This study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eige...This study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eigenfunction expansions. A complex dispersion relation is adopted to describe the wave elevation and energy dissipation over submerged porous bars. In the analytical solution, no limitations on the bar number, bar size, and spacing between adjacent bars are set. The convergence of the analytical solution is satisfactory, and the correctness of the analytical solution is confirmed by an independently developed multi-domain BEM （boundary element method） solution. Numerical examples are presented to examine the reflection and transmission coefficients of porous bars, CR and Cv, respectively, for engineering applications. The calculation results show that when the sum of widths for all the porous bars is fixed, increasing the bar number can significantly improve the sheltering function of the bars. Increasing the bar height can cause more wave energy dissipation and lower CR and Cr. The spacing between adjacent bars and the spacing between the last bar and the vertical wall are the key parameters affecting CR and Ct. The proposed analytical method may be used to analyze the hydrodynamic performance of submerged porous bars in preliminary engineering designs.展开更多
The revised new iterative method for solving the ground state of Schroedingerequation is deduced. Based on Green functions defined by quadratures along a single trajectory thisiterative method is applied to solve the ...The revised new iterative method for solving the ground state of Schroedingerequation is deduced. Based on Green functions defined by quadratures along a single trajectory thisiterative method is applied to solve the ground state of the double-well potential. The result iscompared to the one based on the original iterative method. The limitation of the asymptoticexpansion is also discussed.展开更多
According to the policy of reforming the power industry and accelerating the power construction of our country, by 2020, the national power consumption will be up to 3.6-3.7 trillion kilowatt-hours, the installed powe...According to the policy of reforming the power industry and accelerating the power construction of our country, by 2020, the national power consumption will be up to 3.6-3.7 trillion kilowatt-hours, the installed power-generating capacity is more than 800 million kilowatts. Therefore, the development of the China’s nuclear power industry faces good international and domestic environments and good historical opportunities. From the point of national energy security, economic development, and resource distribution, it is analyzed that China must develop the nuclear power in a more cost-effective style in this paper.展开更多
Afghanistan electricity sector has experienced many ups and downs of transitions from 1893 to date. With the growing global interest in Afghanistan rehabilitation, this paper presents an over view of Afghanistan elect...Afghanistan electricity sector has experienced many ups and downs of transitions from 1893 to date. With the growing global interest in Afghanistan rehabilitation, this paper presents an over view of Afghanistan electricity sector which includes the historical development trends, power generation potential, sustainable energy exploitation, electricity policy transition and immature policies experiences, and the legacy of the war. The lack of access to the basic information about Afghanistan power sector was one of the serious concerns of international donors and investors. Still, this information somehow has been kept in official documents wrap up. In this collection, the Afghanistan＇s electricity sector is pictured as a reference for Afghanistan electricity. It can be opening toward primary sources of Afghanistan electricity sector of the lessons learned and asset for researchers interesting in this topic.展开更多
The rapid change in economic growth and human civilization has led to a dramatic increase in energy utilization and electricity demand. That faces nations with the challenge of maintaining cost-effective and clean pow...The rapid change in economic growth and human civilization has led to a dramatic increase in energy utilization and electricity demand. That faces nations with the challenge of maintaining cost-effective and clean power energy production. This paper aims to present Afghanistan electricity sector development and energy resources exploitation in a broad context. With the global growing interest in Afghanistan rehabilitation, this paper presents energy development trends in Afghanistan. Besides, the future outlook up to 2032 and the challenges that face electricity sector are highlighted. This study tries to emerge the historical development, current status, and future direction of Afghanistan electricity sector till 2032, in a precise collection.展开更多
In recent years,China has made significant achievements in optimizing its energy structure and tapping into renewable energy.Wind power,in particular,has been doubled in its development year by year between 2005-2009....In recent years,China has made significant achievements in optimizing its energy structure and tapping into renewable energy.Wind power,in particular,has been doubled in its development year by year between 2005-2009.However,wind power develops too fast,which is not harmonious with the power system,the industry structure and the policy mechanism.Therefore,it is necessary to find the fundamental causes for the issue.Based on the inherent features and practical issues of wind power development in China,the role of wind power in energy development is put forward through probing logically into three perspectives,i.e.energy utilization,energy development and the ultimate objectives of wind power development.The current wind power development should be grounded on the improvement of wind power industrialization system,the smart grid and the research on new energy storage technology so as to lay firm foundations for large-scale development of wind power in the future.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51490675,51322903 and 51279224.)
