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Realtime robust speech communication based on iterative joint source-channel decoding and demodulation algorithm for MELP vocoder

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High Technology Letters 2010年第2期16卷 111-116页

作者：彭坦 cui Huijuan Tang kun Tsinghua National Laboratory for Information Science and Technology State Key laboratory on Microwave and Digital Communications Department of Electronic Engineering Tsinghua University Beijing 100084 P.R. China

Realtime speech communications require high efficient compression algorithms to encode speech signals. As the compressed speech parameters are highly sensitive to transmission errors, robust source and channel decoding and demodulation schemes are both important and of practical use. In this paper, an it- erative joint souree-channel decoding and demodulation algorithm is proposed for mixed excited linear pre- diction （MELP） vocoder by both exploiting the residual redundancy and passing soft information through- out the receiver while introducing systematic global iteration process to further enhance the performance. Being fully compatible with existing transmitter structure, the proposed algorithm does not introduce addi- tional bandwidth expansion and transmission delay. Simulations show substantial error correcting perfor- mance and synthesized speech quality improvement over conventional separate designed systems in delay and bandwidth constraint channels by using the joint source-channel decoding and demodulation （JSCCM） algorithm.

关键词： speech coding joint souree-channel coding and modulation (JSCCM) iterative decoding

FRACTAL GEOMETRY STUDY OF CORRELATION BETWEEN IMPACT TOUGHNESS OF STEEL AND PARAMETERS OF FREE-CUTTING PHASE

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Acta Metallurgica Sinica(English Letters) 1992年第4期5卷 250-255页

作者： JIANG Laizhu cui kun Huazhong University of Science and Technology,Wuhan,China Huazhong Univ of Science and Technology Wuhan China

Studies were made of the calculation of fractal dimension of transverse impact fracture sur- face,and of the correlation between impact toughness of steel and parameters of free-cutting phase by means of the developed fractal geometry model of crack *** is believed that the area fraction,f,of free-cutting phase is negligibly influential to the longitudinal im- pact toughness,as f1 .While the aspect ratio,saying ratio of length to width,of free-cut. ting phase is inversely influential to the transverse impact *** may .be the reason why the transverse impact toughness of free-cutting steel containing more rare earth contrast to sulphur is even higher than the low sulphur containing steel.

关键词： fractal geometry impact toughness free-cutting phase

Effect of edge transport barrier on required toroidal field for ignition of elongated tokamak

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Chinese Physics B 2019年第4期28卷 261-268页

作者： cui-kun Yang Ming-Sheng Chu Wen-Feng Guo Institute of Plasma Physics Chinese Academy of Sciences University of Science and Technology of China

The effect of an edge transport barrier on the toroidal field required for the ignition of an elongated tokamak is studied by modifying an analytic model which was calibrated against a transport code. It is found that the presence of the edge transport barrier will lead to a higher marginal toroidal field needed for ignition. This seemingly counter intuitive result is explained as being due to the equivalent effect of profile broadening by the edge transport barrier. This effect is further traced to its physical origin: in the case close to ignition, the fusion power input is predominantly concentrated in the center of plasma. It is demonstrated that if the fusion power input could be shifted from the center to the edge by a sufficient amount, then the presence of an edge transport barrier would lead to a reduction of the required toroidal field for ignition.

关键词： edge transport barrier toroidal field ignition tokamak

Synthesis, Characterization and Electrochemical Behavior of p-NiO/n-TiO_2/Polyaniline Composites

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Chemical Research in Chinese Universities 2011年第5期27卷 870-874页

作者： cui kun DING Guang-zhu CHEN Shi-fu LIU Jie-ping College of Chemistry and Materials Science Huaibei Normal University Huaibei 235000 t~ R. China

