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排序方式: 共有15条查询结果,搜索用时 125 毫秒
1.
Investment decisions in the wireless industry applying real options   总被引:1,自引:0,他引:1  
The wireless industry is one of the most capital intensive high-technology industries. This paper applies real options techniques to estimate investments under uncertainty in two new ventures: (a) deferral of the expansion from 2.5G to 3G networks; and (b) expansion of a 2.5G network using Wi-Fi as an alternative technology. The cases are examined and analyzed both qualitatively and quantitatively, using realistic assumptions and parameters. Investment cost, number of subscribers, pricing of services, and risk are at the core of investment decision processing. In both cases, sensitivity analysis of the value of the (real) option considering the above key parameters was conducted, to extrapolate useful findings that should be taken into consideration by the decision makers in wireless companies.  相似文献   
2.
This paper analyzes the impact of WLAN technologies for incumbent MNOs based on an empirical cross-country study of the players in the public WLAN-hotspot market using the theory of disruptive innovation and theoretical extensions for the industry- and country-level. The main research question to be analyzed is whether and why PWLAN has shown a disruptive or sustaining impact trend for incumbent MNOs in the hotspot markets of Germany, the UK, and the USA in recent years. The results imply that incumbent MNOs and new entrants have taken advantage of the opportunity provided by PWLAN, but the market success of both types of players varies between the countries analyzed. Incumbent MNOs dominate in Germany but not in the UK and the USA. The reasons for these country-specific differences were further investigated, and the results suggest that the analysis of disruptive potential in telecommunications needs to include country- and firm-specific factors, which are, again, largely influenced by the local regulation.  相似文献   
3.
In recent years, significant attention has been directed toward the fifth generation of wireless broadband connectivity known as ‘5G’, currently being deployed by Mobile Network Operators. Surprisingly, there has been considerably less attention paid to ‘Wi-Fi 6’, the new IEEE 802.1ax standard in the family of Wireless Local Area Network technologies with features targeting private, edge-networks. This paper revisits the suitability of cellular and Wi-Fi in delivering high-speed wireless Internet connectivity. Both technologies aspire to deliver significantly enhanced performance, enabling each to deliver much faster wireless broadband connectivity, and provide further support for the Internet of Things and Machine-to-Machine communications, positioning the two technologies as technical substitutes in many usage scenarios. We conclude that both are likely to play important roles in the future, and simultaneously serve as competitors and complements. We anticipate that 5G will remain the preferred technology for wide-area coverage, while Wi-Fi 6 will remain the preferred technology for indoor use, thanks to its much lower deployment costs. However, the traditional boundaries that differentiated earlier generations of cellular and Wi-Fi are blurring. Proponents of one technology may argue for the benefits of their chosen technology displacing the other, requesting regulatory policies that would serve to tilt the marketplace in their favour. We believe such efforts need to be resisted, and that both technologies have important roles to play in the marketplace, based on the needs of heterogeneous use cases. Both technologies should contribute to achieving the goal of providing affordable, reliable, and ubiquitously available high-capacity wireless broadband connectivity.  相似文献   
4.
本文介绍了局域网Internet出口智能负载均衡系统的实现方法以及强大的优势,在未来的企业信息化的建设中,负载均衡技术将会发挥更大的作用。  相似文献   
5.
The paper focuses on third generation wireless technologies and on alternative technologies for wireless local area networks. The authors present the evolutionary migration path from second to third generation systems. Technological, economic and behavioral factors related to decision-making towards the migration are proposed. As an example, the paper studies the case of the national incumbent operator of India. It analyzes qualitatively the migration problem from the perspective of the operator, the equipment manufacturer and the users. For the quantitative analysis, real options are used to value the investment decisions. The analysis suggests that the initial (sunk) investment cost, the average revenue per user, the growth of the subscriber base and the volatility of the markets are the key factors in the investment process.  相似文献   
6.
《价值工程》2013,(8):187-188
Wi-Fi是一种可以将个人电脑、手持设备(如PDA、手机)等终端以无线方式相互连接的技术。Wi-Fi是一个无线网络通信技术的品牌,由Wi-Fi联盟(WiFi Alliance)所持有。目的是改善基于IEEE802.11标准的无线网络产品之间的互通性。使Wi-Fi设备无需接入传统家庭、办公室或热点网络,即可实现相互连接。  相似文献   
7.
为了降低网络密集部署对超高吞吐率(VHT) Wi-Fi性能的影响,提出了VHT Wi-Fi基于软件定义网络(SDN)的网络架构、无线网络侧虚拟化和增强型认证与快速切换技术,以提高系统的共存性、抗干扰性和安全性。实验结果表明,VHT Wi-Fi与SDN、网络功能虚拟化、伽罗瓦/计数模式协议结合,吞吐率性能获得约10%的提升,在保证安全性同时平均切换时延降低至40 ms,可保障VHT Wi-Fi在密集部署网络中发挥重要作用。  相似文献   
8.
