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61.
An analytical framework is presented to study the cost/benefit tradeoffs of alternative internal control scenarios designed to ensure quality of outputs from information systems. A mathematical model is used to evaluate the impact that various alternatives have on system performance and cost. The model can be used to compare the benefits gained from enhanced processing with those arising from more effective internal control procedures. Model variables under the control of system designers include placement and effectiveness of internal control procedures, cost and quality of processing activities, both manual and computerized, and cost and quality of correction procedures. The model incorporates a penalty cost incurred by failure to detect and correct errors. The analytical process is illustrated through application to a specific information system. 相似文献
62.
63.
AbstractThe purpose of this research is to help reduce tensions in supply chain social sustainability (SCSS) decisions by providing a common global, contextual definition of social sustainability. This exploratory study utilised an inductive structured interview method to capture SCSS concept meanings. Those interviewed are from, have lived, and worked in developed economies, emerging economies and the base of the pyramid (BOP) economies. The results present a new global baseline definition of SCSS to inform theory and practice by finding that SCSS meanings differ not only between the different levels of economic development, but also within the levels as well. Culture, community and whether basic human needs are met all weigh into perspectives of what this concept is and should entail; a broad, contingent definition is most appropriate moving forward for sustainability planning and execution. Further research with stakeholders in more countries and communities is needed to validate our proposal. 相似文献
64.
后现代主义教育视野下的师生观 总被引:1,自引:0,他引:1
吕耀中 《青岛科技大学学报(社会科学版)》2006,22(4):94-97
后现代主义(postmodernism)是20世纪后半叶在西方社会流行的一种哲学、文化思潮。它脱胎于信息化后工业社会。后现代教育思想作为整个后现代思潮的一部分,它强调个人选择和参与,崇尚创造性、差异性、多样性、不确定性和建构性,主张教师与学生之间应建立一种平等的对话关系。这对我国当前的教育研究及教育改革,尤其是课堂教学改革具有一定的指导意义。 相似文献
65.
It is commonly assumed that contractors are largely calculative, instrumental and self-interested in their relationship with organizations and interface with them accordingly (e.g. low corporate interest and emotional investment). This paper describes a survey involving 117 contractors (62 on 'permanent' agency contracts and 55 on 'temporary' agency contracts) and a comparable (age, job level/grade, years of work experience) group of 86 direct employees (on fixed-term contracts). The survey comprised measures of the psychological contract, of organizational identification, social (corporate) attraction, team spirit and intention to leave. The findings show that contractors are not inevitably 'emotionally' detached from their place of work, in some cases investing in it as much as direct company employees. While transactional (e.g. financial gain, instrumentality) exchange considerations were more salient among contractors than employees, this did not appear to preclude the development of a relational (e.g. corporate integration and long-term investment) contractual orientation. 'Team spirit' and 'organizational identification' predicted the development of relational contracts over and above contractual status. The findings and their management implications are discussed in terms of 'strategic partnership'. 相似文献
66.
Haoli Wang Xirong Xu Yuansheng Yang Kai Lü 《Journal of Combinatorial Optimization》2011,21(4):481-496
Let G=(V,E) be a graph without an isolated vertex. A set D⊆V(G) is a k
-distance paired dominating set of G if D is a k-distance dominating set of G and the induced subgraph 〈D〉 has a perfect matching. The minimum cardinality of a k-distance paired dominating set for graph G is the k
-distance paired domination number, denoted by γ
p
k
(G). In this paper, we determine the exact k-distance paired domination number of generalized Petersen graphs P(n,1) and P(n,2) for all k≥1. 相似文献
67.
Byung-Cheon Choi Joseph Y.-T. Leung Michael L. Pinedo 《Journal of Combinatorial Optimization》2011,22(4):797-818
We consider a generalization of the proportionate flow shop problem with the makespan objective. Each job has a processing
requirement and each machine has a characteristic value. In our case, we assume that the time a job occupies a machine is
equal to the processing requirement of the job plus a setup time that is equal to the characteristic value of that machine.
In this paper, we consider permutation schedules and show that the problem is solvable in polynomial time when the number
of machines is fixed. 相似文献
68.
Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 x 10(-4) (ppm coal tar in total diet) + 240 x 10(-4) (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 x 10(-4) (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10(-3) per microgram per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10(-3) per microgram per kg body weight per day listed in the U.S. EPA Integrated Risk Information System. 相似文献
69.
Christopher R. Kirman Sean M. Hays Gregory L. Kedderis Michael L. Gargas & Dale E. Strother 《Risk analysis》2000,20(1):135-152
Historically, U.S. regulators have derived cancer slope factors by using applied dose and tumor response data from a single key bioassay or by averaging the cancer slope factors of several key bioassays. Recent changes in U.S. Environmental Protection Agency (EPA) guidelines for cancer risk assessment have acknowledged the value of better use of mechanistic data and better dose–response characterization. However, agency guidelines may benefit from additional considerations presented in this paper. An exploratory study was conducted by using rat brain tumor data for acrylonitrile (AN) to investigate the use of physiologically based pharmacokinetic (PBPK) modeling along with pooling of dose–response data across routes of exposure as a means for improving carcinogen risk assessment methods. In this study, two contrasting assessments were conducted for AN-induced brain tumors in the rat on the basis of (1) the EPA's approach, the dose–response relationship was characterized by using administered dose/concentration for each of the key studies assessed individually; and (2) an analysis of the pooled data, the dose–response relationship was characterized by using PBPK-derived internal dose measures for a combined database of ten bioassays. The cancer potencies predicted for AN by the contrasting assessments are remarkably different (i.e., risk-specific doses differ by as much as two to four orders of magnitude), with the pooled data assessments yielding lower values. This result suggests that current carcinogen risk assessment practices overestimate AN cancer potency. This methodology should be equally applicable to other data-rich chemicals in identifying (1) a useful dose measure, (2) an appropriate dose–response model, (3) an acceptable point of departure, and (4) an appropriate method of extrapolation from the range of observation to the range of prediction when a chemical's mode of action remains uncertain. 相似文献
70.
R. C. L. Hemming 《Social Policy & Administration》1975,9(3):207-219
The purpose of this paper is firstly to investigate the distribution of two parent low income families in England and Wales and Scotland for see to what extent they differ, and secondly to examine the relative importance of certain contributing factors in determining the distributions. From an analysis of Family Expenditure Survey data it is found that although it is difficult to arrive at statistically verifiable conclusions about the nature of the distributions, interesting qualitative observations can be made. 相似文献