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81.
A personal-computer based model of an Integrated Energy System for Industrial Estates (IESIE) has been developed as a pre-feasibility tool: it addresses the total energy concept by combining a set of CHP plant(s), boilers, vapor-compression and absorption chillers, national grid and utility transportation system. The core of the general model is the linear programming (LP) model which takes into account the changing demand-pattern of various loads and their tariffs, standby charge of electricity, unit fuel price, equipment costs, land cost, depreciation, O & M expenses, interest rate, taxes, etc. The output of the LP model yields the minimum total operating cost, optimal sizes of the equipment and their respective operational schedules. The hot utility and cold utility transportation model estimates the economic-minimum pipe size, considering installation cost, heat loss/gain cost and pumping cost. The heat balance model finds the thermal cycle equipment sizes as well as the variation of the heat-to-power ratio with load. Finally the economic model does the cash-flow analysis to determing whether the project will yield a required rate-of-return to be economically viable.

Simulations have been done using the model considering a number of sample load patterns with the prevailing cost factors in India. An after tax IRR of 20% was found for sites having load factors greater than 0·6, and up to 10 km utility transportation distance.  相似文献   

82.
In this communication we propose a method to implement an all-optical astable multivibrator using the non-linear material based switches and logic gates. The scheme can operate in real time. The delay time can achieve ps(pico-second). The pulse duration can be made very low and may cross the THz easily by selecting proper material and laser source.  相似文献   
83.
Ternary cobalt-nickel silicide thin films were synthesized by DC magnetron sputtering from an equiatomic cobalt-nickel alloy target. Grazing incidence XRD, Rutherford back scattering, high-resolution cross-sectional TEM analysis and electrical study were carried out to investigate the formation of silicide, stoichiometry, film thickness, depth profile and sheet resistance of as-deposited and post-deposition annealed films. The ternary silicide layer thickness was calculated from RBS simulated data, which was found to vary 20-43 nm for as-deposited and different vacuum annealed films. A minimum value of sheet resistance 2.73 Ω/sq corresponding to a resistivity of ∼8.4 μΩ-cm was obtained for optimized deposition and annealing conditions.  相似文献   
84.
This paper presents the application of self-sensing actuation (SSA) to facilitate the implementation of piezoelectric actuator in an intelligent mechatronic system. SSA is a technique to employ smart materials, such as piezoelectric materials, simultaneously as a sensor and an actuator; thereby increasing the level of integration of the system. The piezoelectric actuator is equipped with an exclusive adaptive controller amidst its nonlinearities and system's disturbance. The application area to be discussed is a microdispensing system, which is an example of a micromanufacturing process, combining a fluidic system and a positioning system.  相似文献   
85.

BaZrO3 doped (Na0.52K0.48)(Nb0.95Sb0.05)O3 ceramics were prepared using solid state route. The optimization of processing parameters like calcination temperature (800 °C), sintering temperature (1140 °C) and poling parameters (3 kV/mm at 120 °C/60 min) was carried out on base composition. Optimized parameters yielded a piezoelectric charge coefficient of 171 pC/N in composition having 4 mol% BaZrO3. Low temperature dielectric measurements and high temperature X-ray diffraction studies, along with structural refinement using Rietveld method were performed to ascertain the new found phenomenon. A castling-like phenomenon was observed in (1-x)(Na0.52K0.48)(Nb0.95Sb0.05)O3xBaZO3 (0.00?≤?x?≤?0.08) ceramics, where two phases interchanged their position. Also, BaZrO3 led to negative ageing behavior in these ceramics. Doping of BaZrO3 improved the electrical fatigue behavior and degraded the ferroelectric and thermal stability of ceramics.

  相似文献   
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This paper presents the material design and fresh properties of geopolymer mortar developed for 3D concrete printing application. Unlike traditional casting, in 3D printing, extruded materials are deposited layer-by-layer to build complex architectural and structural components without the need of any formwork and human intervention. Extrudability, shape retention, buildability and thixotropic open time (TOT) are identified as critical early-age properties to characterize the 3D printable geopolymer material. Five different mix designs of geopolymer are tested in a systematic experimental approach to obtain a best printable mix and later it is used to print a 60-centimeter-tall freeform structure using a concrete gantry printer to validate the formulation.  相似文献   
89.
The current article discussed the detail design and development of an experimental test rig to derive usable energy by utilizing the waste heat energy through a heat exchanger made of Bi2Te3 material. The accuracy including the efficiency of the fabricated device is demonstrated further by verifying the associated parameter through a simulation model (commercial finite element package, ANSYS 15.0). To imitate the waste hot air from the industry is achieved via a heat gun and fed to the test rig for the generation of thermoelectric power. The simulation model accuracy has been demonstrated by juxtaposing the associated experimental data and computational readings. Subsequently, the feasibility and optimum range of design parameters are established by comparing the experimental and the simulation data (triggered temperature difference, voltage output, and heat flux) generated at the interface of the thermoelectric power generators. In addition, the coefficient of determination (R2) value has been evaluated statistically and verified with the current experimental results for the demonstration of the relevancy. The statistical study shows the existence of the correlation between the current experimental and the simulation model. Also, the experimental result indicates the possible implementation of the newly developed system for the recovery from the waste heat either the automobile exhaust or any other kind of dissipated heat from the industries.  相似文献   
90.
Recently, the sparse representation (SR) based algorithms have gained much attention from the researchers in the area of image fusion (IF). The building of a compact discriminative dictionary plays a vital role in the sparse-based IF techniques. In this context, an efficient multimodal IF method based on improved dictionary learning is investigated. The key contributions of this paper are: (a) An improved KSVD algorithm is suggested for the dictionary learning process, (b) to reduce the computational time, only the informative patches are selected using energy feature, and (c) a novel region-based fusion scheme is suggested for the first time for the problem on hand. The suggested technique is tested with a number of multimodal images from Harvard Medical School brain database. The results are compared with state-of-the-art multiscale transform-based methods and modified SR-based methods. Unlike earlier methods, our proposed technique generates an adaptive dictionary through selection of informative patches only. This results in a compact dictionary with improved computational efficiency. The experimental results reveal that our approach outperforms other methods. The potential application of the suggested method could be in pathological images for follow-up study and better treatment planning.  相似文献   
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