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991.
An important aspect of plant operation is preventive maintenance of electrical apparatus. Local thermal overloads or bad electrical connections often appear as localized hot spots in energized electrical equipment. A survey of the use of infrared detection systems for location of such hot spots is presented. A tutorial introduction to infrared detection and imaging systems is given with emphasis on the requirements imposed by this particular application. Following this, a survey of commercially available systems suitable for remote detection of hot spots is presented. Finally, the highlights of new developments in infrared technology are discussed. 相似文献
992.
Use of demographic variables to predict overall level of performance on the Halstead-Reitan Battery.
Karzmark Peter; Heaton Robert K.; Grant Igor; Matthews Charles G. 《Canadian Metallurgical Quarterly》1984,52(4):663
Developed and cross-validated an equation that uses demographic variables (sex, age, education, race, occupational categories) to predict average level of performance on the Halstead-Reitan Neuropsychological Test Battery by using a sample of 491 15–81 yr old neurologically normal Ss (mean WAIS IQ 112.8). Regression analysis predicted 65% of the variance in the Average Impairment Rating (59% in cross-validation). It is concluded that demographic variables are useful in providing a context for evaluation of cognitive functioning in Ss with known or suspected brain disorders. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
A continuous-flow differential reactor was used to obtain rate equations for the reaction of thiophene and hydrogen over coal mineral matter and a commercial cobalt-molybdate catalyst (Nalcomo 471). Coal mineral matter in its least altered state was obtained by low temperature ashing of Western Kentucky ?9 and ?11 coals in an oxygen plasma. Conversion was determined from the C4 gases separated by gas chromatography. Pretreatment of both coal mineral matter and catalyst with hydrogen sulfide increased thiophine reaction rates considerably, but introduction of the gas with reactants markedly decreased the rate. 相似文献
994.
MT Rademaker MA Fitzpatrick CJ Charles AM Richards MG Nicholls EA Espiner E Sybertz 《Canadian Metallurgical Quarterly》1996,27(3):439-446
OBJECTIVE: Due to the elevated levels of hematopoietically active cytokines such as tumor necrosis factor (TNF) and granulocyte macrophage colony stimulating factor (GMCSF) in rheumatoid arthritis (RA) serum and synovium, the increased bone marrow activity in RA, and the effectiveness of GMCSF in mobilizing progenitor cell release from the bone marrow into the periphery, we hypothesized that hematopoietic progenitors are altered in the peripheral blood (PB) of patients with RA. METHODS: Flow cytometry assisted cell surface analysis was employed to compare the distribution of myeloid (CD34+CD33+), B lymphoid (CD34+CD10+), and erythroid (CD34+CD71+) committed progenitor cell subsets in the PB of healthy controls and patients with RA. Since RA and Sjogren's syndrome (SS) are related autoimmune disorders, primary SS PB was also investigated. RESULTS: Only those patients with RA exhibiting clinically active disease (RA-A) demonstrated increases in myeloid and B lymphoid progenitor cell subsets. Growth of RA-A progenitors in cytokines promoting myelopoiesis (GMCSF, TNF, stem cell factor) produced increased monocyte and dendritic cell progeny, in support of the flow cytometry data. Lineage committed (CD34+CD38+) progenitors were increased in SS PB (p <0.03). However, these did not correlate with either the myeloid, erythroid, or B lymphoid lineages. CONCLUSION: Distinct alterations in the distribution of PB progenitors are present in RA and primary SS. Since progenitor cells retain a proliferative capacity, their infiltration into the synovial/glandular environment may contribute to the accumulation of inflammatory cells within these sites. We propose that PB progenitors enter the diseased microenvironment through similar mechanisms as mature hematopoietic elements. 相似文献
995.
An important phase within the overall residential land development process is preliminary project planning, which is a highly coordinated effort involving a number of decisions that are made by a variety of individuals. One critical decision faced by the project owner and the development team, during the preliminary planning phase, is the initial selection of the most appropriate site for a proposed conceptual development plan. The scope of this paper deals with (1) formulating a model for the preliminary planning phase of residential site selection; and (2) developing an associated decision support system that can assist the decision makers during this phase of the project. The analytical hierarchy process was the decision making theory used in the site selection decision support system. Analytical hierarchy process uses a hierarchical structure comprising both quantitative and qualitative factors that are based on factual data and the knowledge and experience of the decision makers. 相似文献
996.
CAVITATIONMODELINGWITHACFDAPPROACH¥JinzhangFeng;ManishDeshpande;CharlesL.Merkle(PropulsionEngineeringResearchCenter,Departmen... 相似文献
997.
Charles H. Lochmüller Larry S. Wigman Barbara S. Kitchell 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1987,40(1):33-40
A new method was developed to produce uniform spherical magnetic carrageenan-gel particles suitable for the affinity chromatography purification of large molecules. A sol-phase of k-carrageenan is pumped into an air jet to produce an aerosol of gel particles. The particle size can be varied by adjusting the air jet velocity. The gel particles are stable in 0-5 mol dm?3 KCI to 190 psi. The gel particles were used to immobilize soy trypsin inhibitor for the affinity purification of trypsin. The affinity matrix was tested in a packed-bed separator, fluidized-bed separator and a magnetically-stabilized fluidized-bed separator with similar column capacity for each separator. 相似文献
998.
The authors propose a model of phonological assembly that postulates a multilinear representation that segregates consonants and vowels in different planes. This representation determines the online process of assembly: Consonants and vowels are derived in 2 consecutive cycles that differ in their automaticity. The model's temporal properties resolve critical contradictions in the phonological processing literature. Its claims are further supported by a series of English-masking and English-priming experiments demonstrating that the contributions of consonants and vowels depend on target exposure duration and differ in their susceptibility to digit load. One methodological implication of the model is that regularity effects are not necessary evidence for assembly. This claim is supported by naming studies showing that vowel assembly requires long target durations, but short target durations permit consonant assembly despite null evidence for vowels. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
1000.
Partial scan flip-flop selection by use of empirical testability 总被引:1,自引:0,他引:1
Partial serial scan as a design for testability technique permits automatic generation of high fault coverage tests for sequential circuits with less hardware overhead and less performance degradation than full serial scan. The objective of the partial scan flip-flop selection method proposed here is to obtain maximum fault coverage for the number of scan flip-flops selected. Empirical Testability Difference (ETD), a measure of potential improvement in the testability of the circuit, is used to successively select one or more flip-flops for addition or deletion of scan logic. ETD is calculated by using testability measures based on empirical evaluation of the circuit with the acutal automatic test pattern generation (ATPG) system. In addition, once such faults are known, ETD focuses on the hard-to-detect faults rather than all faults and uses heuristics to permit effective selection of multiple flip-flops without global optimization. Two ETD algorithms have been extensively tested by using FASTEST ATPG [1, 2] on fourteen of the ISCAS89 [3] sequential circuits. The results of these tests indicate that ETD yields, on average, 35% fewer uncovered detectable faults for the same number of scanned flip-flops or 27% fewer scanned flip-flops for comparable fault coverage relative to cycle-breaking methods.This work was performed while the author was with the University of Wisconsin-Madison. 相似文献