针对声学边界元法中解的非唯一性和奇异积分问题,基于组合亥姆霍兹积分方程公式(combined helmholtz integral equation formulation,CHIEF)法思想,将常规边界元方程和等效源方程进行联立,并利用两者方程系数矩阵间的耦合等价关系,间接...针对声学边界元法中解的非唯一性和奇异积分问题,基于组合亥姆霍兹积分方程公式(combined helmholtz integral equation formulation,CHIEF)法思想,将常规边界元方程和等效源方程进行联立,并利用两者方程系数矩阵间的耦合等价关系,间接替换计算常规边界元法中的奇异系数矩阵,进而提出一种具有全频域唯一解、高计算精度和高稳定性的耦合CHIEF法。该方法将等效源方程作为补充方程,不仅解决了传统CHIEF法内点补充方程失效的问题,而且矩阵的间接替换计算避免了直接计算奇异积分,显著提高了计算效率和精度。通过声辐射和声散射的典型算例对比了所提方法、常规边界元法、常规Burton-Miller法和等效源法的计算效果。结果表明,所提方法不仅在全波数域内均能获得唯一解,且其计算精度和效率均优于常规边界元法和常规Burton-Miller方法,其系数矩阵条件数远低于等效源法。展开更多
The River Chief System (RCS) has evolved from local innovative practices to a national water governance strategy to address the current challenges in China’s water environmental management. In contrast to existing re...The River Chief System (RCS) has evolved from local innovative practices to a national water governance strategy to address the current challenges in China’s water environmental management. In contrast to existing research that focuses on the strengths, weaknesses, and improvements of RCS, this study uses literature study to reveal the dynamic evolution of RCS through three phases, with RCS spreading from developed coastal areas to central and western inland regions. RCS’s diffusion path involves vertical diffusion between central and local levels and horizontal diffusion among local governments. Moreover, RCS has also achieved conceptual spillover, gradually expanding into other governance domains, such as the Lake Chief System, the Field Chief System, the Forestry Chief System, and the integration of multiple chief roles. However, it is essential to scrutinize the phenomenon of applying similar governance mechanisms to different areas, as it may result in challenges such as overburdening local governments, insufficient public participation, oversimplification of differences in natural resource endowments, and limited applicability. This study also provides suggestions on how to address these challenges. The study contributes theoretical insights and policy implications, providing a foundation for practical policy innovation.展开更多
The study sought to assess the role and significance of chiefs in the traditional governance system of Cape Coast,Teshie and Kumasi communities in Ghana.This study employed the case study comparative approach.A total ...The study sought to assess the role and significance of chiefs in the traditional governance system of Cape Coast,Teshie and Kumasi communities in Ghana.This study employed the case study comparative approach.A total of 85 participants were selected for the study using the snowballing method of sampling.Data were collected using a four-point Likert scale questionnaire.Data analysis and presentation of results were done by using mean and standard deviation.The study revealed that chieftaincy as an institution is deeply rooted in the local communities.It further revealed that a chief is both the politico-military and religious head.It was recommended that there is the need for the modern state to go beyond just involving chiefs in only sod cutting ceremonies and other state functions to include them in the implementation of local development policies.Further to this,the roles and functions of traditional authorities and local government officials must be well-defined and agreed upon and the public must be made to understand this delineation of responsibilities brought by the government.展开更多
China’s Ministry of Commerce(MOFCOM)and the Ministry of Industry and Information Technology(MIIT)have designed a stress-test for China’s labor-intensive industries,
China＇s Xinhua News Agency calls it the ＂biggest government reshuffle in years＂ in what is seen as a dra matic continuation of the previous seven rounds of cabinet restructuring that began in 1982.
文摘针对声学边界元法中解的非唯一性和奇异积分问题,基于组合亥姆霍兹积分方程公式(combined helmholtz integral equation formulation,CHIEF)法思想,将常规边界元方程和等效源方程进行联立,并利用两者方程系数矩阵间的耦合等价关系,间接替换计算常规边界元法中的奇异系数矩阵,进而提出一种具有全频域唯一解、高计算精度和高稳定性的耦合CHIEF法。该方法将等效源方程作为补充方程,不仅解决了传统CHIEF法内点补充方程失效的问题,而且矩阵的间接替换计算避免了直接计算奇异积分,显著提高了计算效率和精度。通过声辐射和声散射的典型算例对比了所提方法、常规边界元法、常规Burton-Miller法和等效源法的计算效果。结果表明,所提方法不仅在全波数域内均能获得唯一解,且其计算精度和效率均优于常规边界元法和常规Burton-Miller方法,其系数矩阵条件数远低于等效源法。
文摘The River Chief System (RCS) has evolved from local innovative practices to a national water governance strategy to address the current challenges in China’s water environmental management. In contrast to existing research that focuses on the strengths, weaknesses, and improvements of RCS, this study uses literature study to reveal the dynamic evolution of RCS through three phases, with RCS spreading from developed coastal areas to central and western inland regions. RCS’s diffusion path involves vertical diffusion between central and local levels and horizontal diffusion among local governments. Moreover, RCS has also achieved conceptual spillover, gradually expanding into other governance domains, such as the Lake Chief System, the Field Chief System, the Forestry Chief System, and the integration of multiple chief roles. However, it is essential to scrutinize the phenomenon of applying similar governance mechanisms to different areas, as it may result in challenges such as overburdening local governments, insufficient public participation, oversimplification of differences in natural resource endowments, and limited applicability. This study also provides suggestions on how to address these challenges. The study contributes theoretical insights and policy implications, providing a foundation for practical policy innovation.
文摘The study sought to assess the role and significance of chiefs in the traditional governance system of Cape Coast,Teshie and Kumasi communities in Ghana.This study employed the case study comparative approach.A total of 85 participants were selected for the study using the snowballing method of sampling.Data were collected using a four-point Likert scale questionnaire.Data analysis and presentation of results were done by using mean and standard deviation.The study revealed that chieftaincy as an institution is deeply rooted in the local communities.It further revealed that a chief is both the politico-military and religious head.It was recommended that there is the need for the modern state to go beyond just involving chiefs in only sod cutting ceremonies and other state functions to include them in the implementation of local development policies.Further to this,the roles and functions of traditional authorities and local government officials must be well-defined and agreed upon and the public must be made to understand this delineation of responsibilities brought by the government.
文摘China’s Ministry of Commerce(MOFCOM)and the Ministry of Industry and Information Technology(MIIT)have designed a stress-test for China’s labor-intensive industries,
文摘China＇s Xinhua News Agency calls it the ＂biggest government reshuffle in years＂ in what is seen as a dra matic continuation of the previous seven rounds of cabinet restructuring that began in 1982.
