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521.
This paper presents the results of quasi-static cyclic tests on six reinforced concrete (RC) walls performed at the ETH Zurich. These large-scale tests investigate the effect of different vertical reinforcement contents and different reinforcement ductility properties typical for Central Europe on the deformation behaviour of slender RC walls. The test data documenting the global and local behaviour of the test units is available online and can therefore serve as a reference point for the research community. The experimental results show the importance of the reinforcement content and the ductility properties of both the boundary and web reinforcement for the deformation behaviour of the walls. By comparing base curvatures derived from experimental data with curvatures obtained from section analysis, strain limits characterising different limit states in plastic hinge analysis are suggested. These strain limits can be used in the performance-based design and assessment of RC structural walls. 相似文献
522.
523.
A broad participation by stakeholders and an extensive reliance on expert advice are often seen as preconditions for a legitimate and successfully implemented renewable energy policy. However, we have lacked systematic data for testing this argument. This article’s contribution is to examine the actors who take part in the making of Swedish energy policy with the help of data on the composition of various committees of inquiry over the last twenty years (1988–2009). Swedish renewable energy policy is often characterised with words like “pioneering” and “forerunner”, suggesting that the policy-making process in this area engages many different experts and stakeholders. Our data give only some support to this argument. Results point to a noteworthy predominance of politicians, civil servants, and representatives of state agencies within the policy-process. Producers of uranium and fossils based energy have been engaged more often than producers of renewable energy. Experts have played a prominent role, but this is mostly due to the participation of expert bureaucrats rather than of scientists. The study suggests that a better understanding of the making of energy policy, both in Sweden and elsewhere, requires greater attention to the networks and role of various state employees. 相似文献
524.
Acknowledging an increased research interest into the success factors for young technology‐based firms in the last decade, the present study serves two main purposes. First, we aim at developing a comprehensive concept of functional management competence in young technology‐based firms. Functional management competence covers the understanding of and proficiency in managing specific functional tasks ( Katz, 1974 ). As we focus on young technology‐based firms, it is suggested that marketing, financial and technology management tasks are at the core of functional management competence. Second, we aim at delineating and validating an appropriate measurement model for functional management competence. In order to test the model's nomological validity, we investigate the impact of functional management competence on firm growth. Therefore, building on established firm development approaches, we propose a phase model for the development of young technology‐based firms. Our study builds upon data from 212 young technology‐based firms in the field of microtechnology, nanotechnology, electronics, optics and lasers. We use formative measurement models to establish valid and reliable constructs and a path model based on partial least squares modelling to investigate the performance effects. The results suggest that functional management competences generally are significant drivers of firm development speed. In particular, technology and marketing management competences are shown to impact development speed. While technology management competence is positively driving development speed, the marketing management competence impact on speed is mediated by competitive advantage of the new products developed by young technology‐based firms. Financial management competence has no significant link to firm development speed. 相似文献
525.
Kim YH Marcus K Grinberg LT Goehler H Wiltfang J Stephan C Eisenacher M Hardt T Martens L J Dunn M Park YM Meyer HE 《Proteomics. Clinical applications》2009,3(9):1012-1016
The HUPO Brain Proteome Project (HUPO BPP) held its 11th workshop in Kolymbari on March 3, 2009. The principal aim of this project is to obtain a better understanding of neurodiseases and ageing, with the ultimate objective of discovering prognostic and diagnostic biomarkers, in addition to the development of novel diagnostic techniques and new medications. The attendees came together to discuss sub-project progress in the clinical neuroproteomics of human or mouse models of Alzheimer's and Parkinson's disease, and to define the needs and guidelines required for more advanced proteomics approaches. With the election of new steering committees, the members of the HUPO BPP elaborated an actual plan promoting activities, outcomes, and future directions of the HUPO BPP to acquire new funding and new participants. 相似文献
526.
Despite the acknowledged key role of leaders for psychosocial work environment, few studies focus on how leaders can decrease work-related stress. To gain deeper knowledge of leaders' perceptions and strategies for dealing with their own and their subordinates' stress in public human service organisations (HSO), qualitative interviews were made with leaders from hospitals and regional social insurance offices (n=21), and analysed in line with grounded theory method. The leaders handled subordinates' stress and perceived leadership demands by acting as shock absorber (core category) and used strategies characterised as leading in continuous change whilst maintaining trustworthiness. To cope with their own stress from perceived leadership demands, they tried to sustain their own integrity (core category) by either identifying with or distancing themselves from the leader role. The strategies for dealing with leaders' own and subordinates' exposures to stressors was pervaded by perceived leadership demands and are probably influencing each other. Supportive structures and improved communication about everyday dilemmas seem to be needed in order, not just to prevent stress reactions, but to improve the basic conditions for practicing leadership in HSO. 相似文献
527.
