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关键词

Lagrangian松弛 1

McCormick包络 1

中断模型；k-可靠性；对偶；线性规划松弛；互补松弛型 1

优化运行 1

全局优化 1

凸松弛 1

分段线性松弛 1

多目标优化决策模型 1

多符号差分检测；广义似然比检验；半定松弛；双向中继传输 1

无线信息与能量同时传输；信道状态信息；鲁棒波束形成；半定松弛；迭代次梯度 1

时间—资源权衡协调 1

热电联合系统 1

状态估计；克拉美罗下界；可行解追逐；半正定松弛；近线性算法；复合优化；网络攻击；坏数据检测 1

空间拦截问题；变分法；多约束；两速度脉冲；多点边值问题；局部最优解；动态松弛变量法 1

连续时间调合模型 1

非线性汽油调合 1

项目时间表 1

项目计划管理 1

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时间—资源权衡协调问题的多目标优化决策模型

王先甲,万仲平

《中国工程科学》 2005年第7卷第2期页码 35-40

摘要：此外，在对应于资源约束的Lagrangian松弛表示式中，给出了该二人对策问题的有关特性。

关键词：项目计划管理时间—资源权衡协调多目标优化决策模型项目时间表 Lagrangian松弛

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Investigation of vortical flows over oscillating body using fast Lagrangian vortex method

Baoshan ZHU ,

《能源前沿（英文）》 2009年第3卷第3期页码 297-306 doi: 10.1007/s11708-009-0010-4

摘要： A computational method facilitating long-time and high-resolution unsteady vortical flows is developed with the advantages of the discrete vortex methods. Both the velocity and pressure distribution of the flow field are calculated by integral formulations in combination with a fast summation algorithm. The vorticity field is described by Lagrangian representation, which is well suited to the moving boundary. Viscosity diffusion of the vorticity is considered with the core spreading model corrected by an adaptive splitting and merging algorithm. The effectiveness of the present method is examined by comparing the numerical results of unsteady separated flows which pass a cylinder and a thin cambered blade undergoing rotational oscillations with available experimental results. Interesting results about vortex shedding patterns and lock-in characteristics are provided for the thin cambered blade.

关键词： unsteady vortical flows fast vortex method vortex shedding rotational oscillation thin cambered blade

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Implementation of total Lagrangian formulation for the elasto-plastic analysis of plane steel frames

Bing XIA, Yuching WU, Zhanfei HUANG

《结构与土木工程前沿（英文）》 2012年第6卷第3期页码 257-266 doi: 10.1007/s11709-012-0163-9

摘要： In this paper, the co-rotational total Lagrangian forms of finite element formulations are derived to perform elasto-plastic analysis for plane steel frames that either experience increasing external loading at ambient temperature or constant external loading at elevated temperatures. Geometric nonlinearities and thermal-expansion effects are considered. A series of programs were developed based on these formulations. To verify the accuracy and efficiency of the nonlinear finite element programs, numerical benchmark tests were performed, and the results from these tests are in a good agreement with the literature. The effects of the nonlinear terms of the stiffness matrices on the computational results were investigated in detail. It was also demonstrated that the influence of geometric nonlinearities on the incremental steps of the finite element analysis for plane steel frames in the presence of fire is limited.

关键词： co-rotational total Lagrangian geometrical nonlinearity fire elasto-plastic

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Lagrangian simulation of deposition of CO gas-solid sudden expansion flow

HUANG Dongping, DING Guoliang, QUACK Hans

《能源前沿（英文）》 2008年第2卷第2期页码 216-221 doi: 10.1007/s11708-008-0032-3

摘要： Freezing and blockage resulting from the deposition of solid CO formed because of sudden expansion of the downstream pipe during the release of CO through safety valves, will endanger the protected equipment. To overcome this problem, the characteristics of the CO gas-solid sudden expansion flow are studied by using the disperse Lagrangian model. A comparison of the calculated deposition of the solid CO with the experimental results shows that they are in reasonable agreement. The simulation results show that the size of the solid CO formed should not be in the range of 0.04–0.07 mm ( number 3.2–9.8). This can be achieved by using an appropriate flow cross section of the safety valve.

