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Model-based diagnosis of incomplete discrete-event system with rough set theory

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Science China(Information Sciences) 2017年第1期60卷 190-200页

作者： Xuena GENG Dantong OUYANG yonggang zhang Key Laboratory of Symbolic Computation and Knowledge Engineering Ministry of EducationJilin University College of Computer Science and Technology Jilin University

Fault diagnosis of discrete-event system(DES) is important in the preventing of harmful events in the system. In an ideal situation, the system to be diagnosed is assumed to be complete; however, this assumption is rather restrictive. In this paper, a novel approach, which uses rough set theory as a knowledge extraction tool to deal with diagnosis problems of an incomplete model, is investigated. DESs are presented as information tables and decision tables. Based on the incomplete model and observations, an algorithm called Optimizing Incomplete Model is proposed in this paper in order to obtain the repaired model. Furthermore, a necessary and sufficient condition for a system to be diagnosable is given. In ensuring the diagnosability of a system, we also propose an algorithm to minimize the observable events and reduce the cost of sensor selection.

关键词： model-based diagnosis diagnosability discrete-event system finite state machine rough set theory

IN-SITU OBSERVATION OF CRACK PROPAGATION IN PST CRYSTALS OF Ti-49% AlALLOY

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中国有色金属学会会刊：英文版 1999年第1期9卷 65-71页

作者： Lu, Yonghao zhang, yonggang Chen, Changqi Beijing Univ of Aeronautics and Astronautics Beijing China

１ＩＮＴＲＯＤＵＣＴＩＯＮγＴｉＡｌｂａｓｅａｌｏｙｈａｓｂｅｅｎｏｆｍｕｃｈｉｎｔｅｒｅｓｔａｓｓｔｒｕｃｔｕｒａｌｍａｔｅｒｉａｌｓｆｏｒｅｌｅｖａｔｅｄｔｅｍｐｅｒａｔｕｒｅａｅｒｏｓｐａｃｅａｐｐｌｉｃａｔ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮγＴｉＡｌｂａｓｅａｌｏｙｈａｓｂｅｅｎｏｆｍｕｃｈｉｎｔｅｒｅｓｔａｓｓｔｒｕｃｔｕｒａｌｍａｔｅｒｉａｌｓｆｏｒｅｌｅｖａｔｅｄｔｅｍｐｅｒａｔｕｒｅａｅｒｏｓｐａｃｅａｐｐｌｉｃａｔｉｏｎｓｂｅｃａｕｓｅｏｆｉｔｓｌ...

关键词： PST crystal fracture behavior crack path toughness mechanism

南美桑托斯盆地深水区古拉绍-1井油气勘探发现及意义

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石油学报 2024年第2期45卷 339-347页

作者：何文渊黄先雄王红平汪望泉范国章丁梁波赵俊峰朱晓辉张勇刚庞旭李伟强左国平杨柳王朝锋中国石油国际勘探开发有限公司北京100034 中国石油杭州地质研究院浙江杭州310023

2021年,南美桑托斯盆地深水区风险探井古拉绍-1井获得重大原油发现,地层测试获得日产千吨高产油流,确定了巴西阿拉姆区块超大型油藏的勘探潜力,证实其具有规模商业开发前景。为了更好认识这一重大突破,在区域地质背景分析的基础上,结合... 详细信息

2021年,南美桑托斯盆地深水区风险探井古拉绍-1井获得重大原油发现,地层测试获得日产千吨高产油流,确定了巴西阿拉姆区块超大型油藏的勘探潜力,证实其具有规模商业开发前景。为了更好认识这一重大突破,在区域地质背景分析的基础上,结合油气勘探历程,对古拉绍-1井的构造-沉积背景、油气成藏条件以及油藏特点进行了详细分析。研究结果表明:①阿拉姆区块位于桑托斯盆地阿拉姆—乌拉普鲁(阿—乌)隆起带,与卢拉—苏格(卢—苏)隆起带的卢拉油田隔"湖"相望,具有相似的构造沉积背景;盆地中央大型古隆起为碳酸盐岩沉积提供了有利条件。②阿拉姆区块邻近主力生烃凹陷,油源充足。③继承性古隆起控制了湖相碳酸盐岩储层连片分布。④盐岩、盐上灰泥岩和泥岩对油藏形成了多重有效封盖。⑤盐下背斜圈闭规模大,为有利油气指向区。⑥古拉绍-1井油藏属于低CO_(2)、低H_(2)S中质油超压油藏。古拉绍-1井的成功钻探是巴西桑托斯盆地盐下核心区向外围区拓展取得的重大突破,是中国石油天然气集团有限公司(中国石油)坚持海外风险勘探的重大成功,是中国石油海外深水油气合作发展的又一成功实践,对巴西桑托斯盆地盐下油气勘探工作以及中国石油深水油气业务发展战略具有指导意义。

