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11.
Trade‐off analysis, one of the key elements of transportation asset management (TAM), helps decision makers to not only quantify how different resource allocations affect system performance but also investigate the trade‐off relationships between cost and performance measures and between different performance measures. In the fast‐growing field of TAM, researchers are beginning to quantify the trade‐offs among the performance measures. A successful quantification of these trade‐offs is important for the practice because the highway agency decision makers responsible for project selection have long been stymied by a lack of knowledge of the extent to which different decisions lead to different performance trade‐offs. In a follow‐up to recent research efforts that have sought to address this issue, this article presents a further improved methodology to facilitate the analysis of trade‐offs in TAM. First, a general multiobjective optimization framework for TAM is established. Next, the developed hybrid method is presented, which is then shown to quicken the generation of Pareto frontiers for the purpose of conducting trade‐off analysis. Using a case study, the proposed hybrid method, which was implemented on a computer to generate Pareto frontiers, ultimately converged faster and generated better‐distributed Pareto frontiers compared to the NSGA II method of Pareto frontier generation in the TAM context. Using the generated Pareto frontiers, trade‐off analysis between cost and performance measures and between performance measures are demonstrated in this article.  相似文献   
12.
Neural Computing and Applications - In this paper, a bio-inspired computational intelligence technique is presented for solving nonlinear doubly singular system using artificial neural networks...  相似文献   
13.
Mitigation in endosulfan residues was determined in spinach, cauliflower, potato, brinjal, tomato, and okra by using different techniques. The endosulfan residues were determined in 66 samples of different vegetables, and it was found that the highest endosulfan residues (mg kg?1) were at the raw stage in okra (1.71), brinjal (1.50), and spinach (1.16), respectively. The residue of endosulfan was lowest in potato (0.130) mg kg?1. Washing reduced the endosulfan residue from 15 to 28%, peeling reduced it from 60 to 67%, and cooking further lowered it from 18 to 31% in all vegetables. Dietary intake assessment revealed that only samples of okra exceeded the maximum permissible intake value at the raw stage, whereas all the other samples were below maximum permissible intake value, although some were exceeding the maximum residue limits at the raw stage.  相似文献   
14.
The effect of washing, peeling and cooking on residue levels of chlorpyrifos and 3,5,6-trichloro-2-pyridinol (TCP) in winter (spinach, cauliflower, potato) and summer vegetables (eggplant, tomato, okra) was determined. Analysis was carried out by capillary gas chromatography (DB-5MS capillary column) with mass selective detection. The samples were collected from trials conducted under controlled conditions as well as from the farmer’s field. In supervised field trials, the highest chlorpyrifos residue was found at raw stage in spinach (1.87 mg kg−1) followed by okra (1.41 mg kg−1) and eggplant (1.25 mg kg−1). The lowest residue of chlorpyrifos was recorded in cauliflower (0.036 mg kg−1). The chlorpyrifos residue reduced from 15 to 33% after washing, 65–85% post-peeling and cooking further lowered it from 12% to 48% in all the tested vegetables; while an increase in TCP concentration was observed during heat treatment. Out of 267 vegetable samples collected from the farmer’s field, 225 samples contained detectable residues representing 84% rate of contamination. About 6% of samples contained chlorpyrifos residues above maximum residue limits (MRLs). However, vegetable processing reduced the chlorpyrifos residue below the MRL.  相似文献   
15.
