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161.
D. L. Judge H. S. Ogawa D. R. McMullin P. Gangopadhyay J. M. Pap 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2002,29(12):502-1968
The SOHO Solar EUV Monitor has been in operation since December 1995 onboard the SOHO spacecraft. This instrument is a highly stable transmission grating solar extreme ultraviolet spectrometer. It has made nearly continuous full disk solar irradiance measurements both within an 8 nm bandpass centered at 30.4 nm and throughout the 0.1 to 50 nm solar flux region since launch. The 30.4 nm flux, the 0.1 to 50 nm flux and the extracted soft X-ray (0.1 to 5 nm) flux are presented and compared with the behavior of solar proxies. 相似文献
162.
A data fusion model consisting of several levels of parallel decision fusions is considered. Global optimization of such a model is discussed to obtain the fusion rules for overall optimal performance. The reliability analysis of the proposed model is carried out to establish its superiority over the existing parallel and serial fusion models 相似文献
163.
Geoffrey E. Perry 《Space Policy》1989,5(4):279-287
For many years the world-famous Kettering Group of amateur satellite observers have confounded many more ‘official’ organization with their accucary in tracking Soviet space launches. In this article the group's founder, Geoffrey E. Perry, MBE, presents his personal perspective on current developments in the Soviet space programme. The USSR's increased openness about non-sensitive issues is to be welcomed, he concludes, but the Kettering Group has work to do yet. 相似文献
164.
An electric vehicle (EV) energy management system (EMS) developed to accurately predict and extend the usable driving range and the life of the battery pack is discussed. The EMS monitors and records battery state of charge, vehicle performance, power consumption of key components, and driver's actions. Convenient drive inputs in conjunction with memorized energy consumption profiles allow accurate prediction of driving range and selection of appropriate recharging profiles. EV range extension is accomplished by identifying inefficient use of energy, resulting in EMS modification of energy usage by offending subsystems or EMS suggestion to the driver of improved driving habits or vehicle use. Factors affecting the accuracy of range prediction and the amount of range extension are described 相似文献
165.
The design of fault-tolerant distributed control systems is discussed. The application described is a generic flight control system (FCS) for a fighter aircraft. The system is designed for high redundancy and expandability to meet various requirements. The communication network is based on the fiber distributed data interface (FDDI), which provides a high level of electromagnetic interference resistance and reliability. The choice of fiber optic media also provides an extremely high bandwidth and tremendous growth capability for future communications needs. This study is not specific to FDDI or flight control systems. The methods and configurations presented should be applicable to many real-time control implementations 相似文献
166.
R. Wickramatunga 《Space Policy》1991,7(1)
Parties to the Registration Convention are committed to providing the United Nations with certain information about objects they launch into space. This report describes the categories of information required, outlines the inadequacies of the present Register and suggests modifications. 相似文献
167.
168.
The NASA Advanced Communications Technology Satellite (ACTS) program will conduct high-data-rate experiments that will be applicable to the emerging broadband services of the telephony market. The existing broadband integrated services digital network (BISDN) services and delivery method as defined by the International Consultative Committee for Telephone and Telegraph (CCITT) and satellites' role in provisioning those services are discussed. The ACTS experimental efforts are summarized 相似文献
169.
The governments’ priority and budgets for space activities are steadily decreasing and the importance of space activities is not any longer reaching the front pages of the newspaper, as in the 1960s. On the other hand in Europe the people, at large, have shown an important interest and support for space activities. A contribution to bridge the gap between decreasing funding and important support of citizen can come from teaching space policy in universities as well as in special workshops for government, industrial and military circles. The paper will outline a course that fulfils this goal. 相似文献
170.
G. Sachs 《Aerospace Science and Technology》2003,7(8):160-631
A longitudinal-lateral control coordination and simplification concept is considered for a tunnel/predictor display, which presents the command flight path and a specified future aircraft position in a 3-dimensional format to the pilot, for improving flight path control. A basic element of the proposed concept is the generation of common longitudinal-lateral transfer characteristics of the predictor-aircraft system for the crossover frequency region. Control coordination is supported by a dynamics similarity between the longitudinal and the lateral response characteristics of the predictor position in closed-loop pilot control actions. The control coordination and simplification concept is considered to support the pilot in manual flight path control, directed at an enhancement of his control performance and at a reduction of his workload. Results from pilot-in-the-loop simulation experiments support the theoretical findings and show the effectiveness of the proposed predictor concept with control coordination. 相似文献