Coal pillar design has historically assigned a factor of safety(Fo S) or stability factor(SF) according to their estimated strength and the assumed overburden load acting on them. Acceptable Fo S values have been assi...Coal pillar design has historically assigned a factor of safety(Fo S) or stability factor(SF) according to their estimated strength and the assumed overburden load acting on them. Acceptable Fo S values have been assigned based on past mining experience or a statistical link between Fo S and probability of failure(Po F). Pillar width-to-height(w/h) ratio has long been established as having a material influence on both pillar strength and its potential failure mode. However, there has been significant disagreement on using both factor of safety(Fo S) and w/h as part of pillar system stability criterion, as compared to using Fo S in isolation. This paper will argue that there are valid technical reasons to bring w/h ratio into system stability criteria(other than its influence on pillar strength), as it is related to the post-failure stiffness of the pillar, as measured in situ, and its interaction with overburden stiffness. When overburden stiffness is also brought into pillar system stability considerations, two issues emerge. The first is the width-todepth(W/D) ratio of the panel and whether it is sub-critical or super-critical from a surface subsidence perspective. The second relates to a re-evaluation of pillar Fo S based on whether the pillar is in an elastic or non-elastic(i.e., post-yield) state in its as-designed condition, as this is relevant to maintaining overburden stiffness at the highest possible level. The significance of the model is the potential to maximise both reserve recovery and mining efficiencies without any discernible increase in geotechnical risk, particularly in thick seams and higher depth of cover mining situations. At a time when mining economics are, at best, marginal, removing potentially unnecessary design conservatism is of interest to all mine operators and is an important topic for discussion amongst the geotechnical community.展开更多
In the past fifteen years, the attention of ship safety treatment as an objective rather than a constraint has started to sweep through the whole maritime industry. The risk-based ship design (RBD) methodology, advo...In the past fifteen years, the attention of ship safety treatment as an objective rather than a constraint has started to sweep through the whole maritime industry. The risk-based ship design (RBD) methodology, advocating systematic integration of risk assessment within the conventional design process has started to takeoff. Despite this wide recognition and increasing popularity, important factors that could potentially undermine the quality of the results come from both quantitative and qualitative aspects during the risk assessment process. This paper details a promising solution by developing a formalized methodology for risk assessment through effective storing and processing of historical data combined with data generated through first-principle approaches. This method should help to generate appropriate risk models in the selected platform (Bayesian networks) which can be employed for decision making at design stare.展开更多
This paper reviews the history and progress of research on active tectonics in China and overseas.By giving a brief introduction on the history of active tectonic research in China and other countries,the paper sums u...This paper reviews the history and progress of research on active tectonics in China and overseas.By giving a brief introduction on the history of active tectonic research in China and other countries,the paper sums up the process and development of quantitative investigation of active tectonics since the 1980s.The focus is on the main efforts and progress made in China on certain aspects of research,such as basic surveys and applied investigation of active tectonics,the study of theories related to regional active tectonics and their kinematics and geodynamics,surveys on coupling relations between deep and shallow structures,active fault surveys and prospecting and seismic hazard assessment in urban areas,as well as the efforts made using Quaternary geochronology.Furthermore,the paper looks back on Chinese quantitative investigation of active tectonics in China and sums up cognitions derived from studies on the determination of several basic and measurable parameters of active tectonics.These parameters include the length of fault and fault segmentation,coseismic slip and cumulative slip,fault slip rate,the sequence of paleoearthquake events and the time elapsed since the most recent event.At the same time,efforts and progress made in China on assessing the long-term seismic potential for active faults and evaluating the risk from potential active fault movement have been reviewed by summarizing research on developing theories,models,methods and the application of time-dependent seismic potential to probabilistic assessment,magnitude estimation for potential earthquakes on active faults,and the forecast of potential risk caused by active fault movement.Finally,in consideration of the realities and problems in the research of active tectonics in China,the authors put forward several suggestions for issues worthy of more attention for further investigation in the future.展开更多
It has been a period of time since the concept of scenario earthquake was proposed, but this concept has rarely been used in seismic safety evaluation in China since then. Meanwhile, because of the uncertainties of ma...It has been a period of time since the concept of scenario earthquake was proposed, but this concept has rarely been used in seismic safety evaluation in China since then. Meanwhile, because of the uncertainties of magnitudes-distances pairs, there is large arbitrariness while determining the envelope function of time histories in seismic hazard analysis. In this paper, we describe a method to control the envelope functions of the time histories by introducing the most-likely combinations of magnitude and distance of the scenario earthquakes based on a probabilistic method, revise the software of the ellipse model for seismic hazard analysis, and give a computation example.展开更多
Accreditation requirements for reference material producers (RMP) are systematica duced from the viewpoints of origination causes, development history, and domestic and international status in quo.
