The economic benefits of transport infrastructure investment have been widely accepted.However,the varying influence of road transport development across vertical space has rarely been discussed.Taking Sichuan provinc...The economic benefits of transport infrastructure investment have been widely accepted.However,the varying influence of road transport development across vertical space has rarely been discussed.Taking Sichuan province in China as case study area where the landform is diverse and complex,administrative counties were categorized into 4 main types:plain counties,hill counties,mountain counties,and plateau counties.Using statistical data during 2006-2014,theperformanceofeconomic development and transport construction level in the four types of counties are discussed.Subsequently,the heterogeneous effect of each grade road on economy was calculated by local regression model(GWR).The results indicate that plain counties largely surpassed the other geomorphic counties in economic development level,while the gradient gap among them was on the decline.Similarly,distribution of transport infrastructure presented a decreasing trend from the low plain counties to high plateau counties.Regional imbalances were mainly reflected in the County road and Village road.Regarding the changes of regional gaps,National&Provincial roads and County roads were constantly expanding,whereas the disparity of Village road was slowly narrowing over time.Particularly noteworthy was the non-stationary economic influence of traffic factors across vertical gradients.On average,National&Provincial roads generated higher benefits in the high elevation regions than the lowlands.In contrast,County road and Village road were found to be more effective in promoting economic development in plains.With regard to local estimates of traffic factors,coefficients in mountain counties exhibited larger fluctuation ranges than other geomorphic units.The conclusions provide a basis for government decisionmaking in a more reasonable construction arrangement of road facilities and sustainable economic development.展开更多
Based on statistical analysis on morphological data of nebkhas surveyed in the Hotan River Basin,Xinjiang, the changing regularity and characters of nebkhas’ morphology in different development stageshave been discus...Based on statistical analysis on morphological data of nebkhas surveyed in the Hotan River Basin,Xinjiang, the changing regularity and characters of nebkhas’ morphology in different development stageshave been discussed. Results indicate that there exist better correlation among length, width and altitudeof all kinds of nebkhas, but there are certain various shape characters in different nebkhas and the sametype of nebkhas in differential development stages. On account of analysis on mathematical imitation ofnebkhas’ shape characters, regional ecological environmental and aeolian characters, the development ofthe nebkha can be divided into a growing stage, a stabilizing stage and a declining stage.展开更多
This paper deals with linear refraction-difractional and nonlinear dispersion mathematical models for simulation of low-frequency waves in port areas of various configurations. The phenomenon of resonance can be obser...This paper deals with linear refraction-difractional and nonlinear dispersion mathematical models for simulation of low-frequency waves in port areas of various configurations. The phenomenon of resonance can be observed in multiple places and pose a significant danger for ships and constructions. Generally, if the bottom relief is non-uniform and if inner/outer boundaries of protected areas are configurated in a complex way, the problem can be solved only by numerical methods. It presents the calculation results for the amplitude of infragravity waves at resonance frequencies. The paper highlights the solutions for diminishing the amplitude of resonance water fluctuations in port areas. In particular, it is noted that if a number of certain conditions is provided outside the protected area, it is possible to diminish substantially the height of infragravity waves inside the area. The validity of such an assumption is confirmed by calculations.展开更多
Since 2007 the CSES is the only source that every year has provided estimates of Cambodian demographic statistics such as population and household sizes by geographical region, sex, marital status and ethnicity. This ...Since 2007 the CSES is the only source that every year has provided estimates of Cambodian demographic statistics such as population and household sizes by geographical region, sex, marital status and ethnicity. This ＂work＂ describes the methodology used to make the estimates consistent with Census projections taking into account change in household sizes. The methods are based on assumptions and they will adjust the weights of the survey. The assumptions need to be evaluated continuously and this presentation is the first documentation and evaluation. Using time series of some key statistics, the work also presents and discusses the demographic development in Cambodia. A future decision if the methodology in the CSES has to be completely changed or just updated must be made when the Inter-censual result from 2013 are available.展开更多
