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41.
The purpose of this paper is to examine a type of resource allocation problem arising in the context of research and development activities. The particular problem analyzed involves scheduling a group of projects in such a way that total cost is minimized while several precedence relations are satisfied and specific completion times are maintained. The primary difficulty results from the existence of commonalities that allow the successful completion of a particular project to be applied to several different purposes. A solution approach is developed which combines a one-pass network algorithm to deal with the precedence and time restrictions and a dynamic programming procedure to allocate the resources to each project. 相似文献
42.
Turnover turned over: an expanded and positive perspective 总被引:4,自引:0,他引:4
The negative impact of turnover is well documented in the literature. This paper examines turnover with a unique, positive focus. Turnover is reviewed, not only from the standpoint of the organizational theorist, but with economic, sociological, and psychological/social psychological perspectives. Often ignored benefits of turnover are noted. 相似文献
43.
W. J. Chandler 《Long Range Planning》1978,11(6):14-20
This article outlines the methodology developed in the adoption of long range planning at Reed International. Whilst the author rightly draws attention to the fact that the methodology described may not be applicable, or preferable, for all businesses it can give valuable lessons. Particularly, since Reed International is a highly diversified multi-national group of companies whose activities range from pulp and paper to publishing and building products, the difficulties of ensuring that plans are logically coherent, informative and examine the relative range of alternatives, is a complex and difficult task. Therefore, the paper provides a highly relevant and detailed insight into the planning methodology adopted by a company whose activities are wide ranging both in terms of product mix and geographical location. The author stresses the importance of planning as a process which includes the necessary structural underpinning but which concentrates essentially on the integration of concepts and ideas which may help the future performance of the company. Finally, the author also examines the important but often forgotten element of planning, the elements of control necessary to ensure effective implementation. 相似文献
44.
W. B. Morley 《Long Range Planning》1986,19(6):124-129
This article describes the series of changes which British Telecom has gone through over the last 10 years or so— changes which have often been dramatic and highly publicized. Faced with the challenges of the fast-changing business environment of the past decade—the most obvious of which was the technological revolution—British Telecom was perceived to be safe and reliable, but slow to change and expensive. Its strengths were the widespread understanding and acceptance of the need for change, its reservoir of the necessary skills and talent, a sound commercial infrastructure and a corporate culture. The author describes the organizational changes which have taken place and looks to a future where change is endemic if a business is to survive. 相似文献
45.
R W Hart S C Freni D W Gaylor J R Gillette L K Lowry J M Ward E K Weisburger P Lepore A Turturro 《Risk analysis》1986,6(2):117-154
The Color Additives Scientific Review Panel considered whether there was information sufficient to perform a carcinogenic risk assessment on the colors D&C Red No. 19 (R-19), D&C Red No. 37 (R-37), D&C Orange No. 17 (O-17), D&C Red No. 9 (R-9), D&C Red No. 8 (R-8) and FD&C Red No. 3 (R-3) and to evaluate the assessments sent to FDA as part of the petitions for use of the colors for drug and external uses by the Cosmetic, Toiletry and Fragrance Association (CTFA). There is a lack of human data concerning the colors for making a human health assessment, so the assessments are based upon the extrapolation of animal data. The risk assessments are determined for exposure to single chemicals. Excluded from consideration are possible effects from exposure to multiple chemicals, such as co-carcinogenesis, promotion, synergism, antagonism, etc. In the light of recent efforts in establishing a consensus in risk assessment, the Panel has determined that the CTFA assessments for R-10, O-17, and R-9 are consistent with present acceptable usages, although it questions some of the assumptions used in the assessments. The Panel identified a number of general assumptions made, and discusses their validity, their impact on total uncertainty, and the potential options to address the gaps in understanding that necessitate the assumption. The Panel also derived revised risk estimates using more "reasonable" assumptions than "worst-case" situations, for 90th percentile and average exposure. For those assumptions that are easily quantifiable, the Panel's estimates are less than an order of magnitude lower than the CTFA risk estimates, indicating that the underestimates and overestimates of the CTFA risk estimates tend to balance each other. The impact of most of the assumptions is not quantifiable. The assessment for R-3 is complicated by the fact that there is no good skin penetrance study for this color. It was assumed that the penetrance is similar to that of another water-soluble xanthene color, R-19. It is expected that the absorption of the color is not likely to exceed that of the smaller molecule, R-19. Therefore, the risk estimates are similar to the CTFA estimates, but with different reasoning. The estimates for R-8 and R-37 are different from the others in that there is a lack of any exposure or toxicological information on these colors.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
46.