This paper discusses three issues, raised by Relevance Lost (Johnson & Kaplan, 1987), about historical evaluation of the development of management accounting. The first issue is when management accounting system wa...This paper discusses three issues, raised by Relevance Lost (Johnson & Kaplan, 1987), about historical evaluation of the development of management accounting. The first issue is when management accounting system was formed; the second is how to evaluate its development in subsequent decades; the third is how to evaluate the development of practice and research of management accounting in almost twenty years after Relevance Lost was published. The role of Relevance Lost in practice and theoretical research of management accounting is widely recognized, and the disagreement with it in this paper is in the specific area of the development history of management accounting. The authors of this paper believe that the development, through having its ups and downs over time, is generally speaking a continuous process, not separated by disconnected phases, leaping from one to another. Along with the progress in practice and research, researchers and practitioners are deepening their understanding about the theoretical foundation and practical development of management accounting. The history of development of management accounting is consistent with the process people gradually understand it.展开更多
Small WWTP (wastewater treatment plants) are frequently located, by necessity, in remote and isolated sites, which increases the difficulty of its energy supply. This paper describes a case study which is a step by ...Small WWTP (wastewater treatment plants) are frequently located, by necessity, in remote and isolated sites, which increases the difficulty of its energy supply. This paper describes a case study which is a step by step procedure concerning the evaluation of the wind potential of sites that are dependent of in-situ energy generation, as well as, on the utilization of the potential wind energy in Magoito WWTP. The adopted methodology comprised the collection of one year of in-situ wind data and its validation by comparison with historical data of more than 10 years of a nearby anemometric station. The data provided by the two anemometric stations was statistically treated and allowed the analysis of the results from the two stations. These results are promising in terms of wind availability and velocity. Finally, the study comprised the simulation of the local wind conditions for a considerable larger area in order to find the best site for locating a wind turbine.展开更多
Since the collapse of Euro-Communism in 1989, the ideas of Marx have largely been discarded as little more than historical relics. There is a good reason for the neglect. The governments that Marxism spawns are among ...Since the collapse of Euro-Communism in 1989, the ideas of Marx have largely been discarded as little more than historical relics. There is a good reason for the neglect. The governments that Marxism spawns are among the most brutal in history. Equally condemnable for a philosopher who bases his theory on a science of historical development, most of Marx's key predictions turn out to be incorrect. What then is left of Marx's principles? This paper argues that Marx is best understood as a critic of the injustice of industrial societies. Marx's essential critical concept is alienation. The paper presents the first complete analysis of Marx's treatment of alienation and offers a brief assessment of how this concept applies to our time.展开更多
This proposed project is not viable in profitable terms to private enterprise, so it applied a modified version of the CVM (Contingent Valuation Method) to realize this project. A survey was conducted in Lefkada Isl...This proposed project is not viable in profitable terms to private enterprise, so it applied a modified version of the CVM (Contingent Valuation Method) to realize this project. A survey was conducted in Lefkada Island in Greece, where 200 interviewees took part in order to consider whether they wish to voluntarily participate in the excavation and restoration of the ancient theater of Lefkada. Half of the interviewees were given information on the history of the site and then were asked to fill out a questionnaire. The other half of the interviewees were given no historical information on the archeological site and also were asked to fill out a questionnaire. The interviewees who were not given any information on the history of the site briefed on the history and then were asked to fill out another questionnaire. The purpose was to observe the different responses that the interviewees gave before and after being informed. This study aims to compare the WTP (Willingness To Participate) for this public good among those who were informed and those who were not.展开更多
