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101.
102.
Ingo Alig Dirk Lellinger Harald Oehler Sergey A. Adamovsky Christoph Schick 《Progress in Organic Coatings》2008,61(2-4):166-175
A new microcalorimeter with eight parallel channels using robust, low cost sensors for characterization of coatings and adhesives is described and first experiments on coatings and adhesives are presented. The calorimetric sensors are based on thin glass plates (20 mm × 20 mm, thickness 150 μm) with heater and thermocouple sputtered on the surfaces (calorimetric active area of about 9 mm2). The setup allows heating and cooling experiments as well as isothermal measurements in the temperature-modulated mode with up to eight sensors in parallel. The measured quantities are the real (C′p) and imaginary part (C″p) of the complex heat capacity (), the related absolute value of the heat capacity () and the heat flow . An industrial computer (NI PXI system) with specific software for calibration and data recording controls the electronic components. Sensors can be embedded in a temperature controlled oven (heating and cooling by Peltier elements) or alternatively in a climatic cabinet with controlled temperature and humidity.
The method has been applied successfully to monitoring of film formation of aqueous polymer dispersions (styrene-acrylate copolymer) and curing of coatings. 相似文献
103.
浆砌石衬砌在渠道防渗中的应用及对策 总被引:2,自引:0,他引:2
总结了浆砌石应用的历史,介绍了浆砌石的结构特性和施工工艺,从造价方面、防渗效果及施工三方面分析了浆砌石衬砌主要存在的问题,并提出了相应的解决对策,指出浆砌石衬砌在渠道防渗应用中应控制施工质量,从而更好地提高防渗效果。 相似文献
104.
凤滩水电厂自动发电控制策略 总被引:1,自引:0,他引:1
介绍了凤滩水电厂自动发电控制(AGC)策略的实现方法,重点介绍了修正等容量比例有功分配方法及相应措施.程序设计的原则是,机组紧跟目标负荷的情况下,在最佳效率下运行,同时减少机组开/停机次数、有功调节频率和跨越振动区次数,从而减少机组磨损,兼顾运行效率和机组运行安全. 相似文献
105.
In today's competitive business environment, it is important that customers are able to obtain their preferred items in the shops they visit, particularly for convenience store chains such as 7–Eleven where popular items are expected to be readily available on the shelves of the stores for buyers. To minimize the cost of running such store chains, it is essential that stocks be kept to a minimum and at the same time large varieties of popular items are available for customers. In this respect, the replenishment system needs to be able to cope with the taxing demands of minimal inventory but at the same time keeping large varieties of needed items. This paper proposes a replenishment system which is able to respond to the fluctuating demands of customers and provide a timely supply of needed items in a cost–effective way. The proposed system embraces the principle of fuzzy logic which is able to deal with uncertainties by virtue of its fuzzy rules reasoning mechanism, thereby leveraging the responsiveness of the entire replenishment system for the chain stores. To validate the feasibility of the approach, a case study has been conducted in an emulated environment with promising results. 相似文献
106.
Methane/natural gas storage and delivered capacity for activated carbons in dry and wet conditions 总被引:1,自引:0,他引:1
Methane/natural gas storage and delivered capacity for three different activated carbons in dry and wet conditions were measured. In all tests the temperature of the bed was maintained constant at 277.15 K and pressure was increased up to 10 MPa. Natural gas storage capacity was less than methane storage capacity in dry conditions for all the three activated carbons tested, while the gas delivery was almost the same. One of activated carbon tested (NC120) showed the possibility of hydrate forming for pressures higher than 4 MPa but the amount of gas stored still was less than the amount stored in dry conditions over the whole range of pressure. The analysis of the gas delivered at each pressure steps shows that considerable amount of heavy components do not come out from the bed even at very low pressures in both dry and wet condition tests. Repeatability of the sorption/desorption processes - vital for possible commercial/industrial use - has been examined over various cycles. 相似文献
107.
现场总线控制系统浅谈 总被引:1,自引:0,他引:1
简述了现场总线控制系统的结构及其显优点。现场总线控制系统的结构包括:主控器、总线接口、电源、输入/输出接点、总线电揽和终端电阻。另外对其显优点做了逐一介绍。现场总线控制系统可在工业自动化控制系统中推广应用。 相似文献
108.
A new approach to study ergodicity of filtering processes is presented. It is based on the vanishing discount approach to discounted functional of filtering process. We show that limit superior of the Cesaro averages of the functionals is the same for all initial conditions from which the uniqueness of invariant measures of filtering processes follows. The approach is based on certain assumption for which we provide a sufficient condition using concavity arguments. In addition we show the existence of solutions to the Poisson equation corresponding to filtering process with concave functional. The assumptions are then extended to the controlled case and using similar concave arguments we obtain the existence of solutions to the Bellman equation corresponding to partially observed average cost per unit time problem. 相似文献
109.
设计一条钢筋网自动化焊接生产线,包括经料送料平台、纬料自动分料及上料机构、多点电阻点焊机、接料平台、卸料机械手。从上料到出料依靠电机、汽缸之间的协调工作来实现。并由单片机和PLC实现控制功能,上位机用MCGS组态软件在整个过程监视现场,采集工作状态及参数,起到监控作用。 相似文献
110.
D.E. Kvasov D. Menniti A. Pinnarelli Y.D. Sergeyev N. Sorrentino 《Electric Power Systems Research》2008
In this paper, the problem of global tuning of fuzzy power-system stabilizers (FPSSs) present in a multi-machine power system in order to damp the power system oscillations is considered. In particular, it is formulated as a problem of global minimization of a multiextremal black-box function over a multidimensional hyperinterval. A global optimization technique, recently proposed, is used for solving the stated problem: the search hyperinterval is partitioned into smaller hyperintervals and the objective function is evaluated only at two vertices corresponding to the main diagonal of the generated hyperintervals, thus avoiding unnecessary ponderous simulations. Then, the performances of this technique are numerically compared with ones of a genetic algorithm (GA). 相似文献