1996年，美国科学哲学家弗兰克·萨勒维出版了《生就反叛》(Born to Rebel)一书，在西方科学哲学、科学社会学和科学史学界引起震动。该书提出“生育顺序”（birth order ）概念，认为生育顺序是科学革命时期影响理论选择的最重要...1996年，美国科学哲学家弗兰克·萨勒维出版了《生就反叛》(Born to Rebel)一书，在西方科学哲学、科学社会学和科学史学界引起震动。该书提出“生育顺序”（birth order ）概念，认为生育顺序是科学革命时期影响理论选择的最重要的因素。以M·所罗门为代表的一些学者对萨勒维提出责难，认为：1、生育顺序作用的解释能力是有限的；2、在理论选择过程中，生育顺序作用不能取代科学的理性的作用；3、以生育顺序作用为基础的进化认识论是片面的。展开更多
The development of open-pit mines can adversely affect and even damage existing access tunnels. To ensure the safety and serviceability of them, it is essential to know potential adverse effects of the mining sequence...The development of open-pit mines can adversely affect and even damage existing access tunnels. To ensure the safety and serviceability of them, it is essential to know potential adverse effects of the mining sequence on existing tunnels such as displacements of the lining and additional loads on the lining. In this paper, three-dimensional numerical parametric study is performed to explore this complex interaction. This study investigates the effects of different parameters that may affect the tunnel response. These parameters are： excavation sequence method, horizontal/vertical stress ratio, slope angle, and tunnel diameter. This study shows that the mining sequence affects the stability of the tunnels. The open-pit mining activities lead to both higher axial forces in rock bolts and normal forces and bending moments in the lining. The results of the analysis also demonstrate that the mining sequence causes tunnel heave and significant tensile forces in the lining. Based on the study in this paper a better understanding of the interaction between oDen-oit minin~ seouence and tunnels will he ohtained展开更多
Conversation analysis （CA） is an integral part of the study of language in communication, in which preference organization is an important topic for pragmatic research. This paper makes a study of preferred and disp...Conversation analysis （CA） is an integral part of the study of language in communication, in which preference organization is an important topic for pragmatic research. This paper makes a study of preferred and dispreferred second turns in naturally occurring interactions to show structurally expected or unexpected responses from the second parts of the adjacent pairs. The study is based on the analysis of examples of people＇s actual conversations. It is concluded that in actual conversations, the speaker may make a preferred or dispreferred answer in either marked or unmarked form according to the speaker＇s intention and conversation circumstances.展开更多
The scope and aim of this work is to describe the two-body interaction mediated by a particle （either the scalar or the gauge boson） within the light-front formulation. To do this, first of all we point out the impo...The scope and aim of this work is to describe the two-body interaction mediated by a particle （either the scalar or the gauge boson） within the light-front formulation. To do this, first of all we point out the importance of propagators and Green functions in Quantum Mechanics. Then we project the covariant quantum propagator onto the light front time to get the propagator for scalar particles in these coordinates. This operator propagates the wave function from x＋ = 0 to x＋ 〉 0. It corresponds to the definition of the time ordering operation in the light front time x＋. We calculate the light-front Green＇s function for 2 interacting bosons propagating forward in x＋. We also show how to write down the light front Green＇s function from the Feynman propagator and finally make a generalization to N bosons.展开更多
文摘1996年，美国科学哲学家弗兰克·萨勒维出版了《生就反叛》(Born to Rebel)一书，在西方科学哲学、科学社会学和科学史学界引起震动。该书提出“生育顺序”（birth order ）概念，认为生育顺序是科学革命时期影响理论选择的最重要的因素。以M·所罗门为代表的一些学者对萨勒维提出责难，认为：1、生育顺序作用的解释能力是有限的；2、在理论选择过程中，生育顺序作用不能取代科学的理性的作用；3、以生育顺序作用为基础的进化认识论是片面的。
文摘The development of open-pit mines can adversely affect and even damage existing access tunnels. To ensure the safety and serviceability of them, it is essential to know potential adverse effects of the mining sequence on existing tunnels such as displacements of the lining and additional loads on the lining. In this paper, three-dimensional numerical parametric study is performed to explore this complex interaction. This study investigates the effects of different parameters that may affect the tunnel response. These parameters are： excavation sequence method, horizontal/vertical stress ratio, slope angle, and tunnel diameter. This study shows that the mining sequence affects the stability of the tunnels. The open-pit mining activities lead to both higher axial forces in rock bolts and normal forces and bending moments in the lining. The results of the analysis also demonstrate that the mining sequence causes tunnel heave and significant tensile forces in the lining. Based on the study in this paper a better understanding of the interaction between oDen-oit minin~ seouence and tunnels will he ohtained
文摘Conversation analysis （CA） is an integral part of the study of language in communication, in which preference organization is an important topic for pragmatic research. This paper makes a study of preferred and dispreferred second turns in naturally occurring interactions to show structurally expected or unexpected responses from the second parts of the adjacent pairs. The study is based on the analysis of examples of people＇s actual conversations. It is concluded that in actual conversations, the speaker may make a preferred or dispreferred answer in either marked or unmarked form according to the speaker＇s intention and conversation circumstances.
文摘The scope and aim of this work is to describe the two-body interaction mediated by a particle （either the scalar or the gauge boson） within the light-front formulation. To do this, first of all we point out the importance of propagators and Green functions in Quantum Mechanics. Then we project the covariant quantum propagator onto the light front time to get the propagator for scalar particles in these coordinates. This operator propagates the wave function from x＋ = 0 to x＋ 〉 0. It corresponds to the definition of the time ordering operation in the light front time x＋. We calculate the light-front Green＇s function for 2 interacting bosons propagating forward in x＋. We also show how to write down the light front Green＇s function from the Feynman propagator and finally make a generalization to N bosons.