关键词： comparison gas-solid downstream blockage Lagrangian

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based highly undersampled MR image reconstruction using patch-based constraint splitting augmented Lagrangian

Min YUAN,Bing-xin YANG,Yi-de MA,Jiu-wen ZHANG,Fu-xiang LU,Tong-feng ZHANG

《信息与电子工程前沿（英文）》 2015年第16卷第12期页码 1069-1087 doi: 10.1631/FITEE.1400423

摘要： Recently, dictionary learning (DL) based methods have been introduced to compressed sensing magnetic resonance imaging (CS-MRI), which outperforms pre-defined analytic sparse priors. However, single-scale trained dictionary directly from image patches is incapable of representing image features from multi-scale, multi-directional perspective, which influences the reconstruction performance. In this paper, incorporating the superior multi-scale properties of uniform discrete curvelet transform (UDCT) with the data matching adaptability of trained dictionaries, we propose a flexible sparsity framework to allow sparser representation and prominent hierarchical essential features capture for magnetic resonance (MR) images. Multi-scale decomposition is implemented by using UDCT due to its prominent properties of lower redundancy ratio, hierarchical data structure, and ease of implementation. Each sub-dictionary of different sub-bands is trained independently to form the multi-scale dictionaries. Corresponding to this brand-new sparsity model, we modify the constraint splitting augmented Lagrangian shrinkage algorithm (C-SALSA) as patch-based C-SALSA (PB C-SALSA) to solve the constraint optimization problem of regularized image reconstruction. Experimental results demonstrate that the trained sub-dictionaries at different scales, enforcing sparsity at multiple scales, can then be efficiently used for MRI reconstruction to obtain satisfactory results with further reduced undersampling rate. Multi-scale UDCT dictionaries potentially outperform both single-scale trained dictionaries and multi-scale analytic transforms. Our proposed sparsity model achieves sparser representation for reconstructed data, which results in fast convergence of reconstruction exploiting PB C-SALSA. Simulation results demonstrate that the proposed method outperforms conventional CS-MRI methods in maintaining intrinsic properties, eliminating aliasing, reducing unexpected artifacts, and removing noise. It can achieve comparable performance of reconstruction with the state-of-the-art methods even under substantially high undersampling factors.

关键词： Compressed sensing (CS) Magnetic resonance imaging (MRI) Uniform discrete curvelet transform (UDCT) Multi-scale dictionary learning (MSDL) Patch-based constraint splitting augmented Lagrangian shrinkage algorithm (PB C-SALSA)

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有限资源下最大可靠性网络流中断模型

赵佳,于华

《中国工程科学》 2015年第17卷第1期页码 137-142

摘要：在给定图中，两点之间的路的条数是图的规模的指数次幂，为此将此模型转化为双层整数规划模型，鉴于双层整数规划模型在一般情况下是不可解的，通过探讨下层整数规划问题与其线性规划松弛之间的关系以及线性规划对偶理论来解此双层整数规划模型

关键词：中断模型；k-可靠性；对偶；线性规划松弛；互补松弛型

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Design and evaluation of a novel biopsy needle with hemostatic function

《机械工程前沿（英文）》 2023年第18卷第2期 doi: 10.1007/s11465-022-0738-7

摘要： Biopsy is a method commonly used for early cancer diagnosis. However, bleeding complications of widely available biopsy are risky for patients. Safer biopsy will result in a more accurate cancer diagnosis and a decrease in the risk of complications. In this article, we propose a novel biopsy needle that can reduce bleeding during biopsy procedures and achieve stable hemostasis. The proposed biopsy needle features a compact structure and can be operated easily by left and right hands. A predictive model for puncture force and tip deflection based on coupled Eulerian–Lagrangian (CEL) method is developed. Experimental results show that the biopsy needle can smoothly deliver the gelatin sponge hemostatic plug into the tissue. Although the hemostatic plug bends, the overall delivery process is stable, and the hemostatic plug retains in the tissue without being affected by the withdrawal of the needle. Further experiments indicate that the specimens are well obtained and evenly distributed in the groove of the outer needle without scattering. Our proposed design of biopsy needle possesses strong ability of hemostasis, tissue cutting, and tissue retention. The CEL model accurately predicts the peak of puncture force and produces close estimation of the insertion force at the postpuncture stage and tip position.

