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Design of coordinator to eliminate redundant local retransmission in wireless networks

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 63-69页

作者： FANG Xi wang Jun wang Yong jiang feng Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

Owing to limited bandwidth, high bit error rate, and bursty error in the wireless environment, the performance of the transmission control protocol （TCP） degrades greatly in wireless networks. Up to now, many researchers have contributed greatly to the wireless TCP field. However, in most of their works, the wireless TCP module usually works in the TCP layer and has no idea of the actual time of the packet transmission, which is determined by the Scheduler in the media access control （MAC） layer, and this will bring the inaccuracy to the local retransmission fimeout and induce the redundant local retransmission. In this article, a coordinator is introduced into the base-station （BS）, which can provide efficient cooperation between the TCP module and the scheduler module. On the bais of the performance analysis and simulation results, the proposed method is shown to eliminate redundant local retransmission, increase throughput, and improve TCP-level fairness in wireless networks. Moreover, this scheme is orthogonal to those existing wireless TCP schemes, thus it can give great compatibility to the current networks, and further enhance the performance of TCP under the condition that the performance improvement benefiting from the existing approaches will not be affected.

关键词： TCP wireless network coordinator scheduling throughput fairness

Structured trajectory planning of collision-free lane change using the vehicle-driver integration data

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Science China(Technological Sciences) 2016年第5期59卷 825-831页

作者： wang jiang feng ZHANG Qian ZHANG Zhi Qi YAN Xue Dong MOE Key Laboratory for Urban Transportation Complex Systems Theory and Technology Beijing Jiaotong University

In this paper, the structured trajectory planning of lane change in collision-free road environment is studied and validated using the vehicle-driver integration data, and a new trajectory planning model for lane change is proposed based on linear offset and sine function to balance driver comfort and vehicle dynamics. The trajectory curvature of the proposed model is continuous without mutation, and the zero-based curvature at the starting and end points during lane change assures the motion direction of end points in parallel with the lane line. The field experiment are designed to collect the vehicle-driver integration data, such as steering angle, brake pedal angel and accelerator pedal angel. The correction Correlation analysis of lane-changing maneuver and influencing variables is conducted to obtain the significant variables that can be used to calibrate and test the proposed model. The results demonstrate that vehicle velocity and Y-axis acceleration have significant effects on the lane-changing maneuver, so that the model recalibrated by the samples of different velocity ranges and Y-axis accelerations has better fitted performance compared with the model calibrated by the sample trajectory. In addition, the proposed model presents a decreasing tendency of the lane change trajectory fitted MAE with the increase of time span of calibrating samples at the starting stage.

关键词： intelligent vehicle lane change trajectory planning vehicle-driver integration

汽轮机热力性能智能评估与劣化分析系统研究进展

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汽轮机技术 2024年第4期66卷 241-245页

作者：李铭张海军王梦轩程梓洋程上方王江峰国能长源汉川发电有限公司汉川431614 西安交通大学西安710049

随着火力发电行业的不断发展,汽轮机作为核心设备之一,其高效可靠地运行对于电厂的稳定供电至关重要。故障预测与诊断技术能够提前评估机组实际运行过程中性能劣化甚至故障的原因,是保证大型汽轮机组安全、稳定运行的重要技术之一。从... 详细信息

随着火力发电行业的不断发展,汽轮机作为核心设备之一,其高效可靠地运行对于电厂的稳定供电至关重要。故障预测与诊断技术能够提前评估机组实际运行过程中性能劣化甚至故障的原因,是保证大型汽轮机组安全、稳定运行的重要技术之一。从经验知识、数学模型和数据驱动3个方面介绍了故障预测与诊断技术的国内外研究现状。针对汽轮发电机组热力性能评估和劣化趋势分析问题,总结了智能预测诊断技术未来的发展趋势,为火电汽轮机组高效灵活安全运行提供参考。

关键词：汽轮机故障预测与诊断劣化趋势机器学习

A novel protein refolding method integrating ion exchange chromatography with artificial molecular chaperone

