Understanding hydrocarbon migration and accumulation mechanisms is one of the key scientif ic problems that should be solved for effective hydrocarbon exploration in the superimposed basins developed in northwest Chin...Understanding hydrocarbon migration and accumulation mechanisms is one of the key scientif ic problems that should be solved for effective hydrocarbon exploration in the superimposed basins developed in northwest China. The northwest striking No.1 slope break zone, which is a representative of superimposed basins in the Tarim Basin, can be divided into five parts due to the intersection of the northeast strike-slip faults. Controlled by the tectonic framework, the types and properties of reservoirs and the hydrocarbon compositions can also be divided into five parts from east to west. Anomalies of all the parameters were found on the fault intersection zone and weakened up-dip along the structural ridge away from it. Thus, it can be inferred that the intersection zone is the hydrocarbon charging position. This new conclusion differs greatly from the traditional viewpoint, which believes that the hydrocarbon migrates and accumulates along the whole plane of the No.1 slope break zone. The viewpoint is further supported by the evidence from the theory of main pathway systems, obvious improvement of the reservoir quality （2-3 orders of magnitude at the intersection zone） and the formation mechanisms of the fault intersection zone. Differential hydrocarbon migration and entrapment exists in and around the strike- slip faults. This is controlled by the internal structure of faults. It is concluded that the more complicated the fault structure is, the more significant the effects will be. If there is a deformation band, it will hinder the cross fault migration due to the common feature of two to four orders of magnitude reduction in permeability. Otherwise, hydrocarbons tend to accumulate in the up-dip structure under the control of buoyancy. Further research on the internal fault structure should be emphasized.展开更多
A statistical analysis on earthquake activity in the Kashi-Wuqia intersection area triggered by earth tide is done by Schusters test and the Permutation test on daily and monthly scales. The north-south,east-west comp...A statistical analysis on earthquake activity in the Kashi-Wuqia intersection area triggered by earth tide is done by Schusters test and the Permutation test on daily and monthly scales. The north-south,east-west component of the tidal force and tidal body stress are chosen as the tidal curve in the daily scale. The results show that most of the earthquakes occurred near the maximum 0° of the three kinds of tidal curves,the predominant tidal phases of the earthquake are- 5. 86°,6. 60° and- 15. 52°,and the frequency of the earthquakes increases with the increase of the tide; with three kinds of tidal curves( the north-south,east-west component of the tidal force and tidal body stress),the p S of Schusters test for all the earthquakes is 10. 52%,2. 40% and 2. 06%,and the p P of the Permutation test is 10. 90%,2. 40% and 2. 06%,and the results of p S and p P based on the east-west component of the tidal force and tidal body stress are below the threshold of 0. 05 that tidal triggering of earthquakes. In the monthly scale,both the p S and p P are very low( close to 0),far below the threshold of 0. 05 of tidal triggering of earthquakes,and the predominant tidal phase for earthquake triggering is- 18. 95°,close to the maximum 0°( new moon and full moon) of the earth tide in monthly scale. Regarding the statistical test result of tidal triggering of earthquakes,a preliminary explanation is given as to why the trigger effect in the east-west direction is greater than that in north-south direction.展开更多
In India, traffic flow on roads is highly mixed in nature with wide variations in the static and dynamic characteristics of vehicles. At unsignalized intersections, vehicles generally do not follow lane discipline and...In India, traffic flow on roads is highly mixed in nature with wide variations in the static and dynamic characteristics of vehicles. At unsignalized intersections, vehicles generally do not follow lane discipline and ignore the rules of priority. Drivers generally become more aggressive and tend to cross the uncontrolled intersections without considering the conflicting traffic. All these conditions cause a very complex traffic situation at unsignal- ized intersections which have a great impact on the capacity and performance of traffic intersections. A