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61.
Industrial robots are increasingly used by many manufacturing firms. The number of robot manufacturers has also increased with many of these firms now offering a wide range of models. A potential user is thus faced with many options in both performance and cost. This paper proposes a decision model for the robot selection problem. The proposed model uses robust regression to identify, based on manufacturers' specifications, the robots that are the better performers for a given cost. Robust regression is used because it identifies and is resistant to the effects of outlying observations, key components in the proposed model. The robots selected by the model become candidates for testing to verify manufacturers' specifications. The model is tested on a real data set and an example is presented.  相似文献   
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Controversies about international migration expose the changing structure of and underlying assumptions about societal membership in many nations. The sociology of international migration has emerged as an increasingly important subfield over the past decade in large part because it has tended to move beyond more narrow economic and demographic problems and has begun to address this fundamentally sociological issue. In the future it will be particularly important that sociologists pay attention to how demographically changing societies define who is and is not a member. As such, legal status and the role of the state has become critically important.  相似文献   
65.
This article describes, theorizes and empirically investigates the concept of interactive profit-planning systems (PPS) through the lens of the dynamic capabilities logic. With this conceptualization: interactive PPS capabilities comprise budgeting, forecasting and results-reporting routines, in which top and middle managers interact to create knowledge for sensing, seizing, and business model reconfiguring (to manage strategic business change). Survey data from 331 Australian firms is analyzed employing partial least squares structural equation modeling. The data provides support for two hypotheses: (1) greater market turbulence strengthens the positive effect of interactive PPS capabilities on business unit performance; and (2) greater market turbulence strengthens the positive effect of flexibility values (of organizational culture) on interactive PPS capabilities. Our findings show that interactive PPS capabilities function according to the salient tenets of the dynamic capabilities logic, and clarify the beneficial roles of formal cybernetic control systems and the intertwined involvement of top and middle managers in using dynamic capabilities.  相似文献   
66.
Indigenous children and young people are over‐represented at all stages of the Australian child protection system. Policy and legislative initiatives exist in the state of Victoria, Australia aiming to support the connection between Indigenous children and young people in state care and their culture and community. This exploratory research involved focus group consultations with seven child and family welfare agencies to investigate the impacts, barriers, benefits and limitations of cultural support planning for Indigenous young people in, and leaving care in, Victoria. Findings indicated that cultural planning was of value when it could be completed. However, various shortcomings of current systems were identified including limited resourcing of Aboriginal Community Controlled Organisations to generate plans and provide direct and secondary consultation services to implement plans, difficulty gathering information for plans and some Indigenous young people expressing disinterest in connecting to their culture and community. Complexities in the relationships between the Indigenous and non‐Indigenous agencies that aimed to support Indigenous young people in care were also acknowledged. Participants identified a number of strategies to improve outcomes, such as facilitating better relationships between agencies, promoting opportunities for ongoing cultural training for staff in mainstream agencies and improving the resourcing of Aboriginal Community Controlled Organisations to deliver planning and to support cultural connections.  相似文献   
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Having an unintended birth is strongly associated with the likelihood of having later unintended births. We use detailed longitudinal data from the Add Health Study (N = 8300) to investigate whether a host of measured sociodemographic, personality, and psychosocial characteristics select women into this “trajectory” of unintended childbearing. While some measured characteristics and aspects of the unfolding life course are related to unintended childbearing, explicitly modeling these effects does not greatly attenuate the association of an unintended birth with a subsequent one. Next, we statistically control for unmeasured time-invariant covariates that affect all birth intervals, and again find that the association of an unintended birth with subsequent ones remains strong. This persistent, strong association may be the direct result of experiencing an earlier unintended birth. We propose several mechanisms that might explain this strong association.  相似文献   
68.
Erectile dysfunction (ED) is one of the most common disorders in male and is often associated with other age-related comorbidities. The aging process affects the structural organization and function of penile erectile components such as smooth muscle cell and vascular architecture. These modifications affect penile hemodynamics by impairing cavernosal smooth muscle cell relaxation, reducing penile elasticity, compliance and promoting fibrosis. This review aims to identify the mechanisms of ED in the penile aging process in experimental and clinical data. It also highlights areas that are in need of more research. The search strategies yielded total records screened from PubMed. Clarification of the molecular mechanisms that accompanies corpus cavernosum aging and aging-associated ED will aid new perspectives in the development of novel mechanism-based therapeutic approaches. Age is not a limiting factor for ED medical management, and it is never too late to treat. Hypogonadism should be managed regardless of age, and synergistic effects have been found during testosterone (T) replacement therapy when used along with oral phosphodiesterase-5 (PDE-5) inhibitors. Therefore, the clinical management of ED related to aging can be done by therapeutic interventions that include PDE-5 inhibitors, and other pharmacological treatments.  相似文献   
69.
Correlated data are commonly analyzed using models constructed using population-averaged generalized estimating equations (GEEs). The specification of a population-averaged GEE model includes selection of a structure describing the correlation of repeated measures. Accurate specification of this structure can improve efficiency, whereas the finite-sample estimation of nuisance correlation parameters can inflate the variances of regression parameter estimates. Therefore, correlation structure selection criteria should penalize, or account for, correlation parameter estimation. In this article, we compare recently proposed penalties in terms of their impacts on correlation structure selection and regression parameter estimation, and give practical considerations for data analysts. Supplementary materials for this article are available online.  相似文献   
70.
It is well known that in finance variances and covariances of asset returns move together over time. Recently, much interest has been aroused by an approach involving the use of the realized covariance (RCOV) matrix constructed from high-frequency returns as the ex-post realization of the covariance matrix of low-frequency returns. For the analysis of dynamics of RCOV matrices, we propose the generalized conditional autoregressive Wishart (GCAW) model. Both the noncentrality matrix and scale matrix of the Wishart distribution are driven by the lagged values of RCOV matrices, and represent two different sources of dynamics, respectively. The GCAW is a generalization of the existing models, and accounts for symmetry and positive definiteness of RCOV matrices without imposing any parametric restriction. Some important properties such as conditional moments, unconditional moments, and stationarity are discussed. Empirical examples including sequences of daily RCOV matrices from the New York Stock Exchange illustrate that our model outperforms the existing models in terms of model fitting and forecasting.  相似文献   
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