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231.
A method for testing the interconnections of ordinary static RAMs with a processor that has a boundary-scan register and an IEEE 1149.1 test-access port is described. The method uses an enhanced boundary-scan-register design that manipulates the test-access-port controller states to meet the static RAM's timing constraints. The implementation is more economical than a boundary-scan register that strictly conforms to IEEE 1149.1. Test operation is more efficient, requiring a third of the number of scan operations. A test-pattern set and a method for detecting and diagnosing the interconnection faults on RAMs are also described. The test-pattern set can be enhanced as necessary to increase coverage and diagnosing ability and to handle any RAM configuration. The implementation of the proposed boundary-scan register is independent of the test algorithm used. It is believed that the methodology is extendable to RAMs that use an access protocol different from the one described, for example dynamic RAMs and synchronous RAMs 相似文献
232.
Water retention times less than 3 h from inlet to outlet were necessary to meet new effluent requirements without extending the footprint of the existing plant. Nitrogen removal was required at the existing, high loaded, direct precipitation plant and space was not readily available. The staff at the VEAS WWTP took on the task to design a new process at their own risk. Selected solutions and ups and downs in the water treatment during the past 10 years of operations and further developments are presented in this paper. Always asking for well-proven solutions might make life easy. The intent of this paper is to encourage some of our colleagues to be more daring in their approach to new challenges. However, expect sleepless nights in order to solve the unexpected problems along the way. 相似文献
233.
T. H. Chang K. F. Pao S. H. Chen K. R. Chu 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(9):1415-1420
Self-consistent effects on the starting current of gyrotron oscillators are examined. Field profiles in the open cavity are shown to be sensitive to the interaction dynamics. This can either significantly raise or lower the oscillation threshold, particularly for the low-Q modes. The transition from resonant-mode oscillations at the low magnetic field to backward-wave oscillations at the high magnetic field is demonstrated. 相似文献
234.
System Test Planning of Software: An Optimization Approach 总被引:1,自引:0,他引:1
Chari K. Hevner A. 《IEEE transactions on pattern analysis and machine intelligence》2006,32(7):503-5099
This paper extends an exponential reliability growth model to determine the optimal number of test cases to be executed for various use case scenarios during the system testing of software. An example demonstrates a practical application of the optimization model for system test planning. 相似文献
235.
Contact-expressive devices could improve our lives-from practical improvements that let us interact with devices when other modalities are impossible, inappropriate, or inadequate to devices that have important consequences for physical well-being. We can also imagine using contact expressions in devices that are pleasurable, playful, artistic, or otherwise important to a human's experience. This paper discusses the technical development of sensor-motor systems, tactile interfaces, and technologies that can embody and understand affect. Contact-expressive devices are technologies that understand and use touch in meaningful ways-that can distinguish between a press and a caress. Also discussed are the following issues: technical requirements and the nature of contact expressions. Although a fairly large body of research exists regarding nonverbal communication, the majority of this work is on visual expression (facial expressions, physical appearance, direction of gaze, physical posture, and other visible forms of body language) and paralinguistics (such as vocal inflection, pitch, volume, and speech rate). Work needs to begin on studies of human contact with the goal of leveraging those insights for the design of contact-expressive devices-and work needs to begin on the implementation of technologies that have rich contact-expressive range and appeal. 相似文献
236.
V. V. Vavilova V. M. Ievlev A. P. Isaenko Yu. E. Kalinin Yu. K. Kovneristyi N. A. Palii B. G. Sukhodolov V. N. Timofeev 《Inorganic Materials》2003,39(1):72-76
The effect of pulsed photon annealing with energy densities from 1.4 to 42 J/cm2 for various lengths of time on the structure of the amorphous alloy Fe79P14.2Si4.4Mn2.2V0.2 was studied by x-ray diffraction, differential scanning calorimetry, and transmission electron microscopy. The results demonstrate that short-term irradiation with low energy densities leads to surface relaxation of the amorphous alloy, increases the strength of the surface layer, and reduces the internal-friction peak. Longer term photon annealing leads to crystallization of the alloy throughout the sample thickness. 相似文献
237.
238.
This paper examines the current status and methodologies of study of material and system reliability in Microelectromechanical Systems (MEMS). This includes: a review of the current literature in the area of MEMS regarding failure analysis experimental investigations; testing methods and philosophies for material characterization and possible mechanistic analytical solutions for estimating material properties. The paper proposes a reliability framework that encompasses all the available information. This statistical platform will enable the MEMS design engineer to distill all the available information in the literature into a stand-alone semi-empirical material reliability model, and a holistic system-level model for a complete system. 相似文献
239.
240.