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P^2: a robust and rotationally invariant shape descriptor with applications to mesh saliency

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Applied Mathematics(A Journal of Chinese Universities) 2016年第1期31卷 53-67页

作者： liu Xian-yong MA li-zhuang liu li-gang School of Computer Science and Technology Shanghai Jiao Tong University

This work presents a robust and rotationally invariant shape descriptor, namely perception pronouncement （called p2）, to mathematically model the eye fixations, p2 takes two criteria - the local consideration of surface curvature and the global consideration of view- independent visibility - into account. Differing from existing works that often computed the intrinsic surface property of visibility in imaging space, a novel approach is proposed to approxi- mate the attribute in object space using Gauss map and Ray tracing. With the presented shape descriptor, mesh saliency detection, which refers to reasoning about which regions or points of a surface axe important, is more sensible, especially when 3D models fall into two categories：（1） the models possess significant interior/exterior structures; （2） the models contain regions where the contrast in visibility is high. For the models that are out of the categories, saliencies achieved by our approach are comparable to or even better than those of state-of-the-axt methods.

关键词： Human visual system mesh saliency shape descriptor bilateral filtering visibility.

Observer-based Output-feedback Stabilization Control Design for a Class of Nonlinear Uncertain Systems

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自动化学报 2006年第1期32卷 101-106页

作者： ZHANG Yun liu Yun-gang li Yan-Fang School of Control Science and Engineering Shandong University Jinan 250061

The output-feedback stabilization control problem is investigated for a class of nonlinear uncertain systems. Based on the multivariable analog of circle criterion, an observer is designed to estimate the system states and hence the dynamical equations that the estimation error satisfies are derived first. Then, by using integral backstepping approach together with completing square technique, the output-feedback stabilization control is constructively designed such that the closed-loop system is asymptotically stable. Finally, an example is given to illustrate the main results of this paper.

关键词：非线性系统不确定性输出反馈稳定性误差估计

钛表面电化学沉积氢氧化镁与氧化镁涂层的抗菌性能与生物活性

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硅酸盐学报 2024年第5期52卷 1570-1577页

作者：杜佳恒范鑫丽肖东琴刘刚利尹一然贺葵闫吉元李忠谭言飞段可西南医科大学附属医院骨与关节外科四川省骨科置入器械研发及应用技术工程实验室四川泸州646000 川北医学院第二临床学院南充市中心医院组织工程与干细胞研究所四川南充637000 山东大学齐鲁医学院口腔医学院口腔医院口腔颌面外科山东省口腔组织再生重点实验室山东省口腔生物材料与组织再生工程实验室山东省口腔疾病临床医学研究中心济南250012 四川大学生物材料工程研究中心成都610065

骨科植入物相关感染已严重影响手术效果及术后康复,因此需研究具备良好抗菌性能及生物活性的涂层。首先确定电化学沉积氢氧化镁[Mg(OH)_(2)]及氧化镁(MgO)涂层的制备条件,在钛表面沉积不同时间的Mg(OH)_(2)及MgO涂层,评价并比较2种涂层... 详细信息

骨科植入物相关感染已严重影响手术效果及术后康复,因此需研究具备良好抗菌性能及生物活性的涂层。首先确定电化学沉积氢氧化镁[Mg(OH)_(2)]及氧化镁(MgO)涂层的制备条件,在钛表面沉积不同时间的Mg(OH)_(2)及MgO涂层,评价并比较2种涂层的体外抗菌及生物相容性。各组样品表面均匀分布颗粒样物质[Mg(OH)_(2)及Mg O],颗粒密度与覆盖率随沉积时间增加。Mg(OH)2及MgO涂层对金黄色葡萄球菌及大肠杆菌均具良好抗菌性且抗菌率随沉积时间增强。沉积≤3 h,Mg O抑菌率显著高于Mg(OH)_(2);沉积≥6 h,两者`抑菌率均接近100%。Mg(OH)_(2)及MgO涂层细胞毒性随沉积时间上升,其中沉积0.5、1.0 h的2组样品毒性随培养时间下降,其余3组随培养时间上升。沉积0.5 h的Mg(OH)_(2)及MgO样品与细胞共培养5 d时的细胞存活率为152%、90%;沉积12 h的2组样品与细胞共培养5 d时细胞存活率为2%、6%。研究表明电化学沉积法可成功制备Mg(OH)_(2)涂层,且煅烧后可获得Mg O涂层。沉积1h的Mg(OH)_(2)及Mg O涂层样品具备良好抗菌性能的同时细胞毒性较小。

关键词：骨科植入物抗菌电化学沉积氢氧化镁氧化镁生物相容性

Fast color transfer from multiple images

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Applied Mathematics(A Journal of Chinese Universities) 2017年第2期32卷 183-200页

作者： KHAN Asad JIANG Luo li Wei liu li-gang Graphics and Geometric Computing Lab(GCL) School of Mathematical SciencesUniversityof Science and Technology of ChinaHefei 230026China.

