基于UML的学生食堂自动收费系统研究

简要介绍了统一建模语言UML(UnifiedModelingLanguage),给出了学生食堂自动收费系统问题描述,根据问题描述对该系统建立了类模型,用例模型,活动图和顺序图,这些图为此系统的形成奠定了基础。     

Supervisory control of timed discrete event systems under partial observation based on activity models and eligible time bounds

To avoid the state–space explosion by including tick events in timed discrete event systems (DESs) under partial observation, a notion of eligible time bounds is introduced and based on the notion, controllability and observability conditions of languages are presented. In particular, this paper shows that these controllability and observability conditions are necessary and sufficient for the existence of a supervisor to achieve the given language specification.     

发电厂全面经济活动分析系统

该系统通过建立通用指标分析模型 ,将采集过来的生产数据、财务数据等进行分类、计算加工后逐个自动求得各因素变化对综合经济指标变化的影响方向和影响幅度。     

活性二氧化锰的研制与分析

本文对制备活性二氧化锰的工艺条件进行了探索,并使用DTA、X-衍射等方法分析讨论了不同制备工艺对AMD结构的影响。     

锰铁合金熔体中碳和磷的热力学

通过实验测定１６７３Ｋ时碳的溶解度，得到Ｍｎ－Ｆｃ－Ｃ系和Ｍｎ－Ｐ－Ｃ系碳的溶解度公式为：Ｎｃ＝０．２７０－０．０５６７×ＮＦｅ和Ｎｃ＝０．２７０－１．２９１１×Ｎｐ．用这些公式计算出１６７３Ｋ时一些活度的相互作用系数，例如：等等。同时也计算出１６７３Ｋ时的ｌｎ和△的值．     

扑虱螟乳油活性成分的气相色谱分析

在恒温条件下，在同一色谱柱上分析乳油中甲胺磷、甲基－１６０５、异稻瘟净和噻嗪酮的含量，并对其重现性、线性范围及回收率进行了测定。结果表明：变异系数为１．２０～２．０１，相关系数为０．９９５２～０．９９８５，平均回收率为９６．０６％～１０１．０７％。     

影响MH电极电催化活性的因素

本文综述并分析了MH电极贮氢电极过程及影响电极贮氢反应速度的因素,总结了各种提高MH电极电催化活性的方法,其中包括微包覆,双相合金等一系列材料和电极处理途径。     

Finitely concentrated partial molar excess properties of solvent/polymer [poly(4-methylstyrene) (PMS), poly(vinylbenzyl chloride) (PVBC)] systems

The finitely concentrated activity coefficients and partial molar excess properties of solvents were measured with inverse gas chromatography (IGC) in polymer solutions containing a poly(4-methylstyrene) (PMS) or a poly(vinylbenzyl chloride) (PVBC). The experimental temperature ranges were 373.15 K to 413.15 K for PMS and 353.15 K to 393.15 K for PVBC. They were over melting point or glass transition temperature of each polymer. Ten kinds of solvents (Acetone, n-Heptane, Cyclohexane, Chloroform, Methylisobutylketone, Trichlorobenzene, Benzene, Toluene, Ethylbenzene, Chlorobenzene) that are important in the chemical engineering field were arbitrarily chosen for binary polymer solutions. The external degree of freedom of original UNIFAC-FV model was empirically modified to give flexibility to itself as a C₁=A+BT from the experimental data in finite concentration. The UNIFAC-FV model included a new external degree of freedom as a function of temperature. The parameters (A, B) were estimated by correlating the activities of solvent with the modified model and extended to predict the partial molar excess properties of solvents in the finite-concentrated polymer solutions. The predicted values were compared with them by original UNIFAC-FV as well as the experimental data. The results obtained with the revised model using the new parameter showed the higher quality than the results obtained by original model.     

氧化亚铁硫杆菌亚铁氧化活性诱变育种理论探讨

结合已有的实验研究探讨了氧化亚铁硫杆菌亚铁氧化活性诱变育种过程中出现的几个理论问题 :突变基因性质 ;正突变与细菌修复系统 ;诱变剂选择与“钝化”防止 ;遗传稳定性与抑制基因突变 ;有效的育种程序。以期在进一步诱变育种中加快进程 ,获得遗传稳定、氧化快的突变株     

一种基于特征选取的传感器选择方法

基于传感器的行为识别是环境智能中的一个关键问题,但是"该使用哪些种类的传感器?"以及"每种传感器该使用多少个?"都还是有待解决且具有挑选性的问题。针对这些问题,提出一种基于特征选取的方法来选择传感器。实验结果显示,在OPPORTUNITY标准数据集上,1)相比于加速度传感器和陀螺仪传感器,磁性传感器的识别效果较好;2)只使用被选取的5个最好的磁性传感器特征也能达到和使用全部传感器特征类似的识别准确度。