The solid block model is applied to describe the motion of the pyroclastic flow under the joint action of gravity and Coulomb friction. Special attention is paid to characteristics of the pyroclastic flow generated by...The solid block model is applied to describe the motion of the pyroclastic flow under the joint action of gravity and Coulomb friction. Special attention is paid to characteristics of the pyroclastic flow generated by Montserrat volcano in likely directions. The critical friction angle of the flow propagation is evaluated empirically. Characteristic parameters of the pyroclastic flow (travel time and impact velocity) are well approximated by linear regressions. Proposed estimations of the parameters of pyroclastic flow are useful for the rough and express evaluation of its characteristics.展开更多
电介质介电响应中所蕴含的信息可以被用于探究电介质的内部微观结构以及电荷的运动特性。Debye模型描述的是没有相互作用的偶极子在黏性介质中发生的极化现象,这很难出现在实际的固体电介质中。基于Debye模型的经验修正模型如Cole-Cole...电介质介电响应中所蕴含的信息可以被用于探究电介质的内部微观结构以及电荷的运动特性。Debye模型描述的是没有相互作用的偶极子在黏性介质中发生的极化现象,这很难出现在实际的固体电介质中。基于Debye模型的经验修正模型如Cole-Cole模型、Davidson-Cole模型以及Havriliak-Negami模型中的参数没有实际的物理意义,使用经验模型分析介电响应测量结果无法获得电介质内部微观结构和电荷运行特性。由Dissado L A与Hill R M提出的具有明确物理意义、涉及微观粒子之间的相互作用的Dissado-Hill介电响应模型是一个更反映介电响应物理实质的理论模型。该文详细阐述了Dissado-Hill介电响应模型的物理意义及该模型中"簇"的概念;Dissado-Hill模型包含2个子模型:一个是用来描述偶极子主导的弛豫峰型介电响应过程的Dissado-Hill loss peak模型;一个是用来描述载流子主导的低频弥散现象的Dissado-Hill QDC模型。文中讨论了低频弥散介电响应现象与电导现象之间的异同及区分方法。结合Dissado-Hill介电响应模型和等效电路模型分析的方法,对电力系统外绝缘领域常用的高温硫化硅橡胶材料的介电响应测量结果进行了深入的分析,结果发现,高温硫化硅橡胶的介电响应中存在明显的低频弥散现象。展开更多
In this paper, antiplane response of an isosceles triangular hill to incident SH waves is studied based on the method of complex function and by using moving coordinate system. The standing wave function, which can sa...In this paper, antiplane response of an isosceles triangular hill to incident SH waves is studied based on the method of complex function and by using moving coordinate system. The standing wave function, which can satisfy the governing equation and boundary condition, is provided. Furthermore, numerical examples are presented; the influences of wave number and angle of the incident waves and the angle of the hill’s peak on ground motion are discussed.展开更多
The pattern of the subtle traps, in which oil and gas accumulated, in the buried-hill faulted zone in the Jiyang sag is very complicated, and very hard to prospect. The paper analyses the main difficulties in explorin...The pattern of the subtle traps, in which oil and gas accumulated, in the buried-hill faulted zone in the Jiyang sag is very complicated, and very hard to prospect. The paper analyses the main difficulties in exploring the complicated buried-hill faulted zone of the area from a point of geology.The typical pattern of the buried-hill zone in the Jiyang sag is studied using the forward modeling.Target-orient layout design and full 3-D seismic technology, which are useful for oil and gas exploration on the zone, are put forward. Taking the exploration for oil and gas traps on the zone as an example, certain technologies and the effect of their applications about the design for target acquisition,acquisition on a wide-azimuth, point sources and point receivers are discussed.展开更多
Because insulin released by the β-cells of pancreatic islets is the main regulator of glucose levels, the quantitative modeling of their glucose-stimulated insulin secretion is of obvious interest not only to improve...Because insulin released by the β-cells of pancreatic islets is the main regulator of glucose levels, the quantitative modeling of their glucose-stimulated insulin secretion is of obvious interest not only to improve our understanding of the processes involved, but also to allow better assessment of β -cell function in diabetic patients or islet transplant recipients as well as the development of improved artificial or bioartificial pancreas devices. We have recently developed a general, local concentrations-based multiphysics computational model of insulin secretion in avascular pancreatic islets that can be used to calculate insulin secretion for arbitrary geometries of cultured, perifused, transplanted, or encapsulated islets in response to various glucose profiles. Here, experimental results obtained from two different dynamic glucose-stimulated insulin release (GSIR) perifusion studies performed by us following standard procedures are compared to those calculated by the model. Such perifusion studies allow the quantitative assessment of insulin release kinetics under fully controllable experimental conditions of varying external concentrations of glucose, oxygen, or other compounds of interest, and can provide an informative assessment of islet quality and function. The time-profile of the insulin secretion calculated by the model was in good agree- ment with the experimental results obtained with isolated human islets. Detailed spatial distributions of glucose, oxygen, and insulin were calculated and are presented to provide a quantitative visualization of various important aspects of the insulin secretion dynamics in perifused islets.展开更多
