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71.
移动商务身份认证机制的评价方法主要为安全性证明的形式化分析方法和单一指标比较的系统仿真方法,缺乏对认证机制性能的整体评价。移动商务身份认证评价体系必须满足移动商务身份认证的特点,即体现对移动商务特性及身份认证效果的检验。本文首先分析移动商务身份认证机制的应用现状和主要评价方法的不足,接着从安全性、适用性和成熟性设计移动商务身份认证评价体系的总体架构,最后逐层细化探讨了其各指标的选取。  相似文献   
72.
This paper analyzes the evolution of prices and competition in intra-EU international roaming markets. It addresses three main research questions: (i) to what extent have market forces by themselves brought competition to retail roaming markets? (ii) Has the evolution of market dynamics in wholesale roaming improved competition? (iii) Is wholesale regulation sufficient to lead to a reduction in retail roaming prices? Data show that there has been little price-based competition both at wholesale and retail levels, despite prices being well above costs and the significant margins allowed by regulation. Available data from the period preceding the entry into force of the first EU roaming regulation also point to the same conclusion. Lack of competitive pressure in retail roaming markets and inelastic demand give little incentives for retail roaming service providers to lower prices. Wholesale international roaming markets have complex competition dynamics. They are characterized by the reciprocity of wholesale roaming agreements and traffic internalization inside transnational groups. These circumstances limit price competition at the wholesale level. The traditional regulatory approach applied to electronic communication markets has been primarily focused on wholesale regulation. However, empirical evidence shows that even if wholesale charges are reduced, retail roaming markets continue to operate at very high retail margins (for example, more than 200% retail mark-up over wholesale charges for data roaming services and incoming calls). This proves that in international roaming markets wholesale charge reductions are not necessarily passed on to retail prices. It can thus be inferred that wholesale price regulation alone is in most cases not sufficient to ensure that benefits are passed through to end users.  相似文献   
73.
Over the past two decades, the mobile communications industry has seen a considerable drop in the consumer switching charges made by service providers in order to promote effective competition and ensure a level playing field for new market entrants. Mobile Number Portability (MNP) is an important regulatory measure taken to reduce switching costs, and it is believed to play an important role in fostering competition in the mobile market. MNP implementation has varied significantly across European Union countries, particularly with respect to porting time and customer fees, both of which are important factors when deciding whether to switch to another provider. The research examines the effects of MNP implementation on competition in the European mobile communications industry. The study findings indicate that subscriber churn rates are negatively affected by both the level of charges levied on subscribers wishing to maintain their current number (porting) when switching mobile providers and the length of time required to switch. The implications of the effectiveness of MNP regulation for competition in the mobile communications industry are discussed.  相似文献   
74.
This paper demonstrates how revealed- and stated-preference analyses can be used for modeling network effects in the field of mobile telecommunications. The aim of this study was to verify if network effects may still play a role in the Polish mobile telecommunications market, measure their strength, identify their sources and variability across consumers by accounting for consumers' observable and unobservable preference heterogeneity, evaluate their monetary value to consumers, and finally, to verify if the marginal utility associated with network effects is constant. The analysis of consumers' revealed choices (currently used mobile telephone operator) allowed the identification of major differences between customer bases of incumbent and new entrant operators, and insight into the business strategies adopted in the presence of asymmetric regulation of mobile termination rates. The second part of the study—the analysis of the consumers' stated choices (made in carefully prepared and designed hypothetical choice situations, known as the choice experiments) made it possible to directly model consumers' utility functions and, in this way, investigate the nature of network effects in mobile telecommunications markets. From the results, the presence of strong network effects, which are related to the ratio of consumers' social network group using the same operator, and to the magnitude of on-net price discounts, is confirmed. These network effects can be disaggregated to pecuniary and non-pecuniary effects. Through the utilization of the random parameters multinomial logit model, consumers' observable and unobservable preference heterogeneity can be accounted for, which proved a scientifically revealing and potentially policy-relevant approach. The results might be of a particular interest to other researchers aiming at modeling consumers' preferences as well as to mobile telephone operators and regulatory authorities—it is shown that capacity for vigorous price competition between mobile operators is limited by non-price factors, which affect subscriber's choices, especially in the presence of asymmetric mobile termination rates.  相似文献   
75.
