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Chinese Journal of Aeronautics 2024年第2期37卷 471-481页

作者： Li WANG Jiang LI Kang LI Yiwei WANG Chenyang MA Science and technology on Combustion Internal Flow and Thermal-Structure LaboratoryNorthwestern Polytechnical UniversityXi’an 710072China

Carbon Nanotubes(CNTs)reinforced Polymer-Matrix Composites(PMCs)is widely used as insulation materials in thermal protection system of aerospace ***,CNTs are prone to oxidation and have high thermal conductivities,which makes it difficult to improve the ablation resistance of insulation materials that contain ***_(2)was encapsulated onto the surface of CNTs(CNTs@SiO_(2)),which were then added to Ethylene Propylene Diene Monomer(EPDM)rubber to prepare the insulation *** analysis and ablation test were used to evaluate the resistance of the insulation materials to thermal oxidation and ***,scanning electron microscopy was performed to analyze their *** revealed that the addition of CNTs@SiO_(2)could visibly reduce the effects of hot corrosion and ablation on insulation *** C-CNTs@SiO_(2)-1 formulation had the best ablative ***,compared with the unencapsulated formulation(C-CNTs-10),the C-CNTs@SiO_(2)-1 formulation reduced the line ablation rate by 51%to 0.0130 mm/s after oxygen-acetylene ***,the ablation mechanism was investigated based on the effects of the CNTs@SiO_(2)additive on their ***,the improvement in ablation performance may be attributed to CNTs@SiO_(2)-induced decreases in thermal conductivity,improvement in the hot corrosion resistance in the char layer,and changes in the microstructure.

关键词： Polymer-Matrix Composites(PMCs) Carbon Nanotubes(CNTs) thermal properties Ablation Oxidation

Spectral Selectivity of CdTe Cells with Substrate Configuration for photovoltaic/thermal Applications

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Journal of thermal Science 2024年第4期33卷 1542-1553页

作者： CHEN Ken HU Kongfu ZHAO Bin CHEN Tao HAO Yong PEI Gang Department of thermal Science and Energy Engineering University of Science and Technology of ChinaHefei230027China Key laboratory of solar thermal Conversion of Anhui Province Hefei230027China Hefei National laboratory for Physical Sciences at Microscale Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei230026China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

Existing photovoltaic cells with high infrared emissivity generate huge radiative heat loss in photovoltaic/thermal applications and degrade the photothermal *** purpose of this work is to evaluate the full spectral absorptivity of CdTe cells to find a spectrally selective photovoltaic cell for photovoltaic/thermal *** this end,the solar absorptivity and mid-infrared thermal emissivity of CdTe cells were tested by ellipsometry,UV-Vis-NIR spectrophotometer,and Fourier transform infrared *** experimental results show that the AM 1.5 solar spectrum weighted absorptivity of the substrate configuration CdTe cell reaches 0.91,and the mid-infrared emissivity is only 0.29,while the superstrate configuration cell emissivity is as high as *** research shows that substrate configuration with a transparent conductive layer on top can be flexibly grown on metal foils and has spectral selectivity with high solar absorptivity and low mid-infrared emissivity should be considered in the future for photovoltaic/thermal applications.

关键词： photovoltaic/thermal spectral selectivity substrate configuration CdTe cell ITO

Singularity analysis and avoidance for an SSRMS-type reconfigurable space manipulator with a non-spherical wrist and two lockable passive telescopic links

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Chinese Journal of Aeronautics 2024年第8期37卷 435-459页

作者： Zhiyuan ZHAO Xiaohang YANG Yuntao LI Zichun XU Jingdong ZHAO Hong LIU State Key laboratory of Robotics and system Harbin Institute of TechnologyHarbin 150001China

This study focuses on addressing kinematic singularity analysis and avoidance issues for a space station remote manipulator system(SSRMS)-type reconfigurable space *** manipulator is equipped with a non-spherical wrist and two lockable passive telescopic links(LPTLs),which enable it to have both active revolute and passive prismatic joints and operate in two distinct *** begin with the kinematic singularity analysis,the study derives the differential kinematic equations for the manipulator and identifies the dominant Jacobian matrix that causes ***,an in-depth analysis of singularities from multiple perspectives is ***,a kinematic singularity map method is proposed to capture the distribution of singularities within the reachable ***,the influence of the two LPTLs on singularities is thoroughly ***,a new method based on the matrix rank equivalence principle is introduced to determine singularity conditions,enabling the identification of all the singular configurations for the SSRMS-type reconfigurable ***,this method significantly reduces computational complexity,and the singularity conditions obtained have more concise *** the singularity avoidance problem,a novel method is developed,which simultaneously addresses the requirements of real-time performance,high precision,and the avoidance of both kinematic singularities and joint limit *** from these excellent properties,the proposed method can effectively resolve the singularity issues encountered separately by the SSRMS-type reconfigurable manipulator in its two operational *** typical simulations validate the utility of all the proposed methods.

