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81.
Abstract: This paper describes the application of Artificial Intelligence techniques for plan generation, plan execution, and plan monitoring to automate a Deep Space Communication Station. This automation allows a communication station to respond to a set of tracking goals by appropriately reconfiguring the communications hardware and software to provide the requested communications services. In particular this paper describes: (1) the overall automation architecture, (2) the plan generation and execution monitoring AI technologies used and implemented software components, and (3) the knowledge engineering process and effort required for automation. This automation was demonstrated in February 1995, at the DSS13 Antenna Station in Goldstone, CA on a series of Voyager tracks and the technologies demonstrated are being transferred to the operational Deep Space Network stations. 相似文献
82.
In this paper, we derive an output tracking error model based on signals filtered from plant input and output, and then present a new output-based adaptive iterative learning controller for repeatable linear systems with unknown parameters, high relative degree, initial resetting error, input disturbance and output noise. The proposed controller solves the important robustness issues without assuming the bounds of uncertainties to be sufficiently small and can be applied to high relative degree plants without using output differentiation. Control parameters are updated between successive iterations so as to compensate for unknown system parameters and uncertainties. It is shown that the internal signals inside closed-loop learning system remain bounded and the output tracking error will asymptotically converge to a profile tunable by some design parameters. Furthermore, the learning speed is easily improved if the learning gain is increased. 相似文献
83.
Tiwari VS Luanje AT Kalluru RR Yueh FY Singh JP 《The Review of scientific instruments》2011,82(4):043108
An integrated fiber optic Raman sensor was designed for real-time, nonintrusive detection of liquid nitrogen (LN(2)) in liquid oxygen (LO(2)) at high pressures and high flow rates. This was intended to monitor the quality of LO(2) in oxidizer feed lines during the ground testing of rocket engines. Various issues related to optical diagnosis of cryogenic fluids (LN(2)/LO(2)) in supercritical environment of rocket engine test facility, such as fluorescence from impurity in optical window of feed line, signal-noise ratio, and fast data acquisition time, etc., are well addressed. The integrated sensor employed a frequency doubled 532-nm continuous wave Nd:YAG laser as an excitation light source. The other optical components included were InPhotonics Raman probes, spectrometers, and photomultiplier tubes (PMTs). The spectrometer was used to collect the Raman spectrum of LN(2) and LO(2). The PMT detection unit was integrated with home-built LABVIEW software for fast monitoring of concentration ratios LN(2) and LO(2). Prior to designing an integrated sensor system, its optical components were also tested with gaseous nitrogen (GN(2)) and oxygen (GO(2)). 相似文献
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86.
Abstract Among the parameters that affect photolithography, the most important are exposure and development time which affect the coating photoresist characteristics. This study further researches the relationship between the exposure and development time using a high speed image inspection system, and the relationship between the development time and photoresist depth using a Scanning Probe Microscope (SPM). A partial scan CCD camera and high speed frame capture card were used to obtain the photoresist development processing parameters. The experimental results verified that this imaging system provides an economical and effective method for producing a micro‐photo‐etched product. It is expected that these experiments can also offer some good references useful in the micro electro mechanical industrial field. 相似文献
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88.
In semiconductor manufacturing, hot lots are to provide marketing and engineering with extra flexibility regarding delivery lead times, and in turn enhance its competitive advantages against other companies. On the other hand, hot lots are among major sources of disruption of the smoothness of the manufacturing flow. They can lead to a significant increase of cycle time of normal lots, and in turn result in delayed delivery times and serious service deteriorations. Due to the complex nature of semiconductor manufacturing, evaluating the impact of hot lots on the cycle time of normal lots presents major challenges. In this paper, we propose a methodology, called progressive simulation metamodelling (PSM), that allows for an efficient development of the response surface between the cycle time of normal lots and the percentage of hot lots in semiconductor manufacturing. The response surface generated by the proposed PSM is like an easy-to-use analytical model, but with the fidelity of simulation that takes into account all important manufacturing details. The specially-designed mechanisms, including identifying the critical region and sequentially adding design points in the critical region, further grants PSM computational advantages compared to the traditional response surface method. An empirical study conducted in collaboration with a semiconductor company validates the viability of PSM in real settings. 相似文献
89.
Abstract Two optic fiber sensing systems for temperature and voltage have been developed which utilize the mode‐mode interference of the two orthogonally polarized modes, HEx II and HEy II, in two commencal polarization‐maintaining fibers (bow‐tie and elliptical core fibers). A package of controlled programs in a Macintosh computer, which can record and process all related data automatically, is established for temperature sensing. The signal drifting problem in voltage sensings has been investigated, and the elimination of signal drifting is obtained by the phase tracking with direct current technology The agreement between the sensing results for temperature and dynamic voltage and those predicted by experimental principles is satisfactory, which confirms the validity of the developed sensing systems. 相似文献
90.
A study on the formation of a measurement scale for the environmental quality of Taiwan’s long-term care institutions by the Delphi method 总被引:1,自引:0,他引:1
Yen Ping Hsieh Yen Wen Hsieh Chia Ching Lin Chien Wen Yeh Sing Chiao Chang 《Journal of Housing and the Built Environment》2012,27(2):169-186
This study used a two-round modified Delphi technique with a questionnaire survey in order to reach a consensus for the questionnaire; the survey was conducted from September to December 2009. The six indicators for the environmental quality of long-term care institutions in Taiwan are (1) indoor environmental quality, (2) safety equipment for the prevention and management of disasters occurring in residents?? daily lives, (3) provision for assistive devices for residents?? daily use, (4) provision for privacy and individualized space, (5) provision for comfortable and decorated indoor environments, and (6) provision for social interaction space. The scale included 34 items with an acceptable number of panel members and acceptable construct validity. Panel members all highly approved of Indicators 1, 2, and 6. Although they approved of Indicator 3, they suggested that caregivers at institutions should replace the functions of living assistive devices. They approved of Indicator 5; however, they questioned the method for providing comfortable and decorated environments. They approved of Indicator 4; however, they suggested that private space need not be provided in the living room of the institution. In terms of long-term care institution environments in Taiwan, Indicators 1, 2, and 6 were important for protecting residents?? physical and psychological well-being and improving their social interactions. Indicator 3, although important, could be directly replaced by caregivers. Indicator 5 required more implementation methods, while Indicator 4, the living room of the institution, was considered unnecessary. 相似文献