new method called additive conflict flow （ACF） method is suitable to determine the capacity of unsignalized inter- sections in non-lane-based mixed traffic conditions as prevailing in India. Occupation time is the key parameter for ACF method, which is defined as the time spent by a vehicle in the conflict area at the intersection. Data for this study were collected at two three-legged unsignalized intersections （one is uncontrolled and other one is semi- controlled） in Mangalore city, India using video-graphic technique during peak periods on three consecutive week days. The occupation time of vehicles at these intersections were studied and compared. The data on conflicting traffic volume and occupation time by each subject vehicle at the conflict area were extracted from the videos using image processing software. The subject vehicles were divided into three categories： two wheelers,cars, and auto-rickshaws. Mathematical relationships were developed to relate the occupation time of different cate- gories of vehicles with the conflicting flow of vehicles for various movements at both the intersections. It was found that occupation time increases with the increasing con- flicting traffic and observed to be higher at the uncontrolled intersection compared to the semicontrolled intersec- tion. The segregated turning movements and the presence of mini roundabout at the semicontrolled intersection reduces the conflicts of vehicular movements, which ulti- mately reduces the occupation time. The proposed methodology will be useful to determine the occupation time for various movements at unsignalized intersections. The models developed in the study can be used by practitioners and traffic engineers to estimate the capacity of unsignalized intersections in non-lane-based discipline and mixed traffic conditions.展开更多
When big trucks are running at urban road intersections,they are easy to interfere with other motor vehicles,and the turning big trucks are easy to have conflicts with non-motor vehicles and pedestrians,which will aff...When big trucks are running at urban road intersections,they are easy to interfere with other motor vehicles,and the turning big trucks are easy to have conflicts with non-motor vehicles and pedestrians,which will affect the safety of intersections.This paper first studied the intersection of trucks to the running trajectory,on this basis,through the establishment of mathematical model analysis of large truck steering conditions inside the wheel,and the influence of blind area to the driver.In the research of intersection safety design,the safety design is divided into three parts:Entrance road,internal operation and signal control.At the same time,the design method of the entrance road,the interior of the intersection and the signal control is given,which improves the safety of the truck driving at the intersection.Finally,the intersection of Jungong road and Zhoujiazui road in Yangpu district of Shanghai was selected as a case,and the optimal design of the intersection for large trucks was carried out through the investigation and analysis of actual data.The evaluation and analysis were carried out by using the multi-index matter-element model.The results show that the comprehensive safety correlation degree of the intersection is reduced to 0.42,and the safety level of is improved by one level.展开更多
Compared with conventional gas reservoirs,shale gas reservoirs are not sensitive to petrophysical properties,making it much difficult to identify this kind of reservoirs with well logging technologies.Therefore,throug...Compared with conventional gas reservoirs,shale gas reservoirs are not sensitive to petrophysical properties,making it much difficult to identify this kind of reservoirs with well logging technologies.Therefore,through a comparison of the logging curves of the Lower Silurian Longmaxi marine shale in the Jiaoshiba area,Sichuan Basin,it is found that the mud shale on conventional log curves generally features high gamma ray,high uranium,low thorium,low kalium,relative high resistivity,high interval transit time,low neutron,low density and low photoelectric absorption cross section index,while on elements logging curves,it features an increase of silicon content and a decrease of aluminum and iron content.Based on the logging response characteristics of mud shale,the logging curves most sensitive to shale,gamma ray,neutron and density logging were selected and overlaid to identify mud shale effectively.On the basis of qualitative identification,the density logging value can identify the non-organic-rich mud shale from organic-rich mud shale,because the former has a density of 2.61–2.70 g/cm^(3),while the latter has a density of less than 2.61 g/cm^(3).The identification results agree well with the results of field gas content test,TOC experiment,and gas logging,so this study can provide reference for the logging interpretation.展开更多
