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Computationally efficient channel estimation and inter-carrier interference suppression for OFDM communication systems

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 17-23页

作者： CAI Meng,ZHANG Ke-feng,ZOU Xue-cheng,liu Hao School of Electronics of Science and Technology,Huazhong University of Science and Technology,Wuhan 430074,China School of Electronics of Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

This article puts forward a novel channel estimation and inter-carrier interference（ICI） suppression method for time-varying orthogonal frequency division multiplexing（OFDM） *** proposed adaptive finite impulse response（FIR） filter utilizes the time domain correlation of the *** on the one order auto-regressive（AR） model,a modified Kalman filter is exploited to track the channel *** solving the Yule-Walker equation,the coefficient of the AR process can be obtained from zero order Bessel ***,when the channel is assumed not perfectly known,the above criterion will lead to an impractical *** deal with it,the coefficient of the AR process is taken as a *** a new state space model is deduced and *** results show that the proposed method can work effectively at the speed of 144 km/h with a phase noise of -85 dBc/Hz at 100 kHz *** proposed method yields an improvement bit error rate（BER） compared with three of the existing algorithms with much lower complexity.

关键词： channel estimation OFDM ICI phase noise Kalman filter

Xi'an's old streets in modern times

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中国周刊 2003年第10期 13-15页

作者： cheng feng and liu Daoxuan

Old streets are disappearingXi’an, the capital of Shaanxi province, is an important link in China’s northwest to southwest transportation network. Xi’an, also called “Chang’an” in ancient times, was China’s capital during the Zhou (11th century - 256 BC), Qin (221 - 206 BC), Han (206 BC - 220 AD), Tang (618 - 907) and nine other dynas-

关键词： in with as for be Xi’an’s old streets in modern times were of Bell have

Induction of Bladder Lesion by Terephthalic Acid and Its Mechanism

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Biomedical and Environmental Sciences 2005年第4期18卷 211-219页

作者： GUI-DONG DAI LUN-BIAO CUI LING SONG REN-ZHEN ZHAO JIAN-feng cheng MEI-XIA liu JIAN-WEI ZHOU HANG XIAO XIN-RU WANG Institute of Toxicology Nanfing Medical University Nanfing 210029 Jiangsu China

To provide more information for rational evaluation of potential risks of terephthalic acid （TPA）, we studied the effects of TPA on rats＇ bladders in 90 days after TPA exposure. Methods Sprague Dawley rats were subdivided into five groups, ingesting 0 %, 0.04 %, 0.2 %, 1%, and 5 % TPA respectively for a sub-chronic feeding study lasting for 90 days. Urine, serum and samples of brain, liver, lung, kidney, bladder, etc. were collected and analyzed. Results TPA ingesting decreased the value of urinary pH, and increased the contents of Ca^2＋, Zn^2＋, Mg^2＋, Na^＋, K^＋ in urine. The volume of 24 h urine was significantly increased in male rats in the 1% and 5 % TPA groups. Urinary white sediment was found in both sexes, and its formation in male rats seemed more susceptible than that in female rats. Alpha 2u-globulin （AUG） in serum and urine of male rats was markedly increased in a dose-dependent manner. Fifteen cases of hyperplasia （simple or atypical） were determined in the 5 % TPA ingesting group, 14/52 in male rats and 1/23 in female rats. Among them 3 male rats had no stone or calculus. Those with either bladder stones or hyperplasia were accompanied with urinary white sediments. Conclusion White sediment accompanied with elevated urine AUG is the basis of TPA induced urolith formation, and is also associated with TPA induced bladder epithelial cell proliferation. It can act as an early biomarker for the potential toxic effect of TPA.

关键词： Terephthalic acid Bladder Uroliths Hyperplasia Sediment Alpha 2μ-globulin

The large-scale modular BGO detection array(LAMBDA)design and test

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Nuclear Science and Techniques 2024年第11期35卷 228-236页

作者： Yao-De Sheng Lu-Yang Song Jun Su Shi-Lun Jin Fei Lu Yang-Ping Shen Jun-feng Chen Li-Yong Zhang Jian-Jun He Xin-Yue Li Hong-Na liu feng-Shou Zhang Meng-Lin Qiu Shen Lin Hao Zhang Luo-Huan Wang Zi-Ming Li Yin-Ji Chen Xin-Zhi Jiang Xin Chen Zhi-Lin Shen feng-cheng liu Zhi-Wei Qin Lin Wang Yi-Tong Huang Xiang Li Si-Ze Chen You-Bao Wang Zhi-Hong Li Bing Guo Wei-Ping liu Key Laboratory of Beam Technology of Ministry of Education School of Physics and AstronomyBeijing Normal UniversityBeijing 100875China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 201800China Key Laboratory of Nuclear Physics and Ion‑Beam Application(MoE) Institute of Modern PhysicsFudan University200433 ShanghaiChina School of Mathematics and Physics Handan UniversityHandan 056005China Institute of Nuclear Energy Safety Technology Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Department of Physics Southern University of Science and TechnologyShenzhen 518055China

Total absorption gamma-ray spectroscopy(TAGS)is a powerful tool for measuring complexγ transitions,which has been effectively applied to the study of reactor decay *** paper presents the design of a new TAGS detector,the large-scale modular BGO detection array(LAMBDA),tailored for measuringβ-decay intensity distributions of fission *** modular design allows the LAMBDA detectors to be assembled in various *** final version of LAMBDA consists of 102 identical 60 mm×60 mm×120 mm BGO crystals and exhibits a high full-energy peak efficiency exceeding 80%at 0.5∼8 MeV based on a Monte Carlo ***,approximately half of the LAMBDA modules have been *** usingγ-ray sources and nuclear reactions demonstrated favorable energy resolution,energy linearity,and efficiency uniformity across the ***-eight modules have been integrated into the prototype *** capability of LAMBDA-I inβ-delayedγ-decay experiments was evaluated by commissioning measurements using the ^(152)Eu source.

