Operations research from the viewpoint of general systems theory

This paper examines the operations research process from the viewpoint of General Systems Theory. The components of the OR process and the relations between them are critically examined. The five components are: (1) the “reality” of the problem situation, (2) the conceptual model of the problem situation, (3) the scientific model of the conceptual model, (4) the solution to the scientific model, and (5) the implementation of the solution. The paper argues that we have sub-optimized both our knowledge (study) and our application of the OR process. That is, there have been extremely few studies and applications of OR which have concerned themselves with OR from a whole systems point of view. The paper argues that without a whole systems perspective OR can neither be understood nor effectively applied.     

Ethnic pride, biculturalism, and drug use norms of urban American Indian adolescents

This study examines how strength of ethnic identity, multiethnic identity, and other indicators of biculturalism relate to the drug use norms of urban American Indian middle school students. The article distinguishes categories of norms that may affect drug use. Regression analysis of self-reports by 434 American Indian seventh graders attending middle schools in a large southwestern U.S. city indicated that students who had a more intense sense of ethnic pride adhered more strongly to certain antidrug norms than those who did not. Whereas American Indian students with better grades in school held consistently stronger antidrug norms, there were few differences by gender, socioeconomic status, or age. These results have implications in social work practice for better understanding and strengthening the protective aspects of American Indian culture in drug prevention efforts.     

Exchange rate and wage policies in Central and Eastern Europe

After the eastern enlargement of the European Union (EU) and due to increasing labor market integration, wage determination in Central and Eastern Europe (CEE) has become a key issue in European economic policy making. In addition, a controversial discussion concerning the monetary integration of CEE countries into the EMU has emerged. Both issues have earned particular academic and political interest because Eastern and Western Europe are at different stages of economic development and volatile international capital flows seem to require either a higher degree of wage or exchange rate flexibility. Based on the Scandinavian model of wage adjustment by Lindbeck (1979), we analyze the role of exchange rates in the wage determination process of the Central and Eastern European countries to identify which exchange rate strategy contributes to faster wage convergence in Europe. Panel estimations suggest that workers in countries with fixed exchange rates are likely to benefit in the long run from higher wage increases.     

A Century of Nuptiality in Spain, 1900–2007

This article describes the annual evolution of nuptiality in Spain from the beginning of the last century up to the present day. The analysis is based on data on first marriages from population registration data (Movimiento Natural de Población) after various adjustment and estimation operations. This source has an advantage with respect to census data, since it allows us to follow the annual nuptiality fluctuations that are very sensitive to prevailing social and economic conditions. Over the long term, the phases of nuptiality in Spain are comparable to those observed in Western Europe. However, leaving aside the period disturbed by the Civil War (1936–1939), Spain does exhibit some particular features: a long interlude from 1940 to 1959 marked by late marriage, rooted in the long depression of the Spanish economy; a prolonged rise in nuptiality which lasted until the end of the 1970s, corresponding to the late arrival of the first oil shock in Spain; and finally, a certain delay in the decline of marriage, accompanied—since the early 2000s only—by a parallel diffusion of cohabitation. Last, Spain is converging with Europe in another aspect that is seldom taken into account. While, from 1950 to 1980, it was one of the few European countries to register a first marriage rate unfavourable to women, the reversal of this trend since the 1980s has brought Spain closer to the majority of its neighbours.     

Rural population and social security in Brazil: An analysis with emphasis on constitutional changes

This paper analyses the situation of the Brazilian rural population with respect to social insurance and social assistance at two points in time: 1988 and 1998. The 1988 Constitution defined new rules with regard to eligibility conditions and benefit values for the rural population. But it was only in July 1991, with Law 8213, that these changes were implemented. We compare — by gender and individual age — activity rates and probability of receiving benefits, before and after the changes in legislation. We also compare, at these two points in time, family structure and the importance of the income of older people in the family budget. The analysis makes clear the positive impact brought by the legislation on the coverage and per capita family income of those families with older members in rural Brazil, bringing about some degree of poverty alleviation, as well as bridging the gender gap with respect to access to benefits. In contrast to what occurs in other Latin American countries, nowadays the Brazilian rural population has almost universal access to social security benefits, not only at family level but also in individual terms.     

