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An Improved Rate Control Method Based on Modification at Scene Change for H.264

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Wuhan University Journal of Natural Sciences 2007年第6期12卷 1047-1050页

作者： RU Guobao gao Wenli FU jianfeng School of Electronic Information Wuhan University Wuhan430072 Hubei China

This paper presents an improved rate control method for H.264. First, the scene changes are detected by the average absolute difference of the brightness histograms between the adjacent frames. Then, the bit allocation and quantization parameters are adjusted, using a certain threshold. In addition, the calculation of the mean absolute difference （MAD） is modified in an alternative way, which makes the rate distortion optimization （RDO） more accurate. Extensive simulation results show that the proposed method, compared with G012, can improve the average peak signal-to-noise ratio （PSNR） and moderate the image quality.

关键词： brightness histogram mean absolute difference (MAD) rate distortion optimization (RDO) rate control scene change

Design memristor-based computing-in-memory for AI accelerators considering the interplay between devices, circuits, and system

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Science China(Information Sciences) 2023年第8期66卷 243-253页

作者： Junjie AN Linfang WANG Wang YE Weizeng LI Hanghang gao Zhi LI Zhidao ZHOU Jinghui TIAN jianfeng gao Chunmeng DOU Qi LIU School of Microelectronics University of Science and Technology of China State key Lab of Fabrication Technologies for Integrated Circuits Institute of MicroelectronicsChinese Academy of Sciences School of Microelectronics University of Chinese Academy of Sciences Frontier Institute of Chip and System State Key Laboratory of ASIC and System Fudan University

Recent advances in developing beyond von Neumann architectures have moved the memristive devices to the forefront as one of the key enablers to realizing memristive computing-in-memory(m CIM)structures, which shows a great promise to boost the energy-efficiency and the performance of artificial intelligence(AI) chips. In this study, by considering the interactions between devices, circuits, and systems in the m CIM design, we propose several cross-layer design techniques, including(1) the BL-SL interactive forming protection(BSIFP) circuit that can reduce the voltage drop on the selected transistor, suppress the current overshoot by 65.96%, and improve the bit-cell density by more than 10.19%,(2) the clamping transistor trimming scheme(CTTS) to prevent the multiply-and-accumulate(MAC) signal margin degradation from chip-to-chip resistance variations, and(3) dynamic input-parallelism and output-precision(DIPOP) that can reduce the energy cost by 22.92% in a typical inference task with negligible accuracy loss. The results demonstrate the significant role of the cross-layer-interactive approach and provide a preliminary guideline for highly-efficient m CIM design.

关键词： memristor resistive memory computing-in-memory artificial intelligence cross-layer co-design

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A K-Median Facility Location Agent for Low-Cost Service Selection in Digital Community Network

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China Communications 2014年第11期11卷 174-186页

作者： gao Cong MA jianfeng School of Computer Science and Technology Xidian University Xi'an 710071 Shaanxi Province P. R. China

With the increasing number of web services, it becomes a difficult task for an ordinary user to select an appropriate service. Hence, it is conventional that users in a digital community network take part in a collaborative mechanism for the purpose of service selection. The participation usually brings unnecessary burdens for users, such as giving opinions, storing service information. Extra communication overhead hinders the performance of the network. Thus, the community administrators are facing a problem of how to obtain an overall service selection result for the whole community readily and effectively. To address this problem, we present a k-median facility location agent model. The model analyzes the procedure of service selection through five entities and six types of messages. Two algorithms are elaborated in pursuit of a global optimization concerning connection costs between users and facilities where services are deployed. To evaluate our model, we conduct extensive simulations and present a detailed analysis of the simulation results.

关键词： web services service selection k-median low cost service providers

Sm-Nd dating and Nd-Sr isotopic characteristics of the Shimian ophiolite suiten,Sichuan Province

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Chinese Science Bulletin 2002年第22期47卷 1897-1901页

作者： SHEN Weizhou XU Shijin gao jianfeng YANG Zhusheng YANG Qiwen Department of Earth Sciences and State Key Laboratory of Mineral Deposit Research Nanjing UniversityNanjing 210093China Geological Survey Institute Panxi Geological TeamSichuan Bureau of Geology and Mineral Exploration and DevelopmentXichang 615000China

By mcasuring the Sm-Nd and Rb-Sr isotopiccompositions of harzburgite and gabbro from Shimianophiolite suite, we got the whole rock Sm-Nd isochron age of(938 ± 30) Ma (2σ), and the e Nd of 7.6 ± 0.8 (2σ), which showsthat the ophiolite was formed at the Early *** obvious change (0.70209-0.70708) of Isr values of theophiolite is caused by the meteoric hydrothermal *** high εNd values indicate that the primitive magma wasderived from the intense depleted mantle rescrvoir. It is sug-gested that this area was in a back-arc basin environmentduring the Early Neoproterozic.

