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Trajectory planning and base attitude restoration of dual-arm free-floating space robot by enhanced bidirectional

Zongwu XIE1 , Xiaoyu ZHAO1 , Zainan JIANG1 , Haitao YANG2 , Chongyang LI1

《机械工程前沿（英文）》 2022年 第17卷 第1期 doi: 10.1007/s11465-021-0658-y

摘要： When free-floating space robots perform space tasks, the satellite base attitude is disturbed by the dynamic coupling. The disturbance of the base orientation may affect the communication between the space robot and the control center on earth. In this paper, the enhanced bidirectional approach is proposed to plan the manipulator trajectory and eliminate the final base attitude variation. A novel acceleration level state equation for the nonholonomic problem is proposed, and a new intermediate variable-based Lyapunov function is derived and solved for smooth joint trajectory and restorable base trajectories. In the method, the state equation is first proposed for dual-arm robots with and without end constraints, and the system stability is analyzed to obtain the system input. The input modification further increases the system stability and simplifies the calculation complexity. Simulations are carried out in the end, and the proposed method is validated in minimizing final base attitude change and trajectory smoothness. Moreover, the minute internal force during the coordinated operation and the considerable computing efficiency increases the feasibility of the method during space tasks.

关键词： free-floating space robot     dual arm     coordinated operation     base attitude restoration     bidirectional approach    

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Task-space position/attitude tracking control of FAST fine tuning system

QI Lin, ZHANG Hui, DUAN Guanghong

《机械工程前沿（英文）》 2008年 第3卷 第4期   页码 392-399 doi: 10.1007/s11465-008-0056-8

摘要： This paper addresses the task-space position/attitude tracking control of a suspended parallel robot, which is being developed in the framework of a five-hundred meter aperture spherical radio telescope (FAST) project. Based on the quaternion algebra, a novel model-independent task-space PD controller that ensures end-effector position and attitude tracking is presented. The simulation and experimental results show that the new controller has better control effects than the traditional joint-space controller.

关键词： telescope     five-hundred     end-effector     controller     simulation    

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Study of base friction simulation tests based on a complicated engineered bridge slope

Liu HE, Guang WU, Hua WANG

《结构与土木工程前沿（英文）》 2012年 第6卷 第4期   页码 393-397 doi: 10.1007/s11709-012-0174-6

摘要： In this paper, a physical base friction test model of a slope is established. The model is based on similarity principles and the geological conditions of a complicated bridge slope during construction, deformation and failure. The behavior of the slope in both its natural state and during excavation loading is qualitatively analyzed through base friction tests. The base friction test results are then subjected to comparison and analysis using finite element numerical simulation. The findings show that the whole engineered slope tends to stabilize in its natural state, whereas instabilities will arise at faulted rock masses located near bridge piers during excavation loading. Therefore, to ensure normal construction operation of bridge works, it is suggested that pre-reinforcement of faulted rock masses be performed.

关键词： base friction test     slope stability evaluation     bridge slope    

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River restoration challenges with a specific view on hydromorphology

Jianhua LI, Stephan HOERBINGER, Clemens WEISSTEINER, Lingmin PENG, Hans Peter RAUCH

《结构与土木工程前沿（英文）》 2020年 第14卷 第5期   页码 1033-1038 doi: 10.1007/s11709-020-0665-9

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Restoration of hyper-eutrophic water with a modularized and air adjustable constructed submerged plant

Jinzhong LI, Xueju LI, Shujuan SUN, Xuegong LIU, Suiliang HUANG

《环境科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 573-584 doi: 10.1007/s11783-011-0363-x

摘要： A modularized and air adjustable constructed submerged plant bed (CSPB) which can be used to restore the eutrophic water is introduced in this paper. This plant bed helps hydrophyte grow under poor conditions such as frequently changed water depth, impaired water transparency, algae bloom and substantial duckweed in summer, which are not naturally suitable for growing hydrophyte. This pilot study in Waihuan River of Tianjin, China, revealed that reduction of Chemical Oxygen Demand (COD), Total Nitrogen (TN) and Total Phosphorus (TP) by the use of CSPB could be reached 30%–35%, 35%–40%, 30%–40% respectively in the growing season (from March to October) and 5%–10%, 5%–15%, 7%–20% respectively in the winter (from November to February) when the detention time was 6 d. The relationships between the concentration of COD, TN, TP and the detention time fit the first-order kinetic equation well and the coefficients of determination ( ) were all above 0.9. The attenuation coefficients k of the kinetic equation were a function of the water temperature. When the water temperature was quite low or quite high, was not significantly changed with increasing or decreasing water temperature. While when the temperature was in a moderate range, an increase or decrease of water temperature would lead to a rapid increase or decrease in .

