Based on the conclusions of domestic and foreign research, we have analyzed the collapse-fall characteristics of overlying strata and the mechanism of aquifer-protective mining in shallow coal seam working faces at th...Based on the conclusions of domestic and foreign research, we have analyzed the collapse-fall characteristics of overlying strata and the mechanism of aquifer-protective mining in shallow coal seam working faces at the Shendong Mine. We have selected the height of the water-conducting fracture zone in overlying strata as a composite index and established the applicable conditions of aquifer-protective mining in shallow coal seams with a multi-factor synthetic-index classification method. From our calculations and analyses of variance, we used factors such as the overlying strata strength, mining disturbing factors and rock integrity as related factors of the composite index. We have classified the applicable conditions of aquifer-protective mining in shallow coal seams into seven types by comparing the result of the height of water-conducting fractured zones of long-wall and short-wall working faces with the thickness of the bedrock, the thickness of the weathered zone and the size of safety coal-rock pillars. As a result, we propose the preliminary classification system of aquifer-protective mining in shallow coal seams. It can provide a theoretical guidance for safe applications of aquifer-protective mining technology in shallow coal seams under similar conditions.展开更多
This works examine the responses of housing prices to the monetary policies in various Chinese cities. Thirty-five large and medium sized Chinese cities are classified into six clusters applying the minimum variance c...This works examine the responses of housing prices to the monetary policies in various Chinese cities. Thirty-five large and medium sized Chinese cities are classified into six clusters applying the minimum variance clustering method according to the calculated correlation coefficients between the housing price indices of every two cities.Time difference correlation analysis is then employed to quantify the relations between the housing price indices of the six clusters and the monetary policies.It is suggested that the housing prices of various cities evolved at different paces and their responses to the monetary policies are heterogeneous,and local economic features are more important than geographic distances in determining the housing price trends.展开更多
This study examines risk reporting in annual reports of Malaysian listed companies. The mandatory and voluntary disclosures of risk information are analyzed and the authors examine whether a relationship exists betwee...This study examines risk reporting in annual reports of Malaysian listed companies. The mandatory and voluntary disclosures of risk information are analyzed and the authors examine whether a relationship exists between company size, leverage, and industry type and risk disclosure levels. 150 listed companies from five industries are selected as sample. Content analysis and risk disclosure index of dichotomous measurement are used in data collection. Overall the results indicate that level of risk information disclosed in the annual reports is still minimal. OLS (Ordinary least squares) regression analysis indicates that the level of risk information disclosure is positively associated with size and not with leverage. However, a mixed result has been found for industry type; where only property industry shows a significant relationship with level of risk disclosure, and not for the other industries. This study contributes to financial reporting literature in relation to risk reporting, particularly the practice of Malaysian companies. Findings from this study are also useful to regulators and accounting standard setting body to assess the level of compliance to regulations and standards relating to risk reporting by these companies. More studies are required to further understand the importance of risk information disclosure, such as risk disclosure within specific industry, cross-country studies and usefulness of risk information disclosure from the stakeholders' perspectives.展开更多
基金Financial support for this work, provided by the research fund of the North China Institute of Science and Technology (No.A09002)the National Natural Science Foundation of China (No.50834005)the National Basic Research Program of China (No.2007CB209402)
文摘Based on the conclusions of domestic and foreign research, we have analyzed the collapse-fall characteristics of overlying strata and the mechanism of aquifer-protective mining in shallow coal seam working faces at the Shendong Mine. We have selected the height of the water-conducting fracture zone in overlying strata as a composite index and established the applicable conditions of aquifer-protective mining in shallow coal seams with a multi-factor synthetic-index classification method. From our calculations and analyses of variance, we used factors such as the overlying strata strength, mining disturbing factors and rock integrity as related factors of the composite index. We have classified the applicable conditions of aquifer-protective mining in shallow coal seams into seven types by comparing the result of the height of water-conducting fractured zones of long-wall and short-wall working faces with the thickness of the bedrock, the thickness of the weathered zone and the size of safety coal-rock pillars. As a result, we propose the preliminary classification system of aquifer-protective mining in shallow coal seams. It can provide a theoretical guidance for safe applications of aquifer-protective mining technology in shallow coal seams under similar conditions.
基金Supported by the Hundred Talent Program of the Chinese Academy of Sciences,the National Natural Science Foundation of China under Grant Nos.71103179 and 71102129Program for Young Innovative Research Team in China University of Political Science and Law, 2010 Fund Project under the Ministry of Education of China for Youth Who are Devoted to Humanities and Social Sciences Research 10YJC630425
文摘This works examine the responses of housing prices to the monetary policies in various Chinese cities. Thirty-five large and medium sized Chinese cities are classified into six clusters applying the minimum variance clustering method according to the calculated correlation coefficients between the housing price indices of every two cities.Time difference correlation analysis is then employed to quantify the relations between the housing price indices of the six clusters and the monetary policies.It is suggested that the housing prices of various cities evolved at different paces and their responses to the monetary policies are heterogeneous,and local economic features are more important than geographic distances in determining the housing price trends.
文摘This study examines risk reporting in annual reports of Malaysian listed companies. The mandatory and voluntary disclosures of risk information are analyzed and the authors examine whether a relationship exists between company size, leverage, and industry type and risk disclosure levels. 150 listed companies from five industries are selected as sample. Content analysis and risk disclosure index of dichotomous measurement are used in data collection. Overall the results indicate that level of risk information disclosed in the annual reports is still minimal. OLS (Ordinary least squares) regression analysis indicates that the level of risk information disclosure is positively associated with size and not with leverage. However, a mixed result has been found for industry type; where only property industry shows a significant relationship with level of risk disclosure, and not for the other industries. This study contributes to financial reporting literature in relation to risk reporting, particularly the practice of Malaysian companies. Findings from this study are also useful to regulators and accounting standard setting body to assess the level of compliance to regulations and standards relating to risk reporting by these companies. More studies are required to further understand the importance of risk information disclosure, such as risk disclosure within specific industry, cross-country studies and usefulness of risk information disclosure from the stakeholders' perspectives.