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Thermodynamic Analysis and Optimization of an Irreversible Maisotsenko-Diesel Cycle

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Journal of Thermal Science 2019年第4期28卷 659-668页

作者： ZHU Fuli CHEN Lingen WANG Wenhua College of Power engineering Naval University of EngineeringWuhan 430033China institute of Thermal Science and Power engineering Wuhan Institute of TechnologyWuhan 430205China School of Mechanical & Electrical engineering Wuhan Institute of TechnologyWuhan 430205China

So far,Maisotsenko cycle has been applied to many fields such as heating ventilation and air-conditioning,power industry,chemical production,and so on.A lot of researches about classical thermodynamic analyses of Maisotsenko cycle have been made.A new cycle model of combined Diesel and Maisotsenko cycles considering heat transfer loss(HTL),piston friction loss(PFL)and internal irreversible loss(IIL)was proposed in this *** using the finite time thermodynamic(FTT)theory,the power and efficiency performances of the Maisotsenko-Diesel cycle(MDC)were *** of mass flow rate(MFR)of water injection in the Maisotsenko air saturator(MAS)and the other parameters related to the design of Diesel engine on the optimal cycle performances were ***,it was testified that irreversible MDC was superior than conventional irreversible Diesel cycle in both power output and thermal *** results can expand the application of Maisotsenko cycle(M-cycle)and provide some theoretical guidelines for the practical devices.

关键词： Maisotsenko-Diesel cycle finite-time thermodynamics power output thermal efficiency performance optimization

Constrained nonlinear MPC for accelerated tracking piece-wise references and its applications to thermal systems

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Control Theory and Technology 2022年第1期20卷 69-79页

作者： Defeng He Qingsong Wang Ping Han Haiping Du College of Information engineering Zhejiang University of TechnologyHangzhou310023ZhejiangChina School of Electrical Computer and Telecommunications EngineeringUniversity of WollongongWollongongNSW2522Australia

In this paper,we propose a model predictive control(MPC)strategy for accelerated offset-free tracking piece-wise constant reference signals of nonlinear systems subject to state and control *** special contractive constraints on tracking errors and terminal constraints are embedded into the tracking nonlinear MPC ***,recursive feasibility and closed-loop convergence of the tracking MPC are guaranteed in the presence of piece-wise references and constraints by deriving some sufficient ***,the local optimality of the tracking MPC is achieved for unreachable output reference *** comparing to traditional tracking MPC,the simulation experiment of a thermal system is used to demonstrate the acceleration ability and the effectiveness of the tracking MPC scheme proposed here.

关键词： Model predictive control Nonlinear systems Constrained control Tracking control Thermal systems

Two Congruent Semantics for Prolog with CUT

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Journal of Computer Science & Technology 1990年第1期5卷 82-91页

作者：朱明远 Beijing institute of System engineering

The development of a formal semantics for a given programming language can proceed in several stages. At each stage we give an alternative semantic definition of the language, and each definition embodies successively more and more implementation details. Then we formulate and prove at each stage the congruence conditions between successive definitions in the sequence. This paper presents two formal semantics for Prolog with “cut” and shows the congruence condition between them.

关键词： ENVI Prolog Two Congruent Semantics for Prolog with CUT

Compositions and Distributions of Secondary Organic Aerosols and Their Tracers over the Pearl River Estuary Region Influenced by Continental and Marine Air Masses

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Advances in Atmospheric Sciences 2025年第4期42卷 682-696页

作者： Zhenhao LING Junlin HUANG Liqing WU Yee Jun THAM Guizhen FANG Bing WU Lili MING Xuemei WANG Xiang DING School of Atmospheric Sciences Sun Yat-sen UniversityKey Laboratory of Tropical Atmosphere-Ocean SystemMinistry of Educationand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiChina College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiangChina School of Marine Sciences Sun Yat-sen UniversityZhuhaiChina Technical Center of Gongbei Customs District of China ZhuhaiChina College of Environment and Climate Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental QualityJinan UniversityGuangzhouChina Guangzhou institute of Geochemistry Chinese Academy of SciencesGuangzhouChina

