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A new matching cost computation method based on nonsubsampled contourlet transform (NSCT) for stereo image matching is proposed in this paper. Firstly, stereo image is decomposed into high frequency sub-band images at different scales and along different directions by NSCT. Secondly, by utilizing coefficients in high frequency domain and grayscales in RGB color space, the computation model of weighted matching cost between two pixels is designed based on the gestalt laws. Lastly, two types of experiments are carried out with standard stereopairs in the Middlebury benchmark. One of the experiments is to confirm optimum values of NSCT scale and direction parameters, and the other is to compare proposed matching cost with nine known matching costs. Experimental results show that the optimum values of scale and direction parameters are respectively 2 and 3, and the matching accuracy of the proposed matching cost is twice higher than that of traditional NCC cost. 相似文献
3.
《Energy Policy》2015
In this paper we construct an indirect measure of the supply marginal cost function for the main generators from the observed bid data in the Italian electricity market in the period 2004–2007. We compute the residual demand function for each generator, taking explicitly into account the issue of transmission line congestion. This procedure allows recovering correct zonal Lerner index and the implied measure of the marginal cost function. We find evidence of a stable U-shaped marginal cost function for three main Italian generators, but a flat function for ENEL, the former national monopolist. The policy relevance of our approach lies in the possibility to offer some empirical knowledge of the marginal cost function of each generator to the regulator to design appropriate policy measures geared to the promotion of competitive market conditions. We propose a new market surveillance mechanism, which is based on the principle of sanctioning excessive deviations from the estimated measure of the marginal cost function presented in this work. 相似文献
4.
This study is to evaluate the potential for development of a cellulosic ethanol facility in Vietnam. Rice straw is abundant in Vietnam and highly concentrated in the Mekong Delta, where about 26 Mt year−1 of rice straw has been yearly produced. To minimize the overall production cost (PC) of ethanol from rice straw, it is crucial to choose the optimal facility size. The delivered cost of rice straw varied from 20.5 to 65.4 $ dry t−1 depending on transportation distance. The Mekong Delta has much lower rice straw prices compared with other regions in Vietnam because of high density and quantity of rice straw supply. Thus, this region has been considered as the most suitable location for deploying ethanol production in Vietnam. The optimal plant size of ethanol production in the region was estimated up to 200 ML year−1. The improvement in solid concentration of material in the hydrothermal pre-treatment step and using residues for power generation could substantially reduce the PC in Vietnam, where energy costs account for the second largest contribution to the PC, following only enzyme costs. The potential for building larger ethanol plants with low rice straw costs can reduce ethanol production costs in Vietnam. The current estimated production cost for an optimal plant size of 200 ML year−1 was 1.19 $ L−1. For the future scenario, considering improvements in pre-treatment, enzyme hydrolysis steps, specific enzyme activity, and applying residues for energy generation, the ethanol production cost could reduce to 0.45 $ L−1 for a plant size of 200 ML year−1 in Vietnam. These data indicated that the cost-competitiveness of ethanol production could be realized in Vietnam with future improvements in production technologies. 相似文献
5.
随着BIM技术的进步,建筑行业越来越重视BIM技术的应用,并在应用过程中取得一定的成效。本文从工程造价决策、设计、招投标、施工、竣工五个阶段阐述BIM技术在建筑工程造价中的应用对策。 相似文献
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降低成品油二次物流运输成本的思考 总被引:4,自引:0,他引:4
介绍了传统成品油进货和管理模式存在的诸如成品油物流以行政区划、中问环节多、信息化程度不高、运输路线未优化造成物流成本提高等问题。提出要降低成品油二次物流运输成本,当务之急是加强成品油物流的信息化建设;调整管理模式,打破行政区域界限,开展经济辐射半径内的库站物流配送;引进竞争机制,打破运输垄断,一、二次物流结合,大、小车型搭配,提高运营效率;做好运杂费全面预算、核算及运行费用的过程控制。 相似文献
8.
文章介绍了在windows2000环境下通过编写WDM(Windows Driver Model)设备驱动程序实现实时数据采集和控制的一种方法。采用研华数据采集卡PCL818L产生中断信号.通过编写WDM驱动程序实现了在windows2000环境下转台的位置控制。并在实验中调试通过。实验结果表明:在采样频率为1KHz的情况下。控制系统很好实现了输出对输入的跟踪,证明了采用方法的正确性。该方法解决了windows2000环境下的实时性问题,为在windows环境下实时控制系统的实现提供了有益的尝试。 相似文献
9.
试论循环水装置的经济性及其成本分析 总被引:2,自引:1,他引:1
通过对循环水装置的投资和成本分析,阐述了建设该装置的经济性和社会意义。 相似文献
10.
涡轮钻具在高陡构造的应用及展望 总被引:1,自引:1,他引:0
介绍了涡轮钻具在秋参1井的应用情况,详细叙述了涡轮钻具在山前高陡构造快速钻进及防斜打直方面的优点,与常规钻井相比,机械钻速明显提高,钻井周期明显缩短,钻井成本明显下降,经济效益显著。 相似文献