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2.
PLoS One ; 16(6): e0252756, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34101767

RESUMO

Rapid technological development has revolutionized the industrial sector. Internet of Things (IoT) started to appear in many fields, such as health care and smart cities. A few years later, IoT was supported by industry, leading to what is called Industry 4.0. In this paper, a cloud-assisted fog-networking architecture is implemented in an IoT environment with a three-layer network. An efficient energy and completion time for dependent task computation offloading (ET-DTCO) algorithm is proposed, and it considers two quality-of-service (QoS) parameters: efficient energy and completion time offloading for dependent tasks in Industry 4.0. The proposed solution employs the Firefly algorithm to optimize the process of the selection-offloading computing mode and determine the optimal solution for performing tasks locally or offloaded to a fog or cloud considering the task dependency. Moreover, the proposed algorithm is compared with existing techniques. Simulation results proved that the proposed ET-DTCO algorithm outperforms other offloading algorithms in minimizing energy consumption and completion time while enhancing the overall efficiency of the system.


Assuntos
Indústrias/métodos , Internet das Coisas , Software , Computação em Nuvem , Indústrias/instrumentação
3.
PLoS One ; 15(12): e0243107, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33264358

RESUMO

The hybrid electromagnetic and elastic foil gas bearing is explored based on the radial basis function (RBF) neural network in this study so as to improve its stabilization in work. The related principles and structure of hybrid electromagnetic and elastic foil gas bearings is introduced firstly. Then, the proportional, integral, and derivative (PID) bearing controller is introduced and improved into two controllers: IPD and CPID. The controllers and hybrid bearing system are controlled based on the RBF neural network based on deep learning. The characteristics of the hybrid bearing system are explored at the end of this study, and the control simulation research is developed based on the Simulink simulation platform. The effects of the PID, IPD, and CIPD controllers based on the RBF neural network are compared, and they are also compared based on the traditional particle swarm optimization (PSO). The results show that the thickness, spread angle, and rotation speed of the elastic foil have great impacts on the bearing system. The proposed CIPD bearing control method based on RBF neural network has the shortest response time and the best control effect. The controller parameter tuning optimization starts to converge after one generation, which is the fastest iteration. It proves that RBF neural network control based on deep learning has high feasibility in hybrid bearing system. Therefore, the results provide an important reference for the application of deep learning in rotating machinery.


Assuntos
Indústrias/instrumentação , Simulação por Computador , Aprendizado Profundo , Fenômenos Eletromagnéticos , Desenvolvimento Industrial
5.
Work ; 52(1): 185-94, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26410233

RESUMO

BACKGROUND: Work of crane operators is very difficult and demanding. Therefore, it is very important that the cabin of a crane be designed on the basis of relevant anthropometric data. However, it is very difficult to find a research that considers anthropometric convenience of crane cabins. OBJECTIVE: From the theoretical viewpoint, it is important to perceive and to classify effects of the anthropometric incompatibility of crane cabins. Globally, the objective is to consider the anthropometric convenience of existing crane cabins, and possibilities for improvements of their design from the ergonomic point of view. In this regard, it is significant to detect constraints that impede or hinder the work of the crane operators, which could be overcome with certain anthropometric solutions. The main objective is to examine whether and to what extent is justifiable to use anthropometric data that are obtained on the basis of general (national) population, during designing the crane cabins. METHODS: For the assessment of existing crane cabins and the work of operators, four methods were used: observation of the work of the operators and design solutions of the cabins, the checklist approach, interviewing of operators and the experimental research based on obtaining the data on the population of crane operators. RESULTS: Results of the analysis based on the method of observation, analysis based on the application of the checklist, as well as interviewing of the operators indicate that certain construction constraints of the components in the cabins are the main reasons of reduced visibility and improper working postures of operators. All this has caused the emergence of continuous musculoskeletal loading of the crane operators. The results of the anthropometric research that were obtained on the population of crane operators in this case study suggest that there is a statistically significant difference, when compared data of this population of workers with anthropometric data from the general population. CONCLUSIONS: Analyzed workplaces in crane cabins do not correspond to the majority of operators from the anthropometric standpoint. The conducted anthropometric analysis has been indicated that could be made the mistake, if dimensions of the cabin and layout of equipment would be relied on data derived from the general population of citizens. In order to achieve greater precision in the design and configuration of equipment, it is recommended using the data that are obtained directly on the population of the crane operators when designing the cabin.


