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991.
992.
A novel hierarchical intelligent controller configuration is proposed using an artificial neural network as a control-mode classifier in the supervisory level and a set of pre-designed controllers in the lower level. Controller outputs are modified nonlinearly by the classifying signals in a structure resembling one artificial neuron with adaptively changed weights. The lower-level local controllers are implemented using neural networks. An illustrative example of this approach is based on the transient stabilization of a single-machine infinite-bus system studied in Flexible AC Transmission Systems (FACTS) research. 相似文献
993.
994.
233 undergraduates (162 women and 71 men) completed a demographics questionnaire and measures of career-decision-making (CDM) self-efficacy (K. M. Taylor and N. E. Betz, 1983), CDM attitudes (J. O. Crites, 1978), and CDM skills (D. E. Super et al, 1981). Results revealed that CDM self-efficacy was moderately and positively related to CDM attitudes and age of participants (p? 相似文献
995.
R Lewis 《Canadian Metallurgical Quarterly》1998,24(3):95-97
The management of pain in patients with burn wounds is complex and problematic. Burn-wound pain is severe, inconsistent and underestimated. Patients experience severe pain, especially during procedures, until wound healing has occurred. A multi-modality approach is needed for effective management of pain, which requires an understanding of the mechanisms of pain. Altered pharmacokinetics and pharmacodynamics in burn-wound patients makes drug actions unpredictable. Opioids alone are seldom sufficient for pain control. The multi-modality approach includes the use of opioids and non-steroidal anti-inflammatory, anxiolytic and alternative drugs. Ketamine has been found to be a useful agent for analgesia in burn-wound patients; a dose of 10 mg/kg qid per os was found to be an effective adjunct to pain therapy. 相似文献
996.
BACKGROUND: In the outpatient use of tuberculin skin testing (purified protein derivative [PPD]), it is at times inconvenient to have a patient revisit for interpretation. Therefore, we assessed patients' ability to self-interpret these test results. METHODS: In keeping with prior custom, patients were seen by an experienced nurse, who performed skin testing with PPD intermediate strength as well as mumps and Candida anergy control tests in some cases, and explained the procedure. The patients were asked to return 48 to 72 h later, at which time one of the researchers recorded their test interpretations before they were again evaluated by the nurse. RESULTS: Sixty-eight patients were studied, of whom 59 returned at appropriate interval. Eighteen patients had a positive PPD test reaction of 10 to 20 mm induration, which only one patient correctly identified as a positive test result. However, positive anergy control tests were correctly interpreted in 10 of 27 cases. CONCLUSION: The small number of positive PPD test result recognition by these patients may be partially attributed to their lack of education, as well as foreign birth and denial of illness. PPD results should be checked by an experienced professional. 相似文献
997.
This review shows that quantitative measurements of fundus reflectance can be described by models that explicitly incorporate anatomical and physical properties of the fundus tissue. Newer techniques examine the fundus in ways fundamentally different from conventional optics, and must be included in this approach of measurement and modeling. The importance of the “inner surface reflector” (ISR) for tomographic imaging warrants more study of its optical properties, particularly its directional reflectance. For example, because the surface of a glaucomatous optic disc can slope steeply into the cup, the directional reflectance of the ISR may affect its apparent topography and thus the reproducibility of measurements of cup size 相似文献
998.
999.
The performance of two distributed channel assignment algorithms which use coexistence etiquettes for point to point links are considered by the authors. It has been found that selecting channels prior to transmission at the transmitter as opposed to the receiver, supports greater offered traffic with the additional advantage of a less complex protocol 相似文献
1000.
Thermally insulating behaviour of single and multiple layers of textiles under wind assault 总被引:1,自引:0,他引:1
One or more layers of textiles can provide a thermal resistance between the human body and its environment, and so help maintain the body in a thermally comfortable state. The effect of wind on and its penetration through such thermal cladding is examined experimentally. 相似文献