The significance of this study lies in its exploration of the advanced applications of Geographic Information Systems (GIS) in assessing urban flood risks, with a specific focus on Midar, Morocco. This research is piv...The significance of this study lies in its exploration of the advanced applications of Geographic Information Systems (GIS) in assessing urban flood risks, with a specific focus on Midar, Morocco. This research is pivotal as it showcases that GIS technology is not just a tool for mapping, but a critical component in urban planning and emergency management strategies. By meticulously identifying and mapping flood-prone areas in Midar, the study provides invaluable insights into the potential vulnerabilities of urban landscapes to flooding. Moreover, this research demonstrates the practical utility of GIS in mitigating material losses, a significant concern in flood-prone urban areas. The proactive approach proposed in this study, centered around the use of GIS, aims to safeguard Midar’s population and infrastructure from the devastating impacts of floods. This approach serves as a model for other urban areas facing similar challenges, highlighting the indispensable role of GIS in disaster preparedness and response. Overall, the study underscores the transformative potential of GIS in enhancing urban resilience, making it a crucial tool in the fight against natural disasters like floods.展开更多
The Wenchuan Earthquake of May 12,2008 triggered large numbers of geo-hazards.The heavy rain on 13 August 2010 triggered debris flows with total volume of more than 6 million cubic meters and the debris flows destroye...The Wenchuan Earthquake of May 12,2008 triggered large numbers of geo-hazards.The heavy rain on 13 August 2010 triggered debris flows with total volume of more than 6 million cubic meters and the debris flows destroyed 500 houses and infrastructure built after the Wenchuan Earthquake.The study area Qingping Town was located in the northwestern part of the Sichuan Basin of China,which needs the second reconstructions and the critical evaluation of debris flow.This study takes basin as the study unit and defines collapse,landslide and debris flow hazard as a geo-hazard system.A multimode system composed of principal series system and secondary parallel system were established to evaluate the hazard grade of debris flow in 138 drainage basins of Qingping Town.The evaluation result shows that 30.43% of study basins(42 basins) and 24.58% of study area,are in extremely high or high hazard grades,and both percentage of basin quantity and percentage of area in different hazard grades decrease with the increase of hazard grade.According to the geo-hazard data from the interpretation of unmanned plane image with a 0.5-m resolution and field investigation after the Wenchuan Earthquake and 8.13 Big Debris Flow,the ratio of landslides and collapses increased after the Wenchuan Earthquake and the ratios of extremely high or high hazard grades were more than moderate or low hazard grades obviously.23 geo-hazards after8.13 Big Debris Flow in Qingping town region all occurred in basins with extremely high or high hazard grades,and 9 debris flows were in basins with extremely high hazard grade.The model of multimode system for critical evaluation could forecast not only the collapse and landslide but also the debris flow precisely when the basin was taken as the study unit.展开更多
Modern surface mines, either mono-system or multi-systems, need a large fleet of equipment consisting of excavators, loaders, haulers and auxiliary machines. Presently, the complexity of the system, the interference b...Modern surface mines, either mono-system or multi-systems, need a large fleet of equipment consisting of excavators, loaders, haulers and auxiliary machines. Presently, the complexity of the system, the interference between sub-systems and the lag in management skills has been a bottle neck for improving productivity of the system. Based on the fact that the traditional tools for safety analysis have been insufficient to evaluate systematically and dynamically the safety risks, this paper tries to create a virtual reality tool consisting of human, machine and mines, using Pro/E and the 3D MAX software in order to evaluate visually the operations of typical mining equipment, such as the bucket wheel excavator (BWE), the shovel, the truck and the dragline. Within this virtual world, the behavior of the system, such as interaction, interference and potential risk can be replayed and reviewed visually. The objective of the study is to identify the critical safety issues of the system and to provide a convenient and powerful tool for safety training and safety management.展开更多
Expert systems are methods that can cope with rock engineer’s expertise effectively.An expert system on assessing rockburst risks for South African deep gold mines is described.Expertise was represented by rules, fra...Expert systems are methods that can cope with rock engineer’s expertise effectively.An expert system on assessing rockburst risks for South African deep gold mines is described.Expertise was represented by rules, frames and mathematical models integratively. About 950 rules was built in the knowledge base, which can be learned by the suggested learning algorithm. A new uncertain reasoning algorithm was proposed. According to the features such as depth below surface, energy release rate (ERR), excess shear stress (ESS), geological structure, face angle with structure, distance from structure, extent of mining, mining type, width of bracket pillar, stope width, local support, regional support and gully support, rockburst risk is assessed either "Low", "Moderate", "High" or "Severe". A computer program system was developed by Turbo Prolog. The results of testing cases show its applicability of the system.展开更多
Flood control system risk evaluation is an effective measure for flood risk management and decisions.In order to make better flood risk decisions and thereby improve social and economic benefits,the flood control risk...Flood control system risk evaluation is an effective measure for flood risk management and decisions.In order to make better flood risk decisions and thereby improve social and economic benefits,the flood control risk evaluation index system should be built to quantify and normalize flood risk effectively and efficiently.Because the current evaluation index has the binary miscibility characteristic of fuzziness and clarity,this paper establishes a new flood control system risk evaluation method based on the theory of variable sets(VS).Through a comparison of flood control risk evaluation with variable fuzzy sets(VFS) in the same basin flood control system risk evaluation,it is revealed that the new method,i.e.,flood control risk evaluation with variable fuzzy/clear mixture sets(variable sets),will be reasonable in all cases.Finally,in one case study,i.e.,the flood control system risk evaluation of Fengman Reservoir Basin,which is located in the southeast central of Jilin Province in China,the risk evaluation levels for each county in the basin as well as the whole flood risk distribution map of the basin could be provided with the new method.This provides useful information for basin flood control planning and design.展开更多
