987 resultados para industrial unit


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Ethnography has gained wide acceptance in the industrial design profession and curriculum as a means of understanding the user. However, there is considerable confusion about the particularities of its practice accompanied by the absence of an interoperable vocabulary. The consequent interdisciplinary effort is a power play between disciplines whereby the methodological view of ethnography marginalises its theoretical and analytical components. In doing so, it restricts the potential of ethnography suggesting the need for alternative methods of informing the design process. This article suggests that activity theory, with an emphasis on human activity as the fundamental unit of study, is an appropriate methodology for the generation of user requirements. The process is illustrated through the adaptation of an ethnographic case study, for the design of classroom furniture in India.

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The profession of industrial design is changing and with that so must industrial design education. The newly derived final year industrial design unit at the Queensland University of Technology (QUT) was created to initiate such a change. A designers’ role in industry is no longer limited to the invention process surrounding human cantered design but has now evolved into design led innovation. This paper reflects upon the teaching methods employed over a two-year period and improvements made over that time to the unit. The student project outcome is to produce a design solution that integrates an underlying novel technology into a new product and or service, with business strategies and manufacturing details being fully integrated into the design process. It is this integrated approach to industrial design teaching that will foster a more grounded and resourceful future designer.

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Fault identification in industrial machine is a topic of major importance under engineering point of view. In fact, the possibility to identify not only the type, but also the severity and the position of a fault occurred along a shaft-line allows quick maintenance and shorten the downtime. This is really important in the power generation industry where the units are often of several tenths of meters long and where the rotors are enclosed by heavy and pressure-sealed casings. In this paper, an industrial experimental case is presented related to the identification of the unbalance on a large size steam turbine of about 1.3 GW, belonging to a nuclear power plant. The case history is analyzed by considering the vibrations measured by the condition monitoring system of the unit. A model-based method in the frequency domain, developed by the authors, is introduced in detail and it is then used to identify the position of the fault and its severity along the shaft-line. The complete model of the unit (rotor – modeled by means of finite elements, bearings – modeled by linearized damping and stiffness coefficients and foundation – modeled by means of pedestals) is analyzed and discussed before being used for the fault identification. The assessment of the actual fault was done by inspection during a scheduled maintenance and excellent correspondence was found with the identified one by means of authors’ proposed method. Finally a complete discussion is presented about the effectiveness of the method, even in presence of a not fine tuned machine model and considering only few measuring planes for the machine vibration.

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This study presents 100% degradation of H-acid under optimized conditions using Alcaligenes latus, isolated from textile industrial effluent. Gene/s responsible for H-acid degradation was/were found to be present on plasmid DNA. Addition of bipyridyl to incubated medium resulted in accumulation of terminal aromatic compound, suggesting that catechol may be terminal aromatic compound in degradation pathway of H-acid by A. latus. SDS-PAGE of cell free extracts showed two prominent bands close to molecular weight of catechol 1,2-dioxygenase.

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Phase-locked loops (PLLs) are necessary in applications which require grid synchronization. Presence of unbalance or harmonics in the grid voltage creates errors in the estimated frequency and angle of a PLL. The error in estimated angle has the effect of distorting the unit vectors generated by the PLL. In this paper, analytical expressions are derived which determine the error in the phase angle estimated by a PLL when there is unbalance and harmonics in the grid voltage. By using the derived expressions, the total harmonic distortion (THD) and the fundamental phase error of the unit vectors can be determined for a given PLL topology and a given level of unbalance and distortion in the grid voltage. The accuracy of the results obtained from the analytical expressions is validated with the simulation and experimental results for synchronous reference frame PLL (SRF-PLL). Based on these expressions, a new tuning method for the SRF-PLL is proposed which quantifies the tradeoff between the unit vector THD and the bandwidth of the SRF-PLL. Using this method, the exact value of the bandwidth of the SRF-PLL can be obtained for a given worst case grid voltage unbalance and distortion to have an acceptable level of unit vector THD. The tuning method for SRF-PLL is also validated experimentally.

