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Multi-objective optimization in a finite time thermodynamic method for dish-Stirling by branch and boundmethod and MOPSO algorithm

Mohammad Reza NAZEMZADEGAN, Alibakhsh KASAEIAN, Somayeh TOGHYANI, Mohammad Hossein AHMADI, R. SAIDUR, Tingzhen MING

《能源前沿（英文）》 2020年 第14卷 第3期   页码 649-665 doi: 10.1007/s11708-018-0548-0

摘要： There are various analyses for a solar system with the dish-Stirling technology. One of those analyses is the finite time thermodynamic analysis by which the total power of the system can be obtained by calculating the process time. In this study, the convection and radiation heat transfer losses from collector surface, the conduction heat transfer between hot and cold cylinders, and cold side heat exchanger have been considered. During this investigation, four objective functions have been optimized simultaneously, including power, efficiency, entropy, and economic factors. In addition to the four-objective optimization, three-objective, two-objective, and single-objective optimizations have been done on the dish-Stirling model. The algorithm of multi-objective particle swarm optimization (MOPSO) with post-expression of preferences is used for multi-objective optimizations while the branch and bound algorithm with pre-expression of preferences is used for single-objective and multi-objective optimizations. In the case of multi-objective optimizations with post-expression of preferences, Pareto optimal front are obtained, afterward by implementing the fuzzy, LINMAP, and TOPSIS decision making algorithms, the single optimum results can be achieved. The comparison of the results shows the benefits of MOPSO in optimizing dish Stirling finite time thermodynamic equations.

关键词： dish-Stirling     finite time model     branch and bound algorithm     multi-objective particle swarm optimization (MOPSO)    

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Supplier selection and order splitting in multiple-sourcing inventory systems

WANG Guicong, JIANG Zhaoliang, LI Zhaoqian, LIU Wenping

《机械工程前沿（英文）》 2008年 第3卷 第1期   页码 23-27 doi: 10.1007/s11465-008-0016-3

摘要： Supplier selection and inventory control are critical decision processes in single-item multiple-supplier systems. An integer linear programming model is proposed to help managers determine the reorder level, choose the best suppliers, and place the optimum order quantities so that the total average inventory cost is minimum, and constraints of supplier ability, quality, and demand are considered. An algorithm combining the branch-bound algorithm and enumeration algorithm is developed to solve the problems. Application of the proposed model in an automobile industry shows that it is effective.

关键词： automobile industry     branch-bound algorithm     selection     single-item multiple-supplier     effective    

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Branch-pipe-routing approach for ships using improved genetic algorithm

Haiteng SUI,Wentie NIU

《机械工程前沿（英文）》 2016年 第11卷 第3期   页码 316-323 doi: 10.1007/s11465-016-0384-z

摘要：

Branch-pipe routing plays fundamental and critical roles in ship-pipe design. The branch-pipe-routing problem is a complex combinatorial optimization problem and is thus difficult to solve when depending only on human experts. A modified genetic-algorithm-based approach is proposed in this paper to solve this problem. The simplified layout space is first divided into three-dimensional (3D) grids to build its mathematical model. Branch pipes in layout space are regarded as a combination of several two-point pipes, and the pipe route between two connection points is generated using an improved maze algorithm. The coding of branch pipes is then defined, and the genetic operators are devised, especially the complete crossover strategy that greatly accelerates the convergence speed. Finally, simulation tests demonstrate the performance of proposed method.

关键词： branch pipe     ship industry     piping system     optimization algorithm    

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Effects of environmental factors on the production and release of matrix-bound phosphine from lake sediments

GENG Jinju, WANG Qiang, WANG Xiaorong, NIU Xiaojun

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 120-124 doi: 10.1007/s11783-007-0022-4

摘要： Effects of pH, temperature, and oxygen on the production and release of phosphine in eutrophic lake sediments were investigated under laboratory tests. Results indicated that the elimination of matrix-bound phosphine was accelerated under initial pH 1 or 12. Phosphine levels could reach maximum under initial pH 10. The contents of phosphine increased with the addition of alkali under pH 4 12. The rates of phosphine production and release from lake sediments varied with temperature. 20?C was the most favorable temperature for the production of matrix-bound phosphine. Oxygen showed little effect on matrix-bound phosphine. Matrix-bound phosphine concentrations in lake sediments were concluded to be dependent on a balance of natural generation and depletion processes.
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Upper bound solution to seismic active earth pressure of submerged backfill subjected to partial drainage