研究城市道路交叉口电动自行车行驶特征能够为拥堵治理和渠化改善提供量化依据。受设施环境、交通量及驾驶人行为等因素影响,电动自行车在停驻等候、启动加速和通过交叉口3个阶段呈现显著差异性特征。基于无人机航拍数据,采用Data From ...研究城市道路交叉口电动自行车行驶特征能够为拥堵治理和渠化改善提供量化依据。受设施环境、交通量及驾驶人行为等因素影响,电动自行车在停驻等候、启动加速和通过交叉口3个阶段呈现显著差异性特征。基于无人机航拍数据,采用Data From Sky交通轨迹分析软件提取基础数据,建立了包括停驻面积、机动车启动延误、电动自行车行驶速度和行驶轨迹膨胀度等关键参数的量化分析方法。以汕头市金砂路4个典型交叉口为例进行应用分析,结果表明:停驻等候阶段,停驻数量与面积呈非线性函数关系;启动加速阶段,当等候区位于机动车前方时,电动自行车停驻数量与机动车启动延误显著正相关,每10辆电动自行车造成0.6~0.9 s机动车延误;通过交叉口阶段,电动自行车85%位速度为23.5 km·h-1,且行驶轨迹膨胀度呈先增后稳的变化趋势。展开更多
Right-turn collisions at intersections are one of the most dominant crash types in suburban areas,especially at unsignalized intersections.There is,however,a lack of comprehensive research on the speed patterns of veh...Right-turn collisions at intersections are one of the most dominant crash types in suburban areas,especially at unsignalized intersections.There is,however,a lack of comprehensive research on the speed patterns of vehicles during right-turn manoeuvres and their impacts on crashes.To provide an in-depth investigation of the factors determining the safety of right-turn manoeuvres,driving behavior data were collected through an instrumented vehicle study.Using this data,binary logistic regression models were developed to identify the factors affecting the probability of vehicle-vehicle(V-V)and vehicle-pedestrian(V-P)conflicts at six suburban intersections in Babol,Iran,during right-turn stage manoeuvres.In total,1456 V-V and V-P conflicts were identified from the data analysis.The results from the logistic regression model showed that the vehicle speed,the distance between road users,as well as driver and pedestrian distractions were associated with a higher risk for V-V or V-P conflicts.To estimate the safe right-turn speeds to be selected by drivers at different stages of the right turn,i.e.,at the start,during,and end of the movement,linear regression models were developed.The results showed that participants adjust their driving behaviors the same way toward pedestrians as they do toward vehicles.The findings of this study can be leveraged for the development of a robust advanced driving assistance system,the use of which can further improve the safety performance of right-turn manoeuvres.展开更多
基金supported by the National 973 Basic Research Program (Grant No.2006CB202308)the Major National Science & Technology Program (2008ZX05008-004-012)
文摘Understanding hydrocarbon migration and accumulation mechanisms is one of the key scientif ic problems that should be solved for effective hydrocarbon exploration in the superimposed basins developed in northwest China. The northwest striking No.1 slope break zone, which is a representative of superimposed basins in the Tarim Basin, can be divided into five parts due to the intersection of the northeast strike-slip faults. Controlled by the tectonic framework, the types and properties of reservoirs and the hydrocarbon compositions can also be divided into five parts from east to west. Anomalies of all the parameters were found on the fault intersection zone and weakened up-dip along the structural ridge away from it. Thus, it can be inferred that the intersection zone is the hydrocarbon charging position. This new conclusion differs greatly from the traditional viewpoint, which believes that the hydrocarbon migrates and accumulates along the whole plane of the No.1 slope break zone. The viewpoint is further supported by the evidence from the theory of main pathway systems, obvious improvement of the reservoir quality （2-3 orders of magnitude at the intersection zone） and the formation mechanisms of the fault intersection zone. Differential hydrocarbon migration and entrapment exists in and around the strike- slip faults. This is controlled by the internal structure of faults. It is concluded that the more complicated the fault structure is, the more significant the effects will be. If there is a deformation band, it will hinder the cross fault migration due to the common feature of two to four orders of magnitude reduction in permeability. Otherwise, hydrocarbons tend to accumulate in the up-dip structure under the control of buoyancy. Further research on the internal fault structure should be emphasized.
