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Power system reconfiguration and loss minimization for a distribution systems using “Catfish PSO” algorithm

K Sathish KUMAR,S NAVEEN

《能源前沿（英文）》 2014年 第8卷 第4期   页码 434-442 doi: 10.1007/s11708-014-0313-y

摘要： One of the very important ways to save electrical energy in the distribution system is network reconfiguration for loss reduction. Distribution networks are built as interconnected mesh networks; however, they are arranged to be radial in operation. The distribution feeder reconfiguration is to find a radial operating structure that optimizes network performance while satisfying operating constraints. The change in network configuration is performed by opening sectionalizing (normally closed) and closing tie (normally opened) switches of the network. These switches are changed in such a way that the radial structure of networks is maintained, all of the loads are energized, power loss is reduced, power quality is enhanced, and system security is increased. Distribution feeder reconfiguration is a complex nonlinear combinatorial problem since the status of the switches is non-differentiable. This paper proposes a new evolutionary algorithm (EA) for solving the distribution feeder reconfiguration (DFR) problem for a 33-bus and a 16-bus sample network, which effectively ensures the loss minimization.

关键词： distribution system reconfiguration (DFR)     power loss reduction     catfish particle swarm optimization (catfish PSO)     radial structure    

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Calculation method of radial stress and deformation on conic threaded connections with interference fit

Shoujun CHEN, Qiang LI, Qi AN,

《机械工程前沿（英文）》 2010年 第5卷 第3期   页码 302-307 doi: 10.1007/s11465-010-0018-9

摘要： This paper presents a calculation method for radial stress distribution and deformation on conic threaded connections with interference fit. Based on elastic mechanics, a new calculation model is established using the thick-walled-cylindrical theory. A sample calculation for API 88.9 mm conic threaded connection indicates that the method proposed in this paper is reasonable, and the finite element analysis (FEA) method is used to validate the proposed method. The results obtained by the proposed method and FEA method are identical. The model offers a new way of calculating the radial stress and deformation on conic thread connections with interference fit.

关键词： conic threaded connections     interference fit     radial stress     deformation     finite element analysis (FEA)    

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Hierarchical ZSM-5 zeolite with radial mesopores: Preparation, formation mechanism and application for

Darui Wang, Hongmin Sun, Wei Liu, Zhenhao Shen, Weimin Yang

《化学科学与工程前沿（英文）》 2020年 第14卷 第2期   页码 248-257 doi: 10.1007/s11705-019-1853-9

摘要： Hierarchical ZSM-5 zeolite with radial mesopores is controllably synthesized using piperidine in a NaOH solution. The piperidine molecules enter the zeolite micropores and protect the zeolite framework from extensive desilication. The areas containing fewer aluminum atoms contain fewer piperidine protectant molecules and so they dissolve first. Small amounts of mesopores are then gradually generated in areas with more aluminum atoms and more piperidine protectant. In this manner, radial mesopores are formed in the ZSM-5 zeolite with a maximal preservation of the micropores and active sites. The optimal hierarchical ZSM-5 zeolite, prepared with a molar ratio of piperidine to zeolite of 0.03, had a mesopore surface area of 136 m ·g and a solid yield of 80%. The incorporation of the radial mesopores results in micropores that are interconnected which shortened the average diffusion path length. Compared to the parent zeolite, the hierarchical ZSM-5 zeolite possesses more accessible acid sites and has a higher catalytic activity and a longer lifetime for the alkylation of benzene.