关键词： cancer diagnosis biopsy needle hemostatic function predictive model coupled Eulerian−Lagrangian

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双向中继传输中基于半定松弛的非相干检测 Regular Papers-Research Articles

Chan-fei WANG, Ji-ai HE, Wei-fang WANG, Ya-mei XU

《信息与电子工程前沿（英文）》 2019年第20卷第9期页码 1259-1265 doi: 10.1631/FITEE.1800096

摘要：进一步转换GLRT-MSDD，得到基于半定松弛的多符号差分检测（SDR-MSDD），此转化过程降低了算法实现的复杂度。

关键词：多符号差分检测；广义似然比检验；半定松弛；双向中继传输

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Simulation analysis of environmental risk accident and management of high-sulfur gas field development in complex terrain

WANG Xiao, HAO Fanghua, ZHANG Xuan, SUN Wen, CHENG Hongguang

《环境科学与工程前沿（英文）》 2008年第2卷第3期页码 318-325 doi: 10.1007/s11783-008-0033-9

摘要： Environmental risk of high sulfur gas field exploitation has become one of the hot spots of environmental management studies. Severe gas HS blowout accidents in recent years have shown that poor understanding and estimates of the poisonous gas movement could lead to dangerous evacuation delays. It is important to evaluate the real concentration of HS, especially in complex terrain. Traditional experiential models are not valid in the case of rough terrain, especially in low-lying areas where the gas accumulates. This study, using high sulfur content gas field of Sichuan “Pu Guang gas field” as study object and adopting objective diagnosis of wind field of land following coordinate three dimensions, applied Lagrangian Puff Model and breaking up technique of puffs to simulate the HS diffusion condition of blowout accidents produced in the high sulfur content gas field of complex terrain area. The results showed that the HS distribution did not occur mainly in low wind direction, and due to the obstruction of the mountain’s body, it accumulated in front of mountain on produced turn over, flowed around submitted jumping type distribution. The mountain waist near the hilltop and low hollow river valley site rapture points simulating contrast showed that the higher the rapture point, the better the diffusing condition of pollutant, the distribution of risk sensitive point decided piping rupture environmental risk size combining the HS diffusion result and residential area dispersing in the study area, synthetic judge located in the high rapture point environmental risk was smaller than the low hollow point, thus it was suggested to carryout laying of lining build of equal high line of higher terrain. According to simulation results, the environmental risk management measures aimed at putting down adverse effects were worked out.

关键词： mountain ’ rapture Lagrangian hollow produced

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非线性调合调度问题的全局优化

Pedro A. Castillo Castillo Pedro M. Castro,Vladimir Mahalec

《工程（英文）》 2017年第3卷第2期页码 188-201 doi: 10.1016/J.ENG.2017.02.005

摘要：该模型包含调合配方优化、分配问题及若干操作特性和约束；算法上采用分段McCormick 松弛(PMCR) 和规范多参数解聚(NMDT)，计算全局最优解的估计值，其松弛技术将双线性项中的一个变量值域进行分割，进而在每一个分段上产生凸松弛；通过增加分段数和缩减变量的值域，提高对全局最优解的估计。

关键词：全局优化非线性汽油调合连续时间调合模型分段线性松弛

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A solution to unit commitment problem using invasive weed optimization algorithm

B. SARAVANAN, E. R. VASUDEVAN, D. P. KOTHARI

《能源前沿（英文）》 2013年第7卷第4期页码 487-494 doi: 10.1007/s11708-013-0279-1

摘要： Unit commitment (UC) is one of the most important aspect of power generation in the world today. Though, there is no method to find the exact optimized solution, there exists several meta-heuristic algorithms to determine the close to exact solution. This paper proposes a novel solution to effectively determine UC and generation cost using the technique of invasive weed optimization (IWO). The existing technique distributes the load demand among all the generating units. The method proposed here utilizes the output of UC obtained by using the Lagrangian relaxation (LR) method and calculates the required generation from only the plants that are ON discarding the OFF generator units and thereby giving a faster and more accurate response. Moreover, the results show the comparison between the LR-particle swarm optimization (PSO) and LR-IWO, and prove that the cost of generation for a 4 unit, 8 hour schedule is much less in the case of IWO when compared to PSO.

