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1.
One of the fastest growing technologies of our times is that of mobile phones. In this article we use the assumption that the diffusion of mobile technology, as measured by the number of active mobile accounts, follows the well known S-curve of natural growth in competition systems. The accuracy of the logistic fit is tested against actual data for the whole world, Europe, China and the GSM system. Using the produced models predictions concerning the future of mobile business are deliberated.According to these models active mobile accounts around the globe are expected to grow from 1.7 billion in 2004 to approximately 2 billion in 2008, reaching a peak penetration of 29.2%. Growth barriers, apart from the age of the potential user, are also low income and extreme poverty. Europe, early adopter of mobile technology and leader in active mobile accounts against all other regions in the world, has apparently reached a peak with almost every European, apart from the very young or very old, using a mobile phone. The mobile market in China is anticipated to exceed 500 million active accounts and may increase even further depending on the economic and social reform that is currently under way in that part of the world. GSM will most likely remain the leading mobile technology in the future as it is today.The growth process for the world, Europe, and the GSM system is almost completed and during this stage instabilities may occur before the potential emergence of a new wave of growth.  相似文献   

2.
Mobile service has been totally revolutionizing the service industry with the explosive growth in mobile application (‘app’) services. With the rapid proliferation of mobile app service, there is still a constant need for the research focusing on the precise and scientific prediction of the diffusion of mobile app service with consideration of competitive relationships. However, most of the relevant research dealing with diffusion did not consider the competition effect among mobile app services. In addition, in mobile app services, big competitors, which have a larger marketing share in same category, can interrupt the diffusion of other mobile app services significantly. Thus, the level of competitiveness also should be considered for more precise prediction of mobile app service. Accordingly, the present study proposes a new approach to analyse the degree of competitiveness of mobile app service categories using Herfindahl–Hirschman index and classify mobile app service categories. Then, this study systematically analyses their respective diffusion patterns based on the given empirical data using competitive Bass model. A case of Korean mobile service industry is presented to illustrate the proposed approach.  相似文献   

3.
第四方物流供应商选择的AHP-GRAP组合分析模型   总被引:2,自引:0,他引:2  
本文针对第四方物流供应商选择时存在的信息不完全现象,引入AHP和GRAP相结合的评价模型进行优化选择研究.该模型在采用AHP确定权重的基础上,充分利用了信息的灰色特性.通过算例分析,该方法较好地解决了选择和评估过程中所遇到的信息不完全、评价指标较多、部分指标之间存在相关或重复等复杂多因素综合决策问题.  相似文献   

4.
This paper analyzes WiBro, one of the emerging wireless technologies for portable Internet services (PIS), which are designed to enable mobile broadband access. Based on an empirical examination of consumer preferences for mobile broadband technologies and an estimation of the future demand for WiBro, this study proposes that WiBro should fill the gaps between competing mobile broadband technologies, such as 3G and WLAN.  相似文献   

5.
We attempted to estimate the economic value of environmental services provided by restored instream flows in the water-scarce Yaqui River Delta in Mexico. The Yaqui River begins near the U.S.-Mexico border and continues for 400 km before reaching the Oviachic dam, but has not reached the nearby Gulf of California for decades due to diversions for irrigation. These diversions have degraded the riparian ecosystem, coastal wetlands, and estuaries. Environmental services provided by restored flows in the Yaqui River would include healthy riverside vegetation, wetlands and estuaries, fish and wildlife habitats, non-use values, and recreation. A contingent valuation survey in 40 neighborhoods in the most populated Delta city, Ciudad Obregon, was administered to estimate non-market values of instream uses. Respondents were given a current and hypothetical Delta scenario (the latter assumed restored water flows in the River) and asked a willingness-to-pay (WTP) question regarding purchasing water for environmental flows through higher water bills. Results from 148 in-person interviews indicated that households would pay an average of 73 pesos monthly. WTP was found related to key variables suggested by economic theory and contingent valuation studies elsewhere: income, educational level, number of children in the household, and initial bid amount. These results will allow decision makers to compare the benefits generated by different water uses, including environmental services, and to manage scarce water resources under a long-term sustainable approach.  相似文献   

6.
The aim of this paper is to assess the possible contribution of an input-output model towards two of the basic principles of the sustainability strategy of integrated coastal zone management (ICZM) and Post-Normal Science. According to these principles, decision-support tools should offer a holistic perspective and handle high uncertainty. The difficulties in reaching sustainability are due partly to the prevailing use of “narrow-system-boundary” tools that are non-holistic. Consequently, they fail to capture important ecosystem services and ignore interdependencies between them. To comply with the basic principles, our method allows environmental assets to be evaluated in multiple units and integrates results from recent researches in natural sciences. Both enable coverage of interdependencies between ecosystem services. Thereby, we enlarge input-output modelling from the two conventional ecosystem services of sink and provisioning to the most vital ones: the supporting services. An application to the Seine estuary addresses the impacts of maritime transportation infrastructures on nursery habitats for commercial fish. The ecosystem services covered are life support and resource provisioning. Our results show that the restoration of a total of 73.7 km2 of nursery areas over the period 2004-2015 would result in a stock of sole in 2015 that exceeds the “business as usual” scenario by 44.2% (uncertainty range: 35.9%-69.9%). In spite of high restoration costs, the negative macro-economic impact is very low. However, on the sector level, a trade-off results between nurseries and three economic sectors. The quantification of such trade-offs in our model is particularly useful to public participation in decision-making.  相似文献   

7.
Studies that demonstrate the economic value of the ecosystem services provided by public conservation lands can contribute to a more accurate appraisal of the benefit of these lands. The objective of this study was to estimate the economic value, in real (2004) dollars, of the ecosystem services provided by the U.S. National Wildlife Refuge System (Refuge System) in the contiguous U.S. In order to estimate this value, we determined the ecosystems present on the Refuge System in the contiguous 48 states, the proportion in which they are represented, and the dollar value of services provided by each. We used land cover classes as an approximation of ecosystems present in the Refuge System. In a geographic information system (GIS), we combined land cover geospatial data with a map of the Refuge System boundaries to calculate the number of acres for each refuge and land cover class within the Refuge System. We transferred values for the following ecosystem services: climate and atmospheric gas regulation; disturbance prevention; freshwater regulation and supply; waste assimilation and nutrient regulation; and habitat provision. We conducted a central tendency value transfer by transferring averaged values taken from primarily original site studies to the Refuge System based on the ecoregion in which each study site and refuge was located and the ecoregion's relative net primary productivity (NPP). NPP is a parameter used to quantify the net carbon absorption rate by living plants, and has been shown to be correlated with spatially fungible ecosystem services. The methodologies used in the site studies included direct market valuation, indirect market valuation and contingent valuation. We estimated the total value of ecosystem services provided by the Refuge System in the contiguous U.S. to be approximately $26.9 billion/year. This estimate is a first cut attempt to demonstrate that the value of the Refuge System likely exceeds the value derived purely from recreational activities. Due to limitations of current understanding, methods and data, there is a potentially large margin of error associated with the estimate.  相似文献   

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