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The First Reported Case of Co-Infection with Neisseria Meningitidis and Bordetella Pertussis in the Cerebrospinal Fluid Specimen of a Normal Four-Year-Old Child
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作者 XIA Xian LI Guo Ming +7 位作者 TANG Yi WANG Si Quan HE Fei JIANG Yong Zhong YANG Hong Mei JIANG Hong Lin LYU Jing MAO Ling Feng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第4期432-435,共4页
Pertussis is an acute and highly contagious respiratory disease caused by Bordetella pertussis(B.pertussis),which occurs in people of all ages and is most dangerous for young children,especially infants.The introducti... Pertussis is an acute and highly contagious respiratory disease caused by Bordetella pertussis(B.pertussis),which occurs in people of all ages and is most dangerous for young children,especially infants.The introduction of whole-cell pertussis vaccines(wPVs)in the 1950s dramatically reduced the incidence of pertussis worldwide[1].However,over the past two decades,many studies have reported the resurgence of pertussis in different countries[2].Epidemiological surveillance in Hubei Province over the last 3 years revealed a clear increasing trend in the incidence of pertussis during the coronavirus disease 2019(COVID-19)epidemic. 展开更多
关键词 PERTUSSIS DANGEROUS HUBEI
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Research on safety control technology of high-speed railway combined test based on threatening event analysis
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作者 Xin Bai Jiaxu Chen 《Railway Sciences》 2024年第6期731-745,共15页
Purpose–Safety management is a key point and poses a challenge in joint testing.To detect and address potential accidents’hidden dangers early,this paper conducts research on the safety control technology for high-s... Purpose–Safety management is a key point and poses a challenge in joint testing.To detect and address potential accidents’hidden dangers early,this paper conducts research on the safety control technology for high-speed railway joint tests by incorporating the concept of hazardous events.Design/methodology/approach–Aiming at ensuring the safety of high-speed railway combined inspections and trials,this paper starts from the dual prevention mechanism.It introduces the concept of threatening events,defines them and analyzes the differences between threatening events and railway accidents.The paper also proposes a cause model for threatening events in high-speed railway combined inspections and trials,based on three types of hazard sources.Furthermore,it conducts research on the control strategies for these threatening events.Findings–The research on safety control technology for high-speed railway combined operation and testing,based on the analysis of threatened events,offers a new perspective for safety management in these operations.It also provides theoretical and practical support for the transition from passive prevention to active risk pre-control,which holds significant theoretical and practical value.Originality/value–The innovation mainly includes the following three aspects:(1)Building on the traditional dual prevention mechanism,which includes risk hierarchical management and control as well as hidden danger investigation and management,a triple prevention mechanism is proposed.This new mechanism adds the management of threatening events as the third line of defense.The aim is to more comprehensively identify and address potential security risks,thereby enhancing the efficiency and effectiveness of security management.(2)In this paper,the definition of a railway threatening event is clarified,and the causative model of a high-speed railway threatening event based on three kinds of danger sources is proposed.(3)This paper puts forward the control strategy of the high-speed railway combined operation and trial,which includes five key links:identification,reporting,analysis,rectification and feedback,which provides a new perspective for the safety management of the high-speed railway combined operation and trial and has important theoretical and application value. 展开更多
关键词 High-speed railway Joint investigation and test Threatening event Source of danger Control strategy
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Quantifying the Impact of In-Cab Alerts on Truck Speed Reductions in Ohio
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作者 Jairaj Desai Jijo K. Mathew Darcy M. Bullock 《Journal of Transportation Technologies》 2024年第3期273-288,共16页
In-cab alerts warn commercial vehicle drivers of upcoming roadway incidents, slowdowns and work zone construction activities. This paper reports on a study evaluating the driver response to in-cab alerts in Ohio. Driv... In-cab alerts warn commercial vehicle drivers of upcoming roadway incidents, slowdowns and work zone construction activities. This paper reports on a study evaluating the driver response to in-cab alerts in Ohio. Driver response was evaluated by measuring the statistical trends of vehicle speeds after the in-cab alerts were received. Vehicle speeds pre and post in-cab alert were collected over a 47 day period in the fall of 2023 for trucks traveling on interstate roadways in Ohio. Results show that approximately 22% of drivers receiving Dangerous Slowdown alerts had reduced their speeds by at least 5 mph 30 seconds after receiving such an alert. Segmenting this analysis by speed found that of vehicles traveling at or above 70 mph at the time of alerting, 26% reduced speeds by at least 5 mph. These speed reductions suggest drivers taking actional measures after receiving alerts. Future studies will involve further analysis on the impact of the types of alerts shown, roadway characteristics and overall traffic conditions on truck speeds passing through work zones. 展开更多
关键词 In-Cab Alerts Connected Truck Data Driver Alerts Dangerous Slowdowns
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How Dangerous!