关键词： Lagrangian relaxation (LR) invasive weed optimization (IWO) economic dispatch optimization fuel cost seed fitness

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多约束条件下的最优两脉冲空间拦截 Research Articles

谢力1,张奕群2,徐俊艳2

《信息与电子工程前沿（英文）》 2020年第21卷第7期页码 963-1118 doi: 10.1631/FITEE.1800763

摘要：为使用拉格朗日乘子法，采用松弛变量法将所有不等式约束转化为等式约束。为此提出一种新的动态松弛变量法，并建立一种间接优化方法。随后，用所提方法解决自由飞行弹道导弹的两脉冲空间拦截问题。

关键词：空间拦截问题；变分法；多约束；两速度脉冲；多点边值问题；局部最优解；动态松弛变量法

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基于紧缩McCormick方法的热电联合系统优化调度策略 Article

邓莉荣, 孙宏斌, 李宝聚, 孙勇, 阳天舒, 张璇

《工程（英文）》 2021年第7卷第8期页码 1076-1086 doi: 10.1016/j.eng.2021.06.006

摘要：现有的方法，如非线性优化、广义Benders分解方法和凸松弛技术等，在求解质量和计算性能上仍然存在不足。为了松弛联合调度模型中剩余的双线性项，文中采用McCormick包络的凸松弛方法，得到了联合调度模型的目标函数下界。为了提高McCormick松弛的质量，文中提出了一种紧缩McCormick的方法：首先，采用分段McCormick技术，将双线性项中一个变量的可行域划分为几个不相交的区域，通过求解此优化问题可以选出最优解所在的区域

关键词：热电联合系统凸松弛优化运行 McCormick包络

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智能电网状态估计方法最新进展综述 Review Article

Gang WANG, Georgios B. GIANNAKIS, Jie CHEN, Jian SUN

《信息与电子工程前沿（英文）》 2019年第20卷第1期页码 4-17 doi: 10.1631/FITEE.1800590

摘要：随着大量不确定可再生能源注入、大规模工业和个体用户市场参与、恶意智能仪表数据篡改等，精确、快速、鲁棒的状态估计方法对未来智能电网系统变得尤为重要。然而，目前电力系统采用的数据采集与监视控制系统只能获取系统状态（即系统所有节点的电压相量）的非线性测量数据。最新智能电网状态估计研究正着力于解决非线性测量数据带给可扩展性状态估计方法建模和计算方面的挑战。为使读者更好理解该领域最新进展，本文综述了基于非线性最小二乘和最小绝对误差的智能电网状态估计方法。为更好比较不同状态估计方法性能，首先描述了智能电网状态估计问题的克拉美罗下界。针对网络攻击问题，引入新的电力系统测量数据攻击模型，并介绍相应鲁棒状态估计方法。最后，分析配电网系统状态估计最新研究进展和挑战。仿真实验验证了该状态估计方法和理论的有效性和优点。

关键词：状态估计；克拉美罗下界；可行解追逐；半正定松弛；近线性算法；复合优化；网络攻击；坏数据检测

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无线信息与能量同时传输的鲁棒协作中继波束形成优化设计 None

Lu-lu ZHAO, Xing-long JIANG, Li-min LI, Guo-qiang ZENG, Hui-jie LIU

《信息与电子工程前沿（英文）》 2018年第19卷第11期页码 1432-1443 doi: 10.1631/FITEE.1601268

摘要：采用二分法和半定松弛法解决非鲁棒和鲁棒波束形成设计的非凸优化问题。由于半定松弛法的解不总是秩一的，提出一种迭代次梯度法求秩一解。

关键词：无线信息与能量同时传输；信道状态信息；鲁棒波束形成；半定松弛；迭代次梯度

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标题作者时间类型操作

时间—资源权衡协调问题的多目标优化决策模型

王先甲,万仲平

期刊论文