An object-oriented approach is taken to the problem of formulating portable, easy-to-modify PDE solvers for realistic problems in three space dimensions. The resulting software library, Cogito, contains tools for writ...An object-oriented approach is taken to the problem of formulating portable, easy-to-modify PDE solvers for realistic problems in three space dimensions. The resulting software library, Cogito, contains tools for writing programs to be executed on MIMD computers with distributed memory. Difference methods on composite, structured grids are supported. Most of the Cogito classes have been implemented in Fortran 77, in such a way that the object-oriented design is visible. With respect to parallel performance, these tools yield code that is comparable to parallel solvers written in plain Fortran 77. The resulting programs are can be executed without modification on a large number of multicomputer platforms, and also on serial computers. The uppermost level of abstraction in Cogito concerns the problem of decoupling the numerical method from the PDE problem. The validity of these tools has been preliminarily demonstrated with a C++ implementation for one-dimensional problems.展开更多
Purpose： To develop a structured, rich media digital paper authoring tool with an object- based model that enables interactive, playable, and convertible functions. Design/methodology/approach： We propose Dpaper to ...Purpose： To develop a structured, rich media digital paper authoring tool with an object- based model that enables interactive, playable, and convertible functions. Design/methodology/approach： We propose Dpaper to organize the content （text, data, rich media, etc.） of dissertation papers as XML and HTML5 files by means of digital objects and digital templates. Findings： Dpaper provides a structured-paper editorial platform for the authors of PhDs to organize research materials and to generate various digital paper objects that are playable and reusable. The PhD papers are represented as Web pages and structured XML files, which are marked with semantic tags. Research limitations： The proposed tool only provides access to a limited number of digital objects. For instance, the tool cannot create equations and graphs, and typesetting is not yet flexible compared to MS Word. Practical implications： The Dpaper tool is designed to break through the patterns of unstructured content organization of traditional papers, and makes the paper accessible for not only reading but for exploitation as data, where the document can be extractable and reusable. As a result, Dpaper can make the digital publishing of dissertation texts more flexible and efficient, and their data more assessable. Originality/value： The Dpaper tool solves the challenge of making a paper structured and object-based in the stage of authoring, and has practical values for semantic publishing.展开更多
This paper presents a systematic approach of optimal design and control of a surface-mount, permanent-magnet synchronous torque motor for the next-generation machine tools. A step-by-step procedure of optimization int...This paper presents a systematic approach of optimal design and control of a surface-mount, permanent-magnet synchronous torque motor for the next-generation machine tools. A step-by-step procedure of optimization integrates multiple performance objectives and constraints to help the designer make the best decision on the final motor geometry from both design and control perspectives. In the perspective of design, a torque motor with concentrated windings and similar numbers of slots and poles may achieve the desired performance after optimization for multiple objectives, leading to a sinusoidal flux density for a nearly ripple-free torque distribution. From the control perspective, an optimal current waveform with an ideal shift angle is determined for each phase by aligning the current excitation with the back electromotive force. Both design and control of the surface-mount, permanent magnet machine are verified by the finite element method, and a prototype is fabricated for performance validation.展开更多
Motivational and cognitive aspects of spontaneous tool-use acquisition in species that do not do so habitually, remain an open but most relevant question. To address this, we studied captive kea (Nestor notabilis), Ne...Motivational and cognitive aspects of spontaneous tool-use acquisition in species that do not do so habitually, remain an open but most relevant question. To address this, we studied captive kea (Nestor notabilis), New Zealand mountain parrots renowned for their playful cleverness. The majority of adolescent, but not the adult kea, showed a toddler-like motivation to insert objects into empty tubes and also spontaneously used objects in order to eject food from inside a tube. This parallel what is known from object exploration in large brained mammals and shows for the first time in a habitually non-tool using bird that such a technical innovation is based on object-combining acquired outside the foraging context.展开更多
文摘An object-oriented approach is taken to the problem of formulating portable, easy-to-modify PDE solvers for realistic problems in three space dimensions. The resulting software library, Cogito, contains tools for writing programs to be executed on MIMD computers with distributed memory. Difference methods on composite, structured grids are supported. Most of the Cogito classes have been implemented in Fortran 77, in such a way that the object-oriented design is visible. With respect to parallel performance, these tools yield code that is comparable to parallel solvers written in plain Fortran 77. The resulting programs are can be executed without modification on a large number of multicomputer platforms, and also on serial computers. The uppermost level of abstraction in Cogito concerns the problem of decoupling the numerical method from the PDE problem. The validity of these tools has been preliminarily demonstrated with a C++ implementation for one-dimensional problems.
基金the Chinese Academy of Sciences for the Rich Media Digital Dissertation Authoring Tools iDissertation project
文摘Purpose： To develop a structured, rich media digital paper authoring tool with an object- based model that enables interactive, playable, and convertible functions. Design/methodology/approach： We propose Dpaper to organize the content （text, data, rich media, etc.） of dissertation papers as XML and HTML5 files by means of digital objects and digital templates. Findings： Dpaper provides a structured-paper editorial platform for the authors of PhDs to organize research materials and to generate various digital paper objects that are playable and reusable. The PhD papers are represented as Web pages and structured XML files, which are marked with semantic tags. Research limitations： The proposed tool only provides access to a limited number of digital objects. For instance, the tool cannot create equations and graphs, and typesetting is not yet flexible compared to MS Word. Practical implications： The Dpaper tool is designed to break through the patterns of unstructured content organization of traditional papers, and makes the paper accessible for not only reading but for exploitation as data, where the document can be extractable and reusable. As a result, Dpaper can make the digital publishing of dissertation texts more flexible and efficient, and their data more assessable. Originality/value： The Dpaper tool solves the challenge of making a paper structured and object-based in the stage of authoring, and has practical values for semantic publishing.
文摘This paper presents a systematic approach of optimal design and control of a surface-mount, permanent-magnet synchronous torque motor for the next-generation machine tools. A step-by-step procedure of optimization integrates multiple performance objectives and constraints to help the designer make the best decision on the final motor geometry from both design and control perspectives. In the perspective of design, a torque motor with concentrated windings and similar numbers of slots and poles may achieve the desired performance after optimization for multiple objectives, leading to a sinusoidal flux density for a nearly ripple-free torque distribution. From the control perspective, an optimal current waveform with an ideal shift angle is determined for each phase by aligning the current excitation with the back electromotive force. Both design and control of the surface-mount, permanent magnet machine are verified by the finite element method, and a prototype is fabricated for performance validation.
文摘Motivational and cognitive aspects of spontaneous tool-use acquisition in species that do not do so habitually, remain an open but most relevant question. To address this, we studied captive kea (Nestor notabilis), New Zealand mountain parrots renowned for their playful cleverness. The majority of adolescent, but not the adult kea, showed a toddler-like motivation to insert objects into empty tubes and also spontaneously used objects in order to eject food from inside a tube. This parallel what is known from object exploration in large brained mammals and shows for the first time in a habitually non-tool using bird that such a technical innovation is based on object-combining acquired outside the foraging context.