Background: In patients with difuse large B?cell lymphoma(DLBCL), central nervous system(CNS) relapse is uncom?mon but is nearly always fatal. This study aimed to determine the risk factors for CNS relapse in DLBCL pa...Background: In patients with difuse large B?cell lymphoma(DLBCL), central nervous system(CNS) relapse is uncom?mon but is nearly always fatal. This study aimed to determine the risk factors for CNS relapse in DLBCL patients and to evaluate the eicacy of rituximab and intrathecal chemotherapy prophylaxis for CNS relapse reduction.Methods: A total of 511 patients with newly diagnosed DLBCL treated at the Sun Yat?sen University Cancer Center between January 2003 and December 2012 were included in the study. Among these patients, 376 received R?CHOP regimen(rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) as primary treatment, and 135 received CHOP regimen(cyclophosphamide, doxorubicin, vincristine, and prednisone) as primary treatment. Intrathe?cal chemotherapy prophylaxis(methotrexate plus cytarabine) was administered to those who were deemed at high risk for CNS relapse. In the entire cohort and in the R?CHOP set in particular, the Kaplan–Meier method coupled with the log?rank test was used for univariate analysis, and the Cox proportional hazards model was used for multivariate analysis. Diferences were evaluated using a two?tailed test, and P < 0.05 was considered signiicant.Results: At a median follow?up of 46 months, 25(4.9%) patients experienced CNS relapse. There was a trend of reduced occurrence of CNS relapse in patients treated with rituximab; the 3?year cumulative CNS relapse rates were 7.1% in CHOP group and 2.7% in R?CHOP group(P = 0.045). Intrathecal chemotherapy prophylaxis did not confer much beneit in terms of preventing CNS relapse. Bone involvement [hazard ratio(HR) = 4.21, 95% conidence interval(CI) 1.38–12.77], renal involvement(HR = 3.85, 95% CI 1.05–14.19), alkaline phosphatase(ALP) >110 U/L(HR = 3.59, 95% CI 1.25–10.34), serum albumin(ALB) <35 g/L(HR = 3.63, 95% CI 1.25–10.51), treatment with rituxi?mab(HR = 0.34, 95% CI 0.12–0.96), and a time to complete remission ≤ 108 days(HR = 0.22, 95% CI 0.06–0.78) were independent predictive factors for CNS relapse in the entire cohort. Bone involvement(HR = 4.44, 95% CI 1.08–18.35), bone marrow involvement(HR = 11.70, 95% CI 2.24–60.99), and renal involvement(HR = 10.83, 95% CI 2.27–51.65) were independent risk factors for CNS relapse in the R?CHOP set.Conclusions: In the present study, rituximab decreased the CNS relapse rate of DLBCL, whereas intrathecal chemo?therapy prophylaxis alone was not suicient for preventing CNS relapse. Serum levels of ALB and ALP, and the time to complete remission were new independent predictive factors for CNS relapse in the patients with DLBCL. In the patients received R?CHOP regimen, a trend of increased CNS relapse was found to be associated with extranodal lesions.展开更多
Currently,the global carbon trading systems are fragmented and belong to different governments or are under the jurisdiction of different regions,resulting in a series of new problems,such as how to link dispersed tra...Currently,the global carbon trading systems are fragmented and belong to different governments or are under the jurisdiction of different regions,resulting in a series of new problems,such as how to link dispersed trading systems,how to compare the emission reduction of various markets and other issues.Since the development of the international carbon market is relatively immature with uncertain life expectancy and volatility during its short history,and there is a lack of quantitative data on the long-term record,the market could provide few risk management tools.Meanwhile,with the launches of China's regional carbon trading pilots in seven provinces since 2013 and combined with the national voluntary emission trading system,carbon trading will become an important mechanism for China in achieving its emission reduction target.In the first stage,the carbon finance market is at least faced with mechanism design risks,market supply risks and compliance risks.Therefore,to secure the development of the carbon market and for public interest,relevant government departments of China should identify the risks facing the market and should make the basic principles and goals,such as ensuring effective trading and pricing mechanisms to avoid fraud and price manipulation,and balancing transparency and confidentiality of information.Consequently,the governments should develop a comprehensive carbon finance regulatory system covering regulatory legislation,regulatory institutions and their authorities,regulatory scope as well as regulatory objects.展开更多
Related to complexity, there is a wide diversity of concepts, ranging from ‘‘systemic" to ‘‘complex", implying a need for a unified terminology. Per different authors, the main drivers of complexity can ...Related to complexity, there is a wide diversity of concepts, ranging from ‘‘systemic" to ‘‘complex", implying a need for a unified terminology. Per different authors, the main drivers of complexity can be found in human behaviour and uncertainty. This complexity, structural or dynamic can be organizational, technological, or nested in their relationship. ISO international standard 31000:2009 definition of risk management ‘‘coordinated activities to direct and control an organization with regard to risk", when applied to economic sectors, industry, services, project, or activity, it requires the use of models or theories as guidelines. Therefore, as its basic elements comprehend human behaviour and/or uncertainty, risk management to be effective and adapted as much as possible to reality, must be operational within complex systems, as already demonstrated in different R&D environments. Risk management faces demanding challenges when approaching specific and endogenous needs, such as the mining sector. This paper presents a multivariable function analysis methodology approach based on complex system modelling and through real data corresponding to a risk management tool in the mining sector.展开更多