关键词： hierarchical ZSM-5 zeolite     protective desilication     piperidine     radial mesopores     benzene alkylation    

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Different manipulation mode analysis of a radial symmetrical hexapod robot with leg–arm integration

《机械工程前沿（英文）》 2022年 第17卷 第1期   页码 8-8 doi: 10.1007/s11465-021-0664-0

摘要： With the widespread application of legged robot in various fields, the demand for a robot with high locomotion and manipulation ability is increasing. Adding an extra arm is a useful but general method for a legged robot to obtain manipulation ability. Hence, this paper proposes a novel hexapod robot with two integrated leg–arm limbs that obtain dexterous manipulation functions besides locomotion ability without adding an extra arm. The manipulation modes can be divided into coordinated manipulation condition and single-limb manipulation condition. The former condition mainly includes fixed coordinated clamping case and fixed coordinated shearing case. For the fixed coordinated clamping case, the degrees of freedom (DOFs) analysis of equivalent parallel mechanism by using screw theory and the constraint equation of two integrated limbs are established. For the fixed coordinated shearing case, the coordinated working space is determined, and an ideal coordinated manipulation ball is presented to guide the coordinated shearing task. In addition, the constraint analysis of two adjacent integrated limbs is performed. Then, mobile manipulation with one integrated leg–arm limb while using pentapod gait is discussed as the single-limb manipulation condition, including gait switching analysis between hexapod gait and pentapod gait, different pentapod gaits analysis, and a complex six-DOF manipulation while walking. Corresponding experiments are implemented, including clamping tasks with two integrated limbs, coordinated shearing task by using two integrated limbs, and mobile manipulation with pentapod gait. This robot provides a new approach to building a multifunctional locomotion platform.

关键词： leg–arm integration     hexapod robot     fixed coordinated manipulation     mobile manipulation    

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Comparison of optimal capacitor placement methods in radial distribution system with load growth and

Veera Venkata Satya Naryana MURTY, Ashwani KUMAR

《能源前沿（英文）》 2013年 第7卷 第2期   页码 197-213 doi: 10.1007/s11708-013-0249-7

摘要： In this paper, a combined power loss sensitivity (PLS) index-based approach is proposed to determine the optimal location of the capacitors in the radial distribution system (RDS) based on the real and reactive combined loss sensitivity index, as capacitor placement not only reduces real power loss with voltage profile improvement but also reduces reactive power loss due to the reactive power compensation in the network. The results have been obtained with the existing methods of power loss index (PLI) and index vector (IV) method for comparison. Besides, the optimal placement has been obtained with the proposed method as well as existing methods and the total kVar support has been obtained. In addition, the results of net cost savings for the 10-, 34-, and 69-bus systems are obtained for comparison. Moreover, the results have been obtained for a large system of 85 buses to validate the results with combined sensitivity based approach. Furthermore, the load growth factor has been considered in the study which is essential for the planning and expansion of the existing systems, whereas the impact of the realistic load model as ZIP load model has been considered for the study of all the systems.

关键词： load growth     load models     reactive power compensation     radial distribution system     power loss index (PLI)     power loss sensitivity (PLS)     index vector (IV)    

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A total torque index for dynamic performance evaluation of a radial symmetric six-legged robot

Kejia LI, Xilun DING, Marco CECCARELL

《机械工程前沿（英文）》 2012年 第7卷 第2期   页码 219-230 doi: 10.1007/s11465-012-0320-9

摘要：

This article focuses on the dynamic index and performance of a radial symmetric six-legged robot. At first the structure of the robot is described in brief and its inverse kinematics is presented. Then the dynamic model is formulated as based on the Lagrange equations. A novel index of total torque is proposed by considering the posture of the supporting legs. The new index can be used to optimize the leg’s structure and operation for consuming minimum power and avoiding unstable postures of the robot. A characterization of the proposed six-legged robot is obtained by a parametric analysis of robot performance through simulation using the presented dynamic model. Main influences are outlined as well as the usefulness of the proposed performance index.

关键词： six-legged robots     dynamic modeling     performance index    

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An efficient stochastic dynamic analysis of soil media using radial basis function artificial neural

P. ZAKIAN

《结构与土木工程前沿（英文）》 2017年 第11卷 第4期   页码 470-479 doi: 10.1007/s11709-017-0440-8

摘要： Since a lot of engineering problems are along with uncertain parameters, stochastic methods are of great importance for incorporating random nature of a system property or random nature of a system input. In this study, the stochastic dynamic analysis of soil mass is performed by finite element method in the frequency domain. Two methods are used for stochastic analysis of soil media which are spectral decomposition and Monte Carlo methods. Shear modulus of soil is considered as a random field and the seismic excitation is also imposed as a random process. In this research, artificial neural network is proposed and added to Monte Carlo method for sake of reducing computational effort of the random analysis. Then, the effects of the proposed artificial neural network are illustrated on decreasing computational time of Monte Carlo simulations in comparison with standard Monte Carlo and spectral decomposition methods. Numerical verifications are provided to indicate capabilities, accuracy and efficiency of the proposed strategy compared to the other techniques.