文摘This study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eigenfunction expansions. A complex dispersion relation is adopted to describe the wave elevation and energy dissipation over submerged porous bars. In the analytical solution, no limitations on the bar number, bar size, and spacing between adjacent bars are set. The convergence of the analytical solution is satisfactory, and the correctness of the analytical solution is confirmed by an independently developed multi-domain BEM （boundary element method） solution. Numerical examples are presented to examine the reflection and transmission coefficients of porous bars, CR and Cv, respectively, for engineering applications. The calculation results show that when the sum of widths for all the porous bars is fixed, increasing the bar number can significantly improve the sheltering function of the bars. Increasing the bar height can cause more wave energy dissipation and lower CR and Cr. The spacing between adjacent bars and the spacing between the last bar and the vertical wall are the key parameters affecting CR and Ct. The proposed analytical method may be used to analyze the hydrodynamic performance of submerged porous bars in preliminary engineering designs.
文摘The revised new iterative method for solving the ground state of Schroedingerequation is deduced. Based on Green functions defined by quadratures along a single trajectory thisiterative method is applied to solve the ground state of the double-well potential. The result iscompared to the one based on the original iterative method. The limitation of the asymptoticexpansion is also discussed.
文摘According to the policy of reforming the power industry and accelerating the power construction of our country, by 2020, the national power consumption will be up to 3.6-3.7 trillion kilowatt-hours, the installed power-generating capacity is more than 800 million kilowatts. Therefore, the development of the China’s nuclear power industry faces good international and domestic environments and good historical opportunities. From the point of national energy security, economic development, and resource distribution, it is analyzed that China must develop the nuclear power in a more cost-effective style in this paper.
文摘Afghanistan electricity sector has experienced many ups and downs of transitions from 1893 to date. With the growing global interest in Afghanistan rehabilitation, this paper presents an over view of Afghanistan electricity sector which includes the historical development trends, power generation potential, sustainable energy exploitation, electricity policy transition and immature policies experiences, and the legacy of the war. The lack of access to the basic information about Afghanistan power sector was one of the serious concerns of international donors and investors. Still, this information somehow has been kept in official documents wrap up. In this collection, the Afghanistan＇s electricity sector is pictured as a reference for Afghanistan electricity. It can be opening toward primary sources of Afghanistan electricity sector of the lessons learned and asset for researchers interesting in this topic.
文摘The rapid change in economic growth and human civilization has led to a dramatic increase in energy utilization and electricity demand. That faces nations with the challenge of maintaining cost-effective and clean power energy production. This paper aims to present Afghanistan electricity sector development and energy resources exploitation in a broad context. With the global growing interest in Afghanistan rehabilitation, this paper presents energy development trends in Afghanistan. Besides, the future outlook up to 2032 and the challenges that face electricity sector are highlighted. This study tries to emerge the historical development, current status, and future direction of Afghanistan electricity sector till 2032, in a precise collection.
文摘In recent years,China has made significant achievements in optimizing its energy structure and tapping into renewable energy.Wind power,in particular,has been doubled in its development year by year between 2005-2009.However,wind power develops too fast,which is not harmonious with the power system,the industry structure and the policy mechanism.Therefore,it is necessary to find the fundamental causes for the issue.Based on the inherent features and practical issues of wind power development in China,the role of wind power in energy development is put forward through probing logically into three perspectives,i.e.energy utilization,energy development and the ultimate objectives of wind power development.The current wind power development should be grounded on the improvement of wind power industrialization system,the smart grid and the research on new energy storage technology so as to lay firm foundations for large-scale development of wind power in the future.