A fuzzy set-based evaluation approach is demonstrated to assess the security risks for internet-banking System. The Internet-banking system is semi-formally described using Unified Modeling Language (UML) to specify...A fuzzy set-based evaluation approach is demonstrated to assess the security risks for internet-banking System. The Internet-banking system is semi-formally described using Unified Modeling Language (UML) to specify the behavior and state of the system on the base of analyzing the existing qualitative risk assessment methods. And a quantitative method based on fuzzy set is used to measure security risks of the system, A case study was performed on the WEB server of the Internet-banking System using fuzzy-set based assessment algorithm to quantitatively compute the security risk severity. The numeric result also provides a method to decide the most critical component which should amuse the system administrator enough attention to take the appropriate security measure or controls to alleviate the risk severity. The experiments show this method can be used to quantify the security properties for the Internet-banking System in practice.展开更多
In recent years, the coal safety has been become the urgent problem in China,and severe and fatal coal mine accidents occurred frequently.Must pay attention to coal safety management immediately, because the coal mine...In recent years, the coal safety has been become the urgent problem in China,and severe and fatal coal mine accidents occurred frequently.Must pay attention to coal safety management immediately, because the coal mine accidents not only caused serious economic losses to the country and people but also had negative impact on the society and politics.A closed loop management system was put forward to build to improve the coal safety management.The closed loop management system was formed four parts,identifying the hazard sources, classifying the hidden troubles hazard sources, the risk prealarm and risk control, and the evaluation system.展开更多
This paper establishes a risk assessment index system for the natural gas industrial chain. China's natural gas industrial chain is entering a stage of rapid growth. In order to guarantee healthy development of the n...This paper establishes a risk assessment index system for the natural gas industrial chain. China's natural gas industrial chain is entering a stage of rapid growth. In order to guarantee healthy development of the natural gas industrial chain, it is urgent to establish a risk alert system, which is based on a risk assessment index system. First of all, the risks of the natural gas industrial chain are defined in the paper; then the risk factors are analyzed according to the present status of the natural gas industrial chain, and five categories of risk factors are summarized: resource risk, transport risk, marketing risk, risk of unbalanced chain links, and environment risk. The paper presents the principles of the risk assessment index system. The natural gas industrial chain risk assessment index system is established with four levels and forty-six risk indices.展开更多
Gas disasters always restrict the tunnel constructions in mountain area, which becomes a major geological barrier against the development of underground engineering. China is rich in coal resources and has a large amo...Gas disasters always restrict the tunnel constructions in mountain area, which becomes a major geological barrier against the development of underground engineering. China is rich in coal resources and has a large amount of gas with a wide range of distribution. However, China experienced not only adverse effects on coal mining but also gas disasters in underground engineering construction, such as tunnels and chambers. With the increased number of tunnels passing through coal-bearing strata, the incidence of gas accidents is also rising. Therefore, the significance of preventing and mitigating gas disasters should be emphasized, and an effective risk assessment method for gas disasters should be established. On the basis of research on over 100 gas tunnels in China, a relatively ideal gas disaster risk assessment method and system for tunnels are established through the following measures. Firstly, geo-environmental conditions and gas situations were analyzed during construction. Secondly, qualitative analysis was combined with quantitative analysis. Finally, the influencing factors of gas disasters, including geological conditions, gas,and human factors, were investigated. The gas tunnel risk assessment system includes three levels:(1) the grading assessment of a gas tunnel during the planning stage,(2) the risk assessment of gas tunnel construction during the design and construction stages,(3) the gas tunnel outburst risk assessment during the coal uncovering stage. This system was applied to the dynamic assessment of gas disaster during the construction of the Zipingpu tunnel of Dujiangyan–Wenchuan Highway(in Sichuan, Southwest China). The assessment results were consistent with the actual excavation, which verified the rationality and feasibility of the system. The developed system was believed to be back-up and applied for risk assessment of gas disaster in the underground engineering construction.展开更多
This work details the simulation of tsunami waves generated by seaquakes in the Manila Trench and their effect on fixed oil and gas jacket platforms in waters offshore North Borneo. For this study, a four-leg living q...This work details the simulation of tsunami waves generated by seaquakes in the Manila Trench and their effect on fixed oil and gas jacket platforms in waters offshore North Borneo. For this study, a four-leg living quarter jacket platform located in a water depth of 63 m is modelled in SACS v5.3. Malaysia has traditionally been perceived to be safe from the hazards of earthquakes and tsunamis. Local design practices tend to neglect tsunami waves and include no such provisions. In 2004, a 9.3Mw seaquake occurred off the northwest coast of Aceh, which generated tsunami waves that caused destruction in Malaysia totalling US$ 25 million and 68 deaths. This event prompted an awareness of the need to study the reliability of fixed offshore platforms scattered throughout Malaysian waters. In this paper, we present a review of research on the seismicity of the Manila Trench, which is perceived to be high risk for Southeast Asia. From the tsunami numerical model TUNA-M2, we extract computer-simulated tsunami waves at prescribed grid points in the vicinity of the platforms in the region. Using wave heights as input, we simulate the tsunami using SACS v5.3 structural analysis software of offshore platforms, which is widely accepted by the industry. We employ the nonlinear solitary wave theory in our tsunami loading calculations for the platforms, and formulate a platform-specific risk quantification system. We then perform an intensive structural sensitivity analysis and derive a corresponding platform-specific risk rating model.展开更多
