Complex behavior in a selective aging simple neuron model based on small world networks is investigated. The basic elements of the model are endowed with the main features of a neuron function. The structure of the se...Complex behavior in a selective aging simple neuron model based on small world networks is investigated. The basic elements of the model are endowed with the main features of a neuron function. The structure of the selective aging neuron model is discussed. We also give some properties of the new network and find that the neuron model displays a power-law behavior. If the brain network is small world-like network, the mean avalanche size is almost the same unless the aging parameter is big enough.展开更多
To achieve the purpose of applying design patterns which are various in ldnd and constant in changing in MDA from idea and application, one way is used to solve the problem of pattern disappearance which occurs at the...To achieve the purpose of applying design patterns which are various in ldnd and constant in changing in MDA from idea and application, one way is used to solve the problem of pattern disappearance which occurs at the process of pattern instantiation, to guarantee the independence of patterns, and at the same time, to apply this process to multiple design pattems. To solve these two problons, the modeling method of design pattern traits based on meta-models is adopted, i.e., to divide the basic operations into atoms in the metamodel tier and then combine the atoms to complete design pattem units meta-models withtout business logic. After one process of conversion, the purpose of making up various pattem traits meta-model and dividing business logic and pattern logic is achieved.展开更多
Based on an integrate-and-fire mechanism, we investigate self-organized criticality of a simple neuron model on a modified BA scale-free network with aging nodes. In our model, we find that the distribution of avalanc...Based on an integrate-and-fire mechanism, we investigate self-organized criticality of a simple neuron model on a modified BA scale-free network with aging nodes. In our model, we find that the distribution of avalanche size follows power-law behavior. The critical exponent τ depends on the aging exponent α. The structures of the network with aging of nodes change with an increase of α. The different topological structures lead to different behaviors in models of integrate-and-fire neurons.展开更多
A simple model for a set of integrate-and-fire neurons based on the weighted network is introduced. By considering the neurobiological phenomenon in brain development and the difference of the synaptic strength, we co...A simple model for a set of integrate-and-fire neurons based on the weighted network is introduced. By considering the neurobiological phenomenon in brain development and the difference of the synaptic strength, we construct weighted networks develop with link additions and followed by selective edge removal. The network exhibits the small-world and scale-free properties with high network efficiency. The model displays an avalanche activity on a power-law distribution. We investigate the effect of selective edge removal and the neuron refractory period on the self-organized criticality of the system.展开更多
To describe strategies for addressing technical aspects of computational modeling of leg tissue with the finite element （FE） method, a patient＇s leg sample was selected and scanned by CT at the direction parallel t...To describe strategies for addressing technical aspects of computational modeling of leg tissue with the finite element （FE） method, a patient＇s leg sample was selected and scanned by CT at the direction parallel to the Frankfort Horizontal plane. A three-dimensional （3D） finite element model of the human leg was developed using the actual geometry of the leg skeleton and soft tissues, which were obtained from 3D reconstruction of CT images. All joints were defined as contact surfaces, which allow relative articulating movement. The major ligaments were simulated using tension-only truss elements by connecting the corresponding attachment points on the bone surfaces. The bony and ligamentous structures were embedded in a volume of soft tissues. The muscles were defined as non-linear viscoelastic material, and the skin, ligaments and tendons were defined as hyperelastic, while the bony structures were assumed to be linearly elastic. The muhilayer FEM model containing thighbone, tibia, fibula, kneecap, soft tissue was formed after meshing. Diverse forces were imposed on the FEM model. The results show that the multilayer FEM model can represent tissue deformation more accurately.展开更多
