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1.
We consider the switchbox routing problem of two-terminal nets in the case when all thek nets lie on two adjacent sides of the rectangle. Our routing model is the standard two-layer model. We develop an optimal algorithm that routes all the nets whenever a routing exists. The routing obtained uses the fewest possible number of vias. A more general version of this problem (adjacent staircase) is also optimally solved.This research was supported in part by NSA Contract No. MDA-904-85H-0015, NSF Grant No. DCR-86-00378, and by NSF Engineering Research Centers Program NSFD CDR 88003012. 相似文献
2.
Contends, on the basis of posited social-role theory of gender and helping, that the male gender role fosters helping that is heroic and chivalrous, whereas the female gender role fosters helping that is nurturant and caring. In social psychological studies, helping behavior has mainly been examined in the context of short-term encounters with strangers. This focus has tended to exclude from the research literature those helping behaviors prescribed by the female gender role, because they are displayed primarily in long-term, close relationships. In contrast, the helping behaviors prescribed by the male gender role have been generously represented in research findings because they are displayed in relationships with strangers as well as in close relationships. Results from a meta-analytic review of sex differences in 172 studies (appended) in helping behavior indicate that in general men helped more than women and women received more help than men. Nevertheless, sex differences in helping were inconsistent across studies and were successfully predicted by various attributes of the studies and the helping behaviors. (96 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
We examined the relations between sociotropy and autonomy and clinical features of depression. A. T. Beck (1983) proposed that sociotropy is related to a sense of deprivation and clinical features associated with reactive depression and that autonomy is related to a sense of defeat and clinical features associated with endogenous depression. C. J. Robins et al (see record 1989-19204-001) found support for the hypothesis for sociotropy but not for autonomy, and they suggested that the autonomy scale may be problematic. We administered new measures of sociotropy and autonomy and a more comprehensive assessment of clinical features to 50 unipolar depressed inpatients. The results support the selective relations of both sociotropy and autonomy to the predicted sets of clinical features. This study adds to the growing evidence that these personality dimensions are important to the understanding of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Toshiaki Nishihata Mayumi Ishizaka Sigeharu Yokohama Alice C. Martino Roger E. Gordon 《Drug development and industrial pharmacy》1993,19(20):2679-2698
The effects of particle size and food on the absolute bioavailability of U-78875 in dogs after oral administration of either a suspension or tablet dosage form were investigated. A reduction of particle size caused a significant increase in bioavailability along with an increase in dissolution rate. Additionally, both suspension and tablet dosage forms administered after food caused an increase in bioavailability. Thus, to accelerate drug dissolution, a reduction of U-78875 particle size from the unmilled state is important for the optimization of formulation compositions. To increase the bioavailability of U-78875, postprandial dosing should be considered. 相似文献
5.
Alice Nasner 《European Journal of Lipid Science and Technology》1985,87(12):477-481
Antioxidizing Properties of Lecithin In various storage trials with sunflower oil and lard the antioxidizing properties of crude soybean lecithin as well as of its alcohol soluble and alcohol insoluble fraction could be proved. The addition of a very small quantity of these phospholipids to the oil after the refining process (prior to this process crude oil contains approx. 2–3% lecithin) improves the stability of these oils. The antioxidizing properties of phospholipids depend on: 1. composition of phospholipids, 2. tocopherol content of the oil. In our trials the alcohol soluble fraction of soybean lecithin performed the best antioxidizing results in sunflower oil by adding not less than 1%. In lard the same effect could already be reached with 0.1% of this fraction. As shown before, lecithin with a special phospholipid composition has antioxidizing properties and its addition in small quantities is beneficial to increase the stability of oils and fats. In new Japanese literature soybean saponines are the most favoured antioxidizing agents. Our trials did not confirm the results of these publications. 相似文献
6.
The number R(4, 3, 3) is often presented as the unknown Ramsey number with the best chances of being found “soon”. Yet, its precise value has remained unknown for almost 50 years. This paper presents a methodology based on abstraction and symmetry breaking that applies to solve hard graph edge-coloring problems. The utility of this methodology is demonstrated by using it to compute the value R(4, 3, 3) = 30. Along the way it is required to first compute the previously unknown set \(\mathcal {R}(3,3,3;13)\) consisting of 78,892 Ramsey colorings. 相似文献
7.
Formal Specification and Quantitative Analysis of a Constellation of Navigation Satellites 下载免费PDF全文
Zhaoguang Peng Yu Lu Alice Miller Tingdi Zhao Chris Johnson 《Quality and Reliability Engineering International》2016,32(2):345-361
Navigation satellites are a core component of navigation satellite‐based systems such as Global Positioning System, Global Navigation Satellite System and Galileo, which provide location and timing information for a variety of uses. Such satellites are designed for operating on orbit to perform tasks and have lifetimes of 10 years or more. Reliability, availability and maintainability analysis of systems has been indispensable in the design phase of satellites in order to achieve minimum failures or to increase mean time between failures and thus to plan maintenance strategies, optimise reliability and maximise availability. In this paper, we present formal models of both a single satellite and a navigation satellite constellation and logical specification of their reliability, availability and maintainability properties, respectively. The probabilistic model checker PRISM has been used to perform automated analysis of these quantitative properties. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
Maxine M. Denniston Nancy D. Brener Laura Kann Danice K. Eaton Timothy McManus Tonja M. Kyle Alice M. Roberts Katherine H. Flint James G. Ross 《Computers in human behavior》2010
The Youth Risk Behavior Surveillance System (YRBSS) monitors priority health-risk behaviors among US high school students. To better understand the ramifications of changing the YRBSS from paper-and-pencil to Web administration, in 2008 the Centers for Disease Control and Prevention conducted a study comparing these two modes of administration. Eighty-five schools in 15 states agreed to participate in the study. Within each participating school, four classrooms of students in grades 9 or 10 were randomly assigned to complete the Youth Risk Behavior Survey questionnaire in one of four conditions (in-class paper-and-pencil, in-class Web without programmed skip patterns, in-class Web with programmed skip patterns, and “on your own” Web without programmed skip patterns). Findings included less missing data for the paper-and-pencil condition (1.5% vs. 5.3%, 4.4%, 6.4%; p < .001), less perceived privacy and anonymity among respondents for the in-class Web conditions, and a lower response rate for the “on your own” Web condition than for in-class administration by either mode (28.0% vs. 91.2%, 90.1%, 91.4%; p < .001). Although Web administration might be useful for some surveys, these findings do not favor the use of a Web survey for the YRBSS. 相似文献
9.
10.
This paper presents a formulation of the facilities block layout problem which explicitly considers uncertainty in material handling costs on a continuous scale by use of expected values and standard deviations of product forecasts. This formulation is solved using a genetic algorithm meta-heuristic with a flexible bay construct of the departments and total facility area. It is shown that depending on the attitude of the decision-maker towards uncertainty, the optimal design can change significantly. Furthermore, designs can be optimized directly for robustness over a range of uncertainty that is pre-specified by the user. This formulation offers a computationally tractable and intuitively appealing alternative to previous stochastic layout formulations that are based on discrete scenario probabilities. 相似文献