Economic clusters have been a central focus of current urban and regional research, policies and practices. However, a methodology to identify and analyze policy-relevant economic cluster dynamics is still not well de...Economic clusters have been a central focus of current urban and regional research, policies and practices. However, a methodology to identify and analyze policy-relevant economic cluster dynamics is still not well developed. Based on input-output(I-O) data of 1987, 1992, 1997, 2002 and 2007 of Beijing, this article presents an adapted principle component analysis for identifying the evolution of local economic cluster patterns. This research addresses the changes of economic interaction of industries with complementary and common activities over time. The identified clusters provide an insight into the reality of economic development in a diversifying urban economy: the increasing importance of services and the growing interaction between service and manufacturing industries. Our method therefore provides the analysts with a better understanding of the emergence, disappearance and development of economic clusters citywide. The results could be used to assist monitoring urban economic development and designing more practical urban economic strategies.展开更多
In the knowledge economy era,science and technology(S&T) resources are getting more and more important in shaping regional competiveness and building regional innovation capacity.As such,the spatial distribution o...In the knowledge economy era,science and technology(S&T) resources are getting more and more important in shaping regional competiveness and building regional innovation capacity.As such,the spatial distribution of S&T resources is a key to understanding regional development and disparities.By designing an input-output indicator system,this paper develops an evaluation model to examine the spatial distribution of S&T resources in China and assess their spatial efficiency.Moreover,the paper tries to explain spatial differences in the efficiency of S&T resources in China.Major findings are:1) the input and output of S&T resources in China shows a clear T-shaped spatial structure,i.e.,concentrated mainly in the coastal region and along the Changjiang(Yangtze) River;2) the efficiency of S&T resources in China displays strong spatial disparities,with the level of efficiency descending from the east to the west while high efficiency appearing in only several clusters;3) the utilization rates of S&T resources in most provinces are quite low,resulting in low efficiency of S&T resources allocation.The paper suggests that the utilization rate of S&T resources should be raised and the commercialization of S&T outputs should be enhanced to improve the efficiency of S&T resources in China.展开更多
This letter presents a programmable single-chip architecture for Multi-lnput and Multi-Output (M1MO) OFDM baseband receiver. The architecture comprises a Single Instruction Multiple Data (SIMD) DSP core and three ...This letter presents a programmable single-chip architecture for Multi-lnput and Multi-Output (M1MO) OFDM baseband receiver. The architecture comprises a Single Instruction Multiple Data (SIMD) DSP core and three coprocessors that are used for synchronization, FFT and channel decoder. In this MIMO OFDM system, the Zero Correlation Zone (ZCZ) code is used as the synchronization word preamble of packet in the physical layer in order to avoid the interference from other transmitting antennas. Furthermore, a simple channel estimation algorithm is proposed which is appropriate tbr the SIMD DSP computation.展开更多
Under global production network,export cannot represent a country's gains from trade,and territory-based gains from trade refer to the remainder of export after deducting the input of intermediate goods and re-exp...Under global production network,export cannot represent a country's gains from trade,and territory-based gains from trade refer to the remainder of export after deducting the input of intermediate goods and re-export after value-added return.Ownership-based gains from trade refer to the remainder of territory-based gains from trade after further deducting the trade in value added(TVA) realized through the inflow of foreign factors.By creating a multicountry input and output model,this paper calculates the territory-based gains from trade,ownership-based gains from trade,and territory-based gains from trade for foreign countries realized through China's export,as well as valueadded return and territory-based gains from trade for foreign countries realized through China's import.This paper has arrived at the following conclusions:behind China's status as the largest goods exporting country in the world,most of Chinese exports contribute to the gains of foreign countries;value addition for foreign countries realized through China's export and value-added return realized through China's import mostly come from Taiwan region,Japan and South Korea in East Asia;a considerable part of gains from trade for the United States realized through China-US trade is achieved through indirect trade.展开更多