关键词： stochastic analysis     random seismic excitation     finite element method     artificial neural network     frequency domain analysis     Monte Carlo simulation    

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Radial electromagnetic type unbalance vibration self-recovery regulation system for high-end grinding

《机械工程前沿（英文）》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0763-1

摘要： Modern rotating machines, which are represented by high-end grinding machines, have developed toward high precision, intelligence, and high durability in recent years. As the core components of grinding machine spindles, grinding wheels greatly affect the vibration level during operation. The unbalance vibration self-recovery regulation (UVSRR) system is proposed to suppress the vibration of grinding wheels during workpiece processing, eliminating or minimizing the imbalance. First, technical principles and the system composition are introduced. Second, the balancing actuator in the UVSRR system is analyzed in detail. The advanced nature of the improved structure is presented through structure introduction and advantage analysis. The performance of the balancing actuator is mutually verified by the theoretical calculation of torque and software simulation. Results show that the self-locking torque satisfies the actual demand, and the driving torque is increased by 1.73 times compared with the traditional structure. Finally, the engineering application value of the UVSRR system is verified by laboratory performance comparison and actual factory application. The balancing speed and effect of the UVSRR system are better than those of an international mainstream product and, the quality of the workpieces machined in the factory improved by 40%.

关键词： UVSRR system     radial electromagnetic type     vibration suppression     performance simulation     engineering application    

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A redundantly actuated PRPRP radial mechanism in the segment erector of a shield machine for synchronization

Wanghui BU, Zhenyu LIU, Jianrong TAN, Jin CHENG

《机械工程前沿（英文）》 2011年 第6卷 第4期   页码 463-467 doi: 10.1007/s11465-011-0225-z

摘要：

The shield machine is a heavy construction machine for tunnel excavation, and the segment erector is an important subsystem of the shield machine. It is difficult to achieve precise control in the 6-DOF (degree of freedom) erector in the 2-DOF 5-bar radial mechanism. Hence, this paper proposes a redundantly actuated PRPRP radial mechanism for the segment erector. When the redundant actuator is unlocked, the radial mechanism is able to adjust its posture, which has two degrees of freedom. On the other hand, when the redundant actuator is locked or produces enough pre-tightening tensile force, the PRPRP mechanism can ensure the synchronization of the two driving hydraulic cylinders along the radial direction based on the mechanical structure, which has one degree of freedom. The redundant actuator also facilitates the equal application of two flexural torques at the hydraulic cylinders; thus, preventing the overload of a single cylinder.

关键词： redundant actuation     parallel mechanisms     five-bar mechanisms     segment erectors     shield machines    

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一种基于变异算子与淘汰重组机制的改进GWO及其应用 Article

Xiao-qing ZHANG, Zheng-feng MING

《信息与电子工程前沿（英文）》 2017年 第18卷 第11期   页码 1705-1719 doi: 10.1631/FITEE.1601555

摘要： 为了验证改进后算法的有效性，通过13个标准连续函数全局优化实验及RBF（radial basis function）网络逼近试验将MR-GWO算法与其它算法进行了比较，试验结果表明MR-GWO算法具有较强的竞争力

关键词： 群智能；苍狼优化算法；优化；RBF（radial basis function）网络    

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堆积床相变储热系统中径向孔隙率振荡分布对热性能的影响 Article

