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《等离子体科学和技术》2019,21(11):115403-44
In this paper, a honeycomb structure jet array with seven jet units was adopted to generate plasmas. Both the average discharge power and the emission intensity of the main excited species increase with increasing applied voltage. There are three stages of discharge evolution at different applied voltages: initial discharge, uniform discharge and strong coupling discharge.The spatial distribution of the emission intensity of the excited species can be divided into three categories: growth class, weakening class and variation class. The gas temperature along the whole plasma plume at different applied voltages is maintained at around 320K and can be widely used in heat-labile applications.  相似文献   
53.
The ordered weighted averaging (OWA) operators play a crucial role in aggregating multiple criteria evaluations into an overall assessment supporting the decision makers’ choice. One key point steps is to determine the associated weights. In this paper, we first briefly review some main methods for determining the weights by using distribution functions. Then we propose a new approach for determining OWA weights by using the regular increasing monotone quantifier. Motivated by the idea of normal distribution-based method to determine the OWA weights, we develop a method based on elliptical distributions for determining the OWA weights, and some of its desirable properties have been investigated.  相似文献   
54.
辽河滩海地区海月构造带东三段沉积期,三角洲前缘砂体受湖岸流和波浪的改造,形成了一系列滩坝砂沉积,细分为滩砂和坝砂,水动力强则形成坝砂,水动力弱则形成滩砂;滩坝砂平行于湖岸线呈带状分布,易于形成岩性圈闭。滩坝砂受砂体发育规模、储层物性、断裂输导体系及封堵性等多种因素控制,在滩坝砂较为发育的东三下段,靠近海南断层、盖州滩断层且封堵条件优越的滩坝砂最易于成藏。  相似文献   
55.
Power loss reduction has an important role in operating electric distribution network system. There are a lot of methods for reduction power loss such as capacitor placement, distributed generation placement and electric distribution network reconfiguration (EDNR). Among these methods, the EDNR is an efficient technique to reduce power loss due to without taking any costs. However, the EDNR problem is a nonlinear, discrete problem and lots of extreme points. Therefore, it is necessary to have efficient methods for solving the EDNR problem. In this paper, an improved cuckoo search algorithm (ICSA) is proposed for solving the EDNR problem. In which, based on disadvantages of exploration and exploitation process of cuckoo search algorithm (CSA) for solving the EDNR problem, a local search mechanism is added to exploit candidate solutions existing around the current best solution. The calculated results on the simple distribution networks to complex distribution networks show that ICSA has ability for finding the global optimal solution with much smaller iterations and better quality of obtained solution compared with CSA and some other improved versions of CSA. The performance comparisons with other existing methods available in previous studies and the software of Power System Simulator/Advanced Distribution Engineering Productivity Tool (PSS/ADEPT) also lead to the better electric distribution network configuration with smaller total power losses. As a result, ICSA is a potential and reliable method for solving the EDNR problems.  相似文献   
56.
The particles with a narrow size distribution are proper products in a fluid bed granulation and coating. As well, the process efficiency is one of the most important parameters, and the wall deposition of sprayed liquid reduces it. The modality of spray volume distribution is a key parameter in the definition of particle size distribution and process efficiency. This work is done in two steps: In the first step, an experimental study on spray characteristics including spray flux distribution, spray cone angle, and discharge coefficient is conducted. Based on the experimental data, the curves of liquid volume flux versus nozzle pressure and height are obtained. The results indicate that the flux distribution changes significantly with even small pressure and height changes. In the second step, the granulation process is carried out in a semi-industrial conical fluid bed, and the particles size distribution curves and the deposited mass on the bed wall are obtained. The results show that the precise determination of the spray flux distribution is an appropriate way to predict the well-advised nozzle pressure/height in order to achieve the narrow particle size distribution and high efficiency of the process.  相似文献   
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Ab initio molecular-dynamics simulations have been used to investigate the liquid and amorphous Al94-xNi6Lax (x=3-9) alloys. Through calculating the pair distribution functions and partial coordination numbers, the structure and properties of these alloys are researched, which will help the design bulk metallic glass. The concentration of La atoms can affect the short-range order of Al94-xNi6Lax alloys, which is also studied in this calculation result.  相似文献   
59.
In the present paper, an unknown input multiobserver (UIMO) is designed for the state estimation of uncertain non-linear systems. A discrete decoupled state multimodel is exploited to describe the behavior of non-linear systems. A particular transformation of uncertainties to unknown inputs is considered. The LMI approach is used to establish the convergence conditions of the state estimation error. The efficiency of the proposed strategy is emphasized through an illustrative example and a real time application on a semi-batch reactor that lead to good performance in terms of robustness, convergence speed and precision.  相似文献   
60.
针对高可靠度机载多余度EWIS各组成部分寿命服从指数分布但参数未知的情况,提出采用无失效数据可靠度分析方法评估EWIS的可靠度水平。通过Monte-Carlo仿真方法对连接形式为“先并联、后串联”EWIS各组成部分寿命进行抽样,利用“最小最大值”方法获得系统寿命的抽样值,用概率纸检验法初步判断EWIS寿命是否服从威布尔分布,再用Pearson拟合优度检验法判断EWIS寿命是否服从威布尔分布。结合无故障飞行时间的样本值与EWIS寿命服从威布尔分布的假设,采用无失效数据分析方法评估EWIS的可靠度水平。研究方法对机载多余度EWIS无失效数据可靠度分析有一定的贡献。  相似文献   
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