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1.
China Occupational Medicine ; (6): 235-241, 2023.
Artigo em Chinês | WPRIM | ID: wpr-996555

RESUMO

Currently, power generation in China is dominated by thermal power, wind power, nuclear power, and hydropower enterprises. The power source mainly comes from thermal power generation. The occupational hazards in thermal power station are noise, high temperature, power frequency electric fields, dust, and chemical toxins and so on, with noise and dust (silica and coal dust) being the primary factors. The occupational hazards in wind power station are noise, power frequency electric fields, high temperature, low temperature, and chemical toxins (sulfur hexafluoride, toluene, styrene, etc.), with noise and power frequency electric fields being the major concerns. The occupational radiation hazards in nuclear power station are gamma rays, beta rays, X-rays, neutrons, alpha rays, and radioactive aerosols. There is special attention in radiation protection but not enough protection in non-radioactive hazards such as noise, high temperature, and ammonia. The occupational hazards in hydropower station are noise, power frequency electric fields, vibration, radon and its de-composites, and chemical toxins, with noise and power frequency electric fields being the primary hazards. Different categories of power generation enterprises should identify key hazards and work site for occupational disease prevention and control based on the features of occupational hazards. Improving occupational health management and protection levels are essential measures.

2.
Braz. arch. biol. technol ; 64(spe): e21210131, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285563

RESUMO

Abstract The growth in the use of solar energy has encouraged the development of techniques for short-term prediction of solar photovoltaic energy generation (PSPEG). Machine learning with Artificial Neural Networks (ANNs) is the most widely used technique to solve this problem. However, comparative studies of these networks with distinct structural configurations, input parameters and prediction horizon, have not been observed in the literature. In this context, the aim of this study is to evaluate the prediction accuracy of the Global Horizontal Irradiance (GHI), which is often used in the PSPEG, generated by ANN models with different construction structures, sets of input meteorological variables and in three short-term prediction horizons, considering a unique database. The analyses were performed with controlled environment and experimental configuration. The results suggest that ANNs using the input GHI variable provide better accuracy (approximately 10%), and their absence increases error variability. No significant difference (p>0.05) was identified in the prediction error models trained with distinct meteorological input data sets. The prediction errors were similar for the same ANN model in the different prediction horizons, and ANNs with 30 and 60 neurons with one hidden layer demonstrated similar or higher accuracy than those with two hidden layers.


Assuntos
Energia Solar , Redes Neurais de Computação , Radiação Solar , Energia Fotovoltaica
3.
Artigo | IMSEAR | ID: sea-209870

RESUMO

The present study put forth with the fundamental objective to the exploration of exoelectrogens from theextremophilic environment and to investigate the electricity generation from them. A total of 20 bacterialcultures were isolated, from which BW2(1) was selected for the further investigation of the microbial fuelcell (MFC). The experimental results performed that the strain Bacillus alkalogaya BW2(1) was capable ofutilizing organic acids and sugars as electron donors to generate electricity. The MFC was constructed and theelectricity generation was measured after various intervals using various parameters and substrates, 937 mVelectricity was generated after 1 hour, but after 48 hours the electricity generation dramatically decreases to570 mV. The effect of pH on MFC was also studied, pH enhanced electricity, indicating the requirement ofpH for bacterium BW2(1). This is a valuable information for bioelectricity production and optimization fromB. alkalogaya BW2(1) has bright future toward the improvement and production of bioelectricity for entirelynew areas of industrial and biotechnological applications.

4.
Braz. arch. biol. technol ; 62(spe): e19190022, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055434

RESUMO

Abstract: Humanity is increasingly dependent on energy, which demand grows every year. Renewable energy sources are consolidated alternatives in the market, previously installed on a small scale but now thought as large plants. The correct operation, taking full advantage of the generation potential, depends on studies of the place of implantation, such as radiation levels, temperature, latitude, etc. Two photovoltaic systems installed in the city of Curitiba were studied in order to monitor their respective performances through figures of merit.


