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The growth of collaborative approaches to governance has resulted in increasingly complex policy and management landscapes, where actors are presented with ever‐increasing numbers of decision‐making venues they can participate in and actors they can collaborate with. Given that actors face constraints on their capacity to manage actor and venue relationships in such polycentric governance systems, we assume the marginal benefit of yet another relationship should begin to diminish at some level of engagement. Furthermore, we hypothesize that such capacity limitations are not static, but decrease as actors learn, develop skills, and formulate strategies for how to navigate complex polycentric systems more effectively. Drawing on the Ecology of Games framework, this article investigates two Swedish collaborative governance initiatives where a multitude of actors came together to address a range of different, but interrelated, policy issues and management tasks. The empirical findings suggest that actors’ capacities to successfully navigate polycentric governance arrangements increase as they gain experience and develop their networking skills. Our findings imply there is a need to balance increased complexity in polycentric systems with increased capacity, otherwise the overall effect of an ever‐increasing number of venues and actors could be collaborative fatigue and decreased abilities to address diverse governance challenges.  相似文献   
84.
Taking the case of defining “talent,” a term that has been widely used but its definitions differ by discipline, organization, policy sector, as well as over time, we demonstrate how the basic definition of a policy subject may affect policy design and the assessment of policy outcomes. We review how “talent” is defined in two sets of literature, talent management and migration studies, and find that definitions fall under one of two categories: binary (“talent” as qualities) or composite (“talent” as a relational concept). The implications of our findings are epistemological and ontological; the findings point to diverse epistemological effects of definitions through developments of indicators, as expected, and they also reveal the policy designers’ ontological starting points. Ontological perspectives are significant because they ultimately determine whether the policy assessments carried out differ in degrees or in kind. In the case of defining “talent,” this means determining which objectives the designers would set (e.g., recruiting vs. cultivating vs. introducing competition), the policy instrumentation for achieving the goals (migration measures vs. education vs. lifelong learning vs. human resource policy), and the type of assessment for measuring policy outcomes (single vs. multiple indicators, qualitative vs. quantitative).  相似文献   
85.
陈林烽 《东南文化》2016,(4):106-111
博物馆中的灯光艺术是每一位设计师必须面对的课题,任何一个主题展览的成功举办离不开展品的展示与表达,以及灯光的衬托与布局。主题展览灯光设计与运用的优劣程度,是衡量博物馆建设成功与否的重要标志。在展览艺术中,光要营造出让人舒适的感受,设计者要设计出令观众满意、舒适的光线和阴影。在目前LED灯具制造技术水平参差不齐的状况下,博物馆应谨慎推进灯光升级工作。灯与光的设计不仅是一种技术,更是一种艺术。光与影的设计发展历程揭示出,它已不仅着眼于探讨主题展览的展品本身,更在营造一种氛围,创造一件艺术作品。  相似文献   
86.
An important record of ground motion from a M6.4 earthquake occurring on May 1, 2003, at epicentral and fault distances of about 12 and 9 km, respectively, was obtained at a station near the city of Bingöl, Turkey. The maximum peak ground values of 0.55 g and 36 cm/s are among the largest ground-motion amplitudes recorded in Turkey. From simulations and comparisons with ground motions from other earthquakes of comparable magnitude, we conclude that the ground motion over a range of frequencies is unusually high. Site response may be responsible for the elevated ground motion, as suggested from analysis of numerous aftershock recordings from the same station. The mainshock motions have some interesting seismological features, including ramps between the P-and S-wave that are probably due to near- and intermediate-field elastic motions and strong polarisation oriented at about 39 degrees to the fault (and therefore not in the fault-normal direction). Simulations of motions from an extended rupture explain these features. The N10E component shows a high-amplitude spectral acceleration at a period of 0.15 seconds resulting in a site specific design spectrum that significantly overestimates the actual strength and displacement demands of the record. The pulse signal in the N10E component affects the inelastic spectral displacement and increases the inelastic displacement demand with respect to elastic demand for very long periods.  相似文献   
87.
Classification of earthquake strong ground motion (SGM) records is performed using fuzzy pattern recognition to exploit knowledge in the data that is utilised in a genetic algorithm (GA) search and scaling program. SGM records are historically treated as “fingerprints” of certain event magnitude and mechanism of faulting systems recorded at different distances on different soil types. Therefore, databases of SGM records of today present data of complex nature in high dimensions (many of the dimensions—or SGM parameters in time and frequency domain—are presently available from different archives). In this study, simple ground motion parameters were used but were combined and scaled nonlinearly such that the physical properties of the data could be preserved while reducing its dimensionality. The processed data was then analysed using fuzzy c-means (FCM) clustering method to explore the possibility of meaningfully representing earthquake SGM data in lower dimensions through finding subsets of mathematically similar vectors in a benchmark database. This representation can be used in practical applications and has a direct influence on the processes of synthesising ground motion records, identifying unknown ground motion parameters (e.g. soil type in this study), improving the quality of matching SGM records to design target spectra, and in rule generalisation for response. The results showed that the stochastic behaviour of earthquake ground motion records can be accurately simplified by having only a few of motion parameters. The very same parameters may also be utilised to derive unknown characteristics of the motion when the classification task on “training” records is performed carefully. The clusters are valid and stable in time and frequency domain and are meaningful even with respect to seismological features that were not included in the classification task.  相似文献   
88.
The development of alternative solutions for precast concrete buildings based on jointed ductile connections has introduced innovative concepts in the design of lateral-load resisting frame and wall systems. Particularly efficient is the hybrid system, where precast elements are connected via post-tensioning techniques and self-centring and energy dissipating properties are adequately combined to achieve the target maximum displacement with negligible residual displacements. In this contribution, the concept of hybrid system is extended to bridges as a viable and efficient solution for an improved seismic performance when compared with monolithic counterparts. Critical discussion on the cyclic behaviour of hybrid systems, highlighting the most significant parameters governing the response, is carried out.

The concept of a flexible seismic design (displacement-based) of hybrid bridge piers and systems is proposed and its reliability confirmed by quasi-static cyclic (push-pull) and nonlinear time-history analyses based on lumped plasticity numerical models.  相似文献   
89.
A large part of the building population in Switzerland is made of unreinforced masonry. For the assessment of the seismic risk the evaluation of the seismic vulnerability of existing unreinforced masonry buildings is therefore crucial. In this paper a method to evaluate existing buildings, which was developed for the earthquake scenario project for Switzerland, is briefly introduced and discussed in more detail for unreinforced masonry buildings. The method is based on a non-linear static approach where the seismic demand on the building is compared with the capacity of the building. In-plane and out-of-plane behaviour are considered. Comparisons with test results from model buildings show that the proposed method suitably forecasts the capacity of a building. Finally, a numerical example of the application of the method to a building in the city of Basel is given.  相似文献   
90.
A new nonlinear soil-structure interaction macroelement is presented. It models the dynamic behaviour of a shallow strip foundation under seismic action. Based on sub-structured methods, it takes into account the dynamic elastic effect of the infinite far field, and the material and geometrical nonlinear behaviour produced in the near field of the foundation. Effects of soil yielding below the foundation as well as uplift at the interface are considered. Through the concept of macro-element, the overall elastic and plastic behaviour in the soil and at the interface is reduced to its action on the foundation. The macro-element consists of a non linear joint element, expressed in the three degrees of freedom of the strip foundation, reflecting the limited bearing capacity of the foundation. This model provides a practical and efficient tool to study the seismic response of a structure in interaction with the surrounding soil medium. Applications to a bridge pier show the potentialities of this kind of model.  相似文献   
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