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Efficient Early Termination Strategy for LDPC Codes in GPS Systems

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Journal of Harbin Institute of Technology(New Series) 2013年第6期20卷 118-122页

作者： Feng Wang jin-hai li jin-hai Sun Yue-Peng Yan Institute of Microelectronics of Chinese Academy of Sciences

By exploiting the structural features of L1C messages,a novel Early Termination( ET) strategy is proposed to speed up the decoding of low-density parity-check( LDPC) codes in the GPS system. The proposed strategy is based on the cyclic redundancy check( CRC) of the messages in the subframes 2 and 3. The simulation results show that average number of iterations of the proposed strategy is less than that of the standard ET strategy,with nearly no degradation in decoding performance. Besides,the proposed ET strategy can be efficiently implemented in a sequential or parallel manner. Thus,the proposed ET strategy is attractive for practical purposes.

关键词： GPS system low-density parity-check (LDPC) codes early termination (ET) strategy cyclic redundancy check (CRC)CLC number:TN911.22 Document code:AArticle ID:1005-9113(2013)06-0118-05

Thermoelectric properties of Al substituted misfit cobaltite Ca_3(Co_(1-x)Al_x)_4O_9 at low temperature

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International Journal of Minerals,Metallurgy and Materials 2014年第7期21卷 720-725页

作者： Yi liu Hong-mei Chen jin-lian Hu Xu-bing Tang hai-jin li Wei Wang School of Mathematics and Physics Anhui University of Technology Institute of Optoelectronic Information Materials and Technologies Anhui University of Technology School of Materials Science & Engineering Anhui University of Technology

Thermoelectric properties of Al substituted compounds Ca3（Co1-xAlx）4O9 （x=0, 0.03, 0.05）, prepared by a sol-gel process, have been investigated in the temperature range 305-20 K. The results indicate that after Al substitution for Co in Ca3（Co1-xAlx）4O9, the direct current electrical resistivity and thermopower increase due to the reduction of carrier concentration. Experiments show that Al substitution results in decreased lattice thermal conductivity. The figure of merit of temperature behavior suggests that Ca3（Co0.97Al0.03）4O9 would be a promising candidate thermoelectric material for high-temperature thermoelectric application.

关键词： transition metal oxides sol-gel process thermoelectricity electrical properties substitution

Study on superprism effect in the multilayer optical thin film stack

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光学精密工程 2005年第4期13卷 454-458页

作者： SUN Xue-zheng GU Pei-fu CHEN hai-xing jin Bo li hai-feng liU Xu State Key Laboratory of Modern Optical Instrumentations Zhejiang University Hangzhou 310027 China

Researches show that multilayer optical thin film stack can exhibit superprism effect due to their large abnormal dispersions. We investigated and simulated this effect numerically in a 1-D non-periodic film structure-Fabry-Perot filters (FPF), which possess drastic change in phase and large group delay around wavelength of peak transmittance, and fabricated this device to realize remarkable superprism effect. We tested experimentally with the maximum spatial separation shift up to 65 μm, and the experimental result is in good agreement with the theory. Compared with the traditional prism, the total thickness of our structure is only 3.3 μm, and our prism shows a stronger angular resolution of 1.8°/nm.

关键词：薄膜涂覆技术多层膜 FPF

2D-MOF/2D-MOF heterojunctions with strong hetero-interface interaction for enhanced photocatalytic hydrogen evolution

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Rare Metals 2023年第12期42卷 3993-4004页

作者： Yan Ma Hui-Xue Fang Rong Chen Qian Chen Sheng-Jun liu Kui Zhang hai-jin li School of Materials Science and Engineering Anhui University of TechnologyMa'anshan 243032China School of Chemistry and Chemical Engineering Anhui University of TechnologyMa'anshan 243032China School of Energy and Environment Anhui University of TechnologyMa'anshan 243002China

