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期刊论文 48

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Lagrange方程 1

二阶矩技术 1

云模型 1

任意分布参数 1

优化设计 1

倒排索引;索引遍历;查询延迟;最大重要度优先查询;动态剪枝 1

倒立摆 1

倾角传感器 1

冷空气路径 1

力矩反馈器 1

加速度计 1

动力学 1

医院中子照射器 1

厚度控制 1

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Sagittal SLIP-anchored task space control for a monopode robot traversing irregular terrain

Haitao YU, Haibo GAO, Liang DING, Zongquan DENG

《机械工程前沿(英文)》 2020年 第15卷 第2期   页码 193-208 doi: 10.1007/s11465-019-0569-3

摘要: As a well-explored template that captures the essential dynamical behaviors of legged locomotion on sagittal plane, the spring-loaded inverted pendulum (SLIP) model has been extensively employed in both biomechanical study and robotics research. Aiming at fully leveraging the merits of the SLIP model to generate the adaptive trajectories of the center of mass (CoM) with maneuverability, this study presents a novel two-layered sagittal SLIP-anchored (SSA) task space control for a monopode robot to deal with terrain irregularity. This work begins with an analytical investigation of sagittal SLIP dynamics by deriving an approximate solution with satisfactory apex prediction accuracy, and a two-layered SSA task space controller is subsequently developed for the monopode robot. The higher layer employs an analytical approximate representation of the sagittal SLIP model to form a deadbeat controller, which generates an adaptive reference trajectory for the CoM. The lower layer enforces the monopode robot to reproduce a generated CoM movement by using a task space controller to transfer the reference CoM commands into joint torques of the multi-degree of freedom monopode robot. Consequently, an adaptive hopping behavior is exhibited by the robot when traversing irregular terrain. Simulation results have demonstrated the effectiveness of the proposed method.

关键词: legged robots     spring-loaded inverted pendulum     task space control     apex return map     deadbeat control     irregular terrain negotiation    

三级倒立摆的云控制方法及动平衡模式

李德毅

《中国工程科学》 1999年 第1卷 第2期   页码 41-46

摘要:

文章提出了定性和定量之间转换的云模型的形式化表示方法,用来反映语言值中蕴涵的模糊性和随机性,给出云发生器的生成算法,解释多条定性推理规则同时被激活时的不确定性推理机制。利用这种智能控制方法有效地实现了单电机控制的一、二、三级倒立摆的多种不同动平衡姿态,显示其鲁棒性,并给出了详细试验结果。研究成果不仅可用于对太空飞行器以及机器人控制,而且对揭示定性定量转换规律和策略具有普遍意义。

关键词: 智能控制     云模型     定性推理     倒立摆    

基于Lagrange方程建模的单级旋转倒立摆控制

吴爱国,张小明,张钊

《中国工程科学》 2005年 第7卷 第10期   页码 11-15

摘要:

介绍一种新型单级旋转倒立摆系统的构成,通过对其动力学特性的分析建立了基于Lagrange方程的数学模型。在平衡点附近给出系统的线性化模型,对系统的稳定性、能控性和能观性进行了分析。利用线性二次型最优控制策略LQR方法设计了控制器,并在仿真实验和实物实验中实现了倒立摆的平衡控制。实验表明,系统稳定性好、鲁棒性较强。

关键词: 旋转倒立摆     Lagrange方程     最优控制策略LQR    

PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

《环境科学与工程前沿(英文)》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1369-z

摘要:

• Pt/CZL exhibits the optimum catalytic performance for HC and NOx elimination.

关键词: Precious metal-loaded (Ce     Zr     La)O2 catalysts     Oxygen mobility     Catalytic performance    

Finite element analysis and structural design of pretensioned inverted T-beams with web openings

Hock Tian CHENG, Bashar S. MOHAMMED, Kamal Nasharuddin MUSTAPHA

《结构与土木工程前沿(英文)》 2009年 第3卷 第2期   页码 148-157 doi: 10.1007/s11709-009-0030-5

摘要: This paper presents the results of a research project aimed at providing standard circular web openings to the popular precast pretensioned inverted T-beam. Opening size and placement and required materials strengths were investigated. In this paper the nonlinear analysis and design of simply supported pretensioned inverted T-beam with circular web openings are presented. Two design parameters are varied: opening location and number of openings. The results from nonlinear finite element analysis were substantiated by test results from five pretensioned inverted T-beams with web opening and one solid beam. Good agreement is shown between the theoretical and the experimental results. The test results obtained from this investigation show that the performance of the specimens with web openings is almost identical to that of the specimen without web openings. A simple design method for pretensioned inverted T-beam with circular web openings is proposed.

