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Forecasts from dynamic factor models potentially benefit from refining the data set by eliminating uninformative series. This paper proposes to use prediction weights as provided by the factor model itself for this purpose. Monte Carlo simulations and an empirical application to short-term forecasts of euro area, German, and French GDP growth from unbalanced monthly data suggest that both prediction weights and least angle regressions result in improved nowcasts. Overall, prediction weights provide yet more robust results.

This study aims to present the climate change effect on potential evapotranspiration (ETP) in future periods.

Daily minimum and maximum temperature, solar radiation and precipitation weather parameters have been downscaled by global circulation model (GCM) and Lars-WG outputs. Weather data have been estimated according to the Had-CM3 GCM and by A1B, A2 and B1 scenarios in three periods: 2011-2030, 2045-2046 and 2080-2099. To select the more suitable method for ETP estimation, the Hargreaves-Samani (H-S) method and the Priestly–Taylor (P-T) method have been compared with the Penman-Monteith (P-M) method. Regarding the fact that the H-S method has been in better accordance with the P-M method, ETP in future periods has been estimated by this method for different scenarios.

In all five stations, in all three scenarios and in all three periods, ETP will increase. The highest ETP increase will occur in the A1B scenario and then in the A1 scenario. The lowest increase will occur in the B1 scenario. In the 2020 decade, the highest ETP increase in three scenarios will occur in Khorramabad and then Hamedan. Kermanshah, Sanandaj and Ilam stations come at third to fifth place, respectively, with a close increase in amount. In the 2050 decade, ETP increase percentages in all scenarios are close to each other in all the five stations. In the 2080 decade, ETP increase percentages in all scenarios will be close to each other in four stations, namely, Kermanshah, Sanandaj, Khorramabad and Hamedan, and Ilam station will have a higher increase compared with the other four stations.

Meanwhile, the highest ETP increase will occur in hot months of the year, which are significant with regard to irrigation and water resources.

Examines the debate over “Higher superstition” (Gross and Levitt, 1994). Puts forward the arguments in the book and the response to the book from members of the US science and technology studies community. Asserts that increases in technical control have been at the expense of social and individual control. Mentions “diversionary reframing” – changing the subject, possibly by diverting attention away from the subject matter to the person doing the criticizing. Explores public attitudes towards science and technology, quoting a number of layman approaches to the bafflement of science. Identifies the irony in Gross and Levitt’s arguments, particularly in developing the interface between science and technology. Recommends paying more attention to the social construction of beliefs.

Discusses US use of drug testing in the workplace, screening employees for smoking, AIDS, genetic traits and reproductive hazards. Attributes this to the costs employers face in insurance, litigation and compensation. Points out that the purpose of drug testing is to circumvent management responsibility for: accidents in the workplace, stress, bad management practices, and disregarding health and safety initiatives. Acknowledges that the tests are harmful and indefensible. Reports that 81 per cent of members of the American Management Association in 1996 conducted drug testing. Claims that screening is the alternative to monitoring – that is screening out individuals who are seen as high risk in some way – yet that misses the point – the focus should be on making hazardous working conditions safe. Indicates that companies may use drug testing as a means of deterring drug users from gravitating towards their organization. Mentions that workplace‐induced stress can lead to substance abuse and that, therefore it is management driven, rather than being a problem the worker brings to the workplace. Quotes a number of company physicians who object to policing drug use. Indicates that drug testing has diverted attention away from health and safety issues and hazardous working conditions.

Puts forward the limit to growth perspective, which is rarely mentioned in societies devoted to the increase of material living standards. Outlines the resources each individual in rich countries uses and extrapolates those figures to cover the rest of the world’s population, proving that it is clearly impossible to sustain such living standards. Criticizes profit maximization, market forces and the pursuit of business opportunities as inappropriate to the needs of the world’s poor majority. Explores how society could reduce its per capita resource use and environmental impact, particularly through the development of small scale self‐sufficient economies. Points out that most of the real economy would be in non‐cash areas. Hastens to mention that a simpler, less material and closer‐to‐nature lifestyle does not exclude information technology. Indicates that access to communal property and service needs to replace income as the means to a satisfying life. Summarizes how community gardens can be set up and the roles that community workers could play in saving towns.

Reports on a survey conducted to investigate acute respiratory infections (ARI) in children in developing countries, looking particularly at the Philippines. Explores the role of the National Committee for Acute Respiratory Infections and states its objectives and responsibilities. Asserts that state of health is associated with community structure, environmental factors, and social and psychological conditions. Finds also that maternal factors are important determinants in the incidence of ARI episodes, for example, the mother’s characteristics, level of health knowledge, her illness control activities, age, level of education, number of children, smoking behaviour, and the extent to which she has to fulfil other tasks. Explains the methodology used in the survey, the sampling procedure and research instruments used. Indicates that poor housing and living conditions should become the focal point of developmental efforts, and that better nipping in the bud health management should be encouraged through health education programmes.

The efficiency of the finite element analysis via force method depends on the overall flexibility matrix of the structure, while this matrix is directly affected from null bases vectors. As the null bases for an indeterminate structure are not unique, for an optimal analysis, the selected null bases should be sparse and banded corresponding to sparse, banded and well-conditioned flexibility matrix. This paper aims to present an efficient method for the formation of optimal flexibility matrix of finite element models comprising tetrahedron elements via mathematical optimization technique.

For this purpose, a linear mixed integer programming model is presented for finding sparse solution of underdetermined linear system, which is correspond to sparse null vector. The charged system search algorithm is improved and used to find the best generator for formation of null bases.

The efficiency of the present method is illustrated through some examples. The proposed method leads to highly sparse, banded and accurate null basis matrices. It makes an efficient force method feasible for the analysis of finite element model comprising tetrahedron elements.

The force method, in which the member forces are used as unknowns, can be appealing to engineers. The main problem in the application of the force method is the formation of a self-stress matrix corresponding to a sparse flexibility matrix. In this paper, the highly sparse, banded and accurate null basis matrices gains by using mathematical optimization technique.

A laboratory experiment explores the perceived fairness of hiring decisions with regards to justifications that might reduce the negative reactions of job recipients. In particular, we examine the effects of no justification, and the affirmative action argument on the perceived fairness of the hiring of women and minorities. Results indicate that the hiring decision is perceived to be fairer when no justification is given than when affirmative action is used to justify the decision. The perception of decision was further moderated by proportional values with stronger effects for men than women.

This paper presents the architecture of a system for robotic welding of complex tasks. The system integrates off‐line programming, control of redundant robots, collision‐free motion planning and sensor‐based control. An implementation for pipe structure welding made at Odense Steel Shipyard Ltd., Denmark, demonstrates the system can be used for automatic welding of complex products in one‐of‐a‐kind production.