In current researches on spectrum leasing, Common model and Property-right model are two main approaches to dynamic spectrum sharing. However, Common model does not consider the obligation of Primary System (PS) and i...In current researches on spectrum leasing, Common model and Property-right model are two main approaches to dynamic spectrum sharing. However, Common model does not consider the obligation of Primary System (PS) and is unfair to Secondary System (SS), while the cooperation based on Property-rights model has problems on its feasibility. This paper proposes a novel system model, in which a Cost-Prediction scheme for Spectrum Leasing (CPSL scheme) is designed to forecast the cost that PS would pay for leasing spectrum. Cost Function is introduced as a criterion to evaluate the potential cost of spectrum leasing for PS. The simulation results show that compared with Common model based scheme, CPSL scheme substantially improves the QoS of the delay-sensitive traffic in SS at the cost of a small degradation of PS performance.展开更多
Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the dete...Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the detection of changing land use patterns in the Yanhe River Basin in northern Loess Plateau of China between 1995 and 2008. Landscape metrics were used to analyze the changing land use patterns and to explore the related anthropogenic driving forces. Results show that:1) Totally, 186 590 ha of croplands were converted into alternate land-use types (equivalent to 61.7% of the original cropland area). The majority of cropland areas were found to be converted into grassland and woodland areas (accounting for 55.9% and 4.9% respectively of the original cropland areas). 2) Both cropland and woodland demonstrated an increasing fragmentation tendency while grasslands showed a decreasing fragmentation tendency. 3) Multiple driving forces of land use change were thought to act together to changes in landscape metrics in the Yanhe River Basin. The anthropogenic driving forces were analyzed from four perspectives:ecological conservation policy, labor force transfer, industrial development, and rural settlement. The policy of the GfG (Grain for Green) project was the main driving factor which expedited the conversion from cropland to woodland and grassland. Industrial development was also found to affect land use change through the direct impact of economic activities such as oil exploration and agricultural production, or through indirect impacts such as the industrial structures readjustment. Labor force transfer from rural to urban areas was found to follow the industrial structure readjustment and further drove land use change from cropland to off-farm land use. Establishment of new tile-roofed houses instead of cave-type dwellings in rural settlements has helped to aggregate the original scattered land-use type of construction.展开更多
New digital trends are transforming the media industry landscape, modifying elemental characteristics and attitudes of companies as well as of consumers. Firms often claim that their presence in social media （SM） is...New digital trends are transforming the media industry landscape, modifying elemental characteristics and attitudes of companies as well as of consumers. Firms often claim that their presence in social media （SM） is a key element to success. SM helps companies rethink the traditional one-way flow of their marketing messages and to incorporate a new interactive pattern into their communications. Nevertheless, these tendencies involve problems of strategic myopia for firms that do not structurally integrate these tools. One main problem is that institutions can rarely differentiate between the various types of SM and the attributes thereof, while the literature equally reveals a number of contradictions in the subject. The present conceptual paper lays the foundations of a strategic approach to SM and discusses its theoretical implications. Following an overview on the concept of SM, through a content analysis of the specialized management literature （n = 14）, we present various best practices and reflect on the apparent lack of strategic thinking in using SM as a marketing application. Then, we compare these practical examples with general marketing strategy theory. By merging theory and practice, we aim to provide an insight towards a well-founded application of SM as a genuinely strategic marketing tool.展开更多
In conditions of high-tech industries, Information Technology （IT） is expected to help solve complex problems by expediting corporate operations and provide more efficient business processes. IT is one of the main f...In conditions of high-tech industries, Information Technology （IT） is expected to help solve complex problems by expediting corporate operations and provide more efficient business processes. IT is one of the main factors to improve business efficiency. The new technologies such as virtualisation, consolidation, cloud computing, and software-based solutions are great ways to minimise resource use while maximising the business value of information systems. Technologies and innovations are necessary to ride the inevitable tide of change. Most of enterprises are striving to reduce their computing costs through the means of virtualization. This demand of reducing the computing cost has led to the innovation of cloud computing. Cloud technology offers better computing through improved utilization and reduced administration and infrastructure costs. Cloud computing is the sum of Software as a Service （SaaS） and utility computing. Cloud computing represents a fundamental change in the way computing power is generated and distributed, transforming the delivery of IT tools and products into elastic, on demand services characterized by flexible ＂pay as you go＂ payment models. More than half of European Union （EU） businesses and consumers already use some kind of cloud services. The diffusion of cloud computing is expected to generate substantial direct and indirect impacts on economic and employment growth in the EU, thanks to the migration to a new IT paradigm enabling greater innovation and productivity. The cost of using digital technologies, such as information service providers, decreases as the number of users increases. All of these factors work together to promote a rapid growth in the demand for, and supply of, IT products and services.展开更多
