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排序方式: 共有263条查询结果,搜索用时 31 毫秒
81.
82.
The performance of a masonry animal feed solar cooker was evaluated in terms of energy and exergy. It is a low-cost cooker made of cement, bricks, glass covers and a mild steel absorber plate. The energy and exergy efficiencies of the animal feed solar cooker were experimentally evaluated. The energy output of this cooker ranges from 1.89 to 49.4 kJ, whereas the exergy output ranges from 0.11 to 2.72 kJ during the same time interval. The energy efficiency of the cooker varies between 1.12% and 29.78%, while the exergy efficiency varies between 0.07% and 1.52 % during the same period. 相似文献
83.
The renewable energy sources are accompanied by certain constraints as reliability, availability and continuous generation. In India, biomass is considered as the second best suitable combination with other renewable energy sources. Both solar and wind are undependable renewable energies as they are unpredictable. Now the key to successful renewable energy harvesting lies in the selection of hybrid system architecture for power generation. In rural areas, light is usually unavailable and if it does, it is mostly an incandescent light used for household lighting instead of fluorescent. System reliability, economy and environmental issues are the three major issues for decentralised electrification. So, finding the best suited hybrid system configuration to overcome these constraints is the need of the hour. It is at this stage that HOMER comes into the picture. HOMER, abbreviated name of hybrid optimization model for electric renewable, successfully realises system configuration before its installation and works for on-grid, off-grid and stand-alone systems, which make it useful for rural to urban applications. It simulates and optimises the best suitable solution for a hybrid system and generates reports incorporating all the aspects in designing a system. Here, a typical hybrid system is considered and the implementation of HOMER software has been incorporated. 相似文献
84.
Immobilization of amyloglucosidase on polystyrene anion exchange resin I. preparation and properties
Amyloglucosidase (exo‐1,4‐ α‐D‐glucosidase, E C 3.2. 1.3) was coupled to glutaraldehyde activated Indion 48‐R (a cross‐linked macroporous anion exchanger) by Schiff base reaction. The bound enzyme exhibited 60–70% activity of the free enzyme. Substrate concentrations as high as 32% (w/w) liquefied tapioca starch could be quantitatively converted into 96–98% (w/w) dextrose in 24 h at 50°C and pH 4.5. Though immobilization lowered the temperature optimum to 50–60°C from 65°C for the free enzyme, it increased the temperature stability. However, there was no change either in the pH optimum or pH stability after immobilization. In batch operations, the immobilized preparation showed a half life of 32 and 12 days at 50°C and 60°C respectively. 相似文献
85.
Raju Seenivasan Rengasamy Vijay Kumar Kothari Vijay S. Bele Rajesh Khanna 《纺织学会志》2013,104(12):1019-1030
In this paper, spunbond, meltblown and spunbond–meltblown–spunbond (SMS) nonwovens made from polypropylene are analysed for liquid transport behaviour. The thickness, grams per square metre (GSM), porosity, fibre diameter, fibre orientation distribution and water contact angles of these nonwovens are measured. Vertical wicking with decane using tensiometry and water absorbency and spreading using gravimetric absorbency tester are reported. The equivalent pore radii of the nonwovens are deduced from the vertical sorption experiments using tensiometry. The sorption rate under vertical wicking and water spreading rates are faster along machine direction compared with that in cross‐direction due to preferential fibre orientation. The thickness of the nonwoven, fibre diameter and porosity play a vital role in transporting liquid. Thin nonwovens have poor vertical wicking and spreading rate. SMS web has poor absorbency behaviour mainly due to the inability of its top S‐layer to pull the liquid from the middle M‐layer. The measured water spreading lengths with respect to time are compared to the theoretical ones using a model developed by earlier researchers. This model reasonably predicts the spreading behaviour of nonwovens. 相似文献
86.
Ashish Agrawal Raj Kumar Vishwakarma Vineet R. Tripathi Anil K. Kothari Bindeshwar Prasad Jitesh Kumar 《钢铁冶炼》2013,40(4):373-382
The key to excellent casthouse operation are low cost, high productivity, dry hearth and high casting rate while minimising the consumable material. The stable blast furnace operation requires proper control of drainage rate of liquid hot metal and slag from hearth. The productivity of blast furnace can be effectively increased if drainage rate is considerably increased. If the drainage rate is controlled, the periodic tapping of hot metal and slag from hearth can be made effective. This paper highlight the improvement made in casting practice by controlling the hearth liquid level in blast furnace. The improvements have made significant change in casthouse management. It is well demonstrated that various casthouse operations have migrated from one regime of operation to another regime and various consumable items are significantly reduced. The importance of increasing the drainage rate in improving the productivity of blast furnace is explained in details. 相似文献
87.
A Probabilistically Robust Path Planning Algorithm for UAVs Using Rapidly-Exploring Random Trees 总被引:1,自引:0,他引:1
The computationally efficient search for robust feasible paths for unmanned aerial vehicles (UAVs) in the presence of uncertainty is a challenging and interesting area of research. In uncertain environments, a “conservative” planner may be required but then there may be no feasible solution. In this paper, we use a chance constraint to limit the probability of constraint violation and extend this framework to handle uncertain dynamic obstacles. The approach requires the satisfaction of probabilistic constraints at each time step in order to guarantee probabilistic feasibility. The rapidly-exploring random tree (RRT) algorithm, which enjoys the computational benefits of a sampling-based algorithm, is used to develop a real-time probabilistically robust path planner. It incorporates the chance constraint framework to account for uncertainty within the formulation and includes a number of heuristics to improve the algorithm’s performance. Simulation results demonstrate that the proposed algorithm can be used for efficient identification and execution of probabilistically safe paths in real-time. 相似文献
88.
89.
Functional oligosaccharides have emerged as valuable components of food and dietary supplements. Their resistance to digestion and fermentation by colonic microbes has given them the nutritional edge. Apart from implications as dietary fibers, sweeteners, and humectants, they are hailed as prebiotics. Their beneficial effects extend from antioxidant, anti‐inflammatory, immunomodulatory, antiallergic, hypotensive, hyperlipemic, neuroprotective to anticancer. The rising popularity of bioactive oligosaccharides has accelerated the search for their generation from new, sustainable sources. The surfacing crucial role in healthcare and unprecedented demand necessitates deeper investigation. The present review embodies an overview on various aspects of production, properties with emphasis on therapeutic applications of functional oligosaccharides. The biological efficacy and possible mechanisms of action of oligosaccharides have also been discussed. 相似文献
90.
Saravanan Vijayalakshmi Alagan Anpalagan D. P. Kothari Isaac Woungang Mohammad S. Obaidat 《The Journal of supercomputing》2014,68(3):1265-1279
The study and development of chip multi-processors (CMPs) are of utmost importance for the creation of future technologies. Devising a theoretical analysis of the micro-architecture model for the power/performance on CMPs is still a challenge. This paper addresses this problem by (1) introducing an analytical model for measuring the power and performance of a processor quantitatively, (2) analyzing the effects of resource division on power consumption and performance when executing a given benchmark, and (3) predicting the optimum number of cores to run the benchmark on. Our proposed analytically derived results show that in order to achieve power/performance gains, the optimum number of cores must be between 8 and 16. 相似文献