David E. Burmaster 《Risk analysis》1998,18(1):33-35

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David S. Bushnell  William S. Cross 《Global Business and Organizational Excellence》1995,15(1):41-50

Federal Lands Highway (FLH), a unit of the federal Highway Administration, provides highway engineering services to federal land managing agencies to build America's scenic highways. Since 1988, FLH has been systematically implementing total quality management (TQM). A key component of that effort has been its partnering initiative. This has been used to reduce the traditional adversarial relationship between FLH and its contractors by allowing them to jointly discuss and reach mutual agreement on the overall goals of projects before disputes arise. Since costs are reduced and disputes avoided through such arrangements, partnering is a technique that all public-sector contract administrators should take under serious consideration.  相似文献   

    

David Lowry 《Global Business and Organizational Excellence》1995,14(2):57-66

Ford Electronics Manufacturing Corporation's Markham, Ontario, plant won the 1994 Shingo Prize for Manufacturing Excellence thanks to a comprehensive waste reduction program begun during the late 1980s. This article outlines the unique approach taken at the plant to implement its program, which concentrated on inventory management, floor space utilization, and employee empowerment.  相似文献   

    

Thomas A. Trikalinos  David C. Hoaglin  Kevin M. Small  Norma Terrin  Christopher H. Schmid 《Research Synthesis Methods》2014,5(4):294-312

Existing methods for meta‐analysis of diagnostic test accuracy focus primarily on a single index test. We propose models for the joint meta‐analysis of studies comparing multiple index tests on the same participants in paired designs. These models respect the grouping of data by studies, account for the within‐study correlation between the tests' true‐positive rates (TPRs) and between their false‐positive rates (FPRs) (induced because tests are applied to the same participants), and allow for between‐study correlations between TPRs and FPRs (such as those induced by threshold effects). We estimate models in the Bayesian setting. We demonstrate using a meta‐analysis of screening for Down syndrome with two tests: shortened humerus (arm bone), and shortened femur (thigh bone). Separate and joint meta‐analyses yielded similar TPR and FPR estimates. For example, the summary TPR for a shortened humerus was 35.3% (95% credible interval (CrI): 26.9, 41.8%) versus 37.9% (27.7, 50.3%) with joint versus separate meta‐analysis. Joint meta‐analysis is more efficient when calculating comparative accuracy: the difference in the summary TPRs was 0.0% (−8.9, 9.5%; TPR higher for shortened humerus) with joint versus 2.6% (−14.7, 19.8%) with separate meta‐analyses. Simulation and empirical analyses are needed to refine the role of the proposed methodology. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

    

David Crotty 《Serials Review》2014,40(3):141-146

Despite nearly 350 years of practice, we still do a fairly poor job of measuring the quality and impact of scholarly papers and the work of individual researchers. Much of our system for determining funding and career advancement revolves around one metric: the impact factor. Technology has progressed to a point where we can do better. We can now track the life of each individual paper after it has been published and better understand how it is read and how it is used. This creates a tremendous opportunity for new alternative metrics (“altmetrics”) to give us a much better sense of a paper's true impact. At the same time, we are now faced with an overwhelming quantity of information and seemingly unlimited ways to analyze a researcher's work. How do we separate out the digital needles from the haystack—the signal from the noise—and create useful tools for research assessment?  相似文献   

    

David Haziza  Christian‐Olivier Nambeu  Guillaume Chauvet 《Revue canadienne de statistique》2014,42(4):650-669

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David Han  H.K.T. Ng 《统计学通讯:理论与方法》2014,43(10-12):2384-2394

By running the life tests at higher stress levels than normal operating conditions, accelerated life testing quickly yields information on the lifetime distribution of a test unit. The lifetime at the design stress is then estimated through extrapolation using a regression model. In constant-stress testing, a unit is tested at a fixed stress level until failure or the termination time point of the test, while step-stress testing allows the experimenter to gradually increase the stress levels at some pre-fixed time points during the test. In this article, the optimal k-level constant-stress and step-stress accelerated life tests are compared for the exponential failure data under Type-I censoring. The objective is to quantify the advantage of using the step-stress testing relative to the constant-stress one. A log-linear relationship between the mean lifetime parameter and stress level is assumed and the cumulative exposure model holds for the effect of changing stress in step-stress testing. The optimal design point is then determined under C-optimality, D-optimality, and A-optimality criteria. The efficiency of step-stress testing compared to constant-stress testing is discussed in terms of the ratio of optimal objective functions based on the information matrix.  相似文献   

    

Diane P. Bischak  David J. Robb  Edward A. Silver  Joseph D. Blackburn 《Production and Operations Management》2014,23(5):762-772

In this article, we investigate the (R, S) periodic review, order‐up‐to level inventory control system with stochastic demand and variable leadtimes. Variable leadtimes can lead to order crossover, in which some orders arrive out of sequence. Most theoretical studies of order‐up‐to inventory systems under variable leadtimes assume that crossovers do not occur and, in so doing, overestimate the standard deviation of the realized leadtime distribution and prescribe policies that can inflate inventory costs. We develop a new analytic model of the expected costs associated with this system, making use of a novel approximation of the realized (reduced) leadtime standard deviation resulting from order crossovers. Extensive experimentation through simulation shows that our model closely approximates the true expected cost and can be used to find values of R and S that provide an expected cost close to the minimum cost. Taking account of, as opposed to ignoring, crossovers leads, on average, to substantial improvements in accuracy and significant cost reductions. Our results are particularly useful for managers seeking to reduce inventory costs in supply chains with variable leadtimes.  相似文献   

    

David Klang  Maria Wallnöfer  Fredrik Hacklin 《国际管理评论杂志》2014,16(4):454-478

The business model has become a popular concept in business and management fields. Yet, it is suffering from a paradox between outstanding popularity and severe criticism, which appears to impede the positive development of the scholarly discourse on the business model concept. Against this background, the purpose of this study is to provide insight into the antecedents of this paradox and to understand their implications for the future development of the concept. The following contributions are made. First, the authors apply a narrative approach to recognizing and interpreting the paradox, and introduce the analysis of syntactics of scholarly discourse as a novel method of investigating management concepts. Second, as a result of elaborating on recurrent themes and tensions in scholarly discourse, the authors extend the literature on business models through theorizing on the core of the concept along the dimensions of classification, constitution and configuration. In particular, they identify the simultaneity of separation and attachment as the main antecedent of the business model paradox. Third, the authors offer implications for further advancing the development of this management concept, and highlight the need for spurring integrative research while at the same time maintaining a plurality of perspectives.  相似文献   

    

Milo Nelson 《Serials Review》2013,39(2):5-10

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