Standard schedules for equine influenza vaccinations have been published in Finland. However, no knowledge about the actual number of vaccinations has been available. Based on previous preliminary studies in slaughter...Standard schedules for equine influenza vaccinations have been published in Finland. However, no knowledge about the actual number of vaccinations has been available. Based on previous preliminary studies in slaughterhouses and among horse owners, it was suspected that vaccination recommendations are not always followed. The aims were to investigate vaccination status against equine influenza among Finnish racehorses in regional competitions. Vaccination status was investigated： （1） by utilizing database vaccination information of show jumping and dressage horses and （2） by carrying out a survey among horse industry experts. A total of 400 horses were selected at the beginning of the Finnish competition season in 2012 and five experts （key persons） were invited to a repeated survey implemented by Delphi techniques. Overall, 50%-100% of horses were properly vaccinated depending on the source available. Thirty-four percent （34%） of the horses had the competition license but no vaccination markings in the database. Differences between types of competition （show jumping and dressage） and between Southern and Northern parts of Finland were found. Vaccinations of show jumping horses were registered more often than vaccinations of dressage horses. Ninety percent （90%） of unvaccinated horses in the database were eight years or older. It can be concluded that equine influenza vaccination registry coverage among racehorses in Finland is incomplete. This poses a risk of misunderstanding, and the growing responsibility of competition organizers.展开更多
An MRPC prototype for the future CBM-TOF inner area has been developed.The counter assembled with low resistive glass consists of 10×0.22 mm gas gaps and 2×8 readout pads.The size of each pad is 20 mm×2...An MRPC prototype for the future CBM-TOF inner area has been developed.The counter assembled with low resistive glass consists of 10×0.22 mm gas gaps and 2×8 readout pads.The size of each pad is 20 mm×20 mm with an interval of 2 mm between pads.The signals of the counter are collected by 4 eight-pin connectors.Preliminary tests performed with cosmic-rays showed an efficiency over 98%and a time resolution around 60 ps.The measured crosstalk,dark current and dark rate were at a very low levels.Results under uniform irradiation performed at JINR with high energy deuteron showed a time resolution of40–50 ps and over 98%efficiency at a low flux rate,meanwhile at a flux up to 70 kHz/cm2,93%efficiency and 77 ps time resolution still remained.These excellent performances call fully meet the demand of CBM-TOF inner wall.展开更多
The expansion of the estimated stability region plays an important role in the stability analysis of nonlinear systems.However,current literatures have not provided a complete mathematical description for this problem...The expansion of the estimated stability region plays an important role in the stability analysis of nonlinear systems.However,current literatures have not provided a complete mathematical description for this problem.This paper reveals that essentially the enlargement or the compression of the estimated stability region results directly from the diffeomorphism map,which is induced by the flow contained in the stability region.By proving that any integration algorithm with an order higher than one can approximately trace the flow of the system,a generalized methodology is proposed to construct various algorithms to realize the enlargement or the compression of the estimated stability region.With this methodology,two new algorithms based on symbolic calculation are suggested to reduce the computational burden.Furthermore,this methodology is applied to construct a scalable numerical algorithm to calculate the critical clearing time(CCT) of the power system for given faults.Tests on the IEEE 10-machine 39-bus system show that the computational results coincide well with the step-by-step simulation with high accuracy.展开更多
It is presented in this paper that the new design and its analysis of finite difference domain decomposition algorithms for the two-dimensional heat equation, and the numerical results have shown the stability and acc...It is presented in this paper that the new design and its analysis of finite difference domain decomposition algorithms for the two-dimensional heat equation, and the numerical results have shown the stability and accuracy of the algorithms, where SauFyev asymmetric schemes have been used at the interface points. The Algorithm II in this paper has further extended those developed by Dawson and the others, Zhang and Shen.展开更多
Selectivity estimation is crucial for query optimizers choosing an optimal spatial execution plan in a spatial database management system.This paper presents an Annular Bucket spatial histogram(AB histogram)that can e...Selectivity estimation is crucial for query optimizers choosing an optimal spatial execution plan in a spatial database management system.This paper presents an Annular Bucket spatial histogram(AB histogram)that can estimate the selectivity in finer spatial selection and spatial join operations even when the spatial query has more operators or more joins.The AB histogram is represented as a set of bucket-range,bucket-count value pairs.The bucket-range often covers an annular region like a sin-gle-cell-sized photo frame.The bucket-count is the number of objects whose Minimum Bounding Rectangles(MBRs)fall between outer rectangle and inner rectangle of the bucket-range.Assuming that all MBRs in each a bucket distribute evenly,for every buck-et,we can obtain serial probabilities that satisfy a certain spatial selection or join conditions from the operations' semantics and the spatial relations between every bucket-range and query ranges.Thus,according to some probability theories,spatial selection or join selectivity can be estimated by the every bucket-count and its probabilities.This paper also shows a way to generate an updated AB histogram from an original AB histogram and those probabilities.Our tests show that the AB histogram not only supports the selectivity estimation of spatial selection or spatial join with "disjoint","intersect","within","contains",and "overlap" operators but also provides an approach to generate a reliable updated histogram whose spatial distribution is close to the distribution of ac-tual query result.展开更多