Color transfer between images uses the statistics information of image effectively. We present a novel approach of local color transfer between images based on the simple statistics and locally linear embedding. A sketching interface is proposed for quickly and easily specifying the color correspondences between target and source image. The user can specify the corre- spondences of local region using scribes, which more accurately transfers the target color to the source image while smoothly preserving the boundaries, and exhibits more natural output results. Our algorithm is not restricted to one-to-one image color transfer and can make use of more than one target images to transfer the color in different regions in the source image. Moreover, our algorithm does not require to choose the same color style and image size between source and target images. We propose the sub-sampling to reduce the computational load. Comparing with other approaches, our algorithm is much better in color blending in the input data. Our approach preserves the other color details in the source image. Various experimental results show that our approach specifies the correspondences of local color region in source and target images. And it expresses the intention of users and generates more actual and natural results of visual effect.

关键词： robust color blending color style transfer locally linear embedding edit propagation subsampling image processing.

Tidal current turbine based on hydraulic transmission system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 511-518页

作者： Hong-wei liu Wei li Yong-gang liN Shun MA State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

Tidal current turbines(TCTs) are newly developed electricity generating *** at the stabilization of the power output of TCTs,this paper introduces the hydraulic transmission technologies into *** hydrodynamics of the turbine was analyzed at first and its power output characteristics were predicted.A hydraulic power transmission system and a hydraulic pitch-controlled system were *** related simulations were ***,a TCT prototype was manufactured and tested in the *** test results have confirmed the correctness of the current design and availability of installation of the hydraulic system in TCTs.

关键词： Tidal current turbines(TCTs) Hydraulic power transmission Hydraulic pitch-controlled system Workshop test

A giant primary myxoid liposarcoma of the posterior mediastinum

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Chinese Medical Journal 2010年第13期123卷 1818-1820页

作者： liu li-gang WEI Xiang PAN Tie-cheng Department of Cardiothoracic Surgery Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China

Primary mediastinal liposarcoma is an uncommon neoplasm of intrathoracic origin. A case of a giant primary posterior mediastinal liposarcoma, mimicking a benign lipomatous lesion in shape and biological behavior and b... 详细信息

关键词： mediastinal neoplasm liposarcoma radiology surgery

Dynamic Behavior of Entanglement Between Two Spatially Separated Atoms in Two Dissipative and Driven Cavity Fields

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Communications in Theoretical Physics 2009年第3期51卷 509-513页

作者： CUI Hui-Ping li Jian liu Jin li Jun-gang Department of Physics School of Science Beijing Institute of Technology Beijing 100081 China

We consider two two-level atoms, interacting with two independent dissipative cavities, each of which is driven by an external source. The two cavity fields are both initially prepared in the coherent states, and the two two-level atoms are initially prepared in the singlet state ｜ψ^-〉 =（｜eg〉 - ｜ge〉） / √2. We investigate the influence of the damping constant n, the intensity of the external sources F, and the relative difference of the atomic couplings r on the entanglement between the two atoms. In the dispersive approximation, we find that the entanglement between the two atoms decreases with the time evolution, and the decreasing rate of entanglement depends on the values of F/k, k/ω, and r. For the given small values of F/k and k/ω, on the one hand, the increasing of r favors entanglement decreasing of the atomic system, on the other hand, when r → 1 the entanglement decreasing becomes slower. With the increasing of the value of k/ω, the influence of r on the decreasing rate of entanglement becomes smaller, and gradually disappears for the big value of k/ω.

关键词： entanglement dissipation driven field

An armature structure for 3D shapes

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Applied Mathematics(A Journal of Chinese Universities) 2014年第4期29卷 422-437页

作者： JI Zhong-ping liu li-gang KIM Deok-soo School of Computer Science and Technology Hangzhou Dianzi University Graphics Geometric Computing Laboratory School of Mathematical Sciences University of Science and Technology of China Department of Industrial Engineering Hanyang University

We present a novel armature structure for 3D articulated shapes, called SBall short for skeletal balls, which includes two parts： a one-dimensional skeleton and incident balls. Our algorithm mainly focuses on constructing the armature structure. This structure is based on an approximation skeleton which is homotopy equivalent to the shape. Each ball in the structure connects a skeletal joint and an interior region of the shape. The boundary vertices on the shape surface are attached onto the SBall using the power diagram of the ball set. A bilateral O^tering algorithm and a variational segmentation algorithm are proposed to enhance the quality of SBall. Finally, applications of this structure are discussed.

关键词： armature structure prong feature thinning variational segmentation.

FLUID CHARACTERISTICS OF ROTARY WING HEAT METER WITH SINGLE-CHANNEL

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Journal of Hydrodynamics 2008年第1期20卷 101-107页

作者： Du Guang-sheng liu Zheng-gang li li liu Yong-hui MA Yong-kun MENG liang School of Energy and Power Engineering Shandong University Jinan 250061China

Fluid characteristics of a rotary wing heat meter with single-channel were studied through theretical analysis, numerical simulation and experiments. The obtained results show that the number of vanes can obviously influence the heat meter, but the water temperature seldom influence the meter , and the optimal number of vane is 6-8.

关键词： heat meter numerical simulation meter