An exhaustive knowledge of flood risk in different spatial locations is essential for developing an effective flood mitigation strategy for a watershed. In the present study, a riskvulnerability analysis to flood is p...An exhaustive knowledge of flood risk in different spatial locations is essential for developing an effective flood mitigation strategy for a watershed. In the present study, a riskvulnerability analysis to flood is performed. Four components of vulnerability to flood: 1) physical, 2) economic, 3) infrastructure and 4) social;are evaluated individually using a Geographic Information System (GIS) environment. The proposed methodology estimates the impact on infrastructure vulnerability due to inundation of critical facilities, emer gency service stations and bridges. The components of vulnerability are combined to determine an overall vulnerability to flood. The exposures of land use/land cover and soil type (permeability) to flood are also considered to include their effects on severity of flood. The values of probability of occurrence of flood, vulnerability to flood, and exposures of land use and soil type to flood are used to finally compute flood risk at different locations in a watershed. The proposed methodology is implemented for six major damage centers in the Upper Thames River watershed, located in the SouthWestern Ontario, Canada to assess the flood risk. An information system is developed for systematic presentation of the flood risk, probability of occurrence of flood, vulnerability to flood, and exposures of land use and soil type to flood by postal code regions or Forward Sortation Areas (FSAs). The flood information system is designed to provide support for different users, i.e., general public, decisionmakers and water management professionals. An interactive analysis tool is developed within the information system to assist in evaluation of the flood risk in response to a change in land use pattern.展开更多
The main aim of this paper is to compare the stability, in terms of systemic risk, of conventional and Islamic banking systems. To this aim, we propose correlation network models for stock market returns based on grap...The main aim of this paper is to compare the stability, in terms of systemic risk, of conventional and Islamic banking systems. To this aim, we propose correlation network models for stock market returns based on graphical Gaussian distributions, which allows us to capture the contagion effects that move along countries. We also consider Bayesian graphical models, to account for model uncertainty in the measurement of financial systems interconnectedness. Our proposed model is applied to the Middle East and North Africa (MENA) region banking sector, characterized by the presence of both conventional and Islamic banks, for the period from 2007 to the beginning of 2014. Our empirical findings show that there are differences in the systemic risk and stability of the two banking systems during crisis times. In addition, the differences are subject to country specific effects that are amplified during crisis period.展开更多
Upper gastrointestinal haemorrhage (UGIH) remains a common medical emergency worldwide. It is increasingly recognised that early risk assessment is an important part of management, which helps direct appropriate patie...Upper gastrointestinal haemorrhage (UGIH) remains a common medical emergency worldwide. It is increasingly recognised that early risk assessment is an important part of management, which helps direct appropriate patient care and the timing of endoscopy. Several risk scores have been developed, most of which include endoscopic findings, although a minority do not. These scores were developed to identify various end-points including mortality, rebleeding or clinical intervention in the form of transfusion, endoscopic therapy or surgery. Recent studies have reported accurate identification of a very low risk group on presentation, using scores which require simple clinical or laboratory parameters only. This group may not require admission, but could be managed with early out-patient endoscopy. This article aims to describe the existing pre- and post-endoscopy risk scores for UGIH and assess the published data comparing them in the prediction of outcome. Recent data assessing their use in clinical practice, in particular the early identification of low-risk patients, are also discussed.展开更多
Risk assessment of distributed energy system often has uncertainty and subjective problems. The problems will have some impact on the results. To solve the problems, a method of improved fuzzy analytic hierarchy proce...Risk assessment of distributed energy system often has uncertainty and subjective problems. The problems will have some impact on the results. To solve the problems, a method of improved fuzzy analytic hierarchy process is proposed. By using the fuzzy analytic hierarchy process method, a hierarchical analysis model is established. And then according to the given judgment matrix of each index layer, we calculate whether it meets the consistency condition. And then if the judgment matrix does not meet the consistency condition, the problem will be solved by the improving of particle swarm optimization (PSO) with Kalman filter. The practice in the distributed energy system shows that the method can not only fully reflect the fuzziness of assessment elements and process, but also reduce the influence of individual subjective factors and better evaluation results can be achieved.展开更多
文摘The significance of this study lies in its exploration of the advanced applications of Geographic Information Systems (GIS) in assessing urban flood risks, with a specific focus on Midar, Morocco. This research is pivotal as it showcases that GIS technology is not just a tool for mapping, but a critical component in urban planning and emergency management strategies. By meticulously identifying and mapping flood-prone areas in Midar, the study provides invaluable insights into the potential vulnerabilities of urban landscapes to flooding. Moreover, this research demonstrates the practical utility of GIS in mitigating material losses, a significant concern in flood-prone urban areas. The proactive approach proposed in this study, centered around the use of GIS, aims to safeguard Midar’s population and infrastructure from the devastating impacts of floods. This approach serves as a model for other urban areas facing similar challenges, highlighting the indispensable role of GIS in disaster preparedness and response. Overall, the study underscores the transformative potential of GIS in enhancing urban resilience, making it a crucial tool in the fight against natural disasters like floods.