Flat rates are a prominent pricing scheme for telecommunications services and are often preferred by consumers although average costs would be lower in an alternative usage-based tariff. Reasons are that flat rates protect against unexpectedly high costs (insurance effect), are more likely to be chosen if actual usage is overestimated (overestimation effect), and prevent any disutility that is associated with the immediate perception of marginal costs (taximeter effect). This study complements the literature on tariff biases by highlighting that a lack of tariff flexibility is a major impediment to choosing a flat rate: empirical support for this flexibility effect is found, while, at the same time, the insurance and overestimation effect that run in favor of flat rates are confirmed. Finally, the managerial implications of the findings for the introduction of the new cost cap tariff are discussed. The hybrid cost cap tariff can combine the flexibility and the insurance property, and may, therefore, exert a cost cap bias on consumers.  相似文献   
76.
为了实现多手段通信资源的全局共用与优化使用,针对通信节点多传输手段的自组网特点,提出了一种基于节点MPR的OLSR路由协议(N-OLSR)。首先对HELLO报文格式进行修改,加入Port字段,根据通信手段的不同,对Willingnes字段的值做出修改,用接口索引来代替接口IP地址,将链路带宽大的信道用大索引号表示。以此为基础,从全局出发制定路由策略,将通信节点作为MPR的选举对象,改变传统方法在每个接口上进行MPR选举的机制。最后,通过仿真实验来测试N-OLSR路由协议的性能。结果表明,改进的协议完成了MPR从接口到节点的转移,降低了源节点将一跳邻居节点选为MPR的频率,从而减少TC报文的产生以及洪泛;改进的路由协议能够减少控制开销,降低丢包率,加快网络收敛速度。研究结果可为多传输手段的移动自组网提供一种可靠的路由协议方案,并且信道带宽越小越能发挥其性能。  相似文献   
77.
ABSTRACT

The authors examine the use of mobile money in the context of cross-border remittances in West Africa. Relying on mixed methods and a multi-sited empirical strategy they look at both the sending and receiving conditions of mobile money transfers. By looking at money as socially embedded and the role of migrants in the production of a transnational space, their results highlight that uptake and usage of mobile money for remittances are shaped by a transnational living pattern. At the same time, mobile money also contributes to strengthening and reshaping this pattern. By showing that conversion of virtual money to cash may be performed by brokers that live far away from the end recipient, the paper highlights an important gap between spatial distribution of mobile money infrastructure and the social mediation that supports e-money flows. Cash-based transactions, in turn, are shown to play a key role in the social mediation dynamic.  相似文献   
78.
我国粮食仓储以平房仓为主,平房仓移动式输送及装仓设备使用量很大,操作过程中人机交叉点很多,人员及设备的安全性均存在着很大的安全隐患。基于此,阐述粮食平房仓移动式输送及装仓设备安全操作规程,以期对平房仓库安全作业有一定的指导和借鉴意义。  相似文献   
79.
The use of mobile devices by consumers and the accompanying response by retailers is rapidly revolutionizing the retail environment. In the past, retailers have focused primarily on the outcome (to purchase or not to purchase) of the consumer decision process, but now mobile technologies give retailers the opportunity to more actively influence the entire consumer decision-making processes. The increasing use of mobile devices by consumers makes shopping a continuous rather than discrete activity that requires retailers to engage with their customers at critical touch points of the decision process in order to provide a more customer-centric experience. This change in focus from the decision outcome to the decision process signifies an important paradigm shift for the retailing industry. After an extensive review of the literature, we identify four pillars that form the foundation for the mobile shopping revolution and represent the essential ways and means through which retailers can engage with consumers during the decision process. We also discuss the different areas in which the pillars can enable retailers to achieve a sustainable competitive advantage in the mobile shopping era.  相似文献   
80.
ABSTRACT

Mobile money is a mobile-phone-based financial tool that can transfer money safely and quickly across a wide geographical area. Mobile money has transformed the way businesses in Eastern sub-Saharan Africa operate. Nowadays, banks team up with mobile-money-service providers and pay interest on deposits and grant loans based on financial transactions in mobile-money accounts. In this paper, these recent developments are investigated in order to determine whether the adoption of mobile money by firms can actually help them mitigate the vexing problem of access to finance. To answer this question, the World Bank’s Enterprise Surveys Program data set for the year 2013 is used, thus making the study applicable to the present time. The results obtained, after controlling for a large number of firm-level characteristics and using a newly introduced measure to identify access-to-finance status of the firms, indicate that firms which use mobile money are more likely to obtain loans or lines of credit. Further analysis shows that the firms that use mobile money are more productive than other firms in the region.  相似文献   
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