文摘Coal pillar design has historically assigned a factor of safety(Fo S) or stability factor(SF) according to their estimated strength and the assumed overburden load acting on them. Acceptable Fo S values have been assigned based on past mining experience or a statistical link between Fo S and probability of failure(Po F). Pillar width-to-height(w/h) ratio has long been established as having a material influence on both pillar strength and its potential failure mode. However, there has been significant disagreement on using both factor of safety(Fo S) and w/h as part of pillar system stability criterion, as compared to using Fo S in isolation. This paper will argue that there are valid technical reasons to bring w/h ratio into system stability criteria(other than its influence on pillar strength), as it is related to the post-failure stiffness of the pillar, as measured in situ, and its interaction with overburden stiffness. When overburden stiffness is also brought into pillar system stability considerations, two issues emerge. The first is the width-todepth(W/D) ratio of the panel and whether it is sub-critical or super-critical from a surface subsidence perspective. The second relates to a re-evaluation of pillar Fo S based on whether the pillar is in an elastic or non-elastic(i.e., post-yield) state in its as-designed condition, as this is relevant to maintaining overburden stiffness at the highest possible level. The significance of the model is the potential to maximise both reserve recovery and mining efficiencies without any discernible increase in geotechnical risk, particularly in thick seams and higher depth of cover mining situations. At a time when mining economics are, at best, marginal, removing potentially unnecessary design conservatism is of interest to all mine operators and is an important topic for discussion amongst the geotechnical community.
基金the financial support received by the University of Strathclyde in the form of a postgraduate research scholarship for the duration of the second author’s P hD studies
文摘In the past fifteen years, the attention of ship safety treatment as an objective rather than a constraint has started to sweep through the whole maritime industry. The risk-based ship design (RBD) methodology, advocating systematic integration of risk assessment within the conventional design process has started to takeoff. Despite this wide recognition and increasing popularity, important factors that could potentially undermine the quality of the results come from both quantitative and qualitative aspects during the risk assessment process. This paper details a promising solution by developing a formalized methodology for risk assessment through effective storing and processing of historical data combined with data generated through first-principle approaches. This method should help to generate appropriate risk models in the selected platform (Bayesian networks) which can be employed for decision making at design stare.
基金funded by the"Experimental Exploration of Active Faults in Urban Areas(20041138)"project of the National Development and Reform Commission of China
文摘This paper reviews the history and progress of research on active tectonics in China and overseas.By giving a brief introduction on the history of active tectonic research in China and other countries,the paper sums up the process and development of quantitative investigation of active tectonics since the 1980s.The focus is on the main efforts and progress made in China on certain aspects of research,such as basic surveys and applied investigation of active tectonics,the study of theories related to regional active tectonics and their kinematics and geodynamics,surveys on coupling relations between deep and shallow structures,active fault surveys and prospecting and seismic hazard assessment in urban areas,as well as the efforts made using Quaternary geochronology.Furthermore,the paper looks back on Chinese quantitative investigation of active tectonics in China and sums up cognitions derived from studies on the determination of several basic and measurable parameters of active tectonics.These parameters include the length of fault and fault segmentation,coseismic slip and cumulative slip,fault slip rate,the sequence of paleoearthquake events and the time elapsed since the most recent event.At the same time,efforts and progress made in China on assessing the long-term seismic potential for active faults and evaluating the risk from potential active fault movement have been reviewed by summarizing research on developing theories,models,methods and the application of time-dependent seismic potential to probabilistic assessment,magnitude estimation for potential earthquakes on active faults,and the forecast of potential risk caused by active fault movement.Finally,in consideration of the realities and problems in the research of active tectonics in China,the authors put forward several suggestions for issues worthy of more attention for further investigation in the future.