关键词：桑托斯盆地深水古拉绍-1井超大型油藏湖相碳酸盐岩

Novel Analytical Model of Mean Temperature and Experimental Research on the Rail Universal Rolling

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Chinese Journal of Mechanical Engineering 2009年第3期22卷 376-383页

作者： DONG yonggang zhang Wenzhi SONG Jianfeng College of Mechanical Engineering Yanshan University Qinhuangdao 066004 China

For building the analytical model of mean temperature in rail universal rolling, the cross-section of workpieces and the profile of horizontal roll and vertical roll are simplified rationally. The mean temperature of the web of rail, the top of rail and the base of rail are considered individually. The temperature rises for plastic deformation and friction incorresponding deformation zone, the temperature drop for contact is calculated on the base of variation principle and energy conservation law. Then the mean temperature is obtained. For verifying the theoretical model, the 18 kg/m light rail universal rolling experiments are accomplished in Yanshan University Rolling Laboratory, China and the surface temperature is measured. The surface temperature is not exact enough to express the true temperature and the mean temperature can show the status of the true temperature basically. So the mean temperature can be used to express the true temperature and this theoretical model and its results can be applied as an important reference to control the temperature of rail universal rolling and the heat treatment of the rolled rail.

关键词： mean temperature light rail universal mill rolling experiments surface temperature

基于lncRNA TUG1介导miR-320调控PTEN/Cosmc通路探讨肾炎止血丸治疗IgA肾病的作用机制

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中国中医药科技 2024年第3期31卷 391-396页

作者：陈瑶张永刚闫晓明王海艳李莲花张佩青陈明黑龙江省中医药科学院黑龙江哈尔滨150036 齐齐哈尔市第一医院黑龙江齐齐哈尔161005

目的:观察肾炎止血丸对IgA肾病(IgAN)模型大鼠的治疗作用及其对lncRNA TUG1介导miR-320-5p调控PTEN/Cosmc通路的影响。方法:采用“牛血清白蛋白+四氯化碳+脂多糖”联用法构建IgAN大鼠模型,32只大鼠随机分为正常对照组、模型组、氯沙坦... 详细信息

目的:观察肾炎止血丸对IgA肾病(IgAN)模型大鼠的治疗作用及其对lncRNA TUG1介导miR-320-5p调控PTEN/Cosmc通路的影响。方法:采用“牛血清白蛋白+四氯化碳+脂多糖”联用法构建IgAN大鼠模型,32只大鼠随机分为正常对照组、模型组、氯沙坦钾片组[20 mg/(kg·d)]、肾炎止血丸组[3.6 g/(kg·d)],每组8只,均连续给药6周。留取血液、肠黏膜及肾组织标本,分别应用ELISA法检测血清磷酸酶及张力蛋白同源基因(PTEN)、核心1β1,3半乳糖基转移酶伴侣蛋白(Cosmc)、半乳糖缺陷型IgA1(Gd-IgA1)水平;采用Real-time PCR、Western blot检测肠黏膜组织、肾脏组织lncRNA TUG1、miR-320、PTEN、Cosmc mRNA及蛋白表达。结果:①血清PTEN、Cosmc、Gd-IgA1:与模型组比较,各给药组PTEN、Cosmc升高明显(均P0.05)。各给药组肾组织Cosmc表达升高有极显著差异(P<0.01),与氯沙坦钾片组比较,肾炎止血丸肾组织PTEN升高有显著差异(P<0.05),Cosmc表达升高有极显著性差异(P<0.01)。结论:肾炎止血丸能够改善IgAN大鼠肾损伤;其作用机制可能与参与lncRNA TUG1介导miR-320调控PTEN/Cosmc通路有关。

关键词：肾炎止血丸 IgA肾病 lncRNA TUG1 miR-320 PTEN Cosmc 大鼠

Study on Distribution of Electrocatalytic Reaction Efficiency in a Three-Dimensional Electrocatalytic Reactor

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China Petroleum Processing & Petrochemical Technology 2021年第3期23卷 30-39页

作者： Lu Kaitian zhang yonggang School of Environmental Science and Engineering Tiangong University300387

In order to explore the effect of particle position on the electrocatalytic reaction rate at different positions in three-dimensional electrocatalytic reactor,using methylene blue as the simulated organic wastewater,and spherical graphite particles as the particle electrode,the potential distribution in three-dimensional electrocatalytic reactor was simulated by using COMSOL Multiphysics software.A multivariate logarithmic regression model of reaction kinetic constant and position was established by mathematical *** electrocatalytic reaction rates were predicted at different locations in the *** results show that the degradation ability of particle electrode to pollutants is uneven in the electrocatalytic *** increase of electric field intensity and particle size will improve the difference of reaction *** closer the particle electrode is to the anode,the stronger the pollutant degradation ability would *** reaction rate of the same particle electrode at different locations varies greatly,which can be roughly divided into three regions according to the degree of difference,among which the central region of the particle has the highest electrocatalytic reaction efficiency.