The p-NiO/n-TiO2/polyaniline composites were synthesized via in situ polymerization of aniline. The structure and morphology of the composites were characterized by means of X-ray diffraction（XRD）, scanning electron microscopy（SEM）, Fourier transform infrared spectroscopy（FTIR） and UV-Vis absorption spectroscopy. It was found that the p-n junction p-NiO/n-TiO2 particles were trapped in the polyaniline molecular matrix and the polyaniline was deposited on the surface of the particles to form a kind of flower cluster morphologies. The electrochemical behavior of the polyaniline composites was investigated. The electrochemical reactivity of the polyaniline was influenced by the p-NiO/n-TiO2 particles due to the effect of electron-hole pairs in these p-n junction particles. The reversibility of redox process and current intensity of the polyaniline composites with the changing of potential scan rate were also discussed.

关键词： p-NiO/n-TiO2/polyaniline composite Synthesis Characterization p-n Junction Electrochemical property

Effect of Carbon Content on Mechanoreduction of Copper Oxide

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Chinese Physics Letters 1999年第8期16卷 591-593页

作者： LIU Lin YUAN Song-liu DONG Yuan-da cui kun The State Key Laboratory of Plastic Forming Stimulation and Die&Mould Technology Huazhong University of Science&TechnologyWuhan 430074 Department of Physics Huazhong University of Science&TechnologyWuhan 430074 Institute of Materials Shanghai UniversityShanghai 200072

The reduction of CuO with different amount of carbon(CuO:C=2:1,2:1.5,and 2:2,in molar ratio)induced by ball milling is examined by x-ray diffraction and transmission electron *** is found that reduction process is closely related to the carbon *** can be completely converted into Cu if an excessive C is used(i.e.,C=1.5 or 2.0mol).However,the reduction of CuO follows a two-step process,CuO→Cu→Cu2O,if the mixture only contains a nominal C content(i.e.,C=1 mol).A tentative model in terms of solid state reaction at the interfaces is proposed to explain the effect of carbon content on the mechanoreduction of CuO.

关键词： carbon nominal content

Wave Azimuth Cutoff Compensation Method and the Multisatellite Networking Mode of SAR

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Journal of Ocean University of China 2023年第3期22卷 683-696页

作者： WAN Yong cui kun QU Ruozhao DAI Yongshou LI Ligang QU Xiaojun ZHANG Xiaoyu College of Oceanography and Space Informatics China University of PetroleumQingdao 266580China China College of Control Science and Engineering China University of PetroleumQingdao 266580China

Synthetic aperture radars(SARs)encounter the azimuth cutoff problem when observing sea ***,SARs can only capture the waves with wavelengths larger than the cutoff wavelength and lose the information of waves with smaller *** increase the accuracy of SAR wave observations,this paper investigates an azimuth cutoff compensation method based on the simulated multiview SAR wave synchronization data obtained by the collaborative observation via networked *** on the simulated data and the equivalent multiview measured data from Sentinel-1 virtual networking,the method is verified and the cutoff wavelengths decrease by 16.40%and 14.00%.The biases of the inversion significant wave height with true values decrease by 0.04 m and 0.14 m,and the biases of the mean wave period decrease by 0.17 s and 0.22 s,*** results demonstrate the effectiveness of the azimuth cutoff compensation *** on the azimuth cutoff compensation method,the multisatellite SAR networking mode for wave observations are *** highest compensation effect is obtained when the combination of azimuth angle is(95°,115°,135°),the orbital intersection angle is(50°,50°),and three or four satellites are *** study of the multisatellite networking mode in this paper can provide valuable references for the compensation of azimuth cutoff and the observation of waves by a multisatellite network.