关键词： Reconfigurable space manipulator Redundant manipulator Kinematics Singularity analysis Singularity avoidance

Inkjet-Printing Controlled Phase Evolution Boosts the Efficiency of Hole Transport Material Free and Carbon-Based CsPbBr_(3) Perovskite solar Cells Exceeding 9%

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Energy & Environmental Materials 2024年第2期7卷 209-220页

作者： Lihua Zhang Shi Chen Jie Zeng Zhengyan Jiang Qian Ai Xianfu Zhang Bihua Hu Xingzhu Wang Shihe Yang Baomin Xu Department of Materials Science and Engineering and Shenzhen Engineering Research and Development Center for Flexible solar Cells Southern University of Science and TechnologyShenzhen 518055China Department of Chemistry The Hong Kong University of Science and TechnologyClear Water BayHong KongChina Henan Key laboratory of photovoltaic Materials Henan UniversityKaifeng 475004China Guangdong Key Lab of Nano-Micro Material Research School of Chemical Biology and BiotechnologyShenzhen Graduate SchoolPeking UniversityShenzhen 518055China Key University laboratory of Highly Efficient Utilization of solar Energy and Sustainable Development of Guangdong Southern University of Science and TechnologyShenzhen 518055China Guangdong-Hong Kong-Macao Joint laboratory for Photonic-thermal-Electrical Energy Materials and Devices Southern University of Science and TechnologyShenzhen 518055China

Hole transport material free carbon-based all-inorganic CsPbBr_(3)perovskite solar cells(PSCs)are promising for commercialization due to its low-cost,high open-circuit voltage(V_(oc))and superior *** to the different solubility of PbBr_(2)and CsBr in conventional solvents,CsPbBr_(3)films are mainly obtained by multi-step spin-coating through the phase evolution from PbBr_(2)to CsPb_(2)Br_(5)and then to CsPbBr_(3).The scalable fabrication of high-quality CsPbBr_(3)films has been rarely ***,an inkjet-printing method is developed to prepare high-quality CsPbBr_(3)*** formation of long-range crystalline CsPb_(2)Br_(5)phase can effectively improve phase purity and promote regular crystal stacking of CsPbBr_(3).Consequently,the inkjet-printed CsPbBr_(3)C-PSCs realized PCEs up to 9.09%,8.59%and 7.81%with active areas of 0.09,0.25,and 1 cm^(2),respectively,demonstrating the upscaling potential of our fabrication method and *** high performance is mainly ascribed to the high purity,strong crystal orientation,reduced surface roughness and lower trap states density of the as-printed CsPbBr_(3)*** work provides insights into the relationship between the phase evolution mechanisms and crystal growth dynamics of cesium lead bromide halide films.

关键词： all-inorganic perovskite solar cells CsPbBr_(3) inkjet-printing phase evolution

A Multi-Strategy-Improved Northern Goshawk Optimization Algorithm for Global Optimization and Engineering Design

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Computers, Materials & Continua 2024年第7期80卷 1677-1709页

作者： Liang Zeng Mai Hu Chenning Zhang Quan Yuan Shanshan Wang School of Electrical and Electronic Engineering Hubei University of TechnologyWuhan430068China Hubei Key laboratory for High-Efficiency Utilization of solar Energy and Operation Control of Energy Storage system Hubei University of TechnologyWuhan430068China

Optimization algorithms play a pivotal role in enhancing the performance and efficiency of systems across various scientific and engineering *** enhance the performance and alleviate the limitations of the Northern Goshawk Optimization(NGO)algorithm,particularly its tendency towards premature convergence and entrapment in local optima during function optimization processes,this study introduces an advanced Improved Northern Goshawk Optimization(INGO)*** algorithm incorporates a multifaceted enhancement strategy to boost operational ***,a tent chaotic map is employed in the initialization phase to generate a diverse initial population,providing high-quality feasible ***,after the first phase of the NGO’s iterative process,a whale fall strategy is introduced to prevent premature convergence into local *** is followed by the integration of T-distributionmutation strategies and the State Transition Algorithm(STA)after the second phase of the NGO,achieving a balanced synergy between the algorithm’s exploitation and *** research evaluates the performance of INGO using 23 benchmark functions alongside the IEEE CEC 2017 benchmark functions,accompanied by a statistical analysis of the *** experimental outcomes demonstrate INGO’s superior achievements in function optimization ***,its applicability in solving engineering design problems was verified through simulations on Unmanned Aerial Vehicle(UAV)trajectory planning issues,establishing INGO’s capability in addressing complex optimization challenges.

