997 resultados para H120 Safety Engineering


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This work evaluates the feasibility of the draft-tube spouted bed for drying of herbal extract. Drying runs were carried out according to a central composite design in a conical-cylindrical draft-tube spouted bed. The variables studied were the percentage of the drying aid (ADJ), the drying gas flow rate relative to gas flow at minimum spouting (Q/Q(ms)), and the flow rate of extract fed to the system relative to the spouting gas flow rate W(s)/W(g)). Colloidal silicon dioxide was the drying aid used in order to improve drying performance. Statistical analysis of the effects of processing parameters on product recovery, product accumulation in the bed, and product properties permitted the identification of parameters presenting significant effects on drying. Optimized drying conditions were related to experimental parameters as follow: high levels of the percentage of drying adjuvant (ADJ), high airflow rate relative to minimum spouting (Q/Q(ms)), and low values of the feed flow rate of the extract relative to the gas flow rate (W(s)/W(g)).

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Les aportacions que es presenten en aquest llibre mostren els resultats de la investigació sobre el comportament humà en situacions d’emergència que s’ha dut a terme en el marc del projecte de recerca europeu BeSeCu. El projecte Be- SeCu —acrònim de Behaviour, Security and Culture (Comportament, Seguretat i Cultura)— forma part de la línia d’investigació i coneixement en matèria de seguretat del Setè Programa Marc de la Unió Europea. Concretament, el projecte es centra en una de les necessitats bàsiques establertes per la política europea en matèria de seguretat, com és la de conèixer en profunditat la realitat de les emergències a través de les persones que les han patit o dels professionals que hi treballen diàriament. Per assolir aquest objectiu, el projecte ha investigat les diferències i similituds del comportament humà en diferents situacions d’emergència i en diversos països europeus per tal de millorar els processos d’evacuació i protecció en aspectes com ara la comunicació, les indicacions i els procediments d’intervenció dels agents actuants. Les situacions d’emergències s’han investigat mitjançant dos actors clau, és a dir des de l’òptica de persones que han estat víctimes d’una situació d’emergència i des de l’òptica dels professionals dels serveis d’emergència. El grup principal d’estudi dels serveis d’emergència ha estat els cossos de bombers. La investigació del comportament humà, tant de víctimes com dels serveis d’emergència (cossos de bombers), s’ha centrat en cinc tipus diferents d’emergències: incendis d’habitatge, incendis en edificis públics, atemptats terroristes, terratrèmols i inundacions. El projecte estava format per un consorci d’institucions en què participaven un grup multidisciplinari de psicòlegs, sociòlegs, criminòlegs, enginyers i professionals de les emergències que treballen en escoles de bombers i policies, serveis d’emergència, centres de recerca i investigació i universitats de set països europeus: • Alemanya: Ernst-Moritz-Arndt Universität Greifswald, Department of Health and Prevention, Institute of Psychology (coordinació del projecte); • Alemanya: Hamburg Fire and Emergency Service Academy; • Espanya: Institut de Seguretat Pública de Catalunya, Unitat de Recerca de l’Escola de Policia i de l’Escola de Bombers; • Anglaterra: University of Greenwich, Fire Safety Engineering Group; • Itàlia: Università di Bologna, Gruppo di Ricerca in Psicologia dell’Emergenza; • República Txeca: Prague Psychiatric Centre; • Suècia: Man-Technology-Organisation; • Turquia: Association of Emergency Ambulance Physicians.

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There has been a rapid increase in the complexity and integration of many safety-critical systems. In consequence, it is becoming increasingly difficult to identify the causes of incidents and accidents back through the complex interactions that lead to an adverse event. At the same time, there is a growing appreciation of the need to consider a broad range of contextual factors in the aftermath of any mishap. A number of regulators, operators and research teams have responded to these developments by proposing novel techniques to support the analysis of complex, safety-critical incidents. It is important to illustrate these different approaches by applying them to a number of common case studies. The following pages, therefore, show how STAMP and AcciMap might support the Serviço Público Federal investigation into the explosion and fire of the Brazilian launch vehicle VLS-1 VO3. © 2006 Elsevier Ltd. All rights reserved.

