Localized waves in optical systems with periodic dispersion and nonlinearity management

We overview our recent developments in the theory of dispersion-managed (DM) solitons within the context of optical applications. First, we present a class of localized solutions with a period multiple to that of the standard DM soliton in the nonlinear Schrödinger equation with periodic variations of the dispersion. In the framework of a reduced ordinary differential equation-based model, we discuss the key features of these structures, such as a smaller energy compared to traditional DM solitons with the same temporal width. Next, we present new results on dissipative DM solitons, which occur in the context of mode-locked lasers. By means of numerical simulations and a reduced variational model of the complex Ginzburg-Landau equation, we analyze the influence of the different dissipative processes that take place in a laser.

Enhancing student learning experience through a novel electronic coursework assessment and feedback management system

Recent National Student Surveys revealed that many U.K. university students are dissatisfied with the timeliness and usefulness of the feedback received from their tutors. Ensuring timeliness in marking often results in a reduction in the quality of feedback. In Computer Science where learning relies on practising and learning from mistakes, feedback that pin-points errors and explains means of improvement is important to achieve a good student learning experience. Though suitable use of Information and Communication Technology should alleviate this problem, existing Virtual Learning Environments and e-Assessment applications such as Blackboard/WebCT, BOSS, MarkTool and GradeMark are inadequate to support a coursework assessment process that promotes timeliness and usefulness of feedback while maintaining consistency in marking involving multiple tutors. We have developed a novel Internet application, called eCAF, for facilitating an efficient and transparent coursework assessment and feedback process. The eCAF system supports detailed marking scheme editing and enables tutors to use such schemes to pin-point errors in students' work so as to provide helpful feedback efficiently. Tutors can also highlight areas in a submitted work and associate helpful feedback that clearly links to the identified mistakes and the respective marking criteria. In light of the results obtained from a recent trial of eCAF, we discuss how the key features of eCAF may facilitate an effective and efficient coursework assessment and feedback process.

Assessing the efficacy of structural merger remedies:choosing between theories of harm?

Previous empirical assessments of the effectiveness of structural merger remedies have focused mainly on the subsequent viability of the divested assets. Here, we take a different approach by examining how competitive are the market structures which result from the divestments. We employ a tightly specified sample of markets in which the European Commission (EC) has imposed structural merger remedies. It has two key features: (i) it includes all mergers in which the EC appears to have seriously considered, simultaneously, the possibility of collective dominance, as well as single dominance; (ii) in a previous paper, for the same sample, we estimated a model which proved very successful in predicting the Commission’s merger decisions, in terms of the market shares of the leading firms. The former allows us to explore the choices between alternative theories of harm, and the latter provides a yardstick for evaluating whether markets are competitive or not – at least in the eyes of the Commission. Running the hypothetical post-remedy market shares through the model, we can predict whether the EC would have judged the markets concerned to be competitive, had they been the result of a merger rather than a remedy. We find that a significant proportion were not competitive in this sense. One explanation is that the EC has simply been inconsistent – using different criteria for assessing remedies from those for assessing the mergers in the first place. However, a more sympathetic – and in our opinion, more likely – explanation is that the Commission is severely constrained by the pre-merger market structures in many markets. We show that, typically, divestment remedies return the market to the same structure as existed before the proposed merger. Indeed, one can argue that any competition authority should never do more than this. Crucially, however, we find that this pre-merger structure is often itself not competitive. We also observe an analogous picture in a number of markets where the Commission chose not to intervene: while the post-merger structure was not competitive, nor was the pre-merger structure. In those cases, however, the Commission preferred the former to the latter. In effect, in both scenarios, the EC was faced with a no-win decision. This immediately raises a follow-up question: why did the EC intervene for some, but not for others – given that in all these cases, some sort of anticompetitive structure would prevail? We show that, in this sample at least, the answer is often tied to the prospective rank of the merged firm post-merger. In particular, in those markets where the merged firm would not be the largest post-merger, we find a reluctance to intervene even where the resulting market structure is likely to be conducive to collective dominance. We explain this by a willingness to tolerate an outcome which may be conducive to tacit collusion if the alternative is the possibility of an enhanced position of single dominance by the market leader. Finally, because the sample is confined to cases brought under the ‘old’ EC Merger Regulation, we go on to consider how, if at all, these conclusions require qualification following the 2004 revisions, which, amongst other things, made interventions for non-coordinated behaviour possible without requiring that the merged firm be a dominant market leader. Our main conclusions here are that the Commission appears to have been less inclined to intervene in general, but particularly for Collective Dominance (or ‘coordinated effects’ as it is now known in Europe as well as the US.) Moreover, perhaps contrary to expectation, where the merged firm is #2, the Commission has to date rarely made a unilateral effects decision and never made a coordinated effects decision.