关键词： Northern Goshawk Optimization tent chaotic map T-distribution disturbance state transition algorithm UAV path planning

A versatile humanoid robot platform for dexterous manipulation and human-robot collaboration

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CAAI Transactions on Intelligence technology 2024年第2期9卷 526-540页

作者： Xin Shu Fenglei Ni Xinyang Fan Shuai Yang Changyuan Liu Baoxu Tu Yiwei Liu Hong Liu State Key laboratory of Robotics and system Harbin Institute of TechnologyHarbinChina

Humanoid robots have attracted much attention by virtue of their compatibility with human ***,biped humanoids with immense promise still cannot function steadily and reliably in real-world settings in the current ***,rationally combining a humanoid robot with different stable mobile platforms is a favoured solution for diverse ***,a new versatile humanoid robot platform,aiming to provide a generic solution that can be flexibly deployed in diverse scenarios,for example,indoors and fields is *** humanoid robot platform incorporates multimodal perception,and extensible interfaces on hardware and software,allowing it to be rapidly integrated with different mobile platforms and end-effectors,only through easyto-assemble ***,the platform has achieved impressive integration,lightness,dexterity,and strength in its class,with human-like size and rich perception,targeted to have human-intelligent manipulation skills for human-engineered ***,this article elaborates on the reasoning behind the design choices,and outlines each ***,the essential performance of the platform is successfully demonstrated in a set of experiments with precise and dexterous manipulation,and human–robot collaboration requirements.

关键词： intelligent robots robotics

Design Optimization and Operating Performance of S-CO_(2) Brayton Cycle under Fluctuating Ambient Temperature and Diverse Power Demand Scenarios

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Journal of thermal Science 2024年第1期33卷 190-206页

作者： YANG Jingze YANG Zhen DUAN Yuanyuan Key laboratory for thermal Science and Power Engineering of MOE Beijing Key Laboratory for CO_(2) Utilization and Reduction TechnologyTsinghua UniversityBeijing 100084China

The supercritical CO_(2)(S-CO_(2)) Brayton cycle is expected to replace steam cycle in the application of solar power tower system due to the attractive potential to improve efficiency and reduce *** the concentrated solar power plant with thermal energy storage is usually located in drought area and used to provide a dispatchable power output,the S-CO_(2) Brayton cycle has to operate under fluctuating ambient temperature and diverse power demand *** addition,the cycle design condition will directly affect the off-design *** this work,the combined effects of design condition,and distributions of ambient temperature and power demand on the cycle operating performance are analyzed,and the off-design performance maps are proposed for the first time.A cycle design method with feedback mechanism of operating performance under varied ambient temperature and power demand is introduced *** show that the low design value of compressor inlet temperature is not conductive to efficient operation under low loads and sufficient output under high ambient *** average yearly efficiency is most affected by the average power demand,while the load cover factor is significantly influenced by the average ambient *** multi-objective optimization,the optimal solution of designed compressor inlet temperature is close to the minimum value of35℃ in Delingha with low ambient temperature,while reaches 44.15℃ in Daggett under the scenario of high ambient temperature,low average power demand,long duration and large value of peak load during the peak temperature *** the cycle designed with compressor inlet temperature of 35℃ instead of 44.15℃ in Daggett under light industry power demand,the reduction of load cover factor will reach 0.027,but the average yearly efficiency can barely be improved.

关键词： supercritical CO_(2)Brayton cycle ambient temperature fluctuating power demand scenarios design optimization off-design performance

thermal Property Enhancement of a Novel Shape-Stabilized Sodium Acetate Trihydrate-Acetamide/Expanded Graphite-Based Composite Phase Change Material

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Journal of thermal Science 2024年第4期33卷 1564-1576页

作者： AN Zhoujian HOU Wenjie DU Xiaoze HUANG Zhongzheng MOMBEKI PEA Hamir Johan ZHANG Dong LIU Xiaomin College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou730050China Key laboratory of Multi-supply system with solar Energy and Biomass of Gansu Province Lanzhou730050China Gansu Natural Energy Research Institute Lanzhou730046China