Potthoff SA Sitek B Stegbauer J Schulenborg T Marcus K Quack I Rump LC Meyer HE Stühler K Vonend O 《Proteomics. Clinical applications》2008,2(7-8):1127-1139
Adequate kidney function is crucial in sustaining vertebrate homeostasis. Certain diseases can diminish renal function and lead to end-stage renal disease. Diabetes mellitus and hypertension are the main causes of glomerulosclerosis and albuminuria in adults. The molecular mechanisms that trigger these maladaptive changes are still unsatisfyingly described. We previously introduced 2-D DIGE in combination with focused tissue isolation methods to analyze protein expression in glomeruli. Glomeruli, the crucial compartments in albuminuric renal diseases, were extracted using magnetic particles from subtotally nephrectomized FVB mice (n?=?6); this 5/6 nephrectomy in FVB mice is a model of chronic kidney disease. Analysis of protein expression levels from glomerular protein lysates was performed using 2-D DIGE and compared with glomerular protein lysates from mice that underwent sham surgery. The comparison of about 2100 detectable spots between both groups revealed 48 protein spots that showed significant differential expression. Of those, 33 proteins could be identified using nanoLC-ESI MS. The metalloproteinase meprin 1 alpha, the beta galactoside-binding-lectin galectin-1 and dimethylarginine dimethylaminohydrolase 1, a key enzyme in NO metabolism, were found to be differentially regulated, thus implying a role in the pathogenesis and pathophysiology of progressive kidney disease. In conclusion, 2-D DIGE protein analysis of smallest sample sizes from specific organ compartments provides focused protein expression results, which help in gaining an understanding of the molecular mechanisms of chronic kidney disease. 相似文献
528.
Despite much research on machine translation (MT) evaluation, there is surprisingly little work that directly measures users’ intuitive or emotional preferences regarding different types of MT errors. However, the elicitation and modeling of user preferences is an important prerequisite for research on user adaptation and customization of MT engines. In this paper we explore the use of conjoint analysis as a formal quantitative framework to assess users’ relative preferences for different types of translation errors. We apply our approach to the analysis of MT output from translating public health documents from English into Spanish. Our results indicate that word order errors are clearly the most dispreferred error type, followed by word sense, morphological, and function word errors. The conjoint analysis-based model is able to predict user preferences more accurately than a baseline model that chooses the translation with the fewest errors overall. Additionally we analyze the effect of using a crowd-sourced respondent population versus a sample of domain experts and observe that main preference effects are remarkably stable across the two samples. 相似文献
529.
Modelling Approaches for Inelastic Behaviour of RC Walls: Multi-level Assessment and Dependability of Results 总被引:1,自引:0,他引:1
Jo?o?Pacheco?AlmeidaEmail author Danilo?Tarquini Katrin?Beyer 《Archives of Computational Methods in Engineering》2016,23(1):69-100
The severe damage and collapse of many reinforced concrete (RC) wall buildings in the recent earthquakes of Chile (2010) and New Zealand (2011) have shown that RC walls did not perform as well as required by the modern codes of both countries. It seems therefore appropriate to intensify research efforts towards more accurate simulations of damage indicators, in particular local engineering demand parameters such as material strains, which are central to the application of performance-based earthquake engineering. Potential modelling improvements will necessarily build on a thorough assessment of the limitations of current state-of-the-practice simulation approaches for RC wall buildings. This work compares different response parameters obtained from monotonic analyses of RC walls using numerical tools that are commonly employed by researchers and specialized practitioners, namely: plastic hinge analyses, distributed plasticity models, and shell element models. It is shown that a multi-level assessment—wherein both the global and local levels of the response are jointly addressed during pre- and post-peak response—is fundamental to define the dependability of the results. The displacement demand up to which the wall response can be predicted is defined as the first occurrence between the attainment of material strain limits and numerical issues such as localization. The present work also presents evidence to discourage the application of performance-based assessment of RC walls relying on non-regularized strain EDPs. 相似文献
530.