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A new real-time eye tracking based on nonlinear unscented Kalman filter for monitoring driver fatigue

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控制理论与应用（英文版） 2010年第2期8卷 181-188页

作者： Zutao ZHANG 1 , 2 , Jiashu ZHANG 2 (1.School of Mechanical Engineering, southwest Jiaotong University, Chengdu Sichuan 61003., China 2.Sichuan Key Lab of Signal and Information Processing, southwest Jiaotong University, Chengdu Sichuan 61003., China) School of Mechanical Engineering Southwest Jiaotong University Chengdu Sichuan China Sichuan Key Lab of Signal and Information Processing Southwest Jiaotong University Chengdu Sichuan China

A new scheme for driver fatigue detection is presented, which is based on the nonlinear unscented Kalman filter and eye tracking. Assuming a probability distribution than to approximate an arbitrary nonlinear function or transformation, eye nonlinear tracking can be achieved using an unscented transformation (UT), which adopts a set of deterministic sigma points to match the posterior probability density function of the eye movement. Driver fatigue can be detected using the percentage of eye closure (PERCLOS) framework in a realistic driving condition after the eye nonlinear tracking. This system was tested adequately in realistic driving environments with subjects of different genders, with/without glasses, in day/night driving, being commercial/noncommercial drivers, in continuous driving time, and under different road conditions. The last experimental results show that the proposed method not only improves the robustness for nonlinear eye tracking, but also can provide more accurate estimation than the traditional Kalman filter.

关键词： Eye tracking Unscented Kalman filter (UKF) Fatigue detection PERCLOS

The Formation Mechanism of Hydrogeochemical Features in a Karst System During Storm Events as Revealed by Principal Component Analysis

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地学前缘 2009年第S1期16卷 33-34页

作者： Pingheng Yang Daoxian Yuan Kuang Yinglun,Wenhao Yuan,Peng Jia,Qiufang He 1.School of Geographical Sciences,southwest University,Chongqing 400715,China. 2.Laboratory of Geochemistry and Isotope,southwest University,Chongqing 400715,China 3.The Karst Dynamics Laboratory,Ministry of Land and Resources,Institute of Karst Geology,Chinese Academy of Geological Sciences,Guilin 541004,China

The hydrogeochemical parameters of Jiangjia Spring,the outlet of Qingrnuguan underground river system(QURS) in Chongqing,were found responding rapidly to storm events in late April,2008.A total of 20 kinds of hydrogeo... 详细信息

关键词： rainfall principal component analysis(PCA) soil erosion agricultural activities karst hydrogeochemical feature Qingmuguan

Algorithms for Assembly Type Flowshop Scheduling Problem

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Journal of Modern Transportation 2000年第1期17卷 99-105页

作者：李晓渝晋一关秦川 School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031 China Shool of Gold Industry San Men Xia 472000 China Institute of Mechanics Engineering Southwest Jiaotong University Chengdu 610031 China

An assembly type flowshop scheduling problem with minimizing makespan is considered in this paper. The problem of scheduling for minimizing makespan is first addressed, and then a new heuristic algorithm is proposed ... 详细信息

关键词： flowshop scheduling assembly type production algorithm makespan

Experimental Study on Uniaxial and Multiaxial Strain CyclicCharacteristics and Ratcheting of 3.6L Stainless Steel

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Journal of Materials Science & Technology 2001年第2期17卷 219-223页

作者： GuoZheng KANG, Qing GAO, Lixun CAI, Xianjie YANG and Yafang SUN Department of Applied Mechanics and Engineering, southwest Jiaotong University, Chengdu 61003., China SW Jiaotong Univ Dept Appl Mech & Engn Chengdu 610031 Peoples R China

An experimental study was carried out on the strain cyclic characteristics and ratcheting of 3.6L stainless steel subjected to uniaxial and multiaxial cyclic loading. The strain cyclic characteristics were researched under the strain-controlled uniaxial tension-compression and multiaxial circular paths of loading. The ratcheting tests were conducted for the stress-controlled uniaxial tension-compression and multiaxial circular, rhombic and linear paths of loading with different mean stresses, stress amplitudes and histories. The experiment results show that 3.6L stainless steel features the cyclic hardening, and its strain cyclic characteristics depend on the strain amplitude and its history apparently. The ratcheting of 3.6L stainless steel depends greatly on the Values of mean stress, stress amplitude and their histories. In the meantime, the shape of load path and its history also apparently influence the ratcheting.

