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961.
N. N. Novikov O. V. Korovin Yu. V. Astapenko D. V. Overchenko 《Measurement Techniques》1996,39(6):607-612
This article considers the influence of changes in monitorability indicators on the operational characteristics of communications
equipment. For indicators of monitorability we take the depth of defect search, failure localizability, overhead, and others.
Among the operational characteristics, those considered include time to repair, probability of undetected failure, probability
of failure-free operation, etc. The results obtained make it possible to estimate, during the design phase, the influence
of changes in monitorability factors on the operational characteristics of equipment and to make selections that meet given
requirements.
Translated from Izmeritel'naya Tekhnika, No. 6, pp. 23–26, June, 1996. 相似文献
962.
Yu. N. Kryuchkov 《Journal of Engineering Physics and Thermophysics》1994,66(3):312-315
Expressions are obtained for calculating percolation characteristics of heterogeneous systems with the use of refined auxiliary relations in the entire range of their porosity (concentration of a disperse phase).Institute of Engineering Thermophysics, Academy of Sciences of the Ukraine, Kiev. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 66, No. 3, pp. 348–352, March, 1994. 相似文献
963.
控制系统的设计与仿真是着眼于充分掌握和运用反馈控制系统原理的非解析课件。控制系统的设计与仿真实验课作为广东机械学院计算机辅助教学的一部分已经在Novell局域网上开出.该课程的各种练习、例题、问题及实例教学鼓励学生自测和开发他们所学的知识.是特别适合自学的控制系统计算机辅助教学课程。 相似文献
964.
965.
The possibility of fabrication of ceramic tile from a mixture containing technogenic products including up to 20% cleaned mine water with a high content of calcium oxide and up to 35% alkali-containing waste is established. A nonfritted low-melting glaze is developed on the basis of sand, pegmatite, kaolin, zinc white, zircon concentrate, and calcium borate. The physicochemical properties of the crock and the coating are investigated. 相似文献
966.
Xing Li Zuoqing Wang Cheng Kuei Jen Viens M. Cheeke J.D.N. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1996,43(2):331-336
Theoretical and experimental investigations of thin-walled tube acoustic wave devices for gravimetric sensing applications are presented. Integrated sensor configurations have been demonstrated by employing a sol-gel processed thin piezoelectric lead zirconate titanate (PZT) film. This was coated coaxially on stainless steel tubes and interdigital transducers (IDT) fabricated as the transmitter and receiver on the curved tube surfaces. We have observed tube waves along both the axial and circumferential directions between 1 and 6.6 MHz. We have also analyzed the mass sensitivities of different modes propagating along the tubes and shown that high mass sensitivity can be achieved by keeping the tube wall thin 相似文献
967.
M. Dobson R. Rada C. Chen A. Michailidis A. Ulloa 《Journal of Computer Assisted Learning》1993,9(1):34-50
Abstract In an effort to reduce the expensive resource requirements in courseware production and to allow effective management of, and communication and collaboration between authors, a model is needed to harmonize the diverse theoretical backgrounds such a process requires. To this end we look at five abstract models which where chosen for their apparent appropriateness within the general area of collaborative authoring and reuse of multimedia courseware. These models consist of a functional model of hypertext, an infrastructure model for an open collaborative authoring system, two object-oriented communication models, and a courseware production model. We attempt a consolidation of these models and ultimately make several conclusions, which are exposed during a conceptual harmonisation. The principal conclusion is that a hypermedia logical model is not by itself adequate to support collaboration and reuse. Our modeling conclusions have driven the design of a system which will be implemented and tested. 相似文献
968.
The degree of polarization of radiation in an elliptical polarization-maintaining fiber and the polarization states of eigenpolarization modes of such fibers have been experimentally investigated in a wide spectral range. It has been shown that the elliptical fibers are uniform, homogeneously twisted fibers with elliptically polarized eigenpolarization modes. The ellipticity of the eigenpolarization mode is independent of fiber length and increases with wavelength, while the azimuth of the eigenpolarization mode is spectrally independent 相似文献
969.
旋转式伽玛刀的辐射剂量学 总被引:4,自引:0,他引:4
旋转式伽玛刀的辐射剂量学指标的物理测试在放射性医疗设备投放医院正式临床使用前是必不可少的,是对设备及其附件的设计、加工制造、安装以及电气控制系统等的全面综合性检定。用电离室作辐射剂量学的绝对测量,用胶片法进行相对测量,给出了测量结果并进行了讨论。 相似文献
970.
JM Schapiro L Arber D Lev D Weksler E Liberman A Winder S Berliner N Arber 《Canadian Metallurgical Quarterly》1995,62(4):298-301
Stress has a significant influence on the function of the human organism. A simple, rapid, inexpensive, and reliable marker for stress would therefore be of great value. We have recently noted that stress increases the state of leukocyte adhesiveness and aggregation in the peripheral blood. We evaluated 64 patients who had various degrees of congestive heart failure, a condition known to induce a state of physiologic stress, to verify whether a relation exists between the intensity of the stress response and the magnitude of leukocyte adhesiveness. Included in the 64 were 53 patients without congestive heart failure, 23 with compensated failure, 22 with significant congestive heart failure, and 19 with florid pulmonary edema. The percentage of aggregated leukocytes in these four group was 6% +/- 4%, 6% +/- 4%, 10.5% +/- 5%, and 15% +/- 14%. Values for the third and fourth group differed in a statistically significant way. Thus, with further investigation into additional stress-inducing conditions, the state of leukocyte adhesion and aggregation may prove to be a reliable marker for the detection of stress and an inexpensive tool for quantifying its severity. 相似文献