关键词: prestressed concrete     inverted-T beam     web opening    

The cavitation erosion damage process of dynamically loaded journal bearings

MA Yan-yan, CHENG Xian-hua

《机械工程前沿(英文)》 2006年 第1卷 第4期   页码 461-464 doi: 10.1007/s11465-006-0059-2

摘要: The cavitation damage model was built using finite element analysis software MSC.Marc. This paper attempted to numerically analyze the action process based on damage mechanics when a jet created by bubble collapse acted on the bearing surface in the process of cavitation erosion. The numerical results show that the values of equivalent plastic strain and void volume fraction increase with time. The values of damage scalar are higher on the bearing surface and subsurface, and decrease when it approaches the interface of overlay and nickel layer. The strain history and damage evolvement of bearing material acted on by jet impact load can be calculated efficiently using the proposed method, which develops a new method of analyzing cavitation erosion failure of the bearing surface.

关键词: bearing     fraction increase     collapse     process     evolvement    

Analysis and characterization of wind-solar-constant torque spring hybridized model

Shantanu ACHARYA,Subhadeep BHATTACHARJEE

《能源前沿(英文)》 2014年 第8卷 第3期   页码 279-289 doi: 10.1007/s11708-014-0312-z

摘要: Solar and wind are the most promising renewable energy resources. But their unpredictable and varying nature prevents them from being used as the sole resource for power generation. This paper presents a model of wind and solar thermal hybrid power plant with a spring storage system which is expected to play an efficient role in combating with the drawbacks related to renewable power generation. In the proposed scheme, wind energy is harnessed by a hybrid vertical axis wind turbine, solar energy is utilized by a Stirling engine, and the surplus energy is stored in a winding spring. The paper discusses the working methodologies and analyses the performance of such 2.6 kW hybrid power plant model. It has been observed that the plant is capable of consistently generating 50% of its rated capacity irrespective of limitations in solar and wind resources.

关键词: hybrid vertical axis wind turbine     Stirling engine     solar-thermal energy     wind energy     constant torque spring    

Preparation of a Pb loaded gas diffusion electrode and its application to CO

Ang LI, Hua WANG, Jinyu HAN, Li LIU

《化学科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 381-388 doi: 10.1007/s11705-012-1216-2

摘要: A Pb loaded gas diffusion electrode was fabricated and used for the electroreduction of CO to formic acid. The Pb/C catalyst was prepared by isometric impregnation. The crystal structure and morphology of the Pb/C catalyst were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). The preparation conditions of the gas diffusion electrode were optimized by adjusting the amounts of polytetrafluoroethylene (PTFE) in the gas diffusion layer and acetylene black in the catalytic layer. The electrochemical performance of the as-prepared gas diffusion electrode was studied by chronoamperometry and cyclic voltammetry. The optimized gas diffusion electrode showed good catalytic performance for the electroreduction of CO . The current efficiency of formic acid after 1 h of operation reached a maximum of 22% at -2.0 V versus saturated calomel electrode (SCE).

关键词: electroreduction     carbon dioxide     lead catalyst     gas diffusion electrode     formic acid    

Selective targeted adsorption and inactivation of antibiotic-resistant bacteria by Cr-loaded mixed metal

《环境科学与工程前沿(英文)》 2022年 第16卷 第6期 doi: 10.1007/s11783-021-1502-7

摘要:

• LDHs and MMOs was synthesized by ultrasound-assisted one-step co-precipitation.

