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Transportation Safety and Environment 2020年第3期2卷 161-182页

作者： Chunyang Chen Wei Li Youmei Liu Xiang Wei Central South University School of Traffic&Transportation EngineeringChangsha410075China CRRC Zhuzhou Locomotive co. Ltd.Zhuzhou412001China Daqin Railway co. Ltd.Institute of Science and TechnologyTaiyuan030013China

In recent years,heavy-haul train technology has seen a number of innovations worldwide,and train traction-running technology has also made great progress,resulting in a rich pool of experience and a range of promising *** paper summarizes the key technologies of traction running in heavy-haul combined trains,especially locomotive and rolling-stock technology,traction technology,braking technology,control technology,communication technology and safety *** the same time,based on an analysis of practical applications,this paper further explores the main problems and urgent needs of traction equipment on heavy-haul *** an eye to the future,the heavy-haul railway system will develop in the direction of informatization,automation and intelligence,in order to build a greener,more energy-saving,safer and more efficient *** paper therefore looks forward to the technical developments of heavy-haul combined trains,and provides a reference for the development of heavy-haul railways.

关键词： heavy-haul combined train locomotive remote multi-traction traction-running safety train equipment train dynamic performance

Energy-band alignment of atomic layer deposited(HfO_2)_x(Al_2O_3)_(1-x) gate dielectrics on 4H-SiC

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Chinese Physics B 2015年第3期24卷 408-411页

作者：贾仁需董林鹏钮应喜李诚瞻宋庆文汤晓燕杨霏张玉明 School of Microelectronics Xidian University State Grid Smart Grid Research Institute Zhuzhou CSR Times Electric co. Ltd.

We study a series of（HfO2）x（Al2O3）1-x /4H-SiC MOS capacitors. It is shown that the conduction band offset of HfO2 is 0.5 e V and the conduction band offset of Hf AlO is 1.11–1.72 e V. The conduction band offsets of（Hf O2）x（Al2O3）1-x are increased with the increase of the Al composition, and the（HfO2）x（Al2O3）1-x offer acceptable barrier heights（〉 1 e V）for both electrons and holes. With a higher conduction band offset,（Hf O2）x（Al2O3）1-x/4H-SiC MOS capacitors result in a ～ 3 orders of magnitude lower gate leakage current at an effective electric field of 15 MV/cm and roughly the same effective breakdown field of ～ 25 MV/cm compared to HfO2. considering the tradeoff among the band gap, the band offset, and the dielectric constant, we conclude that the optimum Al2O3 concentration is about 30% for an alternative gate dielectric in 4H-Si C power MOS-based transistors.

关键词： energy-band alignment high k gate dielectrics 4H-SiC MOS capacitor

JNeRF:An efficient heterogeneous NeRF model zoo based on Jittor

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computational Visual Media 2023年第2期9卷 401-404页

作者： Guo-Wei Yang Zheng-Ning Liu Dong-Yang Li Hao-Yang Peng Department of computer Science and Technology Tsinghua UniversityBeijing 100084China Fitten Tech co. Ltd.Beijing 100084China

Neural radiance fields(NeRFs)for novel-view synthesis have attracted the attention of researchers in computer vision and *** traditional methods using explicit expressions,NeRFs represent a scene as an implicit neural radiance *** rendering,NeRF queries the color density at every position in the scene through a neural *** brings a wide range of possibilities for real-world 3D reconstruction and rendering,but problems remain to be *** works have improved NeRF’s sampling technique,position encoding method,network structure,etc.,but these improvements are difficult to be combined as the different modules are not well *** works have significantly sped up the core GPU computation of NeRF,leaving the deep learning framework as a major computational ***,it has been suggested to replace the frameworks by pure CUDA programs,but this limits maintainability and ***,we propose JNeRF,a unified,efficient,framework-friendly NeRF model zoo based on Jittor.