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作者 魏子博 陈传光(指导) 《中学生英语》 2024年第2期7-7,共1页
This morning I came across something dangerous on my way to school,which nearly injured me or even made me lose my life.
关键词 SOMETHING INJURED DANGEROUS
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School Rules
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作者 肖丽芸 刘婷(指导) 《中学生英语》 2024年第5期7-7,共1页
Every school has its rules.In our school,there are many rules,too.For example,we must go to school on time.We mustn't run in the hallways.We mustn't eat in the classroom but we can eat in the canteen.We mustn&... Every school has its rules.In our school,there are many rules,too.For example,we must go to school on time.We mustn't run in the hallways.We mustn't eat in the classroom but we can eat in the canteen.We mustn't take cell phones and dangerous goods to school.We have to wear the school uniforms when we are at school. 展开更多
关键词 TOO DANGEROUS CLASSROOM
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Costa Rica's Cave of Death is lethal to any creature
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作者 高坚 《疯狂英语(新读写)》 2024年第9期52-53,77,78,共4页
Activity 1.Think about the following questions and write down your answers before reading the text.1.What do you think might be the most dangerous thing in exploring such mysterious caves?2.If you could discover a new... Activity 1.Think about the following questions and write down your answers before reading the text.1.What do you think might be the most dangerous thing in exploring such mysterious caves?2.If you could discover a new cave with unique features,what kind of features would you hope to find? 展开更多
关键词 features SUCH DANGEROUS
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汉译英训练(34)
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作者 李运兴 《大学英语》 2017年第4期62-64,共3页
暗途许地山"我的朋友,且等一等,待我为你点着灯,才走。"*吾威~1听见他的朋友这样说,便笑道:"哈哈,均哥,你以我为女人么?女人在夜间走路才要用火;男子,又何必呢?不用张罗,我空手回去罢——省得以后还要给你送灯回来。"吾威的村... 暗途许地山"我的朋友,且等一等,待我为你点着灯,才走。"*吾威~1听见他的朋友这样说,便笑道:"哈哈,均哥,你以我为女人么?女人在夜间走路才要用火;男子,又何必呢?不用张罗,我空手回去罢——省得以后还要给你送灯回来。"吾威的村庄和均哥所住的地方隔着几重山,*路途崎岖得很厉害~2。*若是夜间要走那条路~3,无论是谁,都得带灯。 展开更多
关键词 许地山 给你 FRIEND MOUNTAINS EVERYWHERE night weather DANGER walking VILLAGE
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高一(上)词语辨析练习(英文)
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作者 郝昌明 《中学生英语(高中版)》 2008年第34期19-21,共3页
Unit 7 1.include/contain (1)I can’t go home now,because my task _______cleaning the windows. (2)As we all know,sea water______ much salt. 2.give in/give up (1)You must______smoking,because it is dangerous for us. (2)... Unit 7 1.include/contain (1)I can’t go home now,because my task _______cleaning the windows. (2)As we all know,sea water______ much salt. 2.give in/give up (1)You must______smoking,because it is dangerous for us. (2)The young man won’t_____before any difficulty. 3. 展开更多
关键词 DANGEROUS DIFFICULTY young SMOKING cleaning HAVEN AGAIN never holds suddenly
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Future impacts of climate change on forest fire danger in northeastern China 被引量:15
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作者 TIAN Xiao-rui SHU Li-fu +2 位作者 ZHAO Feng-jun WANG Ming-yu Douglas J. McRae 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第3期437-446,共10页
Climate warming has a rapid and far-reaching impact on forest fire management in the boreal forests of China. Regional climate model outputs and the Canadian Forest Fire Weather Index (FWI) Sys- tem were used to ana... Climate warming has a rapid and far-reaching impact on forest fire management in the boreal forests of China. Regional climate model outputs and the Canadian Forest Fire Weather Index (FWI) Sys- tem were used to analyze changes to fire danger and the fire season for future periods under IPCC Special Report on Emission Scenarios (SRES) A2 and B2, and the data will guide future fire management planning. We used regional climate in China (1961 1990) as our validation data, and the period (1991–2100) was modeled under SRES A2 and B2 through the weather simulated by the regional climate model system (PRECIS). Meteorological data and fire danger were interpolated to 1 km 2 by using ANUSPLIN software. The average FWI value for future spring fire sea- sons under Scenarios A2 and B2 shows an increase over most of the region. Compared with the baseline, FWI averages of spring fire season will increase by 0.40, 0.26 and 1.32 under Scenario A2, and increase by 0.60, 1.54 and 2.56 under Scenario B2 in 2020s, 2050s and 2080s, respectively. FWI averages of autumn fire season also show an increase over most of the region. FWI values increase more for Scenario B2 than for Scenario A2 in the same periods, particularly during the 2050s and 2080s. Average future FWI values will increase under both scenarios for autumn fire season. The potential burned areas are expected to increase by 10% and 18% in spring for 2080s under Scenario A2 and B2, respectively. Fire season will be prolonged by 21 and 26 days under ScenariosA2 and B2 in 2080s respectively. 展开更多