Assuntos
Antropometria , Ergonomia , Indústrias/instrumentação , Sistemas Homem-Máquina , Desenho de Equipamento , Humanos , Indústrias/economia , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Análise e Desempenho de Tarefas
6.
Phys Med ; 31(6): 601-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25937007

RESUMO

In spite of its long demonstrated potential, microbeam radiosurgery (MBRS) has yet to be developed into a clinical tool. This article examines the problems associated with MBRS, and potential solutions. It is shown that a path to a clinically useful device is emerging.


Assuntos
Fracionamento da Dose de Radiação , Indústrias/instrumentação , Radiocirurgia/instrumentação , Radioterapia de Alta Energia/instrumentação , Radioterapia de Alta Energia/métodos , Síncrotrons/instrumentação , Animais , Desenho de Equipamento , Medicina Baseada em Evidências , Cirurgia Geral , Humanos , Avaliação da Tecnologia Biomédica , Resultado do Tratamento
7.
Sci Total Environ ; 468-469: 176-85, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24029690

RESUMO

Decommissioning of manufacturing plant in the chemical industry includes inspection of the surfaces of production equipment for potential contamination and associated health risks. In the present study wipe-samples were taken from the surfaces of dicofol manufacturing equipment at a chemical factory in north China and analyzed for chemicals of concern (COCs). Occupational hygiene assessment was conducted to assess the risks to demolition workers and health risk assessment was performed to evaluate the risks to demolition and general industrial workers. The concentrations of COCs on the equipment surfaces were found to be 0.54-3.75 × 10(4)mg DDTs m(-2) and 0.15-4.38 × 10(3)mg dicofolm(-2). The average concentration of p,p'-DDT does not represent an unacceptable risk to the demolition workers using occupational hygiene assessment. Under the industrial scenario the carcinogenic risks of COCs ranged from 2.28 × 10(-7) to 1.79 × 10(-2) for p,p'-DDT, 6.18 × 10(-7) to 3.04 × 10(-3) for p,p'-DDD and 1.89 × 10(-6) to 0.16 for p,p'-DDE. The non-carcinogenic hazard indices ranged from 3.86 × 10(-3) to 3.03 × 10(2) for p,p'-DDT and 1.16 × 10(-3) to 33.94 for dicofol. Both carcinogenic risk and hazard index of COCs under the industrial scenario were higher than under the demolition scenario. Oral ingestion and dermal contact were the major pathways and accounted for >88% of the total exposure of COCs. Parameter sensitivity analysis shows that equipment surface concentration (Cs), frequency of contact with surface (EV), fraction of dust transferred from surface to skin (FTss) and exposure frequency (EF) were the most sensitive parameters and these should be acquired on a site-specific basis. The accuracy of the risk assessment was controlled largely by the variation in the sensitive parameters and the uncertainty of the exposure model for the inhalation pathway.


Assuntos
Carcinógenos/análise , DDT/análise , Dicofol/análise , Indústrias/instrumentação , Exposição Ocupacional/análise , Medição de Risco/estatística & dados numéricos , China , Cromatografia Gasosa-Espectrometria de Massas , Medição de Risco/métodos , Estatísticas não Paramétricas
8.
Int J Occup Saf Ergon ; 17(3): 277-86, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21939600

RESUMO

A global index of machines was developed to assess noise emitted by machines and to predict noise levels at workstations. The global index is a function of several partial indices: sound power index, index of distance between the workstation and the machine, radiation directivity index, impulse and impact noise index and noise spectrum index. Tests were carried out to determine values of the global index for engine-generator; the inversion method for determining sound power level was used. It required modelling each tested generator with one omnidirectional substitute source. The partial indices and the global index were simulated, too. The results of the tests confirmed the correctness of the simulations.


Assuntos
Acústica , Indústrias/instrumentação , Ruído Ocupacional , Humanos , Espectrografia do Som
9.
ISA Trans ; 50(1): 44-52, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21036353

RESUMO

The receding horizon H(∞) control (RHHC) problem is investigated in this paper for a class of networked control systems (NCSs) with random delay and packet disordering. A new model is proposed to describe the NCS with random delay which may be larger than one sampling period. The random delay is modeled as a Markov chain while the closed-loop system is described as a Markovian jump system. Sufficient conditions for the closed-loop NCS to be stochastically stable and the performance index to be upper bounded are derived by using the receding optimization principle. Furthermore, by solving a semi-definite programming (SDP) with linear matrix inequalities (LMIs) constraint, a piecewise-constant receding horizon H(∞) controller is obtained, and the designed piecewise-constant controller ensures that the closed-loop NCS achieves a prescribed H(∞) disturbance attenuation level. Finally, an illustrative example is given to demonstrate the effectiveness of the proposed method.