关键词： neural graphics rendering

Study on the failure mechanism of Ag-Ce contacts in DC level

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 449-452页

作者： MENG Fan-bin LU Jian-guo LU Ning-yi CHEN Zhi-chao CHEN Qi School of Materials Science and Engineering Hebei Univertity of Technology Tianjin 300130 China Hongfa Electroacoustic co. Ltd Xiamen 361021 China

Nominal contact resistance, minimum erosion and material transfer are required with low cost materials working in a wide currents range for DC relays. Ag-Ni contact materials have low contact resistance, but the erosion and material transfer are large at high current level. Ag-SnO2 contact materials have good anti-welding properties and resistance to arc erosion, but they have large contact resistance during working and are easily block SnO2 from flocking together on the surface at low current level. In this paper, the failure mechanisms of Ag-Ce contact material were studied. The surface morphologies of the contacts after electrical endurance test for Ag-Ce contact material were compared with that of Ag-Ni and Ag-SnO2 contact materials. The effect of Ce on the surface morphologies of the contacts after electrical endurance test was analyzed.

关键词： Relays Electric contact Failure analysis

Application of Rare Earth Phosphate Fertilizer in Western Area of China

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Journal of Rare Earths 2006年第z2期24卷 423-426页

作者：刘向生王甲辰杨军樊玉斌伍艳平张赫 General Research Institutes for Nonferrous Metals Grirem Advanced Materials Co.Ltd.National Rare Earth Center for Agriculture of China

Rare earth phosphate fertilizer (REPF) as base fertilizer (750 kg per hm2) was applied in the western area of China during the 'Tenth Five-Year Plan' , and the results show as follows: compared with calcium superphosphate (CK), REPF increases crops yields for maize by 17.0% , for rice by 10.5% , for wheat by 24.2% , for potato by 18.5% , for cabbage by 16.3%, for Chinese cabbage by 16.4%, for beet by 6.5%; decreases the diseased plant rate for common smut of maize by 1.0%, for maize stalk rot by 1.2%, for wheat take-all disease by 7.8%, for wheat root rot by 3.2%, for potato blackleg disease by 1.4%, for potato late blight by 6.6%; increases the sugar content of beet by 0.9°S.

关键词： REPF yield diseased plant rate agricultural products rare earths

Sex differences in cognition and their relationship to male mate choice

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Current Zoology 2019年第3期65卷 285-293页

作者： Jason KEAGY Ross MINTER Robin M.TINGHITEELLA Department of Animal Biology School of Integrative Biology University of Illinois at Urbana-Champaign Urbana IL USA Linda Crnic Institute for Down Syndrome University of Colorado School of Medicine Aurora CO USA Department of Biological Sciences University of DenverDenverCOUSA

Male cognition has gained recognition as an important potential player in sexual selection. A number of studies have found positive correlations between male sexual signals and cognitive performance an d/or female pref ere nces for males with better cog nitive performance, although other studies have not fou nd these relati on ships. Sex roles can differ dramatically, and sex differen ces in selection on cog nition likely follow from the different tasks associated with these sex roles. Here, using threespine stickleback Gasterosteus aculeatus, a species with clearly diverge nt sex roles and mutual mate choice, we focus on the cognitive trait inhibitory control because males must differentially respond to reproductive females versus other sticklebacks while defending territories and refrain from eating eggs and fry while performing paternal care. We presented fish with a detour task four times over a period of 7 days, allowing us to assess initial inhibitory control and improvement over time. We ask 1) whether there are sex differences in inhibitory control and 2) whether male mate choice is associated with female inhibitory control. Although males outperformed females on three different measures of detour task performance across four trials, these differences were largely explained by males being less neophobic than females. Females took more trials to successfully solve the detour task, even after accounting for sex differences in neophobia. Female cognitive abilities, however, were unrelated to the vigor with which males courted them. The equivocal results regarding sex differences in cognitive ability suggest further study given the very different selection pressures each sex experiences.

关键词： cognition detour task mutual mate choice sexual selection threespine stickleback

Preparation of ceria with large particle size and high appearance density

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Journal of Rare Earths 2008年第1期26卷 127-130页

作者：王嵩龄刘钧云贾江涛廖春生严纯华 State Key Laboratory of Rare Earth Materials Chemistry and Applications Peking University Jiangxi Mingda Functional Materials co. Ltd.

