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171.
S. Mekhilef R. Saidur S. M. Said P. H. Hong M. R. Islam 《Clean Technologies and Environmental Policy》2014,16(1):23-35
In this paper, a survey was conducted on a residential condominium to estimate energy use by different household appliances along the lighting energy estimation in public areas. It has been found that about 2.17 GWh of energy is used in the condominium annually by different types of household appliances and lightings in public areas. As there is significant potential to reduce the energy used, different energy savings measures have been applied and energy savings, bill savings, life cycle cost analysis have been estimated and presented in this paper. It has been found that a cumulative amount of 2.4 GWh of energy can be saved for about 10 years with the implementation of different energy savings strategies proposed for appliances and lighting in public areas. However, good maintenance practices and good energy management practices should be employed continuously to maintain high energy efficiency and high performance of the equipment used and the entire building. It has been found that some of the measures like reducing air conditioning load and reducing heat gain through window tinting are economically very viable as payback period is very short. More advantageously, some of the measures can be implemented without investing significant cost. Ultimately, a key driver in the success of energy efficiency is the education and attitude of the stakeholders in the building industry, and end users who are committed to practice energy saving measures. 相似文献
172.
Many methods for multinational License Plate Detection (LPD) have been proposed in recent times but most of them are not sophisticated enough to handle complex backgrounds. Moreover, their ability to handle various environmental and illumination conditions has been limited and still needs improvement. In this paper, we propose a novel technique to detect license plates of vehicles regardless of their color, size, and content. As the rear vehicle lights are an essential part of any vehicle, we reduce the image processing area to eliminate the complex background by detecting the rear-lights as the license plates are in a certain range of these lights. Heuristic Energy Map (HEM) of the vertical edge information in the Region of Interest (ROI) is calculated and area with the dense edges is selected using a unique histogram approach which is considered to be the license plate. The proposed algorithm is tested on 855 images from various countries including China, Pakistan, Serbia, Italy and various states of America. Experimental results show that the proposed method is able to detect license plates 90.4% of times despite of complex backgrounds in 0.25 s on average that can achieve real time performance. 相似文献
173.
《Ceramics International》2017,43(8):6221-6231
In the present work, an investigation of the mechanosynthesis of calcium hydroxyapatite (HA, Ca10(PO4)6(OH)2) from a mixture of calcium oxide (СаО) and ammonium hydrophosphate ((NH4)2HPO4) and mechanotreatment of HA in a planetary mill with the use of steel drums and milling body has been performed. The obtained results have shown that the mechanosynthesis of crystalline nanodisperse HA proceeds through the stage of formation of an amorphous material. The temperature treatment of HA powders at 1000 °C has enabled us to establish the influence of the treatment time on the phase composition of the powders and establish the following sequence of phase transformations: Ca10(PO4)6(OH)2→β-Ca3(PO4)2 (tmilling~2 h), β-Ca3(PO4)2→α-Ca3(PO4)2 (tmilling~5 h), β-,α-Ca3(PO4)2→Ca10(PO4)6(OH)2 (tmilling~7 h).The mechanosynthesis and mechanotreatment of hydroxyapatite in steel drums with steel balls is accompanied by the contamination of hydroxyapatite by their wear debris (iron + manganese). A large part of oxidized iron forms superparamagnetic inclusions distributed in HA powder. A small part of Fe3+ and Mn2+ ions from the steel wear debris enters into the hydroxyapatite lattice, substituting Ca2+ ions. As a result, a nanocomposite powder consisting of hydroxyapatite, alloyed by Fe3+ and Mn2+ ions and ferrite inclusions forms. The phase composition of HA powders, the degree of their alloying by Fe3+ and Mn2+ ions, and the content of ferrite inclusions can be controlled by changing the time of mechanotreatment. 相似文献
174.
《Food Control》2014
The main purpose of this work was to evaluate the significance of food safety in domestic environments. In this study, several points in 15 houses (handles of doors, refrigerators and dishwashers, cooking stove knobs, surfaces of preparation of foods, taps and kitchen towels, as well as from domestic animals' feet that usually have access to the kitchen area, and WC knobs and taps) were sampled and tested for detection and quantification of Enterobacteriaceae, Staphylococcus coagulase-positive, Escherichia coli, Listeria spp. and Campylobacter spp. A questionnaire was also prepared and administered to the person responsible for domestic tasks in order to evaluate their experience of hygienic practices. The results showed a total of 125 Enterobacteriaceae spp. isolates, 86 Staphylococcus coagulase-positive isolates, 5 Listeria spp., 13 E. coli isolates and no Campylobacter spp. was found. Most of the isolates were found distributed by the entire house, with handles, knobs and domestic animals' feet being the points more contaminated. Also, there was no relation between the answers to the questionnaires administered and the microbiological results obtained. These results revealed the need to develop some education campaigns designed to educate consumers in good hygiene practices at home. 相似文献
175.
In this study, the central composite design of the response surface methodology was employed to investigate the effects of reaction temperature, catalyst concentration and cross flow circulation velocity on the production of biodiesel in a TiO2/Al2O3 membrane reactor. High‐quality palm oil biodiesel was produced by combination of alkali transesterification and separation processes in the ceramic membrane reactor. The optimum conditions for the conversion of palm oil to biodiesel in the ceramic membrane reactor were as follows: 70°C reaction temperature, 1.12 wt% catalyst concentration and 0.211 cm s? 1 cross flow circulation velocity. The physical and chemical properties of the produced biodiesel were determined and compared with the standard specifications. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
176.