关键词： Total absorption gamma-ray spectroscopy Reactor decay heat Beta-decay BGO detector array LAMBDA

Pancreatic stent improves the success rate of needle-knife papillotomy in patients with difficult biliary cannulation

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World Journal of Gastroenterology 2025年第1期31卷 58-67页

作者： Mu-Hsien Lee cheng-Hui Lin Chi-Huan Wu Yung-Kuan Tsou Kai-feng Sung Sheng-Fu Wang Nai-Jen liu Department of Gastroenterology and Hepatology Chang Gung Memorial Hospital and Chang Gung University College of MedicineTaoyuan 33305Taiwan School of Medicine Chang Gung UniversityTaoyuan 33305Taiwan

BACKGROUND Needle-knife precut papillotomy(NKP)is typically performed ***,it remains unclear whether pancreatic stent(PS)placement can improve the outcomes of *** To explore whether PS placement improves the success rate of NKP in patients with difficult biliary *** This single-center retrospective study included 190 patients who underwent NKP between January 2017 and December 2021 after failed conventional biliary *** cases with incidental pancreatic duct cannulation during conventional biliary cannulation,the decision for pre-NKP PS placement was made at the endoscopist's *** primary outcome was the difference in the NKP success rate between patients with and without PS placement;the secondary outcome was the adverse event *** Among the 190 participants,82 received pre-NKP PS(PS-NKP group)whereas 108 did not[freehand or freehand NKP(FH-NKP)group].Post-NKP selective biliary cannulation was successful in 167(87.9%)patients,and the PS-NKP had a significantly higher success rate than the FH-NKP group(93.9%vs 83.3%,P=0.027).The overall adverse event rates were 7.3%and 11.1%in the PS-NKP and FH-NKP groups,respectively(P=0.493).A periampullary diverticulum(PAD)and significant intraoperative bleeding during NKP were independently associated with NKP failure;however,a pre-NKP PS was the only predictor of NKP *** the 44 participants with PADs,the PS-NKP group had a non-significantly higher NKP success rate than the FH-NKP group(87.5%and 65%,respectively;P=0.076).CONCLUSION PS significantly improved the success rate of NKP in patients with difficult biliary cannulation.

关键词： Difficult biliary cannulation Endoscopic retrograde cholangiopancreatography Needle-knife papillotomy Pancreatic stent Selective biliary cannulation

Ru doping triggering reconstruction of cobalt phosphide for coupling glycerol electrooxidation with seawater electrolysis

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Journal of Energy Chemistry 2025年第1期100卷 317-326页

作者： Binglu Deng Jie Shen Jinxing Lu Chuqiang Huang Zhuoyuan Chen feng Peng Yunpeng liu School of Materials Science and Hydrogen Energy Foshan University School of Chemistry and Chemical Engineering Guangzhou University Guangdong Key Laboratory for Hydrogen Energy Technologies

Seawater electrolysis is a promising approach for sustainable energy without relying on precious ***,the large-scale seawater electrolysis is hindered by low catalytic efficiency and severe anode corrosion caused by the harmful *** contrast to the oxygen evolution reaction （OER）and chlorin ion oxidation reaction （ClOR）,glycerol oxidation reaction （GOR） is more thermodynamically and kinetically favorable ***,a Ru doping cobalt phosphide （Ru-CoP2） is proposed as a robust bifunctional electrocatalyst for seawater electrolysis and GOR,for the concurrent productions of hydrogen and value-added *** in situ and ex situ characterization analyses demonstrated that Ru doping featured in the dynamic reconstruction process from Ru-CoP2to Ru-CoOOH,accounting for the superior GOR *** coupling GOR with hydrogen evolution was realized by employing Ru-CoP2as both anode and cathode,requiring only a low voltage of 1.43 V at 100 mA cm-2,which was 250 m V lower than that in alkaline *** work guides the design of bifunctional electrocatalysts for energy-efficient seawater electrolysis coupled with biomass resource upcycling.

关键词： Glycerol electrooxidation Hydrogen evolution Ru doping Cobalt phosphide Bifunctional electrocatalysts

Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei Xiong Xuan Ye Hongzhang cheng Xiaoming liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

基于Brutsaert模型的黄土高原蒸发规律研究

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黑龙江水利科技 2020年第8期48卷 13-16页

作者：冯刘成新疆维吾尔自治区塔里木河流域干流管理局新疆阿拉尔843300

文章采用Brutsaert所研究的多项式形式模型,研究时间跨度为1951年至2015年,对黄土高原地区的蒸发规律进行模拟。按照各个小流域和不同的数据站点,分年份来计算整个黄土高原区域近50a的蒸发趋势。结果表示,黄土高原东部地区的蒸发量呈现... 详细信息

文章采用Brutsaert所研究的多项式形式模型,研究时间跨度为1951年至2015年,对黄土高原地区的蒸发规律进行模拟。按照各个小流域和不同的数据站点,分年份来计算整个黄土高原区域近50a的蒸发趋势。结果表示,黄土高原东部地区的蒸发量呈现出减少的趋势,中部与西部地区没有出现增长。太阳辐射时长的变化是蒸发量变化最为重要的影响因素,温度和风力的变化是次要因素。

关键词：蒸散发黄土高原 Brutsaert模型

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie liu Changqing Xu Da-Jian Wu Ying cheng Xiao-Jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure