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New Blocking Artifacts Reduction Method Based on Wavelet Transform

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Semiconductor Photonics and Technology 2007年第1期13卷 43-47页

作者： SHI Min yi qing-ming Department of Electronic Engineering Jinan University Guangzhou 510632 CHN

It is well known that a block discrete cosine transform compressed image exhibits visually annoying blocking artifacts at low-bit-rate. A new post-processing deblocking algorithm in wavelet domain is proposed. The algorithm exploits blocking-artifact features shown in wavelet domain. The energy of blocking artifacts is concentrated into some lines to form annoying visual effects after wavelet transform. The aim of reducing blocking artifacts is to capture excessive energy on the block boundary effectively and reduce it below the visual scope. Adaptive operators for different subbands are computed based on the wavelet coefficients. The operators are made adaptive to different images and characteristics of blocking artifacts. Experimental results show that the proposed method can significantly improve the visual quality and also increase the peak signal-noise-ratio(PSNR) in the output image.

关键词： block discrete cosine transform(BDCT) blocking artifacts wavelet transform

New Soft Output Viterbi Algorithm for Mobile Communication System

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Semiconductor Photonics and Technology 2006年第4期12卷 228-232页

作者： yi qing-ming SHI Min Department of Electronic and Engineering Jinan University Guangzhou 510632 CHN

Soft output Viterbi algorithm （SOVA） is a turbo decoding algorithm that is suitable for hardware implementation. But its performance is not so good as maximum a posterior probability（MAP） algorithm. So it is very important to improve its performance. The non-correlation between minimum and maximum likelihood paths in SOVA is analyzed. The metric difference of both likelihood paths is used as iterative soft information, which is not the same as the traditional SOVA. The performance of the proposed SOVA is demonstrated by the simulations. For 1 024-bit frame size and 9 iterations with signal to noise ratio from 1 dB to 4 dB, the experimental results show that the new SOVA algorithm obtains about more 0. 4 dB and 0. 2 dB coding gains more than the traditional SOVA and Bi-SOVA algorithms at bit error rate（BER） of 1 × 10^-4 , while the latency is only half of the Bi-direction SOVA decoding.

关键词： SOVA algorithm Maximum likelihood path Minimum likelihood path Coding gain

Warming intensified the effects of nitrogen addition on N_(2)O emissions from alpine meadow in the northern qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第1期15卷 101-112页

作者： ming-Jie LI yi-qing GE Hasbagan GANJURJAV Guo-Zheng HU Hong-Bao WU Jun YAN Shi-Cheng HE qing-Zhu GAO Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China National Agricultural Experimental Station for Agricultural Environment Nagqu 852100China Ecology and Nature Conservation Institute Chinese Academy of ForestryBeijing 100091China College of Resource and Environment Anhui Science and Technology UniversityFengyang 233100China Nagqu Agriculture Animal Husbandryand Prataculture Science and Technology Research and Extension CenterNagqu 852100China Tongliao Experimental Middle School Tongliao 028000China

Warming and nitrogen(N)addition may impact soil nitrous oxide(N_(2)O)emissions,but the relationship between plant community composition and soil microbial activities remains *** a two-year field study in the qinghai-Tibet Plateau,open-top chambers were used to quantify the effects of warming,N-addition,and their interactions on N_(2)O *** found that the N-addition greatly increased N_(2)O emissions by 77.4%in 2018 when compared to the control *** contrast,warming showed little effect on N_(2)0 emissions but did increase the activity of enzymes associated with soil nitrification and denitrification.A combined effect of warming and N-addition of resulted in 208.6%(2018)and 90.8%(2019)increase in N_(2)0 emissions,respectively,compared to the individual treatments of warming or *** warming in alpine meadows is causally linked to increased legume biomass which is further intensified with the *** legume biomass(pming further intensifies this *** increased dominance of legumes and microbial N content contributes to this *** outcomes suggest that warming and atmospheric N deposition can stimulate N_(2)O emissions of alpine meadows inthefuture.

关键词： Alpine meadow Community composition Nitrogen addition Nitrous oxide flux qinghai-Tibet Plateau Warming

Implementation of Synchronization Technology in Orthogonal Frequency Division Multiplex System Based on Field Programming Gate Array

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Semiconductor Photonics and Technology 2008年第1期14卷 32-36页

作者： yi qing-ming XIE Sheng-li College of Electronics ＆ Information South China University of Technology Guangzhou 510641 CHN Department of Electronics Engineering Jinan University Guangzhou 510632 CHN

In this paper,analyzed is the symbol synchronization algorithm in orthogonal frequency division multiplex(OFDM)system,and accomplished are the hardware circuit design of coarse and elaborate synchronization *** on the analysis of coarse and elaborate synchronization algorithms,multiplexed are,the module accumulator,division and output judgement,which can evidently save the hardware resource *** analysis of circuit sequence and wave form simulation of the design scheme shows that the proposed method efficiently reduce system resources and power consumption.