Assuntos
Eletricidade , Energia Fotovoltaica , Centrais Elétricas , Brasil
5.
Electron. j. biotechnol ; 33: 52-62, May. 2018. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1025045

RESUMO

The use of nonrenewable energy sources to provide the worldwide energy needs has caused different problems such as global warming, water pollution, and smog production. In this sense, lignocellulosic biomass has been postulated as a renewable energy source able to produce energy carriers that can cover this energy demand. Biogas and syngas are two energy vectors that have been suggested to generate heat and power through their use in cogeneration systems. Therefore, the aim of this review is to develop a comparison between these energy vectors considering their main features based on literature reports. In addition, a techno-economic and energy assessment of the heat and power generation using these vectors as energy sources is performed. If lignocellulosic biomass is used as raw material, biogas is more commonly used for cogeneration purposes than syngas. However, syngas from biomass gasification has a great potential to be employed as a chemical platform in the production of value-added products. Moreover, the investment costs to generate heat and power from lignocellulosic materials using the anaerobic digestion technology are higher than those using the gasification technology. As a conclusion, it was evidenced that upgraded biogas has a higher potential to produce heat and power than syngas. Nevertheless, the implementation of both energy vectors into the energy market is important to cover the increasing worldwide energy demand.


Assuntos
Biocombustíveis/análise , Lignina/metabolismo , Centrais Elétricas , Digestão Anaeróbia , Biomassa , Energia Renovável , Temperatura Alta , Lignina/química , Metano
6.
Braz. arch. biol. technol ; 61(spe): e18000240, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974155

RESUMO

ABSTRACT Photovoltaic systems have been consolidated in the global energy scenario as an option of low environmental impact energy generation, high reliability and great applicability in urban centers, acting like energy generators near the point of consumption. The Federal University of Technology of Paraná (UTFPR), with the proposal of testing the performance of grid-connected photovoltaic systems (On Grid PV Systems) and help its entry into the Brazilian energy matrix, implemented this technology in two of its buildings: Green Office (GO) And Neoville. This paper analyzed the effects of dust on the Photovoltaic Systems performance based on daily energy. The analysis was carried out from the solar irradiance data from the places where the panels are installed and the electrical power data collected at the mass memory of the inverter of the two systems, in order to be analyzed and compared before and after the cleaning of the photovoltaic modules. The results at the end of the study indicate that dust directly impacts in the performance of the PV system.


Assuntos
Poeira , Meio Ambiente , Consumo de Energia , Energia Fotovoltaica
7.
Braz. arch. biol. technol ; 61(spe): e18000280, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974136

RESUMO

ABSTRACT Photovoltaic solar energy is increasingly present in the urban environment through the distributed generation. This kind of generation is characterized by the installation along the distribution network feeders, in low or medium voltage, and contribute to provide energy near the point of consumption. In this sense, this study aims to analyze the demand and consumption curves of the buildings of the Federal University of Technology - Paraná (UTFPR) in the Neoville's headquarters. The methodology consists in the application of COPEL's CAS Hemera platform, in order to determine the potential for the implementation of the Grid-Connected Photovoltaic Systems in this place, because they allow the reduction of costs with electric energy from the application of distributed generation. In February 2016, a grid-connected photovoltaic system was installed in one of the university's blocks, which generated approximately 11 MWh of electric energy this year. This work proposes a scenario for the expansion of this photovotaic system and presents the contribution of photovoltaic generation, using the available coverage showing the shifting or reduction of energy demand peaks and the energy contribution to UTFPR's Neoville headquarters. The results of this study show that the proposed scenario will effectively change the profile of the university demand curve.


Assuntos
Energia Fotovoltaica , Brasil , Eletricidade , Fontes Geradoras de Energia
8.
Braz. arch. biol. technol ; 61(spe): e18000360, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974126

RESUMO

ABSTRACT This study presents a system of conversion of mechanical energy produced by physical activity into electric energy obtained by a CC generator coupled to the pedal of an ergometric bicycle. It presents the converter that will be used to adjust the voltage and power coming from the system, as well as the details of the converter design, the simulation and the primary experimental results of the structure. The methodological procedures related to the development of the converter and data acquisition through simulation were carried out based on the bibliographic research. The study is documentary as equipment manuals were used.


