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e-control技术及其在多媒体教学环境中的应用
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作者 钟晓流 《实验技术与管理》 CAS 北大核心 2009年第3期7-10,17,共5页
e-control技术及其应用系统是多媒体应用环境智能化集中控制系统发展到互联网通讯阶段的产物,在多媒体教学环境与视听环境中具有重要意义和广泛的应用前景。e-control系统是一个智能化集中控制系统的集成概念。该文以e-control技术在清... e-control技术及其应用系统是多媒体应用环境智能化集中控制系统发展到互联网通讯阶段的产物,在多媒体教学环境与视听环境中具有重要意义和广泛的应用前景。e-control系统是一个智能化集中控制系统的集成概念。该文以e-control技术在清华大学教学环境中的应用为实例,介绍了e-control技术及其应用系统的基本架构、工作原理、技术特点和系统功能,对相关应用领域或类似工程案例具有良好的借鉴或参考意义。 展开更多
关键词 e-control技术 e-control系统 教学环境
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Cause of over Water Quality Standard and Control Measures of State-controlled Sections in Northern Water-deficient Area of Jiangsu 被引量:5
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作者 胡永定 韩宝平 +1 位作者 钱新 袁兴程 《Meteorological and Environmental Research》 CAS 2010年第2期91-94,99,共5页
Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan r... Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology. 展开更多
关键词 State-controlled sections Cause analysis Control measures Water-deficient area China
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A machine learning approach to quality-control Argo temperature data
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作者 Qi Zhang Chenyan Qian Changming Dong 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第4期1-7,共7页
本文提出了一种基于机器学习的Argo浮标温度异常值检测方法.该方法采用机器学习无监督算法高斯混合模型对Argo浮标数据进行聚类分析,并构建包围所有数据点的最小多边形的凸包.基于射线投影算法实现点在多边形内分析,通过自动识别数据点... 本文提出了一种基于机器学习的Argo浮标温度异常值检测方法.该方法采用机器学习无监督算法高斯混合模型对Argo浮标数据进行聚类分析,并构建包围所有数据点的最小多边形的凸包.基于射线投影算法实现点在多边形内分析,通过自动识别数据点位于凸包内外来判断该数据点数据质量的好坏.本文采用南海区域Argo浮标数据对该方法进行测试,结果表明该方法可以识别70%以上的包含异常值的温度剖面,同时自动标记出各异常值点. 展开更多
关键词 质量控制 机器学习 异常值检测 高斯混合模型 凸包 点在多边形内
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基于Block-Controlled网格划分法的儿童胸部建模及验证 被引量:3
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作者 曹立波 蒋彬辉 +1 位作者 冒浩杰 杨金海 《汽车工程》 EI CSCD 北大核心 2014年第3期298-303,共6页
针对目前缺乏合适的儿童胸部有限元模型,基于临床治疗过程中获得的儿童CT和MRI数据,采用Block-Controlled网格划分法建立了具有详细解剖结构的10岁儿童胸部有限元模型。模型的材料参数由成人胸部材料参数比例缩放获得。利用心肺复苏急... 针对目前缺乏合适的儿童胸部有限元模型,基于临床治疗过程中获得的儿童CT和MRI数据,采用Block-Controlled网格划分法建立了具有详细解剖结构的10岁儿童胸部有限元模型。模型的材料参数由成人胸部材料参数比例缩放获得。利用心肺复苏急救中获得的儿童胸部响应数据对模型进行验证。结果表明该模型能较好地预测10岁儿童的胸部响应刚度,具有良好的生物逼真度,可用于低速碰撞下的儿童损伤机理和损伤防护的研究。 展开更多
关键词 儿童损伤 Block-controlled网格划分 有限元模型 验证
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Model-View-Controller设计模式实例研究 被引量:12
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作者 李赤林 王琳 《计算机与现代化》 2003年第3期12-14,18,共3页
从MVC的起源谈起,以一个十分简单的Java例子来说明MVC的设计方式,最后以图解的方式揭示了MVC在实际运用中所采用的具体做法。
关键词 MODEL-VIEW-controlLER 实例 软件设计模式 面向对象 图形界面
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Sustainable Ecosystem Management via H-Control Theory of Stochastic Systems
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作者 Michael Park 《Journal of Geoscience and Environment Protection》 2023年第2期1-12,共12页
