Complex networks have been a prominent topic of research for several years,spanning a wide range of fields from mathematics to computer science and also to social and biological sciences.The eigenvalues of the Seidel ...Complex networks have been a prominent topic of research for several years,spanning a wide range of fields from mathematics to computer science and also to social and biological sciences.The eigenvalues of the Seidel matrix,Seidel Signless Laplacian matrix,Seidel energy,Seidel Signless Laplacian energy,Maximum and Minimum energy,Degree Sum energy and Distance Degree energy of the Unitary Cayley graphs[UCG]have been calculated.Low-power devices must be able to transfer data across long distances with low delay and reliability.To overcome this drawback a small-world network depending on the unitary Cayley graph is proposed to decrease the delay and increase the reliability and is also used to create and analyze network communication.Small-world networks based on the Cayley graph have a basic construction and are highly adaptable.The simulation result shows that the small-world network based on unitary Cayley graphs has a shorter delay and is more reliable.Furthermore,the maximum delay is lowered by 40%.展开更多
Observations show that Type Ia supernovae (SNe Ia) are dimmer than ex- pected from a matter dominated Universe. It has been suggested that this observed phenomenon can also be explained using light absorption instea...Observations show that Type Ia supernovae (SNe Ia) are dimmer than ex- pected from a matter dominated Universe. It has been suggested that this observed phenomenon can also be explained using light absorption instead of dark energy. However, there is a serious degeneracy between the cosmic absorption parameter and the present matter density parameter Ωm when one tries to place constraints on the cosmic opacity using SNe Ia data. We combine the latest baryon acoustic oscillation (BAO) and Union2 SNe Ia data in order to break this degeneracy. Assuming a fiat ACDM model, we find that, although an opaque Universe is favored by SNe Ia+BAO since the best fit value of the cosmic absorption parameter is larger than zero, fire = 1 is ruled out at the 99.7% confidence level. Thus, cosmic opacity is not sufficient to account for the present observations and dark energy or modified gravity is still re- quired.展开更多
Due to heavy energy consumption and low technical efficiency, China's iron and steel industry is trapped in the dilemma "large but not strong". This situation not only exerts enormous pressure on energy security bu...Due to heavy energy consumption and low technical efficiency, China's iron and steel industry is trapped in the dilemma "large but not strong". This situation not only exerts enormous pressure on energy security but also on increased carbon emission and environmental pollution. The contribution of this study is to calculate the energy and environment efficiency of China's iron and steel industry and to analyze the factors affecting this efficiency. An index of energy and environment efficiency is introduced based on Directional Slacks-based Distance Measure Model. This index is adopted to measure the energy and environment efficiency of China's iron and steel industry using 2,382 firm observations during 2001 to 2005. In addition, Hierarchy Linear Model (HLM) is applied to analyze the factors which can influence the efficiency with both firm-level and province-level data. The conclusions are as follows: The energy and environment efficiency of China's iron and steel industry did not have a significant change during the research period. A firm's age, size, ownership, product category and the economy of its province have significant influence on its energy and environment efficiency.展开更多
文摘Complex networks have been a prominent topic of research for several years,spanning a wide range of fields from mathematics to computer science and also to social and biological sciences.The eigenvalues of the Seidel matrix,Seidel Signless Laplacian matrix,Seidel energy,Seidel Signless Laplacian energy,Maximum and Minimum energy,Degree Sum energy and Distance Degree energy of the Unitary Cayley graphs[UCG]have been calculated.Low-power devices must be able to transfer data across long distances with low delay and reliability.To overcome this drawback a small-world network depending on the unitary Cayley graph is proposed to decrease the delay and increase the reliability and is also used to create and analyze network communication.Small-world networks based on the Cayley graph have a basic construction and are highly adaptable.The simulation result shows that the small-world network based on unitary Cayley graphs has a shorter delay and is more reliable.Furthermore,the maximum delay is lowered by 40%.
基金supported by the National Natural Science Foundation of China(Grant Nos. 10935013, 11175093, 11222545 and 11075083)Zhejiang Provincial Natural Science Foundation of China (Grant Nos. Z6100077 and R6110518)+6 种基金the Foundation for the Author of National Excellent Doctoral Dissertation of PR China (FANEDD, Grant No. 200922)the National Basic Research Program of China (973 program, Grant No. 2010CB832803)the Program for New Century Excellent Talents in University (NCET, Grant No. 09-0144)the Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT, Grant No. IRT0964)Hunan Provincial Natural Science Foundation of China (Grant No. 11JJ7001)the Specialized Research Fund for the Doctoral Program of Higher Education (SRFDP, Grant No. 20124306110001)the Program for the Key Discipline in Hunan Province
文摘Observations show that Type Ia supernovae (SNe Ia) are dimmer than ex- pected from a matter dominated Universe. It has been suggested that this observed phenomenon can also be explained using light absorption instead of dark energy. However, there is a serious degeneracy between the cosmic absorption parameter and the present matter density parameter Ωm when one tries to place constraints on the cosmic opacity using SNe Ia data. We combine the latest baryon acoustic oscillation (BAO) and Union2 SNe Ia data in order to break this degeneracy. Assuming a fiat ACDM model, we find that, although an opaque Universe is favored by SNe Ia+BAO since the best fit value of the cosmic absorption parameter is larger than zero, fire = 1 is ruled out at the 99.7% confidence level. Thus, cosmic opacity is not sufficient to account for the present observations and dark energy or modified gravity is still re- quired.
文摘Due to heavy energy consumption and low technical efficiency, China's iron and steel industry is trapped in the dilemma "large but not strong". This situation not only exerts enormous pressure on energy security but also on increased carbon emission and environmental pollution. The contribution of this study is to calculate the energy and environment efficiency of China's iron and steel industry and to analyze the factors affecting this efficiency. An index of energy and environment efficiency is introduced based on Directional Slacks-based Distance Measure Model. This index is adopted to measure the energy and environment efficiency of China's iron and steel industry using 2,382 firm observations during 2001 to 2005. In addition, Hierarchy Linear Model (HLM) is applied to analyze the factors which can influence the efficiency with both firm-level and province-level data. The conclusions are as follows: The energy and environment efficiency of China's iron and steel industry did not have a significant change during the research period. A firm's age, size, ownership, product category and the economy of its province have significant influence on its energy and environment efficiency.