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Multi-disciplinary Conceptual Design Knowledge of Multi-stage Hybrid Rocket Using Data Mining Technique

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Journal of Mechanics engineering and Automation 2015年第1期5卷 1-9页

作者： Masahiro Kanazaki Kazuhisa Chiba Koki Kitagawa Toru Shimada Masashi Nakamiya Department of Aerospace engineering Graduate School of System Design Tokyo Metropolitan University Tokyo 191-0065Japan Graduate School of engineering Hokkaido University of Science Sapporo 006-8585 Japan institute of Space and Astronautical Science Japan Aerospace Exploration Agency Sagamihara 252-5210 Japan Research institute for Sustainable Humanosphere Kyoto University Kyoto 606-8501 Japan

This paper deals with the application of data mining techniques to the conceptual design knowledge for a LV （launch vehicle） with a HRE （hybrid rocket engine）. This LV is a concept of the space transportation, which can deliver micro-satellite to the SSO （sun-synchronous orbit）. To design the higher performance LV with HRE, the optimum size of each component, such as an oxidizer tank containing liquid oxidizer, a combustion chamber containing solid fuel, a pressurizing tank and a nozzle, should be acquired. The Kriging based ANOVA （analysis of variance） and SOM （self-organizing map） are employed as data mining techniques for knowledge discovery. In this study, the paraffin （FT-0070） is used as a propellant of HRE. Then, the relationship among LV performances and design variables are investigated through the analysis and the visualization. To calculate the engine performance, the regression rate is computed based on an empirical expression. The design knowledge is extracted for the design knowledge of the multi-stage LV with HRE by analysis using ANOVA and SOM. As a result, the useful design knowledge on the present design problem is obtained to design HRE for space transportation.

关键词： Hybrid rocket data mining techniques multidisciplinary design

Occurrence, partition behavior, source and ecological risk assessment of nitro-PAHs in the sediment and water of Taige Canal, China

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Journal of Environmental Sciences 2023年第2期124卷 782-793页

作者： Jijie Kong Tao Ma Xiaoyu Cao Weidi Li Fengxiao Zhu Huan He Cheng Sun Shaogui Yang Shiyin Li Qiming Xian School of Environment Nanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China The State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China Fujian Provincial Key laboratory of Eco-Industrial Green Technology College of Ecological and Resource EngineeringWuyi UniversityWuyishan 354300China Nanjing institute of Environmental Sciences Ministry of Ecology and EnvironmentNanjing 210042China

Nitrated polycyclic aromatic hydrocarbons(NPAHs)are widespread organic pollutants that possess carcinogenic and mutagenic properties,so they may pose a risk to the environment and human *** this study,the concentrations of 15 NPAHs and 16 polycyclic aromatic hydrocarbons(PAHs)in 30 surface water samples and 26 sediment samples were measured in 2018 from the Taige Canal,one of the main rivers flowing into Taihu Lake,*** total NPAH concentrations in water and sediment ranged from 14.7 to 235 ng/L and 22.9 to 96.5 ng/g dw,respectively.9-nitrophenanthrene(nd–76.3 ng/L)was the dominant compound in surface water,while 2+3-nitrofluoranthene(1.73–18.1 ng/g dw)dominated in *** PAHs,concentration ranging from 1,097 to 2,981 ng/L and 1,089 to 4,489 ng/g dw in surface water and sediment,*** was a strong positive correlation between the log octanol-water partition coefficient(Kow)and log sediment-water partition coefficient due to hydrophobic *** fugacity fraction value increased with the decrease of log Kow,and chrysene was transferred from water into *** residual NPAHs in surface water and sediment of the Taige Canal have partial *** engine and coal combustion emissions were probably the principal sources of NPAHs in surface water and *** results of ecological risk assessment showed that some NPAHs inwater(e.g,1-nitropyrene and 6-nitrochrysene)and sediment(e.g.,2-nitrobiphenyl,5-nitroacenaphthene,9-nitrophenanthrene and 2+3-nitrofluoranthene)had moderate ecological risks,which should be of concern.