In this paper, aiming to provide accurate protocols for management of sustainable ecosystems, a design methodology of H<sub>&#8734;</sub>-controller for hunter-prey model under exposure to exogenous di... In this paper, aiming to provide accurate protocols for management of sustainable ecosystems, a design methodology of H<sub>&#8734;</sub>-controller for hunter-prey model under exposure to exogenous disturbance and stochastic noise is presented. Along the development, solution procedure of the stochastic Hamilton-Jacobi-Isaacs equation via Successive Galerkin’s Approximation is described. Utilizing the proposed solution methodology of Hamilton-Jacobi-Isaacs equation, H<sub>&#8734;</sub>-controller of hunter-prey model was successfully designed. Robustness and performance against exogenous disturbance of the designed H<sub>&#8734;</sub>-controller is validated and confirmed by numerical simulations including Monte-Carlo simulation by Simulink software on MATLAB. 展开更多
关键词 Galerkin Method Feedback Design of Ecosystems Hamilton-Jacobi Equation Predator-Prey Model Sustainable Ecosystem Nonlinear Control
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基于case-control法分析鸡脂肪性状QTL区域SNP与性状的关系
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作者 唐军 王思兵 +2 位作者 罗成龙 聂庆华 张细权 《广东农业科学》 CAS CSCD 北大核心 2012年第8期117-120,共4页
以华南农业大学杏花鸡×隐性白羽洛克鸡全同胞家系为群体,选取腹脂重性状两尾样本共96个个体,在已报道家禽腹脂重性状QTL区域相关基因中选取14个SNP,采取PCR-RFLP法进行基因定型、case-control法进行关联分析,经100000次重排检验后... 以华南农业大学杏花鸡×隐性白羽洛克鸡全同胞家系为群体,选取腹脂重性状两尾样本共96个个体,在已报道家禽腹脂重性状QTL区域相关基因中选取14个SNP,采取PCR-RFLP法进行基因定型、case-control法进行关联分析,经100000次重排检验后,发现rs16480367、rs15687533、rs16481126、rs15685408均达到显著水平,P值分别为0.0202、0.0215、0.0257、0.0319。说明这4个SNP位点与脂肪性状有一定的相关性,可为家禽的标记辅助选择提供理论参考。 展开更多
关键词 脂肪性状 SNP CASE-control
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Dynamic Modelling and Design of a Servomechanism for Hydraulic Directional-Control Valves 被引量:1
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作者 Tan Runbua and A. J. Reynolds 《河北工业大学学报》 CAS 1997年第A01期58-75,共18页
This paper analyses a control strategy applicable in heaVy-duty hydraulic Systems,namely, the introduction of a servovalve to achieve smoother operation of direCtional-control valves that serve also as flow-control va... This paper analyses a control strategy applicable in heaVy-duty hydraulic Systems,namely, the introduction of a servovalve to achieve smoother operation of direCtional-control valves that serve also as flow-control valves over two fanges of operating conditions. A mathematical model of the dynamics of the System is etallished and design criteria are obtained from a linearised form of that model. The influence of variations in tile axial force on the spool of the main valve is investigated, and the use of the resultS in the design of systems of the proposed kind is discussed. 展开更多
关键词 HYDRAULIC System DYNAMIC Performance Servomechnaism FLOW-control VALVE Directional-control Valve.
