers of this volume. Some problems are also discussed. AMS subject classifications (1980). 35A30, 58005, 58035, 58H05. Key words. Higher symmetries, conservation laws, partial differential equations, infinitely prolonged equations, generating functions. o. Introduction In this paper we present the basic notions and results from the general theory of local symmetries and conservation laws of partial differential equations. More exactly, we will focus our attention on the main conceptual points as well as on the problem of how to find all higher symmetries and conservation laws for a given system of partial differential equations. Also, some general views and perspectives will be discussed.

Metamaterials and plasmonics are cross-disciplinary fields that are emerging into the mainstream of many scientific areas. Examples of scientific and technical fields which are concerned are electrical engineering, micro- and nanotechnology, microwave engineering, optics, optoelectronics, and semiconductor technologies. In plasmonics, the interplay between propagating electromagnetic waves and free-electron oscillations in materials are exploited to create new components and applications. On the other hand, metamaterials refer to artificial composites in which small artificial elements, through their collective interaction, creates a desired and unexpected macroscopic response function that is not present in the constituent materials.

This book charts the state of the art of these fields. In May 2008, world-leading experts in metamaterials and plasmonics gathered into a NATO Advanced Research Workshop in Marrakech, Morocco. The present book contains extended versions of 22 of the presentations held in the workshop, covering the general aspects of the field, as well as design and modelling questions of plasmonics and metamaterials, fabrication issues, and applications like absorbers and antennas.

Since the early work of Gauss and Riemann, differential geometry has grown into a vast network of ideas and approaches, encompassing local considerations such as differential invariants and jets as well as global ideas, such as Morse theory and characteristic classes. In this volume of the Encyclopaedia, the authors give a tour of the principal areas and methods of modern differential geomerty. The book is structured so that the reader may choose parts of the text to read and still take away a completed picture of some area of differential geometry. Beginning at the introductory level with curves in Euclidian space, the sections become more challenging, arriving finally at the advanced topics which form the greatest part of the book: transformation groups, the geometry of differential equations, geometric structures, the equivalence problem, the geometry of elliptic operators. Several of the topics are approaches which are now enjoying a resurgence, e.g. G-structures and contact geometry. As an overview of the major current methods of differential geometry, EMS 28 is a map of these different ideas which explains the interesting points at every stop. The authors' intention is that the reader should gain a new understanding of geometry from the process of reading this survey.