The compositions and distributions of monoterpenes,isoprene,aromatics and sesquiterpene SOA tracers(SOAM,SOAI,SOAA and SOAS,respectively)at an island site(Da Wan Shan Island,DWS)were investigated in the context of the influence of continental and marine air masses over the Pearl River Estuary(PRE)region in winter *** sum concentration of SOA tracers was 6.2–132.8 ng m^(−3),with SOAM and SOAI as the main components in both continental(scenarios A1 and A2)and marine air masses(scenario A3),as well as their combination(scenario A4).The highest and lowest levels of SOAM were observed in A1 and A3,respectively,which were mainly related to the variations in meteorological conditions,precursor concentrations,and the degree of photochemical *** MBTCA/HGA(3-methyl-1,2,3-butanetricarboxylic acid/3-hydroxyglutaric acid)ratios suggested a less significant contribution fromα-pinene to *** variations of SOAI in the different scenarios were associated with differences in relative humidity,particle acidity,and isoprene/NOx *** respective highest and lowest concentrations of aromatics SOA tracers in A1 and A3 revealed the influence of anthropogenic precursors from upwind continental areas,which was confirmed by the correlation among biogenic and anthropogenic *** results of the tracer-based-method suggested dominant contributions of SOAs from aromatics and monoterpenes,with the highest concentrations in A1.A WRF-Chem simulation revealed that the SOAs from the above precursors only contributed 12%–25%to the total SOA at DWS,while the spatial distributions of SOAs further highlighted that the abundance of SOAs over the PRE region in winter is highly associated with air masses transported from upwind continental areas.

关键词： secondary organic aerosols tracers continental and marine air masses Pearl River Estuary region

Effects of drive imbalance on the particle emission from a Bose-Einstein condensate in a one-dimensional lattice

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Chinese Physics B 2024年第3期33卷 238-243页

作者：赖龙泉李照 School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Electronic engineering Chengdu Technological UniversityChengdu 611730China

Time-periodic driving has been an effective tool in the field of nonequilibrium quantum dynamics,which enables precise control of the particle *** investigate the collective emission of particles from a Bose-Einstein condensate in a one-dimensional lattice with periodic drives that are separate in modulation amplitudes and relative *** addition to the enhancement of particle emission,we find that amplitude imbalances lead to energy shift and band broadening,while typical relative phases may give rise to similar *** results offer insights into the specific manipulations of nonequilibrium quantum systems with tone-varying drives.

关键词： Bose-Einstein condensate particle emission periodic drive

Seismic performance evaluation of a self-centering precast reinforced concrete frame structure

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Earthquake engineering and engineering Vibration 2021年第4期20卷 943-968页

作者： Mao Chenxi Wang Zhenying Key Laboratory of Earthquake engineering and engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China School of Civil engineering Harbin Institute of TechnologyHarbin 150090China

The seismic performance of a five-story,four-bay,self-centering precast reinforced concrete frame(SC-RCF),which was redesigned using the direct displacement-based design method,was analytically *** analytical model of the overall structure was developed in *** multi-spring contact element was adopted to simulate gap open-close behavior at connection *** limit states of external mild steel dampers and unbonded post-tensioning strands were *** pushover analyses were performed up to the roof drift of 10%.The nonlinear dynamic responses under four groups of ground motions(with different fault distances and site conditions)at six hazard levels(from the service to the very rare earthquake(VRE))were *** dynamic analyses were implemented to quantify the structural collapse *** results showed that the structural responses of SC-RCF were satisfactory under all levels of *** collapse safety of the structure under earthquakes up to VRE1 was adequate,while the structure would collapse to a large extent under VRE2 and VRE3.

关键词： self-centering system precast RC frame unbonded post-tensioning incremental dynamic analysis collapse fragility

High efficiency Polar coding key reconciliation scheme in wireless channel

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The Journal of China Universities of Posts and telecommunications 2019年第3期26卷 50-55页

作者： Zhang Xiaotian Zhao Shengmei institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China

Recently, physical layer security in wireless communication system attracts much attention, and the reconciliation protocol plays an important role in the final secure key distillation, since the secret keys extracted from the realistic characteristics of the wireless channel may not be the same between the transmitter and legitimate receiver. A high efficiency Polar coding key reconciliation scheme is proposed in the paper to correct these errors. In the scheme, the transmitter generates a random stream with the known frozen bits and positions. After that, the transmitter encodes the random bit stream to a code stream by Polar encoding and sends the corrupted version of the code stream and the secret keys to the legitimate receiver. The receiver decodes the received stream with Polar successive cancellation decoding algorithm. With Polar encoding, the receiver obtains a random bit stream, and achieves the final secure key by XOR operator. The results show that the proposed scheme has a higher efficiency and a lower computational complexity, along with a high success rate. The consistency of the keys is very good after the reconciliation.