Assuntos
Fontes Geradoras de Energia , Esforço Físico , Veículos Off-Road
9.
Braz. arch. biol. technol ; 61(spe): e18000510, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974121

RESUMO

ABSTRACT The present study evaluates the economic viability of the application of solar energy for electric power generation via the use of photovoltaic systems in a residential consumption unit in the city of Curitiba. Since the energy from the sun is abundant, clean, renewable and has the potential to compete in productivity and profitability, the evaluation of the applicability of these systems in homes, not only in industrial parks, is of great interest. A household with the determined consumption profile was chosen for this case study through simulations with the HomerPro software. After analyzing the data, the photovoltaic potential of the State of Paraná was estimated to investigate the possibility of photovoltaic generation growth in the state energy matrix and its consequences.


Assuntos
Energia Solar/economia , Energia Renovável/economia , Brasil , Energia Fotovoltaica/economia
10.
Malaysian Journal of Microbiology ; : 108-112, 2018.
Artigo em Inglês | WPRIM | ID: wpr-732358

RESUMO

@#Aims: To study the performance of SMFC in the terms of power generation and toxic metals removal. This study was also focused on the characterization of SMFC electro-microbiology. Methodology and results: A SMFC was designed and loaded with sediment and overlying water. This SMFC was synchronized with wireless data logger acquisition system. The toxic metals removal capacity was measured by atomic absorption spectroscopy. The characterization of SMFC bacteria was done by 16S rRNA.In this study the experiments were carried out in a dual-chamber SMFC with external resistances 30 kΩ-50 Ω. The SMFC was produced power about 630 mV with maximum power density 40 mW/m2and current density 250 mA/m2. After 120 days of operation, SMFC removed cadmium and copper about 22.6 and 150 mg/kg, respectively. The SMFC also showed high cadmium (86%) and copper (90%) removal at pH 7.0 and temperature 40 °C. The most dominant bacterial community at anode and cathode was identified as Pseudomonas spp. which could be function as exoelectrogen. Conclusion, significance and impact of the study: The results indicated that the SMFC system could be applied as a long term and effective tool for the removal of cadmium and copper contaminated sediments and supply power for commercial devices. The Pseudomonas spp. may be used as a genetic donor for the other non-exoelectrogens strains.

11.
The Journal of the Korean Orthopaedic Association ; : 655-665, 1998.
Artigo em Coreano | WPRIM | ID: wpr-644653

RESUMO

It is known that the toe-flexors exert some power generation in ankle plantar flexion. However, there has been no paper published in which the power generation was quantified. The purpose of this paper, therefore, is to quantify the amount of contribution of the toe-flexors to the ankle plantar-flexion in normal and rapid walking using the kinetic data of three dimensional gait analysis system. In order to restrict the action of the toe-flexors, we designed special braces which can be applied to the forefeet of the examinee during walking. We performed the gait analysis in ten normal adult volunteers with and without braces, and evaluated the moment and power of toe-flexors during terminal stance and pre-swing phase of gait cycle. Gait analysis was done with the VICON 3-dimensional motion analysis system (VICON, Oxford Metrics, Oxford, England) and 2 force plates (AMTI, Advanced Mechanical Technoiogy, Newton, MA, U.S.A,). The kinetic results are as follows: l. Average speeds of normal and rapid walking were 1.12m/sec and 1.41m/sec respectiveIy. 2. In normal walking, peak ankle plantar-tlexion moment decreased 5.5% with braces, and sum of ankle plantar-flexion moment decreased 12.3% with braces. Both of the results were not significant statistically (p>0.05). Peak ankle power generation decreased 11.0% with braces, and sum of ankle power generation decreased 10.4% with braces. These decreases were also insignificant statistically (p>0.05). 3. In rapid walking, peak ankle plantarflexion moment decreased 26.7% with braces. The decrease was horderline significant statistically (p=0.062). The sum of ankle plantar-tlexion moment decreased 26.6% with braces, but the decrease was not significant statistically (p>0.05). Peak ankle power generation decreased 40.2% with braces, and sum of ankle power generation decreased 37.9% with braces. These decreases showed borderline significance statistically (p=0.062). In conclusion, toe-flexors may contribute about 10% of the total ankle plantar-flexion power generation, and the contribution will be increased with increase of walking velocity. We must be very careful to sacrifice the toe-flexors in cases with weak triceps power.


Assuntos
Adulto , Humanos , Tornozelo , Braquetes , Marcha , Dedos do Pé , Voluntários , Caminhada
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