关键词： particle electrode COMSOL multiphysics electrocatalytic efficiency logarithmic regression model

An evaporation duct prediction model coupled with the MM5

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Acta Oceanologica Sinica 2015年第5期34卷 46-50页

作者： JIAO Lin zhang yonggang Department of Military Oceanography Dalian Naval Academy

Evaporation duct is an abnormal refractive phenomenon in the marine atmosphere boundary layer. It has been generally accepted that the evaporation duct prominently affects the performance of the electronic equipment over the sea because of its wide distribution and frequent occurrence. It has become a research focus of the navies all over the world. At present, the diagnostic models of the evaporation duct are all based on the Monin-Obukhov similarity theory, with only differences in the flux and character scale calculations in the surface layer. These models are applicable to the stationary and uniform open sea areas without considering the alongshore effect. This paper introduces the nonlinear factor a and the gust wind item wg into the Babin model, and thus extends the evaporation duct diagnostic model to the offshore area under extremely low wind speed. In addition, an evaporation duct prediction model is designed and coupled with the fifth generation mesoscale model （MMS）. The tower observational data and radar data at the Pingtan island of Fujian Province on May 25-26, 2002 were used to validate the forecast results. The outputs of the prediction model agree with the observations from 0 to 48 h. The relative error of the predicted evaporation duct height is 19.3% and the prediction results are consistent with the radar detection.

关键词： evaporation duct diagnosis mesoscale model (MM5) evaporation duct prediction model numerical simulation

PAN/PI基多孔碳纤维的制备及其CO_(2)吸附性能研究

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合成纤维工业 2024年第2期47卷 13-18页

作者：蔡晨阳闫圣国李瑞劼张永刚王雪飞浙江工业大学浙江杭州310014 中国科学院宁波材料技术与工程研究所浙江宁波315201

在聚丙烯腈(PAN)/二甲基亚砜溶液中加入联苯四甲酸二酐和二氨基二苯醚合成PAN/聚酰胺酸(PAA)共混纺丝原液,然后通过湿法纺丝、在空气气氛中预氧化/亚胺化、在氮气(N_(2))气氛下碳化制得“莲藕状”截面的PAN/聚酰亚胺(PI)基多孔碳纤维,... 详细信息

在聚丙烯腈(PAN)/二甲基亚砜溶液中加入联苯四甲酸二酐和二氨基二苯醚合成PAN/聚酰胺酸(PAA)共混纺丝原液,然后通过湿法纺丝、在空气气氛中预氧化/亚胺化、在氮气(N_(2))气氛下碳化制得“莲藕状”截面的PAN/聚酰亚胺(PI)基多孔碳纤维,研究了不同PI含量PAN/PI基多孔碳纤维的表观形貌、化学结构及元素组成,并评估了模拟烟道环境中多孔碳纤维的二氧化碳(CO_(2))吸附性能。结果表明:随PI含量的增加,纤维内部的孔隙变得更大、更密集,形成类似“莲藕状”的截面结构,吡咯/吡啶酮氮含量也随PI含量的增加而有规律的增加,当PI质量分数为30%时,PAN/PI基多孔碳纤维N结构形式中吡咯/吡啶酮氮的占比高达70.46%;在40℃、CO_(2)体积分数为15%、N_(2)体积分数为85%的模拟烟道环境中,PI质量分数为30%的PAN/PI基多孔碳纤维的CO_(2)吸附量相对最高,达0.66 mmol/g,且能更加快速地达到吸附平衡,具有优异的CO_(2)吸附性能。

关键词：聚丙烯腈聚酰胺亚胺多孔碳纤维湿法纺丝二氧化碳吸附性能氮含量

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多元料浆气化炉烧嘴法兰缝隙超温原因分析及对策

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大氮肥 2024年第2期47卷 77-80页

作者：李伟张永刚曹新安李水龙雷浩王建霞华亭华煤清能煤化工有限责任公司甘肃华亭744100

针对多元料浆气化炉投料初期出现工艺烧嘴法兰超温问题,通过流场模拟分析、工艺烧嘴装配尺寸调整、炉口物理填充、中心氧量调整、负荷调整等思路,提出相应解决措施。

关键词：多元料浆气化炉工艺烧嘴法兰超温