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31.
German public transport services by bus are characterized by a regulatory framework that distinguishes between commercial and non-commercial services. Contrary to the apparent views of legislators, this paper shows that costs and revenues are not the only parameters determining whether or not operators are able to provide services in a commercially viable way.Apart from the local characteristics of the specific service, we show that the classification of services as commercial versus non-commercial is determined in large part by the public transport authorities that set minimum quality standards to be provided by operators. Our analysis shows that the authorities awarding the contracts in some cases affect market organization significantly depending on how they make use of this power. Furthermore, market organization differs substantially with respect to the awarding structure and the contractual relationships, thus creating a challenge for operators and authorities in an embryonic market.  相似文献   
32.
基于纺织科技文摘管理的现状,开发了纺织科技文摘管理系统。该系统包括数据的录入、维护、查询、统计等功能,采用纺织科技工作者和生产技术管理人员非常熟悉的“纺织工序”进行检索,使检索更加方便、直观,检索到的内容更为齐全。  相似文献   
33.
Future 5G networks aim at providing new high-quality wireless services to meet stringent and case-specific needs of various vertical sectors beyond traditional mobile broadband offerings. 5G is expected to disrupt the mobile communication business ecosystem and open the market to drastically new sharing based network operational models. 5G technical features of network slicing and small cell deployments in higher carrier frequencies will lower the investment barrier for new entrants to deploy local radio access networks and offer vertical specific services in specific areas and allow them lease the remaining required infrastructure on demand from mobile network operators (MNO) or infrastructure vendors. To realize the full vision of 5G to benefit the society and promote competition, innovation and emergence of new services when the 5G end-to-end network spans across different stakeholders administrative domains, the existing regulations governing the mobile communication business ecosystem are being refined. This paper provides a tutorial overview on how 5G innovations impact mobile communications and reviews the regulatory elements relevant to 5G development for locally deployed networks. This paper expands the recent micro licensing model for local spectrum authorization in future 5G systems and provides guidelines for the development of the key micro licensing elements. This local micro licensing model can open the mobile market by allowing different stakeholders to deploy local small cell networks with locally issued spectrum licenses ensuring pre-defined quality guarantees for the vertical sectors’ case specific needs.  相似文献   
34.
We study a stochastic model of influence where agents have “yes” or “no” inclinations on some issue, and opinions may change due to mutual influence among the agents. Each agent independently aggregates the opinions of the other agents and possibly herself. We study influence processes modeled by ordered weighted averaging operators, which are anonymous: they only depend on how many agents share an opinion. For instance, this allows to study situations where the influence process is based on majorities, which are not covered by the classical approach of weighted averaging aggregation. We find a necessary and sufficient condition for convergence to consensus and characterize outcomes where the society ends up polarized. Our results can also be used to understand more general situations, where ordered weighted averages are only used to some extent. Furthermore, we apply our results to fuzzy linguistic quantifiers, i.e., expressions like “most” or “at least a few”.  相似文献   
35.
为了帮助沥青路面再生工厂获得更好的经济与环境效益,提出一种基于改进遗传算法的布局优化方法。首先,确定再生工厂布局的约束条件,并以非物流相关性最大、物料搬运成本最低和碳排放最少作为优化目标建立工厂布局优化模型;其次,基于初始布局方案,采用实数分层编码及排列组合方法对各功能区的初始位置进行交叉互换,并根据约束条件进行筛选,得到合适的初始种群;再次,针对横坐标层与纵坐标层进行算数交叉,变异时坐标层采用多点变异,放置方式层采用单点变异,并引入模拟退火算子;最后,以某再生工厂为例对改进算法进行验证。结果表明:改进后的遗传算法迭代次数较传统遗传算法减少34次,目标函数值较文献中遗传算法减小0.009 9,提高了算法的寻优能力;优化后的方案每日物料搬运成本减少14 468.85元,碳排放减少30.59 kg,验证了方法的有效性。研究中所提出的优化方法效率较高,可为沥青路面再生工厂的建设提供技术支持。  相似文献   
36.