关键词： modularized and air adjustable constructed submerged plant bed     water purification     eco-restoration techniques     aquatic plants     eutrophication    

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燃油喷雾形态主动控制的可能性 Review

Masataka Arai

《工程（英文）》 2019年 第5卷 第3期   页码 519-534 doi: 10.1016/j.eng.2019.04.010

摘要：

内燃机（ICE）对于汽车是有吸引力的动力源，具有良好的可储存性、可运输性，同时需要供应高能量密度的液体燃料。具有高性能和低环境危害的紧凑型内燃机是内燃机发展趋势。未来必须把燃油喷雾智能主动控制的燃烧作为解决传统内燃机相关重大问题（如排放）的突破性技术。已发展出在喷雾期间形成预期的燃料喷射速率和喷射模式的技术，并且传统内燃机可以在一定程度上控制燃烧。但是在燃烧范围内，燃料在空间上的扩散并未取得预期进展。因此，对于燃烧的智能控制，新且有效的燃油喷雾主动控制技术是非常必要的。空化、闪蒸、喷雾- 喷雾相互作用、喷雾-壁面相互作用和空气流动是有可能实现燃油喷雾形态主动控制的基础。本文使用文献中的论据来讨论未来喷雾燃烧的智能紧凑内燃机中喷雾形态主动控制技术的可能性。

关键词： 内燃机，燃料喷雾，喷雾控制，喷雾形态，喷油器    

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Base editors: development and applications in biomedicine

《医学前沿（英文）》 2023年 第17卷 第3期   页码 359-387 doi: 10.1007/s11684-023-1013-y

摘要： Base editor (BE) is a gene-editing tool developed by combining the CRISPR/Cas system with an individual deaminase, enabling precise single-base substitution in DNA or RNA without generating a DNA double-strand break (DSB) or requiring donor DNA templates in living cells. Base editors offer more precise and secure genome-editing effects than other conventional artificial nuclease systems, such as CRISPR/Cas9, as the DSB induced by Cas9 will cause severe damage to the genome. Thus, base editors have important applications in the field of biomedicine, including gene function investigation, directed protein evolution, genetic lineage tracing, disease modeling, and gene therapy. Since the development of the two main base editors, cytosine base editors (CBEs) and adenine base editors (ABEs), scientists have developed more than 100 optimized base editors with improved editing efficiency, precision, specificity, targeting scope, and capacity to be delivered in vivo, greatly enhancing their application potential in biomedicine. Here, we review the recent development of base editors, summarize their applications in the biomedical field, and discuss future perspectives and challenges for therapeutic applications.

关键词： base editing     CBE     ABE     ADAR     DdCBE     disease model     therapeutic application    

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Multistage-batch bipolar membrane electrodialysis for base production from high-salinity wastewater

《化学科学与工程前沿（英文）》 2022年 第16卷 第5期   页码 764-773 doi: 10.1007/s11705-021-2114-2

摘要： Bipolar membrane electrodialysis (BMED) is considered a state-of-the-art technology for the conversion of salts into acids and bases. However, the low concentration of base generated from a traditional BMED process may limit the viability of this technology for a large-scale application. Herein, we report an especially designed multistage-batch (two/three-stage-batch) BMED process to increase the base concentration by adjusting different volume ratios in the acid (Vacid), base (Vbase), and salt compartments (Vsalt). The findings indicated that performance of the two-stage-batch with a volume ratio of Vacid:Vbase:Vsalt = 1:1:5 was superior in comparison to the three-stage-batch with a volume ratio of Vacid:Vbase:Vsalt = 1:1:2. Besides, the base concentration could be further increased by exchanging the acid produced in the acid compartment with fresh water in the second stage-batch process. With the two-stage-batch BMED, the maximum concentration of the base can be obtained up to 3.40 mol∙L–1, which was higher than the most reported base production by BMED. The low energy consumption and high current efficiency further authenticate that the designed process is reliable, cost-effective, and more productive to convert saline water into valuable industrial commodities.