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Introduction: The current Brazilian legislation states that health services must be performed by the Specialized Service of Safety Engineering and Labor Medicine (SESMT). Objective: To analyze the dental and medical reasons for absenteeism, checking the interference of factors such as age, gender and position of the worker, and most of the reasons that led the employee to miss work. Material and methods: The research appears as a descriptive study with a quantitative approach. The dental and medical certificates and statements of attendance were analyzed, duly approved, lodged in a acrylic industry in the city of Araçatuba-SP, from January to July 2011. Results: Of the total number of certificates (n = 1841), only 103 (5.6%) were for dental reasons. Predominance of the age group of 20-29 years, males and with non-administrative function. The reasons most dental and medical certificates stated that led the workers to miss working days were "inclusive and impacted teeth" and "diarrhea and gastroenteritis of presumed infectious origin", respectively. As to factors related to absenteeism, there was a severity index of 2.83, 1.33 frequency and average duration of absences of 2.12. Conclusions: It is concluded that dental reasons had little weight on total absences due to illness that caused the temporary leave of the worker for a shorter period. The age and function variables influence the occurrence of work absenteeism.

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Purpose - The purpose of this paper is to present a method to analyze the noise in aircraft cabins through the VHF Aeronautical Communication Channel, aimed at examining an environment that has the possibility of communication problems between the aircraft crew and the professionals responsible for the controls on land. Design/methodology/approach - This analysis includes equipment normally used for identification and comparison of electromagnetic noise, the cabin and the environment that are present in an airport, as well as equipment for frequency analysis and intensity of those signals. The analysis is done in a reverse way, eliminating situations that are not common in the examined environment, until the identification of the situation with the irregularity. Findings - According to the results, the implementation of the Fourier transform for noise analysis in the cabin was efficient. These results demonstrate that through this transformation, the noise sources can be identified in the environments in cases where there is much spectrum pollution. Research limitations/implications - This kind of noise analysis is important, considering the importance of having good accuracy in airport environment analysis. Originality/value - The paper presents the main trends in the future of aviation communications, and describes the new applications that aim to minimize problems with the current VHF channel.

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In this paper, the effects of uncertainty and expected costs of failure on optimum structural design are investigated, by comparing three distinct formulations of structural optimization problems. Deterministic Design Optimization (DDO) allows one the find the shape or configuration of a structure that is optimum in terms of mechanics, but the formulation grossly neglects parameter uncertainty and its effects on structural safety. Reliability-based Design Optimization (RBDO) has emerged as an alternative to properly model the safety-under-uncertainty part of the problem. With RBDO, one can ensure that a minimum (and measurable) level of safety is achieved by the optimum structure. However, results are dependent on the failure probabilities used as constraints in the analysis. Risk optimization (RO) increases the scope of the problem by addressing the compromising goals of economy and safety. This is accomplished by quantifying the monetary consequences of failure, as well as the costs associated with construction, operation and maintenance. RO yields the optimum topology and the optimum point of balance between economy and safety. Results are compared for some example problems. The broader RO solution is found first, and optimum results are used as constraints in DDO and RBDO. Results show that even when optimum safety coefficients are used as constraints in DDO, the formulation leads to configurations which respect these design constraints, reduce manufacturing costs but increase total expected costs (including expected costs of failure). When (optimum) system failure probability is used as a constraint in RBDO, this solution also reduces manufacturing costs but by increasing total expected costs. This happens when the costs associated with different failure modes are distinct. Hence, a general equivalence between the formulations cannot be established. Optimum structural design considering expected costs of failure cannot be controlled solely by safety factors nor by failure probability constraints, but will depend on actual structural configuration. (c) 2011 Elsevier Ltd. All rights reserved.