关键词 climate change fire season forest fire danger northeastern China
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当住院变得不再顺畅患者康复之路在何方?(英文) 被引量:9
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作者 谢斌 《上海精神医学》 2012年第01X期38-40,共3页
The modern history of mental health services in China dates back to the founding of the first psychiatric hospital in Guangzhou by the missionary physician John Kerr in 1898.By the time of liberation in 1949 China’s ... The modern history of mental health services in China dates back to the founding of the first psychiatric hospital in Guangzhou by the missionary physician John Kerr in 1898.By the time of liberation in 1949 China’s population was already 500 million but there were only 10 mental health institutions,1 100 psychiatric beds and 50-60 psychiatrists in the country.Health services developed rapidly in the 1950s but by 1957 there were still only 70 psychiatric hospitals with 11 000 beds 展开更多
关键词 PSYCHIATRIC institutions FOUNDING PHYSICIAN mentally DATES GUANGZHOU DANGEROUS legal currently
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Extreme meteorological disaster effects on grain production in Jilin Province, China 被引量:11
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作者 XU Lei ZHANG Qiao +3 位作者 ZHANG Jing ZHAO Liang SUN Wei JIN Yun-xiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第2期486-496,共11页
Extreme meteorological disaster effects on grain production is mainly determined by the interaction between danger degree of hazard-induced factors and vulnerability degree of hazard-affected bodies. This paper treats... Extreme meteorological disaster effects on grain production is mainly determined by the interaction between danger degree of hazard-induced factors and vulnerability degree of hazard-affected bodies. This paper treats physical exposure, sensitivity of the response to the impact, and capabilities of disaster prevention and mitigation as a complex system for vulnerability degree of hazard-affected bodies, which included the external shocks and internal stability mechanism. Hazard-induced factors generate external shocks on grain production systems though exposure and sensitivity of hazard-affected body, and the result can be represented as affected area of grain. By quantile regression model, this paper depicts the quantitative relationship between hazard-induced factors of extreme meteorological disaster and the affected area in the tail of the distri- bution. Moreover, the model of production function have also been utilized to expound and prove the quantitative relationship between the affected area and final grain output under the internal stability mechanism of the agricultural natural resources endowment, the input factors of agricultural production, and the capacity of defending disaster. The empirical study of this paper finds that impact effects of drought disaster to grain production system presents the basic law of "diminishing marginal loss", namely, with the constant improvement of the grade of drought, marginal affected area produced by hazard-induced factors will be diminishing. Scenario simulation of extreme drought impact shows that by every 1% reduction in summer average rainfall, grain production of Jilin Province will fell 0.2549% and cut production of grain 14.69% eventually. In re- sponse to ensure China's grain security, the construction of the long-term mechanism of agricultural disaster prevention and mitigation, and the innovation of agricultural risk management tools should be also included in the agricultural policy agenda. 展开更多
关键词 extreme meteorological disaster grain production danger degree of hazard-induced factors vulnerability degreeof hazard-affected bodies Jilin Province in China
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Determining areas in an inclined coal seam floor prone to water-inrush by micro-seismic monitoring 被引量:11
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作者 Sun Jian Wang Lianguo +2 位作者 Wang Zhansheng Hou Huaqiang Shen Yifeng 《Mining Science and Technology》 EI CAS 2011年第2期165-168,共4页
The failure depth of the coal seam floor is one important consideration that must be kept in mind when mining is carried out above a confined aquifer.Determining the floor failure depth is the essential precondition f... The failure depth of the coal seam floor is one important consideration that must be kept in mind when mining is carried out above a confined aquifer.Determining the floor failure depth is the essential precondition for predicting the water-resisting ability of the floor.We have used a high-precision microseismic monitoring technique to overcome the limited amount of data available from field measurements. The failure depth of a coal seam floor,especially an inclined coal seam floor,may be more accurately estimated by monitoring the continuous,dynamic failure of the floor.The monitoring results indicate the failure depth of the coal seam floor near the workface conveyance roadway(the lower crossheading) is deeper and that the failure range is wider here compared to the coal seam floor near the return airway(the upper crossheading).The results of micro-seismic monitoring show that the dangerous area for water-inrush from the coal seam floor may be identified.This provides an important field measurement that helps ensure safe and highly efficient mining of the inclined coal seam above the confined aquifer at the Taoyuan Coal Mine. 展开更多