基金supported by State Key Fundamental Research Program of China(Grant No.50639070)the Knowledge Innovation Project of the Chinese Academy of Sciences(Grant No.KKCX1-YW-03)
文摘The Wenchuan Earthquake of May 12,2008 triggered large numbers of geo-hazards.The heavy rain on 13 August 2010 triggered debris flows with total volume of more than 6 million cubic meters and the debris flows destroyed 500 houses and infrastructure built after the Wenchuan Earthquake.The study area Qingping Town was located in the northwestern part of the Sichuan Basin of China,which needs the second reconstructions and the critical evaluation of debris flow.This study takes basin as the study unit and defines collapse,landslide and debris flow hazard as a geo-hazard system.A multimode system composed of principal series system and secondary parallel system were established to evaluate the hazard grade of debris flow in 138 drainage basins of Qingping Town.The evaluation result shows that 30.43% of study basins(42 basins) and 24.58% of study area,are in extremely high or high hazard grades,and both percentage of basin quantity and percentage of area in different hazard grades decrease with the increase of hazard grade.According to the geo-hazard data from the interpretation of unmanned plane image with a 0.5-m resolution and field investigation after the Wenchuan Earthquake and 8.13 Big Debris Flow,the ratio of landslides and collapses increased after the Wenchuan Earthquake and the ratios of extremely high or high hazard grades were more than moderate or low hazard grades obviously.23 geo-hazards after8.13 Big Debris Flow in Qingping town region all occurred in basins with extremely high or high hazard grades,and 9 debris flows were in basins with extremely high hazard grade.The model of multimode system for critical evaluation could forecast not only the collapse and landslide but also the debris flow precisely when the basin was taken as the study unit.
基金Project 2002CB412705 supported by the Major State Basic Research Development Program (973) of China
文摘Modern surface mines, either mono-system or multi-systems, need a large fleet of equipment consisting of excavators, loaders, haulers and auxiliary machines. Presently, the complexity of the system, the interference between sub-systems and the lag in management skills has been a bottle neck for improving productivity of the system. Based on the fact that the traditional tools for safety analysis have been insufficient to evaluate systematically and dynamically the safety risks, this paper tries to create a virtual reality tool consisting of human, machine and mines, using Pro/E and the 3D MAX software in order to evaluate visually the operations of typical mining equipment, such as the bucket wheel excavator (BWE), the shovel, the truck and the dragline. Within this virtual world, the behavior of the system, such as interaction, interference and potential risk can be replayed and reviewed visually. The objective of the study is to identify the critical safety issues of the system and to provide a convenient and powerful tool for safety training and safety management.
文摘Expert systems are methods that can cope with rock engineer’s expertise effectively.An expert system on assessing rockburst risks for South African deep gold mines is described.Expertise was represented by rules, frames and mathematical models integratively. About 950 rules was built in the knowledge base, which can be learned by the suggested learning algorithm. A new uncertain reasoning algorithm was proposed. According to the features such as depth below surface, energy release rate (ERR), excess shear stress (ESS), geological structure, face angle with structure, distance from structure, extent of mining, mining type, width of bracket pillar, stope width, local support, regional support and gully support, rockburst risk is assessed either "Low", "Moderate", "High" or "Severe". A computer program system was developed by Turbo Prolog. The results of testing cases show its applicability of the system.