关键词: Heavy metal adsorption     Magnetic hydrotalcite     ARBs removal     Cr(VI)-MMOs combined antibacterial activity    

Back to the spring of Wuhan: facts and hope of COVID-19 outbreak

Guangbiao Zhou, Saijuan Chen, Zhu Chen

《医学前沿(英文)》 2020年 第14卷 第2期   页码 113-116 doi: 10.1007/s11684-020-0758-9

Ultimate load analysis of pretensioned inverted T-beams with circular web openings

Hock Tian CHENG , Bashar S. MOHAMMED , Kamal Nasharuddin MUSTAPHA ,

《结构与土木工程前沿(英文)》 2009年 第3卷 第3期   页码 262-271 doi: 10.1007/s11709-009-0031-4

摘要: The provision of transverse openings in floor beams to facilitate the passage of utility pipes and service ducts not only results in a more systematic layout of pipes and ducts, it also translates into substantial economic savings in the construction of a multi-storey building. In this paper, ultimate load analysis of statically loaded simply supported pretensioned inverted T-beams with circular web openings is presented. Major findings relevant to ultimate load analysis of pretensioned beams with circular web openings are summarized. An attempt has been made to answer the frequently asked questions related to ultimate load analysis on multiple circular web openings. It has been shown that the analysis method for pretensioned beams with multiple large circular web openings can be further simplified without sacrificing rationality.

关键词: pretensioned inverted T-beam     web opening    

Metal-organic framework loaded manganese oxides as efficient catalysts for low-temperature selective

Minhua Zhang, Baojuan Huang, Haoxi Jiang, Yifei Chen

《化学科学与工程前沿(英文)》 2017年 第11卷 第4期   页码 594-602 doi: 10.1007/s11705-017-1668-5

摘要: A mild deposition method was used to fabricate Mn-based catalysts on a UiO-66 carrier for the selective catalytic reduction of NO by NH (NH -SCR). The catalyst with 8.5 wt-% MnO loading had the highest catalytic activity for NH -SCR with a wide temperature window (100–290 °C) for 90% NO conversion. Characterization of the prepared MnO /UiO-66 catalysts showed that the catalysts had the crystal structure and porosity of the UiO-66 carrier and that the manganese particles were well-distributed on the surface of the catalyst. X-ray photoelectron spectroscopy analysis showed that there are strong interactions between the MnO and the Zr oxide secondary building units of the UiO-66 which has a positive effect on the catalytic activity. The 8.5 wt-% MnO catalyst maintained excellent activity during a 24-h stability test and exhibited good resistance to SO poisoning.

关键词: metal-organic framework     selective catalytic reduction     manganese oxides     deNOx     SO2 resistance    

Static balancing of planar articulated robots

Giuseppe QUAGLIA,Zhe YIN

《机械工程前沿(英文)》 2015年 第10卷 第4期   页码 326-343 doi: 10.1007/s11465-015-0355-9

摘要:

Static balancing for a manipulator’s weight is necessary in terms of energy saving and performance improvement. This paper proposes a method to design balancing devices for articulated robots in industry, based on robotic dynamics. Full design details for the balancing system using springs are presented from two aspects: One is the optimization for the position of the balancing system; the other is the design of the spring parameters. As examples, two feasible balancing devices are proposed, based on different robotic structures: The first solution consists of linkages and springs; the other consists of pulleys, cross mechanisms and (hydro-) pneumatic springs. Then the two solutions are compared. Pneumatic, hydro-pneumatic and mechanical springs are discussed and their parameters are decided according to the requirements of torque compensation. Numerical results show that with the proper design using the methodology presented in this paper, an articulated robot can be statically balanced perfectly in all configurations. This paper therefore provides a design method of the balancing system for other similar structures.

