Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-tempor...Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-temporal pattern of land use change. There are four physical geographical regions in Mongolian Autonomou County of Qian Gorlos of Jilin Province. Based on spatial analysis and statistical analysis, we conclude that the primary pattern of land use and the tendency of land use changes are all different in four physical geographical regions. During 1987 – 1996, the dominant land use change processes were from grassland or forest to arableland, from unused land to paddy and grassland to unused land. Though land use change is mainly affected by social and economic condition in short period, the composite characters of physical geographical elements controls land use dynamic process. The relationship between land use dynamic process and the character of physical geographical units differ in different regions. Possible human impacts on land use change are explored with application of buffer areas of series distance along main roads and radius around main settlements. A few models are built to describe the relationship between land use spatial change rates and distance to road and settlements. According to our result, the relationship with the proximity to roads was a negative liner function, with the change rate decreasing rapidly when moving away from roads. Within a distance of less 7.5km from main traffic lines, land use changes occur red more. The bulk of grassland was apt to be opened up for cultivation around the settlements and the transformation from dryland to paddy occurred within the distance of 1km away from settlements.展开更多
This study aims to develop a system and measurement method for investigating the static and dynamic pressure behavior of compression products. The self-designed measurement system, named "cloth-press" (LLY-5...This study aims to develop a system and measurement method for investigating the static and dynamic pressure behavior of compression products. The self-designed measurement system, named "cloth-press" (LLY-56B), is a direct measurement method, which is based on a rigid hemisphere with three pressure sensors distributed on its surface. The static pressure is measured at predetermined press depth, and the dynamic pressure is measured under the processing of fabric 3D deformation. The pressure distributions at the basic three sites are accepted as the measurement results. The measurement results provide much information in the field of compression fabric assessment, and the measurement system can be used in scientific research institutes and factories, contributing to optimize process parameters and quality control of compression garment.展开更多
Remote sensing technique has played an important role in land use dynamic monitoring, but as for the land use dynamic monitoring at county level, traditional remote sensing methods such as satellite imagery visual int...Remote sensing technique has played an important role in land use dynamic monitoring, but as for the land use dynamic monitoring at county level, traditional remote sensing methods such as satellite imagery visual interpretation and computer classification can not meet its demand for accuracy. The result of 1:10 000 land use investigation map has high accuracy, but this method can not be used to dynamically monitor the land use because of its big expenses, long period and difficulty in updating data. In this paper, the characteristics of physiognomy, climate and the status of land use in Dehui County are taken into consideration and a set of method, which takes use of 3S techniques and applies to Northeast China Plain, is come up with. When the land use type of a land parcel changed as a whole, the date updating can be make by changing its land type ID in the attribute table in a GIS. When the land use type of an irregular area changed, GPS receivers are used to position its border. This set of method is characteristic of high accuracy and low expenses. It gets the information of land use change timely and can be used to dynamically monitor the land use. .展开更多
In this paper, variation of wheel-rail forces in dynamic train-track interaction at high speed track is investigated. To analyze track and train dynamically, a model of standard fleet and train is provided. To model t...In this paper, variation of wheel-rail forces in dynamic train-track interaction at high speed track is investigated. To analyze track and train dynamically, a model of standard fleet and train is provided. To model the loads of track and train realistically, ADAMS / RAIL software is used. In modeling of a car by ADAMS / RAIL, an ERRI standard model of the car on a high speed track with corrugated rail （1 mm amplitude, 1 meter wavelength and total length of 5 meters） is provided. To verify the equations of dynamic load factors, offered in some codes, the software outputs and equations are compared to judge. The results of the dynamic analysis of the train shows that the equations offered in ORE manual are more applicable than those offered in the other codes.展开更多
The comers with small radii on cross sections are crucial for forming hydroformed components with polygonal sections. In this paper, warm hydroforming experiments of AZ61A magnesium alloy tubes were cartied out to stu...The comers with small radii on cross sections are crucial for forming hydroformed components with polygonal sections. In this paper, warm hydroforming experiments of AZ61A magnesium alloy tubes were cartied out to study the forming regularity of round comers by using a demonstration part with square sections. Effects of temperature on radius forming, thinning ratio distribution and microstructure were revealed and a component with relative outer corner radius of 3.0 was obtained by warm hydroforming at 240℃. The minimum thickness of the formed square section was located in the transition position between the corner and the straight wall. The thinning ratio of the round corner increased with the increase of forming temperature. Fotmability of the magnesium tube was improved by raising temperature under the effect of dynamic recrystallization at 240℃.展开更多