关键词： bipolar membrane electrodialysis     multistage-batch     base production     high-salinity wastewater    

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Enzyme@bismuth-ellagic acid: a versatile platform for enzyme immobilization with enhanced acid-base stability

《化学科学与工程前沿（英文）》 2023年 第17卷 第6期   页码 784-794 doi: 10.1007/s11705-022-2278-4

摘要： In situ encapsulation is an effective way to synthesize enzyme@metal–organic framework biocatalysts; however, it is limited by the conditions of metal–organic framework synthesis and its acid-base stability. Herein, a biocatalytic platform with improved acid-base stability was constructed via a one-pot method using bismuth-ellagic acid as the carrier. Bismuth-ellagic acid is a green phenol-based metal–organic framework whose organic precursor is extracted from natural plants. After encapsulation, the stability, especially the acid-base stability, of amyloglucosidases@bismuth-ellagic acid was enhanced, which remained stable over a wide pH range (2–12) and achieved multiple recycling. By selecting a suitable buffer, bismuth-ellagic acid can encapsulate different types of enzymes and enable interactions between the encapsulated enzymes and cofactors, as well as between multiple enzymes. The green precursor, simple and convenient preparation process provided a versatile strategy for enzymes encapsulation.

关键词： bismuth-ellagic acid     in situ encapsulation     enzyme@MOF biocomposites    

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Application of Cu nanoparticles as N32 base oil additives

Qiang HE, Jun YE, Hongzhao LIU, Jinling LI,

《机械工程前沿（英文）》 2010年 第5卷 第1期   页码 93-97 doi: 10.1007/s11465-009-0083-0

摘要： Cu nanoparticles as N32 base oil additives are studied in the paper and their structure is characterized by transmission electron microscopy (TEM) and X-ray powder diffraction spectroscopy (XRD). The widely used steel-steel friction system is chosen to test the feasibility and practicality of Cu nanoparticles as bearing lubricant additives. The results show that N32 base oil with 0.5% Cu nanoparticle can improve the test sample contact fatigue life than pure N32 base oil.

关键词： Cu nanoparticle     tribological property     contact fatigue     weibull distribution    

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Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

《化学科学与工程前沿（英文）》 2021年 第15卷 第6期   页码 1514-1523 doi: 10.1007/s11705-021-2092-4

摘要： A base-free catalytic system for the aerobic oxidation of 5-hydroxymethyl-2-furfural was exploited by using Pt nanoparticles immobilized onto a thermoresponsive poly(acrylamide-co-acrylonitrile)-b-poly(N-vinylimidazole) block copolymer, with an upper critical solution temperature of about 45 °C. The Pt nanocatalysts were well-dispersed and highly active for the base-free oxidation of 5-hydroxymethyl-2-furfural by molecular oxygen in water, affording high yields of 2,5-furandicarboxylic acid (up to>99.9%). The imidazole groups in the block copolymer were conducive to the improvement of catalytic performance. Moreover, the catalysts could be easily separated and recovered based on their thermosensitivity by cooling the reaction system below the upper critical solution temperature. Good stability and reusability were observed over these copolymer-immobilized catalysts with no obvious decrease in catalytic activity in the five consecutive cycles.

关键词： aerobic oxidation     base-free     5-hydroxymethyl-2-furfural     Pt nanoparticle     thermoresponsive block copolymer    

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可拓知识库系统及其应用

李立希,李嘉

《中国工程科学》 2001年 第3卷 第3期   页码 61-64

摘要：

知识库系统是一种专门存储、管理大量知识的机构。文章以可拓学的理论和方法为指导，提出可拓知识表示法和可拓知识库系统的特点与构架。给出了可拓知识表示的形式化语义，其基本单元是知识物元；阐述了矛盾问题求解的形式表示，其核心是问题的物元模型，通过可拓算子把不相容问题转化为相容问题；相关方式推理是可拓知识库系统推理机的特点，是传统规则推理的推广。可拓知识库采用可拓知识表示方法，是传统知识库的一个超集；可拓知识库系统由目标库、条件库、公用知识库、分类知识库、推理机与知识库管理系统组成。

关键词： 可拓论     不相容     知识库    

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长江经济带水安全保障与水生态修复策略研究

胡春宏,张双虎

《中国工程科学》 2022年 第24卷 第1期   页码 166-175 doi: 10.15302/J-SSCAE-2022.01.018

摘要：

“共抓大保护、不搞大开发”是推动长江经济带高质量发展的战略导向，长江大保护要抓主要问题、采取针对性的措施策略。本文系统分析了长江经济带面临的主要水安全与水生态保护修复问题：防洪安全形势依然严峻、水生动物适宜生境萎缩严重且多样性降低、长江与通江湖泊关系失调。研究提出了针对性的水安全保障措施与水生态修复策略：一是加快重要蓄滞洪区的安全工程建设，修订《长江流域防洪规划》，提高防洪保安能力；二是在长江上游支流替代生境建设，在长江中下游实施部分原通江湖泊的恢复连通并扩大水库生态调度范围，修复受损生态系统；三是实施洞庭湖北部四口水系综合整治，在鄱阳湖出口建闸并进行调控，科学改善江湖关系。

