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111.
112.
DEA方法在中国电力行业效益评价中的应用 总被引:2,自引:0,他引:2
王宇飞 《上海电力学院学报》2008,24(4):388-392
同时使用DEA方法的C2R模型和C2GS2模型,并借助辅助模型对中国电力行业运行效率的相对有效性进行评价.不仅可以综合评价我国电力行业的技术有效性和规模有效性,还可以分别讨论纯技术效率和规模收益问题.然后在理论上给出了将非有效决策单元调整为有效的方案.结果表明:我国只有少部分地区的电力行业运作有效,大部分地区都有待改进. 相似文献
113.
不同产地望春玉兰花蕾红外光谱及挥发性成分比较研究 总被引:4,自引:0,他引:4
采用红外光谱法、气相色谱-质谱联机分析法及文献对比法对不同产地的望春玉兰花蕾和从其中用水蒸气蒸馏提取出的挥发性成分进行了研究。结果表明,不同产地的望春玉兰花蕾化学成分有所不同,红外谱图显示,高频区的3 399 cm-1左右的强吸收波数,中频区2 000~1 200 cm-1,1 657和1 612 cm-1,指纹区1 200~700cm-1,1 037、932.86 cm-1和854.25、617 cm-1可作为区别不同产地辛夷的标准峰。其中1 657、1 612、1 037 cm-1的肩峰是有效成分含量的标志,可作为评价其质量的标准;气质联用分析和文献比较显示,正宗产地甘肃和河南产辛夷的挥发性成分中,相对质量分数较大的化合物主要是桉油精、α-松油醇、桧烯、松油烯-4-醇、桉醇类等,可用桉油精、松油醇两种主要药用成分的质量分数作为望春玉兰花蕾这一药物的质量评价标准;其他产地的桧烯、月桂烯的质量分数较大,可用桧烯、月桂烯、金合欢醇质量分数作为望春玉兰花蕾用作香料时的质量标准;GC分离时可用SE-54作分离柱。 相似文献
114.
We show how to accelerate the direct solution of the Boltzmann equation using Graphics Processing Units (GPUs). In order to fully exploit the computational power of the GPU, we choose a method of solution which combines a finite difference discretization of the free-streaming term with a Monte Carlo evaluation of the collision integral. The efficiency of the code is demonstrated by solving the two-dimensional driven cavity flow. Computational results show that it is possible to cut down the computing time of the sequential code of two order of magnitude. This makes the proposed method of solution a viable alternative to particle simulations for studying unsteady low Mach number flows. 相似文献
115.
Worldview 3是目前最先进的高分辨率光学卫星之一。针对Worldview 3遥感卫星数据全色波段和短波红外波段(Short-Wave Infrared,SWIR)空间分辨率差异大、波谱范围不一致所导致的融合结果块状效应以及空间分辨率增强效果有限的问题,提出一种两步式影像融合框架。该框架降低全色波段空间分辨率,实现与SWIR波段的初步融合;将初步融合的结果与原始分辨率全色波段进行第二步融合。通过选择6种典型像素级融合方法两两组合,形成36种融合方案,验证框架的可用性。选取包含植被、建筑、水体等典型地物类型的Worldview 3数据集进行实验,并采用五个定量评价指标进行评价。实验结果表明:使用两步式融合框架进行融合,通过渐进式空间细节注入的方式,避免了直接融合产生的块状效应,实现了短波红外影像的空间分辨率增强;第一步融合采用高通滤波(HPF)融合法,第二步融合采用GS(Gram-Schmidt Transform)变换融合方法,引入的空间信息最多,获得的融合结果质量最好。提出的融合框架既能避免块状效应的产生,又能有效增强SWIR波段的空间分辨率,对于其他卫星的全色与短波红外波段的融合也具有一定借鉴意义。 相似文献
116.
