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1.
The format of cycling time trials in England, Wales and Northern Ireland, involves riders competing individually over several fixed race distances of 10–100 miles in length and using time constrained formats of 12 and 24 h in duration. Drawing on data provided by the national governing body that covers the regions of England and Wales, an analysis of six male competition record progressions was undertaken to illustrate its progression. Future forecasts are then projected through use of the Singular Spectrum Analysis technique. This method has not been applied to sport-based time series data before. All six records have seen a progressive improvement and are non-linear in nature. Five records saw their highest level of record change during the 1950–1969 period. Whilst new record frequency generally has reduced since this period, the magnitude of performance improvement has generally increased. The Singular Spectrum Analysis technique successfully provided forecasted projections in the short to medium term with a high level of fit to the time series data.  相似文献   
2.
In this paper a new integrated observer-based fault estimation and accommodation strategy for discrete-time piecewise linear (PWL) systems subject to actuator faults is proposed. A robust estimator is designed to simultaneously estimate the state of the system and the actuator fault. Then, the estimate of fault is used to compensate for the effect of the fault. By using the estimate of fault and the states, a fault tolerant controller using a PWL state feedback is designed. The observer-based fault-tolerant controller is obtained by the interconnection of the estimator and the state feedback controller. We show that separate design of the state feedback and the estimator results in the stability of the overall closed-loop system. In addition, the input-to-state stability (ISS) gain for the closed-loop system is obtained and a procedure for minimizing it is given. All of the design conditions are formulated in terms of linear matrix inequalities (LMI) which can be solved efficiently. Also, performance of the estimator and the state feedback controller are minimized by solving convex optimization problems. The efficiency of the method is demonstrated by means of a numerical example.  相似文献   
3.
Familial hypercholesterolemia (FH) is an autosomal dominant disorder of lipoprotein metabolism caused mainly by mutations in the low-density lipoprotein receptor (LDLR) and apolipoprotein B 100 (APOB) genes. Until now, the molecular basis of FH has been demonstrated in detail in many populations, but there is still very limited Molecular data concerning FH in Iran. The aim of this study was to characterize the LDLR and APOB gene mutations in an Iranian population. A total of 30 non-related Iranian possible FH subjects were studied. Diagnosis of FH was based on the Dutch Lipid Clinic Network diagnostic criteria. All samples were initially tested for three common APOB gene mutations including R3500Q, R3500 W and R3531C using PCR-RFLP assay. Subsequently, promoter and coding region of the LDLR gene was screened by PCR-SSCP analysis and positive results were confirmed by DNA sequencing. Four previously reported polymorphisms 1413G > A, 1725C > T, 1773T > C and 2140 + 5G > A were found in ~17% (5/30) of population studied. Moreover, no variation was found in APOB gene. Our data indicated that LDLR and APOB gene mutations have not contribution to possible FH in Iranian population studied here. However, we examined three common APOB mutations and LDLR in only 30 patients, and to determine the role of these genes in developing FH in Iran, more FH samples and populations needed to be investigated for the mutations of the related genes.  相似文献   
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This article explores an understanding of learning as authentic enquiry and language as a social practice of meaning construction as the theoretical perspectives underlying an educational initiation beyond mainstream tertiary language education. With a general ethnographic approach and relying on multiple data sources, we investigate critical practices of teaching medical English in an Iranian university and illustrate a contextualized instance of enquiry-based language learning that embodies enquiry and discovery in two senses: students’ research and learning about the content for oneself, and moving away from spoon-feeding views of academic language education to experience language in real social contexts. On this basis, we argue for stepping beyond predetermined content-based approaches to university language teaching and call for living the language that is being learned, which involves enquiring, experiencing, discovering, challenging, and owning it.  相似文献   
6.
The search for fairness in language testing is distinct from other areas of educational measurement as the object of measurement, that is, language, is part of the identity of the test takers. So, a host of issues enter the scene when one starts to reflect on how to assess people's language abilities. As the quest for fairness in language testing is still in its infancy, even the need for such a research has been controversial, with some (e.g., Davies, 2010) arguing that such research is entirely in vain. This paper will provide an overview of some of the issues involved. Special attention will be given to critical language testing (CLT) as it has had a large impact on language testing research. It will be argued that although CLT has been very effective in revealing the ideological and value implications of the constructs of focus in language testing, extremism in this direction is not justified.  相似文献   
7.
