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燃气机热泵冷热电三联供系统热经济学分析 被引量:5
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作者 方筝 杨昭 陈轶光 《热能动力工程》 CAS CSCD 北大核心 2009年第5期597-603,共7页
采用热经济学分析法对一台燃气机热泵冷热电三联供系统进行分析,对不同转速,蒸发温度,冷凝温度和天然气价格4项影响因素条件下,子系统成本差、经济因子和总系统的经济系数的计算分析,指出了燃气机热泵冷热电三联供系统需要改进之... 采用热经济学分析法对一台燃气机热泵冷热电三联供系统进行分析,对不同转速,蒸发温度,冷凝温度和天然气价格4项影响因素条件下,子系统成本差、经济因子和总系统的经济系数的计算分析,指出了燃气机热泵冷热电三联供系统需要改进之处,针对燃气机热泵冷热电三联供系统的设计需要注意传动比的合理设置问题,并且得出了燃气机热泵冷热电三联供系统在中国具有广阔的应用空间的结论。 展开更多
关键词 冷热电三联供 燃气机热泵 热经济学 成本差 经济因子 经济系数
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Length-Based Vehicle Classification in Multi-lane Traffic Flow 被引量:1
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作者 于洋 于明 +1 位作者 阎刚 翟艳东 《Transactions of Tianjin University》 EI CAS 2011年第5期362-368,共7页
For the realtime classification of moving vehicles in the multi-lane traffic video sequences, a length-based method is proposed. To extract the moving regions of interest, the difference image between the updated back... For the realtime classification of moving vehicles in the multi-lane traffic video sequences, a length-based method is proposed. To extract the moving regions of interest, the difference image between the updated background and current frame is obtained by using background subtraction, and then an edge-based shadow removal algorithm is implemented. Moreover, a tbresholding segmentation method for the region detection of moving vehicle based on lo- cation search is developed. At the estimation stage, a registration line is set up in the detection area, then the vehicle length is estimated with the horizontal projection technique as soon as the vehicle leaves the registration line. Lastly, the vehicle is classified according to its length and the classification threshold. The proposed method is different from traditional methods that require complex camera calibrations. It calculates the pixel-based vehicle length by using uncalibrated traffic video sequences at lower computational cost. Furthermore, only one registration line is set up, which has high flexibility. Experimental results of three traffic video sequences show that the classification accuracies for the large and small vehicles are 97.1% and 96.7% respectively, which demonstrates the effectiveness of the proposed method. 展开更多
关键词 image processing background subtraction vehicle classification virtual line horizontal projection
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Effect of Substitution of Fermented Kapok Seed (Ceiba petandra) to Soybean Meal on Production and Egg Quality from Native Laying Hens
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作者 Erman Syahruddin Rita Herawaty Azhar Ibrahim 《Journal of Agricultural Science and Technology(A)》 2015年第10期833-838,共6页
This study aimed to determine the level of use of fermented kapok seed to substitute 100% soybean meal in native laying hen rations without adverse effect on laying hen production. Two hundred and forty laying hens ag... This study aimed to determine the level of use of fermented kapok seed to substitute 100% soybean meal in native laying hen rations without adverse effect on laying hen production. Two hundred and forty laying hens aged 20 weeks were used in this experiment. The completely randomized design was assigned with six treatments to replace 0, 20%, 40%, 60%, 80% and 100% of soybean meal with fermented kapok seed with four replications. The variables measured were feed intake, feed conversion and income over feed cost (gross profit), as well as variables related to egg production (hen day production and egg weight), thickness of eggshell and yolk color index for quality of eggs. Data were analyzed statistically using analysis of variance (ANOVA), and if the result shows a marked influence, it will be followed by Duncans test (DMRT). The results showed that the performance of laying hen had not been affected significantly by substituting soybean meal with fermented kapok seed. Feed intake, feed conversion and egg production is not influenced either. In summary, the use of fermented kapok seed to substitute soybean meal in the ration can be up to 100% in the diet of laying chicken. 展开更多
关键词 Fermented kapok seed (Ceiba petandra) SUBSTITUTION hen day production native laying hen.