Strong, effective communication may be the single most important key to success for any type of executive. Leaders of health care organizations must be able to promote ideas that others will implement, help staff see the value of their work, and have the vision to overcome limitations that stand in the way of progress. 相似文献
47.
Koch JW 《Public opinion quarterly》2001,65(1):1-21
When candidates assume issue positions opposite those of their sponsoring political party do citizens recognize these positions? Relatedly, what role do candidates' actual issue positions play in citizens' perceptions of their issue positions? Examining citizens' perceptions of 1996 and 1998 House candidates' position on abortion, this research finds that citizens' perceptions are shaped largely by partisan and, to a lesser extent, gender stereotypes. However, candidates' individuating positions on abortion influence perceptions of the candidates' position, but the effects are considerably stronger for perceptions of Republican candidates. Democratic candidates are likely to adopt anti-abortion positions in districts characterized by lower than average levels of political awareness and education, reducing the likelihood their party-contradicting position is accurately perceived. In contrast, Republican candidates adopt a pro-choice position in districts characterized by high education and political awareness, increasing the likelihood their position is accurately perceived. 相似文献
48.
Clark HW 《Child welfare》2001,80(2):179-198
In FY 1993 and FY 1995, the federal government awarded 27 five-year grants that supported 35 residential treatment projects for substance-abusing pregnant and postpartum women and their children. These projects provided comprehensive culturally and gender-specific treatment. Preliminary aggregated data collected in a national cross-site evaluation of 24 of these projects are encouraging with respect to infant mortality and morbidity, treatment retention and completion rates, and behavioral changes in the participating mothers at six months postdischarge. Local evaluations reflect other benefits of treatment. Cost data are expected to demonstrate the efficiencies and benefits of these projects compared to no treatment. 相似文献
49.
This was a preliminary study to evaluate the effectiveness of a tobacco prevention program on knowledge, attitude, intention, and behavior of tobacco use among fourth-grade students in four north central Florida counties. The results suggest that the program was effective in improving students' knowledge, attitudes, and intention toward not using tobacco products. Data analysis showed that students in the education group had a greater improvement in knowledge than the comparison group. Students in the education group also improved their attitude and intention scores while the comparison group did not show any improvement. The results also indicated positive responses from the students. In addition, teachers also gave a very positive response to the program. 相似文献
50.
In an evaluation of prison-based residential drug treatment programs, the authors use three different regression-based approaches to estimating treatment effects. Two of the approaches, the instrumental variable and the Heckman approach, attempt to minimize selection bias as an explanation for treatment outcomes. Estimates from these approaches are compared with estimates from a regression in which treatment is represented by a dummy variable. The article discusses the advantage of using more than one method to increase confidence in findings when possible selection bias is a concern. Three-year outcome data for 2,315 federal inmates are used in analyses where the authors separately examine criminal recidivism and relapse to drug use for men and women. Statistical tests lead the authors to conclude that treatment reduces criminal recidivism and relapse to drug use. The treatment effect was largest when the inference was based on the Heckman approach, somewhat smaller when based on the instrumental variable approach, and smallest when based on the traditional dummy variable approach. Treatment effects for females were not statistically significant. 相似文献