刘红兵, 赵长颖

《工程（英文）》 2021年 第7卷 第4期   页码 515-525 doi: 10.1016/j.eng.2020.05.020

摘要：

由于具有较高的储热能力和传热速率，堆积床相变储热被认为是一种很有潜力的储热方法。在堆积床中，壁面效应会影响相变胶囊的填充结构，从而引起径向孔隙率的振荡。本研究建立了一个基于球体实际堆积过程的三维堆积床相变储热模型，以描述径向孔隙率的振荡分布，并分析了其内部的流动和传热情况。通过在堆积床中沿径向不同位置截取圆柱面，揭示了相变胶囊的排列与径向孔隙率之间的对应关系。径向孔隙率的振荡分布导致换热流体速度呈不均匀分布，因此相变材料的径向温度分布和液相分数分布进一步受到影响。此外，本文讨论了不同的无量纲参数（如管与胶囊的直径比、雷诺数和史蒂芬数）对换热流体和相变材料径向特性的影响。结果表明，不同的直径比对应于不同的径向孔隙率分布。此外，随着直径比的增加，在壁面附近区域换热流体速度显著变化，而中心区域换热流体速度的不均匀性将减小。雷诺数和史蒂芬数对换热流体的相对速度分布有轻微影响，而更高的雷诺数可导致速度成比例地提高，史蒂芬数的增加可加快堆积床相变储热系统的储热过程。

关键词： 堆积床相变储热     径向孔隙率振荡     流动换热     传热强化     直径比    

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Radial porous SiO

Chuangnian Zhang, Ying Dong, Jing Gao, Xiaoli Wang, Yanjun Jiang

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1296-1311 doi: 10.1007/s11705-020-2034-6

摘要： Here, we reported a cancer nanovaccine based on SiO nanoflowers with a special radial pore structure, which greatly enhanced cross-presentation and induced the production of cytotoxic T lymphocyte cells secreting granzymes B and interferon- . The antigen ovalbumin was covalently conjugated onto the as-synthesized hierarchical SiO nanoflowers, and the adjuvant cytosine-phosphate-guanine was electrostatically adsorbed into their radial pore by simple mixing before use. The nanovaccine exhibited excellent storage stability without antigen release after 27 days of incubation, negligible cytotoxicity to dendritic cells, and a high antigen loading capacity of 430±66 mg·g support. Besides, the nanovaccine could be internalized by dendritic cells via multiple pathways. And the enhancement of antigen/adjuvant uptake and lysosome escape of antigen were observed. Noteworthy, culture of bone marrow-derived dendritic cells in the presence of nanovaccine proved the activation of dendritic cells and antigen cross-presentation as well as secretion of proinflammatory cytokines. Besides, study verified the targeting of nanovaccine to draining lymph nodes, the complete suppression of tumor in six out of ten mice, and the triggering of notable tumor growth delay. Overall, the present results indicated that the nanovaccine can be served as a potential therapeutic vaccine to treat cancer.

关键词： silica nanoflower     antigen delivery     cancer immunotherapy     nanovaccine    

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基于RBF神经网络的水文地质参数识别

张俊艳,魏连伟,韩文秀,邵景力,崔亚丽,张建立

《中国工程科学》 2004年 第6卷 第8期   页码 74-78

摘要：

水文地质参数识别问题是水文地质学上的一个难题。针对传统水文地质参数识别方法的局限性，提出了水文地质参数识别的径向基函数(RBF )神经网络方法，并通过算例验证了它的可行性与有效性，实现了水文地质参数的自动识别，提高了计算效率，比BP神经网络具有更好的参数识别效果。

关键词： 地下水     水文地质参数     径向基函数(RBF)神经网络     BP神经网络    

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Cannabidiol prevents depressive-like behaviors through the modulation of neural stem cell differentiation

