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1.
A model-based method for fault detection in tapping based on torque and radial forces is proposed. The method allows the identification of faults typical of a tapping operation including axial misalignment, tap runout, tooth breakage both singly and together. The validation experiments have been run on aluminum 356 workpieces for different combinations of process faults. Results have shown that the model predictions are in good agreement with the experimental radial force and torque signals under various fault conditions.  相似文献   
2.
Here, we describe the development of a reacting flow multi-species/combustion methodology, implemented as an extension to the differential reduced ejector analysis (DREA) computer program [Mathematical and computer modeling, vol. 31, 2000, p. 21; Appl. Math. Model. 25 (2001) 427; Comput. Math. Appl. 43(10–11); NASA Contractor Report, 1998]. Use of the single fluid IVP solver framework that was developed for the original DREA model has been directly coupled into the combustion formulation. With these modifications, the analysis has an elementary single step reaction Fuel+Oxidizer→Product combustion capability. Though approximate in nature, the simplicity and efficiency of the DREA formulation make it suitable for its original niche, namely design and preliminary design environments where more complex and expensive models may be inappropriate.  相似文献   
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Remedial services for children with reading problems are often allocated according to discrepancies between reading and IQ scores. Results of some recent research suggest, however, that IQ scores of poor readers do not covary with their levels of functioning in other cognitive domains. This study evaluated whether the external validity of IQ scores (from the Wechsler Intelligence Scale for Children—Revised [WAIS—R]) was moderated by reading levels within 2 separate samples of a total of 382 referred children (aged 7–16 yrs). It was found that IQ scores had expected correlations with external measures of verbal, visual-spatial, short-term memory, and arithmetic ability, and that these relations were invariant across levels of reading skill. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Comments on S. Harvey's (see record 1994-43015-001) article on using the Canadian Psychological Association's (CPA's) Code of Ethics for psychologists in an organizational case. T. J. Kline disputes the necessity of developing specific standards for particular areas of practice because she contends that the CPA code is meant to serve as a guide and a conceptual device, not a body of law. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Clinical and scintigraphic criteria are proposed for the diagnosis of segmental reflex sympathetic dystrophy. Eight patients met previously described clinical criteria for reflex sympathetic dystrophy with involvement limited to only a portion of the hand. The delayed phase of the three-phase radionuclide bone scan was found to be highly sensitive (100%) for this small group of patients. Consecutive bone scans (n = 127) performed during a 6-month period for a variety of upper extremity problems were reviewed, and a segmentally diffuse pattern of tracer uptake was found to be highly specific (98%) for segmental reflex sympathetic dystrophy. Recognition and documentation of a more localized form of reflex sympathetic dystrophy will allow earlier recognition and treatment, which is an important factor in a successful outcome for managing pain dysfunction disorders.  相似文献   
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Nonlinear boundary element analysis provides a more accurate and detailing tool for the design of switched reluctance machines than conventional equivalent-circuit methods. Design optimization through more detailed analysis and simulation can reduce development and prototyping costs and time to market. Firstly, magnetic field modeling of an industrial switched reluctance machine by the boundary element method is reported in this paper. Secondly, performance prediction and dynamic simulation of motor and control design are presented. Thirdly, magnetic forces that cause noise and vibration are studied, to include the effects of motor and control design variations on noise in the design process. Testing of such a motor in the NEMA 215-Frame size is carried out to verify the accuracy of modeling and simulation  相似文献   
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In a cross-sectional sample of 428 employees, the job demand-control-support and effort-reward imbalance job stress models were amalgamated and expanded to include modifiable risk factors and noncontrollable genetic factors related to cardiovascular disease (CVD) risk. With structural equation modeling, the constructs of lack of job resilience, lack of personal resilience, and job demand were used to examine how employer and employee factors related to psychosomatic strain and risk indicators of CVD. Negative perception of job demand predicted perception of lack of job resilience but not lack of personal resilience. Lack of job and personal resilience predicted strain. Women reported greater strain than men. CVD risk was predicted by strain, age, sex, and family history. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
In behavioral tests, rats performed learned escape responses to thermal stimulation of the paws by 44.0. 47.0. or 0.3 degrees C. Licking, guarding, and jumping reflexes were evaluated at these temperatures. The frequency, latency, and duration of escape and reflex responses were compared and were related to hind-paw skin temperatures measured during stimulation of awake and anesthetized rats. The duration and latency of escape from heat were appropriately related to stimulus intensity. Escape occurred reliably for each intensity. Reflexes occurred unreliably and at long latency to 44.0 or 0.3 degrees C and were not appropriately related to heat intensity. The reflexes were relatively insensitive to thermal nociceptive stimulation other than heating of the skin at a high rate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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