Marius Hills is a volcanic plateau on the nearside of the Moon. It is of great interest for its high concentration of volcanic features, including domes, cones, ridges, and rilles. However, the morphological and chron...Marius Hills is a volcanic plateau on the nearside of the Moon. It is of great interest for its high concentration of volcanic features, including domes, cones, ridges, and rilles. However, the morphological and chronological characteristics of this plateau were not well studied due to the low resolution of early mission data. This study describes the detailed morphology of the volcanic features using the latest high spatial resolution images of the Terrain Camera （TC） onboard Selene-1 （10 m/pix） and Narrow Angle Camera （NAC） onboard the Lunar Reconnaissance Orbiter （LRO） （0.5 m/pix）. We report here some new structures such as skylights and remnants of lava tubes. We have divided spectrally homogenous areas with Clementine UVVIS data and did crater size frequency distribution （CSFD） measurements with Lunar Orbiter （LO） IV and TC images in every spectral unit. We first report absolute model ages of 1.10 Ga for Marius basalt 1, 1.49 Ga for Fiamsteed basalt, and 1.46 Ga for Schiaparelli Basalt. In addition, we have identified several younger lava events： they are Marius basalt 2 （814 Ma）, medium to low titanium basalt （949 Ma）, and undifferentiated medium titanium basalt （687 Ma）. Finally, we propose a mantle plume scenario for the formation of Marius Hills, which could solve the inconsistency of previous models.展开更多
The multi-analysis modeling of a complex system is the act of building a family of models which allows to cover a large spectrum of analysis methods(such as simulation,formal methods,enactment,...)that can be performe...The multi-analysis modeling of a complex system is the act of building a family of models which allows to cover a large spectrum of analysis methods(such as simulation,formal methods,enactment,...)that can be performed to derive various properties of this system.The High-Level Language for Systems Specification(HiLLS)has recently been introduced as a graphical language for discrete event simulation,with potential for other types of analysis,like enactment for rapid system prototyping.HiLLS defines an automata language that also opens the way to formal verification.This paper provides the building blocks for such a feature.That way,a unique model can be used not only to perform both simulation and enactment experiments but also to allow the logical analysis of properties without running any experiment.Therefore,it saves from the effort of building three different analysis-specific models and the need to align them semantically.展开更多
文摘The solid block model is applied to describe the motion of the pyroclastic flow under the joint action of gravity and Coulomb friction. Special attention is paid to characteristics of the pyroclastic flow generated by Montserrat volcano in likely directions. The critical friction angle of the flow propagation is evaluated empirically. Characteristic parameters of the pyroclastic flow (travel time and impact velocity) are well approximated by linear regressions. Proposed estimations of the parameters of pyroclastic flow are useful for the rough and express evaluation of its characteristics.
文摘电介质介电响应中所蕴含的信息可以被用于探究电介质的内部微观结构以及电荷的运动特性。Debye模型描述的是没有相互作用的偶极子在黏性介质中发生的极化现象,这很难出现在实际的固体电介质中。基于Debye模型的经验修正模型如Cole-Cole模型、Davidson-Cole模型以及Havriliak-Negami模型中的参数没有实际的物理意义,使用经验模型分析介电响应测量结果无法获得电介质内部微观结构和电荷运行特性。由Dissado L A与Hill R M提出的具有明确物理意义、涉及微观粒子之间的相互作用的Dissado-Hill介电响应模型是一个更反映介电响应物理实质的理论模型。该文详细阐述了Dissado-Hill介电响应模型的物理意义及该模型中"簇"的概念;Dissado-Hill模型包含2个子模型:一个是用来描述偶极子主导的弛豫峰型介电响应过程的Dissado-Hill loss peak模型;一个是用来描述载流子主导的低频弥散现象的Dissado-Hill QDC模型。文中讨论了低频弥散介电响应现象与电导现象之间的异同及区分方法。结合Dissado-Hill介电响应模型和等效电路模型分析的方法,对电力系统外绝缘领域常用的高温硫化硅橡胶材料的介电响应测量结果进行了深入的分析,结果发现,高温硫化硅橡胶的介电响应中存在明显的低频弥散现象。
文摘In this paper, antiplane response of an isosceles triangular hill to incident SH waves is studied based on the method of complex function and by using moving coordinate system. The standing wave function, which can satisfy the governing equation and boundary condition, is provided. Furthermore, numerical examples are presented; the influences of wave number and angle of the incident waves and the angle of the hill’s peak on ground motion are discussed.