《结构与土木工程前沿（英文）》 2021年 第15卷 第6期   页码 1480-1493 doi: 10.1007/s11709-021-0776-y

摘要： In waterfront geotechnical engineering, seismic and drainage conditions must be considered in the design of retaining structures. This paper proposes a general analytical method to evaluate the seismic active earth pressure on a retaining wall with backfill subjected to partial steady seepage flow under seismic conditions. The method comprises the following steps: i) determination of the total head, ii) upper bound solution of seismic active earth thrust, and iii) deduction for the earth pressure distribution. The determination of total head h(x,z) relies on the Fourier series expansions, and the expressions of the seismic active earth thrust and pressure are derived by using the upper bound theorem. Parametric studies reveal that insufficient drainage and earthquakes are crucial factors that cause unfavorable earth pressure. The numerical results confirm the validity of the total head distribution. Comparisons indicate that the proposed method is consistent with other relevant existing methods in terms of predicting seismic active earth pressure. The method can be applied to the seismic design of waterfront retaining walls.

关键词： seismic active earth pressure     partial seepage flow     pore pressure     anisotropy     upper bound theorem    

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Effect of undercut on the lower bound stability of vertical rock escarpment using finite element and

Shuvankar DAS; Debarghya CHAKRABORTY

《结构与土木工程前沿（英文）》 2022年 第16卷 第8期   页码 1040-1055 doi: 10.1007/s11709-022-0841-1

摘要： In the present study, the stability of a vertical rock escarpment is determined by considering the influence of undercut. Lower bound finite element limit analysis in association with Power Cone Programming (PCP) is applied to incorporate the failure of rock mass with the help of the Generalized Hoek-Brown yield criterion. The change in stability due to the presence of undercut is expressed in terms of a non-dimensional stability number (σci/γH). The variations of the magnitude of σci/γH are presented as design charts by considering the different magnitudes of undercut offset (H/vu and wu/vu) from the vertical edge and different magnitudes of Hoek-Brown rock mass strength parameters (Geological Strength Index (GSI), rock parameter (mi,), Disturbance factor (D)). The obtained results indicate that undercut can cause a severe stability problem in rock mass having poor strength. With the help of regression analysis of the computed results, a simplified design equation is proposed for obtaining σci/γH. By performing sensitivity analysis for an undisturbed vertical rock escarpment, we have found that the undercut height ratio (H/vu) is the most sensitive parameter followed by GSI, undercut shape ratio (wu/vu), and mi. The developed design equation as well as design charts can be useful for practicing engineers to determine the stability of the vertical rock escarpment in the presence of undercut. Failure patterns are also presented to understand type of failure and extent of plastic state during collapse.

关键词： undercut     vertical escarpment     stability     Hoek-Brown yield criterion     PCP    

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Particle-bound polycyclic aromatic hydrocarbons in typical urban of Yunnan-Guizhou Plateau: Characterization

《环境科学与工程前沿（英文）》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1535-6

摘要：

• The sampling was conducted in city on the Yunnan-Guizhou Plateau for one year.

关键词： Particle-associated PAHs     Fine particle     Source appointment     Group analysis     Risk assessment     Biomass burning    

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Correction to: Effect of undercut on the lower bound stability of vertical rock escarpment using finite

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0035-5

摘要： Correction to: Effect of undercut on the lower bound stability of vertical rock escarpment using finite element and power cone programming

关键词： finite element power     stability rock escarpment    

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Bearing and uplift capacities of under-reamed piles in soft clay underlaid by stiff clay using lower-bound

Mantu MAJUMDER, Debarghya CHAKRABORTY

《结构与土木工程前沿（英文）》 2021年 第15卷 第2期   页码 537-551 doi: 10.1007/s11709-021-0708-x

摘要： Ensuring a safe foundation design in soft clay is always a challenging task to engineers. In the present study, the effectiveness of under-reamed piles in soft clay underlaid by stiff clay is numerically studied using the lower-bound finite element limit analysis (LB FELA). The bearing and uplift capacities of under-reamed piles are estimated through non-dimensional factors and , respectively. These factors increased remarkably and marginally compared to and of the piles without bulbs when the bulb is placed in stiff and soft clay, respectively. For a given ratio of undrained cohesion of stiff to soft clay ( / ), the factors and moderately increased with the increase in the length-to-shaft-diameter ratio ( / ) and adhesion factors in soft clay ( ) and stiff clay ( ). The variation of radial stress along the pile–soil interface, distribution of axial force in the under-reamed piles, and state of plastic shear failure in the soil are also studied under axial compression and tension. The results of this study are expected to be useful for the estimation of the bearing and uplift capacities of under-reamed piles in uniform clay and soft clay underlaid by stiff clay.