Measures of ionizing radiation were observed in a tower which is 20 meters above the ground relative height. They show a distinct period of 24 hours oscillation during this Februaryl 1 to April 11, 2015. It is suggest...Measures of ionizing radiation were observed in a tower which is 20 meters above the ground relative height. They show a distinct period of 24 hours oscillation during this Februaryl 1 to April 11, 2015. It is suggested that these oscillations originate from radon gas （222Rn） vented from the ground floor. One Russian specific Geiger tube with associated electronics developed at ITA was used, Monitoring of ionizing radiation from 30 keV to l0 MeV shows that the X and gamma rays up to 3.0 MeV is prevalent in the region comes from the Radon gas 222Rn that decay in 214Bi and 214pb in the energies of the gamma rays 0.269, 0.609 and 1.05 MeV respectively. Then, with this simple, portable instrument was possible to monitoring the dynamics of radon gas in the region every interval minutes.展开更多
The study aimed to evaluate soil quality using microarthopods density, diversity and soil biological quality index （QBS-ar） under different land use systems and elevation gradients. A secondary aim was to determine ...The study aimed to evaluate soil quality using microarthopods density, diversity and soil biological quality index （QBS-ar） under different land use systems and elevation gradients. A secondary aim was to determine the relationship among soil biological and physiochemical indicators. Three groups of soil microarthropods were recognized viz. （1） Collembola （38%） （2） Acarina （33%） and （3） other microarthropods （29%）. ANOVA indicated that total microarthropods densities differed significantly with land use and elevation. Population density of Acarina and other mieroarthropods were weakly significant different according to land use, while Collembola and Acarina densities showed highly significant difference with elevation. Total microarthropods, Acarina and Collembola densities were positively significantly correlated with soil organic carbon （SOC） and moisture but negatively correlated with bulk density, pH and temperature of the soil. SOC and soil moisture appeared to be good indicators of soil quality as reflected by the higher density and diversity of soil total microarthropods, Collembola, Acarina and other microarthropods group. The use of microarthropods for soil quality assessment could be effective and relatively inexpensive tool; however, further research is required to evaluate the impact of agricultural practices and elevation gradient on soil microarthropods density, diversity and species composition for the sustainable management of agro ecosystems.展开更多
Accurate detection of moving objects is an important step in stable tracking or recognition. By using a nonparametric density estimation method over a joint domain-range representation of image pixels, the correlation...Accurate detection of moving objects is an important step in stable tracking or recognition. By using a nonparametric density estimation method over a joint domain-range representation of image pixels, the correlation between neighboring pixels can be used to achieve high levels of detection accuracy in the presence of dynamic background. However, color similarity between foreground and background will cause many foreground pixels to be misclassified. In this paper, an adaptive foreground model is exploited to detect moving objects in dynamic scenes. The foreground model provides an effective description of foreground by adaptively combining the temporal persistence and spatial coherence of moving objects. Building on the advantages of MAP-MRF (the maximum a posteriori in the Markov random field) decision framework, the proposed method performs well in addressing the challenging problem of missed detection caused by similarity in color between foreground and background pixels. Experimental results on real dynamic scenes show that the proposed method is robust and efficient.展开更多
基金the auspices of the Knowledge Innovation Project of the Chinese Academy of sciences (KZCXI - Y - 02)the Key Ninth Five-Year P
文摘Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-temporal pattern of land use change. There are four physical geographical regions in Mongolian Autonomou County of Qian Gorlos of Jilin Province. Based on spatial analysis and statistical analysis, we conclude that the primary pattern of land use and the tendency of land use changes are all different in four physical geographical regions. During 1987 – 1996, the dominant land use change processes were from grassland or forest to arableland, from unused land to paddy and grassland to unused land. Though land use change is mainly affected by social and economic condition in short period, the composite characters of physical geographical elements controls land use dynamic process. The relationship between land use dynamic process and the character of physical geographical units differ in different regions. Possible human impacts on land use change are explored with application of buffer areas of series distance along main roads and radius around main settlements. A few models are built to describe the relationship between land use spatial change rates and distance to road and settlements. According to our result, the relationship with the proximity to roads was a negative liner function, with the change rate decreasing rapidly when moving away from roads. Within a distance of less 7.5km from main traffic lines, land use changes occur red more. The bulk of grassland was apt to be opened up for cultivation around the settlements and the transformation from dryland to paddy occurred within the distance of 1km away from settlements.
文摘This study aims to develop a system and measurement method for investigating the static and dynamic pressure behavior of compression products. The self-designed measurement system, named "cloth-press" (LLY-56B), is a direct measurement method, which is based on a rigid hemisphere with three pressure sensors distributed on its surface. The static pressure is measured at predetermined press depth, and the dynamic pressure is measured under the processing of fabric 3D deformation. The pressure distributions at the basic three sites are accepted as the measurement results. The measurement results provide much information in the field of compression fabric assessment, and the measurement system can be used in scientific research institutes and factories, contributing to optimize process parameters and quality control of compression garment.
基金Under the auspices of the key project of the National Ninth Five-year Plan (96-B02-01-07).