关键词： Sm-Nd dating Nd-Sr isotopes ophiolite suite back-arc basin Shimian County Sichuan Province.

The Pengguan tectonic dome of Longmen Mountains, Sichuan Province:Mesozoic denudation of a Neoproterozoic magmatic arc-basin system

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Science China Earth Sciences 2008年第11期51卷 1545-1559页

作者： YAN DanPing ZHOU MeiFu WEI GuoQing gao jianfeng LIU ShaoFeng XU Ping SHI XiaoYing State Key Laboratory of Geological Processes and Mineral Resources Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology of Ministry of EducationChina University of GeosciencesBeijing 100083China Department of Earth Sciences The University of Hong KongHong Kong SARChina

Neoproterozoic igneous and metamorphic complexes occur as tectonic domes in the Longmen Mountains of the western margin of the Yangtze Block, and are important in reconstructing the Rodinian supercontinent and constraining the timing and mechanism of tectonic denudational processes. The Pengguan dome consists of granitic intrusions and metamorphic rocks of the Huangshuihe Group and is tectonically overlain by ductilly deformed Sinian to Paleozoic strata. The plutonic intrusions consist of granites with abundant amphibolite enclaves. New LA-ICP-MS zircon U-Pb dating yielded an emplacement age of 809±3 Ma and a protolith age of 844±6 Ma for the granite. The granitic rocks have geochemical signatures typical of A-type granites, indicating their formation under an extensional environment, by melting of newly formed tonalite-trondhjemite-granodiorite (TTG) rocks. A detachment fault, characterized by variable ductile shear deformation of S-C fabric and ESE-ward kinematics, separates the Pengguan dome from the Sinian-Paleozoic cover. 40Ar/39Ar dating of muscovite from the mylonite in the detachment fault of the dome demonstrates that ductile deformation occurred at ~160 Ma. This study indicates the existence of a Neoproterozoic magmatic arc-basin system, which was denudated by a Jurassic middle crustal ductile channel flow along the Longmenshan thrust belt.

关键词： Pengguan tectonic dome Neoproterozoic magmatic arc Mesozoic denudation

Pyrite Surface after Thiobacillus ferrooxidans Leaching at 30℃

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Acta Geologica Sinica(English Edition) 2006年第3期80卷 451-455页

作者： LU Jianjun LU Xiancai WANG Rucheng LI Juan ZHU Changjian gao jianfeng Department of Earth Sciences State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing Jiangsu 210093

In order to investigate the effect of Thiobacillusferrooxidans on the oxidation of pyrite, two parallel experiments, which employed H2SO4 solutions and acidic solutions inoculated with ThiobaciUus ferrooxidans, were designed and carried out at 30℃. The initial pH of the two solutions was adjusted to 2.5 by dropwise addition of concentrated sulphuric acid. The surfaces of pyrite before exposure to leaching solutions and after exposure to the H2SO4 solutions and acidic solutions inoculated with Thiobacillus ferrooxidans were observed by scanning electron microscopy （SEM）. There were a variety of erosion patterns by Thiobacillusferrooxidans on the bio-leached pyrite surfaces. A conclusion can be drawn that the oxidation of pyrite might have been caused by erosion of the surfaces. Attachment of the bacteria to pyrite surfaces resulted in erosion pits, leading to the oxidation of pyrite. It is possible that the direct mechanism plays the most important role in the oxidation of pyrite. The changes in iron ion concentrations of both the experimental solutions with time suggest that ThiobaciUus ferrooxidans can enhance greatly the oxidation of pyrite.