The study reveals that 10.2% of the sampled households in Nepal suffer from chronic food insecurity,i.e.,neither are they able to produce sufficient food from their farms nor earn the food security threshold income fo...The study reveals that 10.2% of the sampled households in Nepal suffer from chronic food insecurity,i.e.,neither are they able to produce sufficient food from their farms nor earn the food security threshold income for deficit months.With the highest and the lowest exponential value of coefficient obtained from binary logistic regression model,it is concluded that any program targeting occupational caste and small landholding farm category or landless will contribute significantly to reduce food-insecurity.The provision of employment opportunities for economically active age group,thus,reducing dependency ratio from 1.2 (economically active population) to 0.7 (economically active age group) can also contribute significantly to reduce food insecurity.Significant positive coefficient of family size squared shows the increase in the probability of being foodinsecure with the increase in family size.In addition,an increase in irrigation availability can contribute significantly to reduce food insecurity.A significant proportion of male-headed households and households residing in Tarai are food-secure.This justifies the need to target female-headed households and households residing in Mountain and Hill in any program aimed at resolving food insecurity.A negative and significant association of household's participation in community organizations and food insecurity fortifies the need for inclusion of vulnerable groups such as occupational caste,female-headed households,households with illiterate heads,small landholding farm category or landless,and households residing in Mountain and Hill (including some target communities in Tarai) in community organizations.Furthermore,making these communities a target of food security programs can help significantly to reduce the incidence of food insecurity.展开更多
The mesoscopic modeling developed rapidly in the past three decades is a promising tool for predicting and understanding the microstructure evolution at grain scale.In this paper,the recent development of mesoscopic m...The mesoscopic modeling developed rapidly in the past three decades is a promising tool for predicting and understanding the microstructure evolution at grain scale.In this paper,the recent development of mesoscopic modeling and its application to microstructure evolution in steels is reviewed.Firstly,some representative computational models are briefly introduced,e.g.,the phase field model,the cellular automaton model and the Monte Carlo model.Then,the emphasis is put on the application of mesoscopic modeling of the complex features of microstructure evolution,including solidification,solid-state phase transformation,recrystallization and grain growth.Finally,some issues in the present mesoscopic modeling and its perspective are discussed.展开更多
In the present study the thermal model of skin and subdermal tissues （SST） of human breast have been developed. The human breast is assumed to be spherical in shape with upper hemisphere projecting out from the trun...In the present study the thermal model of skin and subdermal tissues （SST） of human breast have been developed. The human breast is assumed to be spherical in shape with upper hemisphere projecting out from the trunk of the body and lower hemisphere is considered to be a part of the body core. The upper hemisphere represents the breast and its SST region is divided into three layers namely epidermis, dermis and subdermal tissues. The inner part of the breast represents the core/shell of the breast. The outer surface of the breast is assumed to be exposed to the environment from where the heat loss takes place by conduction, convection, radiation and evaporation. The heat transfer from core to the surface takes place by thermal conduction and blood perfusion. Also metabolic activity takes place at different rates in different SST layers of the breast. Boundary conditions have been framed on the basis of physical conditions. A finite element model has been developed for a two-dimensional steady state case.展开更多
基金National Natural Science Foundation of China under Grant No.10675060
文摘Complex behavior in a selective aging simple neuron model based on small world networks is investigated. The basic elements of the model are endowed with the main features of a neuron function. The structure of the selective aging neuron model is discussed. We also give some properties of the new network and find that the neuron model displays a power-law behavior. If the brain network is small world-like network, the mean avalanche size is almost the same unless the aging parameter is big enough.
文摘To achieve the purpose of applying design patterns which are various in ldnd and constant in changing in MDA from idea and application, one way is used to solve the problem of pattern disappearance which occurs at the process of pattern instantiation, to guarantee the independence of patterns, and at the same time, to apply this process to multiple design pattems. To solve these two problons, the modeling method of design pattern traits based on meta-models is adopted, i.e., to divide the basic operations into atoms in the metamodel tier and then combine the atoms to complete design pattem units meta-models withtout business logic. After one process of conversion, the purpose of making up various pattem traits meta-model and dividing business logic and pattern logic is achieved.
基金The project supported by National Natural Science Foundation of China under Grant No. 10675060 and the Doctoral Foundation of Ministry of Education of China
文摘Based on an integrate-and-fire mechanism, we investigate self-organized criticality of a simple neuron model on a modified BA scale-free network with aging nodes. In our model, we find that the distribution of avalanche size follows power-law behavior. The critical exponent τ depends on the aging exponent α. The structures of the network with aging of nodes change with an increase of α. The different topological structures lead to different behaviors in models of integrate-and-fire neurons.