Wind power resources are abundant in China,especially in northern China and eastern coastal areas of China.Nevertheless,wind energy has intermittent and unstable characteristics,which leads to random power output and ...Wind power resources are abundant in China,especially in northern China and eastern coastal areas of China.Nevertheless,wind energy has intermittent and unstable characteristics,which leads to random power output and limits the large-scale utilization of wind energy resources.It has been shown that geographically dispersed wind plants have obvious spatiotemporal offsetting effect.Power output from each individual site exhibits the power ups and downs.However,when we simulate power lines connecting sites over a certain region,the output from them changes slowly and rarely reaches either very low or full power.Hence using the spatiotemporal complementarity of wind resources effectively is highly beneficial to the smoothing of power supply.This paper investigates the spatiotemporal complementarity of wind resources in China based on the relevant data of wind energy resources,which are offered by China Meteorological Administration(CMA).展开更多
The performance of a two-state quantum engine under different conditions is analyzed. It is shown that the efficiency of the quantum engine can be enhanced by superposing the eigenstates at the beginning of the cycle....The performance of a two-state quantum engine under different conditions is analyzed. It is shown that the efficiency of the quantum engine can be enhanced by superposing the eigenstates at the beginning of the cycle. By employing the finite-time movement of the potential wall, the power output of the quantum engine as well as the efficiency at the maximum power out- put (EMP) can be obtained. A generalized potential is adopted to describe a class of two-level quantum engines in a unified way. The results obtained show clearly that the performances of these engines depend on the external potential, the geometric configuration of the quantum engines, and the superposition effect. Moreow^r, it is found that the superposition effect will en- large the optimally operating region of quantum engines.展开更多
The estimation of regional input-output tables is well discussed in the literature and a large variety of methods exist. In this paper we will use the concept of fundamental economic structure (FES) to estimate the ...The estimation of regional input-output tables is well discussed in the literature and a large variety of methods exist. In this paper we will use the concept of fundamental economic structure (FES) to estimate the matrix of intermediate deliveries for some "missing" region(s). Furthermore, the estimates will be compared with the estimates obtained from "traditional" estimating techniques, including regionalization on the basis of the national table, and borrowing coefficients from similar regions. The results show FES is very helpful for compiling regional tables of China.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.41371008)
文摘Economic clusters have been a central focus of current urban and regional research, policies and practices. However, a methodology to identify and analyze policy-relevant economic cluster dynamics is still not well developed. Based on input-output(I-O) data of 1987, 1992, 1997, 2002 and 2007 of Beijing, this article presents an adapted principle component analysis for identifying the evolution of local economic cluster patterns. This research addresses the changes of economic interaction of industries with complementary and common activities over time. The identified clusters provide an insight into the reality of economic development in a diversifying urban economy: the increasing importance of services and the growing interaction between service and manufacturing industries. Our method therefore provides the analysts with a better understanding of the emergence, disappearance and development of economic clusters citywide. The results could be used to assist monitoring urban economic development and designing more practical urban economic strategies.
基金Under the auspices of National Science Fund for Distinguished Young Scholars(No.41125005)
文摘In the knowledge economy era,science and technology(S&T) resources are getting more and more important in shaping regional competiveness and building regional innovation capacity.As such,the spatial distribution of S&T resources is a key to understanding regional development and disparities.By designing an input-output indicator system,this paper develops an evaluation model to examine the spatial distribution of S&T resources in China and assess their spatial efficiency.Moreover,the paper tries to explain spatial differences in the efficiency of S&T resources in China.Major findings are:1) the input and output of S&T resources in China shows a clear T-shaped spatial structure,i.e.,concentrated mainly in the coastal region and along the Changjiang(Yangtze) River;2) the efficiency of S&T resources in China displays strong spatial disparities,with the level of efficiency descending from the east to the west while high efficiency appearing in only several clusters;3) the utilization rates of S&T resources in most provinces are quite low,resulting in low efficiency of S&T resources allocation.The paper suggests that the utilization rate of S&T resources should be raised and the commercialization of S&T outputs should be enhanced to improve the efficiency of S&T resources in China.
