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21.
In this study, wind characteristics were analyzed using the wind speed data collected of the six meteorological stations in Turkey during the period 2000–2006. The annual mean wind speed of the six stations (Erzurum, Elaz??, Bingöl, Kars, Manisa and Ni?de) is obtained as 8.7, 8.5, 5.9, 6.9, 7.4 and 8.0 m/s at 10 m height, respectively. The mean annual value of Weibull shape parameter k is between 1.71 and 1.96 while the annual value of scale parameter c is between 6.81 and 9.71 m/s. A technical assessment has been made of electricity generation from four wind turbines having capacity of (600 kW, 1000 kW, 1500 kW and 2000 kW). The yearly energy output and capacity factor for the four different turbines were calculated.  相似文献   
22.

The diagenetic history of the Upper Eocene volcaniclastic rocks of the Thrace Basin is described based on petrological analysis of samples from six boreholes. Diagenesis in the volcaniclastic rocks principally involves the progressive development of various types of cements in the following order: quartz overgrowth, zeolite authigenesis, chlorite and illite authigenesis. After the formation of the cementation phases, there is a dissolution phase creating secondary porosity via the dissolution of volcanic class and feldspars, accompanied by generation of analcime and a late mordenite cementing phase. The volcaniclastic rocks also have been affected by the following diagenetic processes: fracturing and calcite, quartz, and zeolite cementation.  相似文献   
23.
In this work, the inverse scattering problem for Dirac equations system with discontinuous coefficient and higher order polynomials of spectral parameter in the boundary condition is considered. The scattering function of the problem is defined, and its properties are investigated. The Marchenko-type main equation is obtained and it is shown that the potential is uniquely recovered by the scattering function. A generalization of Marchenko method is given for a class of Dirac operator.  相似文献   
24.
Universal Access in the Information Society - This study thoroughly examines the usability of digital materials, to establish a classroom environment in which technology is integrated into teaching...  相似文献   
25.
土壤重金属铅污染作为现代工矿业发展的产物,已逐渐入侵到农业生产和农产品中。高光谱技术由于具有宏观、快速、高效的特点已成为土壤重金属监测的重要手段。以新疆吐鲁番盆地葡萄园土壤Pb元素为研究对象,分析土壤原始光谱在内的15种光谱变换下的土壤光谱反射率数据与土壤Pb含量的关系,构建土壤Pb含量偏最小二乘回归(PLSR)模型和地理加权重回归(GWR)模型,对比分析并探讨运用土壤高光谱估算葡萄园土壤Pb含量的可行性。结果表明:土壤原始光谱反射率通过光谱变换能有效增强葡萄园土壤Pb元素的光谱特征及模型估算精度,其中,平方根二阶微分(SRSD)变换的PLSR模型和GWR模型估算能力最优。采用GWR模型比PLSR模型更好的解释葡萄园土壤重金属Pb含量高光谱估算。从模型稳定性和精确性来看,在平方根二阶微分变换中GWR模型R2从PLSR模型的0.262提高至0.866, 平方根误差减少了1.009。采用GWR模型可有效提高估算葡萄园土壤Pb含量的精度,为中国葡萄园基地土壤重金属污染以及土壤环境安全研究提供有益借鉴。  相似文献   
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27.
Forecasting streamflow mainly due to snowmelt in the mountainous eastern part of Turkey is important in terms of effective management of water resources at the headwaters of Euphrates River, where large dam reservoirs are located. Monitoring Snow Covered Area (SCA) and modeling snowmelt forms the backbone of the forecasting studies as the snowmelt dominating runoff constitutes approximately 2/3 of total annual volume of runoff during spring and early summer. Two main motivations of the study are; firstly, to assess the methodologies to forecast SCA using Moderate Resolution Imaging Spectroradiometer (MODIS) data and derive Snow Depletion Curve (SDC) for each elevation zone. Secondly, to forecast 1?day ahead daily discharges using the derived SDCs and Numerical Weather Prediction (NWP) data corrected specifically for the area. The Upper Euphrates Basin (10,275?km2) is selected as the pilot basin and MODIS daily snow cover products are analyzed for the snowmelt season. Four different methodologies are proposed and assessed to forecast SDCs; simple averaging, temperature based, stochastic modeling and probabilistic approach. SDCs are derived for the water years 2006?C2010, 4?years data are used to derive the equations of the methodologies and 1?year is used to verify their skills. Forecasting discharges 1?day ahead with Snowmelt Runoff Model using NWP data is the second part of the study. Impact of forecasted SDCs with different methodologies is examined with the model. Model applications provide promising results both for the forecasting of SCA and runoff with an overall Model Efficiency higher than 0.60 and 0.85, respectively.  相似文献   
28.
In this study, the bacteria which were isolated from various milk and fermented food products were tested for their ability to convert metmyoglobin to nitrosomyoglobin. Lactic acid bacteria were isolated from samples of raw milk, unsalted butter, Beyaz cheese, yoghurt, pickles and silage. The nitric oxide (NO) forming abilities of 1534 isolates were tested using plates of de Man, Rogosa, Sharpe agar supplemented with metmyoglobin (MRS-Mb). Ten isolates formed bright red colonies, brown or clear zones due to the conversion of metmyoglobin to nitrosomyoglobin were identified. Five of the 10 bacteria were identified as Lactobacillus plantarum, three as Pediococcus acidilactici, and two as Leuconostoc mesenteroides subsp. dextranicum. NO formation ability was measured in MRS-Mb broth. There were differences not only among the species, but also among the strains of a species. The highest NO concentrations of 51.5, 51.3, 50.2 μM were produced by P. acidilactici S2, L. plantarum T119, and P. acidilactici S3, respectively.  相似文献   
29.
研究基于蓄电池、熔盐储热、抽水蓄能及储氢技术经济性比较的可再生能源发电系统多目标容量优化。该容量优化模型以最小化平准化度电成本及失负荷率为目标,应用4种代表性多目标进化算法进行求解。提出基于超体积的多目标算法综合评价指标,此外考虑了储能运行特性及资源不确定性提高仿真计算的准确性。算法性能比较结果表明,非劣排序遗传算法的平均排序等级为1.6,其具有最优的综合性能;储能的定量技术经济性比较结果表明,不同可靠性条件下熔盐储热系统的经济性均为最优;不同负荷曲线及不同资源水平的敏感性分析验证了储能经济性比较结果的有效性。  相似文献   
30.
为进一步研发溶剂法制备纤维素薄膜的新工艺,以LiCl/DMAc为纤维素溶剂,溶解棉浆粕得到均匀透明的纤维素LiCl/DMAc溶液,采用湿法工艺制备纤维素薄膜.用红外光谱、扫描电镜及X射线衍射等分析方法对薄膜结构进行表征.考察制膜液中纤维素浓度、凝固浴种类、凝固浴中LiCl/DMAc浓度及凝固浴温度对薄膜力学性能的影响,...  相似文献   
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