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61.
本文为了解决物联网所连接对象的多样性带来的标识体系存在不兼容、相互矛盾的问题,基于车联网RFID汽车电子标识的使用特点,创造性地提出将OID编码和汽车电子标识编码相结合的方案。首先简单介绍了基于发证机构及时间和基于汽车VIN码的两种OID编码规则;然后提出了OID编码在汽车电子标识芯片中的规划,主要是内存分配方案;最后介绍了相应区域的读写操作的具体方法。 相似文献
62.
《Socio》2019
Human trafficking – the trade of persons for the gain of others – is a pervasive societal issue. Ongoing trafficking recruitment calls for targeted prevention strategies for individuals and communities at risk. Awareness campaigns, arguably the most common form of trafficking prevention, are intended to alert individuals to the tactics used by traffickers and provide them with practical strategies to avoid deception and exploitation. However there is a shortage of technical solutions regarding the analysis, impact assessment, and evaluation of alternatives related to implementing awareness campaigns. We present a resource allocation model that can be used to determine the allocation of funds that maximizes increases in trafficking awareness among at-risk populations. We apply this model to determine the allocation of a limited budget among different types of prevention programs in at-risk populations in Nepal. For each awareness campaign, we estimate a production function that relates the amount invested to the associated change in awareness. When allocating limited resources, decision makers must balance competing interests, and we illustrate the impact of three allocation policies on trafficking awareness. The model presented in this article is a first attempt to help decision makers evaluate how to allocate funds in the context of trafficking awareness. 相似文献
63.
针对电力公司运维物资多级库存体系与安全库存配置现状,结合安全库存聚集效应,文章提出了周转库安全库存差异聚集策略。在综合考虑库存持有成本与普通、紧急配送成本的基础上,构建了安全库存优化配置模型。通过两类电网运维物资实际数据的分析,验证了差异聚集策略下成本低于全部聚集以及全部分散策略,可以为电力公司物资集约化、差异化、精益化管理以及仓库定额配置提供依据。 相似文献
64.
Gilles Zumbach 《Quantitative Finance》2019,19(7):1097-1120
Despite being based on sound principles, the original Markovitz portfolio allocation theory cannot produce sound allocations, and restrictions or modifications need to be imposed from outside the theory in order to obtain meaningful portfolios. This is unsatisfactory, and the reasons for this failure are discussed, in particular, the unavoidable small eigenvalues of the covariance. Within the original principles of risk minimization and return maximization, several modifications of the original theory are introduced. First, the strategic and tactical time horizons are separated. A base long-term allocation is chosen at the strategic time horizon, while the portfolio is optimized at the tactical time horizon using information from the price histories. Second, the tactical portfolio is financed by the strategic one, and a funding operator is introduced. The corresponding optimal allocation (without constraints) has one free parameter fixing the leverage. Third, the transaction costs are taken into account. This includes the current re-allocation cost, but crucially the expected costs of the next reallocation. This last term depends on the sensitivity of the allocation with respect to the covariance, and the expectation introduces another dependency on the (inverse) covariance. The new term regularizes the original minimization problem by modifying the lower part of the spectrum of the covariance, leading to meaningful portfolios. Without constraints, the final Lagrangian can be minimized analytically, with a solution that has a structure similar to the original Markovitz solution, but with the inverse covariance regularized by the expected transaction costs. 相似文献
65.
As the retail industry is growing larger and more diversified, retailers' decisions about product selection, shelf-space-allocation, and replenishment become more important and challenging. This paper is to present a model for shelf-space allocation with product selection and replenishment decisions to maximize the retailer's profit. The model is based on a two-dimensional display space in which all shelves and products have widths and heights and includes factors that influence demand for each product, such as space and cross-space elasticities and positioning effects. The integrated model presented is mixed-integer non-linear programming (MINLP) because the demand function is non-convex. This research proposes two heuristic algorithms (tabu search and genetic) to solve the MINLP problem. The results show the effectiveness and efficiency of these algorithms by comparing the outputs to the MINLP optimal solution for small data sets and comparing the algorithm performances for large data sets. The solution methodologies expect to support a simultaneous decision-making process for retailers to maximize their revenue. 相似文献
66.
Land resources do not flow directly but can be allocated as “embodied land” in goods and services during economic globalization. The term “embodied arable land” can help link local land allocation strategies to the global and national supply chains and trade activities, and suggest new lens in optimizing arable land allocation. China is facing a serious arable land shortage, especially in municipal administrative areas. Based on the nested input-output analysis (Nested IOA), this work takes Shanghai as an example, exploring the allocation of direct and embodied arable land of an urban economy within the process of economic globalization. The amount of embodied arable land associated with Shanghai economy is 6.09 Mha, broken down into local arable land use (0.20 Mha), domestic inflows (3.20 Mha) and foreign inflows (2.69 Mha). This area supports local final demand (4.32 Mha), domestic outflows (1.24 Mha) and foreign outflows (0.53 Mha). Land-related imbalances emerge in the study, namely the economy’s demand versus the city’s size, the arable land demand versus supply, and embodied arable land inflows versus outflows. Regarding the role of the urban economy in allocation of global arable land under economic globalization, on the one hand, Shanghai has intensively involved with a large amount of embodied foreign arable land resources, and has been heavy dependent on foreign embodied arable land; On the other hand, there is still large potential for Shanghai to take the opportunity of economic globalization for an optimal allocation of direct and embodied arable land. Policy suggestions on taking the opportunity of economic globalization for an optimal allocation of direct and embodied arable land are put forward. 相似文献
67.
We study the house allocation problem with existing tenants: houses (stand for “indivisible objects”) are to be allocated to agents; each agent needs exactly one house and has strict preferences; houses are initially unowned; agents initially do not own houses; the remaining agents (the so-called “existing tenants”) initially own the remaining houses (each owns one). In this setting, we consider various randomized allocation rules under which voluntary participation of existing tenants is assured and the randomization procedure either treats agents equally or discriminates against some (or all) of the existing tenants. We obtain two equivalence results, which generalize the equivalence results in Abdulkadiroğlu and Sönmez (1999) and Sönmez and Ünver (2005). 相似文献
68.
How does news about future economic fundamentals affect within-country and cross-country credit allocation? How effective is unconventional policy when financial crises are driven by unfulfilled favorable news? I study these questions by employing a two-sector, two-country macroeconomic model with a banking sector in which financial crises are associated with occasionally binding leverage constraints. In response to positive news on the valuation of non-traded sector capital which turns out to be incorrect at a later date, the model captures the patterns of financial flows and current account dynamics in Spain between 2000–2010, including the changes in the sectoral allocation of bank credit and movements in cross-country borrowing during the boom and the bust. When there are unconventional policies by a common authority in response to unfulfilled favorable news, liquidity injections perform better in ameliorating the downturn than direct assets purchases from the non-traded sector. 相似文献
69.
《Socio》2015
We propose a network flow model for dynamic selection of temporary distribution facilities and allocation of resources for emergency response planning. The model analyzes the transfer of excess resources between temporary facilities operating in different time periods in order to reduce deprivation. Numerical analysis shows that the location of temporary facilities is determined by the demand and supply points. This work contributes to the emergency response planning that requires a quick response for the supply of relief materials immediately after a disaster hits a particular area. 相似文献
70.