基金supported by the National Natural Science Foundation of China (Grants No. 41571523 and 41661144038)the National Basic Research Program of China (973 Program) (Grant No. 2013CBA01808)the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (Grant No. 2014BAC05B01)
文摘The economic benefits of transport infrastructure investment have been widely accepted.However,the varying influence of road transport development across vertical space has rarely been discussed.Taking Sichuan province in China as case study area where the landform is diverse and complex,administrative counties were categorized into 4 main types:plain counties,hill counties,mountain counties,and plateau counties.Using statistical data during 2006-2014,theperformanceofeconomic development and transport construction level in the four types of counties are discussed.Subsequently,the heterogeneous effect of each grade road on economy was calculated by local regression model(GWR).The results indicate that plain counties largely surpassed the other geomorphic counties in economic development level,while the gradient gap among them was on the decline.Similarly,distribution of transport infrastructure presented a decreasing trend from the low plain counties to high plateau counties.Regional imbalances were mainly reflected in the County road and Village road.Regarding the changes of regional gaps,National&Provincial roads and County roads were constantly expanding,whereas the disparity of Village road was slowly narrowing over time.Particularly noteworthy was the non-stationary economic influence of traffic factors across vertical gradients.On average,National&Provincial roads generated higher benefits in the high elevation regions than the lowlands.In contrast,County road and Village road were found to be more effective in promoting economic development in plains.With regard to local estimates of traffic factors,coefficients in mountain counties exhibited larger fluctuation ranges than other geomorphic units.The conclusions provide a basis for government decisionmaking in a more reasonable construction arrangement of road facilities and sustainable economic development.
基金Supported by the National Natural Science of China (No.40461002,40861008)the Key Project of the Ministry of Education (No. 209141 )Doctoral Scientific and Technological Initial Funds of Xinjiang Normal University.
文摘Based on statistical analysis on morphological data of nebkhas surveyed in the Hotan River Basin,Xinjiang, the changing regularity and characters of nebkhas’ morphology in different development stageshave been discussed. Results indicate that there exist better correlation among length, width and altitudeof all kinds of nebkhas, but there are certain various shape characters in different nebkhas and the sametype of nebkhas in differential development stages. On account of analysis on mathematical imitation ofnebkhas’ shape characters, regional ecological environmental and aeolian characters, the development ofthe nebkha can be divided into a growing stage, a stabilizing stage and a declining stage.
文摘This paper deals with linear refraction-difractional and nonlinear dispersion mathematical models for simulation of low-frequency waves in port areas of various configurations. The phenomenon of resonance can be observed in multiple places and pose a significant danger for ships and constructions. Generally, if the bottom relief is non-uniform and if inner/outer boundaries of protected areas are configurated in a complex way, the problem can be solved only by numerical methods. It presents the calculation results for the amplitude of infragravity waves at resonance frequencies. The paper highlights the solutions for diminishing the amplitude of resonance water fluctuations in port areas. In particular, it is noted that if a number of certain conditions is provided outside the protected area, it is possible to diminish substantially the height of infragravity waves inside the area. The validity of such an assumption is confirmed by calculations.
文摘Since 2007 the CSES is the only source that every year has provided estimates of Cambodian demographic statistics such as population and household sizes by geographical region, sex, marital status and ethnicity. This ＂work＂ describes the methodology used to make the estimates consistent with Census projections taking into account change in household sizes. The methods are based on assumptions and they will adjust the weights of the survey. The assumptions need to be evaluated continuously and this presentation is the first documentation and evaluation. Using time series of some key statistics, the work also presents and discusses the demographic development in Cambodia. A future decision if the methodology in the CSES has to be completely changed or just updated must be made when the Inter-censual result from 2013 are available.