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Chinese Chemical Letters 2008年第5期19卷 595-598页

作者： Qin Ming Zhang Chao Zhan wang jiang feng Liu Li Li wang Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Institute of Modern Separation Science Key Laboratory of Separation Science in Shanxi Province Department of Chemistry Northwest University Xi＇an 710069 China

Artificial molecular chaperone （AMC） and ion exchange chromatography （IEC） were integrated, thus a new refolding method, artificial molecular chaperone-ion exchange chromatography （AMC-IEC） was developed. Compared with AMC and IEC, the activity recovery of lysozyme obtained by AMC-IEC was much higher in the investigated range of initial protein concentrations, and the results show that AMC-IEC is very efficient for protein refolding at high concentrations. When the initial concentration of lysozyme is 180 mg/mL, its activity recovery obtained by AMC-IEC is still as high as 76.6%, while the activity recoveries obtained by AMC and IEC are 45.6% and 42.4%, respectively.

关键词： Artificial molecular chaperone Ion exchange chromatography Protein refolding Lysozyme Protein folding liquid chromatography

Fabrication of Two-dimensional Monolayer and One-dimensional Wire of Zn-tetra-[3,5-di-t-butylphenyl]-porphyrin on Cu(100) Surface

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Chinese Journal of Structural Chemistry 2006年第8期25卷 992-996页

作者： QIAN Li-Ping wang Xian XU Di wang Zhou-feng jiang Zhong-Jie DENG Wen-Li College of Materials Science and Engineering South China University of Technology Guangzhou 510640 China

We describe in this paper the fabrication of two- and one-dimensional nanostructures with organic molecular beam epitaxy （OMBE） principle based on controlled selfassembly by using adsorbate-substrate and intennolecular interactions that are important in molecular fabrication. Cu（100） single crystal was used as substrate in fabricating molecular nanostructures. Scanning tunneling microscopy （STM） experiments confirmed that Zn-tetra- [3,5-di-t-butylphenyl]porphyrin-molecules can be used to fabricate both monolayer and molecular wire on Cu（100） surface simultaneously, and the latter is arranged on the terrace edges. We herein briefly discuss the selectivity in terms of a mechanism in which the highest occupied and lowest unoccupied molecular orbitals （HOMO and LUMO） of the molecules interact with the surface.

关键词： fabrication two-dimensional monolayer one-dimensional molecular wire Zn-tetra-[3,5-di-t-butylphenyl]porphyrin

Application of Bionic Technology in Marine Cruise Equipment:Research Progress and Development Trends

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Journal of Bionic Engineering 2024年第3期21卷 1117-1155页

作者： Kunhui Luo Lan Yan Zhiyi Zhu Zhongqiu wang Hongru wang feng jiang School of Electromechanical and Automation Huaqiao UniversityXiamen36102China National Local Joint Engineering Research Center for Intelligent Manufacturing Technology of Brittle Material Products Xiamen361021China Institute of Oceanographic Instrumentation Shandong Academy of SciencesQilu University of Technology(Shandong Academy of Sciences)Qingdao266100China Shandong Provincial Key Laboratory of Marine Monitoring Instrument Equipment Technology Qingdao266100China National Engineering and Technological Research Center of Marine Monitoring Equipment Qingdao266100China Institute of Manufacturing Engineering Huaqiao UniversityXiamen361021China

This article provides an overview of the application of bionic technology in marine cruising equipment,discussing its research progress and future development *** cruising is a crucial means of gaining insights into the marine environment and conducting scientific ***,conventional marine cruising equipment faces numerous challenges when dealing with complex and ever-changing marine *** technology,as a means of drawing inspiration from the structure and functions of living organisms,offers new approaches and methods to address the challenges faced by marine cruising equipment and has found widespread *** article primarily focuses on the applications and historical developments of bionic technology in propulsion methods,drag reduction,and surface *** summarizes the design principles,manufacturing techniques,and optimization methods for marine biomimetic cruising ***,this paper analyzes the achievements,challenges,and future directions of bionic technology in marine cruising *** application of bionic technology in marine cruising equipment holds vast potential for development,enabling us to better confront the challenges of marine exploration and research by drawing wisdom from nature and driving advancements in marine science.

