Minimization of maximum lateness under linear deterioration

This paper considers a single-machine scheduling problem to minimize the maximum lateness. The processing time of each job is a linear function of the time when the job starts processing. This problem is known to be -hard in the literature. In this paper, we design a branch-and-bound algorithm for deriving exact solutions by incorporating several properties concerning dominance relations and lower bounds. These properties produce synergic effects in accelerating the solution finding process such that the algorithm can solve problems of 100 jobs within 1 min on average. To compose approximate solutions, we revise a heuristic algorithm available in the literature and propose several hybrid variants. Numerical results evince that the proposed approaches are very effective in successfully reporting optimal solutions for most of the test cases.     

Learning organization,organizational culture,and affective commitment in Malaysia: A person–organization fit theory

ABSTRACT

Based on person–organization fit theory, this article moves beyond theories of motivation and social exchange relationships that have often been used in commitment literature. This article contributes to understanding perceptions of organizational culture (OC) and affective commitment (AC) through perceptions of a learning organization (LO). Such understanding helps to tackle current commitment issues in Malaysia through strategic human resources development (HRD) planning and deploying organization development activities. We examined: (a) the extent to which organizations with an embraced LO mediated OC and AC, (b) the most influential component of OC in promoting employee AC, and (c) the most important component of LO for influencing OC and AC. We obtained 516 respondents (64.5% response rate) in selected Malaysian private organizations. It was concluded that LO mediated the relationship between OC and AC. Respect for people was an influential factor of OC for AC, while empowerment played a significant role in LO culture mediating the relationship between OC and AC. HRD practitioners should strategically plan organizational activities, norms, and policies that promote organizational learning processes and a learning culture to enhance AC.     

Combining forward and backward mortality estimation

Demographers often form estimates by combining information from two data sources—a challenging problem when one or both data sources are incomplete. A classic example entails the construction of death probabilities, which requires death counts for the subpopulations under study and corresponding base population estimates. Approaches typically entail ‘back projection', as in Wrigley and Schofield's seminal analysis of historical English data, or ‘inverse’ or ‘forward projection’ as used by Lee in his important reanalysis of that work, both published in the 1980s. Our paper shows how forward and backward approaches can be optimally combined, using a generalized method of moments (GMM) framework. We apply the method to the estimation of death probabilities for relatively small subpopulations within the United States (men born 1930–39 by state of birth by birth cohort by race), combining data from vital statistics records and census samples.     

国际金融衍生品交易从监管到治理的演进研究

国际金融衍生品交易规模日益扩大及其对全球经济的影响引起学者们的普遍关注.本文区分治理机制的不同发展阶段,构建了监管向治理演进的模型.总结当前国际金融衍生品交易监管的理论和现状,提出治理机制多元性和互补性特点以及国际金融衍生品复杂性和多样性推动着监管机制必定向着更有效的治理机制演进,达到低成本的有效治理.有效治理的途径是各国国内监管制度的日趋完善、各国广泛的合作以及国际组织的治理.     

Variability in PAH-DNA Adduct Measurements in Peripheral Mononuclear Cells: Implications for Quantitative Cancer Risk Assessment

Biomarkers such as DNA adducts have significant potential to improve quantitative risk assessment by characterizing individual differences in metabolism of genotoxins and DNA repair and accounting for some of the factors that could affect interindividual variation in cancer risk. Inherent uncertainty in laboratory measurements and within-person variability of DNA adduct levels over time are putatively unrelated to cancer risk and should be subtracted from observed variation to better estimate interindividual variability of response to carcinogen exposure. A total of 41 volunteers, both smokers and nonsmokers, were asked to provide a peripheral blood sample every 3 weeks for several months in order to specifically assess intraindividual variability of polycyclic aromatic hydrocarbon (PAH)-DNA adduct levels. The intraindividual variance in PAH-DNA adduct levels, together with measurement uncertainty (laboratory variability and unaccounted for differences in exposure), constituted roughly 30% of the overall variance. An estimated 70% of the total variance was contributed by interindividual variability and is probably representative of the true biologic variability of response to carcinogenic exposure in lymphocytes. The estimated interindividual variability in DNA damage after subtracting intraindividual variability and measurement uncertainty was 24-fold. Inter-individual variance was higher (52-fold) in persons who constitutively lack the Glutathione S-Transferase M1 (GSTM1) gene which is important in the detoxification pathway of PAH. Risk assessment models that do not consider the variability of susceptibility to DNA damage following carcinogen exposure may underestimate risks to the general population, especially for those people who are most vulnerable.     

