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831.
To provide effective managerial support for decisions related to production planning and scheduling processes, it is useful to partition the set of decisions into a hierarchical framework. In the resulting system, higher level decisions impose constraints on lower level actions, and lower level decisions provide the necessary feed-back to reevaluate higher level actions. The purpose of this paper is to suggest optimum procedures to deal with the resulting subproblems and to analyze the interaction mechanisms among the different hierarchical levels. Computational results are given.  相似文献   
832.
This paper presents a comparison of two heuristic methods for assigning a part-time work force to meet varying daily work loads. The authors use actual operating data from Purdue National Bank, Lafayette, Indiana, to make teller staffing decisions. The performance criteria for comparison of the two heuristics is the minimum number of workers employed, minimum number of interbranch transfers, and computer time necessary to attain a solution.  相似文献   
833.
The purpose of the current study was to determine whether brand name can affect the public's evaluation of a product. All subjects smoked identical cigarettes. One group of subjects, however, knew the cigarettes by the name of “Frontiersman,” a masculine name, while the other group knew the cigarettes as “April,” a feminine name. Male and female subjects were asked to rate the cigarette on seven measures. Results show that women gave a more positive evaluation to the cigarette purportedly named “April,” while men gave a more positive evaluation to the identical cigarette when they thought it was named “Frontiersman.” In addition, women reacted more strongly than did men to brand name influence.  相似文献   
834.
A replication of the Alpert-Raiffa probability assessment experiment is used to motivate the development of several tests for evaluating assessors. The tests permit an evaluation of an assessor's accuracy in estimating target quantities and in estimating his own uncertainty as well. Assumption of normal subjective distributions permits the determination of subjective variances. Data from trial assessments are employed to test models which assert that assessed quantities are equal to subjectively assessed error variances. Several tests of the latter type are compared using data from individual, as well as pooled, assessors.  相似文献   
835.
近600年来我国的旱灾与瘟疫   总被引:6,自引:0,他引:6  
根据有关历史文献、气象资料、报表和地方志的统计结果 ,15— 19世纪 ,全国共发生旱灾 15次 ,总历时 4 9年 ,其中 14次有瘟疫伴生。北方旱灾 14次 ,13次有瘟疫伴生 ;南方旱灾 7次 ,均有瘟疫伴生 ,有 6次南北同旱。 2 0世纪 ,全国共发生旱灾 18次 ,其中 ,北方旱灾 17次 ,两次有瘟疫伴生 ;南方旱灾 11次 ,1次有瘟疫伴生。 2 0世纪的灾害发生率是前 5 0 0年的 6倍。该文指出 ,这是由于在全球工业化过程中 ,不断增加的温室气体产生了温室效应 ,使气候变暖、降水减少、持续冬暖所致。因此 ,该文建议加快实施西部开发 ,治理环境 ,实施节水、调水工程 ,提高防灾抗灾能力 ,以缓解南北旱灾和瘟疫的发生  相似文献   
836.
对西部林业生态环境建设资源配置方式的探讨   总被引:2,自引:0,他引:2  
资源配置的方式是西部林业生态环境建设的重要问题 ,它决定着资源的合理利用和效益大小 ,也影响着我国西部地区经济发展的进程。该文探讨了在西部大开发的背景下 ,在林业实施跨越式发展的形势所需下 ,西部所进行的林业生态环境建设 ,如何进行资源配置方式的选择。在分析了关于计划和市场两种资源配置方式的观点后 ,认为根据西部目前的现实状况 ,西部林业生态环境建设应实行计划和市场相结合的资源配置方式  相似文献   
837.
The UN Convention on the Rights of the Child mandates (Articles 19 and 20) that alternative care be available to protect children from maltreatment by parents and caregivers. Increasingly, countries around the world have recognized the benefits to child well-being of family-based care as an alternative to institutional care. The special if not extraordinary needs of children separated from parents because of abuse, neglect, and maltreatment and placed with foster families requires a commensurate effort to develop foster families who have special if not extraordinary skills. Methods that are effective and replicable across countries offer significant advantages, reducing investments in policies and practices that otherwise would have to be developed independently, country by country. This case study describes the factors that contributed to the transfer of knowledge in the assessment, selection, and training of foster parents and the impact to date.  相似文献   
838.
By building on a genetic‐inspired attribute‐based conceptual framework for safety risk analysis, we propose a novel approach to define, model, and simulate univariate and bivariate construction safety risk at the situational level. Our fully data‐driven techniques provide construction practitioners and academicians with an easy and automated way of getting valuable empirical insights from attribute‐based data extracted from unstructured textual injury reports. By applying our methodology on a data set of 814 injury reports, we first show the frequency‐magnitude distribution of construction safety risk to be very similar to that of many natural phenomena such as precipitation or earthquakes. Motivated by this observation, and drawing on state‐of‐the‐art techniques in hydroclimatology and insurance, we then introduce univariate and bivariate nonparametric stochastic safety risk generators based on kernel density estimators and copulas. These generators enable the user to produce large numbers of synthetic safety risk values faithful to the original data, allowing safety‐related decision making under uncertainty to be grounded on extensive empirical evidence. One of the implications of our study is that like natural phenomena, construction safety may benefit from being studied quantitatively by leveraging empirical data rather than strictly being approached through a managerial perspective using subjective data, which is the current industry standard. Finally, a side but interesting finding is that in our data set, attributes related to high energy levels (e.g., machinery, hazardous substance) and to human error (e.g., improper security of tools) emerge as strong risk shapers.  相似文献   
839.
840.
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