关键词： bearing capacity     uplift capacity     under-reamed pile     clay     limit analysis    

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双枝模糊决策与决策识别问题

史开泉,李歧强

《中国工程科学》 2001年 第3卷 第1期   页码 71-77

摘要：

文章提出具有中性域X*(X*≠{x})X的上的双枝模糊决策的概念和决策优化分析模型、决策判定定理、决策识别定理、决策去余定理和决策因素域X上的挖洞原理。双枝模糊决策具有下列特征：决策结论的双向依赖特性，决策结论的叠加合成特性，决策结论的枝-分离特性，决策结论的枝-退化特性，决策结论的非失误特性。研究结果得到了应用。

关键词： 双枝模糊决策     决策模型     决策判定定理     决策识别定理     决策去余定理     挖洞原理    

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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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基于非关联流动法则的滑移线场及上限法研究

郑颖人,邓楚键,王敬林

《中国工程科学》 2010年 第12卷 第8期   页码 56-69

摘要：

当前岩土材料的滑移线场理论及上限法中都广泛采用经典塑性理论中的关联流动法则，由此得出应力特征线与速度滑移线一致的结论。而试验得知，岩土材料并不服从关联流动法则，因而应力特征线与速度滑移线不可能重合。文章分析了基于关联流动法则的滑移线场及上限法中存在的问题，根据广义塑性理论推导了基于非关联流动法则的滑移线场及上限法，消除了现行滑移线场理论及上限法理论中的种种矛盾。

关键词： 滑移线场     上限法     关联流动法则     非关联流动法则     广义塑性理论    

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Modeling limit force capacities of high force to volume lead extrusion dampers

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 609-622 doi: 10.1007/s11709-021-0724-x

摘要： Lead extrusion dampers are supplemental energy-dissipation devices that are used to mitigate seismic structural damage. Small volumetric sizes and high force capacities define high-force-to-volume (HF2V) devices, which can absorb significant response energy without sacrificial damage. However, the design of such devices for specific force capacities has proven difficult based on the complexities of their internal reaction mechanisms, leading to the adoption of empirical approaches. This study developed upper- and lower-bound force capacity estimates from analytical mechanics based on direct and indirect metal extrusion for guiding design. The derived equations are strictly functions of HF2V device geometric parameters, lead material properties, and extrusion mechanics. The upper-bound estimates from direct and indirect extrusion are denoted as (FUB,1, FUB,2) and (FUB,3, FUB,4), respectively, and the lower-bound estimates are denoted as (FLB, FLB,1) based on the combination of extrusion and friction forces. The proposed models were validated by comparing the predicted bounds to experimental force capacity data from 15 experimental HF2V device tests. The experimental device forces all lie above the lower-bound estimates (FLB, FLB,1) and below the upper-bound estimates (FUB,1, FUB,2, FUB,4). Overall, the (FLB, FUB,2) pair provides wider bounds and the (FLB,1, FUB,4/FUB,1) pair provides narrower bounds. The (FLB,1, FUB,1) pair has a mean lower-bound gap of 36%, meaning the lower bound was 74% of the actual device force on average. The mean upper-bound gap was 33%. The bulge area and cylinder diameter of HF2V devices are key parameters affecting device forces. These relatively tight bounds provide useful mechanics-based predictive design guides for ensuring that device forces are within the targeted design range after manufacturing.