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Phase-locked loops (PLLs) are necessary in grid connected systems to obtain information about the frequency, amplitude and phase of the grid voltage. In stationary reference frame control, the unit vectors of PLLs are used for reference generation. It is important that the PLL performance is not affected significantly when grid voltage undergoes amplitude and frequency variations. In this paper, a novel design for the popular single-phase PLL topology, namely the second-order generalized integrator (SOGI) based PLL is proposed which achieves minimum settling time during grid voltage amplitude and frequency variations. The proposed design achieves a settling time of less than 27.7 ms. This design also ensures that the unit vectors generated by this PLL have a steady state THD of less than 1% during frequency variations of the grid voltage. The design of the SOGI-PLL based on the theoretical analysis is validated by experimental results.

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[ES]Hasta ahora, el control y monitorización de una instalación industrial se realiza desde la sala de control situada en las propias instalaciones de la planta. Cada unidad de control guarda y envía los datos a un ordenador que después se envían a uno central, siguiendo un orden jerárquico, en el que se visualizan ante un operario. Hoy en día, sin embargo, con el auge de los dispositivos móviles inteligentes, se puede conseguir que esa supervisión de la planta industrial se pueda hacer desde cualquier lugar. Podemos visualizar esos datos de control en nuestra mano y mandar órdenes a cada unidad desde nuestro teléfono inteligente. Esto es lo que se ha conseguido hacer con este proyecto, en el que se ha modelizado una instalación industrial basada en una cadena de montaje con tres unidades.

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Different catches per unit of effort available for industrial and artisanal sardinella fisheries of Senegal have been analysed and compared in order to determine whether they are acceptable indices of abundance. Among the four units of fishing effort studied (total number of sets, number of trips, time spent on fishing ground, searching time), the first and the second seem inadequate in the studied fleets. The two other units, particularly the searching time, allow the calculation of catches per unit of effort which best reflect variations in abundance, although they are not completely free of usual deficiencies.

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Growing environmental concerns caused by natural resource depletion and pollution need to be addressed. One approach to these problems is Sustainable Development, a key concept for our society to meet present as well as future needs worldwide. Manufacturing clearly has a major role to play in the move towards a more sustainable society. However it appears that basic principles of environmental sustainability are not systematically applied, with practice tending to focus on local improvements. The aim of the work presented in this paper is to adopt a more holistic view of the factory unit to enable opportunities for wider improvement. This research analyses environmental principles and industrial practice to develop a conceptual manufacturing ecosystem model as a foundation to improve environmental performance. The model developed focuses on material, energy and waste flows to better understand the interactions between manufacturing operations, supporting facilities and surrounding buildings. The research was conducted in three steps: (1) existing concepts and models for industrial sustainability were reviewed and environmental practices in manufacturing were collected and analysed; (2) gaps in knowledge and practice were identified; (3) the outcome is a manufacturing ecosystem model based on industrial ecology (IE). This conceptual model has novelty in detailing IE application at factory level and integrating all resource flows. The work is a base on which to build quantitative modelling tools to seek integrated solutions for lower resource input, higher resource productivity, fewer wastes and emissions, and lower operating cost within the boundary of a factory unit. © 2012 Elsevier Ltd. All rights reserved.

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Hexachlorobenzene (HCB) is a chlorinated aromatic hydrocarbon that was widely used for seed dressing in prevention of fungal growth on crops, and also as a component of fireworks, ammunition, and synthetic rubbers. Because of its resistance to degradation and mobility, HCB is widely distributed throughout the environment and is accumulated through food chains in different ecosystems. In this study, a preliminary investigation was carried out on the bioaccumulation and the toxic effects of HCB in the microbial (protozoan in particular) communities in the Fuhe River, Wuhan, a water body receiving industrial wastewaters containing HCB and other pollutants, using the standardized polyurethane foam units (PFU) method. Field samples were taken from eight stations established along the Fuhe River in January and August 2006. The concentration ratios of HCB in microbial communities and in water were 9.66-18.64, and the microbial communities accumulated 13.29-56.88 mu g/L of HCB in January and 0.82-10.25 mu g/L HCB in August. Correlation analysis showed a negative correlation between the HCB contents in the microbial assemblage, and the number of species and the diversity index of the protozoan communities. This study demonstrated the applicability of the PFU method in monitoring the effects of HCB on the level of microbial communities.