基金Supported by the National Natural Science Foundation of China (No.60476013).
文摘This letter presents a programmable single-chip architecture for Multi-lnput and Multi-Output (M1MO) OFDM baseband receiver. The architecture comprises a Single Instruction Multiple Data (SIMD) DSP core and three coprocessors that are used for synchronization, FFT and channel decoder. In this MIMO OFDM system, the Zero Correlation Zone (ZCZ) code is used as the synchronization word preamble of packet in the physical layer in order to avoid the interference from other transmitting antennas. Furthermore, a simple channel estimation algorithm is proposed which is appropriate tbr the SIMD DSP computation.
基金the outcome of major program of the National Social Sciences Foundation Research on the Upgraded Objectives and Strategic Innovation for the Transformation and Development of Major Trading Nations(Grant No.13&ZD048)
文摘Under global production network,export cannot represent a country's gains from trade,and territory-based gains from trade refer to the remainder of export after deducting the input of intermediate goods and re-export after value-added return.Ownership-based gains from trade refer to the remainder of territory-based gains from trade after further deducting the trade in value added(TVA) realized through the inflow of foreign factors.By creating a multicountry input and output model,this paper calculates the territory-based gains from trade,ownership-based gains from trade,and territory-based gains from trade for foreign countries realized through China's export,as well as valueadded return and territory-based gains from trade for foreign countries realized through China's import.This paper has arrived at the following conclusions:behind China's status as the largest goods exporting country in the world,most of Chinese exports contribute to the gains of foreign countries;value addition for foreign countries realized through China's export and value-added return realized through China's import mostly come from Taiwan region,Japan and South Korea in East Asia;a considerable part of gains from trade for the United States realized through China-US trade is achieved through indirect trade.
文摘Wind power resources are abundant in China,especially in northern China and eastern coastal areas of China.Nevertheless,wind energy has intermittent and unstable characteristics,which leads to random power output and limits the large-scale utilization of wind energy resources.It has been shown that geographically dispersed wind plants have obvious spatiotemporal offsetting effect.Power output from each individual site exhibits the power ups and downs.However,when we simulate power lines connecting sites over a certain region,the output from them changes slowly and rarely reaches either very low or full power.Hence using the spatiotemporal complementarity of wind resources effectively is highly beneficial to the smoothing of power supply.This paper investigates the spatiotemporal complementarity of wind resources in China based on the relevant data of wind energy resources,which are offered by China Meteorological Administration(CMA).
基金supported by the National Natural Science Foundation of China(Grant No.11005041)the Program for Prominent Young Talents in Fujian Province University(Grant No.JA12001)+2 种基金the Natural Science Foundation of Fujian Province(Grant Nos.2010J05007 and 2011J01012)the Fundamental Research Funds for the Central Universities(Grant No.JB-SJ1005)the Science Research Fund of Huaqiao University(Grant No.09BS510)
文摘The performance of a two-state quantum engine under different conditions is analyzed. It is shown that the efficiency of the quantum engine can be enhanced by superposing the eigenstates at the beginning of the cycle. By employing the finite-time movement of the potential wall, the power output of the quantum engine as well as the efficiency at the maximum power out- put (EMP) can be obtained. A generalized potential is adopted to describe a class of two-level quantum engines in a unified way. The results obtained show clearly that the performances of these engines depend on the external potential, the geometric configuration of the quantum engines, and the superposition effect. Moreow^r, it is found that the superposition effect will en- large the optimally operating region of quantum engines.
文摘The estimation of regional input-output tables is well discussed in the literature and a large variety of methods exist. In this paper we will use the concept of fundamental economic structure (FES) to estimate the matrix of intermediate deliveries for some "missing" region(s). Furthermore, the estimates will be compared with the estimates obtained from "traditional" estimating techniques, including regionalization on the basis of the national table, and borrowing coefficients from similar regions. The results show FES is very helpful for compiling regional tables of China.