基金Supported by National Natural Science Foundation of China under Grant No.10675060the Doctoral Foundation of Ministry of Education of China under Grant No.2002055009
文摘A simple model for a set of integrate-and-fire neurons based on the weighted network is introduced. By considering the neurobiological phenomenon in brain development and the difference of the synaptic strength, we construct weighted networks develop with link additions and followed by selective edge removal. The network exhibits the small-world and scale-free properties with high network efficiency. The model displays an avalanche activity on a power-law distribution. We investigate the effect of selective edge removal and the neuron refractory period on the self-organized criticality of the system.
基金Sponsored by the Natural Science Foundation of Heilongjiang Province of China(Grant No.200815)the Research Foundation for Talented Scholars ofHarbin (Grant No.2008RFQXS061)
文摘To describe strategies for addressing technical aspects of computational modeling of leg tissue with the finite element （FE） method, a patient＇s leg sample was selected and scanned by CT at the direction parallel to the Frankfort Horizontal plane. A three-dimensional （3D） finite element model of the human leg was developed using the actual geometry of the leg skeleton and soft tissues, which were obtained from 3D reconstruction of CT images. All joints were defined as contact surfaces, which allow relative articulating movement. The major ligaments were simulated using tension-only truss elements by connecting the corresponding attachment points on the bone surfaces. The bony and ligamentous structures were embedded in a volume of soft tissues. The muscles were defined as non-linear viscoelastic material, and the skin, ligaments and tendons were defined as hyperelastic, while the bony structures were assumed to be linearly elastic. The muhilayer FEM model containing thighbone, tibia, fibula, kneecap, soft tissue was formed after meshing. Diverse forces were imposed on the FEM model. The results show that the multilayer FEM model can represent tissue deformation more accurately.
文摘The study reveals that 10.2% of the sampled households in Nepal suffer from chronic food insecurity,i.e.,neither are they able to produce sufficient food from their farms nor earn the food security threshold income for deficit months.With the highest and the lowest exponential value of coefficient obtained from binary logistic regression model,it is concluded that any program targeting occupational caste and small landholding farm category or landless will contribute significantly to reduce food-insecurity.The provision of employment opportunities for economically active age group,thus,reducing dependency ratio from 1.2 (economically active population) to 0.7 (economically active age group) can also contribute significantly to reduce food insecurity.Significant positive coefficient of family size squared shows the increase in the probability of being foodinsecure with the increase in family size.In addition,an increase in irrigation availability can contribute significantly to reduce food insecurity.A significant proportion of male-headed households and households residing in Tarai are food-secure.This justifies the need to target female-headed households and households residing in Mountain and Hill in any program aimed at resolving food insecurity.A negative and significant association of household's participation in community organizations and food insecurity fortifies the need for inclusion of vulnerable groups such as occupational caste,female-headed households,households with illiterate heads,small landholding farm category or landless,and households residing in Mountain and Hill (including some target communities in Tarai) in community organizations.Furthermore,making these communities a target of food security programs can help significantly to reduce the incidence of food insecurity.
基金supported by the National Natural Science Foundation of China (Grant Nos. 50871109 and 51001096)
文摘The mesoscopic modeling developed rapidly in the past three decades is a promising tool for predicting and understanding the microstructure evolution at grain scale.In this paper,the recent development of mesoscopic modeling and its application to microstructure evolution in steels is reviewed.Firstly,some representative computational models are briefly introduced,e.g.,the phase field model,the cellular automaton model and the Monte Carlo model.Then,the emphasis is put on the application of mesoscopic modeling of the complex features of microstructure evolution,including solidification,solid-state phase transformation,recrystallization and grain growth.Finally,some issues in the present mesoscopic modeling and its perspective are discussed.
文摘In the present study the thermal model of skin and subdermal tissues （SST） of human breast have been developed. The human breast is assumed to be spherical in shape with upper hemisphere projecting out from the trunk of the body and lower hemisphere is considered to be a part of the body core. The upper hemisphere represents the breast and its SST region is divided into three layers namely epidermis, dermis and subdermal tissues. The inner part of the breast represents the core/shell of the breast. The outer surface of the breast is assumed to be exposed to the environment from where the heat loss takes place by conduction, convection, radiation and evaporation. The heat transfer from core to the surface takes place by thermal conduction and blood perfusion. Also metabolic activity takes place at different rates in different SST layers of the breast. Boundary conditions have been framed on the basis of physical conditions. A finite element model has been developed for a two-dimensional steady state case.
