This paper reports the investigation of artificial vegetation communities on excavated slopes in a construction perturbed area of the Xiangjiaba hydroelectric power station in the Jinsha River Basin, P. R. China. Belt...This paper reports the investigation of artificial vegetation communities on excavated slopes in a construction perturbed area of the Xiangjiaba hydroelectric power station in the Jinsha River Basin, P. R. China. Belt transect and random quadrats were used in sampling and recording the vegetation of the four selected plots on the slopes. The community of each plot was characterized based on the coverage, relative importance value, richness, diversity, evenness of species derived from the survey data. Problems of these communities were identified and corresponding regulation measures were proposed to accelerate the positive succession process of the ecosystem. It is demonstrated that the artificial vegetation restoration on the excavated slope has improved the ecological environment.展开更多
A considerable amount of tunnelling has been going on in India for various projects such as hydroelectric power, irrigation, roads and railways. Most of these projects are located in Himalayas, far away from the urban...A considerable amount of tunnelling has been going on in India for various projects such as hydroelectric power, irrigation, roads and railways. Most of these projects are located in Himalayas, far away from the urban areas. Tunnelling through weak and jointed rock masses such as the one in the Himalayas is a challenging task for the planners, designers, engineers and geologists because of high overburden, thickly vegetated surface, weak, poor and fragile rocks and highly varying geology with the presence of numerous small and big shear zones, faults, etc. Due to these reasons, various tunnelling problems have been faced in the past and are still being encountered. Failures and the problems may be regarded as challenges and opportunities for generating new knowledge base and thereby increasing self-reliance in tunnelling. The experiences of Himalayan tunnelling through weak and fragile rocks covering varying and mixed geology, understanding on tunnelling in squeezing ground conditions and applicability of TBM in Himalayas are presented. It has also been highlighted that the probe holes planning, drilling and monitoring shall be followed seriously to reduce the geological surprises.展开更多
Mercury sphygmomanometer (MSM) is reliable and widely used in clinics and hospitals. The principle of Korotkoff sounds method (KSM) applied in the MSM is also a gold standard to measure blood pressure. Many efforts ha...Mercury sphygmomanometer (MSM) is reliable and widely used in clinics and hospitals. The principle of Korotkoff sounds method (KSM) applied in the MSM is also a gold standard to measure blood pressure. Many efforts have been made attempting to replace MSM, which is criticized for being not healthy and safe. In this research, an electronic blood pressure monitor, named K-sounds electronic sphygmomanometer (KESM), was designed as a substitute to MSM. The three key elements of KSM were proposed for the first time. We used appropriate electronic components to build the KESM which can fulfill the functions related to the three key elements. The KESM, which was easy to operate and free of mercury, followed the same principle as MSM. The same principle guaranteed the comparable accuracy. We took equivalence test and the results showed that the designed KESM was as accurate as the calibrated standard MSM. The designed KESM passed the certifications of SFDA and is qualified in clinics or hospitals for diagnostic purposes.展开更多
The Chaoyanggou oil field is a fractured low-permeability reservoir, where the distribution of oil and gas is controlled by the distribution and development of fractures.Based on outcrop, drilling core, thin section a...The Chaoyanggou oil field is a fractured low-permeability reservoir, where the distribution of oil and gas is controlled by the distribution and development of fractures.Based on outcrop, drilling core, thin section and log data, the development characteristics of fractures in this area are described.On this basis, the degree of fracture development was predicted by quantitative analysis of fracture strength and numerical simulation.The result shows that four groups of structural fractures, i.e., in near NS, and EW directions and in due NW and NE directions, were developed in the reservoir, with the nearly NS and EW fractures dominant, which are the along bedding decollement fractures formed by compressive folding action, while low angle shear fractures are related to thrusts.These fractures are mainly formed in the reversed tectonic stage at the end of the Mingshui formation during the Cretaceous period.The degree of fracture development is controlled by such factors as lithology, stratum thickness, faults, folds and depth.The fractures are developed with a clear zonation and are best developed in the northern zone, moderately developed towards the south and poorly developed in the middle zone.These prediction results are in good agreement with interpretation results from logs.展开更多
S-surface control has proven to be an effective means for motion control of underwater autonomous vehicles(AUV).However there are still problems maintaining steady precision of course due to the constant need to adjus...S-surface control has proven to be an effective means for motion control of underwater autonomous vehicles(AUV).However there are still problems maintaining steady precision of course due to the constant need to adjust parameters,especially where there are disturbing currents.Thus an intelligent integral was introduced to improve precision.An expert S-surface control was developed to tune the parameters on-line,based on the expert system,it provides S-surface control according to practical experience and control knowledge.To prevent control output over-compensation,a fuzzy neural network was included to adjust the production rules to the knowledge base.Experiments were conducted on an AUV simulation platform,and the results show that the expert S-surface controller performs better than an S-surface controller in environments with currents,producing good steady precision of course in a robust way.展开更多
基金Funded by the Natural Science Foundation of China (No. 50879043)the National S & T Support Program of China during the 11th Five-Year Plan Period (No. 2006BAC10B04)
文摘This paper reports the investigation of artificial vegetation communities on excavated slopes in a construction perturbed area of the Xiangjiaba hydroelectric power station in the Jinsha River Basin, P. R. China. Belt transect and random quadrats were used in sampling and recording the vegetation of the four selected plots on the slopes. The community of each plot was characterized based on the coverage, relative importance value, richness, diversity, evenness of species derived from the survey data. Problems of these communities were identified and corresponding regulation measures were proposed to accelerate the positive succession process of the ecosystem. It is demonstrated that the artificial vegetation restoration on the excavated slope has improved the ecological environment.
