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41.
We say that a distribution over {0,1}n is (ε,k)-wise independent if its restriction to every k coordinates results in a distribution that is ε-close to the uniform distribution. A natural question regarding (ε,k)-wise independent distributions is how close they are to some k-wise independent distribution. We show that there exist (ε,k)-wise independent distributions whose statistical distance is at least nO(k)·ε from any k-wise independent distribution. In addition, we show that for any (ε,k)-wise independent distribution there exists some k-wise independent distribution, whose statistical distance is nO(k)·ε. 相似文献
42.
Hughes Rosemary B.; Nosek Margaret A.; Howland Carol A.; Groff Janet Y.; Mullen Patricia Dolan 《Canadian Metallurgical Quarterly》2003,48(3):182
Objective: To pilot test a health promotion intervention for women with physical disabilities. Design: Pre- and postintervention questionnaires. Participants: Two groups of women with physical disabilities (n=15). Intervention: Seven-session weekly workshop intervention grounded primarily in social-cognitive theory. Setting: Disability and rehabilitation settings. Main Outcome Measures: Indicators of health status. Results: Statistically significant positive changes between pre- and postintervention scores on measures of self-efficacy for dietary behaviors, medical decision making, social interaction, physical functioning, impact of physical limitation on role activities, and vitality. Conclusion: Women with disabilities who participate in this health promotion intervention may exhibit improvements on indicators of health status. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
The present study examined whether siblings experience marital conflict differently and whether such differences, if present, were associated with differences in their adjustment. Self-report data about marital conflict, children's depressed mood, behavioral conduct, and externalizing problems were obtained from 122 sibling pairs (mean ages = 10 and 12 years) and their parents. Results indicated that siblings were significantly different in exposure to and appraisals of marital conflict. Differences in siblings' exposure to marital conflict were significantly correlated with differences in their depressed mood, behavioral conduct, and externalizing problems. Differences in siblings' feelings of self-blame for marital conflict were significantly correlated with differences in their depressed mood and behavioral conduct. Children who experienced more marital conflict than their siblings had more adjustment problems than their siblings. These results highlight the importance of studying siblings' unique experiences of marital conflict to better understand its impact on children's adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Brody Gene H.; Ge Xiaojia; Kim Su Yeong; Murry Velma McBride; Simons Ronald L.; Gibbons Frederick X.; Gerrard Meg; Conger Rand D. 《Canadian Metallurgical Quarterly》2003,71(2):211
Data from 296 sibling pairs (mean ages 10 and 13 years), their primary caregivers, and census records were used to test the hypothesis that African American children's likelihood of developing conduct problems associated with harsh parenting, a lack of nurturant-involved parenting, and exposure to an older sibling's deviance-prone attitudes and behavior would be amplified among families residing in disadvantaged neighborhoods. A latent construct representing harsh-inconsistent parenting and low levels of nurturant-involved parenting was positively associated with younger siblings' conduct disorder symptoms, as were older siblings' problematic attitudes and behavior. These associations were strongest among families residing in the most disadvantaged neighborhoods. Future research and prevention programs should focus on the specific neighborhood processes associated with increased vulnerability for behavior problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Reviews the book, Depression in the medically ill: An integrated approach by G. Rodin, J. Craven, and C. Littlefield (see record 1991-97973-000). This book provides an in-depth coverage of current issues in the management of depression in the medically ill. The book is balanced in theoretical perspective and quite comprehensive in coverage of the empirical literature. The authors are well known to the area of depression and physical illness. The book is organized into three main sections dealing with 1) Clinical Presentation, 2) Etiology and Pathogenesis, and 3) Treatment. Numerous case examples are provided throughout to highlight different aspects of symptom presentation, diagnostic problems, and therapeutic management. Notably lacking from the review of prevalence studies is the work examining depression and chronic pain populations. In sum, Rodin et al. have drawn on a vast literature to provide a clear and coherent picture of the current state of knowledge and theory dealing with depression and medical illness. Their book joins a number of recent papers attempting to draw more attention to clinical issues in the management of depression in the medically ill. I would recommend the book to all clinicians who work with medically ill populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Louis Esperet 《Information Processing Letters》2007,101(5):215-219
A graph G is 2-outerplanar if it has a planar embedding such that the subgraph obtained by removing the vertices of the outer face is outerplanar. The oriented chromatic number of an oriented graph H is defined as the minimum order of an oriented graph H′ such that H has a homomorphism to H′. In this paper, we prove that 2-outerplanar graphs are 4-degenerate. We also show that oriented 2-outerplanar graphs have a homomorphism to the Paley tournament QR67, which implies that their (strong) oriented chromatic number is at most 67. 相似文献
47.
Three coupling strategies in matching the Ritz-Galerkin method and the finite element method are introduced for general elliptic equations, and useful numerical techniques are provided. Numerical experiments have been carried out for solving the typical, singular Motz problem, which shows that optimal convergence rates of numerical solutions can be achieved by using the combined methods and techniques provided in this paper. 相似文献
48.
We consider an integer-subset representation problem motivated by a medical application in radiation therapy. We prove NP-completeness, derive nontrivial bounds, and report on the performance of a greedy heuristic. 相似文献
49.
Ilkka Kuorinka Hannu Alaranta Ilkka Erich 《International Journal of Industrial Ergonomics》1995,15(6):437-446
During the years 1986–1989 The Finnish Work Environment Fund initiated a multicenter, intervention study (programme) to prevent musculoskeletal disorders at work. The programme consisted of four different projects comprising methodological, epidemiological, and interventive themes. The main results were as follows: (1) More than half of the occupational physiotherapists and physicians involved in the project felt that they did not have adequate training for testing the performance capacity of the musculoskeletal system. Several of the most commonly used musculoskeletal tests had either poor validity in predicting future musculoskeletal troubles or had poor reliability. (2) A controlled intervention study showed that active training of neck-shoulder muscles can prevent musculoskeletal troubles, even more than ergonomic actions. (3) It is possible to reduce sick-leave due to low-back disorders by intervention measures directed toward both the work (environment, tools) and the workers (working methods, positive attitude to work, preparedness to keep fit). (4) The identification of ergonomic hazards with the help of teamwork proved to be feasible. The practical improvements, however, were difficult to implement in the prevailing conditions. Some of the improvements increased the work load and the stress of the workers. This aspect needs further consideration. 相似文献
50.
白永忠 《石油化工安全环保技术》2002,18(4):5-7
分析了在役生产装置安全评价存在的职业卫生问题,提出了如何做好重点生产装置职业病预防工作的建议。 相似文献