Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal re...Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal representation,design process model and design algorithm.The implementing scheme and formal description of feature taxonomy,feature operator,feature model validation and feature transformation are given in the paper.The feature based design process model suited for either sequencial or concurrent engineering is proposed and its application to product structural design and process plan design is presented. Some general design algorithms for developing feature based design system are also addressed.The proposed scheme provides a formal methodology elementary for feature based design system development and operation in a structural way.展开更多
Based on the definition of a logic structure feature to relate logically functional requirements to geometric representation independent upon detailed geometric representation, this paper presents an idea of logical s...Based on the definition of a logic structure feature to relate logically functional requirements to geometric representation independent upon detailed geometric representation, this paper presents an idea of logical structure modeling for computer aided conceptual design and makes attempt to establish a representation formalism of logic structure modeling. The definition and representation of logical structure feature are given and an assembly module definition for supporting top down conceptual design is also proposed. The proposed scheme contributes to several aspects of conceptual design research, especially to provide elementarily a formal methodology for computer aided conceptual design system development and operation.展开更多
Minjian has become an important concept in recent scholarly research. It is widely used by scholars to indicate specific social and cultural spaces existing beyond the control of state power, therefore, minjian social...Minjian has become an important concept in recent scholarly research. It is widely used by scholars to indicate specific social and cultural spaces existing beyond the control of state power, therefore, minjian social-cultural spaces are more often than not marginal and peripheral. In the field of performing arts, minjian theatre refers to performances produced by private theatre companies as opposed to state-run groups. These private companies or grass-root groups, without the interference of the government, produce artistic expressions that reflect current social reality to a certain extent. For a long time, the study of minjian theatre has been framed as forms of resistance against the ideology propagated by state-run theatres. Based on this paradigm, this paper, through the case analysis of Shanghai minjian theatre companies, attempts to illuminate the production mechanism and developmental process of minjian theatres. In so dong, this paper will explore the aesthetic and social-political values of minjian theatres.展开更多
X-ray photoelectron spectroscopy (XPS) and automatic titrimeter were nsed to study the relation be-tween pH and the transformation of the coordinate forms of P on goethite surfaces. The results showed thatfor a given ...X-ray photoelectron spectroscopy (XPS) and automatic titrimeter were nsed to study the relation be-tween pH and the transformation of the coordinate forms of P on goethite surfaces. The results showed thatfor a given P concentration, increasing the pH of suspension could cause a fast transformation of monodentatecomplexes of phosphate ions on goethite surfaces to binuclear ones. When lowering the PH, additional adsorp-tion of P occurred and the binuclear complexes reverted slowly to the monodentate ones. The dissociationand association of protons of the sorbed P caused by PH changes was considered to be a major reason lewtingto the transformation of the coordinate forms of P on the surfaces. The stability of binuclear surface complexof P was greater than that of monodentate complex. The possible reactions on the interface of goethite andsolutions with pH changes, and the reasons causing the different stabilities of the two coordinate P complexesare discussed in the paper.展开更多
As a new form of artistic expression, film has gone through a history of more than 100 years in China. Focusing on the aesthetic taste of the underclass, popular literary tradition, which highlights appreciation habit...As a new form of artistic expression, film has gone through a history of more than 100 years in China. Focusing on the aesthetic taste of the underclass, popular literary tradition, which highlights appreciation habits of the citizen stratum, is the quintessence of Chinese traditional culture. Breaking through the mode of Western films, the early Chinese film, referring to artistic elements in story-telling script, fiction, and drama in Song and Yuan Dynasties, has created new film genres of ＂unofficial historical film＂ and martial-art film which are positive results of the localization of early Chinese films. Though the unofficial historical film failed in adapting the theme of popular literature, its groundbreaking significance is still worth approving展开更多
文摘Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal representation,design process model and design algorithm.The implementing scheme and formal description of feature taxonomy,feature operator,feature model validation and feature transformation are given in the paper.The feature based design process model suited for either sequencial or concurrent engineering is proposed and its application to product structural design and process plan design is presented. Some general design algorithms for developing feature based design system are also addressed.The proposed scheme provides a formal methodology elementary for feature based design system development and operation in a structural way.
文摘Based on the definition of a logic structure feature to relate logically functional requirements to geometric representation independent upon detailed geometric representation, this paper presents an idea of logical structure modeling for computer aided conceptual design and makes attempt to establish a representation formalism of logic structure modeling. The definition and representation of logical structure feature are given and an assembly module definition for supporting top down conceptual design is also proposed. The proposed scheme contributes to several aspects of conceptual design research, especially to provide elementarily a formal methodology for computer aided conceptual design system development and operation.
文摘Minjian has become an important concept in recent scholarly research. It is widely used by scholars to indicate specific social and cultural spaces existing beyond the control of state power, therefore, minjian social-cultural spaces are more often than not marginal and peripheral. In the field of performing arts, minjian theatre refers to performances produced by private theatre companies as opposed to state-run groups. These private companies or grass-root groups, without the interference of the government, produce artistic expressions that reflect current social reality to a certain extent. For a long time, the study of minjian theatre has been framed as forms of resistance against the ideology propagated by state-run theatres. Based on this paradigm, this paper, through the case analysis of Shanghai minjian theatre companies, attempts to illuminate the production mechanism and developmental process of minjian theatres. In so dong, this paper will explore the aesthetic and social-political values of minjian theatres.
文摘X-ray photoelectron spectroscopy (XPS) and automatic titrimeter were nsed to study the relation be-tween pH and the transformation of the coordinate forms of P on goethite surfaces. The results showed thatfor a given P concentration, increasing the pH of suspension could cause a fast transformation of monodentatecomplexes of phosphate ions on goethite surfaces to binuclear ones. When lowering the PH, additional adsorp-tion of P occurred and the binuclear complexes reverted slowly to the monodentate ones. The dissociationand association of protons of the sorbed P caused by PH changes was considered to be a major reason lewtingto the transformation of the coordinate forms of P on the surfaces. The stability of binuclear surface complexof P was greater than that of monodentate complex. The possible reactions on the interface of goethite andsolutions with pH changes, and the reasons causing the different stabilities of the two coordinate P complexesare discussed in the paper.
文摘As a new form of artistic expression, film has gone through a history of more than 100 years in China. Focusing on the aesthetic taste of the underclass, popular literary tradition, which highlights appreciation habits of the citizen stratum, is the quintessence of Chinese traditional culture. Breaking through the mode of Western films, the early Chinese film, referring to artistic elements in story-telling script, fiction, and drama in Song and Yuan Dynasties, has created new film genres of ＂unofficial historical film＂ and martial-art film which are positive results of the localization of early Chinese films. Though the unofficial historical film failed in adapting the theme of popular literature, its groundbreaking significance is still worth approving
