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41.
In this paper, we evaluate and quantify the energy losses associated with compressed‐air systems, and their costs to manufacturers. We also show how to reduce the cost of compressed air in existing facilities by making some modifications with attractive payback periods. Among the measures, we investigate to reduce the compressed air are: (1) repairing air leaks, (2) installing high‐efficiency motors, (3) reducing the average air inlet temperature by using outside air (4) reducing compressor air pressure. We also illustrate the potential saving associated with each measure by using realistic examples. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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In an attempt to expand understanding of more severe pathology, attachment theory, developed by John Bowlby, is applied to borderline personality disorder in adults. Conceptualized as a condition of profound insecure attachment, with extreme vacillations between a desire for proximity and attachment and a dread and avoidance of engagement, borderline pathology reflects traumatic attachment experiences, beginning early in life. Besides the importance of trauma, disturbances in affect regulation and cognitive distortions are emphasized. The secure base of a therapeutic bond provides consistency, reliability, and affirmation while encouraging exploration of separation and loss experiences, both current and past, in order to modify inner working models of oneself and relationships with others. Implications for prevention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
There complete 18S ribosomal RNA gene sequences from the rumen ciliates, Entodinium caudatum (1,639 bp), Epidinium caudatum (1,638 bp), and Polyplastron multivesiculatum (1,640 bp) were determined and confirmed in the opposite direction. Trees produced using maximum parsimony and distance-matrix methods (least squares and neighbour-joining), with strong bootstrap support, depict the rumen ciliates as a monophyletic group. Entodinium caudatum is the earliest branching rumen ciliate. However, Entodinium simplex does not pair with En. caudatum, but rather with Polyplastron multivesiculatum. Signature sequences for these rumen ciliates reveal that the published SSrRNA gene sequence from En. simplex is in fact a Polyplastron species. The free-living haptorian ciliates, The Loxophyllum, Homalozoon and Spathidium (Subclass Haptoria), are monophyletic and are the sister group to the rumen ciliates. The litostomes (Class Litostomatea), consisting of the haptorians and the rumen ciliates, are also a monophyletic group. 相似文献
44.
In children, recurrent cough is a common presenting symptom that may represent asthma. We tested the hypotheses that children with recurrent cough have increased cough-receptor sensitivity (CRS) or airway hyperresponsiveness (AHR). Skin prick testing, the capsaicin CRS test, and hypertonic saline (HS) challenge were performed in 44 children (median age: 8.9 yr) with recurrent dry cough (> or = 2 episodes of cough, each lasting > or = 2 wk, within a period of 12 mo) and 44 controls. Measures of CRS were the concentration of capsaicin required to stimulate > or = 2 coughs (Cth) and > or = 5 coughs (C5). During the coughing period, Cth (mean log: 0.62 [95% CI: 0.43 to 0.81]) and C5 (mean log: 1.15 [95% CI: 0.86 to 1.44]) of the subjects without AHR were significantly lower (p = 0.0026, 0.027, respectively) than Cth (mean log: 1.27 [95% CI: 0.88 to 1.66]) and C5 (mean log: 1.79 [95% CI: 1.21 to 2.37]) of the subjects with AHR and those of the controls (p = 0.0002 and 0.0001). During the cough-free period, there was no difference in CRS among the groups. In subjects who demonstrated AHR, the provocation dose causing a > or = 15% fall in FEV1 (PD15) during the cough period was significantly lower (p = 0.005) than that during the cough-free period. We conclude that AHR or increased CRS is present during the coughing phase in children with recurrent cough. 相似文献
45.
Gallagher-Thompson Dolores; Futterman Andrew; Hanley-Peterson Pat; Zeiss Antonette; Ironson Gail; Thompson Larry W. 《Canadian Metallurgical Quarterly》1992,60(2):300
Describes agreement among diagnoses made according to 5 definitions of endogenous depression in a sample of 99 depressed elders and discusses the relationship among these systems and selected demographic and clinical characteristics. Poor to fair agreement was generally demonstrated, except for Research Diagnostic Criteria (R. Spitzer et al, 1978) and Diagnostic and Statistical Manual of Mental Disorders-III—Revised (DSM-III—R), which demonstrated excellent agreement. Mostly, demographic and clinical variables (e.g., severity of depression) were unrelated to endogeneity diagnoses. The conclusion was reached that these criteria are not all measuring the same construct in older adults and that the relationship between depression severity and endogeneity should be discussed in terms of specific definitions rather than in general terms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Dominic Phelan Mark Reid Nicole Stanford Rian Dippenaar 《JOM Journal of the Minerals, Metals and Materials Society》2006,58(9):67-69
An in-situ laser-scanning confocal microscopy study has been undertaken on the phase transformations in highpurity titanium. Observations of the β-Ti to α-Ti were observed to proceed with a pronounced Widmanstätten plate morphology due to the large β-Ti grain size. An anomalous transformation was also observed, with the α-Ti growing with a defined ledge-like surface relief. The observed transformation morphologies are discussed with reference to the crystallography of the regions, analyzed using electron-backscatter diffraction. 相似文献
47.
Dinesh Chamund Bill Findlay Kevan Birkett Dynex Semiconductor Pat Wheeler Jon Clare Michael Bland 《电力电子》2005,3(3):40-44
双向IGBT模块是实现高频矩阵变换器极为有效的方法。略不同于硬开关PWM变换器,矩阵变换器中的开关和传导损耗取决于所选的调制策略。本文介绍了一种由诺丁汉大学推导的平均损耗的计算公式。测试一个使用1200V,200A的双向模块实现的三相到单相的构造,得到的波形说明了矩阵变换器的实际操作以及可能会出现的输出电流纹波。 相似文献
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