The hunt for a cure for Parkinson's disease

Several exciting new scientific advances have been made in the past decade toward both understanding the causes of and finding a cure for Parkinson's disease. Heartened by an acceleration in research findings in the past several years, the government has recently called for an infusion of funds from both the National Institutes of Health and private foundations into this burgeoning area of biomedical research. Most currently available conventional treatments for the disease only temporarily delay symptom presentation while doing nothing to halt disease progression. However, the rapidly accelerating pace of research in this field has left researchers hopeful that Parkinson's will be the first major age-related neurodegenerative disease for which we have a viable cure. In this article, advances in various areas of Parkinson's disease research are reviewed.     

Graphs with small balanced decomposition numbers

A balanced coloring of a graph \(G\) is an ordered pair \((R,B)\) of disjoint subsets \(R,B \subseteq V(G)\) with \(|R|=|B|\) . The balanced decomposition number  \(f(G)\) of a connected graph \(G\) is the minimum integer \(f\) such that for any balanced coloring \((R,B)\) of \(G\) there is a partition \(\mathcal{P}\) of \(V(G)\) such that \(S\) induces a connected subgraph with \(|S| \le f\) and \(|S \cap R| = |S \cap B|\) for \(S \in \mathcal{P}\) . This paper gives a short proof for the result by Fujita and Liu (2010) that a graph \(G\) of \(n\) vertices has \(f(G)=3\) if and only if \(G\) is \(\lfloor \frac{n}{2} \rfloor \) -connected but is not a complete graph.     

BAYESIAN ANALYSIS OF THE ADDITIVE MIXED MODEL FOR RANDOMIZED BLOCK DESIGNS

This paper deals with the Bayesian analysis of the additive mixed model experiments. Consider b randomly chosen subjects who respond once to each of t treatments. The subjects are treated as random effects and the treatment effects are fixed. Suppose that some prior information is available, thus motivating a Bayesian analysis. The Bayesian computation, however, can be difficult in this situation, especially when a large number of treatments is involved. Three computational methods are suggested to perform the analysis. The exact posterior density of any parameter of interest can be simulated based on random realizations taken from a restricted multivariate t distribution. The density can also be simulated using Markov chain Monte Carlo methods. The simulated density is accurate when a large number of random realizations is taken. However, it may take substantial amount of computer time when many treatments are involved. An alternative Laplacian approximation is discussed. The Laplacian method produces smooth and very accurate approximates to posterior densities, and takes only seconds of computer time. An example of a pipeline cracks experiment is used to illustrate the Bayesian approaches and the computational methods.     

A time-varying weights tuning method of the double EWMA controller

In recent years, the exponential-weighted-moving-average (EWMA) statistic based controllers are popular in semiconductor manufacturing. However, the single EWMA controller is not sufficient for compensating for the wear-out process. Thus, a double EWMA controller was proposed to enhance the capability for controlling the drifting process. In the literatures, in the solution of the double EWMA controller, only the “trade-off” solution weights are used to tune the controller. However, it is a fixed weight tuning method, and it is known that a time-varying weight will produce a superior performance over that of a fixed one (J. Quality Technol. 29 (1997) 184). Therefore, this study aims to develop a heuristic time-varying weights tuning method for the double EWMA controller. The numerical results showed that the proposed time-varying tuning method possesses an improvement of least 10% over that of the fixed weight scheme.