关键词： Nitrated polycyclic aromatic hydrocarbons(NPAHs) Occurrence Partition behavior Source apportionment Ecological risk assessment

Implication from GRB 221009A:Can TeV emission come from the GRB prompt phase?

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Science China(Physics,Mechanics & Astronomy) 2023年第8期66卷 139-149页

作者： Kai Wang Zhi-Peng Ma Ruo-Yu Liu Yuan-Chuan Zou Zhuo Li Zi-Gao Dai Department of Astronomy School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratoryof Modern Astronomy and Astrophysics Ministry of EducationNanjing UniversityNanjing 20023China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

Recently,the B.O.A.T.(“brightest of all time”)gamma-ray burst,dubbed GRB 221009A,was detected by various ***,the GRB presented very-high-energy(VHE,energy above 0.1 Te V)gamma-ray emission with energy extending above 10 Te V,as reported by the Large High Altitude Air Shower Observatory(LHAASO).We here demonstrate that the VHE and especially>10 Te V emission may originate from the internal hadronic dissipation of the GRB,without the need of invoking any exotic processes as suggested by some previous *** possible prompt origin of LHAASO photons may imply the first detection of the GRB prompt phase in the VHE *** also discuss the constraints on the properties of the GRB ejecta from multiwavelength and multi-messenger observations,which favors a magnetically dominated GRB *** suggested Poynting-flux-dominated GRB ejecta in this work supports the Blandford&Znajek(BZ)mechanism as the possible central engine model of GRB,as well as the possible strong magnetic dissipation and acceleration.

关键词： cosmological neutrinos neutrino astronomy high energy astrophysics gamma-ray bursts cosmic rays

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Chemical characterization of submicron aerosol particles during wintertime in a northwest city of China using an Aerodyne aerosol mass spectrometry

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Chemical characterization of submicron aerosol particles dur...

Exploring self-organization and self-adaption for smart manufacturing complex networks

第十五届海峡两岸气胶技术研讨会

作者： Xinghua Zhang Yangmei Zhang Junying Sun Yangchun Yu Francesco Canonaco Andre S.H.Prév?t Gang Li Key Laboratory of Arid Climatic Change and Reducing Disaster of Gansu Province Key Laboratory of Arid Climatic Change and Disaster Reduction of CMAInstitute of Arid MeteorologyChina Meteorological Administration State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological Sciences Shandong Academy for Environmental Planning Laboratory of Atmospheric Chemistry Paul Scherrer Institute (PSI) State Key Laboratory of Loess and Quaternary Geology and Key Laboratory of Aerosol Chemistry and Physics Institute of Earth EnvironmentChinese Academy of Sciences

An Aerodyne quadruple aerosol mass spectrometry(Q-AMS) was utilized to measure the size-resolved chemical composition of non-refractory submicron particles(NR-PM1) from October 27 to December 3,2014 at an urban site in Lanzhou,northwest *** average NR-PM1 mass concentration was 37.3 mg m(ranging from 2.9 to 128.2 mg m) under an AMS collection efficiency of unity and was composed of organics(48.4%),sulfate(17.8%),nitrate(14.6%),ammonium(13.7%),and chloride(5.7%).Positive matrix factorization(PMF) with the multi-linear engine(ME-2) solver identified six organic aerosol(OA) factors,including hydrocarbon-like OA(HOA),coal combustion OA(CCOA),cooking-related OA(COA),biomass burning OA(BBOA) and two oxygenated OA(OOA1 and OOA2),which accounted for 8.5%,20.2%,18.6%,12.4%,17.8% and 22.5% of the total organics mass on average,*** emissions were the major sources of fine particulate matter(PM) and played an important role in causing high chemically resolved PM pollution during wintertime in *** trajectory analysis indicated that the long-range regional transport air mass from the westerly was the key factor that led to severe submicron aerosol pollution during wintertime in Lanzhou.