关键词： extrusion     lead dampers     upper and lower bound     analytical modelling     limit force    

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Controlling interstory drift ratio profiles via topology optimization strategies

《结构与土木工程前沿（英文）》 2023年 第17卷 第2期   页码 165-178 doi: 10.1007/s11709-022-0892-3

摘要： An approach to control the profiles of interstory drift ratios along the height of building structures via topology optimization is proposed herein. The theoretical foundation of the proposed approach involves solving a min–max optimization problem to suppress the maximum interstory drift ratio among all stories. Two formulations are suggested: one inherits the bound formulation and the other utilizes a p-norm function to aggregate all individual interstory drift ratios. The proposed methodology can shape the interstory drift ratio profiles into inverted triangular or quadratic patterns because it realizes profile control using a group of shape weight coefficients. The proposed formulations are validated via a series of numerical examples. The disparity between the two formulations is clear. The optimization results show the optimal structural features for controlling the interstory drift ratios under different requirements.

关键词： interstory drift ratio     aggregation function     bound formulation     min–max problem     topology optimization    

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具有双支路交错拓扑结构和轻载效率优化模式的大电流、高集成度开关电容分压器 Research Articles

刘胜1,赵梦恋2,杨朝2,吴皓楠2,吴晓波1

《信息与电子工程前沿（英文）》 2022年 第23卷 第2期   页码 317-327 doi: 10.1631/FITEE.2000404

摘要： 由于无磁且容易实现高集成度，开关电容（SC）变换器作为一种直流变压器在现代电子领域具有广泛应用前景。然而，设计具有大电流和高功率的SC变换器仍面临挑战。本文提出一种双支路SC分压器拓扑，并通过集成电路（IC）得以实现。所设计SC变换器能驱动大电流负载，将其使用范围扩展至大功率应用场合。该SC变换器具有1/2的恒定变换比，其双支路交错操作方式可确保输入电流的连续性。此外，提出一种使用电容耦合型浮动电压电平转换器的片上栅极驱动方法有效驱动全NMOS功率链。通过自供电结构，飞电容器本身也是用于栅极驱动的自举电容器，从而减少所需元器件数量。采用数字调制方式，在轻载时自动降低开关频率以提高效率。所设计SC变换器IC使用180 nm三阱BCD工艺制造。实验结果证明了所提双支路交错操作方式和自供电栅极驱动方法的有效性。所设计SC变换器可在5至12 V的输入电压下驱动高达4 A的负载电流，功率效率高达96.5％。在轻负载条件下，使用所提优化方法，电源效率提高了30％。

关键词： 开关电容变换器；双支路；集成电路；自举栅极驱动器    

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标题 作者 时间 类型 操作

Multi-objective optimization in a finite time thermodynamic method for dish-Stirling by branch and boundmethod and MOPSO algorithm

Mohammad Reza NAZEMZADEGAN, Alibakhsh KASAEIAN, Somayeh TOGHYANI, Mohammad Hossein AHMADI, R. SAIDUR, Tingzhen MING

期刊论文

Supplier selection and order splitting in multiple-sourcing inventory systems

WANG Guicong, JIANG Zhaoliang, LI Zhaoqian, LIU Wenping

期刊论文

Branch-pipe-routing approach for ships using improved genetic algorithm

Haiteng SUI,Wentie NIU

期刊论文

Effects of environmental factors on the production and release of matrix-bound phosphine from lake sediments

GENG Jinju, WANG Qiang, WANG Xiaorong, NIU Xiaojun

期刊论文

Upper bound solution to seismic active earth pressure of submerged backfill subjected to partial drainage

期刊论文

Effect of undercut on the lower bound stability of vertical rock escarpment using finite element and

Shuvankar DAS; Debarghya CHAKRABORTY

期刊论文

Particle-bound polycyclic aromatic hydrocarbons in typical urban of Yunnan-Guizhou Plateau: Characterization

期刊论文

Correction to: Effect of undercut on the lower bound stability of vertical rock escarpment using finite

期刊论文

Bearing and uplift capacities of under-reamed piles in soft clay underlaid by stiff clay using lower-bound

Mantu MAJUMDER, Debarghya CHAKRABORTY

期刊论文

双枝模糊决策与决策识别问题

史开泉,李歧强

期刊论文

智能电网状态估计方法最新进展综述

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

期刊论文

基于非关联流动法则的滑移线场及上限法研究

郑颖人,邓楚键,王敬林

期刊论文

Modeling limit force capacities of high force to volume lead extrusion dampers

期刊论文

Controlling interstory drift ratio profiles via topology optimization strategies

期刊论文

具有双支路交错拓扑结构和轻载效率优化模式的大电流、高集成度开关电容分压器

刘胜1,赵梦恋2,杨朝2,吴皓楠2,吴晓波1

期刊论文