The use software ERGOSHOW in the education of health and safety at work to regardin the safety to children

It is believed that health and safety of workers should be worked with children and early teenagers, the perspective that adults are more aware of these issues by providing them with health and quality of life in their daily lives, this is want the ERGOSHOW. The choice of media means for transmitting content of Ergonomics, Health and Safety (OSH) is justified because of the great popularity of computer games are among the public of the study, thereby providing a greater assimilation of the content worked. Therefore, the aim of this study was to work with OSH issues related to children between 08 and 12 years old, city of, State of Minas Gerais, Brazil. To achieve this we used the software ERGOSHOW, quizzes, and lecture. One can see that the use of multimedia tools in the learning, especially when considering the reports of mothers according to the different behavior of children after the development of activities, such as parents in correcting posture in relation to computer use.     

Efficiency of personal protective equipment used in agriculture

Despite the practical importance of Personal Protective Equipment (PPE), both in production and in consumption, it is observed a main problem regarding the quality of many PPE?s used in Brazil. This study found a gap between the state of the art and the state of prevailing practices in the design of PPE?s, which main consequences affect the health of workers who use PPE in agriculture activities. The results of this study identified legal constraints of this occurrence, involving the validation of PPE designed for isolate agents, without the analysis of relevant activities and without prototypes experiments in more frequent use situation.     

A study of automotive workers anthropometric physical characteristics from Mexico Northwest

Due to the lack of anthropometric information in northwest Mexico, we did an anthropometric study that represents the population physical characteristics and that is reliable for the design or redesign of workstations. The study was divided in two phases. The first one was the anthropometric study of 2900 automotive industry workers in northwest of Mexico. The study includes 40 body dimensions of 2345 males and 555 females personalized to be used in future researches. Second phase includes compared anthropometric characteristics of population reported in four Mexican studies and a Colombian study against the current study. Benefits of this project are: a reliable database of anthropometric characteristic of automotive industry population for workstations design or redesign that match with the users, increase product quality and reduce economic, medical and union complains.     

Anthropometric data of adult wheelchair users for Mexican population

The aim of the study was to obtain anthropometric data of adult wheelchair users at Mexico. This study count with 108 disabled people (56 men and 52 women) using the wheelchair and having the upper extremities sufficiently efficient to perform professional activities. The subjects were aged 18-60. From the measurements obtained, it can be said that in each of these measures was observed that men have larger dimensions than women, except for body depth, in which women had a slightly greater difference. When comparing the data in this study against other studies it shows that there is a significant difference between the averages of these studies. Similar results were obtained when comparing our data against data of standard population. Anthropometric data obtained through this study appear to be the only of this kind in Mexico and showed significant differences between measures of disabled persons and standard persons. the use of these data may be helpful for the proper design of workstations designed for use by adults who use.     

Selection of a voice for a speech signal for personalized warnings: the effect of speaker's gender and voice pitch

There is an increasing interest in multimodal technology-based warnings, namely those conveying speech-warning statements. This type of warning may be tailored to the situation as well as to the target user's characteristics. However, more information is needed on how to design these warnings in a way that ensures intelligibility, promotes compliance and reduces the potential for annoyance. In this context, this paper reports an exploratory study whose main purpose was to assist the selection of a synthesized voice for a subsequent compliance study with personalized (i.e., using the person's name) technology-based warnings using Virtual Reality. Participants were requested to listen to speech signals, gathered from a speech synthesizer and post-processed in order to change the pitch perception, and then these were evaluated by fulfilling the MOS-X questionnaire. After that, the participants ranked the voices according to their preference. The effects of the speaker's gender and voice pitch, on both ratings and ranking were assessed. The preference of the male and female listeners for a talker's voice gender was also investigated. The results show that participants mostly prefer as first choice the high-pitched female voice, which also gathered the highest overall score in the MOS-X questionnaire. No significant influence of the participants' gender was found on the assessed measures.