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851.
Electrical systems can be categorized as critical systems where failure can result in significant financial loss, injury or threats to human life. The operators of the electric power control centers perform an activity in a specialized environment and have to carry it out by mobilizing knowledge and reasoning to which they have adequate training under the terms of the existing rules. To reach this there is a common mental request of personnel involved in these centers due the need to maintain attention, memory and reasoning request. In this sense, this study aims to evaluate the Mental Workload of technical workers of the Control Centers of Electrical Energy. It was undertaken a research on operators control centers of the electricity sector in Northeast Brazil. It was used for systematic observations, followed by interview and application of the instrument National Aeronautics and Space Administration Task Load Index known as NASA-TLX. As a result there will be subsidies for an assessment of mental workload of operators, and a contribution to improving the processes of managing the operation of electric utilities and the quality of workers.  相似文献   
852.
The aim of this paper is to measure the effectiveness of the organizations Information and Communication Technology (ICT) from the point of view of the manager, using Item Response Theory (IRT). There is a need to verify the effectiveness of these organizations which are normally associated to complex, dynamic, and competitive environments. In academic literature, there is disagreement surrounding the concept of organizational effectiveness and its measurement. A construct was elaborated based on dimensions of effectiveness towards the construction of the items of the questionnaire which submitted to specialists for evaluation. It demonstrated itself to be viable in measuring organizational effectiveness of ICT companies under the point of view of a manager through using Two-Parameter Logistic Model (2PLM) of the IRT. This modeling permits us to evaluate the quality and property of each item placed within a single scale: items and respondents, which is not possible when using other similar tools.  相似文献   
853.
The electronic ballot box has played a significant role in the consolidation of Brazilian political process. It has enabled paper ballots extinction as a support for the elector's vote as well as for voting counting processes. It is also widely known that election automation has decisively collaborated to the legitimization of Brazilian democracy, getting rid of doubts about the winning candidates. In 1995, when the project was conceived, it represented a compromise solution, balancing technical efficiency and costs trade-offs. However, this architecture currently limits the ergonomic enhancements to the device operation, transportation, maintenance and storage. Nowadays are available in the market devices of reduced dimensions, based on novel computational architecture, namely tablet computers, which emphasizes usability, autonomy, portability, security and low power consumption. Therefore, the proposal under discussion is the replacement of the current electronic ballot boxes for tablet-based devices to improve the ergonomics aspects of the Brazilian voting process. These devices offer a plethora of integrated features (e.g., capacitive touchscreen, speakers, microphone) that enable highly usable and simple user interfaces, in addition to enhancing the voting process security mechanisms. Finally, their operational systems features allow for the development of highly secure applications, suitable to the requirements of a voting process.  相似文献   
854.
The process of product development has received special attention as it is being recognized as a source of competitive gain. Through its systematic use companies reduce costs, increase quality and decrease development time. However, one can find products being launched on the market that cause dissatisfaction to its users, and in consequence if the customer feels harmed or injured he will no longer purchase a product from the same brand. This in regard only to the commercial aspect; usually the danger of an accident or injury is not even thought about. This paper is the basis of the dissertation master's degree and used a literature research to build the repertoire, analyzing the methodologies applied by product design engineers, designers and ergonomists. The analysis results demonstrate the inefficiency of the design methodologies ergonomic issues. The contribution of this work lies in the suggestion to include ergonomic tools in all phases of product development and the presentation of a table with the tools that points out its most suitable time of application and results.  相似文献   
855.
The study was performed in a sample of 39 firemen. The state of health for each fire fighter was evaluated by means of a clinical examination and also through some specific exams. Aerobic capacity was estimated as an indicator of physical fitness. In each load, cardiac frequency and oxygen consumption were measured under a steady state condition. Additionally, body composition was calculated using a Tanita professional scale. Physical effort at work was determined by measuring cardiac frequency using a telemetric unit. Evaluations were carried out during night shifts, registering information under the following conditions: night shifts without emergency, fire simulation, training exercises and real fire fighting. In general terms, it is possible to state that fire fighters are healthy according to the result of the clinical examination. However, it is very important to highlight that 70% of the firemen consume alcohol and 80% were smokers. The average aerobic capacity of the sample was 2.6 l/min or 34.5 ml/kg/min. In terms of overweight and obesity, the body mass index was 25.7, whereas the percentage fat mass reached an average of 22.9 %. The cardiovascular load in the night shifts without emergencies did not surpass 40%, which in Chile is considered the highest limit for sustained work. However, during training, simulations and real fires, the firemen had higher cardiac frequencies, reaching peak levels close to 100% cardiovascular load.  相似文献   
856.
Whether women's informal employment is an involuntary marginal condition or a preferred alternative to formal employment has generated intense debate in academic and policy circles, particularly in view of women's disproportionate representation in the informal economy. We analyzed detailed interviews with 136 working mothers in Mexico to gain a better understanding of the factors leading to informal employment, as well as the impact of this work on these women and their families. Our results show that informal employment was not a choice for many women who entered the informal labor market due to human capital constraints and family responsibilities. Additionally, women commonly faced challenges in meeting the needs of both their employers and their families and earning adequate income. We suggest policy options to address the factors constraining women's employment opportunities and improve the situation of those women already working in the informal economy.  相似文献   
857.
858.
In a construction project, the ‘production planning and control’ function drives the deployment of construction operations. A reliable function is therefore essential. Currently, this function is supplied using economic/contractual and production processes. This approach, however, disregards the explicit regulation of teams, meetings, and the linkages between the function’s elements. Using Lean Management and Complexity theories, we studied a mechanism to address this issue. Using data from an 18-storey building construction project in a case study, this paper analyses a prototype system for driving the function using their linkages. A questionable behaviour beyond the function’s capability was found. This behaviour involves complex, flexible, and push features, focused on execution, where the linkages driven by teams, meetings and processes cause variation from 10% up to 54% in the failure reasons, the progress, and the reliability. These findings suggest a function driven by its complexity level. These new insights require further study.  相似文献   
859.
Social Indicators Research - This paper proposes a National Corporate Social Responsibility Practices Index (NCSRPI) that determines the level of penetration of corporate social responsibility...  相似文献   
860.
Nest predation is an important ecological driver that can mold avian communities. Previous studies performed in urban areas support both predatory relaxation and increases when assessing natural and artificial nest predation. In this study, we assessed artificial nest predation pressure in a neotropical city considering spatial and habitat traits. Our results show that artificial nest predation was driven by the interaction between location and urbanization intensity, with visual predators being responsible for most predation. This supports the notion that urban areas can act as landscape entities that filter biodiversity. Our study, showing both predation relaxation and intensification in the same urban system, suggests that nest predation dynamics can be diverse throughout urban areas. Thus, the predation paradox can occur in parallel with scenarios in which rises in predator numbers can actually decrease nest survivorship. Future studies investigating nest predation in urban areas should take into account the spatial environmental heterogeneity of their system in order to fully capture the patterns and biases related to nest predation.  相似文献   
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