关键词： security of physical layer Polar coding channel characteristics computational complexity success rate

Performance evaluation of laponite as a mud-making material for drilling fluids

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Petroleum Science 2019年第4期16卷 890-900页

作者： Zheng-Qiang Xiong Xiao-Dong Li Fan Fu Yan-Ning Li Beijing institute of Exploration engineering

In this study, laponite was tested as a mud-making material for drilling fluids. Laponite is a synthetic smectite clay with a structure and composition closely resembling the natural clay mineral hectorite. Commercially available laponite was characterized by X-ray di ractometry, scanning electron microscopy and infrared spectrometry. Its dispersibility, salt resistance and high-temperature resistance were evaluated. The results showed that laponite possessed superior cation exchange capacity(140.4 mmol/100 g) with interlayer cations of Na^+ and Li^+. Laponite could easily be dispersed in water to yield increased viscosity with no influence from hydration time or temperature. On the other hand, laponite dispersions displayed an excellent heat resistance, with invariant apparent viscosity at high temperatures. For instance, the apparent viscosity of the2 wt% laponite dispersion underwent changes between 22 and 24 mPa s after hot rolling at 180–240 °C for 16 h. Compared to existing mud-making materials, laponite exhibited better mud-making properties. Furthermore, laponite revealed good compatibility with other additives, and the water-based drilling fluids prepared with laponite as mud-making material showed an excellent stability at elevated temperatures and superior performance–cost ratios. Overall, these findings indicated that laponite had an excellent dispersibility at high temperatures and hence would have promising applications as high-temperature mud-making material for preparing water-based drilling fluids designed for ultra-high-temperature environments.

关键词： Laponite Mud-making material Dispersibility High-temperature tolerance Ultra-high-temperature water-based drilling fluids

Multicolor emission from lanthanide ions doped lead-free Cs_(3)Sb_(2)Cl_(9) perovskite nanocrystals

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Journal of Rare Earths 2024年第5期42卷 940-946,I0005页

作者： He Shao Lifang Li Xiufeng Wu Lin Xu Biao Dong Donglei Zhou Xue Bai Hongwei Song State Key Laboratory of Organic Electronics and Information Displays&institute of Advanced Materials College of Materials Science and EngineeringNanjing University of Posts&TelecommunicationsNanjing210023China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and Engineering Jilin UniversityChangchun130012China

The toxicity of lead ions has become the severe challenge for the all-inorganic lead halide p erovskite materials,although some works have rep orted the lead-free perovskite nanocrystals(NCs),the photoluminescence quantum yield(PLQY)of these materials is still ***,because the halogen ions can be easily exchanged,the controllable multicolor emission in perovskite NCs is difficult to realize in current *** this work,we introduced lanthanide ions into lead-free Cs_(3)Sb_(2)Cl_(9) perovskite *** from the energy transfer between Cs_(3)Sb_(2)Cl_(9) perovskite NC host and lanthanide ions,the multicolor emission was *** on controlling the doping concentration of Tb^(3+)and Eu^(3+)ions,the white light emission under UV excitation would be turned easily in the Tb^(3+)/Eu^(3+)codoped *** addition,efficient energy transfer from perovskite NCs to Tb^(3+)or Eu^(3+)ions is beneficial to improving the optical properties of lead-free perovskite NCs,resulting in maximum PLQYs of red,green and white light emission of 22.6%,19.7%and 28.5%,***,a white light emitting device(WLED)was fabricated with a power efficiency of 18.5 lm/W,which presents the Commission Internationale de l'Eclairage(CIE)of(0.33,0.35).

关键词： Perovskite nanocrystals Lead free Lanthanide ions Energy transfer White light emitting device Rare earths