Phase change materials(PCMs)are a kind of highly efficient thermal storage materials which have a bright application prospect in many fields such as energy conservation in buildings,waste heat recovery,battery thermal management and so *** inorganic hydrated salt PCMs have received increasing attention from researchers due to their advantages of being inexpensive and ***,inorganic hydrated salt PCMs are still limited by the aspects of inappropriate phase change temperature,liquid phase leakage,large supercooling and severe phase separation in the application *** this work,sodium acetate trihydrate was selected as the basic inorganic PCM,and a novel shape-stabilized composite phase change material(CPCM)with good thermal properties was prepared by adding various functional *** first,the sodium acetate trihydrate-acetamide binary mixture was prepared and the melting point was adjusted using *** the binary mixture was incorporated into expanded graphite to synthesize a novel shape-stabilized *** thermophysical properties of the resultant shape-stabilized CPCM were systematically *** microscopic morphology and chemical structure of the obtained shape-stabilized CPCM were characterized and *** experiment results pointed out that acetamide could effectively lower the melting point of sodium acetate *** obtained shape-stabilized CPCM modified with additional 18%(mass fraction)acetamide and 12%(mass fraction)expanded graphite exhibited good shape stability and thermophysical characteristics:a low supercooling degree of 1.75℃and an appropriate melting temperature of 40.77℃were obtained;the latent heat of 151.64 kJ/kg and thermal conductivity of 1.411 W/(m·K)were also ***,after 50accelerated melting-freezing cycles,the obtained shape-stabilized CPCM represented good thermal reliability.

关键词： sodium acetate trihydrate melting point modification agent expanded graphite shape stability thermal conductivity enhancement

Combustion characteristics of millimeter-sized aluminum particles in fluidized bed under various O_(2)/CO_(2)/H_(2)O atmospheres Author links open overlay panel

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Particuology 2024年第8期91卷 315-322页

作者： Jialing Zhou Rui Zhang Dong Liu Key laboratory of thermal Control of Electronic Equipment Ministry of Industry and Information TechnologyNanjing210094China Advanced Combustion laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing210094China

Aluminum is an attractive alternative fuel,but it burns very inefficiently due to the formation of a dense Al_(2)O_(3)layer which prevents O_(2)from diffusion to the surface of Al *** previous experiments,the combustion of millimeter-sized Al(mAl)particles in the fluidized bed has achieved a substantial increase in the combustion efficiency,but further improvements are still *** this study,the effects of reaction atmosphere on the fluidized combustion of mAl particles were *** experiments with different O_(2)/H_(2)O/CO_(2)concentrations were *** experimental results indicate that the combustion efficiency of mAl particles in fluidized bed increases as the mole fraction of O_(2),H_(2)O or CO_(2)increases,and the highest combustion efficiency can reach 38.7%.After the analysis of the oxide film on the surface of aluminum particles,it was found that it is easier to generate the unstableθ-Al_(2)O_(3)under CO_(2)atmosphere,and it is easier to generate the unstableγ-Al_(2)O_(3)andθ-Al_(2)O_(3)under H_(2)O *** unstable Al_(2)O_(3)film is more likely to be abraded in the fluidized bed,which leads to the effective improvement of the combustion efficiency.

关键词： Al combustion Fluidized bed Atmosphere Combustion efficiency

Minimal Context-Switching Data Race Detection with Dataflow Tracking

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Journal of Computer Science & technology 2024年第1期39卷 211-226页

作者：郑龙李洋辛杰刘海峰郑然廖小飞金海 National Engineering Research Center for Big Data technology and system School of Computer Science and Technology Huazhong University of Science and TechnologyWuhan 430074China Services Computing technology and system laboratory School of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Cluster and Grid Computing laboratory School of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Data race is one of the most important concurrent anomalies in multi-threaded *** con-straint-based techniques are leveraged into race detection,which is able to find all the races that can be found by any oth-er sound race ***,this constraint-based approach has serious limitations on helping programmers analyze and understand data ***,it may report a large number of false positives due to the unrecognized dataflow propa-gation of the ***,it recommends a wide range of thread context switches to schedule the reported race(in-cluding the false one)whenever this race is exposed during the constraint-solving *** ad hoc recommendation imposes too many context switches,which complicates the data race *** address these two limitations in the state-of-the-art constraint-based race detection,this paper proposes DFTracker,an improved constraint-based race detec-tor to recommend each data race with minimal thread context ***,we reduce the false positives by ana-lyzing and tracking the dataflow in the *** this means,DFTracker thus reduces the unnecessary analysis of false race *** further propose a novel algorithm to recommend an effective race schedule with minimal thread con-text switches for each data *** experimental results on the real applications demonstrate that 1)without removing any true data race,DFTracker effectively prunes false positives by 68%in comparison with the state-of-the-art constraint-based race detector;2)DFTracker recommends as low as 2.6-8.3(4.7 on average)thread context switches per data race in the real world,which is 81.6%fewer context switches per data race than the state-of-the-art constraint based race ***,DFTracker can be used as an effective tool to understand the data race for programmers.

关键词： data race satisfiability modulo theory multi-threaded program dynamic detection