王琴  伍达富  赵钦 《科技和产业》2023,23(10):115-120
乡村民宿的发展既是乡村振兴的产业基础,也是促进少数民族文化复兴的有效方式,同时也增添了乡村的个性和特色。黔南州拥有秀丽的山水自然资源和独特的民族文化内涵,这对促进乡村民宿旅游发展具有显著优势,也为这种新型旅游模式提供了内生动能。运用实地调研和问卷调查方式,剖析了黔南州乡村民宿发展存在的问题,并针对性提出了加快黔南州乡村民宿发展的具体对策,以期促进黔南州乡村民宿健康稳定发展。  相似文献   
37.
Data envelopment analysis (DEA) has recently become relatively popular with road safety experts. Therefore, various decision-making units (DMUs), such as EU countries, have been assessed in terms of road safety performance (RSP). However, the DEA has been criticized because it evaluates DMUs based only on the concept of self-assessment, and, therefore does not provide a unique ranking for DMUs. Therefore, cross efficiency method (CEM) was developed to overcome this shortcoming. Peer-evaluations in addition to self-evaluation have made the CEM to be recognized as an effective method for ranking DMUs. The traditional CEM is based only on the standard CCR (Charnes, Cooper and Rhodes) model, and it evaluates DMUs according to their position relative to the best practice frontier while neglecting the worst practice frontier. However, the DMUs can also be assessed based on their position relative to the worst practice frontier. In this regard, the present study aims to provide a double-frontier CEM for assessing RSP by taking into account the best and worst frontiers simultaneously. For this purpose, the cross efficiency and cross anti-efficiency matrices are generated.Even though a weighted average method (WAM) is most frequently used for cross efficiency aggregation, the decision maker's (DM) preference structure may not be reflected. For this reason, the present study mainly focuses on the evidential reasoning approach (ERA), as a nonlinear aggregation method, rather than the linear WAM. Equal weights are often used for cross efficiency aggregation; consequently, the effect of the DM's subjective judgments in obtaining the overall efficiency is ignored. In this respect, the minimax entropy approach (MEA) and the maximum disparity approach (MMDA) are applied for determining the ordered weighted averaging (OWA) operator weights for cross efficiency aggregation. The weighted cross efficiencies and cross anti-efficiencies are then aggregated using the ERA. Finally, the proposed method, called DF-CEM-ERA, is used to evaluate the RSP of EU countries as well as Serbian police departments (PDs).  相似文献   
38.
目前,基于AHP法构建的供应商选择模型中,均未考虑实际决策时通常有多人参与,并且决策者会给出不同形式评价信息的情况。针对这一问题,将供应商选择视为一种不同形式偏好信息并存的群决策问题,结合AHP法,提出基于OWA算子的供应商选择模型。  相似文献   
39.
During the last three decades, integer‐valued autoregressive process of order p [or INAR(p)] based on different operators have been proposed as a natural, intuitive and maybe efficient model for integer‐valued time‐series data. However, this literature is surprisingly mute on the usefulness of the standard AR(p) process, which is otherwise meant for continuous‐valued time‐series data. In this paper, we attempt to explore the usefulness of the standard AR(p) model for obtaining coherent forecasting from integer‐valued time series. First, some advantages of this standard Box–Jenkins's type AR(p) process are discussed. We then carry out our some simulation experiments, which show the adequacy of the proposed method over the available alternatives. Our simulation results indicate that even when samples are generated from INAR(p) process, Box–Jenkins's model performs as good as the INAR(p) processes especially with respect to mean forecast. Two real data sets have been employed to study the expediency of the standard AR(p) model for integer‐valued time‐series data.  相似文献   
40.
从服务营销系统模型看电信服务竞争优势   总被引:1,自引:0,他引:1  
通信业务需求的飞速增长,直接导致异常激烈的电信业竞争。本质上,电信业竞争就是服务的竞争,正确把握这一理念是电信企业成功的关键因素之一。本文首先构造和分析了服务系统。其次,在此基础上分析其营销系统模型,并以中国移动通信公司(CMCC)所提供的服务,对相关问题做了进一步的分析与说明。最后,给出了电信运营企业如何获得服务竞争优势的几点建议。  相似文献   
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