关键词： Experimental Study on Uniaxial and Multiaxial Strain CyclicCharacteristics and Ratcheting of 3.6L Stainless Steel

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利用数据融合实现流型的在线识别

天然气工业 2004年第12期24卷 68-70页

作者：党民熊继有李井矿廖仕孟韩波曾汇川西南石油学院"油气藏地质及开发工程"国家重点实验室华北石油管理局第二钻井工程公司中国石油西南油气田分公司

两相流的流动是一个复杂的多变量随机过程。认识流型的形成机理和特征以及流动规律一直是两相流领域的重要研究方向。传统的流型识别方法 (流型图和流型转换判别 )能够预测流型及其转换 ,但是要应用它来获取流体的实时流动参数还是有较... 详细信息

两相流的流动是一个复杂的多变量随机过程。认识流型的形成机理和特征以及流动规律一直是两相流领域的重要研究方向。传统的流型识别方法 (流型图和流型转换判别 )能够预测流型及其转换 ,但是要应用它来获取流体的实时流动参数还是有较大的难度。而在石油天然气工程 (钻井、固井、集输管道等 )应用实际中 ,往往需要实时了解流动参数以确定系统的运行状况。针对这个问题 ,为掌握实时流动参数的特性而进行了较深入的研究。文章提出了一种基于数据融合理论两相流流型识别新方法 ,并设计了流型的在线识别系统。研究结果表明 ,该识别方法具有置信度高 ,容错性好 ,性能稳定 ,减小了传感器的不确定误差 ,降低了单个传感器的性能要求等优点。这种方法对两相流流型具有实时识别的能力。

关键词：实时在线识别数据融合容错性不确定流型识别传感器集输管道固井钻井

重庆安澜鹭类自然保护区和三峡库区鸟类资源比较研究

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西南师范大学学报（自然科学版） 2004年第6期29卷 1032-1036页

作者：彭筱葳曾波西南师范大学生命科学学院 .西南师范大学三峡库区生态环境教育部重点实验室重庆400715 西南师范大学重庆市三峡库区植物生态与资源重点实验室重庆400715

对安澜自然保护区和三峡库区的鸟类资源进行了比较分析,结果发现:从数量上看,安澜自然保护区共有鸟类89种,三峡库区有鸟类3.1种;从生境上看,安澜自然保护区农田生境鸟类最多(3..25%),三峡库区农田和水域生境鸟类最多(分别为3..19%... 详细信息

对安澜自然保护区和三峡库区的鸟类资源进行了比较分析,结果发现:从数量上看,安澜自然保护区共有鸟类89种,三峡库区有鸟类3.1种;从生境上看,安澜自然保护区农田生境鸟类最多(3..25%),三峡库区农田和水域生境鸟类最多(分别为3..19%和3..3.%);从居留类型上看,安澜自然保护区有候鸟3.种(3..20%),留鸟53. 种(59.55%),三峡库区有候鸟140种(42.3.%),留鸟148种(44.71%);从区系上看,安澜自然保护区以东洋界成分为主(47.19%),三峡库区以东洋界和古北界成分为主(分别为46.83.和42.90%).两地区鸟类相似性系数为 0.27,鹭科物种相似性系数达到0.64.根据安澜自然保护区的实际情况和现状,对加强安澜鹭类自然保护区的建设工作提出了相关建议.