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基于Require.js+koa2+Typescript+Routing-controllers框架设计与实现
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作者 毕好昌 徐在文 《集宁师范学院学报》 2022年第5期82-86,共5页
本框架设计采用Require.js实现JS文件的模块化和异步加载。以koa2作为后端API接口框架的核心底层引擎。通过typescript强类型提高开发效率,提升框架的稳定性和健壮性。通过routing-controllers装饰器设计,降低代码的冗余量,提高代码的... 本框架设计采用Require.js实现JS文件的模块化和异步加载。以koa2作为后端API接口框架的核心底层引擎。通过typescript强类型提高开发效率,提升框架的稳定性和健壮性。通过routing-controllers装饰器设计,降低代码的冗余量,提高代码的可维护性和可读性。从而为全栈工程师提供一个开箱即用的开源框架,同时也为学习者提供一定的理论依据。 展开更多
关键词 Require.js koa2 Typescript Routing-controllers 开源框架
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K-controllability and Approximate K-controllability of Nonlinear Neutral Systems in Banach Spaces
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作者 LU YUE CAI HUA LIU MING-JI 《Communications in Mathematical Research》 CSCD 2011年第3期207-214,共8页
In this paper, K-controllability and approximate K-controllability of non- linear neutral differential equations in Banach spaces are studied. Sufficient conditions are established for each of these types of controlla... In this paper, K-controllability and approximate K-controllability of non- linear neutral differential equations in Banach spaces are studied. Sufficient conditions are established for each of these types of controllability. The results are obtained by using Leray-Schauder theory. 展开更多
关键词 K-controllability approximate K-controllability m-accretive operator Mild solution preassigned response
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Multicenter case-control study of the risk factors for ulcerative colitis in China 被引量:25
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作者 Yu-Fang Wang Qin Ou-yang +16 位作者 Bing Xia Li-Na Liu Fang Gu Kai-Fang Zhou Qiao Mei Rui-Hua Shi Zhi-Hua Ran Xiao-Di Wang Pin-Jin Hu Kai-Chun Wu Xin-Guang Liu Ying-Lei Miao Ying Han Xiao-Ping Wu Guo-Bing He Jie Zhong Guan-Jian Liu 《World Journal of Gastroenterology》 SCIE CAS 2013年第11期1827-1833,共7页
AIM:To evaluate potential risk factors in the development of ulcerative colitis(UC) in China.METHODS:A total of 1308 patients with UC and 1308 age-matched and sex-matched controls were prospectively studied in China.T... AIM:To evaluate potential risk factors in the development of ulcerative colitis(UC) in China.METHODS:A total of 1308 patients with UC and 1308 age-matched and sex-matched controls were prospectively studied in China.The UC cases were collected from 17 hospitals in China from April 2007 to April 2010.Uniform questionnaires were designed to investigate risk factors including smoking,appendectomy,stress,socio-economic conditions,nonsteroidal antiinflammatory drugs(NSAIDs),oral contraceptives,diet,breastfeeding,infections and family sanitary conditions.Group comparisons by each factor were done using simple logistic regression analysis.Conditional logistic regression was used for multivariate analysis.RESULTS:By univariate analysis,the variables predictive of UC included feeling stress,light and heavy alcoholic drinking,spicy food,sugar consumption and infectious diarrhea,while heavy tea intake and tap water consumption were protective against UC.On multivariate analysis,the protective factor for UC was tap water consumption [odds ratios(OR) = 0.424,95%CI:0.302-0.594,P < 0.001];while the potential risk factors for UC were heavy sugar consumption(OR = 1.632,95%CI:1.156-2.305,P < 0.001),spicy food(light intake:OR = 3.329,95%CI:2.282-4.857,P < 0.001;heavy intake:OR = 3.979,95%CI:2.700-5.863,P < 0.001),and often feeling stress(OR = 1.981,95%CI:1.447-2.711,P < 0.001).Other factors,such as smoking habit,appendectomy,breastfeeding,a history of measles,rural or urban residence,education,oral contraceptives,and NSAID use have not been found to have a significant association with the development of UC in the present study.CONCLUSION:Our study showed tap water consumption was a protective factor for UC,while spicy food,heavy sugar consumption and often feeling stress were risk factors for UC in this Chinese population. 展开更多
关键词 ULCERATIVE COLITIS Risk factors CASE-control study
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The Principle of Mathematical Induction Applied to the Generalized Model for the Economic Design of X-Control Charts 被引量:1
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作者 Mohamed E. Seliaman Salih O. Duffuaa 《Open Journal of Applied Sciences》 2012年第4期236-240,共5页
Rahim and Banerjee [1] developed a general model for the optimal design of x-control charts. The model minimizes the expected cost per unit time. The heart of the model is a theorem that derives the expected total cos... Rahim and Banerjee [1] developed a general model for the optimal design of x-control charts. The model minimizes the expected cost per unit time. The heart of the model is a theorem that derives the expected total cost and the expected cycle length. In this paper an alternative simple proof for the theorem is provided based on mathematical induction. 展开更多
