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951.
A state-of-the-art review over fifty years of flow shop scheduling research, written by Gupta and Stafford (2006), comes to the conclusion that the mathematical theory of flow shop scheduling “suffers from too much abstraction and too little application”. In this paper we will develop an extended mathematical model for flow shop scheduling with parallel lines and simultaneously a worker assignment to machines as well as a solution concept for practical use. Such production systems are realized by applying the BTO-(Build to order) concept, as can be found in the automotive or computer industry, which allows customers to make any changes to their vehicles or hardware configuration within a few days before final assembly. In these cases late configuration is an important task for the producer and a complex scheduling problem arises in this context.  相似文献   
952.
The aim of this article is to show how research practices may simultaneously follow principles of children’s citizenship rights to participation and principles of protection and support when children exposed to violence are informants. The article focuses upon organisation of interview processes and interactions between adult researchers and child informants in interview encounters. We point to a number of ways in which one may negotiate the tensions between, on the one hand, victimised children’s vulnerability and dependence upon adults for protection and support, and on the other these children’s agency and rights to participation.  相似文献   
953.
Over recent decades, listening to children's voices and viewing children as competent actors has gathered momentum in research as well as in practice. Acknowledging children's perspectives requires sensitive listeners who are willing, deliberately and as realistically as possible, to reconstruct children's ways of seeing. In our study, based in Norway, we investigated the views of 22 adolescents in long‐term foster care and 15 of their birth parents and 21 of their foster parents. Using Q methodology, we explored congruence and incongruence in the perception of ‘family’ among foster parents, birth parents and their adolescent (foster) children. We found three family perspectives among the adolescents. Within two of these perspectives, there seem to be more congruent understandings of the children's perspectives among the parent groups. We discuss some main implications in light of these findings. In Norway, as in many other countries, the policy of child welfare is that children first and foremost should grow up with their birth family. When out‐of‐home placements are necessary, a basic principle is that children should remain in contact with their birth family.  相似文献   
954.
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956.
Sex-related homicides tend to arouse wide media coverage and thus raise the urgency to find the responsible offender. However, due to the low frequency of such crimes, domain knowledge lacks completeness. We have therefore accumulated a large data-set and apply several structural learning algorithms to the data in order to combine their results into a single general graphic model. The graphical model broadly presents a distinction between an offender and a situation-driven crime. A situation-driven crime may be characterised by, amongst others, an offender lacking preparation and typically attacking a known victim in familiar surroundings. On the other hand, offender-driven crimes may be identified by the high level of forensic awareness demonstrated by the offender and the sophisticated measures applied to control the victim. The prediction performance of the graphical model is evaluated via a model averaging approach on the outcome variable offender's age. The combined graph undercuts the error rate of the single algorithms and an appropriate threshold results in an error rate of less than 10%, which describes a promising level for an actual implementation by the police.  相似文献   
957.
Consider semi-competing risks data (two times to concurrent events are studied but only one of them is right-censored by the other one) where the link between the times Y and C to non-terminal and terminal events, respectively, is modeled by a family of Archimedean copulas. Moreover, both Y and C are submitted to an independent right censoring variable D. We propose to estimate the parameter of the copula and some resulting survival functions using a pseudo maximum likelihood approach. The main advantage of this procedure is that it extends to multidimensional parameters copulas. We perform simulations to study the behavior of our estimation procedure and its impact on other related estimators and we apply our method to real data coming from a study on the Hodgkin disease.  相似文献   
958.
In recent years, several attempts have been made to characterize the generalized Pareto distributions (GPD) based on the properties of order statistics and record values. In the present article, we give some characterization results on GPD based on order statistics and generalized order statistics. Some characterizations of uniform distribution based on expectation of some functions of order statistics are also given.  相似文献   
959.
ABSTRACT

Entropy-type integral functionals of densities are widely used in mathematical statistics, information theory, and computer science. Examples include measures of closeness between distributions (e.g., density power divergence) and uncertainty characteristics for a random variable (e.g., Rényi entropy). In this paper, we study U-statistic estimators for a class of such functionals. The estimators are based on ε-close vector observations in the corresponding independent and identically distributed samples. We prove asymptotic properties of the estimators (consistency and asymptotic normality) under mild integrability and smoothness conditions for the densities. The results can be applied in diverse problems in mathematical statistics and computer science (e.g., distribution identification problems, approximate matching for random databases, two-sample problems).  相似文献   
960.
In this paper the stochastic properties of two estimators of linear models, mixed and minimax, based on different types of prior information, are compared using quadratic risk as the criterion for superiority. A necessary and sufficient condition for the minimax estimator to be superior to the comparable mixed estimator is derived as well as a simpler necessary but not sufficient condition.  相似文献   
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