The purpose of this paper is to present a selection of the most significant ANN (artificial neural network) applications used to solve PPC (production planning and control) problems. Therefore, the paper itself is a reasoned classification rather than a simple survey. The PPC domain is divided into various areas, and for each area one or more examples of ANNs are discussed, together with the benefits and drawbacks of their application to that particular area. Finally, two case studies developed by the authors are reported and discussed to analyse the main implementation problems to be considered when using ANNs. 相似文献
The purpose of this paper is to show in regression clustering how to choose the most relevant solutions, analyze their stability, and provide information about best combinations of optimal number of groups, restriction factor among the error variance across groups and level of trimming. The procedure is based on two steps. First we generalize the information criteria of constrained robust multivariate clustering to the case of clustering weighted models. Differently from the traditional approaches which are based on the choice of the best solution found minimizing an information criterion (i.e. BIC), we concentrate our attention on the so called optimal stable solutions. In the second step, using the monitoring approach, we select the best value of the trimming factor. Finally, we validate the solution using a confirmatory forward search approach. A motivating example based on a novel dataset concerning the European Union trade of face masks shows the limitations of the current existing procedures. The suggested approach is initially applied to a set of well known datasets in the literature of robust regression clustering. Then, we focus our attention on a set of international trade datasets and we provide a novel informative way of updating the subset in the random start approach. The Supplementary material, in the spirit of the Special Issue, deepens the analysis of trade data and compares the suggested approach with the existing ones available in the literature.
Every large management organization undergoes the cyclic progress of planning, programming, budgeting, and rating of work tasks of projects to be accomplished by priority in the light of resource constraints controlling personnel strenghts and operating funds by fiscal periods. This is true, especially of governmental departments that are commodity oriented. There must be some ultimate goal of fine grain visibility that management can attempt to achieve or at least approach in order for the functional directors within the organization structure to relate and report most readily to provide required data for proficient resource management. Two essential requirements are visibility and integrated reporting as herein prescribed. Following the ascertainment of resource requirements in the light of projected work effort, some logical procedure should be employed in the rationale of resource adjustments. The Tolerance Box technique is herein described. 相似文献
Low female labor market participation is a problem many developed countries have to face. Beside activating inactive women, one possible solution is to support the re-integration of unemployed women. Due to female-specific labor market constraints (preferences for flexible working hours, discrimination), this is a difficult task, and the question arises whether active labor market policies (ALMP) are an appropriate tool to help. It has been shown that the effectiveness of traditional (ALMP) programs—which focus on the integration in dependent (potentially inflexible) employment—is positive but limited. At the same time, recent evidence for Austria shows that these programs reduce fertility which might be judged unfavorable from a societal perspective. Promoting self-employment among unemployed women might therefore be a promising alternative. Starting their own business might give women more independence and flexibility to reconcile work and family and increase labor market participation. Based on long-term informative data, we find that start-up programs persistently integrate former unemployed women into the labor market, and the impact on fertility is less detrimental than for traditional ALMP programs. 相似文献
A good parametric spectral estimator requires an accurate estimate of the sum of AR coefficients, however a criterion which minimizes the innovation variance not necessarily yields the best spectral estimate. This paper develops an alternative information criterion considering the bias in the sum of the parameters for the autoregressive estimator of the spectral density at frequency zero. 相似文献
Although there has been growing attention to clients' expectations of career counseling, more research is necessary to clarify the role of these expectations in shaping client satisfaction at the end of the intervention. On the basis of expectation confirmation theory, this study examined the indirect effect of clients' initial expectations on overall satisfaction through the perceived performance and final confirmation of expectations. We also explored whether this indirect effect is dependent on counselors' initial expectations. Longitudinal data were collected on 83 counselor-client dyads involved in a career counseling intervention in northeast Italy. Results confirmed that clients' initial expectations predicted overall satisfaction with the intervention through the subsequent mediation of perceived performance and confirmation of clients' expectations. The moderating role of the counselors' initial expectations was not confirmed. These findings imply that career counselors should invest their efforts in managing clients' expectations. 相似文献
The link between language, communication and open discrimination has been the focus of numerous studies. For many years, language has been a vehicle of prejudice and negative stereotypes. However, in the last few years, overt verbal aggressions have diminished thanks to the implementation of equality policies and awareness-raising initiatives. Despite that, negative attitudes against protected groups might not have disappeared and may instead be transmitted subtly, such as through uncivil language. The goal of this research is to study the relation between language and subtle discrimination against lesbian and gay (LG) workers. With this goal in mind, 39 in-depth interviews were conducted. The analysis showed that LG people are victims of subtle discrimination and that language is one of the most common vehicles of prejudice and negative stereotypes. Jokes, inappropriate comments and questions are the expression of negative attitudes, which are probably present at an implicit level. Due to the ambiguity of these expressions and the settings where they have been studied — the workplace — these acts could be defined as uncivil behaviours. Practical implications, limitations and directions for future research are discussed. 相似文献
From the point of view of economic development, the world is far from being homogeneous. Among the possible causes of such uneven evolution, culture is starting to attract the attention of a growing number of scholars. The present paper surveys some of the most important contributions on culture and economics, with a particular focus on the definition and measurement of culture and on the impact of different cultural traits on economic variables. According to this review of the literature, cultures emphasising individual effort while providing equal opportunities for everyone are more likely to encourage sustained economic growth. 相似文献
ABSTRACTThis study describes the process of developing and validating the Sexual Prejudice in Sport Scale (SPSS), which is a multidimensional instrument developed to assess attitudes toward lesbians and gay men (LG) in sports. The authors conducted two studies: first, to establish the factor structure of the SPSS on 297 heterosexual athletes; and, second, to test the reliability and validity of the resulting 19-item scale on a sample of 311 heterosexual and 160 LG athletes. Exploratory factor analysis of an initial item pool yielded three factors: open rejection, which assesses the blatant prejudice expressed toward LG people; denial of visibility, which evaluates attitude toward the coming out of LG people; and gendering performance, which corresponds to gender stereotypes about performance/skills of LG people. A confirmatory factor analysis was conducted to assess the stability of the SPSS. The authors documented internal consistency, test-retest stability, and convergent/divergent validity. Implications and directions for future research are discussed. 相似文献