关键词 Discrete MATHEMATICS MATHEMATICAL INDUCTION Statistical Quality CONTROL Design of -control Charts HAZARD Rate Function
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Risk factors of intrahepatic cholangiocarcinoma in patients with hepatolithiasis:a case-control study 被引量:25
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作者 Zhen-Yu Liu,Yan-Ming Zhou,Le-Hua Shi and Zheng-Feng YinAuthor Affiliations:Molecular Oncology Laboratory and Department of Comprehensive Treatment I,Eastern Hepatobiliary Surgery Hospital,Second Military Medical University,Shanghai 200438,China Department of Hepato-Biliary-Pancreato-Vascular Surgery,First Affiliated Hospital,Xiamen University,Xiamen 361003,China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2011年第6期626-631,共6页
BACKGROUND:Why 3.3% to 10% of all patients with hepatolithiasis develop intrahepatic cholangiocarcinoma (ICC) remains unknown.We carried out a hospital-based case-control study to identify risk factors for the develop... BACKGROUND:Why 3.3% to 10% of all patients with hepatolithiasis develop intrahepatic cholangiocarcinoma (ICC) remains unknown.We carried out a hospital-based case-control study to identify risk factors for the development of ICC in patients with hepatolithiasis in China.METHODS:Eighty-seven patients with pathologically diagnosed hepatolithiasis associated with ICC and 228 with hepatolithiasis alone matched by sex,age (±2 years),hospital admittance and place of residence were interviewed during the period of 2000-2008.Odds ratios (OR) and 95% confidence intervals (CI) were calculated for each risk factor.RESULTS:Among the patients with hepatolithiasis associated with ICC,the mean age was 57.7 years and 61.0% were female Univariate analysis showed that the significant risk factors for ICC development in hepatolithiasis were smoking,family history of cancer,appendectomy during childhood (under age 20),and duration of symptoms >10 years.In multivariate stepwise logistic regression analysis,smoking (OR=1.931,95% CI:1.000-3.731),family history of cancer (OR=5.175,95% CI:1.216-22.022),and duration of symptoms >10 years (OR=2.348 95% CI:1.394-3.952) were independent factors.CONCLUSION:Smoking,family history of cancer and duration of symptoms >10 years may be risk factors for ICC in patients with hepatolithiasis. 展开更多
关键词 risk factors intrahepatic cholangiocarcinoma HEPATOLITHIASIS case-control study
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Glutathione S-transferases M1,T1 genotypes and the risk of gastric cancer:A case-control study 被引量:22
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作者 Lin Cai Shun-Zhang Yu Zuo-Feng Zhang Department of Epidemiology.Fujian Medical University,Fuzhou 350004,Fujian Province,ChinaDepartment of Epidemiology,Shanghai Medical University,Shanghai 200032,China Department of Epidemiology,UCLA School of Public Health,Los Angeles California,USA 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第4期506-509,共4页
AIM: Glutathione S-transferases (GSTs) are involved in the detoxification of many potential carcinogens and appear to play a critical role in the protection from the effects of carcinogens. The contribution of glutath... AIM: Glutathione S-transferases (GSTs) are involved in the detoxification of many potential carcinogens and appear to play a critical role in the protection from the effects of carcinogens. The contribution of glutathione S-transferases M1 and T1 genotypes to susceptibility to the risk of gastric cancer and their interaction with cigarette smoking are still unclear. The aim of this study was to determine whether there was any relationship between genetic polymorphisms of GSTT1 and GSTT1 and gastric cancer. METHODS: A population based case-control study was carried out in a high-risk area, Changle County, Fujian Province, China. The epidemiological data were collected by a standard questionnaire and blood samples were obtained from 95 incidence gastric cancer cases and 94 healthy controls. A polymerase chain reaction method was used to detect the presence or absence of the GSTT1 and GSTT1 genes in genomic DNA. Logistic regression model was employed in the data analysis. RESULTS: An increase in risk for gastric cancer was found among carriers of GSTT1 null genotype. The adjusted odds ratio (OR) was 2.63 95% Confidence Interval (95% CI) 1.17-5.88, after controlling for age, gender, cigarette smoking, alcohol drinking, and fish sauce intake. The frequency of GSTT1 null genotype in cancer cases (43.16%) was not significantly different from that in controls (50.00%). However, the risk for gastric cancer in those with GSTT1 null and GSTT1 non-null genotype was significantly higher than in those with both GSTT1 and GSTT1 non-null genotype (OR = 2.77, 95% CI 1.15-6.77). Compared with those subjects who never smoked and had normal GSTT1 genotype, ORs were 1.60 (95% CI:0.62-4.19) for never smokers with GSTT1 null type, 2.33 (95% CI 0.88-6.28) for smokers with normal GSTT1, and 8.06 (95% CI 2.83-23.67) for smokers with GSTT1 null type. CONCLUSIONS: GSTT1 gene polymorphisms may be associated with genetic susceptibility of stomach cancer and may modulate tobacco-related carcinogenesis of gastric cancer. 展开更多
