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961.
Gregory L.   《Computer aided design》2002,34(14):1055-1062
Boeing has been working on the development and implementation of STEP AP 210 since its inception. Using a combination of internally funded activities, external government contracts and multi-company pilots, Boeing has developed prototype tools to utilize AP 210 and is poised to move these tools into production. This paper begins with a brief overview of STEP and AP 210. The status of available AP 210 vendor translators (data generators), along with viewers and analysis programs (data consumers) is covered. Discussion continues with present and planned usage of AP 210 in several companies with the primary emphasis on implementation at The Boeing Company. The document concludes with a summary of key points.  相似文献   
962.
963.
There are several psychiatric illnesses that are difficult to treat with drugs. Among these are schizophrenia, manic depression, and profound depression; many of these may involve a tendency to suicide. In 1938 U. Cerletti conducted convulsive experiments on pigs using power-line current applied to electrodes at various sites. The effect of current duration was also investigated. As yet it is not known which areas in the brain are the optimum targets for the therapeutic use of cranially applied current to treat psychiatric illnesses, although the frontal lobes appear to be the best targets.  相似文献   
964.
Writing project reports is an important part of the engineering curriculum at Singapore universities. One important section of the formal report is the literature review. Most universities around the world provide guidelines on writing reviews, emphasizing that plagiarism is unethical. However, these guidelines do not offer explicit training on how to avoid plagiarism. In order to write academically acceptable reviews while avoiding copying from source materials, students face a major challenge and resort to employing various strategies to cope with the task. In this study, we examined the literature review sections of final year project reports to find out how engineering undergraduates in a Singapore university cope with writing reviews and to suggest ways in which they can extend their skills to improve their literature reviews.  相似文献   
965.
An electromechanical filter using trapped-energy flexural modes in a rectangular plate is proposed. The filter is amenable to fabrication by planar techniques and it can operate in the l.f. range, including the voice band. Bandwidth is easily controllable. A considerable gain in size can be obtained with respect to flexural bar filters.  相似文献   
966.
967.
This paper comes to fill a gap in watermarking theory, analyzing the exact performance of the scalar Costa scheme (SCS) facing additive Gaussian attacks when the usual approximation of high-resolution quantization is not valid, thus taking into account the host statistics. The analysis is focused on the assessment of the probability of error, showing new results, an although it is valid in a general scenario, its practical interest is increased when SCS is used in conjunction with the so-called spread-transform. The accomplished reformulation of the problem also permits to show that the achievable rate of SCS is never worse than that of classical spread-spectrum-based methods, as it was thought so far, and allows to establish interesting links with spread spectrum and the Improved Spread Spectrum method.  相似文献   
968.
The electric field (EF) model was first developed on a "breadboard" using physical electric components (e.g., resistors, capacitors, batteries) and was then modeled mathematically by a series of differential equations and matrix equations and simulated on a large computer (CDC-6400). The results obtained by the two methods agreed very closely. However, these two methods of analysis are quite cumbersome. Therefore, in order to simplify the EF simulation, we wanted to model it on the PSpice program. In this article we discuss how we succeeded in demonstrating transmission of excitation from cell to cell in cardiac muscle and smooth muscle based on EF transmission at the cell junctions.  相似文献   
969.
The superconducting dipoles developed as part of the UNK project have reached a magnetic field 6 T at a rate of up to 0.8 T/sec. Experimental data are presented on the conditioning, rate dependences, and dynamic losses for magnets with two types of superconducting cable (zebra and oxide). Possible ways to decrease the heat release in a dipole operating in rapid-cycling magnetic fields are examined. The results of an analysis of heat release and temperature conditions are presented for a dipole with a winding made of improved current-carrying components.  相似文献   
970.
A modern concept of cost-effective digital signal processing hardware for measuring and analysing data from experiments investigating turbulent two-phase flows is presented. Using an array processor together with an appropriate analog-to-digital converter, conventional turbulence characteristics such as turbulence spectra, correlation functions, turbulence intensities and — scales can be evaluated in real time.  相似文献   
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