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Explicit G2-constrained Merging of a Pair of Bezier Curves by Control Point Optimization

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自动化学报 2014年第7期40卷 1505-1508页

作者： lu li-zheng QIU Yu-Yang School of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 China

This paper presents a simple and explicit method for G~2-constrained merging of a pair of Bezier curves by minimizing the l_2 distance defined in terms of control points. After expressing the l_2 distance as a quadratic function of two parameters, the optimally merged curve can be explicitly obtained, which is achieved by control point optimization such that the l_2 distance is minimized. The existence of the unique solution is shown by proving that the l_2 distance is convex. The proposed method is explicit and efficient since it is non-iterative and expressed by known control points. Numerical examples demonstrate the effectiveness of the new method.

关键词：贝塞尔曲线控制点合并 G2 优化二次函数距离最小化

Management of venous stenosis in living donor liver transplant recipients

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World Journal of Gastroenterology 2009年第39期15卷 4969-4973页

作者： Jie Yang Ming-Qing Xu lu-Nan Yan Wu-Sheng lu Xiao li zheng-Rong Shi Bo li Tian-Fu Wen Wen-Tao Wang Jia-Ying Yang Department of liver and Vascular Surgery West China Hospital Sichuan University Chengdu 610041 Sichuan Province China

AIM:To retrospectively evaluate the management and outcome of venous obstruction after living donor liver transplantation(LDLT).METHODS:From February 1999 to May 2009,1 intraoperative hepatic vein(HV) tension induced HV obstruction and 5 postoperative HV anastomotic stenosis occurred in 6 adult male LDLT *** portal vein(PV) anastomotic stenosis occurred in 1 pediatric left lobe *** ranged in age from 9 to 56 years(median,44 years).An air balloon was used to correct the intraoperative HV *** surgical reoperation,transjugular HV balloon dilatation with stent placement and transfemoral venous HV balloon dilatation was performed for HV stenosis on days 3,15,50,55,and 270 after LDLT,*** dilatation followed with stent placement via superior mesenteric vein was performed for the pediatric PV stenosis 168 d after ***:The intraoperative HV tension was corrected with an air *** recipient who underwent emergent reoperation for hepatic stenosis died of hemorrhagic shock and renal failure 2 d *** balloon dilatation via the transjugular and transfemoral venous approach was technically successful in all *** patient with early-onset HV stenosis receiving transjugular balloon dilatation and stent placement on the 15th postoperative day left hospital 1 wk later and disappeared,while the patient receiving the same interventional procedures on the 50th postoperative day died of graft failure and renal failure 2 wk *** patients with late-onset HV stenosis receiving balloon dilatation have survived for 8 and 4 mo without recurrent stenosis and ascites,*** dilatation and stent placement via the superior mesenteric venous approach was technically successful in the pediatric left lobe LDLT,and this patient has survived for 9 mo without recurrent PV stenosis and ***:Intraoperative balloon placement,emergent reoperation,proper interventional balloon dilatation and

关键词： living donor liver transplantation Venous obstruction Anastomotic stenosis Venoplasty Stent

Properties of a family of merit functions and a merit function method for the NCP

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Applied Mathematics(A Journal of Chinese Universities) 2010年第4期25卷 379-390页

作者： lu li-yong HUANG zheng-hai HU Sheng-long Department of Mathematics, School of Science, Tianjin University, Tianjin 300072, China Department of Mathematics School of Science Tianjin University Tianjin China

A family of merit functions are proposed, which are the generalization of several existing merit functions. A number of favorable properties of the proposed merit functions are established. By using these properties, a merit function method for solving nonlinear complementarity problem is investigated, and the global convergence of the proposed algorithm is proved under some standard assumptions. Some preliminary numerical results are given.

关键词： Nonlinear complementarity problem NCP-function merit function merit function method.

Microarray Scanner for Fluorescence Detection

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光学学报 2003年第S1期23卷 829-830页

作者： Wang liqiang, lu zukang, li Yingsheng .zheng Xufeng Optical Engineering Department of Zhejiang University, Hangzhou, P.R.China Optical Engineering Department of Zhejiang University Hangzhou P.R.China

A novel pseudo confocal microarray scanner is introduced, in which one dimension scanning is performed by a galvanometer optical scanner and a telecentric objective, another dimension scanning is performed by a steppi... 详细信息

关键词： for of is Microarray Scanner for Fluorescence Detection PMT

日照市区PM_(10)污染物特征及其与气象要素的关系

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南京气象学院学报 2006年第3期29卷 413-417页

作者：郑美琴卢振礼日照市气象局山东日照276826

对2002年1月1日—2002年12月31日日照市环境监测中心提供的PM10(可吸入颗粒物)日平均浓度资料和对应时段的日照市地面气象资料做了深入的分析,揭示了污染物PM10变化特征及其随气象要素的变化规律。同时分析了主要污染物PM10与地面风速... 详细信息