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Frontiers of engineering Management 2023年第2期10卷 206-222页

作者： Zhengang GUO Yingfeng ZHANG Sichao LIU Xi Vincent WANG Lihui WANG Key Laboratory of Industrial engineering and Intelligent Manufacturing of Ministry of Industry and Information Technology School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Electrical and Electronic engineering Imperial College LondonLondon SW72AZUK Department of Production engineering KTH Royal Institute of TechnologyStockholm 10044Sweden

Trends toward the globalization of the manufacturing industry and the increasing demands for small-batch,short-cycle,and highly customized products result in complexities and fluctuations in both external and internal manufacturing environments,which poses great challenges to manufacturing ***,recent advances in the Industrial Internet of Things(IIoT)and the widespread use of embedded processors and sensors in factories enable collecting real-time manufacturing status data and building cyber–physical systems for smart,flexible,and resilient manufacturing *** this context,this paper investigates the mechanisms and methodology of self-organization and self-adaption to tackle exceptions and disturbances in discrete manufacturing ***,a general model of smart manufacturing complex networks is constructed using scale-free networks to interconnect heterogeneous manufacturing resources represented by network vertices at multiple ***,the capabilities of physical manufacturing resources are encapsulated into virtual manufacturing services using cloud technology,which can be added to or removed from the networks in a plug-and-play ***,information,and financial assets are passed through interactive links across the ***,analytical target cascading is used to formulate the processes of self-organizing optimal configuration and self-adaptive collaborative control for multilevel key manufacturing resources while particle swarm optimization is used to solve local problems on network ***,an industrial case based on a Chinese engine factory demonstrates the feasibility and efficiency of the proposed model and method in handling typical *** simulation results show that the proposed mechanism and method outperform the event-triggered rescheduling method,reducing manufacturing cost,manufacturing time,waiting time,and energy consumption,with reasonable computational time.T

关键词： cyber–physical systems Industrial Internet of Things smart manufacturing complex networks self-organization and self-adaption analytical target cascading collaborative optimization

Trajectory Planning Method for Tractor-trailer System Based on Nonlinear Model Predictive Control

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Trajectory Planning Method for Tractor-trailer System Based ...

Physical origin of multi-wavelength emission of GRB 100418A and implications for its progenitor

第43届中国控制会议

作者： Bobo Jia Liang Gao Daiwei Li Yi Yang Mengyin Fu Shanshan Xie National Key Lab of Autonomous Intelligent Unmanned Systems Beijing Institute of Technology School of Automation Nanjing University of Science and Technology

The tractor-trailer system has the characteristics of high state dimension,complex constraints and poor internal stability in trajectory ***,this paper proposed a trajectory planning method for tractor-trailer system based on nonlinear model predictive control(NMPC) in static and dynamic ***,an NMPC optimization problem is formulated by constructing performance indicators and integrating the constraints of the ***,an approximate optimal path is found as a reference solution for the warm start of the optimization problem by RRT* sampling in high dimensional state ***,the NMPC problem is solved by Optimization engine(OpEn) ***,simulation in different scenarios demonstrated the effectiveness and efficiency of the proposed method.

关键词： Tractor-trailer System Trajectory Planning Nonlinear Model Predictive Control

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Research in Astronomy and Astrophysics 2012年第4期12卷 411-418页

作者： Lan-Wei Jia Xue-Feng Wu Hou-Jun Lti Shu-Jin Hou En-Wei Liang Department of Physics Guangzhou University Guangzhou 510006 China Department of Physics and GXU-NAOC Center for Astrophysics and Space Sciences Guangxi University Nanning 530004 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Department of Physics and Astronomy University of Nevada Las Vegas Las Vegas NV 89154 USA Department of Physics and institute of Theoretical Physics and Astrophysics Xiamen University Xiamen 361005 China