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A comprehensive investigation of loading variance influence on fuel consumption and gas emissions in mine haulage operation 被引量:5
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作者 Soofastaei A. Aminossadati S.M. +1 位作者 Kizil M.S. Knights P. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期995-1001,共7页
The data collected from haul truck payload management systems at various surface mines show that the payload variance is significant and must be considered in analysing the mine productivity, diesel energy consumption... The data collected from haul truck payload management systems at various surface mines show that the payload variance is significant and must be considered in analysing the mine productivity, diesel energy consumption, greenhouse gas emissions and associated costs. The aim of this study is to determine the energy and cost saving opportunities for truck haulage operations associated with the payload variance in surface mines. The results indicate that there is a non-linear relationship between the payload variance and the fuel consumption, greenhouse gas emissions and associated costs. A correlation model, which is independent of haul road conditions, has been developed between the payload variance and the cost saving using the data from an Australian surface coal mine. The results of analysis for this particular mine show that a significant saving of fuel and greenhouse gas emissions costs is possible if the standard deviation of payload is reduced from the maximum to minimum value. 展开更多
关键词 Energy consumption Haul truck Surface mine Greenhouse gas emissions Cost
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An Extension of the Dimension-Reduced Projection 4DVar
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作者 SHEN Si LIU Juan-Juan WANG Bin 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第4期324-329,共6页
This paper extends the dimension-reduced projection four-dimensional variational assimilation method(DRP-4DVar) by adding a nonlinear correction process,thereby forming the DRP-4DVar with a nonlinear correction, which... This paper extends the dimension-reduced projection four-dimensional variational assimilation method(DRP-4DVar) by adding a nonlinear correction process,thereby forming the DRP-4DVar with a nonlinear correction, which shall hereafter be referred to as the NC-DRP-4DVar. A preliminary test is conducted using the Lorenz-96 model in one single-window experiment and several multiple-window experiments. The results of the single-window experiment show that compared with the adjoint-based traditional 4DVar, the final convergence of the cost function for the NC-DRP-4DVar is almost the same as that using the traditional 4DVar, but with much less computation. Furthermore, the 30-window assimilation experiments demonstrate that the NC-DRP-4DVar can alleviate the linearity approximation error and reduce the root mean square error significantly. 展开更多
关键词 data assimilation linear approximation nonlinear correction OSSE
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The Energy Efficiency Gap in Maritime Transport 被引量:2
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作者 Michele Acciaro Peter Nyegaard Hoffmann Magnus Strandmyr Eide 《Journal of Shipping and Ocean Engineering》 2013年第1期1-10,共10页
There is evidence that the shipping industry could achieve energy efficiency gains through the implementation of new technologies, with considerable reductions of fuel costs and emissions to air in the sector. Althoug... There is evidence that the shipping industry could achieve energy efficiency gains through the implementation of new technologies, with considerable reductions of fuel costs and emissions to air in the sector. Although the cost reducing effects of some new technologies are well established, companies appear reluctant to innovate despite the financial and societal benefits, as a result of what is referred to as the energy efficiency gap. The global emission impacts of the shipping industry, most notably of greenhouse gases, sulphur and nitrogen oxides are increasingly attracting the attention of regulators, non-governmental organisations and the media, and shipping companies are under pressure to find new ways to reduce their emission footprint. Understanding the determinants of the energy efficiency gap in shipping is then critical in improving the environmental profile of the industry. This paper presents the results of a survey among Norwegian shipping companies aimed at gaining a better understanding of the barriers to implementation of new cost saving technologies. The paper assesses the technical barriers that have traditionally been indicated as the main cause of the energy efficiency gap in shipping. The paper results indicate that next to technical factors, important barriers are constituted also by managerial practices and legal constraints. 展开更多
关键词 Energy efficiency gap emission reduction technologies barriers maritime transport.
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A real-time fault-tolerant scheduling algorithm with low dependability cost in on-board computer system
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作者 王培东 魏振华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第3期361-364,共4页
To make the on-board computer system more dependable and real-time in a satellite, an algorithm of the fault-tolerant scheduling in the on-board computer system with high priority recovery is proposed in this paper. T... To make the on-board computer system more dependable and real-time in a satellite, an algorithm of the fault-tolerant scheduling in the on-board computer system with high priority recovery is proposed in this paper. This algorithm can schedule the on-board fault-tolerant tasks in real time. Due to the use of dependability cost, the overhead of scheduling the fault-tolerant tasks can be reduced. The mechanism of the high priority recovery will improve the response to recovery tasks. The fault-tolerant scheduling model is presented simulation results validate the correctness and feasibility of the proposed algorithm. 展开更多
关键词 on-board computer system fault-tolerant scheduling dependability cost PRIORITY
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Mapping Customer-Supplier Relationships
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作者 Fawzy Soliman 《Journal of Modern Accounting and Auditing》 2011年第12期1436-1445,共10页
This paper proposes that organizational performance improvement could be achieved through improving the relationship between suppliers and customers. Accordingly, the paper proposes that performance could be improved ... This paper proposes that organizational performance improvement could be achieved through improving the relationship between suppliers and customers. Accordingly, the paper proposes that performance could be improved by properly managing differences (gaps) that are usually found between customers' expectations and of suppliers perception with respect to services delivered. The paper also proposes that gaps in the relationship between customers and suppliers could be analyzed using mapping techniques. The paper points to the possibility of finding perception gaps and expectation gaps in the interrelated value attributes of goods and/or services; namely quality, cost, and time of delivery of goods or services to customers. In addition, the paper suggests that those gaps may impact on the performance from the perspectives of quality, cost, and speed of delivery of the service. It is envisaged that this research could assist management in controlling cost and avoid wastage and improve organizational performance. 展开更多
关键词 management of customers' expectations management of suppliers' perception management of gapanalysis
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Revised regional importance measures in the presence of epistemic and aleatory uncertainties
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作者 CHENG Lei LU ZhenZhou WU DanQing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第1期84-94,共11页
Two revised regional importance measures(RIMs),that is,revised contribution to variance of sample mean(RCVSM)and revised contribution to variance of sample variance(RCVSV),are defined herein by using the revised means... Two revised regional importance measures(RIMs),that is,revised contribution to variance of sample mean(RCVSM)and revised contribution to variance of sample variance(RCVSV),are defined herein by using the revised means of sample mean and sample variance,which vary with the reduced range of the epistemic parameter.The RCVSM and RCVSV can be computed by the same set of samples,thus no extra computational cost is introduced with respect to the computations of CVSM and CVSV.From the plots of RCVSM and RCVSV,accurate quantitative information on variance reductions of sample mean and sample variance can be read because of reduced upper bound of the range of the epistemic parameter.For general form of quadratic polynomial output,the analytical solutions of the original and the revised RIMs are given.Numerical example is employed and results demonstrate that the analytical results are consistent and accurate.An engineering example is applied to testify the validity and rationality of the revised RIMs,which can give instructions to the engineers about how to reduce variance of sample mean and sample variance by reducing the range of epistemic parameters. 展开更多
关键词 revised rims sample mean sample variance variance reduction analytical solution
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