关键词： orthogonal frequency division multiplex timing synchronization field programmable gate array

Novel Efficient De-blocking Method for Highly Compressed Images

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Semiconductor Photonics and Technology 2007年第2期13卷 122-125,145页

作者： SHI Min yi qing-ming YANG Liang Department of Electronic Engineering Jinan University Guangzhou 510632 CHN

Due to coarse quantization, block-based discrete cosine transform(BDCT) compression methods usually suffer from visible blocking artifacts at the block boundaries. A novel efficient de-blocking method in DCT domain is proposed. A specific criterion for edge detection is given, one-dimensional DCT is applied on each row of the adjacent blocks and the shifted block in smooth region, and the transform coefficients of the shifted block are modified by weighting the average of three coefficients of the block. Mean square difference of slope criterion is used to judge the efficiency of the proposed algorithm. Simulation results show that the new method not only obtains satisfactory image quality, but also maintains high frequency information.

关键词： block-based discrete cosine transform(BDCT) blocking artifacts image compression

Astrometric Observations of NEA 1998 HH49 Using the Daocheng 50 cm Telescope

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Research in Astronomy and Astrophysics 2024年第7期24卷 71-78页

作者： Huan Xu Xiang-ming Cheng yi-Gong Zhang Teng-Fei Song Zhen-Jun Zhang qing-Yu Peng Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Engineering Laboratory on Applied Astronomical Technology of Yunnan Kunming 650216China School of Information Engineering Kunming UniversityKunming 650214China School of Computer Science and Information Engineering Anyang Institute of TechnologyAnyang 455000China Department of Computer Science Jinan UniversityGuangzhou 510632China Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China

This study details an astrometric observation campaign of the Near-Earth Asteroid 1998 HH49,conducted with the aim of refining our understanding of its physical *** the 50 cm telescope located at the Wumingshan Mountain in Daocheng,Sichuan,images were obtained over four nights,from 2023 October 19 to October *** observations were processed using Astrometrica software,facilitating the precise determination of the asteroid's *** observational results were compared with the ephemerides from three distinct sources to verify accuracy:the Jet Propulsion Laboratory(JPL)Horizons System,the Institut de Mécanique Céleste et de Calcul deséphémérides(IMCCE)Miriade,and the Near-Earth Objects Dynamic Site(NEODyS-2).When compared with the JPL ephemeris,a mean observed-minus-calculated(O-C)result of 0.″07 in the *** and-0.″35 in the *** was ***,the comparison with the IMCCE ephemeris yielded mean O-C results of 0.″08 in the *** and-0.″06 in the *** comparison with the NEODyS-2 ephemeris yielded the mean O-C results of 0.″06 in ***-0.″49 in *** study's findings demonstrate a general consistency between the observed data and the ephemeris predictions,with minor discrepancies observed across the data ***,both the JPL and NEODyS-2 ephemerides show that the residuals in the *** exceed those in the *** disparities may result from atmospheric differential color refraction,ephemeris discrepancies,observational errors,and other ***,it is worth noting that further investigation is required due to the potential influence of additional ***,the Daocheng 50 cm Telescope exhibits the ability to conduct high-precision positional measurements.

关键词： astrometry ephemerides time

Design of weak current measurement system and research on temperature impact

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Nuclear Science and Techniques 2024年第4期35卷 46-56页

作者： Chu-Xiang Zhao San-Gang Li Rong-Rong Su Li Yang ming-Zhe Liu qing-Yue Xue Shan Liao Zhi Zhou qing-Shan Tan Xian-Guo Tuo yi Cheng College of Nuclear Technology and Automation Engineering Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China University of Science and Technology of China Hefei 230026China School of Physics and Electronic Engineering Sichuan University of Science and EngineeringZigong 643000China

A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization *** system incorporates a second-order low-pass filter circuit and the Kalman filtering algorithm to effectively filter out noise and minimize interference in the measurement *** conducted under normal temperature conditions has demonstrated the system's high precision ***,it was observed that temperature variations can affect the measurement *** were collected across temperatures ranging from -20 to 70℃,and a temperature correction model was established through linear regression fitting to address this *** feasibility of the temperature correction model was confirmed at temperatures of -5 and 40℃,where relative errors remained below 0.1% after applying the temperature *** research indicates that the designed measurement system exhibits excellent temperature adaptability and high precision,making it particularly suitable for measuring weak currents.