Swift GRB 100418A is a long burst at z = 0.624 without detection of any associated supernova （SN）. Its light curves in both the prompt and afterglow phases are similar to GRB 060614, a nearby long GRB without an associated SN. We analyze the observational data of this event and discuss the possible origins of its multiwavelength emission. We show that its joint light curve at 1 keV derived from Swift BAT and XRT observations is composed of two distinguished components. The first component, whose spectrum is extremely soft （Γ = 4.32）, ends with a steep decay segment, indicating the internal origin of this component. The second component is a slowly-rising, broad bump which peaks at ～ 10 5 s post the BAT trigger. Assuming that the late bump is due to onset of the afterglow, we derive the initial Lorentz factor （Γ 0 ） of the GRB fireball and find that it significantly deviates from the relation between the Γ 0 and isotropic gamma-ray energy derived from typical GRBs. We also check whether it follows the same anti-correlation between X-ray luminosity and the break time observed in the shallow decay phase of many typical GRBs, which is usually regarded as a signal of late energy injection from the GRB central engine. However, we find that it does not obey this correlation. We propose that the late bump could be contributed by a two-component jet. We fit the second component with an off-axis jet model for a constant medium density and find the late bump can be represented by the model. The derived jet half-opening angle is 0.30 rad and the viewing angle is 0.315 rad. The medium density is 0.05 cm 3 , possibly suggesting that it may be from a merger of compact stars. The similarity between GRBs 060614 and 100418A may indicate that the two GRBs are from the same population and the late bump observed in the two GRBs may be a signal of a two-component jet powered by the GRB central engine.

关键词： gamma-rays: bursts — individual: GRB 060614 GRB 100418A

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加速碳中和的能源载体和动力总成技术

同济大学学报（自然科学版） 2021年第S01期49卷 202-210页

作者： EL NAKSCHABANDI Mohamad Said INCI Ferhat FINK Anja WIEDEMANN Bernd SENS Marc BRAUER Maximilian VON ESSEN Carsten YUAN Yixi GOTTSCHALK Habil Wolfram KUNSTMANN Jürgen institute of Land and Sea Transport Technical University Berlin德国柏林10587 Powertrain Systems Development IAV GmbH德国柏林10587 Ice Field Dry Ice engineering GmbH 德国法兰克福65926

由于“巴黎协定”和中国碳中和的气候保护目标及对能源独立的追求,需要加速对节能减排和二氧化碳中和的技术研究与开发。目前,在汽车动力系统的节能减排与碳中和方面,主要有3种发展概念:电池驱动;燃料电池驱动;基于二氧化碳中和的内燃... 详细信息

由于“巴黎协定”和中国碳中和的气候保护目标及对能源独立的追求,需要加速对节能减排和二氧化碳中和的技术研究与开发。目前,在汽车动力系统的节能减排与碳中和方面,主要有3种发展概念:电池驱动;燃料电池驱动;基于二氧化碳中和的内燃机可持续合成燃料驱动。根据能源使用的生命周期,将效率因素简化归纳为决策因素,在时间上无法反映出减少二氧化碳排放及减少化石能源的需求。与必要的能源供应相比,可再生能源的区域可用性有限,因此须以成本效益优势的方式来解决化石能源大规模替代的技术与基础建设问题。除了直接使用可再生电力外,绿色氢气和衍生的合成燃料可以大大加快化石能源的替代。短期内,合成燃料可以实施到全球的现有车辆上(约12亿辆),并持续增加混合汽油、柴油或天然气的混合比例,直到化石能源完全被绿色的氢气、合成燃料或电力所取代。介绍了氢气动力系统(H2内燃机和燃料电池动力系统)与合成燃料相关的技术解决方案。

关键词：内燃机合成燃料甲醇氢气动力系统

Performance of rotating detonation engine with stratified injection

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2020年第9期21卷 734-744页

作者： Zhi-di LEI Xiao-quan YANG Jue DING Pei-fen WENG Xun-nian WANG Shanghai Key Laboratory of Mechanics in Energy engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China

In this study,a numerical study based on Euler equations and coupled with detail chemistry model is used to improve the propulsion performance and stability of the rotating detonation *** proposed fuel injection called stratified injection functions by suppressing the isobaric combustion process occurring on the contact surface between fuel and detonation products,and thus the proportion of fuel consumed by detonation wave increases from 67%to 95%,leading to more self-pressure gain and lower entropy generation.A pre-mixed hydrogen-oxygen-nitrogen mixture is used as a reactive *** computational results show that the propulsion performance and the operation stability of the engine with stratified injection are both improved,the temperature of the flow field is notably decreased,the specific impulse of the engine is improved by 16.3%,and the average temperature of the engine with stratified injection is reduced by 19.1%.

关键词： Rotating detonation engine Injection pattern Propulsion performance Instability