关键词 Adult Aged Case-control Studies Female Genetic Predisposition to Disease GENOTYPE Glutathione Transferase Humans Male Middle Aged Polymorphism Genetic Research Support Non-U.S. Gov't Risk Factors SMOKING Stomach Neoplasms
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模糊控制技术在多工位输送机中的应用——基于Fuzzy-Control软件 被引量:2
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作者 路欣 《农机化研究》 北大核心 2010年第10期164-166,173,共4页
多工位输送机是一种可用在农药和化肥等农资产品纸塑包装后的装箱设备,其工作位置的定位要求快速准确,采用传统步进电机的开环控制难以达到要求。为此,以S7-300型PLC为平台,采用Fuzzy-Control软件运用模糊控制技术进行闭环设计,提高了... 多工位输送机是一种可用在农药和化肥等农资产品纸塑包装后的装箱设备,其工作位置的定位要求快速准确,采用传统步进电机的开环控制难以达到要求。为此,以S7-300型PLC为平台,采用Fuzzy-Control软件运用模糊控制技术进行闭环设计,提高了设备定位的准确性。 展开更多
关键词 模糊控制 步进电机 位置控制 可编程序控制器(PLC)
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TNF-α and IL-1RA Polymorphisms and Silicosis Susceptibility in Chinese Workers Exposed to Silica Particles:A Case-Control Study 被引量:12
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作者 WANG Yong Wei LAN Ya Jia +2 位作者 YANG Yue Lin WANG De Jun KUANG Jie 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第5期517-525,共9页
Abstract Objective To assess the association of TNF-α and IL-1RA SNPs with the risk of silicosis in Chinese workers exposed to silica particles. Methods Case-control study design was used to enroll 68 silicotic patie... Abstract Objective To assess the association of TNF-α and IL-1RA SNPs with the risk of silicosis in Chinese workers exposed to silica particles. Methods Case-control study design was used to enroll 68 silicotic patients induced by silica particles and 68 healthy workers matched for length of silica particle exposure as controls. Both cases and controls were from the same company in southwest China, and each of them was requested to complete a questionnaire. Blood samples were drawn for genomic DNA extraction from each participant. The genotyping of TNF-α (-238 and -308) and IL-1RA (+2018) was performed using polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) and SYBR green-based quantitative polymerase chain reaction {qPCR), respectively. Unconditional logistic regression model was used to estimate odds ratios (ORs) and their 95% confidential intervals (Cl) for SNPs. Results No significant differences were found between cases and controls in particles exposure length, body mass index (BMI), and status of smoking and alcohol consumption except for age (P=O.O01) and blood type (P=0.042). The frequencies of TNF-c((-238) and IL-1RA (+2018) genotypes in cases were significantly different from those in controls, (P=O.O01 and P=0.O02, respectively), while a borderline significant difference was found in the frequencies of TNF-α(-308) between cases and controls (P=0.063). The variants of three SNPs increased the risk of silicosis in the Chinese workers exposed to silica particles. The adjusted ORs of TNFα(-308), TNF-α(-238) and IL-1RA (+2018) were 2.8 (95% Ch 2.1-7.5), 20.9 (95% Ch 2.8-236.4) and 4.0 (95% CI: 2.6-10.2), respectively. Conclusion It is suggested that cytokine polymorphisms of TNF-ct (-238, -308) and IL-1RA (+2018) are associated with the risk of silicosis in the Chinese workers exposed to silica particles. Further independent studies on the interaction between SNPs and exposure to silica particles with a larger sample size are therefore warranted. 展开更多
关键词 TNF-α IL-1RA POLYMORPHISM SILICOSIS Case-control study
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An Aware-Scheduling Security Architecture with Priority-Equal Multi-Controller for SDN 被引量:4
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作者 Chao Qi Jiangxing Wu +2 位作者 Guozhen Cheng Jianjian Ai Shuo Zhao 《China Communications》 SCIE CSCD 2017年第9期144-154,共11页
Current SDN controllers suffer from a series of potential attacks. For example, malicious flow rules may lead to system disorder by introducing unexpected flow entries. In this paper, we propose Mcad-SA, an aware deci... Current SDN controllers suffer from a series of potential attacks. For example, malicious flow rules may lead to system disorder by introducing unexpected flow entries. In this paper, we propose Mcad-SA, an aware decision-making security architecture with multiple controllers, which could coordinate heterogeneous controllers internally as a "big" controller. This architecture includes an additional plane, the scheduling plane, which consists of transponder, sensor, decider and scheduler. Meanwhile it achieves the functions of communicating, supervising and scheduling between data and control plane. In this framework, we adopt the vote results from the majority of controllers to determine valid flow rules distributed to switches. Besides, an aware dynamic scheduling(ADS) mechanism is devised in scheduler to intensify security of Mcad-SA further. Combined with perception, ADS takes advantage of heterogeneity and redundancy of controllers to enable the control plane operate in a dynamic, reliable and unsteady state, which results in significant difficulty of probing systems and executing attacks. Simulation results demonstrate the proposed methods indicate better security resilience over traditional architectures as they have lower failure probability when facing attacks. 展开更多