基金supported by the National Natural Science Foundation of China(Grant Nos.91547111,51379027&51409043)Natural Science Foundation of Liaoning Province(Grant No.2015020608)National Science and Technology Pillar Program during the Twelfth Five-year Plan Period(Grant No.2015BAB07B03)
文摘Flood control system risk evaluation is an effective measure for flood risk management and decisions.In order to make better flood risk decisions and thereby improve social and economic benefits,the flood control risk evaluation index system should be built to quantify and normalize flood risk effectively and efficiently.Because the current evaluation index has the binary miscibility characteristic of fuzziness and clarity,this paper establishes a new flood control system risk evaluation method based on the theory of variable sets(VS).Through a comparison of flood control risk evaluation with variable fuzzy sets(VFS) in the same basin flood control system risk evaluation,it is revealed that the new method,i.e.,flood control risk evaluation with variable fuzzy/clear mixture sets(variable sets),will be reasonable in all cases.Finally,in one case study,i.e.,the flood control system risk evaluation of Fengman Reservoir Basin,which is located in the southeast central of Jilin Province in China,the risk evaluation levels for each county in the basin as well as the whole flood risk distribution map of the basin could be provided with the new method.This provides useful information for basin flood control planning and design.
基金supported by the National Natural Science Foundation of China(81372883,81001052)Natural Science Foundation of Guangdong Province,China(2015A030313020 and 8151008901000043)+3 种基金Science and Technology Planning Project of Guangdong Province,China(2011B031800222)Young Talents Key Project of Sun Yat?sen University(2015ykzd13,to Qing-qing Cai)Young Talents Project of Sun Yat-sen University(11ykpy56,to Qing-qing Cai)the Sister Institution Network Fund of MD Anderson Cancer Center(to Qing-qing Cai and Hui-Rao)
文摘Background: In patients with difuse large B?cell lymphoma(DLBCL), central nervous system(CNS) relapse is uncom?mon but is nearly always fatal. This study aimed to determine the risk factors for CNS relapse in DLBCL patients and to evaluate the eicacy of rituximab and intrathecal chemotherapy prophylaxis for CNS relapse reduction.Methods: A total of 511 patients with newly diagnosed DLBCL treated at the Sun Yat?sen University Cancer Center between January 2003 and December 2012 were included in the study. Among these patients, 376 received R?CHOP regimen(rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) as primary treatment, and 135 received CHOP regimen(cyclophosphamide, doxorubicin, vincristine, and prednisone) as primary treatment. Intrathe?cal chemotherapy prophylaxis(methotrexate plus cytarabine) was administered to those who were deemed at high risk for CNS relapse. In the entire cohort and in the R?CHOP set in particular, the Kaplan–Meier method coupled with the log?rank test was used for univariate analysis, and the Cox proportional hazards model was used for multivariate analysis. Diferences were evaluated using a two?tailed test, and P < 0.05 was considered signiicant.Results: At a median follow?up of 46 months, 25(4.9%) patients experienced CNS relapse. There was a trend of reduced occurrence of CNS relapse in patients treated with rituximab; the 3?year cumulative CNS relapse rates were 7.1% in CHOP group and 2.7% in R?CHOP group(P = 0.045). Intrathecal chemotherapy prophylaxis did not confer much beneit in terms of preventing CNS relapse. Bone involvement [hazard ratio(HR) = 4.21, 95% conidence interval(CI) 1.38–12.77], renal involvement(HR = 3.85, 95% CI 1.05–14.19), alkaline phosphatase(ALP) >110 U/L(HR = 3.59, 95% CI 1.25–10.34), serum albumin(ALB) <35 g/L(HR = 3.63, 95% CI 1.25–10.51), treatment with rituxi?mab(HR = 0.34, 95% CI 0.12–0.96), and a time to complete remission ≤ 108 days(HR = 0.22, 95% CI 0.06–0.78) were independent predictive factors for CNS relapse in the entire cohort. Bone involvement(HR = 4.44, 95% CI 1.08–18.35), bone marrow involvement(HR = 11.70, 95% CI 2.24–60.99), and renal involvement(HR = 10.83, 95% CI 2.27–51.65) were independent risk factors for CNS relapse in the R?CHOP set.Conclusions: In the present study, rituximab decreased the CNS relapse rate of DLBCL, whereas intrathecal chemo?therapy prophylaxis alone was not suicient for preventing CNS relapse. Serum levels of ALB and ALP, and the time to complete remission were new independent predictive factors for CNS relapse in the patients with DLBCL. In the patients received R?CHOP regimen, a trend of increased CNS relapse was found to be associated with extranodal lesions.
基金supported by National Social Science Fund project"The study of carbon finance mechanisms supporting the development of low-carbon economy"[grant number10CJY076]Beijing Philosophy and Social Science Project"The market pricing mechanism and price management strategy of carbon emission in Beijing"[grant number 13JGC068]+2 种基金National Science&Technology Pillar Program"The research of key support policies and techniques in green low-carbon development in China"[grant number 2012BAC20B08]grant project from China Clean Development Mechanism Fund in the Ministry of Finance:"The study of financing,strategies,mechanism and policy system addressing climate change in China"[grant number 2012064]the project of research innovation teams in Central University of Finance and Economics and China Financial Development Collaborative Innovation Center
文摘Currently,the global carbon trading systems are fragmented and belong to different governments or are under the jurisdiction of different regions,resulting in a series of new problems,such as how to link dispersed trading systems,how to compare the emission reduction of various markets and other issues.Since the development of the international carbon market is relatively immature with uncertain life expectancy and volatility during its short history,and there is a lack of quantitative data on the long-term record,the market could provide few risk management tools.Meanwhile,with the launches of China's regional carbon trading pilots in seven provinces since 2013 and combined with the national voluntary emission trading system,carbon trading will become an important mechanism for China in achieving its emission reduction target.In the first stage,the carbon finance market is at least faced with mechanism design risks,market supply risks and compliance risks.Therefore,to secure the development of the carbon market and for public interest,relevant government departments of China should identify the risks facing the market and should make the basic principles and goals,such as ensuring effective trading and pricing mechanisms to avoid fraud and price manipulation,and balancing transparency and confidentiality of information.Consequently,the governments should develop a comprehensive carbon finance regulatory system covering regulatory legislation,regulatory institutions and their authorities,regulatory scope as well as regulatory objects.