关键词 Inclined coal seam Water-inrush from floor Dangerous area Micro-seismic monitoring
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Immune multi-agent model using vaccine for cooperative air-defense system of systems for surface warship formation based on danger theory 被引量:9
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作者 Jun Wang Xiaozhe Zhao +2 位作者 Beiping Xu Wei Wang Zhiyong Niu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期946-953,共8页
Aiming at the problem on cooperative air-defense of surface warship formation, this paper maps the cooperative airdefense system of systems (SoS) for surface warship formation (CASoSSWF) to the biological immune s... Aiming at the problem on cooperative air-defense of surface warship formation, this paper maps the cooperative airdefense system of systems (SoS) for surface warship formation (CASoSSWF) to the biological immune system (BIS) according to the similarity of the defense mechanism and characteristics between the CASoSSWF and the BIS, and then designs the models of components and the architecture for a monitoring agent, a regulating agent, a killer agent, a pre-warning agent and a communicating agent by making use of the theories and methods of the artificial immune system, the multi-agent system (MAS), the vaccine and the danger theory (DT). Moreover a new immune multi-agent model using vaccine based on DT (IMMUVBDT) for the cooperative air-defense SoS is advanced. The immune response and immune mechanism of the CASoSSWF are analyzed. The model has a capability of memory, evolution, commendable dynamic environment adaptability and self-learning, and embodies adequately the cooperative air-defense mechanism for the CASoSSWF. Therefore it shows a novel idea for the CASoSSWF which can provide conception models for a surface warship formation operation simulation system. 展开更多
关键词 immune multi-agent model (IMM) VACCINE surface warship formation cooperative air-defense system of systems (CASoS) danger theory (DT)
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Approach to Mountain Hazards in Tibet, China 被引量:4
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作者 MADongtao TUJianjun +1 位作者 CUIPeng LURuren 《Journal of Mountain Science》 SCIE CSCD 2004年第2期143-154,共12页
Tibet is located at the southwest boundary of China. It is the main body of the Qinghai-Tibet Plateau, the highest and the youngest plateau in the world. Owing to complicated geology, Neo-tectonic movements, geomorpho... Tibet is located at the southwest boundary of China. It is the main body of the Qinghai-Tibet Plateau, the highest and the youngest plateau in the world. Owing to complicated geology, Neo-tectonic movements, geomorphology, climate and plateau environment, various mountain hazards, such as debris flow, flash flood, landslide, collapse, snow avalanche and snow drifts, are widely distributed along the Jinsha River (the upper reaches of the Yangtze River), the Nu River and the Lancang River in the east, and the Yarlungzangbo River, the Pumqu River and the Poiqu River in the south and southeast of Tibet. The distribution area of mountain hazards in Tibet is about 589,000 km2, 49.3% of its total territory. In comparison to other mountain regions in China, mountain hazards in Tibet break out unexpectedly with tremendously large scale and endanger the traffic lines, cities and towns, farmland, grassland, mountain environment, and make more dangers to the neighboring countries, such as Nepal, India, Myanmar and Bhutan. To mitigate mountain hazards, some suggestions are proposed in this paper, such as strengthening scientific research, enhancing joint studies, hazards mitigation planning, hazards warning and forecasting, controlling the most disastrous hazards and forbidding unreasonable human exploring activities in mountain areas. 展开更多
关键词 TIBET mountain hazard formation cause DANGER mitigation countermeasure
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Fuel classification and mapping from satellite imagines 被引量:3
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作者 TIAN Xiao-rui Douglas J.McRae +1 位作者 SHU Li-fu WANG Ming-yu 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期311-316,共6页