关键词 MULTI-controlLER security architec-ture aware SCHEDULING
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Model-View-Controller架构用于中医舌诊网络化教学 被引量:2
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作者 叶美玲 沈淑敏 +1 位作者 陈兴夏 廖福龙 《北京生物医学工程》 2007年第4期425-427,共3页
目的运用Model-View-Controller架构于因特网,设计与研发中医舌诊教学的网站。方法本因特网教学系统使用Websphere6.0服务器、DB28.1.7数据库、Java Server Faces、Structure Query Language、HTML以及JavaScript等共同开发而成。邀请8... 目的运用Model-View-Controller架构于因特网,设计与研发中医舌诊教学的网站。方法本因特网教学系统使用Websphere6.0服务器、DB28.1.7数据库、Java Server Faces、Structure Query Language、HTML以及JavaScript等共同开发而成。邀请85位大学护理学生参与测试。结果中医舌诊网站含盖八大相关部分。学习成效测试结果显示,网络教学方式可增加学生相关的专业知识。 展开更多
关键词 模式-显示-控制 舌诊 因特网
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A Novel Pre-control Method of Vehicle Dynamics Stability Based on Critical Stable Velocity during Transient Steering Maneuvering 被引量:9
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作者 CHEN Jie SONG Jian +3 位作者 LI Liang RAN Xu JIA Gang WU Kaihui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期475-485,共11页
The current research of direct yaw moment control(DYC) system focus on the design of target yaw moment and the distribution of wheel brake force. The differential braking intervention can effectively improve the lat... The current research of direct yaw moment control(DYC) system focus on the design of target yaw moment and the distribution of wheel brake force. The differential braking intervention can effectively improve the lateral stability of the vehicle, however, the effect of DYC can be improved a step further by applying the control of vehicle longitudinal velocity. In this paper, the relationship between the vehicle longitudinal velocity and lateral stability is studied, and the simulation results show that a decrease of 5 km/h of longitudinal velocity at a particular situation can bring 100° increasing of stable steering upper limit. A critical stable velocity considering the effect of steering and yaw rate measurement is defined to evaluate the risk of losing steer-ability or stability. A novel velocity pre-control method is proposed by using a hierarchical pre-control logic and is integrated with the traditional DYC system. The control algorithm is verified through a hardware in-the-loop simulation system. Double lane change(DLC) test results on both high friction coefficient(μ) and low μ roads show that by using the pre-control method, the steering effort in DLC test can be reduced by 38% and 51% and the peak value of brake pressure control can be reduced by 20% and 12% respectively on high μ and low μ roads, the lateral stability is also improved. This research proposes a novel DYC system with lighter control effort and better control effect. 展开更多
关键词 vehicle dynamics direct yaw moment control critical stable velocity pre-control
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Risk of Active Pulmonary Tuberculosis among Patients with Coal Workers'Pneumoconiosis:A Case-control Study in China 被引量:9
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作者 JIN Yan FAN Jing Guang +4 位作者 PANG Jing WEN Ke ZHANG Pei Ying WANG Huan Qiang LI Tao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第6期448-453,共6页
The aim of this study was to estimate the association between occupational, environmental, behavioral risk factors, and active pulmonary tuberculosis(PTB) among coal workers' pneumoconiosis(CWP) patients. A match... The aim of this study was to estimate the association between occupational, environmental, behavioral risk factors, and active pulmonary tuberculosis(PTB) among coal workers' pneumoconiosis(CWP) patients. A matched case-control study was conducted in 86 CWP patients with active PTB and 86 CWP controls without TB. A standardized questionnaire was used for risk factors assessment. Conditioned logistic regression analysis was used to identify associations between the risk factors and active PTB among CWP patients. The results showed that the stage of CWP, poor workplace ventilation, family history of TB, and exposure to TB were independent risk factors for active PTB in patients with CWP with which recommendations for improving work environments, and for case finding activities in patients with CWP could be made. 展开更多
关键词 Pulmonary tuberculosis Coal workers' pneumoconiosis RISK Case-control study
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