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991.
Production pipelines of manufactory industries present several machines and robots in which the movements of interpolated axes are managed by computerized numerical controls (CNCs). These are typically synchronized with several other simpler actuators along the pipeline of production. CNCs have to be flexible, easily expandable, and reusable, when pipelines of production are frequently reconfigured to realize different arranged pipelines with different technical requirements. In this paper, the assessment of a flexible CNC for such reconfigurable pipelines is presented. The analysis has been focused on defining objective metrics that can be applied for assessing performance and feasibility of distributed controls for pipelines. The method proposed has been applied on the distributed control architecture defined in the MUPAAC ESPRIT HPCN (Multi Processor Architecture for Automatic Control, High Performance Computer Networking of the European Commission). MUPAAC architecture and prototype has been assessed in order to identify the critical configurations and the limits of the architecture. 相似文献
992.
993.
994.
The influence of changes in load conditions of the generator-transformer unit on the operating conditions of the 100% ground-fault protection of the generator stator winding based on the third-harmonic voltages was analyzed. The analyzed stator ground-fault protection system is by ratio of the voltages third harmonic in generator neutral and at the generator terminals. The third-harmonic voltages were determined on the base of the experimental tests (measurements) run in real conditions at changes in active and reactive load conditions of the generator. It was found that mainly the generator active load influences the voltage feeding the measuring element of ground-fault protection. Therefore, determining operating conditions of ground-fault protection the influence of the generator active and reactive load should be deeply considered. This can ensure the proper operation of the ground-fault protection based on the voltage third harmonics in the whole range of the changes in generator load. Considering the influence of changes in generator load on the third-harmonic voltages (feeding measuring element of the protection system) will allow eliminating irregular generator tripping as a result of unselective operation of these protections. 相似文献
995.
This paper presents a valve-regulated lead acid (VRLA) battery reserve life estimation scheme. The scheme is adaptive in both type and frequency of involvement. The scheme is based on capacity trending with the support of a number of state-of-health (SOH) indicators. These SOH indicators include accumulated thermal stress, float voltage, and indicators acquired from the start-of-discharge (coup de fouet) region. An implementation test case is given, indicating that the scheme is capable of providing an accurate estimation of reserve life long before the end of life. Furthermore, the estimation accuracy improves as the end of battery life approaches. 相似文献
996.
Fabrication and thermal characterization of a resistance temperature detector (RTD) heater and microthermocouples (MTs) on silicon substrates have been reported in this paper. The influence of film thickness and nickel-gold (Au) electroplating on RTD on its steady-state temperature with respect to its steady-state electrical power input and resistance is studied. Further, the thermal effects of multiple thermocouples in a thermopile as well as the effects of Au layers in the contact pads of the thermopiles on their open-circuit Seebeck voltage are studied. Therein lies the novelty of this paper. The in situ operating relationships for the RTD heater and the MT are provided 相似文献
997.
Industry widely uses rotary valves and blow tanks for the pneumatic conveying of products, each having their pros and cons depending on the specific application. This article shows the differing results obtained when low-velocity conveying a product through a common pipeline using both a drop-through rotary valve and a bottom-discharge blow tank feeder. A number of issues arise in the rotary valve system, the main one being rotary valve air leakage. A blow tank system, on the other hand, does not leak, as it is an enclosed system. The experimental results show dramatic differences in product throughput. Further exploration leads to a novel modification being made to the rotary valve system in an attempt to increase its capacity. The result of this modification shows a slight increase in output tonnage, but still significantly less than that obtained from the blow tank. 相似文献
998.
Epitaxial lamellar gallium selenide (GaSe) semiconductors have been grown on trench-patterned silicon (Si) substrates by molecular beam epitaxy. An intriguing star-like patterned morphology was identified by atomic force microscopy on these epilayers. This non-trivial feature can be correlated with the accumulation of stacking faults of two concurrent epitaxial domains around self-oriented triangular pits developed earlier on the Si(111) surface by the chemical etching. Crystallographic considerations show how the stars can be formed. 相似文献
999.
1000.
A. P. Vasil’ev V. P. Vasyukhno M. E. Netecha V. L. Vysotskii R. I. Kalinin A. A. Sarkisov A. Yu. Kazennov Yu. V. Sivintsev A. M. Chernyaev 《Atomic Energy》2006,101(1):506-511
The radioecological conditions which developed on the territory over the long operating time of the object of the naval fleet
in Guba Andreev are described. The results of an analysis of the sources of the real and potential danger and measures to
prevent dangerous effects for the environment and the workers at the time remediation work is performed are discussed.
__________
Translated from Atomnaya énergiya, Vol. 101, No. 1, pp. 49–55, July, 2006. 相似文献