DSP在便携式多功能电能测量仪中的应用研究 总被引:3,自引:0,他引:3
测量仪器数字化是当前仪器的发展方向,文中阐述了DSP技术在电力测量中的应用。经A/D采样后的电流、电压送入DSP芯片,并进行相关处理,得到所需要的电流和电压的平均值、有功功率及功率因数等电力参数,本系统还可以通过通信模块进行远程测量和数据传输。该方案具有良好的灵活性、可升级性和高效性的特点。 相似文献
117.
为了扩展全光极化的材料范围 ,制备了以分散红 5 4为客体的 PMMA掺杂型有机聚合物薄膜样品 ,对之进行了全光极化特性的研究 ,极化使薄膜产生二阶非线性 ,种子光的强度越大 ,其二阶非线性极化率达到饱和值越快 ;种子光的位相差、相对强度比、光场强度比等因素影响薄膜的二阶非线性的优劣 相似文献
118.
The relationship between residential location, location value and accessibility has been of long interest to regional scientists. Studies investigating the relationship between house price and changes in accessibility, however, have been fewer in number, and predominantly have centered upon the house price impact of fixed rail investments. Neglected have been the impacts of smaller road investments made on a regular basis by municipalities and state departments of transportation. This research therefore reports on the spatial relationship between house price and investment in road-based transportation infrastructure by combining two spatial databases, both centered on Columbus, OH. The first contains information on all single-family detached houses sold in 1990. The second contains detailed spatial and temporal information on all accessibility-changing road investments in the same area, since 1978. Results indicate that while moderate, past, current and approved (but not begun) road investments have distinct and significant impacts on house price.An earlier version of this paper was presented at the 40th Annual Meeting of the Western Regional Science Association in Palm Springs, California, February 2001, and was awarded The Charles M. Tiebout Prize in Regional Science. Randall Jackson, Morton OKelly, W. Randy Smith, Donald Haurin, Frank Mittlebach, the editor and an anonymous reviewer all provided valuable comments on previous drafts. Research funding was provided by the E. Willard and Ruby S. Miller Fellowship and through the Committee on Urban Affairs at Ohio State.Received: March 2001/Accepted: November 2003 相似文献
119.
The present work reports an innovative approach for surface functionalisation of magnesium alloys (WE54) containing yttrium and rare-earth (RE) elements. A two-step surface modification consisting on the formation of an anodic film followed by the deposition of a hybrid silane layer obtained by dipping in a bis-[triethoxysilylpropyl]tetrasulfide silane (BTESPT) solution was performed on the WE54 alloy. 相似文献
120.
Bolesław P Salmanowicz Maria Surma Tadeusz Adamski Michał Rębarz 《Journal of the science of food and agriculture》2008,88(10):1716-1725
BACKGROUND: Knowledge of the types and amounts of individual HMW glutenin subunits (HMW-GS) is important for predicting technological quality. In this study, 228 wheat doubled haploids were compared in respect of HMW-GS composition, seed protein content, flour yield, rheological properties of dough, and loaf properties. The quantitative and qualitative composition of particular HMW-GS was determined by CE. The relative amounts of x-type and y-type subunits encoded by individual Glu-1 loci were considered. RESULTS: The results show that the amounts of some pairs x + y of HMW-GS are correlated with technological properties. The importance of quantities of particular pairs of HMW-GS for technological values depends on allele compositions in all the Glu-1 loci. Positive correlation was found between the amount of subunits Ax1, Ax2*, Bx7 + By8 or Dx5 + Dy10 and loaf volume (r = 0.215–0.618, P < 0.05). The influence of an increasing amount of Ax1 was positively correlated with dough softening (r = 0.451, P < 0.01) and negatively with dough development time (r = − 0.209, P < 0.05) and stability (r = − 0.351, P < 0.01), whereas for subunit Ax2* these associations were opposite. CONCLUSION: The results confirm the occurrence of epistatic interactions between alleles of Glu-1 loci. The effects of amounts of HMW subunits on bread-making quality should be considered only within glutenin subunit compositions. Copyright © 2008 Society of Chemical Industry 相似文献