文摘A considerable amount of tunnelling has been going on in India for various projects such as hydroelectric power, irrigation, roads and railways. Most of these projects are located in Himalayas, far away from the urban areas. Tunnelling through weak and jointed rock masses such as the one in the Himalayas is a challenging task for the planners, designers, engineers and geologists because of high overburden, thickly vegetated surface, weak, poor and fragile rocks and highly varying geology with the presence of numerous small and big shear zones, faults, etc. Due to these reasons, various tunnelling problems have been faced in the past and are still being encountered. Failures and the problems may be regarded as challenges and opportunities for generating new knowledge base and thereby increasing self-reliance in tunnelling. The experiences of Himalayan tunnelling through weak and fragile rocks covering varying and mixed geology, understanding on tunnelling in squeezing ground conditions and applicability of TBM in Himalayas are presented. It has also been highlighted that the probe holes planning, drilling and monitoring shall be followed seriously to reduce the geological surprises.
基金Supported by the Innovation Fund Project from Ministry of Science and Technology of China (08C26214401239)
文摘Mercury sphygmomanometer (MSM) is reliable and widely used in clinics and hospitals. The principle of Korotkoff sounds method (KSM) applied in the MSM is also a gold standard to measure blood pressure. Many efforts have been made attempting to replace MSM, which is criticized for being not healthy and safe. In this research, an electronic blood pressure monitor, named K-sounds electronic sphygmomanometer (KESM), was designed as a substitute to MSM. The three key elements of KSM were proposed for the first time. We used appropriate electronic components to build the KESM which can fulfill the functions related to the three key elements. The KESM, which was easy to operate and free of mercury, followed the same principle as MSM. The same principle guaranteed the comparable accuracy. We took equivalence test and the results showed that the designed KESM was as accurate as the calibrated standard MSM. The designed KESM passed the certifications of SFDA and is qualified in clinics or hospitals for diagnostic purposes.
基金Project 40772086 supported by the National Natural Science Foundation of China
文摘The Chaoyanggou oil field is a fractured low-permeability reservoir, where the distribution of oil and gas is controlled by the distribution and development of fractures.Based on outcrop, drilling core, thin section and log data, the development characteristics of fractures in this area are described.On this basis, the degree of fracture development was predicted by quantitative analysis of fracture strength and numerical simulation.The result shows that four groups of structural fractures, i.e., in near NS, and EW directions and in due NW and NE directions, were developed in the reservoir, with the nearly NS and EW fractures dominant, which are the along bedding decollement fractures formed by compressive folding action, while low angle shear fractures are related to thrusts.These fractures are mainly formed in the reversed tectonic stage at the end of the Mingshui formation during the Cretaceous period.The degree of fracture development is controlled by such factors as lithology, stratum thickness, faults, folds and depth.The fractures are developed with a clear zonation and are best developed in the northern zone, moderately developed towards the south and poorly developed in the middle zone.These prediction results are in good agreement with interpretation results from logs.
基金Supported by the National Natural Science Foundation of China under Grant No.50579007
文摘S-surface control has proven to be an effective means for motion control of underwater autonomous vehicles(AUV).However there are still problems maintaining steady precision of course due to the constant need to adjust parameters,especially where there are disturbing currents.Thus an intelligent integral was introduced to improve precision.An expert S-surface control was developed to tune the parameters on-line,based on the expert system,it provides S-surface control according to practical experience and control knowledge.To prevent control output over-compensation,a fuzzy neural network was included to adjust the production rules to the knowledge base.Experiments were conducted on an AUV simulation platform,and the results show that the expert S-surface controller performs better than an S-surface controller in environments with currents,producing good steady precision of course in a robust way.