关键词： pyrite surface bio-oxidation erosion pattern Thiobacillus ferrooxidans

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Neural Regeneration Research 2010年第17期5卷 1313-1318页

作者： Jiansheng Li Ke Liu Xinke Yang jianfeng gao Youlong Zhou Yuewu Zhao Zhengguo Liu Jingxia Liu Geriatrics Department Henan College of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina Fourth In-patient Department of Encephalopathy First Affiliated HospitalHenan College of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina Department of Pathology Hunan Province People's HospitalZhengzhou 450000Henan ProvinceChina

Cerebral angiogenesis in the early stages after cerebral ischemia injury is essential for the recovery of nerve function,in which fetal liver kinase-1（Flk-1）,as a major regulator of vasculogenesis and angiogenesis,plays a very important *** density（MVD）was greater in an aged model group compared with the young sham operated group（P 〈 0.01）.MVD and the sum of the lumen area were decreased in the aged group at 1,3,6 and 12 days following ischemia/reperfusion（I/R）injury compared with the young model group（P 〈 0.05 and P 〈 0.01,respectively）.Flk-1 protein and mRNA expression was greater in the aged model group when compared with the young sham operated group（P 〈 0.01）.Flk-1 protein and mRNA expression was lower in the aged group at 1,3,6 and 12 days after I/R compared with the young model group（P 〈 0.01）.Flk-1 expression in aged rats attenuated rapidly,but was still maintained at relatively higher levels at 12 days following I/R in younger *** results suggest that angiogenesis was weakened after cerebral I/R in aged rats,and the mechanism of which might be correlated with attenuated expression of Flk-1 protein and mRNA.

关键词： cerebral ischemia/reperfusion angiogenesis fetal liver kinase-1 aged rats vascular endothelial growth factor receptor

Rare Earth Element and Trace Element Features of Gold-bearing Pyrite in the Jinshan Gold Deposit,Jiangxi Province

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Acta Geologica Sinica(English Edition) 2010年第3期84卷 614-623页

作者： MAO Guangzhou HUA Renmin gao jianfeng ZHAO Kuidong LONG Guangming LU Huijuan YAO Junming State Key Laboratory of Mineral Deposits Research School of Earth Science and Engineering Nanjing University Nanjing 210093 China College of Geological Science and Engineering Shandong University of Science and Technology Qingdao 266510 China

Jinshan gold deposit is located in northeastern Jiangxi,South China,which is related to the ductile shear *** has a gold reserve of more than 200 tons,with 80%of gold occurring in pyrite. The LREE of gold-bearing pyrite is as higher as 171.664 ppm on average,with relatively higher light rare earth elements（LREE;159.556 ppm） and lower HREE（12.108 ppm）.TheΣLREE/ΣHREE ratio is 12.612 and（La/Yb）_N is *** indicate that pyrite is rich in ***（La/Sm）_N ratio is 3.758 and that of（Gd/Yb）_N is *** are obvious LREE *** rare earth element（REE） distribution patterns show obvious Eu anomaly with averageδEu values of 0.664,andδCe anomalies of *** characteristics are similar to those of wall rocks（regional metamorphic rocks）,but different from those of the Dexing granodiorite porphyry and Damaoshan biotite *** features indicate that the ore-forming materials in the Jinshan gold deposit derived from the wall rocks, and the ore-forming fluids derived from metamorphic *** Co/Ni ratio（average value 0.38） of pyrite suggests that the Jinshan gold deposit formed under a medium-low *** is inferred from the values of high-field strength elements,LREE,Hf/Sm,Nb/La,and Th/La of the pyrite that the ore-forming fluids of the Jinshan gold deposit derived from metamorphic water with Cl〉F.

关键词： rare earth element trace element pyrite ore-forming fluid geochemistry Jinshan gold deposit

Nano-scaled transistor reliability characterization at nano-second regime

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Science China(Information Sciences) 2021年第10期64卷 272-274页

作者： Ran CHENG Ying SUN Yiming QU Wei LIU Fanyu LIU jianfeng gao Nuo XU Bing CHEN School of Micro-Nano Electronics Zhejiang University College of Electronic Engineering and Information Science Zhejiang University Institute of Microelectronics Chinese Academy of Sciences Department of Electrical Engineering and Computer Sciences University of California

Dear editor,In recent years, novel MOSFET structures such as fullydepleted silicon-on-insulator(FDSOI) MOSFET and FinFET are adopted by the industry for their excellent electrostatic behavior and higher on-state current per ***, these novel structured transistors suffer from severe self-heating effects(SHE) owing to the more heat generation but lower thermal conductivity of the ultrathin Si channel [1].

关键词： FDSOI Self-heating effect Reliability PRBS Vth shift

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