《医学前沿（英文）》 2022年 第16卷 第2期   页码 227-239 doi: 10.1007/s11684-021-0896-8

摘要： Chronic stress impairs radial neural stem cell (rNSC) differentiation and adult hippocampal neurogenesis (AHN), whereas promoting AHN can increase stress resilience against depression. Therefore, investigating the mechanism of neural differentiation and AHN is of great importance for developing antidepressant drugs. The nonpsychoactive phytocannabinoid cannabidiol (CBD) has been shown to be effective against depression. However, whether CBD can modulate rNSC differentiation and hippocampal neurogenesis is unknown. Here, by using the chronic restraint stress (CRS) mouse model, we showed that hippocampal rNSCs mostly differentiated into astrocytes under stress conditions. Moreover, transcriptome analysis revealed that the FoxO signaling pathway was involved in the regulation of this process. The administration of CBD rescued depressive-like symptoms in CRS mice and prevented rNSCs overactivation and differentiation into astrocyte, which was partly mediated by the modulation of the FoxO signaling pathway. These results revealed a previously unknown neural mechanism for neural differentiation and AHN in depression and provided mechanistic insights into the antidepressive effects of CBD.

关键词： cannabidiol     depression     radial neural stem cells     neurogenesis    

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深厚表土层冻结壁厚度计算方法研究

沈慰安,王建州

《中国工程科学》 2011年 第13卷 第11期   页码 89-93

摘要：

针对冻结法凿井工程面临的表土层厚度不断增加，而现有冻结壁的设计理论滞后于工程实践的问题，目前冻结壁的设计和计算多数是将冻结壁视为均质和各向同性的厚壁圆筒，基于弹性和弹塑性理论进行计算的结果已经不能适用于未来深厚表土层的冻结法凿井工程，文章综述了冻结壁厚度设计理论的研究现状和存在的问题，并提出了考虑冻结壁径向非均匀的粘弹性分层计算模型，考虑径向非均质条件，井帮的径向变形较均质冻结壁小25 %~30 %，可以充分发挥冻结壁的承载和变形性能，有效减小冻结壁的厚度，具有一定的的工程应用价值。

关键词： 冻结壁     深厚表土层     分层计算模型     粘弹性    

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标题 作者 时间 类型 操作

Power system reconfiguration and loss minimization for a distribution systems using “Catfish PSO” algorithm

K Sathish KUMAR,S NAVEEN

期刊论文

Calculation method of radial stress and deformation on conic threaded connections with interference fit

Shoujun CHEN, Qiang LI, Qi AN,

期刊论文

Hierarchical ZSM-5 zeolite with radial mesopores: Preparation, formation mechanism and application for

Darui Wang, Hongmin Sun, Wei Liu, Zhenhao Shen, Weimin Yang

期刊论文

Different manipulation mode analysis of a radial symmetrical hexapod robot with leg–arm integration

期刊论文

Comparison of optimal capacitor placement methods in radial distribution system with load growth and

Veera Venkata Satya Naryana MURTY, Ashwani KUMAR

期刊论文

A total torque index for dynamic performance evaluation of a radial symmetric six-legged robot

Kejia LI, Xilun DING, Marco CECCARELL

期刊论文

An efficient stochastic dynamic analysis of soil media using radial basis function artificial neural

P. ZAKIAN

期刊论文

Radial electromagnetic type unbalance vibration self-recovery regulation system for high-end grinding

期刊论文

A redundantly actuated PRPRP radial mechanism in the segment erector of a shield machine for synchronization

Wanghui BU, Zhenyu LIU, Jianrong TAN, Jin CHENG

期刊论文

一种基于变异算子与淘汰重组机制的改进GWO及其应用

Xiao-qing ZHANG, Zheng-feng MING

期刊论文

堆积床相变储热系统中径向孔隙率振荡分布对热性能的影响

刘红兵, 赵长颖

期刊论文

Radial porous SiO

Chuangnian Zhang, Ying Dong, Jing Gao, Xiaoli Wang, Yanjun Jiang

期刊论文

基于RBF神经网络的水文地质参数识别

张俊艳,魏连伟,韩文秀,邵景力,崔亚丽,张建立

期刊论文

Cannabidiol prevents depressive-like behaviors through the modulation of neural stem cell differentiation

期刊论文

深厚表土层冻结壁厚度计算方法研究

沈慰安,王建州

期刊论文