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1.
腾小羽 《电网技术》1996,20(5):26-30
本介绍一种新的基于开放系统环境的计算机监控系统软件的开发研究及其设计目标、实现方法及应用情况。  相似文献   
2.
用相干态的方法得到旋转磁场中自旋为j的粒子的态矢量的严格表达式,由此可计算相干态和叠加相干态的Abaronov-Anandan相位(AA相让).并具有清楚的物理图象.  相似文献   
3.
采用MOCVD实现了AlGaAs/GaAs量子阱结构,获得了连续输出20W激光二极管线列阵,线列阵长度1.0cm,激射波长808±4nm。  相似文献   
4.
户式中央空调发展方向的探讨   总被引:2,自引:1,他引:1  
本文描述了我国户式中央空调的发展现状,分析了三种户式中央空调各自的特点,提出了把风管式机组作为我国户式中央空调的发展方向。  相似文献   
5.
Polyoxymethylene (POM) composites filled with low-density polyethylene (LDPE) and rice husk flour (RHF) were prepared by injection molding. The POM/5 wt % LDPE/7.5 wt % RHF composite exhibited the lowest wear rate, whereas the coefficient of friction remained low, and the POM/5 wt % LDPE/5 wt % RHF composite had the best mechanical properties. X-ray diffraction analysis was carried out, and the worn surfaces were examined with scanning electron microscopy. The results showed that the addition of the filler reduced the crystallinity degree of the POM composites. The main wear mechanism for unfilled POM was adhesion, whereas for the POM composites, wear seemed to occur mainly by fatigue and abrasion. It was experimentally confirmed that the POM composite filled with LDPE and RHF, which is well-performing, low-cost, and environmentally friendly, could be a potential material for tribological applications. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
6.
Although lipases are widely applied in a wide variety of reactions, available information on the factors that are responsible for the substrate specificities of lipases from different sources is scarce. In this paper, nine lipase‐producing microorganism strains were isolated from oil‐containing samples. The properties of these enzymes, including pH optima, temperature optima, thermal stability, and pH stability, vary significantly with the different sources from which these lipases were isolated. The substrate specificities of the nine lipases, including fatty acid and positional specificities, were also studied. The fatty acid specificities of the nine lipases were observably different toward 15 substrates with different carbon chain lengths, different saturation degrees and different side chains. The lipases from S3 Penicillium citrinum (PCL), MJ1 Aspergillus niger (ANL), MJ2 Aspergillus oryzae (AOL), YM Bacillus coughing (BCL), S9 Geotrichum candidum (GCL), and S11 Candida lypolytica (CLL) showed the strongest specificities to short‐chain esters, and the other lipases showed strong selectivity for medium‐ or long‐chain and branched esters. The positional specificities were examined by analyzing the hydrolytic products of triolein catalyzed by the nine lipases, using TLC. The lipases can be mainly classified into two groups by their specificities for the ester bond at position 2 of triglycerides; one group can selectively hydrolyze the ester bond at position 2 of the triglycerides, the other group cannot. All these nine lipases were divided into four groups by hierarchical clustering analysis on the basis of the results of fatty acid and positional specificities.  相似文献   
7.
液相对流对固液界面稳定性的影响   总被引:1,自引:0,他引:1  
以模型合金丁二腈-乙醇的强制性晶体生长为基础,利用自行研制的液相对流驱动装置,详细考查了液相自然对流及强迫对流作用下,模型合金平界面失稳的动态生长过程,证实了液相的流动加快了液相温度与浓度分布的均匀化,从而增强了液/固界面的稳定性。并且随流动速度的增加,界面稳定性提高。  相似文献   
8.
叶片数是影响超低比转速斜流式水轮机水力性能的因素之一。文章利用Fluent 16.0软件,研究分析了不同叶片数模型在不同流量工况下,外特性曲线以及内部流场分布图。结果表明:不同叶片数时,流量从最高效率点向小流量变化时效率下降的速度要比从最高效率点向大流量变化时的快。对于具体参数组合的超低比转速斜流式水轮机,存在最优的叶片数使得其水力性能最优。  相似文献   
9.
Wang  Nan  Zou  Qi  Ma  Qiulin  Huang  Yaping  Lou  Haitao  Wu  Xiaoyu  Liu  Huiyong 《Applied Intelligence》2021,51(11):8010-8029

We propose a novel online multiple object tracker taking structure information into account. State-of-the-art multi-object tracking (MOT) approaches commonly focus on discriminative appearance features, while neglect in different levels structure information and the core of data association. Addressing this, we design a new tracker fully exploiting structure information and encoding such information into the cost function of the graph matching model. Firstly, a new measurement is proposed to compare the structure similarity of two graphs whose nodes are equal. With this measurement, we define a complete matching which performs association in high efficiency. Secondly, for incomplete matching scenarios, a structure keeper net (SKnet) is designed to adaptively establish the graph for matching. Finally, we conduct extensive experiments on benchmarks including MOT2015 and MOT17. The results demonstrate the competitiveness and practicability of our tracker.

  相似文献   
10.
石墨化率不同的自焙炭块的热膨胀   总被引:1,自引:0,他引:1  
采用精密垂直拉杆膨胀仪在14~1000℃范围内测量了具有不同石墨化率的自焙炭块的相对热伸长量,并由此获得了热线膨胀系数α。结果表明:石墨化率一定时,α值在较低温度下随温度升高而增加,在较高温度下,α值随温度变化不明显;恒温时,石墨化率越高,α值越低。讨论了单位热应力下的弹性模量概念  相似文献   
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