基金sponsored by the Earthquake Situation Tracking Task of 2013(2013020119)the Fund of Earthquake Administration of Xinjiang Uygur Autonomous Region,China(201304)
文摘A statistical analysis on earthquake activity in the Kashi-Wuqia intersection area triggered by earth tide is done by Schusters test and the Permutation test on daily and monthly scales. The north-south,east-west component of the tidal force and tidal body stress are chosen as the tidal curve in the daily scale. The results show that most of the earthquakes occurred near the maximum 0° of the three kinds of tidal curves,the predominant tidal phases of the earthquake are- 5. 86°,6. 60° and- 15. 52°,and the frequency of the earthquakes increases with the increase of the tide; with three kinds of tidal curves( the north-south,east-west component of the tidal force and tidal body stress),the p S of Schusters test for all the earthquakes is 10. 52%,2. 40% and 2. 06%,and the p P of the Permutation test is 10. 90%,2. 40% and 2. 06%,and the results of p S and p P based on the east-west component of the tidal force and tidal body stress are below the threshold of 0. 05 that tidal triggering of earthquakes. In the monthly scale,both the p S and p P are very low( close to 0),far below the threshold of 0. 05 of tidal triggering of earthquakes,and the predominant tidal phase for earthquake triggering is- 18. 95°,close to the maximum 0°( new moon and full moon) of the earth tide in monthly scale. Regarding the statistical test result of tidal triggering of earthquakes,a preliminary explanation is given as to why the trigger effect in the east-west direction is greater than that in north-south direction.
文摘In India, traffic flow on roads is highly mixed in nature with wide variations in the static and dynamic characteristics of vehicles. At unsignalized intersections, vehicles generally do not follow lane discipline and ignore the rules of priority. Drivers generally become more aggressive and tend to cross the uncontrolled intersections without considering the conflicting traffic. All these conditions cause a very complex traffic situation at unsignal- ized intersections which have a great impact on the capacity and performance of traffic intersections. A new method called additive conflict flow （ACF） method is suitable to determine the capacity of unsignalized inter- sections in non-lane-based mixed traffic conditions as prevailing in India. Occupation time is the key parameter for ACF method, which is defined as the time spent by a vehicle in the conflict area at the intersection. Data for this study were collected at two three-legged unsignalized intersections （one is uncontrolled and other one is semi- controlled） in Mangalore city, India using video-graphic technique during peak periods on three consecutive week days. The occupation time of vehicles at these intersections were studied and compared. The data on conflicting traffic volume and occupation time by each subject vehicle at the conflict area were extracted from the videos using image processing software. The subject vehicles were divided into three categories： two wheelers,cars, and auto-rickshaws. Mathematical relationships were developed to relate the occupation time of different cate- gories of vehicles with the conflicting flow of vehicles for various movements at both the intersections. It was found that occupation time increases with the increasing con- flicting traffic and observed to be higher at the uncontrolled intersection compared to the semicontrolled intersec- tion. The segregated turning movements and the presence of mini roundabout at the semicontrolled intersection reduces the conflicts of vehicular movements, which ulti- mately reduces the occupation time. The proposed methodology will be useful to determine the occupation time for various movements at unsignalized intersections. The models developed in the study can be used by practitioners and traffic engineers to estimate the capacity of unsignalized intersections in non-lane-based discipline and mixed traffic conditions.
基金supported by the Ministry of education of Shanghai Philosophy and Social Science Project(Project No.2020BGL013).
