Is the scheduling task context-dependent? A survey investigating the presence of constraints in different manufacturing contexts

Abstract

Most studies regarding real scheduling constraints only consider the constraints related to the specific manufacturing environment studied, limiting the possibility of drawing general conclusions. A survey of 50 companies was conducted in order to discover which constraints were present and what their relationship was with the scheduling context. This paper investigates which practical scheduling constraints are present in the manufacturing industry and whether the scheduling task is context-dependent. Results of this study show that some practical production constraints are context-dependent.     

Internationaler Joint Venture Erfolg: Eine Meta-Analyse

To analyze the success factors of international joint ventures (IJVs), this study meta-analytically integrates 106 studies of 32.318 firms. The results show that the success factors from the partner level (e.g., operational and strategic fit, partner experience) and IJV level (e.g., commitment, trust, control, interdependence, conflicts, conflict management, and organizational learning) determine IJV performance. Further, results reveal that IJV type, industry, and geographical distance moderate the relationships between success factors and IJV performance. Thus, this study contributes to extant knowledge by synthesizing and contextualizing quantitative empirical IJV research.     

An extended Birnbaum–Saunders distribution: Theory,estimation, and applications

Abstract

Birnbaum and Saunders (1969a Birnbaum, Z.W., Saunders, S.C. (1969a). A new family of life distributions. J. Appl. Probab. 6:319–327.[Crossref], [Web of Science ®] , [Google Scholar]) pioneered a lifetime model which is commonly used in reliability studies. Based on this distribution, a new model called the gamma Birnbaum–Saunders distribution is proposed for describing fatigue life data. Several properties of the new distribution including explicit expressions for the ordinary and incomplete moments, generating and quantile functions, mean deviations, density function of the order statistics, and their moments are derived. We discuss the method of maximum likelihood and a Bayesian approach to estimate the model parameters. The superiority of the new model is illustrated by means of three failure real data sets. We also propose a new extended regression model based on the logarithm of the new distribution. The last model can be very useful to the analysis of real data and provide more realistic fits than other special regression models.     

An extension of the gamma distribution

ABSTRACT

The gamma distribution has been widely used in many research areas such as engineering and survival analysis. We present an extension of this distribution, called the Kummer beta gamma distribution, having greater flexibility to model scenarios involving skewed data. We derive analytical expressions for some mathematical quantities. The estimation of parameters is approached by the maximum likelihood method and Bayesian analysis. The likelihood ratio and formal goodness-of-fit tests are used to compare the presented distribution with some of its sub-models and non nested models. A real data set is used to illustrate the importance of the distribution.     

New Bootstrap Applications in Supervised Learning

Some bootstrap and boosting methods for problems related to classification are introduced in this article. The first method chooses better boosting weights by using a bootstrap search algorithm. The second method is a good way to define a classification frontier. A new formulation for boosting in linear discriminant analysis is given. Since in this new formulation the uncertainty is represented by the weighted covariance matrix, it is more appropriate from the conceptual point of view. Simulation results show that the proposed methods perform well in data analysis.     

Further evidence of automatic reinforcement effects on verbal form

The Analysis of Verbal Behavior - The form of a verbal response allows for reinforcement mediation and language transmission across cultures. Reinforcement, in turn, plays a decisive role in...     

A new destructive Poisson odd log-logistic generalized half-normal cure rate model

We propose a new cure rate survival model by assuming that the initial number of competing causes of the event of interest follows a Poisson distribution and the time to event has the odd log-logistic generalized half-normal distribution. This survival model describes a realistic interpretation for the biological mechanism of the event of interest. We estimate the model parameters using maximum likelihood. For different sample sizes, various simulation scenarios are performed. We propose the diagnostics and residual analysis to verify the model assumptions. The potentiality of the new cure rate model is illustrated by means of a real data.     

Mapping Civic Engagement in Later Life: A Scoping Review of Gerontological Definitions and Typology Proposal

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Research on older people’s civic engagement has increased significantly in the last two decades, as have policy and...     

Influence of form and timing of social support on parental outcomes of a child-maltreatment prevention program

This study examines how the form of social support (informal or formal) and the time frame at which it is provided (at the start or end of the program) influence parental outcomes on the “Apoyo Personal y Familiar” (APF) program for at-risk families showing inadequate child-rearing practices. A total of 496 parents participated, 247 parents referred by the municipal social services in the Autonomous Community of Castile and Leon (Spain), and 249 non-referred parents. Initial and final levels of use of and satisfaction with informal and formal support were used as predictors of change scores in self-rating measures of beliefs about child development, perceptions of the parental role and child-rearing practices, applying hierarchical linear regression analyses. Perceived use of and satisfaction with support explained around 22% to 49% of the change scores in the Nurturist belief as a simple view of child development, Couple agreement on educational matters, Permissive–neglectful practices and Coercion practices, after accounting for the variance due to risk status, financial situation and family structure variables. Informal support always has a positive impact irrespective of when the help is provided, whereas formal support only has a positive impact when applied at the start of the program. The adequate provision of social supports can be an efficient way to prevent child maltreatment by promoting changes in parental beliefs and practices related to at-risk parenting.