关键词: robotics     static balancing     pneumatic spring     mechanical spring     torque compensation    

A perspective of “Nuclear Hot Spring” for long-term sustainable economy of the world

Yingzhong LU

《能源前沿(英文)》 2011年 第5卷 第4期   页码 349-357 doi: 10.1007/s11708-011-0168-4

摘要: The rapid growth of human economy in the late 20th century gave rise to great concern over sustainability of the world. A pessimistic “Full World Model” forecasts that human economy could not develop further. The nuclear fission (and fusion later), however, could release huge amount of energy to create sufficient useful material resources and turn the said pessimistic modelinto a new optimistic “Sustainable World Model”.The dilemma of nuclear energy (Military Giant vs. Civil Dwarf) jeopardizes its performance as a “Technologic Fixer”. According to Mother Nature’s teachings, the elimination of the root-causes of the design-based risk factors could solve this problem. Recent technology break-through from inherent safety to natural safety has been made in China. The proposed full-power natural circulation “Nuclear Hot Spring (NHS)” reactor could operate solely on natural forces without complex man-made coolant circulation equipment and human-operated control systems. The cheap, unlimited supply of energy from nuclear energy could change the geopolitics forever, and finally eliminate the root-causes of most international and regional conflicts.

关键词: natural safety reactor     full power natural circulation     sustainable world economy    

Inverted duplication including

Ming TIAN,Suyun FANG,Yanqiang WANG,Xiaorong GU,Chungang FENG,Rui HAO,Xiaoxiang HU,Ning LI

《农业科学与工程前沿(英文)》 2014年 第1卷 第2期   页码 121-129 doi: 10.15302/J-FASE-2014026

摘要: The dermal hyperpigmentation phenotype in chickens is controlled by the dominant fibromelanosis allele. One of the ten unique characteristics of Silkie chickens is the fibromelanosis phenotype, which is pigmentation in the dermal layer of the skin and connective tissue. In this study, we found a mutation of fibromelanosis, a genomic rearrangement that included an inverted duplication of ( ), is responsible. We show that, as a stimulator of melanoblast proliferation, expression was increased in silkie embryos and in both skin and muscle throughout adulthood. expression led to an increase in expression of the downstream genes and and was closely relate with the hyperpigmentation phenotype. We examined eight different Chinese chicken breeds showing hyperpigmentation and conclude that this structural genetic variant exists in all fibromelanosis chicken breeds.

关键词: dermal hyperpigmentation     duplication     endothelin 3     Silkie chicken    

标题 作者 时间 类型 操作

Sagittal SLIP-anchored task space control for a monopode robot traversing irregular terrain

Haitao YU, Haibo GAO, Liang DING, Zongquan DENG

期刊论文

三级倒立摆的云控制方法及动平衡模式

李德毅

期刊论文

基于Lagrange方程建模的单级旋转倒立摆控制

吴爱国,张小明,张钊

期刊论文

PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

期刊论文

Finite element analysis and structural design of pretensioned inverted T-beams with web openings

Hock Tian CHENG, Bashar S. MOHAMMED, Kamal Nasharuddin MUSTAPHA

期刊论文

The cavitation erosion damage process of dynamically loaded journal bearings

MA Yan-yan, CHENG Xian-hua

期刊论文

Analysis and characterization of wind-solar-constant torque spring hybridized model

Shantanu ACHARYA,Subhadeep BHATTACHARJEE

期刊论文

Preparation of a Pb loaded gas diffusion electrode and its application to CO

Ang LI, Hua WANG, Jinyu HAN, Li LIU

期刊论文

Selective targeted adsorption and inactivation of antibiotic-resistant bacteria by Cr-loaded mixed metal

期刊论文

Back to the spring of Wuhan: facts and hope of COVID-19 outbreak

Guangbiao Zhou, Saijuan Chen, Zhu Chen

期刊论文

Ultimate load analysis of pretensioned inverted T-beams with circular web openings

Hock Tian CHENG , Bashar S. MOHAMMED , Kamal Nasharuddin MUSTAPHA ,

期刊论文

Metal-organic framework loaded manganese oxides as efficient catalysts for low-temperature selective

Minhua Zhang, Baojuan Huang, Haoxi Jiang, Yifei Chen

期刊论文

Static balancing of planar articulated robots

Giuseppe QUAGLIA,Zhe YIN

期刊论文

A perspective of “Nuclear Hot Spring” for long-term sustainable economy of the world

Yingzhong LU

期刊论文

Inverted duplication including

Ming TIAN,Suyun FANG,Yanqiang WANG,Xiaorong GU,Chungang FENG,Rui HAO,Xiaoxiang HU,Ning LI

期刊论文