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A Surrogate Model Assisted Evolutionary Algorithm for Computationally Expensive Design Optimization Problems with Discrete Variables
Get PDFReal-world computationally expensive design optimization problems with discrete variables pose challenges to surrogate-based optimization methods in terms of both efficiency and search ability. In this paper, a new method is introduced, called surrogate model-aware differential evolution with neighbourhood exploration, which has two phases. The first phase adopts a surrogate-based optimization method based on efficient surrogate model-aware search framework, the goal of which is to reach at least the neighbourhood of the global optimum. In the second phase, a neighbourhood exploration method for discrete variables is developed and collaborates with the first phase to further improve the obtained solutions. Empirical studies on various benchmark problems and a real-world network-on-chip design optimization problem show the combined advantages in terms of efficiency and search ability: when only a very limited number of exact evaluations are allowed, the proposed method is not slower than one of the most efficient methods for the targeted problem; when more evaluations are allowed, the proposed method can obtain results with comparable quality compared to standard differential evolution, but it requires only 1% to 30% of exact function evaluations
Implementing Competencies and their impact on Social Education
Get PDFoai:glyndwr.collections.crest.ac.uk:89This paper examines the benefits and problems of implementing a system of competencies, with particular reference to social education in the UK. It recognises the potential value of National Occupational Standards as a means of promoting public esteem and recognition by other professionals, providing a framework for the discussing and enhancing practice and a means of maintaining quality and standards. However, the narrow instrumental emphasis on outcomes involves a lack of emphasis on the process of learning, marginalises professional values and ignores the context in which learning takes place. Consequently National Occupational Standards are only useful when used in conjunction with a broad-based education and training programme, which encourages creative practice and innovation and is aimed at producing fully-reflective and self-critical practitioners
Attitudes and Values of Adolescent Europeans towards Europeanisation
Get PDFBased on original empirical data collected from adolescents in Europe (N=9003) this paper focuses on the lifeworlds of young people. It analyses negative and positive patterns of attitude and combines them with further concepts: first, personal life perspectives, various key values and political attitudes, second, religious attitudes towards church(es), religions, world views and religious education. Technically, the attitude towards Europe acts as the dependent variable whereas the remaining concepts are used as independent variables. The empirical results show Turkish and Polish adolescents are more critical of Europe than adolescents living in “old” Europe. Furthermore, the data show that those who have negative expectations about their personal futures and follow a more traditional religious world view are likely also to be Eurosceptical
CVs and interview techniques
No full textThis is an easy to read step-by-step chapter on CV writing and tips when attending interviews. It is mainly focussed upon Health and Social Care students but many of the tips and guidelines would be relevant to other University students
A dynamic NMR study of 1,2-metallotropic shifts in trimethylplatinum(IV) halide complexes of 3-methylpyridazine.
No full text3-Methylpyridazine (3-Mepydz) reacts with halogenotrimethylplatinum(IV), [PtXMe₃)₄], to afford complexes of type fac-[PtXMe₃(3-Mepydz)₂] (X = Cl, Br or I). In solution these complexes undergo 1,2-metallotropic shifts between the contiguous nitrogen donors producing different linkage isomers. Solution abundances of these ismers are strongly influenced by the steric effects of the 3-methyl group on the pyridazine ring, with the (1,1)-isomer always being predominant (≈ 95%). Activation energies for the fluxion were determined by variable temperature ¹H NMR spectroscopy, values of the (1,1) → (1,2) isomer shift being in the range 74–78 kJ mol⁻¹
Internet Plagiarism: A Survey and Case Study
Get PDFThis paper discusses the root causes of student plagiarism, particularly in Higher Education and particularly Interned-based. It considers the motivation of students, staff and administrators with their particular perspectives. It describes a case study currently in progress at Glyndŵr University in North Wales and reports preliminary results. Some pertinent observations and suggestions are offered in conclusion
Towards Finding Efficient Tools for Measuring the Tail Index and Intensity of Long-range Dependent Network Traffic
Get PDFMany researchers have discussed the effects of heavy-tailedness in network traffic patterns and shown that Internet traffic flows exhibit characteristics of self-similarity that can be explained by the heavy-tailedness of the various distributions involved. Self-similarity and heavy-tailedness are of great importance for network capacity planning purposes in which researchers are interested in developing analytical methods for analysing traffic characteristics. Designers of computing and telecommunication systems are increasingly interested in employing heavy-tailed distributions to generate workloads for use in simulation - although simulations employing such workloads may show unusual characteristics. Congested Internet situations, where TCP/IP buffers start to fill, show long-range dependent (LRD) self-similar chaotic behaviour. Such chaotic behaviour has been found to be present in Internet traffic by many researchers. In this context, the 'Hurst exponent', H, is used as a measure of the degree of long-range dependence. Having a reliable estimator can yield a good insight into traffic behaviour and may eventually lead to improved traffic engineering. In this paper, we describe some of the most useful mechanisms for estimating the tail index of Internet traffic, particularly for distributions having the power law observed in different contexts, and also the performance of the estimators for measuring the intensity of LRD traffic in terms of their accuracy and reliability
Elite Refereeing Performance:Developing a Modelfor Sport Science Support
Get PDFTo identify a framework for referee training and selection, based on the key areas of effective performance, we conducted content analyses on Rugby Football Union referee assessor reports, referee training materials, performance profiles from a group of English premier league referees, and a review of published research on sports officiating. The Cornerstones Performance Model of Refereeing emerged, overarched by the psychological characteristics of excellence (see McCaffrey & Orlick, 1989) and featuring four key areas; (a) knowledge and application of the law; (b) contextual judgment; (c) personality and management skills; and (d) fitness, positioning and mechanics. Focus group interviews confirmed the usefulness of the model as an assessment and training tool, which the RFU now use to develop referees throughout Englan
Research Issues in the Development of Advanced Mobile Web-Based Geospatial Information Services
Get PDFThis paper considers the development of the next generation of mobile web-based geospatial information services and the underlying research issues that need to be tackled. These include the human factors, (including device related issues and geosemantics), architectural issues and efficiency, complexity of processing and security issues
A Simplified Method for Optimising Sequentially Processed Access Control Lists
Get PDFAmong the various options for implementing Internet packet filters in the form of Access Control Lists (ACLs), is the intuitive – but potentially crude – method of processing the ACL rules in sequential order. Although such an approach leads to variable processing times for each packet matched against the ACL, it also offers the opportunity to reduce this time by reordering its rules in response to changing traffic characteristics. A number of heuristics exist for optimising rule order in sequentially processed ACLs and the most efficient of these can be shown to have a beneficial effect in a majority of cases and for ACLs with relatively small numbers of rules. This paper presents an enhancement to this algorithm by reducing part of its complexity. Although the simplification involved leads to an instantaneous lack of accuracy, the long-term trade-off between processing speed and performance can be seen, through experimentation, to be positive. This improvement, though small, is consistent and worthwhile and can be observed in the majority of cases