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991.
This article explores the phenomenon of ‘bikelash’, or organised community opposition to cycle lanes. Urban residents commonly cite bicycle lanes, a space on the road reserved for cyclists, as the infrastructure most likely to encourage them to cycle. Yet the introduction of cycle lanes is often controversial. This article explores the phenomenon of bikelash, asking: Why does it occur? And what are the best ways to respond to it? A critical review of the literature on ‘contested’ cycle lane projects is undertaken in order to explore how this phenomenon can best be conceptualised within a mobilities framework.  相似文献   
992.
In human mortality modelling, if a population consists of several subpopulations it can be desirable to model their mortality rates simultaneously while taking into account the heterogeneity among them. The mortality forecasting methods tend to result in divergent forecasts for subpopulations when independence is assumed. However, under closely related social, economic and biological backgrounds, mortality patterns of these subpopulations are expected to be non-divergent in the future. In this article, we propose a new method for coherent modelling and forecasting of mortality rates for multiple subpopulations, in the sense of nondivergent life expectancy among subpopulations. The mortality rates of subpopulations are treated as multilevel functional data and a weighted multilevel functional principal component (wMFPCA) approach is proposed to model and forecast them. The proposed model is applied to sex-specific data for nine developed countries, and the results show that, in terms of overall forecasting accuracy, the model outperforms the independent model and the Product-Ratio model as well as the unweighted multilevel functional principal component approach.  相似文献   
993.
Critical infrastructure systems must be both robust and resilient in order to ensure the functioning of society. To improve the performance of such systems, we often use risk and vulnerability analysis to find and address system weaknesses. A critical component of such analyses is the ability to accurately determine the negative consequences of various types of failures in the system. Numerous mathematical and simulation models exist that can be used to this end. However, there are relatively few studies comparing the implications of using different modeling approaches in the context of comprehensive risk analysis of critical infrastructures. In this article, we suggest a classification of these models, which span from simple topologically‐oriented models to advanced physical‐flow‐based models. Here, we focus on electric power systems and present a study aimed at understanding the tradeoffs between simplicity and fidelity in models used in the context of risk analysis. Specifically, the purpose of this article is to compare performance estimates achieved with a spectrum of approaches typically used for risk and vulnerability analysis of electric power systems and evaluate if more simplified topological measures can be combined using statistical methods to be used as a surrogate for physical flow models. The results of our work provide guidance as to appropriate models or combinations of models to use when analyzing large‐scale critical infrastructure systems, where simulation times quickly become insurmountable when using more advanced models, severely limiting the extent of analyses that can be performed.  相似文献   
994.
Cross-docking is a logistic strategy widely adopted both in manufacturing and distribution contexts. Despite the huge number of researches on this topic, most of them remain rather theoretical as they do not pay enough attention to operational aspects and daily functioning patterns of cross-dockings. This article aims at introducing a new focus for cross-docking research by proposing a visual planning solution to manage daily operation of a manufacturing cross-docking. By avoiding complex optimization algorithms and by adopting concepts belonging to the lean management theory, the article shows the potential of visual planning techniques to improve performance of cross-dockings. Starting from a specific industrial context, the shipping warehouse of an Italian company of the oil andand gas sector, a visual management methodology has been proposed to support the operation of cross-dockings. Although developed in a particular context, the proposed methodology and its underlying principles are to be considered general and potentially applicable to a wide range of cross-dockings. The methodology fully exploits an analytical tool, namely, the Safety Margin coefficientthat could be used for capacity planning purposes and to evaluate quantitatively the system performance at a given time instant.  相似文献   
995.
Integrating retail decisions on such aspects as assortment, pricing, and inventory greatly improves profitability. We examine a multi-period selling horizon where a retailer jointly optimizes assortment planning, pricing, and inventory decisions for a product line of substitutable products, in a market with multiple customer segments. Focusing on fast-moving retail products, the problem is modeled as a mixed-integer nonlinear program where demand is driven by exogenous consumer reservation prices and endogenous assortment and pricing decisions. A mixed-integer linear reformulation is developed, which enables an exact solution to large problem instances (with up to a hundred products) in manageable times. Empirical evidence is provided in support of a classical deterministic maximum-surplus consumer choice model. Computational results and managerial insights are discussed. We find that the optimal assortment and pricing decisions do not exhibit a simple, intuitive structure that could be analytically characterized, which reflects the usefulness of optimization approaches to numerically identify attractive trade-offs for the decision-maker. We also observe that suboptimal inventory policies significantly decrease profitability, which highlights the importance of integrated decision-making. Finally, we find that the seasonality of consumer preferences and supply costs present an opportunity for boosting the profit via higher inventory levels and wider assortments.  相似文献   
996.
Major accident risks posed by chemical hazards have raised major social concerns in today's China. Land‐use planning has been adopted by many countries as one of the essential elements for accident prevention. This article aims at proposing a method to assess major accident risks to support land‐use planning in the vicinity of chemical installations. This method is based on the definition of risk by the Accidental Risk Assessment Methodology for IndustrieS (ARAMIS) project and it is an expansion application of severity and vulnerability assessment tools. The severity and vulnerability indexes from the ARAMIS methodology are employed to assess both the severity and vulnerability levels, respectively. A risk matrix is devised to support risk ranking and compatibility checking. The method consists of four main steps and is presented in geographical information‐system‐based maps. As an illustration, the proposed method is applied in Dagushan Peninsula, China. The case study indicated that the method could not only aid risk regulations on existing land‐use planning, but also support future land‐use planning by offering alternatives or influencing the plans at the development stage, and thus further enhance the roles and influence of land‐use planning in the accident prevention activities in China.  相似文献   
997.
998.
张瀝元 《民族学刊》2021,12(4):80-88, 119
择医实践是指当一个人感到不适,为了证实是否有疾病和为了减少疾痛为目的寻求帮助的行为,是医学人类学研究主要课题之一。由于社会文化背景、地理条件等因素,藏族聚居地区医疗模式显现出多元共存,与之对应,当地民众的择医实践也呈现出一种多元状态。正是由于人们多元择医实践的诉求、固守与调适,才推进着多元医疗模式在发展中适应区域群体的文化变迁、需求改变而日趋完善,由此医疗模式与择医实践形成了互动、互构关系。  相似文献   
999.
In this article, we develop a series estimation method for unknown time-inhomogeneous functionals of Lévy processes involved in econometric time series models. To obtain an asymptotic distribution for the proposed estimators, we establish a general asymptotic theory for partial sums of bivariate functionals of time and nonstationary variables. These results show that the proposed estimators in different situations converge to quite different random variables. In addition, the rates of convergence depend on various factors rather than just the sample size. Finite sample simulations are provided to evaluate the finite sample performance of the proposed model and estimation method.  相似文献   
1000.
Prime aim is to examine the way the culture sector reuses industrial buildings to instigate cultural activities in the municipalities. The discussion of various actors’ motivation for engagement is based on results from a case study, supplemented with findings from a coarse-meshed telephone survey. At national level overarching political guidelines can be traced back to white papers concerning cultural policy, urban transformation and cultural heritage, and the municipalities’ cultural policies mirror these guidelines. What tends to decide if such initiatives are considered successful are local abilities to cross sectorial divisions and instigate cooperation between municipal planners, private entrepreneurs and NGOs.  相似文献   
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