Assuntos
Indústrias/instrumentação , Redes Neurais de Computação , Algoritmos , Cadeias de Markov , Modelos Estatísticos , Dinâmica não Linear , Distribuição Aleatória , Processos Estocásticos
11.
Bioresour Technol ; 102(3): 2712-23, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21109426

RESUMO

A detailed model based on a non-dimensional transportation factor is developed to assess the economics of biomass collection, transportation, and storage. The optimum plant size for bio-refineries is investigated; ethanol production from corn stover via dilute acid hydrolysis is presented as a case study. The conversion of straight-line, farm-to-plant distances to road distances via a winding factor leads to a shift in the distribution of transportation distances towards shorter hauls. The capital investment scaling exponent was calculated using the model developed at the National Renewable Energy Laboratory (Aden et al., NREL/TP-510-32438, 2002) and found to be 0.7. The cost of the delivered corn stover is proportional to the square root of the inverse of the farmer participation; as a consequence, bio-fuel producers intending to use agricultural residues as feedstock should work towards a farmer participation of fifty percent. Costs associated with storage represent a significant portion of the production cost.


Assuntos
Biocombustíveis/economia , Reatores Biológicos/economia , Etanol/economia , Indústrias/economia , Indústrias/instrumentação , Modelos Econômicos , Meios de Transporte/economia , Biomassa , Simulação por Computador , Estados Unidos
12.
Science ; 329(5993): 793-6, 2010 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-20705852

RESUMO

Rapid growth in demand for lignocellulosic bioenergy will require major changes in supply chain infrastructure. Even with densification and preprocessing, transport volumes by mid-century are likely to exceed the combined capacity of current agricultural and energy supply chains, including grain, petroleum, and coal. Efficient supply chains can be achieved through decentralized conversion processes that facilitate local sourcing, satellite preprocessing and densification for long-distance transport, and business models that reward biomass growers both nearby and afar. Integrated systems that are cost-effective and energy-efficient will require new ways of thinking about agriculture, energy infrastructure, and rural economic development. Implementing these integrated systems will require innovation and investment in novel technologies, efficient value chains, and socioeconomic and policy frameworks; all are needed to support an expanded biofuels infrastructure that can meet the challenges of scale.


Assuntos
Biocombustíveis , Lignina , Agricultura/economia , Agricultura/métodos , Biocombustíveis/economia , Biomassa , Comércio , Custos e Análise de Custo , Desenvolvimento Econômico , Indústrias/economia , Indústrias/instrumentação , Indústrias/métodos , Tecnologia , Meios de Transporte/economia , Meios de Transporte/métodos
13.
ISA Trans ; 49(4): 443-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20488438

RESUMO

This paper presents the development of a microdispensing system based on a contacting method, with an aim to lowering production and maintenance cost. The liquid, to be dispensed, is brought into contact with the work piece, thus dispensing a droplet by making use of the adhesion force between the liquid and the work piece. A piezoelectric actuator is employed as the drive for the system to achieve high precision. The control of the system is accomplished with a PID controller; controlling the dispensing process and trajectory tracking.


Assuntos
Indústrias/instrumentação , Simulação por Computador , Eletrônica , Gravitação , Indústrias/economia , Pressão , Reprodutibilidade dos Testes , Tensão Superficial , Viscosidade
14.
ISA Trans ; 49(2): 244-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20006328

RESUMO

In this paper we show how a simple methodology for the set-point following performance assessment and automatic tuning of a PI controller can be employed effectively in a real industrial application. In particular, a flow control loop in a pharmaceutical plant is considered. Practical issues related to the implementation in a Distributed Control System are discussed. Results show that the technique is capable of significantly improving the performance of the controller.


Assuntos
Indústria Farmacêutica/instrumentação , Indústrias/instrumentação , Algoritmos , Eletrônica , Modelos Lineares , Reprodutibilidade dos Testes
15.
Pak J Biol Sci ; 12(18): 1246-52, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20384277

RESUMO

Vero cells are utilized for production of rabies vaccine. This study deals with the optimize quantity media require for the rabies vaccine production in the smooth roller surface. The rabies virus (Pasteur vaccine strain) is infected to monolayer of the various experimented bottles. To analyze the optimal quantity of media for the production of rabies viral harvest during the process of Vero cell derived rabies vaccine. The trials are started from 200 to 400 mL (PTARV-1, PTARV-2, PTARV-3, PTARV-4 and PTARV-5). The samples are taken in an appropriate time intervals for analysis of In Process Quality Control (IPQC) tests. The collected viral harvests are further processed to rabies vaccine in a pilot level and in addition to scale up an industrial level. Based on the evaluation the PTARV-2 (250 mL) show highly encouraging results for the Vero cell derived rabies vaccine production.