关键词： Weak current measurement system Neutron ionization chamber Kalman filter algorithm Temperature correction model

Milk fat globule epidermal growth factor 8 alleviates liver injury in severe acute pancreatitis by restoring autophagy flux and inhibiting ferroptosis in hepatocytes

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World Journal of Gastroenterology 2024年第7期30卷 728-741页

作者： qing Cui Hang-Cheng Liu Wu-ming Liu Feng Ma yi Lv Jian-Cang Ma Rong-Qian Wu yi-Fan Ren Department of Cardiology Xi’an Central Hospital Affiliated to Xi’an Jiaotong UniversityXi’an 710003Shaanxi ProvinceChina Department of General Surgery The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine Shaanxi Provincial Center for Regenerative Medicine and Surgical EngineeringFirst Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Vascular Surgery The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina

BACKGROUND Liver injury is common in severe acute pancreatitis(SAP).Excessive autophagy often leads to an imbalance of homeostasis in hepatocytes,which induces lipid peroxidation and mitochondrial iron deposition and ultimately leads to *** previous study found that milk fat globule epidermal growth factor 8(MFG-E8)alleviates acinar cell damage during SAP via binding toαvβ3/5 ***-E8 also seems to mitigate pancreatic fibrosis via inhibiting chaperone-mediated *** To speculate whether MFG-E8 could also alleviate SAP induced liver injury by restoring the abnormal autophagy *** SAP was induced in mice by 2 hly intraperitoneal injections of 4.0 g/kg L-arginine or 7 hly injections of 50μg/kg cerulein plus ***8-knockout mice were used to study the effect of MFG-E8 deficiency on SAPinduced liver ***,a specificαvβ3/5 integrin inhibitor,was used to investigate the possible mechanism of *** The results showed that MFG-E8 deficiency aggravated SAP-induced liver injury in mice,enhanced autophagy flux in hepatocyte,and worsened the degree of *** MFG-E8 reduced SAP-induced liver injury in a dose-dependent ***,MFG-E8 mitigated excessive autophagy and inhibited ferroptosis in liver *** abolished MFG-E8’s beneficial effects in SAP-induced liver *** MFG-E8 acts as an endogenous protective mediator in SAP-induced liver ***-E8 alleviates the excessive autophagy and inhibits ferroptosis in hepatocytes by binding to integrinαVβ3/5.

关键词： Autophagy flux Ferroptosis Liver injury Milk fat globule epidermal growth factor 8 αvβ3/5 integrins Acute pancreatitis

Detection of astrophysical gravitational wave sources by TianQin and LISA

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 123-163页

作者： Alejandro Torres-Orjuela Shun-Jia Huang Zheng-Cheng Liang Shuai Liu Hai-Tian Wang Chang-qing Ye yi-ming Hu Jianwei Mei MOE Key Laboratory of Tian Qin Mission Tian Qin Research Center for Gravitational PhysicsSchool of Physics and AstronomyFrontiers Science Center for Tian QinGravitational Wave Research Center of CNSASun Yat-Sen University(Zhuhai Campus)Zhuhai 519082China Department of Physics The University of Hong KongHong Kong 999077China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing100871China

TianQin and LISA are space-based laser interferometer gravitational wave(GW)detectors planned to be launched in the *** detectors will detect low-frequency GWs around 10^(-2)Hz;however,Tian Qin is more sensitive to frequencies above this common sweet-spot while LISA is more sensitive to frequencies below 10^(-2)***,Tian Qin and LISA will be able to detect the same sources but with different accuracy depending on the source and its *** consider some of the most important astrophysical sources—massive black hole binaries,stellar-mass black hole binaries,double white dwarfs,extreme mass ratio inspirals,light and heavy intermediate mass ratio inspirals,as well as the stochastic gravitational background of astrophysical origin—that Tian Qin and LISA will be able to *** each of these sources,we analyze how far they can be detected(detection distance)and how well their parameters can be measured(detection accuracy)using a Fisher Matrix *** compare the results obtained by the three detection scenarios(Tian Qin alone,LISA alone,and joint detection by LISA and Tian Qin)highlighting the gains from joint detection as well as the contribution of Tian Qin and LISA to a combined study of astrophysical *** particular,we consider the different orientations,lifetimes,and duty cycles of the two detectors to explore how they can give a more complete picture when working together.

关键词： wave extreme stochastic