Traditional logistics takes economic interest as the final goal. The frequency and changes of logistics activities have brought severe negative effects to the environment. At present, logistics industry has become the...Traditional logistics takes economic interest as the final goal. The frequency and changes of logistics activities have brought severe negative effects to the environment. At present, logistics industry has become the dominant industry in the third industries, and it is also the main driver for economic development. As more emphasis has been attached to the philosophy of sustainable development, low carbon emission and environmental protection, environmental logistics has become the trend of logistics management. In this paper, basic theories of logistics, development economics etc. are employed, the dialectical relationship between environmental logistics and sustainable development are analyzed through statistics, and proposals are put forward to develop environmental logistics.展开更多
With the rapid growth of the offshore wind industry, the innovative floating offshore wind turbine is chosen as the most feasible device to harvest the vast wind energy in deep water area. However there is no practica...With the rapid growth of the offshore wind industry, the innovative floating offshore wind turbine is chosen as the most feasible device to harvest the vast wind energy in deep water area. However there is no practical design guide for the floating wind turbine especially the floating foundation. In this paper, based on the investigation on the worldwide floating wind turbine and current available expertise on floating platforms accumulated in offshore O/G （oil and gas） industry, an integrated design methodology is presented according to the specialized characteristics of wind turbine, including the type selection of foundation and mooring system, design standard, design procedure, design conditions, key technologies involved. Finally a semi-submersible floating foundation is designed to support certain megawatt-rating wind turbine of Goldwind and also performance analysis and code checks are performed to validate the design. The design method of the floating foundation provided in this paper is proved feasible and can be adopted in practical engineering design.展开更多
基金supported by the National High Technology Research and Development Program of China ('863' Program, No.2009AA01Z242)National Natural Science Foundation of China (60972080)
文摘In current researches on spectrum leasing, Common model and Property-right model are two main approaches to dynamic spectrum sharing. However, Common model does not consider the obligation of Primary System (PS) and is unfair to Secondary System (SS), while the cooperation based on Property-rights model has problems on its feasibility. This paper proposes a novel system model, in which a Cost-Prediction scheme for Spectrum Leasing (CPSL scheme) is designed to forecast the cost that PS would pay for leasing spectrum. Cost Function is introduced as a criterion to evaluate the potential cost of spectrum leasing for PS. The simulation results show that compared with Common model based scheme, CPSL scheme substantially improves the QoS of the delay-sensitive traffic in SS at the cost of a small degradation of PS performance.
基金Under the auspices of National Natural Science Foundation of China(No.40930528)State Forestry Administration of China(No.201004058)External Cooperation Program of Chinese Academy of Sciences(No.29GJHZ0948)
文摘Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the detection of changing land use patterns in the Yanhe River Basin in northern Loess Plateau of China between 1995 and 2008. Landscape metrics were used to analyze the changing land use patterns and to explore the related anthropogenic driving forces. Results show that:1) Totally, 186 590 ha of croplands were converted into alternate land-use types (equivalent to 61.7% of the original cropland area). The majority of cropland areas were found to be converted into grassland and woodland areas (accounting for 55.9% and 4.9% respectively of the original cropland areas). 2) Both cropland and woodland demonstrated an increasing fragmentation tendency while grasslands showed a decreasing fragmentation tendency. 3) Multiple driving forces of land use change were thought to act together to changes in landscape metrics in the Yanhe River Basin. The anthropogenic driving forces were analyzed from four perspectives:ecological conservation policy, labor force transfer, industrial development, and rural settlement. The policy of the GfG (Grain for Green) project was the main driving factor which expedited the conversion from cropland to woodland and grassland. Industrial development was also found to affect land use change through the direct impact of economic activities such as oil exploration and agricultural production, or through indirect impacts such as the industrial structures readjustment. Labor force transfer from rural to urban areas was found to follow the industrial structure readjustment and further drove land use change from cropland to off-farm land use. Establishment of new tile-roofed houses instead of cave-type dwellings in rural settlements has helped to aggregate the original scattered land-use type of construction.