关键词： synthetic aperture radar(SAR) compensation effect cutoff wavelength multisatellite networking mode

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Optimized strategy of rotational atherectomy of underexpanded coronary stents in patients with acute coronary syndrome

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World Journal of Emergency Medicine 2021年第3期12卷 198-201页

作者： kun cui You-quan Shi Yuan-zheng Zhang Zheng-gong Li Chang-ling Li Department of Cardiology Chongqing General HospitalChongqing 400013China Department of Cardiology the Third People’s Hospital of Xinjiang Uygur Autonomous RegionUrumqi 830000China Department of Cardiology the First People’s Hospital of TianshuiTianshui 741000China Department of Cardiology the Second Affi liated Hospital of Zhejiang University School of MedicineHangzhou 310009China

BACKGROUND:Stent under-expansion is a main cause of acute coronary syndrome(ACS),which can lead to serious clinical *** rotational atherectomy of underexpanded coronary stents(academically called stent ablation,SA)by intravascular ultrasound(IVUS)may provide more visual reference in the *** aim to analyze the procedural and long-term outcomes of the optimized strategy of SA in patients with ACS and to provide real-world data on this ***:A total of 11 patients with ACS who underwent SA between April 2017 and January 2019 were *** follow-ups were obtained either by telephone call or by scheduled *** end-points included periprocedural and postprocedural myocardial infarction,stent thrombosis,target lesion revascularization,and major adverse cardiac ***:The mean age of patients was 69.6±6.5 years,and five(45.5%)patients were *** cases presented with unstable angina and were admitted with *** patients required at least two burrs during the intervention and the size of the burr was selected based on the data of minimum lumen diameter(MLD),and the fi rst and the second burr/stent MLD ratios were 0.93(0.88-0.99)and 1.09(1.02-1.14),*** patients were treated with drug-eluting stents and two were treated with drug-coated *** were no complications including no fl ow,perforation,or burr entrapment during the *** in-hospital deaths or major adverse cardiac events were documented during the follow-up *** our study,less contrast agent and a lower dose of radiation were used during the ***:SA guided by IVUS can reduce the risk of complications,assess the results of surgery,inform the selection of stent size,and decrease the required dose of radiation and contrast.

关键词： Acute coronary syndrome Intravascular ultrasound Rotational atherectomy Underexpanded stent

Enantioselective direct aldol-type reaction of 4-hydroxycoumarin with ethyl trifluoropyruvate catalyzed by modified cinchona alkaloids

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Chinese Science Bulletin 2010年第17期55卷 1732-1734页

作者： cui HaiLei JIANG kun LIU YanKai Du Wei CHEN YingChun Key Laboratory of Drug-Targeting and Drug Deliver System of Ministrv of Education Department of Medicinal Chemistry West China School of Pharmacy Siehuan University Chengdu 610041 China

A new enantioselective aldol-type reaction of 4-hydroxycoumarins and ethyl trifluoropyruvate has been developed. In the presence of (DHQD)2PHAL (5 mol%), ethyl trifluoropyruvate could react with various 4-hydroxycoumarins to afford novel 4-hydroxycoumarin derivatives containing a tertiary trifluoromethyl alcohol center in good yields with moderate enantioselectivities.

关键词：对映选择性三氟甲基金鸡纳生物碱反应羟基改性催化乙基

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国内外模具用钢发展概况

金属热处理 2007年第1期32卷 1-11页

作者：崔崑华中科技大学塑性成形模拟及模具技术国家重点实验室湖北武汉430074

我国模具工业近年来以每年15%左右的速度快速发展,2005年模具销售额610亿元,模具净进口总量为13.3亿美元。目前,我国的模具技术及模具寿命与一些工业发达国家相比,仍存在较大差距。正确的模具用材及其热处理在提高模具寿命中有重要作用... 详细信息

我国模具工业近年来以每年15%左右的速度快速发展,2005年模具销售额610亿元,模具净进口总量为13.3亿美元。目前,我国的模具技术及模具寿命与一些工业发达国家相比,仍存在较大差距。正确的模具用材及其热处理在提高模具寿命中有重要作用。本文介绍了国内外冷作模具钢、热作模具钢和塑料模具钢的发展概况、最新进展及我国模具钢发展中存在的问题和对策。

关键词：模具用钢发展冷作模具钢热作模具钢塑料模具钢