文摘The pattern of the subtle traps, in which oil and gas accumulated, in the buried-hill faulted zone in the Jiyang sag is very complicated, and very hard to prospect. The paper analyses the main difficulties in exploring the complicated buried-hill faulted zone of the area from a point of geology.The typical pattern of the buried-hill zone in the Jiyang sag is studied using the forward modeling.Target-orient layout design and full 3-D seismic technology, which are useful for oil and gas exploration on the zone, are put forward. Taking the exploration for oil and gas traps on the zone as an example, certain technologies and the effect of their applications about the design for target acquisition,acquisition on a wide-azimuth, point sources and point receivers are discussed.
文摘Because insulin released by the β-cells of pancreatic islets is the main regulator of glucose levels, the quantitative modeling of their glucose-stimulated insulin secretion is of obvious interest not only to improve our understanding of the processes involved, but also to allow better assessment of β -cell function in diabetic patients or islet transplant recipients as well as the development of improved artificial or bioartificial pancreas devices. We have recently developed a general, local concentrations-based multiphysics computational model of insulin secretion in avascular pancreatic islets that can be used to calculate insulin secretion for arbitrary geometries of cultured, perifused, transplanted, or encapsulated islets in response to various glucose profiles. Here, experimental results obtained from two different dynamic glucose-stimulated insulin release (GSIR) perifusion studies performed by us following standard procedures are compared to those calculated by the model. Such perifusion studies allow the quantitative assessment of insulin release kinetics under fully controllable experimental conditions of varying external concentrations of glucose, oxygen, or other compounds of interest, and can provide an informative assessment of islet quality and function. The time-profile of the insulin secretion calculated by the model was in good agree- ment with the experimental results obtained with isolated human islets. Detailed spatial distributions of glucose, oxygen, and insulin were calculated and are presented to provide a quantitative visualization of various important aspects of the insulin secretion dynamics in perifused islets.
基金supported by the National Natural Science Foundation of China (Nos. 41072045, 41102209)the Research Fund for the Doctoral Program of Higher Education (No. 20090145110001)+1 种基金Nondestructive Analysis Technique and Best Analysis Scheme of Lunar Sample (No. TY3Q20110029)China University of Geosciences (Wuhan) GF Special Research Fund (No. CUGXGF0901)
文摘Marius Hills is a volcanic plateau on the nearside of the Moon. It is of great interest for its high concentration of volcanic features, including domes, cones, ridges, and rilles. However, the morphological and chronological characteristics of this plateau were not well studied due to the low resolution of early mission data. This study describes the detailed morphology of the volcanic features using the latest high spatial resolution images of the Terrain Camera （TC） onboard Selene-1 （10 m/pix） and Narrow Angle Camera （NAC） onboard the Lunar Reconnaissance Orbiter （LRO） （0.5 m/pix）. We report here some new structures such as skylights and remnants of lava tubes. We have divided spectrally homogenous areas with Clementine UVVIS data and did crater size frequency distribution （CSFD） measurements with Lunar Orbiter （LO） IV and TC images in every spectral unit. We first report absolute model ages of 1.10 Ga for Marius basalt 1, 1.49 Ga for Fiamsteed basalt, and 1.46 Ga for Schiaparelli Basalt. In addition, we have identified several younger lava events： they are Marius basalt 2 （814 Ma）, medium to low titanium basalt （949 Ma）, and undifferentiated medium titanium basalt （687 Ma）. Finally, we propose a mantle plume scenario for the formation of Marius Hills, which could solve the inconsistency of previous models.
基金This work has been supported by the 2017 PAMI Travel Grantthe 2019 AUST/AfDB Special Grant.
文摘The multi-analysis modeling of a complex system is the act of building a family of models which allows to cover a large spectrum of analysis methods(such as simulation,formal methods,enactment,...)that can be performed to derive various properties of this system.The High-Level Language for Systems Specification(HiLLS)has recently been introduced as a graphical language for discrete event simulation,with potential for other types of analysis,like enactment for rapid system prototyping.HiLLS defines an automata language that also opens the way to formal verification.This paper provides the building blocks for such a feature.That way,a unique model can be used not only to perform both simulation and enactment experiments but also to allow the logical analysis of properties without running any experiment.Therefore,it saves from the effort of building three different analysis-specific models and the need to align them semantically.
