A methodology for studying soil polygenesis and lithological homogeneity of soil profiles is suggested. This methodology is particularly important for mountain soils, where the lithological heterogeneity of the soil p...A methodology for studying soil polygenesis and lithological homogeneity of soil profiles is suggested. This methodology is particularly important for mountain soils, where the lithological heterogeneity of the soil profiles created by denudation and accumulation processes is often observed. The methodology includes several stages： （a） the study of the lithological homogeneity/ heterogeneity of soil profiles by field and laboratory methods, （b） the stage-by-stage macro-, meso-, micro-, and submicromorphological analyses of soil profiles with additional use of the methods of neighboring sciences, and （e） the subdivision of soil features into the groups of recent and inherited （relict） features. In the latter group, the subgroups of lithorelict features inherited from the parent material and pedorelict features inherited from the previous stages of soil formation can be distinguished. Two major models of soil polygenesis are suggested. Simple models describe the soils, in which new features appear due to the changes in the environmental conditions in the course of soil evolution. Complex models describe the soils, in which such changes are combined with deposition of new portions of sediments onto the soil surface with the development of buried soil horizons （the synlithogenie pedogenesis）. The models of continuous and discontinuous synlithogenic pedogenesis can be further distinguished. It is argued that the micromorphological method applied to the studies on soil mierofabrics, microforms of soil humus, soil porosity, coatings, and various pedo- and lithorelict features yields valuable information on polygenetic soils.展开更多
Service composition is a hot and active research area in service-oriented computing which has gained great momentum. An quality of service (QoS) oriented and tree-based approach was proposed to implement service compo...Service composition is a hot and active research area in service-oriented computing which has gained great momentum. An quality of service (QoS) oriented and tree-based approach was proposed to implement service composition efficiently. Firstly, service descriptions were transformed to mapping relations which denote the association between input and output concepts. Then, the service composition problems were resolved by building mapping relation tree dynamically based on the divide and conquer method, and all mapping relation trees were combined without redundant branch to obtain the composition scheme. Finally, the optimal composition scheme was chosen based on quality of service attributes including the preference of service request. Experiment results illustrate that this method can improve the composition efficiency and reduce the searching time by increasing the number of services in repository.展开更多
Quantitative description of desorption stages of coalbed methane is an important basis to objectively understand the production of coalbed methane well,to diagnose the production state,and to optimize the management o...Quantitative description of desorption stages of coalbed methane is an important basis to objectively understand the production of coalbed methane well,to diagnose the production state,and to optimize the management of draining and collection of coalbed methane.A series of isothermal adsorption experiments were carried out with 12 anthracite samples from 6 coalbed methane wells located in the south of the Qinshui Basin,based on the results of isothermal adsorption experiments,and an analytical model was developed based on the Langmuir sorption theory.With the model,a numerical method that adopts equivalent desorption rate and its curve was established,which can be used to characterize the staged desorption of coalbed methane.According to the experimental and numerical characterizations,three key pressure points determined by the equivalent desorption rate curvature that defines pressure-declining desorption stage,have been proposed and confirmed,namely,start-up pressure,transition pressure and sensitive pressure.By using these three key pressure points,the process of coalbed methane desorption associated with isothermal adsorption experiments can be divided into four stages,i.e.,zero desorption stage,slow desorption stage,transition desorption stage,and sensitive desorption stage.According to analogy analysis,there are differences and similarities between the processes of coalbed methane desorption identified by isothermal adsorption experiments and observed in gas production.Moreover,it has been found that larger Langmuir volume and ratio of Langmuir constants are beneficial to earlier advent of steady production stage,whereas it is also possible that the declining production stage may occur ahead of schedule.展开更多
文摘A methodology for studying soil polygenesis and lithological homogeneity of soil profiles is suggested. This methodology is particularly important for mountain soils, where the lithological heterogeneity of the soil profiles created by denudation and accumulation processes is often observed. The methodology includes several stages： （a） the study of the lithological homogeneity/ heterogeneity of soil profiles by field and laboratory methods, （b） the stage-by-stage macro-, meso-, micro-, and submicromorphological analyses of soil profiles with additional use of the methods of neighboring sciences, and （e） the subdivision of soil features into the groups of recent and inherited （relict） features. In the latter group, the subgroups of lithorelict features inherited from the parent material and pedorelict features inherited from the previous stages of soil formation can be distinguished. Two major models of soil polygenesis are suggested. Simple models describe the soils, in which new features appear due to the changes in the environmental conditions in the course of soil evolution. Complex models describe the soils, in which such changes are combined with deposition of new portions of sediments onto the soil surface with the development of buried soil horizons （the synlithogenie pedogenesis）. The models of continuous and discontinuous synlithogenic pedogenesis can be further distinguished. It is argued that the micromorphological method applied to the studies on soil mierofabrics, microforms of soil humus, soil porosity, coatings, and various pedo- and lithorelict features yields valuable information on polygenetic soils.
基金Project(2007AA01Z126) supported by the National High Technology Research and Development Program of China
文摘Service composition is a hot and active research area in service-oriented computing which has gained great momentum. An quality of service (QoS) oriented and tree-based approach was proposed to implement service composition efficiently. Firstly, service descriptions were transformed to mapping relations which denote the association between input and output concepts. Then, the service composition problems were resolved by building mapping relation tree dynamically based on the divide and conquer method, and all mapping relation trees were combined without redundant branch to obtain the composition scheme. Finally, the optimal composition scheme was chosen based on quality of service attributes including the preference of service request. Experiment results illustrate that this method can improve the composition efficiency and reduce the searching time by increasing the number of services in repository.
基金supported by National KeyBasic Research Program of China (Grant No. 2009CB219605)Key Project of National Natural Science Foundation of China (Grant No.40730422)Grand Science and Technology Special Project of China(Grant No. 2011ZX05034-04)
文摘Quantitative description of desorption stages of coalbed methane is an important basis to objectively understand the production of coalbed methane well,to diagnose the production state,and to optimize the management of draining and collection of coalbed methane.A series of isothermal adsorption experiments were carried out with 12 anthracite samples from 6 coalbed methane wells located in the south of the Qinshui Basin,based on the results of isothermal adsorption experiments,and an analytical model was developed based on the Langmuir sorption theory.With the model,a numerical method that adopts equivalent desorption rate and its curve was established,which can be used to characterize the staged desorption of coalbed methane.According to the experimental and numerical characterizations,three key pressure points determined by the equivalent desorption rate curvature that defines pressure-declining desorption stage,have been proposed and confirmed,namely,start-up pressure,transition pressure and sensitive pressure.By using these three key pressure points,the process of coalbed methane desorption associated with isothermal adsorption experiments can be divided into four stages,i.e.,zero desorption stage,slow desorption stage,transition desorption stage,and sensitive desorption stage.According to analogy analysis,there are differences and similarities between the processes of coalbed methane desorption identified by isothermal adsorption experiments and observed in gas production.Moreover,it has been found that larger Langmuir volume and ratio of Langmuir constants are beneficial to earlier advent of steady production stage,whereas it is also possible that the declining production stage may occur ahead of schedule.