关键词： 长江经济带     水安全保障     水生态修复     防洪安全     生态重建     江湖关系    

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Process study on adsorption of glycerin from saline wastewater by strong base anion resin

Haitao ZHANG, Xiaoqing MA, Xian QU, Jeanpierre Arcangeli

《化学科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 113-116 doi: 10.1007/s11705-010-0547-0

摘要： A physicochemical method was used to adsorb glycerin in saline wastewater by strong base anion resin (D201). Boric acid, a kind of weak acid, can combine with glycerin, and a specific complex can be produced, which possess bigger molecule than glycerin. Then, this specific complex could be adsorbed by strong base anion resin. Via the experiment, the equation of adsorption isotherm with D201 at 20°C can be shown by lg / = 1.74lg - 5.72; for column test with simulative glycerin wastewater, the treatment capability was more than nine bed volumes, and 39.77 mg glycerin could be removed by per gram resin. When the NaCl concentration was 10 g/L, five bed volumes of simulative wastewater could be treated, and the adsorb mass was 29.09 mg/g. When the NaCl concentration was 30 g/L, only three bed volumes of simulative wastewater could be treated, and the adsorb mass was 14.83 mg/g.

关键词： glycerin     anion resin     boric acid     wastewater     NaCl    

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Heat-spreading analysis of a heat sink base embedded with a heat pipe

B. V. BORGMEYER, H. B. MA,

《能源前沿（英文）》 2010年 第4卷 第2期   页码 143-148 doi: 10.1007/s11708-010-0013-1

摘要： A simplified model predicting the heat transfer performance of a heat sink base with a high thermal conductivity was developed. Numerical analysis was performed using the commercial software FLUENT. The investigation indicates that for heat sink bases with a high effective thermal conductivity, such as the base embedded with a typical heat pipe, the entire heat sink can be modeled as a flat plate with a uniform temperature and an effective convection heat transfer coefficient. This simplified model can be used to determine the heat transfer performance of a heat sink embedded with a typical heat pipe or vapor chamber.

关键词： heat pipe     heat sink     microprocessor heat removal    

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标题 作者 时间 类型 操作

Trajectory planning and base attitude restoration of dual-arm free-floating space robot by enhanced bidirectional

Zongwu XIE1 , Xiaoyu ZHAO1 , Zainan JIANG1 , Haitao YANG2 , Chongyang LI1

期刊论文

Task-space position/attitude tracking control of FAST fine tuning system

QI Lin, ZHANG Hui, DUAN Guanghong

期刊论文

Study of base friction simulation tests based on a complicated engineered bridge slope

Liu HE, Guang WU, Hua WANG

期刊论文

River restoration challenges with a specific view on hydromorphology

Jianhua LI, Stephan HOERBINGER, Clemens WEISSTEINER, Lingmin PENG, Hans Peter RAUCH

期刊论文

Restoration of hyper-eutrophic water with a modularized and air adjustable constructed submerged plant

Jinzhong LI, Xueju LI, Shujuan SUN, Xuegong LIU, Suiliang HUANG

期刊论文

燃油喷雾形态主动控制的可能性

Masataka Arai

期刊论文

Base editors: development and applications in biomedicine

期刊论文

Multistage-batch bipolar membrane electrodialysis for base production from high-salinity wastewater

期刊论文

Enzyme@bismuth-ellagic acid: a versatile platform for enzyme immobilization with enhanced acid-base stability

期刊论文

Application of Cu nanoparticles as N32 base oil additives

Qiang HE, Jun YE, Hongzhao LIU, Jinling LI,

期刊论文

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

期刊论文

可拓知识库系统及其应用

李立希,李嘉

期刊论文

长江经济带水安全保障与水生态修复策略研究

胡春宏,张双虎

期刊论文

Process study on adsorption of glycerin from saline wastewater by strong base anion resin

Haitao ZHANG, Xiaoqing MA, Xian QU, Jeanpierre Arcangeli

期刊论文

Heat-spreading analysis of a heat sink base embedded with a heat pipe

B. V. BORGMEYER, H. B. MA,

期刊论文