文摘Remote sensing technique has played an important role in land use dynamic monitoring, but as for the land use dynamic monitoring at county level, traditional remote sensing methods such as satellite imagery visual interpretation and computer classification can not meet its demand for accuracy. The result of 1:10 000 land use investigation map has high accuracy, but this method can not be used to dynamically monitor the land use because of its big expenses, long period and difficulty in updating data. In this paper, the characteristics of physiognomy, climate and the status of land use in Dehui County are taken into consideration and a set of method, which takes use of 3S techniques and applies to Northeast China Plain, is come up with. When the land use type of a land parcel changed as a whole, the date updating can be make by changing its land type ID in the attribute table in a GIS. When the land use type of an irregular area changed, GPS receivers are used to position its border. This set of method is characteristic of high accuracy and low expenses. It gets the information of land use change timely and can be used to dynamically monitor the land use. .
文摘In this paper, variation of wheel-rail forces in dynamic train-track interaction at high speed track is investigated. To analyze track and train dynamically, a model of standard fleet and train is provided. To model the loads of track and train realistically, ADAMS / RAIL software is used. In modeling of a car by ADAMS / RAIL, an ERRI standard model of the car on a high speed track with corrugated rail （1 mm amplitude, 1 meter wavelength and total length of 5 meters） is provided. To verify the equations of dynamic load factors, offered in some codes, the software outputs and equations are compared to judge. The results of the dynamic analysis of the train shows that the equations offered in ORE manual are more applicable than those offered in the other codes.
基金Sponsored by the National Natural Science Foundation of China for Distinguished Young Scholars(Grant No. 50525516)the National Key Technology R&D Program (Grant No. 2006BAE04B03)Program for New Century Excellent Talents in University
文摘The comers with small radii on cross sections are crucial for forming hydroformed components with polygonal sections. In this paper, warm hydroforming experiments of AZ61A magnesium alloy tubes were cartied out to study the forming regularity of round comers by using a demonstration part with square sections. Effects of temperature on radius forming, thinning ratio distribution and microstructure were revealed and a component with relative outer corner radius of 3.0 was obtained by warm hydroforming at 240℃. The minimum thickness of the formed square section was located in the transition position between the corner and the straight wall. The thinning ratio of the round corner increased with the increase of forming temperature. Fotmability of the magnesium tube was improved by raising temperature under the effect of dynamic recrystallization at 240℃.
文摘Measures of ionizing radiation were observed in a tower which is 20 meters above the ground relative height. They show a distinct period of 24 hours oscillation during this Februaryl 1 to April 11, 2015. It is suggested that these oscillations originate from radon gas （222Rn） vented from the ground floor. One Russian specific Geiger tube with associated electronics developed at ITA was used, Monitoring of ionizing radiation from 30 keV to l0 MeV shows that the X and gamma rays up to 3.0 MeV is prevalent in the region comes from the Radon gas 222Rn that decay in 214Bi and 214pb in the energies of the gamma rays 0.269, 0.609 and 1.05 MeV respectively. Then, with this simple, portable instrument was possible to monitoring the dynamics of radon gas in the region every interval minutes.
文摘The study aimed to evaluate soil quality using microarthopods density, diversity and soil biological quality index （QBS-ar） under different land use systems and elevation gradients. A secondary aim was to determine the relationship among soil biological and physiochemical indicators. Three groups of soil microarthropods were recognized viz. （1） Collembola （38%） （2） Acarina （33%） and （3） other microarthropods （29%）. ANOVA indicated that total microarthropods densities differed significantly with land use and elevation. Population density of Acarina and other mieroarthropods were weakly significant different according to land use, while Collembola and Acarina densities showed highly significant difference with elevation. Total microarthropods, Acarina and Collembola densities were positively significantly correlated with soil organic carbon （SOC） and moisture but negatively correlated with bulk density, pH and temperature of the soil. SOC and soil moisture appeared to be good indicators of soil quality as reflected by the higher density and diversity of soil total microarthropods, Collembola, Acarina and other microarthropods group. The use of microarthropods for soil quality assessment could be effective and relatively inexpensive tool; however, further research is required to evaluate the impact of agricultural practices and elevation gradient on soil microarthropods density, diversity and species composition for the sustainable management of agro ecosystems.
基金Project (Nos 60602012 and 60675023) supported by the National Natural Science Foundation of Chinathe National High-Tech Re-search and Development Program (863) of China (No 2007AA01Z 164)the Shanghai Key Laboratory Opening Plan Grant (No.06dz22103),China
文摘Accurate detection of moving objects is an important step in stable tracking or recognition. By using a nonparametric density estimation method over a joint domain-range representation of image pixels, the correlation between neighboring pixels can be used to achieve high levels of detection accuracy in the presence of dynamic background. However, color similarity between foreground and background will cause many foreground pixels to be misclassified. In this paper, an adaptive foreground model is exploited to detect moving objects in dynamic scenes. The foreground model provides an effective description of foreground by adaptively combining the temporal persistence and spatial coherence of moving objects. Building on the advantages of MAP-MRF (the maximum a posteriori in the Markov random field) decision framework, the proposed method performs well in addressing the challenging problem of missed detection caused by similarity in color between foreground and background pixels. Experimental results on real dynamic scenes show that the proposed method is robust and efficient.