The users' movements in the indoor environments differ based on the condition of the environments. During an indoor emergency, an efficient evacuation is required to help the users to move to the safe areas. Many types of incidents could impact the movements of users and this requires studying the behavior of the people during the evacuation. The reaction of the users to the incidents could affect the evacuation procedures and that could lead to several types of injuries or death. Each user understands and perceives the indoor environment differently and this plays a critical role in the evacuation. Furthermore, the users of the indoor environments have different rights to access the indoor spaces, which affects the movements of the users during an incident. This paper aims to support the evacuation of a building (educational building) in a crisis by using the integrated model of LADM-IndoorGML and the representation of the 3D model of the building. This research is presenting the initial assessment based on real world application. To reflect evacuation cases, we extended the conceptual model of LADM-IndoorGML to define the access rights for users of indoor environments during crisis. An evacuation exercise has been held at the Faculty of Applied Science at TU Delft to study the access rights during an incident. During the evacuation, Wi-Fi data has been collected for the users of the building for further analysis. A 3D model has been built for the Faculty of Applied Science to analyze the movement of the users. The collected data of the Wi-Fi access points have been structured and imported into the freeware database PostgreSQL/PostGIS. Furthermore, the geometry of 3D model was used to visualize the users’ movements as individuals and groups of users according to their connection to Wi-Fi access. Appropriate visualization has been created using QGIS. This paper demonstrates the entire process of analysis and visualization of users’ movements based on the Wi-Fi logs by using the extended LADM-IndoorGML. The outcome of the research has showed that the results for individual users and group users attached to the same access point differs. The study has also exhibited the importance of the time resolution on Monitoring the movements of a single user or group of users. The completed study clearly demonstrates that with the proposed extension, the integrated LADM-IndoorGML model is able to support the decision-making process during an incident in educational building.  相似文献   
9.
《Telecommunications Policy》2014,38(8-9):838-850
Wi-Fi congestion is a very real and growing problem.” So said then-Chairman of the FCC Genachowski in a recent proceeding, and this sentiment is widely heard. However, we are aware of very few engineering studies that have a bearing on this matter, and their conclusions are equivocal. Beyond this, evidence for “congestion problems” in the 2.4 GHz ISM band is anecdotal at best.While some users no doubt sometimes have service difficulties they ascribe to congestion, that is not sufficient to prove that there is a policy problem. In order to provide a basis for policy decisions, we offer an analysis of congestion metrics and results in the engineering literature. We conclude that there is little consensus on how to measure congestion, and that network metrics are difficult to correlate with user experience.We therefore propose a list of user experience-oriented service impairment criteria that, if met, would demonstrate that congestion exists to a degree that justifies regulatory intervention: For more than one of the key scenarios that are supported by an operator or technology there is a significant increase in the percentage of users who cannot complete a valuable task on a persistent, ubiquitous basis in spite of the use of state-of-the-art engineering/deployment best practices, and users׳ willingness to pay the market rate for the best available service level.Based on our assessment of public reports and experimental data, we conclude that there is currently no evidence for pervasive Wi-Fi congestion. We do not claim that the absence of evidence of congestion amounts to evidence for the absence of congestion. However, we do question the argument that congestion occurring somewhere, sometimes is a justification for regulatory intervention.  相似文献   
10.
This paper explores an approach to evaluating spatial service and layout efficiency of municipal Wi-Fi facilities for cyber infrastructure planning in the construction of a smart city. Based on the equilibrium principle that Wi-Fi services supply should meet the spatial demand for recreation, urgency, and security, two evaluation models were built. In the first model, the spatial service efficiency of Wi-Fi facilities is measured by a mean ratio of three types of demand spaces covered by Wi-Fi service. In the other model, spatial layout efficiency of each Wi-Fi facility is calculated by a demand load indicator - the sum of the three types of demand space's ratios of served quantity to the average quantity it should carry, and then assessed by relationship with its adjacent facilities. Corresponding statistical methods and analysis processes were also designed using the function modules found in ArcGIS software. The approach was applied to Wuhan city in 2016. After overlaying influence areas of 688 Wi-Fi facilities with demand spaces of 137 access points for recreation, 1200.99 km roads for urgency, 121.54 km2 regions for security, the results show that there exists a spatial disequilibrium between supply and demand of Wi-Fi service in Wuhan due to lack of comprehensive planning. Specifically, there are 67 points, 700.76 km roads, and 42.59 km2 regions of demand spaces covered by Wi-Fi service, with service efficiencies of 48.91%, 58.35%, and 35.04% respectively and an overall spatial service efficiency of 47.43%. Among all the Wi-Fi facilities, there are 481 carrying saturated demand, 3 straying from the centre of demand space, and 204 redundant. The overall spatial layout efficiency of Wi-Fi facilities is 43.01%. The conclusion is that the dense and massive redundant Wi-Fi facilities should be optimized, especially in the centre areas along the confluence of Yangtze and Han rivers and new Wi-Fi facilities supplemented in other ill-equipped areas. Since many metropolitan cities experience the same problem, this novel approach will find wide application in the future and offer improved evaluation strategies for researchers and policymakers.  相似文献   
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