考虑突发事件下的应急资源调度成本和复杂风险变量随机模拟情形,以满足各灾害点的需求最小化调度成本为目标,分析风险变量对运输工具的选择影响而引起的成本变化以及在运输过程中物资损失所引起的费用变化;在一系列模型假设和定义下,构...考虑突发事件下的应急资源调度成本和复杂风险变量随机模拟情形,以满足各灾害点的需求最小化调度成本为目标,分析风险变量对运输工具的选择影响而引起的成本变化以及在运输过程中物资损失所引起的费用变化;在一系列模型假设和定义下,构建基于多灾害点的应急供应调度模型,并结合随机模拟与基于细菌趋化的粒子群(particle swarm optimization based on bacterial chemotaxis,PSOBC)算法进行研究,实现最小化费用成本的目标;最后通过算例分析验证了所建模型和算法是有效和可行的。展开更多
[Objective] The aim was to research application of revised puff trajectory model in atmospheric environmental risks simulation.[Method] In the research,theory of puff trajectory model for pollution diffusion in atmosp...[Objective] The aim was to research application of revised puff trajectory model in atmospheric environmental risks simulation.[Method] In the research,theory of puff trajectory model for pollution diffusion in atmosphere in urban areas was analyzed and CALPUFF,a revised puff trajectory model,was applied in prediction on atmospheric environmental risks in Xining City.[Result] The simple puff trajectory model can not be applied for long-distance transport or in complex terrain and airflow field.In contrast,CALPUFF would be applied in urban areas,and complex terrain or underlying surface.With high resolution ratio,it would depict the beginning condition and detailed distribution of pollutants transport and diffusion.For prediction on atmospheric environmental risks in Xining City,northwest wind dominated in Huangshui Valley;north wind dominated in Beichuan Valley;temperature inversion occurred at high altitude.These had a significant effect on the downwind direction in Xining urban district.The simulation results indicated that puffs usually spread along Huangshui Valley and some non-steady phenomena occurred,such as blocking effect by mountains,deformation of puff by airflow field in ridges and influence of valley wind.[Conclusion] The research is of significance for precise prediction on characters,influence and extent of atmospheric environmental risks in cities.展开更多
Endoscopic ultrasonography (EUS) has gained wide acceptance as an important, minimally invasive diagnostic tool in gastroenterology, pulmonology, visceral surgery and oncology. This review focuses on data regarding ri...Endoscopic ultrasonography (EUS) has gained wide acceptance as an important, minimally invasive diagnostic tool in gastroenterology, pulmonology, visceral surgery and oncology. This review focuses on data regarding risks and complications of non-interventional diagnostic EUS and EUS-guided fine-needle biopsy (EUS-FNB). Measures to improve the safety of EUS und EUS-FNB will be discussed. Due to the specific mechanical properties of echoendoscopes in EUS, there is a low but noteworthy risk of perforation. To minimize this risk, endoscopists should be familiar with the specific features of their equipment and their patients' specific anatomical situations (e.g., tumor stenosis, diverticula). Most diagnostic EUS complications occur during EUS-FNB. Pain, acute pancreatitis, infection and bleeding are the primary adverse effects, occurring in 1% to 2% ofpatients. Only a few cases of needle tract seeding and peritoneal dissemination have been reported. The mortality associated with EUS and EUS-FNB is 0.02%. The risks associated with EUS-FNB are affected by endoscopist experience and target lesion. EUS-FNB of cystic lesions is associated with an increased risk of infection and hemorrhage. Peri-interventional antibiotics are recommended to prevent cyst infection. Adequate education and training, as well consideration of contraindications, are essential to minimize the risks of EUS and EUS-FNB. Restricting EUS-FNB only to patients in whom the cytopathological results may be expected to change the course of management is the best way of reducing the number of complications.展开更多
According to news reports on severe earthquakes since 2008,a total of 51 cases with magnitudes of 6.0 or above were analyzed,and 14 frequently occurring secondary disasters were identified.A disaster chain model was d...According to news reports on severe earthquakes since 2008,a total of 51 cases with magnitudes of 6.0 or above were analyzed,and 14 frequently occurring secondary disasters were identified.A disaster chain model was developed using principles from complex network theory.The vulnerability and risk level of each edge in this model were calculated,and high-risk edges and disaster chains were identified.The analysis reveals that the edge“floods→building collapses”has the highest vulnerability.Implementing measures to mitigate this edge is crucial for delaying the spread of secondary disasters.The highest risk is associated with the edge“building collapses→casualties,”and increased risks are also identified for chains such as“earthquake→building collapses→casualties,”“earthquake→landslides and debris flows→dammed lakes,”and“dammed lakes→floods→building collapses.”Following an earthquake,the prompt implementation of measures is crucial to effectively disrupt these chains and minimize the damage from secondary disasters.展开更多
The world is entering a highly uncertain“risk society.”Risk is a major feature of contemporary society,changing society’s operational logic and rules;society’s values and modes of behavior are being systematically...The world is entering a highly uncertain“risk society.”Risk is a major feature of contemporary society,changing society’s operational logic and rules;society’s values and modes of behavior are being systematically reconstructed,and global governance is evolving into the governance of a“world risk society.”At present,global risk governance is highly fragmented and inefficient,and the existing modes of public management and international governance are still unsuited to the requirements of risk society governance.Modern society is an intricate system of endogenous complexity,unpredictability and fragility.Complexity is the fundamental mechanism driving the formation of global risk society,a society whose governance rests on the paradigm of complexity and on Chinese participation.Research on the complexity mechanism behind the formation of world risk society and the construction of values,culture and mechanisms that address its governance is significant for both theory and practice,enabling us to develop synergetic governance and an antifragile capacity that will identify and overcome risks.展开更多
