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81.
Media and professional interest in homelessness represent important sources of data that may be useful in understanding broader societal factors influencing this pressing social issue. The present study examined the volume and content of coverage of homelessness in four major newspapers and the professional literature indexed in PsycINFO over the past 30 years. Media coverage showed a steep increase during the mid-1980s, a steady decline throughout the late 1980s and into the 1990s, and a plateau since the mid-1990s. Professional coverage demonstrated a less pronounced and delayed pattern of growth, with no sign of decline during the past decade. Content analysis of 574 newspaper articles revealed a sympathetic focus on deinstitutionalization and other structural causes of homelessness during the period of increasing coverage in the mid-1980s, as well as positive media coverage in terms of an emphasis on critical programs and services during more recent years. Content analysis of 324 professional journal articles showed that deficits and deviant characteristics of homeless people were discussed to a significantly greater extent than the structural causes of homelessness over the entire 30-year time period. Possible interactions among media coverage, professional interest, public opinion, the prevalence of homelessness, and policy initiatives are discussed.  相似文献   
82.
Over the last few decades radio has becomeone of the primary means of mass communication in Latin America, able to reach euen the remotest rural populations because of the transistor. Colombia, where ninety-one percent of the homes in the seven largest cities have at least one radio, has also been heavily impacted by this modern technological phenomenon, Elssy Bonilla de Ramos focuses on radio advertising as a means of characterizing the relationship between radio and the Colombian economic sector. She argues that private companies who own most of the country's stations and networks influence programming and advertising in order to widely promote products which they produce. She believes that in many cases these products are not necessary to the consumers'well-being but are advertised in a way to make them more desirable. The authorgives a brief history of commercial radio in Colombia during the last fifty years, stating that early in its development programming underwent significant changes in order to capture an expanded audience. Comedy, sports, news, soap operas, classical and popular music, and quiz shows soon dominated the airways to the exclusion of programming that could play a role in the political, social and economic development of the country. She contends that industries that owned radio were intent on training for consumption and she uses a week's sample of programming and advertising to illustrate her point.  相似文献   
83.
In this study, we present findings of the Portuguese national prevalence study, “Aging and Violence,” the purpose of which was to estimate the prevalence of abuse and neglect of older people in family settings over a 12-month period and examine the relationship between abuse and sociodemographic and health characteristics. Through a telephone survey of a representative probability sample (N = 1,123), we evaluated 12 abusive behaviors and demographic data. Overall, 12.3% of older adults experienced elder abuse in family settings. The prevalence rates of specific types were as follows: psychological, 6.3%; financial, 6.3%; physical, 2.3%; neglect, 0.4%; and sexual, 0.2%. Logistic regression was employed to determine the relationship between abuse and covariates. The study suggests that education level, age, and functional status are significantly associated with abuse. Accurate estimates of the prevalence of elder abuse and understanding of victim and perpetrator characteristics are fundamental to designing effective strategies for prevention and intervention.  相似文献   
84.
This paper presents a new Metropolis-adjusted Langevin algorithm (MALA) that uses convex analysis to simulate efficiently from high-dimensional densities that are log-concave, a class of probability distributions that is widely used in modern high-dimensional statistics and data analysis. The method is based on a new first-order approximation for Langevin diffusions that exploits log-concavity to construct Markov chains with favourable convergence properties. This approximation is closely related to Moreau–Yoshida regularisations for convex functions and uses proximity mappings instead of gradient mappings to approximate the continuous-time process. The proposed method complements existing MALA methods in two ways. First, the method is shown to have very robust stability properties and to converge geometrically for many target densities for which other MALA are not geometric, or only if the step size is sufficiently small. Second, the method can be applied to high-dimensional target densities that are not continuously differentiable, a class of distributions that is increasingly used in image processing and machine learning and that is beyond the scope of existing MALA and HMC algorithms. To use this method it is necessary to compute or to approximate efficiently the proximity mappings of the logarithm of the target density. For several popular models, including many Bayesian models used in modern signal and image processing and machine learning, this can be achieved with convex optimisation algorithms and with approximations based on proximal splitting techniques, which can be implemented in parallel. The proposed method is demonstrated on two challenging high-dimensional and non-differentiable models related to image resolution enhancement and low-rank matrix estimation that are not well addressed by existing MCMC methodology.  相似文献   
85.
