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排序方式: 共有934条查询结果,搜索用时 187 毫秒
1.
Belcher Calvin H. Zheng Baolong MacDonald Benjamin E. Langlois Eric D. Lehman Benjamin Pearce Charles Delaney Robert Apelian Diran Lavernia Enrique J. Monson Todd C. 《Journal of Materials Science》2022,57(9):5518-5532
Journal of Materials Science - For transformers and inductors to meet the world’s growing demand for electrical power, more efficient soft magnetic materials with high saturation magnetic... 相似文献
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Uses principles of latent trait theory to derive conditions under which mean differences on an observed variable are indicative of mean differences on an underlying construct, focusing on the logistic curve as a model for describing the relation between the observed variable and construct. In this situation, and with normally distributed scores on the construct, a t test comparing groups on the observed variable produces correct inferences at the construct level only if group variances on the construct are homogeneous or the difficulty level of the test equals the mean ability level of the examinees. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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We introduce a generalization of a deterministic relaxation algorithm for edge-preserving regularization in linear inverse problems. This algorithm transforms the original (possibly nonconvex) optimization problem into a sequence of quadratic optimization problems, and has been shown to converge under certain conditions when the original cost functional being minimized is strictly convex. We prove that our more general algorithm is globally convergent (i.e., converges to a local minimum from any initialization) under less restrictive conditions, even when the original cost functional is nonconvex. We apply this algorithm to tomographic reconstruction from limited-angle data by formulating the problem as one of regularized least-squares optimization. The results demonstrate that the constraint of piecewise smoothness, applied through the use of edge-preserving regularization, can provide excellent limited-angle tomographic reconstructions. Two edge-preserving regularizers-one convex, the other nonconvex-are used in numerous simulations to demonstrate the effectiveness of the algorithm under various limited-angle scenarios, and to explore how factors, such as the choice of error norm, angular sampling rate and amount of noise, affect the reconstruction quality and algorithm performance. These simulation results show that for this application, the nonconvex regularizer produces consistently superior results. 相似文献
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In the last decades, the classification of schemes of haematological malignancies have undergone considerable changes both in terms of modifications of previous concepts and of methodological approaches, in parallel with the acquisition of new information on the physiopathological and functional pattern of haemic cells and of their precursors both at the lymph node and bone marrow level. The cyto-morphological aspects of haemic were better defined and integrated by the application of cyto- and histochemical methods, which were subsequently supplemented by bioenzymatic and cytogenetic techniques, then by immunophenotypical studies and finally by biomolecular investigations. Through the use of monoclonal antibodies and the introduction both in research and routine diagnostic practice of multiparameter analysis techniques, it is now possible to correlate several cellular parameters, to identify clonality of malignant cells as well as their lineage assignment and maturation stage. Flow cytometry has become an important, rapid and objective method for the diagnosis of haematological neoplasias. In the present survey we have illustrated the different expression of surface, cytoplasmic and nuclear antigens in haematological malignancies, their correlation with the clinical course of the disease and their diagnostic and prognostic significance. 相似文献
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Borman Walter C.; Hanson Mary Ann; Oppler Scott H.; Pulakos Elaine D.; White Leonard A. 《Canadian Metallurgical Quarterly》1993,78(3):443
Explores the role of early supervisory experience and cognitive ability in 1st-line supervisor performance. Similar to the F. L. Schmidt et al (see record 1986-31441-001) study of nonsupervisors, this research tested structural models hypothesizing relationships among supervisory experience, cognitive ability, supervisory knowledge and proficiency, and performance ratings, using a sample of 570 2nd-tour soldiers. The Schmidt et al model with an additional ability?→?experience path provided the best fit. The significant ability?→?experience path was interpreted as indicating that demonstrated ability contributes to soldiers being given the opportunity to obtain supervisory experience. Experience had a greater impact on supervisor proficiency than on supervisor knowledge. Ability had a greater impact on supervisor knowledge than on proficiency. Discussion focuses on the personal characteristics that might be involved in being assigned supervisory responsibilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Albert Lamperti Alan Conger Leslie Delaney Marvin Sodicoff 《Drug development and industrial pharmacy》1994,20(12):1971-1989
ABSTRACT
Our transdermal permeation studies of radioprotectors in permeation-enhancing vehicles led us to hypothesize that radiation-induced hair loss could be reduced by topical application of radioprotectors. In the present study we used a hair regrowth assay in “plucked” mice to measure the radioprotective effectiveness of WR-1065, cysteine and TEMPOL when they were dissolved in a variety of vehicles, i.e., saline, dimethyl formamide (DMF), propylene glycol (PG), dimethyl sulfoxide (DMSO), ethanol. Protector effectiveness varied with radiation dose and vehicles. At 600 R, WR-1065 or cysteine, in any vehicle, reduced radiation-induced baldness scores; at 800 R, only WR-1065 in DMF and cysteine in saline, produced some protection. TEMPOL in ethanol produced protection at both the 600 and 800 R. Results suggest that suitably chosen topical application of protector/vehicle combinations can reduce radiation-induced hair loss. 相似文献
Our transdermal permeation studies of radioprotectors in permeation-enhancing vehicles led us to hypothesize that radiation-induced hair loss could be reduced by topical application of radioprotectors. In the present study we used a hair regrowth assay in “plucked” mice to measure the radioprotective effectiveness of WR-1065, cysteine and TEMPOL when they were dissolved in a variety of vehicles, i.e., saline, dimethyl formamide (DMF), propylene glycol (PG), dimethyl sulfoxide (DMSO), ethanol. Protector effectiveness varied with radiation dose and vehicles. At 600 R, WR-1065 or cysteine, in any vehicle, reduced radiation-induced baldness scores; at 800 R, only WR-1065 in DMF and cysteine in saline, produced some protection. TEMPOL in ethanol produced protection at both the 600 and 800 R. Results suggest that suitably chosen topical application of protector/vehicle combinations can reduce radiation-induced hair loss. 相似文献
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One reason for the limited attention to existential psychology in child treatment is the assumption that children are restricted in the amount of freedom and responsibility they can assume. However, current research on child development reveals that children actively influence their social and physical environment and hence begin from birth the process of self-determination. This article presents guidelines for implementing existential psychology with children derived from theoretical tenets and case study findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Elaine F. Becker 《乙烯基与添加剂工艺杂志》1996,2(4):321-325
The introduction of low-price color systems, both quality control and color formulation, has brought affordability and practicality to the medium and small plastics companies. While color systems today are faster, cheaper, more accurate, easier to use than ever before, they are not that much more successful at doing what they were designed to do than they were 25 years ago. The pitfalls of start-up and implementation and the people problems have changed very little and are still a major factor in determining the degree of success. This paper discusses the ramifications of who is chosen to implement the system, what their charter is, and the resources that they are given. Factors to be considered and creating the right environment when implementing a color system are discussed. Some suggestions for planning a successful start-up and installation are given. 相似文献