This paper summarizes the fuel type systems currently adopted by the fire danger rating systems or fire behavior prediction systems of some countries, such as Canada, the United States, Australia, Greece, and Switzerl... This paper summarizes the fuel type systems currently adopted by the fire danger rating systems or fire behavior prediction systems of some countries, such as Canada, the United States, Australia, Greece, and Switzerland. As an example, the Canadian Forest Fire Danger Rating System organizes fuel types into five major groups, with a total of 16 discrete fuel types recognized. In the United States National Fire Danger Rating System, fuel models are divided into four vegetation groups and twenty fire behavior fuel models. The Promethus System (Greece) divides fuels into 7 types, and Australia has adopted only three distinct fuel types: open grasslands, dry eucalyptus forests, and heath/shrublands. Four approaches to mapping fuels are acceptable: field reconnaissance, direct mapping methods, indirect mapping methods, and gradient modeling. Satellite remote-sensing techniques provide an alternative source of obtaining fuel data quickly, since they provide comprehensive spatial coverage and enough temporal resolution to update fuel maps in a more efficient and timely manner than traditional aerial photography or fieldwork. Satellite sensors can also provide digital information that can be easily tied into other spatial databases using Geographic Information System (GIS) analysis, which can be used as input in fire behavior and growth models. Various fuel-mapping methods from satellite remote sensing are discussed in the paper. According to the analysis of the fuel mapping techniques worldwide, this paper suggests that China should first create appropriate fuel types for its fire agencies before embarking on developing a national fire danger rating system to improve the current data situation for it's fire management programs. 展开更多
关键词 Fire behavior Fire danger Fuel type classification Fuel mapping Fuel model.
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Why is the Danger Cylinder Dangerous in the P3P Problem? 被引量:5
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作者 ZHANG Cai-Xia HU Zhan-Yi 《自动化学报》 EI CSCD 北大核心 2006年第4期504-511,共8页
The PnP problem is a widely used technique for pose determination in computer vision community,and finding out geometric conditions of multiple solutions is the ultimate and most desirable goal of the multi-solution a... The PnP problem is a widely used technique for pose determination in computer vision community,and finding out geometric conditions of multiple solutions is the ultimate and most desirable goal of the multi-solution analysis,which is also a key research issue of the problem.In this paper,we prove that given 3 control points,if the camera's optical center lies on the so-called“danger cylinder”and is enough far from the supporting plane of control points,the corresponding P3P problem must have 3 positive solutions.This result can bring some new insights into a better understanding of the multi-solution problem.For example,it is shown in the literature that the solution of the P3P problem is instable if the optical center lies on this danger cylinder,we think such occurrence of triple-solution is the primary source of this instability. 展开更多
关键词 The P3P problem the danger cylinder instability of solution
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Improved genetic algorithm freely searching for dangerous slip surface of slope 被引量:4
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作者 万文 曹平 +1 位作者 冯涛 袁海平 《Journal of Central South University of Technology》 EI 2005年第6期749-752,共4页
Based on the slice method of the non-circular slip surface for the calculation of integral stability of slope, an improved genetic algorithm was proposed, which can freely search for the most dangerous slip surface of... Based on the slice method of the non-circular slip surface for the calculation of integral stability of slope, an improved genetic algorithm was proposed, which can freely search for the most dangerous slip surface of slope and the corresponding minimum safety factor without supposing the geometric shape of the most dangerous slip surface. This improved genetic algorithm can simulate the genetic evolution process of organisms and avoid the local minimum value compared with the classical methods. The results of engineering cases show that it is a global optimal algorithm and has many advantages, such as higher efficiency and shorter time than the simple genetic algorithm. 展开更多
关键词 slice method dangerous non-circular slip surface minimum safety factor improved genetic algorithm
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Earthquake-induced collapse mechanism of two types of dangerous rock masses 被引量:3
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作者 Wang Wei Yuan Wei +1 位作者 Wang Qizhi Xue Kang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2016年第2期379-386,共8页