Companies are currently choosing to integrate logics and systems to achieve better solutions. These combinations also include companies striving to join the logic of material requirement planning (MRP) system with the systems of lean production. The purpose of this article was to design an MRP as part of the implementation of an enterprise resource planning (ERP) in a company that produces agricultural implements, which has used the lean production system since 1998. This proposal is based on the innovation theory, theory networks, lean production systems, ERP systems and the hybrid production systems, which use both components and MRP systems, as concepts of lean production systems. The analytical approach of innovation networks enables verification of the links and relationships among the companies and departments of the same corporation. The analysis begins with the MRP implementation project carried out in a Brazilian metallurgical company and follows through the operationalisation of the MRP project, until its production stabilisation. The main point is that the MRP system should help the company's operations with regard to its effective agility to respond in time to demand fluctuations, facilitating the creation process and controlling the branch offices in other countries that use components produced in the matrix, hence ensuring more accurate estimates of stockpiles. Consequently, it presents the enterprise knowledge development organisational modelling methodology in order to represent further models (goals, actors and resources, business rules, business process and concepts) that should be included in this MRP implementation process for the new configuration of the production system.  相似文献   
86.
In this article, we establish strong consistency of the ridge estimates using extended results for the strong consistency of the least squares estimates in multiple regression models which discard the usual assumption of null mean value for the errors and only requires them to be i.i.d. with absolute moment of order r (0 < r ? 1).  相似文献   
87.
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.  相似文献   
88.
The construction of some wider families of continuous distributions obtained recently has attracted applied statisticians due to the analytical facilities available for easy computation of special functions in programming software. We study some general mathematical properties of the log-gamma-generated (LGG) family defined by Amini, MirMostafaee, and Ahmadi (2014 Amini, M., S. M. T. K. MirMostafaee, and J. Ahmadi. 2014. Log-gamma-generated families of distributions. Statistics 48:91332.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]). It generalizes the gamma-generated class pioneered by Risti? and Balakrishnan (2012 Risti?, M. M., and N. Balakrishnan. 2012. The gamma exponentiated exponential distribution. Journal of Statistical Computation and Simulation 82:1191206.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]). We present some of its special models and derive explicit expressions for the ordinary and incomplete moments, generating and quantile functions, mean deviations, Bonferroni and Lorenz curves, Shannon entropy, Rényi entropy, reliability, and order statistics. Models in this family are compared with nested and non nested models. Further, we propose and study a new LGG family regression model. We demonstrate that the new regression model can be applied to censored data since it represents a parametric family of models and therefore can be used more effectively in the analysis of survival data. We prove that the proposed models can provide consistently better fits in some applications to real data sets.  相似文献   
89.
This paper investigates the relationship between country-risks (or conflicts) within countries and electricity production. The determinants of electricity production have been neglected in the literature that favours the relationship between energy consumption, growth and development, and despite of the major challenges on electricity supply systems. We empirically establish that weighted conflict index, as well as sub-items as anti-government demonstrations, government crises and riots negatively influence electricity production per capita, after controlling for income per capita. Country conflicts affect electricity production mostly in the long-run. Our results imply that conflicts may affect electricity production substantially and consequently the economy as a whole. Policy should emphasize the institutional framework to avoid conflicts within countries in order to secure electricity production.  相似文献   
90.
Systems engineering (SE) professionals strive to develop new techniques to enhance the value of contributions to multidisciplinary smart product design teams. Products and services designers challenge themselves to search beyond the traditional design concept of addressing the physical, social, and cognitive factors. This paper covers the application of embedded user-centered systems engineering design practices into work processes based on the ISO 13407 framework [20] to support smart systems and services design and development. As practitioners collaborate to investigate alternative smart product designs, they concentrate on creating valuable products which will enhance positive interaction. This paper capitalizes on the need to follow a user-centered SE approach to smart products design [4, 22]. Products and systems intelligence should embrace a positive approach to user-centered design while improving our understanding of usable value-adding, experience and extending our knowledge of what inspires others to design enjoyable services and products.  相似文献   
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