文摘New digital trends are transforming the media industry landscape, modifying elemental characteristics and attitudes of companies as well as of consumers. Firms often claim that their presence in social media （SM） is a key element to success. SM helps companies rethink the traditional one-way flow of their marketing messages and to incorporate a new interactive pattern into their communications. Nevertheless, these tendencies involve problems of strategic myopia for firms that do not structurally integrate these tools. One main problem is that institutions can rarely differentiate between the various types of SM and the attributes thereof, while the literature equally reveals a number of contradictions in the subject. The present conceptual paper lays the foundations of a strategic approach to SM and discusses its theoretical implications. Following an overview on the concept of SM, through a content analysis of the specialized management literature （n = 14）, we present various best practices and reflect on the apparent lack of strategic thinking in using SM as a marketing application. Then, we compare these practical examples with general marketing strategy theory. By merging theory and practice, we aim to provide an insight towards a well-founded application of SM as a genuinely strategic marketing tool.
文摘In conditions of high-tech industries, Information Technology （IT） is expected to help solve complex problems by expediting corporate operations and provide more efficient business processes. IT is one of the main factors to improve business efficiency. The new technologies such as virtualisation, consolidation, cloud computing, and software-based solutions are great ways to minimise resource use while maximising the business value of information systems. Technologies and innovations are necessary to ride the inevitable tide of change. Most of enterprises are striving to reduce their computing costs through the means of virtualization. This demand of reducing the computing cost has led to the innovation of cloud computing. Cloud technology offers better computing through improved utilization and reduced administration and infrastructure costs. Cloud computing is the sum of Software as a Service （SaaS） and utility computing. Cloud computing represents a fundamental change in the way computing power is generated and distributed, transforming the delivery of IT tools and products into elastic, on demand services characterized by flexible ＂pay as you go＂ payment models. More than half of European Union （EU） businesses and consumers already use some kind of cloud services. The diffusion of cloud computing is expected to generate substantial direct and indirect impacts on economic and employment growth in the EU, thanks to the migration to a new IT paradigm enabling greater innovation and productivity. The cost of using digital technologies, such as information service providers, decreases as the number of users increases. All of these factors work together to promote a rapid growth in the demand for, and supply of, IT products and services.
基金the project "Study on Ecological Economy of Shandong Province" supported by Social Science Office of Shandong Province (Grant No. O5DJ11)
文摘Traditional logistics takes economic interest as the final goal. The frequency and changes of logistics activities have brought severe negative effects to the environment. At present, logistics industry has become the dominant industry in the third industries, and it is also the main driver for economic development. As more emphasis has been attached to the philosophy of sustainable development, low carbon emission and environmental protection, environmental logistics has become the trend of logistics management. In this paper, basic theories of logistics, development economics etc. are employed, the dialectical relationship between environmental logistics and sustainable development are analyzed through statistics, and proposals are put forward to develop environmental logistics.
文摘With the rapid growth of the offshore wind industry, the innovative floating offshore wind turbine is chosen as the most feasible device to harvest the vast wind energy in deep water area. However there is no practical design guide for the floating wind turbine especially the floating foundation. In this paper, based on the investigation on the worldwide floating wind turbine and current available expertise on floating platforms accumulated in offshore O/G （oil and gas） industry, an integrated design methodology is presented according to the specialized characteristics of wind turbine, including the type selection of foundation and mooring system, design standard, design procedure, design conditions, key technologies involved. Finally a semi-submersible floating foundation is designed to support certain megawatt-rating wind turbine of Goldwind and also performance analysis and code checks are performed to validate the design. The design method of the floating foundation provided in this paper is proved feasible and can be adopted in practical engineering design.