关键词： Marine cruising equipment Bionic technology Propulsion methods Drag reduction Surface antifouling

Transient liquid phase diffusion bonding of copper alloy to stainless steel using CuMn alloys as interlayer

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中国有色金属学会会刊：英文版 2000年第3期10卷 349-352页

作者： YU Zhi shui(于治水) wang feng jiang(王凤江) LI Xiao quan(李晓泉) wang Yu(王宇) WU Ming fang(吴铭方) E China Shipbldg Inst Dept Mat Engn Zhenjiang 212003 Peoples R China

With CuMn alloy as interlayer, the transient liquid phase (TLP) diffusion bonding of Cu alloys (CuAlBe) to stainless steel (1Cr18Ni9Ti) was studied. The results show that the bonding pressure, time and temperature and the content of Mn in CuMn alloy have great effects on the strength of bonding interface; when they are 1 MPa, 40 min, 1 223 K and 30% respectively, the maximum joint strength of 487 MPa is attained. The fracture occurring at the bonding interface is a plastic one and the effect of Mn has been analyzed.

关键词： copper alloys stainless steels diffusion bonding CuMn alloys

Efficient ammonia electrosynthesis from nitrate via a three-step relay mechanism

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Science China Chemistry 2024年第1期67卷 319-320页

作者： Haifeng jiang Gao-feng Chen Haihui wang Beijing Key Laboratory for Membrane Materials and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Department of Colloid Chemistry Max-Planck Institute of Colloids and InterfacesPotsdam 14476Germany School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China

Electrocatalytically converting nitrate waste to value-added ammonia(NO3−RR)is beneficial to environmental restoration and an attractive candidate for green ammonia production[1].However,developing NO_(3)^(-)RR in an energy-saving way remains a significant challenge due to the slow kinetics inherent in multi-step electron and proton transfer,making previous investigations for NO_(3)^(-)RR generally operate at a large overpotential(<-0.2 V versus reversible hydrogen electrode(RHE))to achieve optimal efficiency and industrial current for NH3 synthesis[2].

关键词： ammonia nitrate kinetics

Do nocturnal birds use acoustic and visual cues to avoid predation by bats?

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Integrative Zoology 2024年第3期19卷 524-537页

作者： Lixin GONG Huan WU Zhiqiang wang Hui WU jiang feng Tinglei jiang Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal UniversityChangchunChina Key Laboratory of Vegetation Ecology of Education Ministry Institute of Grassland ScienceNortheast Normal UniversityChangchunChina College of Life Science Jilin Agricultural UniversityChangchunChina

Anti-predation strategies are critical to animal survival and are fundamental to deciphering predator–prey *** an important defense strategy,sensory predator detection(such as through acoustic and visual cues)enables animals to assess predation risk and execute predator-avoidance behavior;however,there are limited studies on the anti-predation behavior of nocturnal *** prey of bats provides an excellent representative system for examining the anti-predation behavior of nocturnal ***,we broadcasted different types of echolocation calls of the bird-eating bat Ia io to two wild passerine birds,namely,Zosterops japonicus and Sinosuthora webbiana,that are preyed upon by ***,and presented the birds with individual bats under different light *** results showed that both bird species were able to perceive the low-frequency audible portion of the bats’echolocation calls;however,they did not exhibit escape responses to the acoustic *** the dark and under moonlit conditions,both bird species were unable to respond to active bats at close range and the birds only exhibited evasive flight behavior when bats approached or touched *** results suggest that nocturnal passerine birds may not be able to use acoustic or visual cues to detect bats and adopt evasive maneuvers to avoid *** work suggests that bat predation pressure may not elicit primary predator-avoidance responses in nocturnal passerine *** results provide new insights into the anti-predation behavior of nocturnal animals.

关键词： anti-predation behavior nocturnal animals sensory cues sensory defenses