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31.
This paper describes the fabrication, experimentation and simulation stages of converting a 165 l domestic electric refrigerator to a solar powered one. A conventional domestic refrigerator was chosen for this purpose and was redesigned by adding battery bank, inverter and transformer, and powered by solar photovoltaic (SPV) panels. Various performance tests were carried out to study the performance of the system. The coefficient of performance (COP) was observed to decrease with time from morning to afternoon and a maximum COP of 2.102 was observed at 7 AM. Simulations regarding economic feasibility of the system for the climatic conditions of Jaipur city (India) were also carried out using RETScreen 4. It was observed that the system can only be economically viable with carbon trading option taken into account, and an initial subsidy or a reduction in the component costs – mainly SPV panels and battery bank. 相似文献
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Simultaneous sequestration of nitrate and phosphate from wastewater using a tailor‐made bacterial consortium in biofilm bioreactor
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Pallavi Mukherjee Chaitali Chanda Moumita Bhaumik Madhurima Ghosh Jaweria Sharmin Poulami Datta Srimoyee Banerjee Parthasarathi Barat Ashoke Ranjan Thakur Lalit Mohan Gantayet Indranil Mukherjee Shaon Ray Chaudhuri 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2018,93(5):1279-1289
34.
Shahabi C. Ghandeharizadeh S. Chaudhuri S. 《Knowledge and Data Engineering, IEEE Transactions on》2002,14(2):447-455
In multiuser multimedia information systems (e.g., movie-on-demand, digital-editing), scheduling the retrievals of continuous media objects becomes a challenging task. This is because of both intra and inter lobject time dependencies. Intraobject time dependency refers to the real-time display requirement of a continuous media object. Interobject time dependency is the temporal relationships defined among multiple continuous media objects. In order to compose tailored multimedia presentations, a user might define complex time dependencies among multiple continuous media objects with various lengths and display bandwidths. Scheduling the retrieval tasks corresponding to the components of such a presentation in order to respect both inter and intra task time dependencies is the focus of this study. To tackle this task scheduling problem (CRS), we start with a simpler scheduling problem (ARS) where there is no inter task time dependency (e.g., movie-on-demand). Next, we investigate an augmented version of ARS (termed ARS+) where requests reserve displays in advance (e.g., reservation-based movie-on-demand). Finally, we extend our techniques proposed for ARS and ARS+ to address the CRS problem. We also provide formal definition of these scheduling problems and proof of their NP-hardness 相似文献
35.
Sripati Ranjan Chaudhuri 《International Journal of Engineering Science》1979,17(12):1273-1281
Starting with a class of small deformations superposed on a finitely deformed state of a transversely isotropic elastic solid, we study a problem of small torsional vibration superposed on homogeneous finitely deformed state of a circular cylindrical rod made of transversely isotropic elastic material. It has been found that free vibration is possible and, due to anisotropy, the speed of propagation of waves of torsion along the cylinder is increased or decreased according as the initial stressed state is under tension or compression. 相似文献
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The paper describes the implementation of a centralised control-design scheme in a real-time laboratory-based dynamic simulator. A centralised multivariable-control algorithm is designed employing remote feedback signals considering delay in signal transmission. The transmitted signals can be used for multiple-swing-mode damping using a single controller. Such an algorithm is numerically intensive owing to the high controller size and the predictor that takes care of the delay in signal transmission. The performance of the proposed controller is demonstrated by practical implementation using a rapid-prototyping controller mounted on a PC-ATX. Results of the experimental tests are shown for a detailed model of the power system implemented using Linux PC-based multiprocessor technology. 相似文献
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Appreciable difference in the properties of undoped and oxide-doped mullite are observed. The oxidation state of cation, its concentration and the position of the mullite lattice occupied by it appear to be the responsible factors. Mullite has, therefore, been doped with four transition metal ions, Mn, Fe, Cr and Ti. With the help of EPR and Mössbauer spectroscopy (supplimented by X-ray diffractometry) the oxidation states of these ions and the mullite lattice sites where they enter has been investigated. It was observed that Mn ion was present in Mn2+ and Mn3+ states, the former remained as clusters and the latter occupied the octahedral sites in the mullite lattice. Only Fe3+ ion was detected and conclusive evidence was obtained for the entry of Fe3+ in the octahedral lattice position of mullite from the analysis of Mössbauer spectra with the help of a specially written computer programme. The Cr ion entered the mullite structure only in the Cr3+ state. The change in lattice parameters of Cr doped mullite were measured by the XRD technique. The results showed that the expansion of b-axis was more than that of the a-axis which supported the presence of Cr3+ ion in the octahedral site of mullite lattice. The absence of signal in the EPR spectra of Ti doped mullite suggested the presence of only Ti4+ (3d0) ion. Very low electrical resistivity of Ti doped mullite and close similarity between mullite and Al2TiO5 structures stood as evidence for incorporation of Ti4+ ion in the octahedral site of mullite lattice by replacing Al3+ ion. 相似文献
40.
The growth and microstructure of Cd1–x
Zn
x
S films were studied by depositing the films on to freshly cleaved NaCl, KCl, and LiF substrates at various x values (0相似文献