This paper reviews research published in recent years concerning the effects of zinc deficiency, its consequences, and possible solutions. Zinc is an essential trace element necessary for over 300 zinc metalloenzymes and required for normal nucleic acid, protein, and membrane metabolism. Zinc deficiency is one of the ten biggest factors contributing to burden of disease in developing countries. Populations in South Asia, South East Asia, and sub-Saharan Africa are at greatest risk of zinc deficiency. Zinc intakes are inadequate for about a third of the population and stunting affects 40% of preschool children. In Pakistan, zinc deficiency is an emerging health problem as about 20.6% children are found in the levels of zinc, below 60 μg/dL. Signs and symptoms caused by zinc deficiency are poor appetite, weight loss, and poor growth in childhood, delayed healing of wounds, taste abnormalities, and mental lethargy. As body stores of zinc decline, these symptoms worsen and are accompanied by diarrhea, recurrent infection, and dermatitis. Daily zinc requirements for an adult are 12–16 mg/day. Iron, calcium and phytates inhibit the absorption of zinc therefore simultaneous administration should not be prescribed. Zinc deficiency and its effects are well known but the ways it can help in treatment of different diseases is yet to be discovered. Improving zinc intakes through dietary improvements is a complex task that requires considerable time and effort. The use of zinc supplements, dietary modification, and fortifying foods with zinc are the best techniques to combat its deficiency.  相似文献   
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17.
Neural Computing and Applications - In the study, intelligent computing technique is developed for solving the nonlinear system for wire coating analysis with the bath of Oldroyd 8-constant fluid...  相似文献   
18.
Plasma spray–physical vapor deposition is a new process developed to produce coatings from the vapor phase. To achieve deposition from the vapor phase, the plasma–feedstock interaction inside the plasma torch, i.e., from the powder injection point to the nozzle exit, is critical. In this work, the plasma characteristics and the momentum and heat transfer between the plasma and powder feedstock at different torch input power levels were investigated theoretically to optimize the net plasma torch power, among other important factors such as the plasma gas composition, powder feed rate, and carrier gas. The plasma characteristics were calculated using the CEA2 code, and the plasma–feedstock interaction was studied inside the torch nozzle at low-pressure (20-25 kPa) conditions. A particle dynamics model was introduced to compute the particle velocity, coupled with Xi Chen’s drag model for nonevaporating particles. The results show that the energy transferred to the particles and the coating morphology are greatly influenced by the plasma gas characteristics and the particle dynamics inside the nozzle. The heat transfer between the plasma gas and feedstock material increased with the net torch power up to an optimum at 64 kW, at which a maximum of ~3.4% of the available plasma energy was absorbed by the feedstock powder. Experimental results using agglomerated 7-8 wt.% yttria-stabilized zirconia (YSZ) powder as feedstock material confirmed the theoretical predictions.  相似文献   
19.
Soybeans contain nutritional and medicinal properties. It is a rich source of quality proteins, phytosterols, fibers, and other biologically active compounds, notably daidzein and genistein. Soybeans provide health benefits due to their functional ingredients such as proteins, polysaccharides, and isoflavones. These functional ingredients play a vital role in the reduction of different types of cancer, cardiovascular diseases, postmenopausal problems, diabetes, and some neurodegenerative disorders. This review primarily envisages the different mechanisms involved in the therapeutic effects of soybean components as well as their contribution toward the reduction of different diseases.  相似文献   
20.
PURPOSE: The author reviews the risks of occupational exposure to HIV and provides a rationale for new postexposure guidelines for healthcare workers. OVERVIEW: Approximately 50,000 percutaneous exposures occur yearly among healthcare workers in the United States. Of these, approximately 5000 involve exposures to blood that is known to be infected with HIV. The risk of transmission after percutaneous exposure to HIV-tainted blood has been estimated to be 0.3%, but the risk may be considerably higher to the healthcare worker if any of the following is present: a deep injury; visible blood on the sharp device; a procedure that involves a needle placed in the patient's artery or vein; and a patient with advanced AIDS. The increasing resistance of HIV strains to antiretroviral therapy continues to make treatment more difficult. CLINICAL IMPLICATIONS: Postexposure prophylaxis with zidovudine may reduce the risk of occupational infection by 80%. Advances in the ability to ameliorate HIV transmission rates and to treat individuals with resistant disease through innovations in drug therapy, engineering of controls for injury prevention, and more focused postexposure evaluation offer the hope of reducing this infrequent, but dangerous, occupational threat.  相似文献   
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