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The three-dimensional (3D) weaving process offers the ability to tailor the mechanical properties via design of the weave architecture. One repeat of the 3D woven fabric is represented by the unit cell. The model accepts basic weaver and material manufacturer data as inputs in order to calculate the geometric characteristics of the 3D woven unit cell. The specific weave architecture manufactured and subsequently modelled had an angle interlock type binding configuration. The modelled result was shown to have a close approximation compared to the experimentally measured values and highlighted the importance of the representation of the binder tow path.

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Objective: Burnout, a psychological consequence of prolonged work stress, has been shown to coexist with physical and mental disorders. The aim of this study was to investigate whether burnout is related to all-cause mortality among employees. Methods: In 1996, of 15,466 Finnish forest industry employees, 9705 participated in the 'Still Working' study and 8371 were subsequently identified from the National Population Register. Those who had been treated in a hospital for the most common causes of death prior to the assessment of burnout were excluded on the basis of the Hospital Discharge Register, resulting in a final study population of 7396 people. Burnout was measured using the Maslach Burnout Inventory-General Survey. Dates of death from 1996 to 2006 were extracted from the National Mortality Register. Mortality was predicted with Cox hazard regression models, controlling for baseline sociodemographic factors and register-based health status according to entitled medical reimbursement and prescribed medication for mental health problems, cardiac risk factors, and pain problems. Results: During the 10-year 10-month follow-up, a total of 199 employees had died. The risk of mortality per one-unit increase in burnout was 35% higher (95% CI 1.07-1.71) for total score and 26% higher (0.99-1.60) for exhaustion, 29% higher for cynicism (1.03-1.62), and 22% higher for diminished professional efficacy (0.96-1.55) in participants who had been under 45 at baseline. After adjustments, only the associations regarding burnout and exhaustion were statistically significant. Burnout was not related to mortality among the older employees. Conclusion: Burnout, especially work-related exhaustion, may be a risk for overall survival. (C) 2010 Elsevier Inc. All rights reserved.

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O desenvolvimento deste trabalho teve como objectivo a optimização de um sistema de climatização industrial, constituído por quatro centrais de climatização adiabáticas, que apresentam limitações de capacidade de arrefecimento, controlo e eficiência. Inicialmente foi necessária a pesquisa bibliográfica e recolha de informação relativa à indústria têxtil e ao processo de arrefecimento evaporativo. Numa fase posterior foram recolhidos e analisados os diversos dados essenciais à compreensão do binómio edifício/sistema de climatização, para a obtenção de possíveis hipóteses de optimização. Da fase de recolha de informações e dados, destaca-se, também, a realização de análises à qualidade do ar interior (QAI). As optimizações seleccionadas como passíveis de implementação, foram estudadas e analisadas com o auxílio do software de simulação energética dinâmica DesignBuilder e os resultados obtidos foram devidamente trabalhados e ajustados de modo a permitir uma assimilação amigável e de fácil interpretação das suas vantagens e desvantagens, tendo ainda sido objecto de estudo de viabilidade económica. A optimização proposta reflecte uma melhoria substancial das condições interiores ao nível da temperatura e humidade relativa, resultando, ainda assim, numa redução de consumos energéticos na ordem dos 23 % (490.337 kWh), isto é, uma poupança anual de 42.169 € aos custos de exploração e com um período de retorno de 1 ano e 11 meses.

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Se trabajó utilizando una metodología basada en Modelos Lineales Generalizados (MLG). La CPUE fue expresada en toneladas por duración de viaje. Las variables explicativas utilizadas fueron el año, mes, capacidad de bodega, latitud, inercia espacial y distancia a la costa. El modelo tuvo un coeficiente de determinación de 0,485, explicando casi la mitad de la variabilidad de la CPUE observada. La variable con mayor influencia en el modelo fue la capacidad de bodega (49% de la varianza explicada), debido posiblemente a que la flota anchovetera posee una capacidad elevada de captura y que los recursos pelágicos tienden a hiper-agregarse, incluso cuando están siendo fuertemente explotados. La correlación entre la CPUE estandarizada y biomasa estimada por un modelo de captura a la edad (r=0,74) indica que el método basado en MLG es recomendable para la estandarización de la CPUE. Se propone a esta CPUE como una alternativa para monitorear la biomasa de la anchoveta.