Assuntos
Técnicas de Cultura de Células , Meios de Cultura/química , Indústrias , Vacina Antirrábica/biossíntese , Animais , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Chlorocebus aethiops , Humanos , Indústrias/instrumentação , Indústrias/métodos , Polietilenotereftalatos/química , Polietilenotereftalatos/metabolismo , Raiva/prevenção & controle , Vírus da Raiva/imunologia , Padrões de Referência , Células Vero
16.
Australas Phys Eng Sci Med ; 31(1): 42-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18488963

RESUMO

The Mahlo Gravimat densitometers/gauges located at the Feltex carpet factory in Christchurch, New Zealand, contain the radionuclide strontium-90 (Sr-90). Accurate dose/dose rate estimation is always an important concern from a radiation protection point of view. The EGSnrc/BEAMnrc Monte Carlo code was used to create a model of one gauge to determination of the radiation dose distributions and dose rates in air from the Sr-90 source within the gauge. The model was then modified to include a Perspex shield on the surface of the gauge as a possible method of lowering the radiation levels. With this addition, the model predicted an overall reduction in dose rates of 30%. Although no experimental benchmarking was able to be performed due to simplifications in the model and the lack of reliable experimental data, we believe that Monte Carlo methods could be a valuable addition in the design process of any devices, industrial or otherwise, that contain or use radioactive materials. Furthermore, such methods may aide or guide any investigations undertaken as part of radiation protection surveys.


Assuntos
Indústrias/instrumentação , Modelos Estatísticos , Exposição Ocupacional/análise , Proteção Radiológica/métodos , Radiometria/métodos , Estrôncio/análise , Transdutores , Simulação por Computador , Método de Monte Carlo , Doses de Radiação
18.
Int J Med Robot ; 3: 72-81, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17441029

RESUMO

BACKGROUND: Protons beams deliver targeted radiation doses with greater precision than is possible with electrons or megavoltage X-ray photons, but to retain this advantage, patient positioning systems at proton clinics must meet tighter accuracy requirements. For this and other reasons, robots were incorporated into the treatment room systems at MPRI. METHODS: The Midwest Proton Radiotherapy Institute (MPRI) is the first radiotherapy facility in the United States to use commercial robots with six degrees of freedom for patient positioning, rather than a traditional bed with four degrees of freedom. RESULTS: This paper outlines the ways in which robots are used at MPRI and attempts to distil insights from the experience of treating over 200 radiotherapy patients with a robotic system from February 2004 to late 2006. CONCLUSIONS: The system has performed well, and with great reliability, but there is room for future improvement, especially in ease of use and in reducing the time to get patients into position.


Assuntos
Postura , Terapia com Prótons , Radioterapia Assistida por Computador/instrumentação , Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/instrumentação , Restrição Física/instrumentação , Robótica/instrumentação , Desenho de Equipamento , Humanos , Indústrias/instrumentação , Radioterapia Conformacional/métodos , Restrição Física/métodos , Robótica/métodos , Avaliação da Tecnologia Biomédica
19.
Surg Technol Int ; 15: 41-3, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17029160

RESUMO

The exclusive charge-coupled device (CCD) camera system for the endoscope and electronic fiberscopes are in widespread use. However, both are usually stationary in an office or examination room, and a wheeled cart is needed for mobility. The total costs of the CCD camera system and electronic fiberscopy system are at least US Dollars 10,000 and US Dollars 30,000, respectively. Recently, the performance of audio and visual instruments has improved dramatically, with a concomitant reduction in their cost. Commercially available CCD video cameras with small monitors have become common. They provide excellent image quality and are much smaller and less expensive than previous models. The authors have developed adaptors for the popular mini-digital video (mini-DV) camera. The camera also provides video and acoustic output signals; therefore, the endoscopic images can be viewed on a large monitor simultaneously. The new system (a mini-DV video camera and an adaptor) costs only US Dollars 1,000. Therefore, the system is both cost-effective and useful for the outpatient clinic or casualty setting, or on house calls for the purpose of patient education. In the future, the authors plan to introduce the clinical application of a high-vision camera and an infrared camera as medical instruments for clinical and research situations.


Assuntos
Endoscópios , Aumento da Imagem/instrumentação , Indústrias/instrumentação , Microcirurgia/instrumentação , Gravação em Vídeo/instrumentação , Cirurgia Vídeoassistida/instrumentação , Sistemas Computacionais , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Aumento da Imagem/métodos , Indústrias/economia , Microcirurgia/economia , Miniaturização , Interface Usuário-Computador , Gravação em Vídeo/economia , Gravação em Vídeo/métodos , Cirurgia Vídeoassistida/economia , Cirurgia Vídeoassistida/métodos
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