Metal organic framework(MOF) shows great potential in the research field of photocatalysis,and it is a big challenge to achieve efficient photocatalytic *** this work,we have successfully grown two-dimensional MOF(2D-MOF) nanosheets on 2D-MOF nanosheets for the first time using a homometallic nodal strategy,and successfully prepared ultrathin nanosheets with tightly bound 2D/2D heterojunctions.2D Ni-BDC nanosheets were used as carriers to grow 2D Ni-TCPP nanosheets on top of ***-TCPP has a high light absorption capacity,thus extending the light absorption range of 2D/2D *** tight coupling of the heterojunction effectively shortens the electron transfer distance,promotes the separation of interracial charges,and improves the photocatalytic ***,Ni-BDC/Ni-TCPP-3can achieve to a hydrogen production rate of428.0 μmol·g^(-1),approximately 5.75 times higher than NiBDC and 5.24 times higher than Ni-TCPP,***,2D-MOF/2D-MOF heterojunctions provide a promising strategy for enhancing photocatalytic performance through rational heterostructure design with homometallic node strategy.

关键词： Two-dimensional metal organic framework(2D MOF) Homometallic node strategy Heterojunction Photocatalytic

A contribution to the study of the modified Marschalk reaction:Hydroxymethylation of 6,8-O-dimethyl emodin

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Chinese Chemical Letters 2010年第5期21卷 568-571页

作者： hai Shan jin,li Ming Zhao School of Chemistry and Chemical Engineering,Xuzhou Normal University,Xuzhou 221116,China School of Chemistry and Chemical Engineering Xuzhou Normal University Xuzhou 221116 China

Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk *** influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was *** results showed that a relatively dilute reaction solution facilitated the generation of the desired 2-hydromethyl product,while the thick reaction solution benefited the generation of the methylated quinizarins.

关键词： Marschalk reaction Hydroxymethylation Emodin Antitumor activity

Cosmic ray electron spectrum due to the dispersion of injection spectrum

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Chinese Physics C 2018年第7期42卷 89-93页

作者： Tian-Lu Chen Wei liu Qi Gao Mao-Yuan liu hai-jin li Danzengluobu Ying Shi School of Physics and Technology Wuhan University Wuhan 430072 China Physics Department of the Science School Tibet University Lhasa 850000 China Key Laboratory of Cosmic Rays（Tibet University） Ministry of Education Lhasa 850000 China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The cosmic-ray total electron spectrum （electrons plus positrons） has been measured precisely up to TeV energies, with more interesting features found. Exhaustive analyses of the electron spectrum strongly support a spectral hardening above 100 GeV, rather than a featureless single power-law, which is confirmed by the most recent observations. Meanwhile, the measurements of the DAMPE satellite have verified the presence of a knee-like structure around 1 TeV in the electron spectrum, resembling the cosmic-ray knee. In this paper, we establish a physical model in which the observed electron spectrum is composed of a superposition of CR sources with various spectral indices and high-energy cutoffs. The dispersion of the power index is assumed to be Gaussian, while the cutoff energy Ec follows a power-law distribution. These simple ideas can account naturally for both the hundred-GeV excess and the TeV spectral break.

关键词： electron spectrum cosmic rays source DAMPE

Endoscopic dacryocystorhinostomy in acute dacryocystitis:a multicenter study in China

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1689-1695页

作者： Bang-Xun Mao Yao-Hua Wang Zhen-Kai liu Ning-Yu An hai-li jin Ming-ling Wang Wen-Can Wu Bo Yu Department of Ophthalmology Central Hospital of LishuiThe Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina Department of Orbital Disease and Ophthalmic Tumor Affiliated Eye Hospital of Nanchang UniversityNanchang 330000Jiangxi ProvinceChina Department of Ophthalmology Renmin Hospital of ShiyanShiyan 442000Hubei ProvinceChina Eye Hospital of Ningxia Yinchuan 750000Ningxia Hui Autonomous RegionChina Eye Hospital of Wuhu City Wuhu 241000Anhui ProvinceChina Department of Ophthalmology Baoan Central Hospital of ShenzhenShenzhen 518000Guangdong ProvinceChina Department of Orbital and Oculoplastic Surgery Eye Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