文摘考虑突发事件下的应急资源调度成本和复杂风险变量随机模拟情形,以满足各灾害点的需求最小化调度成本为目标,分析风险变量对运输工具的选择影响而引起的成本变化以及在运输过程中物资损失所引起的费用变化;在一系列模型假设和定义下,构建基于多灾害点的应急供应调度模型,并结合随机模拟与基于细菌趋化的粒子群(particle swarm optimization based on bacterial chemotaxis,PSOBC)算法进行研究,实现最小化费用成本的目标;最后通过算例分析验证了所建模型和算法是有效和可行的。
文摘[Objective] The aim was to research application of revised puff trajectory model in atmospheric environmental risks simulation.[Method] In the research,theory of puff trajectory model for pollution diffusion in atmosphere in urban areas was analyzed and CALPUFF,a revised puff trajectory model,was applied in prediction on atmospheric environmental risks in Xining City.[Result] The simple puff trajectory model can not be applied for long-distance transport or in complex terrain and airflow field.In contrast,CALPUFF would be applied in urban areas,and complex terrain or underlying surface.With high resolution ratio,it would depict the beginning condition and detailed distribution of pollutants transport and diffusion.For prediction on atmospheric environmental risks in Xining City,northwest wind dominated in Huangshui Valley;north wind dominated in Beichuan Valley;temperature inversion occurred at high altitude.These had a significant effect on the downwind direction in Xining urban district.The simulation results indicated that puffs usually spread along Huangshui Valley and some non-steady phenomena occurred,such as blocking effect by mountains,deformation of puff by airflow field in ridges and influence of valley wind.[Conclusion] The research is of significance for precise prediction on characters,influence and extent of atmospheric environmental risks in cities.
文摘Endoscopic ultrasonography (EUS) has gained wide acceptance as an important, minimally invasive diagnostic tool in gastroenterology, pulmonology, visceral surgery and oncology. This review focuses on data regarding risks and complications of non-interventional diagnostic EUS and EUS-guided fine-needle biopsy (EUS-FNB). Measures to improve the safety of EUS und EUS-FNB will be discussed. Due to the specific mechanical properties of echoendoscopes in EUS, there is a low but noteworthy risk of perforation. To minimize this risk, endoscopists should be familiar with the specific features of their equipment and their patients' specific anatomical situations (e.g., tumor stenosis, diverticula). Most diagnostic EUS complications occur during EUS-FNB. Pain, acute pancreatitis, infection and bleeding are the primary adverse effects, occurring in 1% to 2% ofpatients. Only a few cases of needle tract seeding and peritoneal dissemination have been reported. The mortality associated with EUS and EUS-FNB is 0.02%. The risks associated with EUS-FNB are affected by endoscopist experience and target lesion. EUS-FNB of cystic lesions is associated with an increased risk of infection and hemorrhage. Peri-interventional antibiotics are recommended to prevent cyst infection. Adequate education and training, as well consideration of contraindications, are essential to minimize the risks of EUS and EUS-FNB. Restricting EUS-FNB only to patients in whom the cytopathological results may be expected to change the course of management is the best way of reducing the number of complications.
基金National Key Research and Development Program of China(No.2022YFC3803000).
文摘According to news reports on severe earthquakes since 2008,a total of 51 cases with magnitudes of 6.0 or above were analyzed,and 14 frequently occurring secondary disasters were identified.A disaster chain model was developed using principles from complex network theory.The vulnerability and risk level of each edge in this model were calculated,and high-risk edges and disaster chains were identified.The analysis reveals that the edge“floods→building collapses”has the highest vulnerability.Implementing measures to mitigate this edge is crucial for delaying the spread of secondary disasters.The highest risk is associated with the edge“building collapses→casualties,”and increased risks are also identified for chains such as“earthquake→building collapses→casualties,”“earthquake→landslides and debris flows→dammed lakes,”and“dammed lakes→floods→building collapses.”Following an earthquake,the prompt implementation of measures is crucial to effectively disrupt these chains and minimize the damage from secondary disasters.
基金supported by grants from the Major Program of the National Social Science Fund(14ZDA06)the National Natural Science Foundation(71271159)
文摘The world is entering a highly uncertain“risk society.”Risk is a major feature of contemporary society,changing society’s operational logic and rules;society’s values and modes of behavior are being systematically reconstructed,and global governance is evolving into the governance of a“world risk society.”At present,global risk governance is highly fragmented and inefficient,and the existing modes of public management and international governance are still unsuited to the requirements of risk society governance.Modern society is an intricate system of endogenous complexity,unpredictability and fragility.Complexity is the fundamental mechanism driving the formation of global risk society,a society whose governance rests on the paradigm of complexity and on Chinese participation.Research on the complexity mechanism behind the formation of world risk society and the construction of values,culture and mechanisms that address its governance is significant for both theory and practice,enabling us to develop synergetic governance and an antifragile capacity that will identify and overcome risks.