基金sponsored under the keyresearch project of social development of Zhejiang Province(2005C23075)
文摘It has been a period of time since the concept of scenario earthquake was proposed, but this concept has rarely been used in seismic safety evaluation in China since then. Meanwhile, because of the uncertainties of magnitudes-distances pairs, there is large arbitrariness while determining the envelope function of time histories in seismic hazard analysis. In this paper, we describe a method to control the envelope functions of the time histories by introducing the most-likely combinations of magnitude and distance of the scenario earthquakes based on a probabilistic method, revise the software of the ellipse model for seismic hazard analysis, and give a computation example.
文摘Accreditation requirements for reference material producers (RMP) are systematica duced from the viewpoints of origination causes, development history, and domestic and international status in quo.
文摘This paper discusses three issues, raised by Relevance Lost (Johnson & Kaplan, 1987), about historical evaluation of the development of management accounting. The first issue is when management accounting system was formed; the second is how to evaluate its development in subsequent decades; the third is how to evaluate the development of practice and research of management accounting in almost twenty years after Relevance Lost was published. The role of Relevance Lost in practice and theoretical research of management accounting is widely recognized, and the disagreement with it in this paper is in the specific area of the development history of management accounting. The authors of this paper believe that the development, through having its ups and downs over time, is generally speaking a continuous process, not separated by disconnected phases, leaping from one to another. Along with the progress in practice and research, researchers and practitioners are deepening their understanding about the theoretical foundation and practical development of management accounting. The history of development of management accounting is consistent with the process people gradually understand it.
文摘Small WWTP (wastewater treatment plants) are frequently located, by necessity, in remote and isolated sites, which increases the difficulty of its energy supply. This paper describes a case study which is a step by step procedure concerning the evaluation of the wind potential of sites that are dependent of in-situ energy generation, as well as, on the utilization of the potential wind energy in Magoito WWTP. The adopted methodology comprised the collection of one year of in-situ wind data and its validation by comparison with historical data of more than 10 years of a nearby anemometric station. The data provided by the two anemometric stations was statistically treated and allowed the analysis of the results from the two stations. These results are promising in terms of wind availability and velocity. Finally, the study comprised the simulation of the local wind conditions for a considerable larger area in order to find the best site for locating a wind turbine.
文摘Since the collapse of Euro-Communism in 1989, the ideas of Marx have largely been discarded as little more than historical relics. There is a good reason for the neglect. The governments that Marxism spawns are among the most brutal in history. Equally condemnable for a philosopher who bases his theory on a science of historical development, most of Marx's key predictions turn out to be incorrect. What then is left of Marx's principles? This paper argues that Marx is best understood as a critic of the injustice of industrial societies. Marx's essential critical concept is alienation. The paper presents the first complete analysis of Marx's treatment of alienation and offers a brief assessment of how this concept applies to our time.
文摘This proposed project is not viable in profitable terms to private enterprise, so it applied a modified version of the CVM (Contingent Valuation Method) to realize this project. A survey was conducted in Lefkada Island in Greece, where 200 interviewees took part in order to consider whether they wish to voluntarily participate in the excavation and restoration of the ancient theater of Lefkada. Half of the interviewees were given information on the history of the site and then were asked to fill out a questionnaire. The other half of the interviewees were given no historical information on the archeological site and also were asked to fill out a questionnaire. The interviewees who were not given any information on the history of the site briefed on the history and then were asked to fill out another questionnaire. The purpose was to observe the different responses that the interviewees gave before and after being informed. This study aims to compare the WTP (Willingness To Participate) for this public good among those who were informed and those who were not.