文摘Related to complexity, there is a wide diversity of concepts, ranging from ‘‘systemic" to ‘‘complex", implying a need for a unified terminology. Per different authors, the main drivers of complexity can be found in human behaviour and uncertainty. This complexity, structural or dynamic can be organizational, technological, or nested in their relationship. ISO international standard 31000:2009 definition of risk management ‘‘coordinated activities to direct and control an organization with regard to risk", when applied to economic sectors, industry, services, project, or activity, it requires the use of models or theories as guidelines. Therefore, as its basic elements comprehend human behaviour and/or uncertainty, risk management to be effective and adapted as much as possible to reality, must be operational within complex systems, as already demonstrated in different R&D environments. Risk management faces demanding challenges when approaching specific and endogenous needs, such as the mining sector. This paper presents a multivariable function analysis methodology approach based on complex system modelling and through real data corresponding to a risk management tool in the mining sector.
基金Supported by the National Natural Science Foun-dation of China (2002AA142150)
文摘A fuzzy set-based evaluation approach is demonstrated to assess the security risks for internet-banking System. The Internet-banking system is semi-formally described using Unified Modeling Language (UML) to specify the behavior and state of the system on the base of analyzing the existing qualitative risk assessment methods. And a quantitative method based on fuzzy set is used to measure security risks of the system, A case study was performed on the WEB server of the Internet-banking System using fuzzy-set based assessment algorithm to quantitatively compute the security risk severity. The numeric result also provides a method to decide the most critical component which should amuse the system administrator enough attention to take the appropriate security measure or controls to alleviate the risk severity. The experiments show this method can be used to quantify the security properties for the Internet-banking System in practice.
基金Supported by the Research Fund for the Doctoral Program of Higher Education of China(20090095110001)the Ministry of Education Humanities and Social Science(08JA630083)
文摘In recent years, the coal safety has been become the urgent problem in China,and severe and fatal coal mine accidents occurred frequently.Must pay attention to coal safety management immediately, because the coal mine accidents not only caused serious economic losses to the country and people but also had negative impact on the society and politics.A closed loop management system was put forward to build to improve the coal safety management.The closed loop management system was formed four parts,identifying the hazard sources, classifying the hidden troubles hazard sources, the risk prealarm and risk control, and the evaluation system.
基金This research is supported by CNPC Innovation Foundation.
文摘This paper establishes a risk assessment index system for the natural gas industrial chain. China's natural gas industrial chain is entering a stage of rapid growth. In order to guarantee healthy development of the natural gas industrial chain, it is urgent to establish a risk alert system, which is based on a risk assessment index system. First of all, the risks of the natural gas industrial chain are defined in the paper; then the risk factors are analyzed according to the present status of the natural gas industrial chain, and five categories of risk factors are summarized: resource risk, transport risk, marketing risk, risk of unbalanced chain links, and environment risk. The paper presents the principles of the risk assessment index system. The natural gas industrial chain risk assessment index system is established with four levels and forty-six risk indices.
基金support by the National Natural Science Foundation of China (Grant No. 41302244)
文摘Gas disasters always restrict the tunnel constructions in mountain area, which becomes a major geological barrier against the development of underground engineering. China is rich in coal resources and has a large amount of gas with a wide range of distribution. However, China experienced not only adverse effects on coal mining but also gas disasters in underground engineering construction, such as tunnels and chambers. With the increased number of tunnels passing through coal-bearing strata, the incidence of gas accidents is also rising. Therefore, the significance of preventing and mitigating gas disasters should be emphasized, and an effective risk assessment method for gas disasters should be established. On the basis of research on over 100 gas tunnels in China, a relatively ideal gas disaster risk assessment method and system for tunnels are established through the following measures. Firstly, geo-environmental conditions and gas situations were analyzed during construction. Secondly, qualitative analysis was combined with quantitative analysis. Finally, the influencing factors of gas disasters, including geological conditions, gas,and human factors, were investigated. The gas tunnel risk assessment system includes three levels:(1) the grading assessment of a gas tunnel during the planning stage,(2) the risk assessment of gas tunnel construction during the design and construction stages,(3) the gas tunnel outburst risk assessment during the coal uncovering stage. This system was applied to the dynamic assessment of gas disaster during the construction of the Zipingpu tunnel of Dujiangyan–Wenchuan Highway(in Sichuan, Southwest China). The assessment results were consistent with the actual excavation, which verified the rationality and feasibility of the system. The developed system was believed to be back-up and applied for risk assessment of gas disaster in the underground engineering construction.
基金Universiti Teknologi PETRONAS Research Grant(No.0153B2-A44)
文摘This work details the simulation of tsunami waves generated by seaquakes in the Manila Trench and their effect on fixed oil and gas jacket platforms in waters offshore North Borneo. For this study, a four-leg living quarter jacket platform located in a water depth of 63 m is modelled in SACS v5.3. Malaysia has traditionally been perceived to be safe from the hazards of earthquakes and tsunamis. Local design practices tend to neglect tsunami waves and include no such provisions. In 2004, a 9.3Mw seaquake occurred off the northwest coast of Aceh, which generated tsunami waves that caused destruction in Malaysia totalling US$ 25 million and 68 deaths. This event prompted an awareness of the need to study the reliability of fixed offshore platforms scattered throughout Malaysian waters. In this paper, we present a review of research on the seismicity of the Manila Trench, which is perceived to be high risk for Southeast Asia. From the tsunami numerical model TUNA-M2, we extract computer-simulated tsunami waves at prescribed grid points in the vicinity of the platforms in the region. Using wave heights as input, we simulate the tsunami using SACS v5.3 structural analysis software of offshore platforms, which is widely accepted by the industry. We employ the nonlinear solitary wave theory in our tsunami loading calculations for the platforms, and formulate a platform-specific risk quantification system. We then perform an intensive structural sensitivity analysis and derive a corresponding platform-specific risk rating model.
文摘An exhaustive knowledge of flood risk in different spatial locations is essential for developing an effective flood mitigation strategy for a watershed. In the present study, a riskvulnerability analysis to flood is performed. Four components of vulnerability to flood: 1) physical, 2) economic, 3) infrastructure and 4) social;are evaluated individually using a Geographic Information System (GIS) environment. The proposed methodology estimates the impact on infrastructure vulnerability due to inundation of critical facilities, emer gency service stations and bridges. The components of vulnerability are combined to determine an overall vulnerability to flood. The exposures of land use/land cover and soil type (permeability) to flood are also considered to include their effects on severity of flood. The values of probability of occurrence of flood, vulnerability to flood, and exposures of land use and soil type to flood are used to finally compute flood risk at different locations in a watershed. The proposed methodology is implemented for six major damage centers in the Upper Thames River watershed, located in the SouthWestern Ontario, Canada to assess the flood risk. An information system is developed for systematic presentation of the flood risk, probability of occurrence of flood, vulnerability to flood, and exposures of land use and soil type to flood by postal code regions or Forward Sortation Areas (FSAs). The flood information system is designed to provide support for different users, i.e., general public, decisionmakers and water management professionals. An interactive analysis tool is developed within the information system to assist in evaluation of the flood risk in response to a change in land use pattern.
文摘The main aim of this paper is to compare the stability, in terms of systemic risk, of conventional and Islamic banking systems. To this aim, we propose correlation network models for stock market returns based on graphical Gaussian distributions, which allows us to capture the contagion effects that move along countries. We also consider Bayesian graphical models, to account for model uncertainty in the measurement of financial systems interconnectedness. Our proposed model is applied to the Middle East and North Africa (MENA) region banking sector, characterized by the presence of both conventional and Islamic banks, for the period from 2007 to the beginning of 2014. Our empirical findings show that there are differences in the systemic risk and stability of the two banking systems during crisis times. In addition, the differences are subject to country specific effects that are amplified during crisis period.
文摘Upper gastrointestinal haemorrhage (UGIH) remains a common medical emergency worldwide. It is increasingly recognised that early risk assessment is an important part of management, which helps direct appropriate patient care and the timing of endoscopy. Several risk scores have been developed, most of which include endoscopic findings, although a minority do not. These scores were developed to identify various end-points including mortality, rebleeding or clinical intervention in the form of transfusion, endoscopic therapy or surgery. Recent studies have reported accurate identification of a very low risk group on presentation, using scores which require simple clinical or laboratory parameters only. This group may not require admission, but could be managed with early out-patient endoscopy. This article aims to describe the existing pre- and post-endoscopy risk scores for UGIH and assess the published data comparing them in the prediction of outcome. Recent data assessing their use in clinical practice, in particular the early identification of low-risk patients, are also discussed.
文摘Risk assessment of distributed energy system often has uncertainty and subjective problems. The problems will have some impact on the results. To solve the problems, a method of improved fuzzy analytic hierarchy process is proposed. By using the fuzzy analytic hierarchy process method, a hierarchical analysis model is established. And then according to the given judgment matrix of each index layer, we calculate whether it meets the consistency condition. And then if the judgment matrix does not meet the consistency condition, the problem will be solved by the improving of particle swarm optimization (PSO) with Kalman filter. The practice in the distributed energy system shows that the method can not only fully reflect the fuzziness of assessment elements and process, but also reduce the influence of individual subjective factors and better evaluation results can be achieved.