文摘Standard schedules for equine influenza vaccinations have been published in Finland. However, no knowledge about the actual number of vaccinations has been available. Based on previous preliminary studies in slaughterhouses and among horse owners, it was suspected that vaccination recommendations are not always followed. The aims were to investigate vaccination status against equine influenza among Finnish racehorses in regional competitions. Vaccination status was investigated： （1） by utilizing database vaccination information of show jumping and dressage horses and （2） by carrying out a survey among horse industry experts. A total of 400 horses were selected at the beginning of the Finnish competition season in 2012 and five experts （key persons） were invited to a repeated survey implemented by Delphi techniques. Overall, 50%-100% of horses were properly vaccinated depending on the source available. Thirty-four percent （34%） of the horses had the competition license but no vaccination markings in the database. Differences between types of competition （show jumping and dressage） and between Southern and Northern parts of Finland were found. Vaccinations of show jumping horses were registered more often than vaccinations of dressage horses. Ninety percent （90%） of unvaccinated horses in the database were eight years or older. It can be concluded that equine influenza vaccination registry coverage among racehorses in Finland is incomplete. This poses a risk of misunderstanding, and the growing responsibility of competition organizers.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11020101059, 10775082, and 11275108)
文摘An MRPC prototype for the future CBM-TOF inner area has been developed.The counter assembled with low resistive glass consists of 10×0.22 mm gas gaps and 2×8 readout pads.The size of each pad is 20 mm×20 mm with an interval of 2 mm between pads.The signals of the counter are collected by 4 eight-pin connectors.Preliminary tests performed with cosmic-rays showed an efficiency over 98%and a time resolution around 60 ps.The measured crosstalk,dark current and dark rate were at a very low levels.Results under uniform irradiation performed at JINR with high energy deuteron showed a time resolution of40–50 ps and over 98%efficiency at a low flux rate,meanwhile at a flux up to 70 kHz/cm2,93%efficiency and 77 ps time resolution still remained.These excellent performances call fully meet the demand of CBM-TOF inner wall.
基金supported by the National Natural Science Foundation (Grant Nos 50525721, 50595411)
文摘The expansion of the estimated stability region plays an important role in the stability analysis of nonlinear systems.However,current literatures have not provided a complete mathematical description for this problem.This paper reveals that essentially the enlargement or the compression of the estimated stability region results directly from the diffeomorphism map,which is induced by the flow contained in the stability region.By proving that any integration algorithm with an order higher than one can approximately trace the flow of the system,a generalized methodology is proposed to construct various algorithms to realize the enlargement or the compression of the estimated stability region.With this methodology,two new algorithms based on symbolic calculation are suggested to reduce the computational burden.Furthermore,this methodology is applied to construct a scalable numerical algorithm to calculate the critical clearing time(CCT) of the power system for given faults.Tests on the IEEE 10-machine 39-bus system show that the computational results coincide well with the step-by-step simulation with high accuracy.
基金supported by Natural Science Foundation of China under Grant Nos.10671060 and 10871061the Youth Foundation of Hunan Education Bureau under Grant No.06B037+1 种基金the Natural Science Foundation of Hunan Province under Grant No.09JJ6015the Construct Program of the Key Discipline in Hunan Province
文摘It is presented in this paper that the new design and its analysis of finite difference domain decomposition algorithms for the two-dimensional heat equation, and the numerical results have shown the stability and accuracy of the algorithms, where SauFyev asymmetric schemes have been used at the interface points. The Algorithm II in this paper has further extended those developed by Dawson and the others, Zhang and Shen.
基金Supported by the Innovation Project of IGSNRR (No. O9V90220ZZ)the Research Plan of LREIS (O88RA700KA),CAS
文摘Selectivity estimation is crucial for query optimizers choosing an optimal spatial execution plan in a spatial database management system.This paper presents an Annular Bucket spatial histogram(AB histogram)that can estimate the selectivity in finer spatial selection and spatial join operations even when the spatial query has more operators or more joins.The AB histogram is represented as a set of bucket-range,bucket-count value pairs.The bucket-range often covers an annular region like a sin-gle-cell-sized photo frame.The bucket-count is the number of objects whose Minimum Bounding Rectangles(MBRs)fall between outer rectangle and inner rectangle of the bucket-range.Assuming that all MBRs in each a bucket distribute evenly,for every buck-et,we can obtain serial probabilities that satisfy a certain spatial selection or join conditions from the operations' semantics and the spatial relations between every bucket-range and query ranges.Thus,according to some probability theories,spatial selection or join selectivity can be estimated by the every bucket-count and its probabilities.This paper also shows a way to generate an updated AB histogram from an original AB histogram and those probabilities.Our tests show that the AB histogram not only supports the selectivity estimation of spatial selection or spatial join with "disjoint","intersect","within","contains",and "overlap" operators but also provides an approach to generate a reliable updated histogram whose spatial distribution is close to the distribution of ac-tual query result.