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In a study of Lunar and Mars settlement concepts, an analysis was made of fundamental design assumptions in five technical areas against a model list of occupational and environmental health concerns. The technical areas included the proposed science projects to be supported, habitat and construction issues, closed ecosystem issues, the "MMM" issues--mining, material-processing, and manufacturing, and the human elements of physiology, behavior and mission approach. Four major lessons were learned. First it is possible to relate public health concerns to complex technological development in a proactive design mode, which has the potential for long-term cost savings. Second, it became very apparent that prior to committing any nation or international group to spending the billions to start and complete a lunar settlement, over the next century, that a significantly different approach must be taken from those previously proposed, to solve the closed ecosystem and "MMM" problems. Third, it also appears that the health concerns and technology issues to be addressed for human exploration into space are fundamentally those to be solved for human habitation of the earth (as a closed ecosystem) in the 21st century. Finally, it is proposed that ecosystem design modeling must develop new tools, based on probabilistic models as a step up from closed circuit models. ^

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The biological safety profession has historically functioned within an environment based on recommended practices rather than regulations, so summary data on compliance or noncompliance with recommended practices is largely absent from the professional literature. The absence of safety performance outcome data is unfortunate since the concept of biosafety containment is based on a combination of facility based controls and workplace practices, and persistent failures in either type of controls could ultimately result in injury or death. In addition, the number of laboratories requiring biosafety containment is likely to grow significantly in the coming years in the wake of the terrorist events of 2001. In this study, the outcomes of 768 biosafety level 2 (BSL-2) safety surveys were analyzed for commonalities and trends. Items of non-compliance noted were classified as facility related or practice related. The most frequent item of noncompliance encountered was the failure to re-certify biosafety cabinetry. Not surprisingly, the preponderance of the other frequent items of non-compliance encountered were practice related, such as general housekeeping orderly, changes in compliance levels, as well as establish trends in the elements of items of non-compliance during the sequential survey period. The findings described in this study are significant because, for the first time, the outcomes of compliance with recommended biosafety practices can be characterized and thus used as the basis for focused interventions. Since biosafety is heavily reliant on adherence to specific safety practices, the ability to focus interventions on objectively identified practice-related items of non-compliance can assist in the reduction of worker risk in this area experiencing tremendous growth. The information described is also of heighten importance given the number of workplaces expected to involve potentially infectious agents in the coming years. ^

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The study aim was to determine whether using automated side loader (ASL) trucks in higher proportions compared to other types of trucks for residential waste collection results in lower injury rates (from all causes). The primary hypothesis was that the risk of injury to workers was lower for those who work with ASL trucks than for workers who work with other types of trucks used in residential waste collection. To test this hypothesis, data were collected from one of the nation’s largest companies in the solid waste management industry. Different local operating units (i.e. facilities) in the company used different types of trucks to varying degrees, which created a special opportunity to examine refuse collection injuries and illnesses and the risk reduction potential of ASL trucks.^ The study design was ecological and analyzed end-of-year data provided by the company for calendar year 2007. During 2007, there were a total of 345 facilities which provided residential services. Each facility represented one observation.^ The dependent variable – injury and illness rate, was defined as a facility’s total case incidence rate (TCIR) recorded in accordance with federal OSHA requirements for the year 2007. The TCIR is the rate of total recordable injury and illness cases per 100 full-time workers. The independent variable, percent of ASL trucks, was calculated by dividing the number of ASL trucks by the total number of residential trucks at each facility.^ Multiple linear regression models were estimated for the impact of the percent of ASL trucks on TCIR per facility. Adjusted analyses included three covariates: median number of hours worked per week for residential workers; median number of months of work experience for residential workers; and median age of residential workers. All analyses were performed with the statistical software, Stata IC (version 11.0).^ The analyses included three approaches to classifying exposure, percent of ASL trucks. The first approach included two levels of exposure: (1) 0% and (2) >0 - <100%. The second approach included three levels of exposure: (1) 0%, (2) ≥ 1 - < 100%, and (3) 100%. The third approach included six levels of exposure to improve detection of a dose-response relationship: (1) 0%, (2) 1 to <25%, (3) 25 to <50%, (4) 50 to <75%, (5) 75 to <100%, and (6) 100%. None of the relationships between injury and illness rate and percent ASL trucks exposure levels was statistically significant (i.e., p<0.05), even after adjustment for all three covariates.^ In summary, the present study shows that there is some risk reduction impact of ASL trucks but not statistically significant. The covariates demonstrated a varied yet more modest impact on the injury and illness rate but again, none of the relationships between injury and illness rate and the covariates were statistically significant (i.e., p<0.05). However, as an ecological study, the present study also has the limitations inherent in such designs and warrants replication in an individual level cohort design. Any stronger conclusions are not suggested.^

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"DOE/EV/04734-T1."

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"DOE/EV-0092."