对2002年1月1日—2002年12月31日日照市环境监测中心提供的PM10(可吸入颗粒物)日平均浓度资料和对应时段的日照市地面气象资料做了深入的分析,揭示了污染物PM10变化特征及其随气象要素的变化规律。同时分析了主要污染物PM10与地面风速、风向间的相关关系,发现日照市大于等于3级的PM10污染日均出现在1—4月,地面风速对污染物PM10浓度有一定影响,当地面风速超过5 m/s时,3级及以上污染日很少出现,当地面风速超过6.5 m/s时,随着风速的提高,污染物浓度呈下降趋势。污染物浓度呈明显的季节变化,冬、春季节明显高于夏、秋季节。

关键词： PM10 变化特征气象要素

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二次带形状参数双曲B样条曲线

高校应用数学学报（A辑） 2008年第1期23卷 105-111页

作者：陆利正汪国昭浙江大学数学系浙江杭州310027

在空间Ω_5=span{1,sinh t,cosh t,sinh 2t,cosh 2t}上给出了二次带形状参数双曲B样条的基函数.由这组基组成的二次双曲B样条曲线是C^1连续的,同时具有很多与二次B样条曲线类似的性质和几何结构,并且可以精确表示双曲线.在控制多边形固... 详细信息

在空间Ω_5=span{1,sinh t,cosh t,sinh 2t,cosh 2t}上给出了二次带形状参数双曲B样条的基函数.由这组基组成的二次双曲B样条曲线是C^1连续的,同时具有很多与二次B样条曲线类似的性质和几何结构,并且可以精确表示双曲线.在控制多边形固定的情况下,可以通过调节形状参数的大小来进一步调整曲线的形状.

关键词： B样条曲线基函数双曲形状参数

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong li Peng Ai Wanrong Guo Tuo zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

地震作用设计参数调整对框架结构抗震设计及安全性的影响

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工程力学 2017年第4期34卷 22-31页

作者：卢啸陆新征李梦珂顾栋炼解琳琳北京交通大学土木建筑工程学院北京100044 清华大学土木工程系北京100084 中国建筑设计院有限公司北京100044 北京建筑大学土木与交通工程学院北京100044

汶川、芦山等大地震震害经验表明:地震中建筑遭受的实际烈度经常远高于规范规定的设防烈度,这导致建筑结构在地震中受到非常严重的破坏。虽然随着规范的改进和新的设防区划图的提出,我国建筑抗震的安全水准在不断提升,但是很多专家仍认... 详细信息

汶川、芦山等大地震震害经验表明:地震中建筑遭受的实际烈度经常远高于规范规定的设防烈度,这导致建筑结构在地震中受到非常严重的破坏。虽然随着规范的改进和新的设防区划图的提出,我国建筑抗震的安全水准在不断提升,但是很多专家仍认为目前建筑结构的抗震安全储备偏低。因此,确定合理的地震作用对保证建筑结构的抗震安全性有重要意义。该文以基于2010版《建筑抗震设计规范》设计的一系列钢筋混凝土框架结构为研究对象,通过调整地震动力放大系数、地震作用和荷载分项系数等参数的取值,对框架进行重设计,并对框架结构进行倒塌分析,研究地震作用设计参数调整对框架结构的设计控制指标、地震力、材料用量和抗震安全性造成的影响。研究结果表明:调整措施将使底层柱轴压比增大约8%;楼板和框架梁的钢筋用量提高约6%;对初始破坏始于底层的倒塌模式,调整措施能明显提高结构的抗震安全性,但随着设防烈度提高,地震下抗倒塌能力的提高程度略有降低。

关键词：地震作用钢筋混凝土框架轴压比倒塌分析抗震安全性

A Novel Self-Supervised Learning Network for Binocular Disparity Estimation

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 209-229页

作者： Jiawei Tian Yu Zhou Xiaobing Chen Salman A.AlQahtani Hongrong Chen Bo Yang Siyu lu Wenfeng zheng Department of Computer Science and Engineering Major in Bio Artificial IntelligenceHanyang UniversityAnsan-si15577Republic of Korea School of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA 70803USA Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh11574Saudi Arabia School of Automation University of Electronic Science and Technology of ChinaChengdu610054China

Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical *** study proposes a novel end-to-end disparity estimation model to address these *** approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting *** study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and *** model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video *** results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing ***,the model exhibited faster convergence during training,contributing to overall performance *** study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments.

关键词： Parallax estimation parallax regression model self-supervised learning Pseudo-Siamese neural network pyramid dilated convolution binocular disparity estimation