关键词：鸟类资源候鸟东洋界物种相似性自然保护区区系生境三峡库区农田相似性系数

THE PROPAGATION OF ELASTIC STRESS WAVES IN A CONICAL SHELL UNDER AXIAL IMPULSIVE LOADING

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Acta Mechanica Sinica 1987年第2期3卷 173-186页

作者： Chen Yuze Le Guopei Jing Erli Xue Jindi (southwest Institute of Structural Mechanics) 四川绵阳中国工程物理研究院结构力学所，621900 四川绵阳中国工程物理研究院结构力学所，621900 四川绵阳中国工程物理研究院结构力学所，621900 四川绵阳中国工程物理研究院结构力学所，621900

The propagation of elastic stress waves in a conical shell subjected to axial impulsiveloading is studied in this paper by means of the finite element calculation and model *** shown that there are two axisymmetrical elastic stress waves propagating with different velocities,i.e.,the longitudinal wave and the bending *** attenuation of these waves while propagatingalong the shell surface is *** is found in experiments that the bending wave is also,generatedwhen a longitudinal wave reflects from the fixed end of the shell,and both reflected waves willseparate during the propagation due to their different velocities.

关键词： elastic stress wave bending wave logitudinal wave axial impulsive loading

Application of Separable Perforating-Fracturing Combined Bullet to the Test of Oil and Gas Wells

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天然气工业 1996年第3期16卷 114-116页

作者： Li Jianliang Li Hengrang (southwest Petroleum Geology Bureau of the Ministry of Geology and Mineral Resources)

Along with the progress of thetechnique of oil-gas field devel-opment, an attention is generallypaid to the formation damage bydrilling and well cementing inprocess of well completion. Inthe end of 1980s, the petroleumenterprises have introduced theperforating bullets from Schlumberger and Hal-liburton, co. Through their contrast and test withthose manufactured in China, it is considered thatthe Schlumberger’s deep perforating bullets can e-liminate the damage by drilling and raise oil pro-duction. The test in Moxi and Bajiochang gas fieldsin Sichuan indicated that the oil and gas productionfrom carbonate and sandstone reservoirs obviouslyincreased. Therefore, the importance to the study

关键词： Application of Separable Perforating-Fracturing Combined Bullet to the Test of Oil and Gas Wells test Test

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天然气欠平衡钻井技术在井浅2井的应用

天然气工业 2005年第2期25卷 72-74页

作者：赵大鹏石晓兵王蓉先杨国懿李烈明郑家伟 '油气藏地质及开发工程'国家重点实验室.西南石油学院西南油气田分公司蜀南气矿四川石油管理局

天然气欠平衡钻井就是在钻开产层前采用天然气作为钻井介质,替换普通泥浆进行钻井作业,在钻井过程中井筒气柱压力低于地层压力,允许地层流体进入井筒,没有钻井液滤液和有害固相微粒进入地层。它与其它欠平衡钻井作业方式相比,具有鲜明... 详细信息

天然气欠平衡钻井就是在钻开产层前采用天然气作为钻井介质,替换普通泥浆进行钻井作业,在钻井过程中井筒气柱压力低于地层压力,允许地层流体进入井筒,没有钻井液滤液和有害固相微粒进入地层。它与其它欠平衡钻井作业方式相比,具有鲜明的技术特点和独特的技术优势,是一种对于产层少污染的非常规钻井方式,是真实评价和最好保护油气层的最佳钻井方法。文章结合井浅 2 井,重点介绍了有关天然气欠平衡钻井的一些关键技术,主要包括储层特征、井身结构、钻具组合、气举、天然气钻进技术、不压井带压起下钻技术、不压井带压下油管技术等,并列举了天然气欠平衡钻井在该井所取得的主要技术成果。井浅 2 井首次在南井构造须家河组获得油气储量,实现了该构造须家河组油气勘探开发的重大突破。为勘探开发川南水敏伤害严重的低压碎屑岩储层找到了一种有效的技术手段。

关键词：欠平衡钻井技术压井天然气保护油气层钻井过程水敏钻井方式油气储量油气勘探开发技术优势