Although Richard Rorty's controversial thought has been the subject of many works, there has not been much discussion about his approach to cultural difference. The purpose of this article is to examine how Rorty sees cultural differences philosophically and how he deals with them politically. For him, rationality, morality and even the scope of moral responsibility towards others are defined in terms of solidarity with a particular community and ‘ethnocentrism’, rather than in terms of a universal and metaphysically derived set of criteria. It can be argued that since language, language games and values are mainly components of culture, the latter is one of the most significant communities with which Rorty is concerned, though he is not explicit about it. Nevertheless, Rorty does not think that the moral and philosophical significance of communities, particularly cultural communities, should be reflected in politics. The main argument of the article is that there is an unresolved tension in Rorty's thought between philosophical, moral and emotional attribution of significance to communities and arguably cultural communities, and a disregard for them in the political sphere. This paves the way for outlining an approach to cultural difference that is more just and even more in harmony with Rorty's own philosophy.  相似文献   
8.
Social informatics research offers insights into the relationship between information technologies and social contexts. However, the material roles of information technologies, and their interplay with the agentic work of social actors, have not been addressed. Drawing on a field study of 37 mobile knowledge workers, we examine the dual material roles (enabling and constraining) played by information technologies in their work practices. We also investigate how these workers exert agency by fashioning multiple information technologies into a functioning digital assemblage. Although information technologies provide consequential affordances that enable mobilization of work across spaces and times, they simultaneously present design-driven, local, organizational, and temporal technological constraints that require mobile knowledge workers to engage in “configuration work” to make information technologies function effectively. Building on a sociomaterial perspective, we further discuss the interplay of information technologies and work practices enacted by mobile knowledge workers, in which both human and technological agency are materialized.  相似文献   
9.
Measurement of optical properties of skin is an expanding and growing field of research. Recent studies have shown that the biological tissue, especially skin, changes the polarization state of the incident light. Using this property will enable the study of abnormalities and diseases that alter not only the light intensity but also its polarization state. In this paper we report an experimental study for measuring changes of polarization state of the light scattered from a phantom similar to a sample model of scattering skin. Using the notation of Stokes vector for the polarized light and Mueller matrix for the sample with its polarization properties, we have shown that some elements of the matrix were particularly sensitive to the changes of the polarization-altering physical properties of the scatterers within the phantom.   相似文献   
10.
Speaker variability is an important source of speech variations which makes continuous speech recognition a difficult task. Adapting automatic speech recognition (ASR) models to the speaker variations is a well-known strategy to cope with the challenge, Almost all such techniques focus on developing adaptation solutions within the acoustic models of the ASR systems. Although variations of the acoustic features constitute an important portion of the inter-speaker variations, they do not cover variations at the phonetic level. Phonetic variations are known to form an important part of variations which are influenced by both micro-segmental and suprasegmental factors. Inter-speaker phonetic variations are influenced by the structure and anatomy of a speaker's articulatory system and also his/her speaking style which is driven by many speaker background characteristics such as accent, gender, age, socioeconomic and educational class. The effect of inter-speaker variations in the feature space may cause explicit phone recognition errors. These errors can be compensated later by having appropriate pronunciation variants for the lexicon entries which consider likely phone misclassifications besides pronunciation. In this paper, we introduce speaker adaptive dynamic pronunciation models, which generate different lexicons for various speaker clusters and different ranges of speech rate. The models are hybrids of speaker adapted contextual rules and dynamic generalized decision trees, which take into account word phonological structures, rate of speech, unigram probabilities and stress to generate pronunciation variants of words. Employing the set of speaker adapted dynamic lexicons in a Farsi (Persian) continuous speech recognition task results in word error rate reductions of as much as 10.1% in a speaker-dependent scenario and 7.4% in a speaker-independent scenario.  相似文献   
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