葡萄园土壤中铜、铁、锌、锰四种金属元素的分析与研究

采用湿法消解处理样品,火焰原子吸收光谱法检测河北昌黎葡萄酒产区5 个葡萄园土壤中的铜、铁、锌、锰4 种金属元素。并对比研究3 种葡萄、葡萄酒与葡萄园土壤中铜、铁、锌、锰4 种金属元素含量的关系。对不同葡萄园和同一葡萄园种植不同品种葡萄,其土壤中金属元素含量进行差异性分析。结果显示：葡萄园地理位置和微环境及所栽培的葡萄品种、树龄和架势不同,土壤中4 种金属元素含量不同,差异性显著。铁、锌、锰3 种元素在土壤中的含量与葡萄中的含量有一定关系。赤霞珠、美乐和西拉3 种葡萄的土壤中铜、铁、锌的含量与葡萄及其葡萄酒中相对含量规律相同,而锰不同。     

焊管焊接温度观测器的参数补偿

焊接温度是焊管生产工艺中的重要参数,准确测量焊接温度对提高焊接质量和劳动生产率意义重大。分析了设计焊接温度观测器的理论依据及各焊接温度参数对测量结果的影响,得出了焊接温度的计算公式。介绍了高频直缝焊管焊接温度观测器的基本结构,用该观测器计算焊接温度简便易行。     

控流装置对板坯中间包流场优化的影响

根据相似原理,用1:3水模型研究了230 mm×130 mm板坯连铸用60 t中间包内钢水的流动特征,通过测定模型中间包内停留时间分布曲线,计算其平均停留时间及死区,活塞区和混合区的体积。结果表明,采用下挡墙开孔能有效地改善中间包内流场,得出优化后合适的钢包控流装置组合为开孔下挡墙+湍流控制器,下挡墙高133 mm,距离冲击区765 mm。优化后的中间包比原中间包平均停留时间增加了24 s,死区体积由原来的14.8%下降至6.7%。     

Micro-combined cooling,heating and power systems hybrid electric-thermal load following operation

Micro-combined cooling, heating and power (mCCHP), typically designated as less than 30 kW electric, is a technology that generates electricity at or near the place where it is used. The waste heat from the electricity generation can be used for space cooling, space heating, or water heating. The operation of mCCHP systems, while obviously dependent upon the seasonal atmospheric conditions, which determine the building thermal and power demand, is ultimately controlled by the operation strategy. Two of the most common operation strategies are to run the prime mover in accordance to either electrical or thermal demand. In this study, a mCCHP system operating following a hybrid electric-thermal load (FHL) is proposed and investigated. This operation strategy is evaluated and compared with mCCHP systems operating following the electric load (FEL) and operating following the thermal load (FTL). This evaluation and comparison is based on site energy consumption (SEC), primary energy consumption (PEC), operational cost, and carbon dioxide emission reduction (CDE). Results show that mCCHP systems operated following the hybrid electric-thermal load have better performance than mCCHP-FEL and mCCHP-FTL. mCCHP-FHL showed higher reductions of PEC, operational cost, and carbon dioxide emissions than the ones obtained for the other two operation strategies for the evaluated case.     

Structural and optical characterization of Sn incorporation in CuInS2 thin films grown by vacuum evaporation method

Structural and optical properties of non-doped and Sn-doped CuInS₂ thin films grown by double source thermal evaporation method were studied. Sn deposition time is taken between 0 and 5 min. The films were annealed at 250 °C for 2 h in vacuum after evaporation. The X-ray diffraction spectra indicated that polycrystalline CuInS₂ films were successfully obtained after annealing and no Sn binary or ternary phases are observed for the Sn time depositions less or equal to 5 min. The Sn-doped samples after annealing have bandgap energy of 1.45–1.49 eV. Furthermore, we found that the Sn-doped CuInS₂ thin films exhibit N-type conductivity after annealing.     

XML application schema matching using similarity measure and relaxation labeling

Information integration for distributed and heterogeneous data sources is still an open challenging, and schema matching is critical in this process. This paper presents an approach to automatic elements matching between XML application schemas using similarity measure and relaxation labeling. The semantic modeling of XML application schema has also been presented. The similarity measure method considers element categories and their properties. In an effort to achieve an optimal matching, contextual constraints are used in the relaxation labeling method. Based on the semantic modeling of XML application schemas, the compatible constraint coefficients are devised in terms of the structures and semantic relationships as defined in the semantic model. To examine the effectiveness of the proposed methods, an algorithm for XML schema matching has been developed, and corresponding computational experiments show that the proposed approach has a high degree of accuracy.     

线性分式不确定系统保成本控制及其鲁棒界

研究线性分式不确定系统的动态输出反馈保成本控制.采用线性矩阵不等式(LMI)方法证明了保成本控制器存在的充分必要条件等价于一个LMI可解性问题,通过该条件将求解闭环系统的成本函数上界的最小值问题转化为一个凸优化问题,利用该凸优化问题的解,得到动态输出反馈控制器的增益矩阵,并且给出了摄动参数允许最大摄动界的一种算法.     

基于WAP技术的移动电子商务平台的设计

移动电子商务消除了时间和距离的限制,使得商务活动可以随时随地进行.结合实例给出了基于WAP技术的移动电子商务平台的解决方案,介绍了该平台的功能结构设计、数据库概念结构设计及关键技术.WAP技术在移动电子商务推广应用中起到了示范作用.     

Evaluation of the mold-filling ability of alloy melt in squeeze casting

The mold-filling ability of alloy melt in squeeze casting process was evaluated by means of the maximum length of Archimedes spiral line. A theoretical evaluating model to predict the maximum filling length was built based on the flowing theory of the incompressible viscous fluid. It was proved by experiments and calculations that the mold-filling pressure and velocity are prominent influencing factors on the mold-filling ability of alloy melt. The mold-filling ability increases with the increase of the mold-filling pressure and the decrease of the proper mold-filling velocity. Moreover, the pouring temperature relatively has less effect on the mold-filling ability under the experimental conditions. The maximum deviation of theoretical calculating values with experimental results is less than 15％. The model can quantitatively estimate the effect of every factor on the mold-filling ability.     

Fuzzy metric based on the distance function of plane and its application in optimal scheduling problems

Measuring the difference between fuzzy numbers is often needed in many fuzzy optimization problems such as manufacturing system production line scheduling with uncertainty environments. In this paper, based on the distance function of plane R2 and the level importance function, we establish the UID-metric and LPID-metric of measuring the difference between fuzzy numbers, and discuss the basic properties of UID-metric and LPID-metric, and prove that fuzzy number spaces are metric spaces about UID-metric and LPID-metric if and only if the level importance function I(λ)≠0 almost everywhere on [0, 1]. Further, we discuss the convergence, separability and completeness of UID-metric and LPID-metric based on the norms of plane R2. Finally, we analyze the characteristics of UID-metric and LPID-metric by some application examples.