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91.
In this paper, we present an architecture for a run-to-run supervisory process control system that allows the engineer to tailor the form of control for specific processes. The architecture supports different degrees of control, from model-based control to statistical process control to diagnosis. The architecture is compatible with different techniques for model optimization, data acquisition and analysis, and model adjustment and feedback. A primary feature of this architecture is that engineers can define processes In terms of their desired effects, and use process models that transform those effects into machine settings. We have used object technology as the basis for our design and implementation of the architecture. Object-oriented modeling provides the flexibility required to support the varying degrees of control required in a large-scale manufacturing facility. In this paper, we define the components of the architecture, and describe in detail a process control system that was built with this architecture and used in the Computer Integrated manufacturing (CIM) system built for the Microelectronics Manufacturing Science and Technology (MMST) demonstration facility. Although the architecture was developed for the purpose of controlling semiconductor manufacturing processes, the principles behind the architecture may be applied to the control of any process  相似文献   
92.
Germanium films deposited under simultaneous argon ion irradiation show substantially better adherence on glass and other substrate materials than conventionally produced films.The ion bombardment leads to a strengthening of the interfacial bonding, an effect believed to be associated with a thin layer of intermediate composition produced at the substrate surface by ion knock-on processes. In addition irradiation causes a significant reduction in film stress.  相似文献   
93.
The mechanisms by which BCG exerts its antitumour activity remain unclear. Attachment of BCG to the bladder via FN has been shown to be an important step in initiating its antitumorigenic activity. The mechanism(s) by which BCG operates requires LAK cells, BCG-activated killer cells, T lymphocytes (CD4) helper cells and CD8 suppressor/cytotoxic cells) and monocytes. The optimal route of administration is intravesical. The efficacy of a BCG vaccine depends on the viability, dose and strain. Differences in efficacy and side-effects have not been shown between different strains. Low-dose regimens successfully protect from recurrences, with fewer side-effects. The initial schedule of BCG is a course of six instillations in 6 weeks; when the patient fails this course, two possibilities arise. The first is maintenance therapy; response rates improve but there is more local and systemic toxicity. The second is a further 6-week course, and this seems most useful in those with a sustained response to the initial treatment. The clinical response to BCG therapy can be monitored using cytokine measurements or p53 determinations. Toxicity remains a major problem in BCG treatment and triple antituberculosis combination therapy should be given for 3 months in those with severe systemic side-effects. The use of prophylactic isoniazid is not recommend to decrease side-effects. The clinical results of BCG have been good, with success rates of 58-100%, with a minimal follow-up of one year in prophylaxis. BCG seems superior to intravesical therapy, but at the cost of inducing more adverse effects. BCG is not indicated for low- and intermediate-risk patients, in whom chemotherapy is the first choice. BCG can also be used to eliminate tumour after an incomplete TUR, or in patients who are unfit for surgery, with a 60-70% success rate. The primary and best treatment for CIS is intravesical BCG; encouraging results have been reported, with success rate of 42-83% after a minimal follow-up of one year. Although currently BCG seems to be the choice for high-risk superficial TCC, many questions remain unanswered, especially about the mechanism(s) of action, the optimal dose and clinical schedule.  相似文献   
94.
The Allen and Koomen planner is intractable in two ways: the Allen interval algebra is an intractable temporal reasoner, and the collapsing problem introduces a large branching factor in the search space for a solution plan. We define independence and dependence for networks to address both problems. Independence is used to find a decomposition of an interval network, and dependence is used to focus search when faced with the collapsing problem.  相似文献   
95.
96.
Report of illnesses caused by aldicarb-contaminated cucumbers   总被引:1,自引:0,他引:1  
During May and June of 1985 the Health Protection Branch and several other agencies were involved in the investigation of over 300 reports of illness reported in the Vancouver area of British Columbia, Canada. Symptoms reported included nausea, vomiting, dizziness, muscle fasciculation and blurred vision. A review of the onset of symptoms and food consumed suggested that at least 140 people had become ill from eating cucumbers adulterated with a carbamate pesticide. The presence of residues of aldicarb in cucumbers from one particular producer was confirmed by laboratory analysis.  相似文献   
97.
98.
AIDS, whether real or threatened, poses a radical challenge to the psychological, social, and practical adaptation of individuals at various stages of human immunodeficiency virus (HIV) disease. The challenge arises from multiple sources, including disease progression, social discrimination, bereavement, pressure for life-style change, and neurological impairment associated with HIV brain infection. The consequences of this challenge to people with HIV infection, AIDS-related complex, AIDS, and AIDS dementia complex are reviewed. The potential for both personal crisis and personal growth in response to this challenge is highlighted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
100.
STUDY OBJECTIVE: To evaluate the usefulness of routine radiographs and arterial blood gases in children with blunt trauma. DESIGN: Retrospective chart review. TYPE OF PARTICIPANTS: Ninety patients who met triage criteria for our trauma team evaluation and who were less than 15 years old were evaluated. Patients with a Glasgow Coma Scale score (GCS) of 15 (lie, mild to moderately injured children) were the focus of this study. METHODS: Children seen from May 1991 through August 1992 had charts reviewed systematically and within 24 hours of emergency department evaluation. Standard radiologic evaluation, including cervical-spine, chest, and pelvic radiographs, as well as arterial blood gas analysis, were obtained. The severity of injury was graded according to the Modified Injury Severity Scale. RESULTS: The mean age of patients was 6.4 years, and the injuries observed were exclusively extremity fractures. The correlation between physical examination findings and radiologic evaluation was assessed. Forty-three patients had an abnormal physical examination (ie, gross deformity, limitation of motion, or pain), and 26 had a fracture identified on radiograph. Forty-seven patients had a normal physical examination and none had a fracture identified on radiograph (P < .001; sensitivity of positive signs and symptoms, 100%; false-negative findings, 0%). Four patients with abnormal blood gases are described. No patient had any vascular or solid organ injury identified. CONCLUSION: In children with a GCS score of 15, selected radiologic and laboratory tests based on clinical findings are recommended. Careful observation and repeat examinations by trained clinicians can select a group of children at low risk for occult injury.  相似文献   
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