AIM:To repor t the clinical profile,endoscopic dacryocystorhinostomy(En-DCR)management,and acute dacryocystitis(AD)outcomes in ***:Clinical data of 554 adult AD patients(554 eyes)who presented in 7 tertiary eye care centers for 10y from Jan 2010 to Mar 2020 were retrospectively *** profile,En-DCR management,and outcomes of all cases were *** anatomical and functional success were evaluated for 12mo ***:The analysis included 149 males and 368 females with a median age of 55.2y(range:18-84y).There were 459 eyes with a history of epiphora or purulent *** time between a symptom of lacrimal duct obstruction and acute onset was 1 to 540(66.1±58.2)***-nine eyes had a history of the previous acute ***-four eyes developed a cutaneous fistula,while 11 eyes had post septal cellulitis ***-DCR with an anatomical success of 91.7%and functional success of 90.1%.The success rate of the patients with a history of acute episodes and the preoperative fistula was lower than the overall success ***:En-DCR can be performed during an acute episode in AD with a success rate of over 90%.

关键词： acute dacryocystitis endoscopic dacryocystorhinostomy lacrimal sac

Efficacy and safety of triple-antiplatelet therapy after percutaneous coronary intervention： a meta-analysis

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Chinese Medical Journal 2013年第9期126卷 1750-1754页

作者： ZHANG Yong TANG hai-qin li jin FU Zhao-xin Department of Geriatrics First Affiliated Hospital of Anhui Medical University Hefei Anhui 230022 China

Background The combination of cilostazol, aspirin and clopidogrel （triple antiplatelet therapy, TAT） after a percutaneous coronary intervention has been used as an alternative therapy. We performed a meta-analysis to evaluate the efficacy and safety of TAT for patients after percutaneous coronary intervention （PCI）. Methods We systematically searched Pubmed, Embase and Web of Science databases to identify all randomized controlled trials （RCTs） that compared dual antiplatelet therapy （DAT） with and without cilostazol after PCI. All analyses were conducted using Review Manager 5.0. Results The final analysis consisted of 4474 patients from ten studies. The combined results suggested that there was a lower risk of cardiac death （relative risk （RR）=0.55, 95% confidence interval （Cl）： 0.31-0.98, P 〈0.05） and major adverse cardiac events （MACEs）（RR=0.63, 95% Cl： 0.54-0.74, P 〈0.05） in patients treated with TAT as compared to those with DAT follow-ups after six months to one year; no significant difference was observed in bleeding and non-fatal myocardial infarction （MI）（RR=1.14, 95% Cl： 0.80-1.64, P 〉0.055 RR=0.87, 95% Cl： 0.42-1.83, P 〉0.05）. However, the rate of adverse drug reaction was higher in patients receiving TAT than in patients receiving DAT （RR=2.21, 95% Cl： 1.84-2.66, P 〈0.05）. Moreover, there was a lower risk of stent thrombosis in patients treated with TAT as compared to those treated with DAT （RR=0.44, 95% Cl： 0.21-0.94, P 〈0.05）. The TAT group had a reduced risk of target lesion revascularization （TLR）（RR=0.60, 95% Cl： 0.43-0.82, P=-0.001） and target vessel revascularization （TVR） than the DAT group （RR=0.56, 95% Cl： 0.45-0.71, P 〈0.05）. The number of MACEs was lower for patients in the TAT group than in the DAT group with diabetes mellitus sub-analysis （RR=0.41, 95% Cl： 0.28-0.61, P 〈0.05）. But no significant difference was observed between the two groups regarding MACEs in patients with drug-eluting stent implantations （RR=0.82, 95% Cl： 0.65-1.03, P

关键词： triple antiplatelet therapy dual antiplatelet therapy percutaneous coronary intervention meta-analysis

Research on Cold Chain Logistics Distribution Routing Algorithm Model Based on Customer Satisfaction

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Research on Cold Chain Logistics Distribution Routing Algori...