Language and identity in englishes

Key features include: • Discussion of language in relation to various aspects of identity, such as those connected with nation and region, as well as in relation to social aspects such as social class and race. • A chapter on undertaking research that will equip students with appropriate research methods for their own projects. • An analysis of language and identity within the context of written as well as spoken texts. Language and Identity in Englishes examines the core issues and debates surrounding the relationship between English, language and identity. Drawing on a range of international examples from the UK, US, China and India, Clark uses both cutting-edge fieldwork and her own original research to give a comprehensive account of the study of language and identity. With its accessible structure, international scope and the inclusion of leading research in the area, this book is ideal for any student taking modules in language and identity or sociolinguistics.

Introduction : Islam and human resource management

Purpose – The purpose of this paper is to introduce this special issue on Islam and human resource management (HRM). Design/methodology/approach – The paper introduces the papers in this special issue, which further current understanding of the association between Islam and HRM, and HRM practices in Islamic countries. The papers debate whether it makes sense to talk about an Islamic HRM, and try to identify the key features of an Islamic HRM model that is substantially distinctive from existing normative models of HRM. Findings – The papers examine the impact of Islamic values on HRM practices and organisational outcomes, but more research is needed to gain a deeper understanding of the role Islam plays at the work place, and specifically how Islamic ideals, culture, values and norms are used in practice and implications thereof on workplace environment and overall organisational performance. Originality/value – The paper introduces the concept of Islam and human resource management.

The information security policy unpacked:a critical study of the content of university policies

Ensuring the security of corporate information, that is increasingly stored, processed and disseminated using information and communications technologies [ICTs], has become an extremely complex and challenging activity. This is a particularly important concern for knowledge-intensive organisations, such as universities, as the effective conduct of their core teaching and research activities is becoming ever more reliant on the availability, integrity and accuracy of computer-based information resources. One increasingly important mechanism for reducing the occurrence of security breaches, and in so doing, protecting corporate information, is through the formulation and application of a formal information security policy (InSPy). Whilst a great deal has now been written about the importance and role of the information security policy, and approaches to its formulation and dissemination, there is relatively little empirical material that explicitly addresses the structure or content of security policies. The broad aim of the study, reported in this paper, is to fill this gap in the literature by critically examining the structure and content of authentic information security policies, rather than simply making general prescriptions about what they ought to contain. Having established the structure and key features of the reviewed policies, the paper critically explores the underlying conceptualisation of information security embedded in the policies. There are two important conclusions to be drawn from this study: (1) the wide diversity of disparate policies and standards in use is unlikely to foster a coherent approach to security management; and (2) the range of specific issues explicitly covered in university policies is surprisingly low, and reflects a highly techno-centric view of information security management.

Human resource management:strategic and international perspectives

With a strong focus on employability, this new text treats international, strategic and contemporary issues as central to the study and practice of Human Resource Management. Covering the core curriculum, this book provides all the knowledge and tools you need to get the best possible grades and achieve great career success after university. Key Features •Skills and employability focus will help you to secure a job in the tough economic climate whether as an HRM specialist or as a line manager. •Debating HRM boxes will develop your critical thinking skills, valued by examiners and employers alike. •International and cross-cultural perspectives are woven into discussion and case studies to prepare you for the realities of the global workplace. •Contemporary and strategic issues such as ethics, justice and CSR are introduced early on to underpin and enhance your understanding of the core HRM functions. •Unique final part will ensure that your skills can be applied in a range of organisational settings including SMEs and the not-for-profit and voluntary sectors. •Mapped to the CIPD’s learning outcomes but with an emphasis on the role of line managers throughout. •Companion website includes full text journal articles, glossary and chapter podcasts

Casebook on contract law

Jill Poole's bestselling Casebook on Contract Law provides students with a comprehensive selection of case law which addresses all aspects of the subject encountered on undergraduate courses. Extracts have been chosen from a wide range of historical and contemporary cases to illustrate the reasoning processes of the courts and to show how legal principles are developed. The cases can be analysed and discussed independently while, taken as a whole, the chapters provide a sound understanding of the modern law of contract. Key features: * An introductory chapter provides valuable guidance on how to use a casebook to help you develop the essential skill of reading and analysing cases * Cases are accompanied by succinct author commentary designed to highlight the key elements of each case * The two colour text design distinguishes case extracts from author commentary ensuring the book is easy to use and navigate through The casebook is fully supported by an Online Resource Centre, which provides: * Exercises and guidance on reading cases * Self-test questions and answers * Guidance on how to answer problem-style questions * Updates

Textbook on contract law

Jill Poole's immensely popular Textbook on Contract Law has been guiding students through contract law for many years. The accessible writing style and focus on key principles and developments in contract law make this text a favourite with students and lecturers alike. The author places the law of contract clearly within its wider context before proceeding to provide detailed yet accessible treatment of all the key areas encountered when studying contract law. Key features: · Key points, illustrative examples and questions encourage a deeper understanding of the central facts and issues · Each chapter begins with a summary of key issues, providing an overview of key themes and points of law, and concludes with suggestions for further reading, guiding you towards the most relevant texts and articles · An attractive page design highlights headings, case summaries, case extracts and a variety of learning features, making navigation through the text easy Fully supported by an Online Resource Centre, which provides: Student Resources Regular updates on new legislation, cases, and other important developments Guidance on answering questions in contract law Self-test questions and answers linked with Casebook on Contract Law Lecturer Resources A test bank of 300 multiple choice questions with answers and feedback

Random distributed feedback fibre lasers

The concept of random lasers exploiting multiple scattering of photons in an amplifying disordered medium in order to generate coherent light without a traditional laser resonator has attracted a great deal of attention in recent years. This research area lies at the interface of the fundamental theory of disordered systems and laser science. The idea was originally proposed in the context of astrophysics in the 1960s by V.S. Letokhov, who studied scattering with "negative absorption" of the interstellar molecular clouds. Research on random lasers has since developed into a mature experimental and theoretical field. A simple design of such lasers would be promising for potential applications. However, in traditional random lasers the properties of the output radiation are typically characterized by complex features in the spatial, spectral and time domains, making them less attractive than standard laser systems in terms of practical applications. Recently, an interesting and novel type of one-dimensional random laser that operates in a conventional telecommunication fibre without any pre-designed resonator mirrors-random distributed feedback fibre laser-was demonstrated. The positive feedback required for laser generation in random fibre lasers is provided by the Rayleigh scattering from the inhomogeneities of the refractive index that are naturally present in silica glass. In the proposed laser concept, the randomly backscattered light is amplified through the Raman effect, providing distributed gain over distances up to 100km. Although an effective reflection due to the Rayleigh scattering is extremely small (~0.1%), the lasing threshold may be exceeded when a sufficiently large distributed Raman gain is provided. Such a random distributed feedback fibre laser has a number of interesting and attractive features. The fibre waveguide geometry provides transverse confinement, and effectively one-dimensional random distributed feedback leads to the generation of a stationary near-Gaussian beam with a narrow spectrum. A random distributed feedback fibre laser has efficiency and performance that are comparable to and even exceed those of similar conventional fibre lasers. The key features of the generated radiation of random distributed feedback fibre lasers include: a stationary narrow-band continuous modeless spectrum that is free of mode competition, nonlinear power broadening, and an output beam with a Gaussian profile in the fundamental transverse mode (generated both in single mode and multi-mode fibres).This review presents the current status of research in the field of random fibre lasers and shows their potential and perspectives. We start with an introductory overview of conventional distributed feedback lasers and traditional random lasers to set the stage for discussion of random fibre lasers. We then present a theoretical analysis and experimental studies of various random fibre laser configurations, including widely tunable, multi-wavelength, narrow-band generation, and random fibre lasers operating in different spectral bands in the 1-1.6μm range. Then we discuss existing and future applications of random fibre lasers, including telecommunication and distributed long reach sensor systems. A theoretical description of random lasers is very challenging and is strongly linked with the theory of disordered systems and kinetic theory. We outline two key models governing the generation of random fibre lasers: the average power balance model and the nonlinear Schrödinger equation based model. Recently invented random distributed feedback fibre lasers represent a new and exciting field of research that brings together such diverse areas of science as laser physics, the theory of disordered systems, fibre optics and nonlinear science. Stable random generation in optical fibre opens up new possibilities for research on wave transport and localization in disordered media. We hope that this review will provide background information for research in various fields and will stimulate cross-disciplinary collaborations on random fibre lasers. © 2014 Elsevier B.V.

Textbook on contract law

Now in its 12th edition, Jill Poole's immensely popular Textbook on Contract Law has been guiding students through contract law for many years. The accessible writing style and focus on key principles and developments in contract law make this text a favourite with students and lecturers alike. The author places the law of contract clearly within its wider context before proceeding to provide a detailed yet accessible treatment of all the key areas encountered when studying contract law. Key features: -Each chapter begins with a summary of key issues, providing an overview of key themes and points of law, and concludes with suggestions for further reading, guiding you towards the most relevant texts and articles -Key points, illustrative examples and questions encourage a deeper understanding of the central facts and issues -Headings, case summaries and case extract boxes allow for easy navigation through the text

Multi-frequency segmental bio-impedance device:design, development and applications

Bio-impedance analysis (BIA) provides a rapid, non-invasive technique for body composition estimation. BIA offers a convenient alternative to standard techniques such as MRI, CT scan or DEXA scan for selected types of body composition analysis. The accuracy of BIA is limited because it is an indirect method of composition analysis. It relies on linear relationships between measured impedance and morphological parameters such as height and weight to derive estimates. To overcome these underlying limitations of BIA, a multi-frequency segmental bio-impedance device was constructed through a series of iterative enhancements and improvements of existing BIA instrumentation. Key features of the design included an easy to construct current-source and compact PCB design. The final device was trialled with 22 human volunteers and measured impedance was compared against body composition estimates obtained by DEXA scan. This enabled the development of newer techniques to make BIA predictions. To add a ‘visual aspect’ to BIA, volunteers were scanned in 3D using an inexpensive scattered light gadget (Xbox Kinect controller) and 3D volumes of their limbs were compared with BIA measurements to further improve BIA predictions. A three-stage digital filtering scheme was also implemented to enable extraction of heart-rate data from recorded bio-electrical signals. Additionally modifications have been introduced to measure change in bio-impedance with motion, this could be adapted to further improve accuracy and veracity for limb composition analysis. The findings in this thesis aim to give new direction to the prediction of body composition using BIA. The design development and refinement applied to BIA in this research programme suggest new opportunities to enhance the accuracy and clinical utility of BIA for the prediction of body composition analysis. In particular, the use of bio-impedance to predict limb volumes which would provide an additional metric for body composition measurement and help distinguish between fat and muscle content.

The CDU and party organisational change

This article undertakes an empirical analysis of the internal organisation of the CDU along four key dimensions. First, it discusses the model of the 'cartel party', identifying its key features and then setting out four key questions to pose in relation to the CDU's internal organisation, to see whether it approximates to the 'cartel' paradigm. The questions of whether a centralisation of power is visible; whether professionalisation has occurred; whether there has been the anticipated weakening in the power of party functionaries; and whether the CDU has become reliant upon state finances are then answered in the empirical section of the article, drawing upon the author's primary research. It concludes that the 'cartel party' thesis fails in significant respects accurately to reflect the CDU's modern organisation. This is of interest to scholars of the CDU, but also offers some insights on the way in which the cartel party thesis fails adequately to develop an accurate account of internal party organisational change, in particular underestimating the ability of internal actors to thwart reforms, and also the potential functional usefulness of a decentralised party organisation. © 2013 Association for the Study of German Politics.

A Two Layered Model for Evolving Web Resources

In this paper the key features of a two-layered model for describing the semantic of dynamical web resources are introduced. In the current Semantic Web proposal [Berners-Lee et al., 2001] web resources are classified into static ontologies which describes the semantic network of their inter-relationships [Kalianpur, 2001][Handschuh & Staab, 2002] and complex constraints described by logical quantified formula [Boley et al., 2001][McGuinnes & van Harmelen, 2004][McGuinnes et al., 2004], the basic idea is that software agents can use techniques of automatic reasoning in order to relate resources and to support sophisticated web application. On the other hand, web resources are also characterized by their dynamical aspects, which are not adequately addressed by current web models. Resources on the web are dynamical since, in the minimal case, they can appear or disappear from the web and their content is upgraded. In addition, resources can traverse different states, which characterized the resource life-cycle, each resource state corresponding to different possible uses of the resource. Finally most resources are timed, i.e. they information they provide make sense only if contextualised with respect to time, and their validity and accuracy is greatly bounded by time. Temporal projection and deduction based on dynamical and time constraints of the resources can be made and exploited by software agents [Hendler, 2001] in order to make previsions about the availability and the state of a resource, for deciding when consulting the resource itself or in order to deliberately induce a resource state change for reaching some agent goal, such as in the automated planning framework [Fikes & Nilsson, 1971][Bacchus & Kabanza,1998].

Models@run.time:foundations, applications, and roadmaps

Traditionally, research on model-driven engineering (MDE) has mainly focused on the use of models at the design, implementation, and verification stages of development. This work has produced relatively mature techniques and tools that are currently being used in industry and academia. However, software models also have the potential to be used at runtime, to monitor and verify particular aspects of runtime behavior, and to implement self-* capabilities (e.g., adaptation technologies used in self-healing, self-managing, self-optimizing systems). A key benefit of using models at runtime is that they can provide a richer semantic base for runtime decision-making related to runtime system concerns associated with autonomic and adaptive systems. This book is one of the outcomes of the Dagstuhl Seminar 11481 on models@run.time held in November/December 2011, discussing foundations, techniques, mechanisms, state of the art, research challenges, and applications for the use of runtime models. The book comprises four research roadmaps, written by the original participants of the Dagstuhl Seminar over the course of two years following the seminar, and seven research papers from experts in the area. The roadmap papers provide insights to key features of the use of runtime models and identify the following research challenges: the need for a reference architecture, uncertainty tackled by runtime models, mechanisms for leveraging runtime models for self-adaptive software, and the use of models at runtime to address assurance for self-adaptive systems.