Predicting ground temperature is an important part of the analysis of geothermal resources assessment and use. Thus, we develop and validate one-dimensional numerical model for heat and mass transfer in partially frozen soils. The model is implemented in HVACSIM Plus and used to simulate the thermal regime of soil profile. In addition to modeling heat conduction, model variations also includes moisture transfer, snow accumulation and melting, and soil freezing and thawing. The results are compared against experimental measurements of ground temperature for three locations in Montana, USA. The differences between simulated depth temperature with and without snow cover and freezing and thawing of soil reveal that ground temperatures are predominantly influenced by these two factors. Considering moisture transfer slightly improves temperature predictions, although it increases computational time by one order of magnitude. To balance computational efficiency with prediction accuracy, we propose an equivalent moisture content of 40–60% saturation in predicting ground temperature. 相似文献
177.
Electrical and optical analyses of trapping phenomenon with temperature dependence of organic device
Carrier mechanism in actual organic devices is not simple, owing to the dielectric nature of active organic semiconductor layers, the complexity of the organic device interface, carrier trapping effects by stress biasing, and others. By coupling the conventional electrical measurement, e.g., current–voltage, capacitance–voltage and capacitance-frequency measurements, with optical charge modulation spectroscopy (CMS) measurement, we studied the hysteresis behavior and the temperature dependence of indium tin oxide/polyimide/6,13-Bis(triisopropylsilylethynyl)pentacene(TIPS-pentacene)/Au diodes to understand the effect of carrier trapping caused by injected carriers. The coupled electrical and optical measurements were very helpful to clarify carrier injection that was followed by carrier trapping in the diode, in terms of hysteresis behavior. CMS measurement was used to observe energetic states of carriers in TIPS-pentacene double-layer diode. Finally, the carrier mechanism in organic diodes was discussed by analyzing the diodes as a Maxwell-Wagner effect element. 相似文献
178.
The objective of the study is to investigate the short-run and long-run causality relationship among energy (electricity production from renewable sources), carbon dioxide emissions, natural resource depletion, Gross Domestic Product (GDP) and poverty in selected SAARC countries, namely, Bangladesh, India, Nepal, Pakistan and Sri Lanka, over a period of 1975–2010. The results show that there is bidirectional Granger causality between carbon dioxide emissions & natural resource depletion in Nepal and between energy production & poverty in Pakistan. For the other three countries, the Granger causality runs from energy production to poverty in Bangladesh and India, and from poverty to energy production in Sri Lanka. The results of panel group Fully Modified OLS (FMOLS) indicates that GDP and poverty has a positive impact while carbon dioxide emission has a negative impact on energy production. Similarly, an increase in energy production leads to decrease in carbon emissions, where as, natural resource depletion increase carbon emissions in selected SAARC countries. Subsequently, an increase in energy production leads to increase in GDP which further increase carbon dioxide emission in SAARC region. 相似文献
179.
《Ceramics International》2017,43(18):16331-16339
In this study, nanosized nickel oxide (NiO) and nickel (Ni) powders were synthesised via glycine-nitrate (GN) combustion process, assisted by nanocrystalline cellulose (NCC) as a template. Despite the unique morphology of NCC, it has yet to be applied as a sacrificial bio-template for GN combustion process. In addition, NiO and Ni nanoparticles were obtained at relatively low temperatures in this study, whereby the calcination temperatures were varied from 400 °C to 600 °C, with calcination durations of 2, 4, and 6 h. The morphological analysis of the resulting products were conducted using FESEM, which showed uniformly dispersed NiO and Ni particles with average crystallite size of 25 nm and 27 nm, respectively. These results were confirmed using X-ray diffraction (XRD) technique. The Raman and Fourier transform infrared (FTIR) spectra revealed that the molecular fingerprints of the samples were in agreement with each other. Further analyses revealed that samples calcined at 600 °C for 4 h showed the lowest particle size for pure NiO, whereas the lowest particle size for pure Ni was obtained at 400 °C for 4 h. The TGA results were also consistent with the XRD analysis, whereby pure Ni was initially formed and upon heating, had gradually converted into NiO. 相似文献
180.
《Ceramics International》2016,42(7):8351-8359
Dense and crack free six-layered functional graded materials were successfully produced by Spark Plasma Sintering by combining 3 mol% Y2O3-partially stabilized ZrO2 (3Y-PSZ) and 316L stainless steel. All the sintered products consisted of a steel free layer on one side and a cermet composite containing 50 vol% of both constituents on the opposite side. Conversely, the stainless steel concentration in the interlayers was progressively changed following diverse spatial profiles.It was found that the temperature interval from 1080 to 1180 °C required for the full consolidation from the 50 vol% composite layer to the 3Y-PSZ one, respectively, can be reached when adopting a specific die configuration where the cross section was varied from 30 to 28 mm, respectively. Correspondingly, the densification level of each layer, as well as the related hardness and fracture toughness properties, were highly enhanced with respect to the standard cylindrical die. In addition, a significant improvement of the material toughness was obtained when the material concentration exponent was decreased from 2 to 1, whereas this effect tends to vanish when such parameter was further reduced to 0.5. 相似文献