文摘When big trucks are running at urban road intersections,they are easy to interfere with other motor vehicles,and the turning big trucks are easy to have conflicts with non-motor vehicles and pedestrians,which will affect the safety of intersections.This paper first studied the intersection of trucks to the running trajectory,on this basis,through the establishment of mathematical model analysis of large truck steering conditions inside the wheel,and the influence of blind area to the driver.In the research of intersection safety design,the safety design is divided into three parts:Entrance road,internal operation and signal control.At the same time,the design method of the entrance road,the interior of the intersection and the signal control is given,which improves the safety of the truck driving at the intersection.Finally,the intersection of Jungong road and Zhoujiazui road in Yangpu district of Shanghai was selected as a case,and the optimal design of the intersection for large trucks was carried out through the investigation and analysis of actual data.The evaluation and analysis were carried out by using the multi-index matter-element model.The results show that the comprehensive safety correlation degree of the intersection is reduced to 0.42,and the safety level of is improved by one level.
基金National Science and Technology Major Project“Appraisal of shale gas resources and selection of play in Shangyangzi and Yunnan-Guizhou areas”(No.14B12XQ151001).
文摘Compared with conventional gas reservoirs,shale gas reservoirs are not sensitive to petrophysical properties,making it much difficult to identify this kind of reservoirs with well logging technologies.Therefore,through a comparison of the logging curves of the Lower Silurian Longmaxi marine shale in the Jiaoshiba area,Sichuan Basin,it is found that the mud shale on conventional log curves generally features high gamma ray,high uranium,low thorium,low kalium,relative high resistivity,high interval transit time,low neutron,low density and low photoelectric absorption cross section index,while on elements logging curves,it features an increase of silicon content and a decrease of aluminum and iron content.Based on the logging response characteristics of mud shale,the logging curves most sensitive to shale,gamma ray,neutron and density logging were selected and overlaid to identify mud shale effectively.On the basis of qualitative identification,the density logging value can identify the non-organic-rich mud shale from organic-rich mud shale,because the former has a density of 2.61–2.70 g/cm^(3),while the latter has a density of less than 2.61 g/cm^(3).The identification results agree well with the results of field gas content test,TOC experiment,and gas logging,so this study can provide reference for the logging interpretation.
文摘研究城市道路交叉口电动自行车行驶特征能够为拥堵治理和渠化改善提供量化依据。受设施环境、交通量及驾驶人行为等因素影响,电动自行车在停驻等候、启动加速和通过交叉口3个阶段呈现显著差异性特征。基于无人机航拍数据,采用Data From Sky交通轨迹分析软件提取基础数据,建立了包括停驻面积、机动车启动延误、电动自行车行驶速度和行驶轨迹膨胀度等关键参数的量化分析方法。以汕头市金砂路4个典型交叉口为例进行应用分析,结果表明:停驻等候阶段,停驻数量与面积呈非线性函数关系;启动加速阶段,当等候区位于机动车前方时,电动自行车停驻数量与机动车启动延误显著正相关,每10辆电动自行车造成0.6~0.9 s机动车延误;通过交叉口阶段,电动自行车85%位速度为23.5 km·h-1,且行驶轨迹膨胀度呈先增后稳的变化趋势。
文摘Right-turn collisions at intersections are one of the most dominant crash types in suburban areas,especially at unsignalized intersections.There is,however,a lack of comprehensive research on the speed patterns of vehicles during right-turn manoeuvres and their impacts on crashes.To provide an in-depth investigation of the factors determining the safety of right-turn manoeuvres,driving behavior data were collected through an instrumented vehicle study.Using this data,binary logistic regression models were developed to identify the factors affecting the probability of vehicle-vehicle(V-V)and vehicle-pedestrian(V-P)conflicts at six suburban intersections in Babol,Iran,during right-turn stage manoeuvres.In total,1456 V-V and V-P conflicts were identified from the data analysis.The results from the logistic regression model showed that the vehicle speed,the distance between road users,as well as driver and pedestrian distractions were associated with a higher risk for V-V or V-P conflicts.To estimate the safe right-turn speeds to be selected by drivers at different stages of the right turn,i.e.,at the start,during,and end of the movement,linear regression models were developed.The results showed that participants adjust their driving behaviors the same way toward pedestrians as they do toward vehicles.The findings of this study can be leveraged for the development of a robust advanced driving assistance system,the use of which can further improve the safety performance of right-turn manoeuvres.
