Some researchers, running instructors, and coaches have suggested that the "optimal" footstrike pattern to improve performance and reduce running injuries is to land using a mid-or forefoot strike. Thus, it ...Some researchers, running instructors, and coaches have suggested that the "optimal" footstrike pattern to improve performance and reduce running injuries is to land using a mid-or forefoot strike. Thus, it has been recommended that runners who use a rearfoot strike would benefit by changing their footstrike although there is little scientific evidence for suggesting such a change. The rearfoot strike is clearly more prevalent. The major reasons often given for changing to a mid-or forefoot strike are(1) it is more economical;(2) there is a reduction in the impact peak and loading rate of the vertical component of the ground reaction force; and(3) there is a reduction in the risk of a running-related injuries. In this paper,we critique these 3 suggestions and provide alternate explanations that may provide contradictory evidence for altering one's footstrike pattern.We have concluded, based on examining the research literature, that changing to a mid-or forefoot strike does not improve running economy, does not eliminate an impact at the foot-ground contact, and does not reduce the risk of running-related injuries.展开更多
As one form of the energy resources, coal is becoming more and more important. Due to the particularity in coal mine production, mine accidents some time occur in countries all over the world, which result in large ca...As one form of the energy resources, coal is becoming more and more important. Due to the particularity in coal mine production, mine accidents some time occur in countries all over the world, which result in large casualties and economic losses. As equipment that can provides the miners with an emergency shelter when the coal mine accidents occur, the under ground coal mine refuge chamber is paid more and more attention by coal mine enterprises, and the application of the refuge chamber is increasingly widespread. The general functions, the classification, and the successful applications of the underground coal mine refuge chamber are illustrated first, and the research significance on the tmderground coal mine refuge chamber is stated. Following, the development status quo at home and abroad for the refuge chamber is introduced. Then, the implementation methods for the key functions of the underground coal mine refuge chamber are demonstrated. Finally, the prospect for the development of the underground coal mine refuge chamber is stated.展开更多
The Ms8.0 Wenchuan earthquake on May 12, 2008 caused heavy casualties and economic loss. According to the field investigations, the characteristics can be described as follows： The meizoseismai region with an intensi...The Ms8.0 Wenchuan earthquake on May 12, 2008 caused heavy casualties and economic loss. According to the field investigations, the characteristics can be described as follows： The meizoseismai region with an intensity of XI shows an obviously zonal distribution and suffered serious destruction from the earthquake, and the destruction perpendicular to the earthquake surface rupture decreased sharply. At the same time, the intensity X and IX regions perpendicular to the rupture are narrow and therefore their coverage area is small. The intensity on both sides of the rupture attenuates rapidly, but intensity VII and the VI regions are wide, the latter covering about 240,000 km^2. In intensity VI region, the damage area perpendicular to the rupture in the southern part is much larger than that of the northern part. Also, much new understanding about destruction types and destructive modes for all kinds of buildings, landforms and terrain is achieved in this paper.展开更多
The index of casualties is introduced for the trapped that is still alive after a destructive earthquake to indicate his (her) injury degree. In order to describe the injury-developing process controlled by three fact...The index of casualties is introduced for the trapped that is still alive after a destructive earthquake to indicate his (her) injury degree. In order to describe the injury-developing process controlled by three factors: the initial injury degree, the trap surroundings and the physique of the cornered, a function SFC (State-Function of Casualties) can be naturally constructed. Through parameter analysis from eight pieces of figures, it can be found that the trapped with weaker physique and worse initial injury degree and in more adverse trap surroundings deserves sooner rescue.展开更多
Based on economics theory,social value loss caused by vehicle involved in crashes as well as various factors influencing on it were analyzed,the corresponding mi- cro-econometrics model was theoretically given.Moreove...Based on economics theory,social value loss caused by vehicle involved in crashes as well as various factors influencing on it were analyzed,the corresponding mi- cro-econometrics model was theoretically given.Moreover,the practicability of the model, the veracity and rationality of quantification were analyzed.Based on probability theory and mathematical statistical theory,macro approach to evaluating vehicle damage in crashes was presented,and the corresponding macro-econometrics model was con- structed.In addition,the macro-econometrics model was utilized to assess economic loss from statistical data of vehicle damaged in crashes,which has shown that the model can meet the demand of quantification analysis of vehicle damage,and be applied to the evaluation of economic loss caused by crashes.The results in this paper will be of practic- al significance for scientific,comprehensive and rational evaluating socio-economic loss caused by road crashes.展开更多
An M6.5 earthquake occurred on August 3rd, 2014 in Ludian of Yunnan Province in China, causing severe casualty and economic loss. Local broadband waveform inversion with the CAP method demonstrates that the earthquake...An M6.5 earthquake occurred on August 3rd, 2014 in Ludian of Yunnan Province in China, causing severe casualty and economic loss. Local broadband waveform inversion with the CAP method demonstrates that the earthquake is a strike-slip event, with the strike along 70° and 160° for the two nodal planes respectively. However, the geological structure in the epicentral region is complicated with abundant active faults, and it is challenging to identify the seismogenic fault with the focal plane solutions due to nodal-plane ambiguity. We resolved the rupture directivity by measuring the difference between centroid location and hypocenter of the Ludian earthquake with the time shift from CAP inversion, and found that the nodal plane with the strike of 160° is the ruptured fault plane. Moreover, the rupture is found to propagate from northwest to southeast.展开更多
文摘Some researchers, running instructors, and coaches have suggested that the "optimal" footstrike pattern to improve performance and reduce running injuries is to land using a mid-or forefoot strike. Thus, it has been recommended that runners who use a rearfoot strike would benefit by changing their footstrike although there is little scientific evidence for suggesting such a change. The rearfoot strike is clearly more prevalent. The major reasons often given for changing to a mid-or forefoot strike are(1) it is more economical;(2) there is a reduction in the impact peak and loading rate of the vertical component of the ground reaction force; and(3) there is a reduction in the risk of a running-related injuries. In this paper,we critique these 3 suggestions and provide alternate explanations that may provide contradictory evidence for altering one's footstrike pattern.We have concluded, based on examining the research literature, that changing to a mid-or forefoot strike does not improve running economy, does not eliminate an impact at the foot-ground contact, and does not reduce the risk of running-related injuries.