As the economy of China develops, an increasing number of key traffic projects have been undertaken in the west of China, where there are high, steep rock slopes. The collapse of dangerous rock masses, especially foll... As the economy of China develops, an increasing number of key traffic projects have been undertaken in the west of China, where there are high, steep rock slopes. The collapse of dangerous rock masses, especially following a strong earthquake, is one of common geological disasters known in rock slope engineering. Therefore, it is important to study the collapse mechanism of dangerous rock masses induced by an earthquake and the analysis approach of its stability. This study provides a simple and convenient method to determine the collapse mechanisms of two types of dangerous rock masses (i.e. cantilever and upright) associated with the definition and calculation of the safety factor, which is based on the flexure theory of a constant-section beam by combining with the maximum tensile-stress criterion to depict the process of crack propagation caused by seismic waves. The calculation results show that there are critical crack depths in each form of the dangerous rock masses. Once the accumulated depth of the crack growth during an earthquake exceeds the critical depth, the collapse will occur. It is also demonstrated that the crack extension amount of each step is not a constant value, and is closely associated with the current accumulated crack depth. The greater the cumulative crack depth, the more easily the crack propagates. Finally, the validity and applicability of the proposed method are verified through two actual engineering examples. 展开更多
关键词 dangerous rock mass earthquake-induced collapse cantilever beam theory safety factor high-steep rock slope
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Persistent organic pollutants control strategy in China 被引量:3
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作者 SHIYa-juan LUYong-long ZHANGHong WANGTie-yu XINGYing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期309-314,共6页
The development of Persistent Organic Pollutants(POPs) control policy in China in the context of international concerns on POPs was reviewed. The aspects of the Chinese POPs control strategies were analyzed, and compa... The development of Persistent Organic Pollutants(POPs) control policy in China in the context of international concerns on POPs was reviewed. The aspects of the Chinese POPs control strategies were analyzed, and compared with those of developed counterparts (e.g. US, EU, Japan). Currently, while the legal framework on POPs management, which complies with international guidelines has been established, it should be improved in the areas of special POPs management, risk assessment, the precautionary principle, life-cycle management and technical support capacity. The analysis of Chinese POPs policy and suggestions for strengthening the science-based decision making capacity are not only useful for Chinese decision-makers, but also a case study for developing world and make a great contribution for the global elimination of POPs to make a toxic-free future. 展开更多
关键词 Persistent Organic Pollutants(POPs) POPs policy dangerous chemicals management pesticides management Persistent Bioaccumulative Toxic Chemicals(PBTs)
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Numerical Study on the Leakage and Diffusion Characteristics of Low-Solubility and Low-Volatile Dangerous Chemicals from Ship in Inland Rivers 被引量:3
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作者 Shuifen Zhan Mingchao Wang +4 位作者 Min Wang Qianqian Shao Zefang Zhang Wenxin Jiang Xuemin Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第4期217-235,共19页
Considering the accidents of ships for dangerous chemicals transportation in inland rivers,a numerical method for the simulation of the leakage and diffusion processes of dangerous chemicals in inland rivers is propos... Considering the accidents of ships for dangerous chemicals transportation in inland rivers,a numerical method for the simulation of the leakage and diffusion processes of dangerous chemicals in inland rivers is proposed in this paper.Geographic information,such as rivers and buildings in the model,is obtained through Google Earth and structures of rivers and buildings are described by Auto CAD.In addition,the Fluent is adopted to simulate the leakage and diffusion processes of the dangerous chemicals where the standard k-εmodel is used to calculate the turbulent flow.Considering the interaction between chemicals and water,the VOF method is used to describe the leakage,drift and diffusion process of dangerous chemicals groups on the water surface.Taking a section of the Yangtze River as an example,the leakage and diffusion processes from a ship carrying 3,000 tons of low-solubility and low-volatile dangerous chemicals are studied,and the characteristics of leakage and diffusion are analyzed in detail.During the simulation,the area of the maximum group of leaked dangerous chemicals reaches up to about 1800 m2,and the number reaches up to 45.Furthermore,the influence of density,viscosity,water velocity and leakage velocity on the leakage and diffusion processes is investigated in this paper. 展开更多
关键词 Inland rivers low-solubility and low-volatile dangerous chemicals leakage and diffusion VOF.
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