文摘As one form of the energy resources, coal is becoming more and more important. Due to the particularity in coal mine production, mine accidents some time occur in countries all over the world, which result in large casualties and economic losses. As equipment that can provides the miners with an emergency shelter when the coal mine accidents occur, the under ground coal mine refuge chamber is paid more and more attention by coal mine enterprises, and the application of the refuge chamber is increasingly widespread. The general functions, the classification, and the successful applications of the underground coal mine refuge chamber are illustrated first, and the research significance on the tmderground coal mine refuge chamber is stated. Following, the development status quo at home and abroad for the refuge chamber is introduced. Then, the implementation methods for the key functions of the underground coal mine refuge chamber are demonstrated. Finally, the prospect for the development of the underground coal mine refuge chamber is stated.
基金sponsored by the Wenchuan M_S8.0 earthquake Emergency Response Science Investigation Program of China Earthquake Administration
文摘The Ms8.0 Wenchuan earthquake on May 12, 2008 caused heavy casualties and economic loss. According to the field investigations, the characteristics can be described as follows： The meizoseismai region with an intensity of XI shows an obviously zonal distribution and suffered serious destruction from the earthquake, and the destruction perpendicular to the earthquake surface rupture decreased sharply. At the same time, the intensity X and IX regions perpendicular to the rupture are narrow and therefore their coverage area is small. The intensity on both sides of the rupture attenuates rapidly, but intensity VII and the VI regions are wide, the latter covering about 240,000 km^2. In intensity VI region, the damage area perpendicular to the rupture in the southern part is much larger than that of the northern part. Also, much new understanding about destruction types and destructive modes for all kinds of buildings, landforms and terrain is achieved in this paper.
文摘The index of casualties is introduced for the trapped that is still alive after a destructive earthquake to indicate his (her) injury degree. In order to describe the injury-developing process controlled by three factors: the initial injury degree, the trap surroundings and the physique of the cornered, a function SFC (State-Function of Casualties) can be naturally constructed. Through parameter analysis from eight pieces of figures, it can be found that the trapped with weaker physique and worse initial injury degree and in more adverse trap surroundings deserves sooner rescue.
基金Communications Bureau of Shandong Province(2005R17)
文摘Based on economics theory,social value loss caused by vehicle involved in crashes as well as various factors influencing on it were analyzed,the corresponding mi- cro-econometrics model was theoretically given.Moreover,the practicability of the model, the veracity and rationality of quantification were analyzed.Based on probability theory and mathematical statistical theory,macro approach to evaluating vehicle damage in crashes was presented,and the corresponding macro-econometrics model was con- structed.In addition,the macro-econometrics model was utilized to assess economic loss from statistical data of vehicle damaged in crashes,which has shown that the model can meet the demand of quantification analysis of vehicle damage,and be applied to the evaluation of economic loss caused by crashes.The results in this paper will be of practic- al significance for scientific,comprehensive and rational evaluating socio-economic loss caused by road crashes.
基金supported by the National Natural Science Foundation of China(Grant No.41274069)National Basic Research Program of China(Grant No.2014CB845901)
文摘An M6.5 earthquake occurred on August 3rd, 2014 in Ludian of Yunnan Province in China, causing severe casualty and economic loss. Local broadband waveform inversion with the CAP method demonstrates that the earthquake is a strike-slip event, with the strike along 70° and 160° for the two nodal planes respectively. However, the geological structure in the epicentral region is complicated with abundant active faults, and it is challenging to identify the seismogenic fault with the focal plane solutions due to nodal-plane ambiguity. We resolved the rupture directivity by measuring the difference between centroid location and hypocenter of the Ludian earthquake with the time shift from CAP inversion, and found that the nodal plane with the strike of 160° is the ruptured fault plane. Moreover, the rupture is found to propagate from northwest to southeast.