Cerium is one of the most abundant rare earth elements in both bastnasite and monazite. Ceria has been widely used in optical, catalytic, electrolyte, and sensor materials, with unique performances. With the development of functional materials, great interest has been focused on the synthesis and characterization of specific fine/mesoporous ceria powder. In this study, the modified precipitation and recrystallization processes combined with a controlled calcination process for fabricating the ceria with large particle size and high appearance density was reported. During precipitation, a certain amount of mineral acid such as nitric acid served as an additive, to adjust the precipitation and crystallization processes of cerium oxalates. An appropriate acidic condition could lead the process into the Oswald ripening stage and made the particles become bigger. Thus, the appearance density of powder was increased. The optimized conditions, such as the temperature, feeding speed, type and concentration of mineral acids, and the concentration of cerium-contained stock solution, were investigated and evaluated.

关键词： particle size appearance density cerium oxide preparation rare earths

Accurate Registration of Remote Sensing Images Based on Local Optimal Transformation

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Journal of Beijing Institute of Technology 2019年第2期28卷 371-382页

作者： Bo Wang Changqing Li Shi Tang Zhiqiang Zhou Hong Zhao School of Automation Beijing Institute of TechnologyBeijing 100081China Beijing Urban construction Design&Development Group co. Ltd.Beijing 100071China Beijing Navigation control Technology co. Ltd.Beijing 102200China

As the basic work of image stitching and object recognition,image registration played an important part in the image processing *** previous work in registration accuracy and realtime performance progressed very slowly,especially in registrating images with line *** innovative method for image registration based on lines is proposed,it can effectively improve the accuracy and real-time performance of image *** line feature can deal with some registration problems where point feature does not *** registration process is divided into two *** first part determines the rough registration transformation relation between reference image and test *** the similarity degree among different transformation and modified nonmaximum suppression(MNMS)algorithms are obtained,which produce local optimal solution to optimize the rough registration *** final optimal registration relation can be obtained from two registration parts according to the match *** experimental results show that the proposed method makes a more accurate registration relation and performs better in real-time situation.

关键词： initial registration relationship accurate registration relationship similarity degree local optimal transformation modified non-maximum suppression(MNMS)algorithm

Study on detinning process of a reflow conductor roll

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Rare Metals 2005年第4期24卷 325-329页

作者： FU Hanguang DAI Mingshan FU Hanfeng Department of Mechanical Engineering Tsinghua University Beijing 100084 China Baoshan Iron ＆ Steel co. Ltd. Shanghai 201900 China

Adhering tin is the main reason of a reflow conductor roll which works in an electroplating tin line （ETL）. A det- inning agent whose main composition is NaOH and KOH and assistant composition is Na2PbO2 or K2PbO2 and NaNO3 or NaNO2 has excellent detinning effects when the temperature of detinning solution is 40-80℃ and the temperature of the reflow conductor roll reaches 40-70℃. After the adhering tin layer of the reflow conductor roll is removed, the roughness of the reflow conductor roll can resume to 4.0 μm, its service life increases by 80%, and the repairing cost decreases by 90%.

关键词： electroplating tin reflow conductor roll detinning agent roughness

Efficacy and Safety of Chinese Herbal Medicines combined with Chemical Drugs for Alzheimer's Disease:A Systematic Review and Meta-Analysis

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 1-13页

作者： Li Xu Wen-Jun Chen Cai-Jun Tian Yan Zhang Yan Ma Tian-Hao Li Hong-Jie Liu Zhe Zhang Department of the First college English College of Foreign LanguageShandong University of Traditional Chinese MedicineJinanChina Department of Oncology Linyi People's HospitalLinyiChina Department of Internal Medicine of Traditional Chinese Medicine The First Clinical CollegeShandong University of Traditional Chinese MedicineJinanChina Department of Chinese Materia Medica College of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJinanChina Department of Medicinal Chemistry College of PharmacyShandong University of Traditional Chinese MedicineJinanChina community Healthcare Center Shenzhen Traditional Chinese Medicine HospitalShenzhenChina Department of Fundamentals of Traditional Chinese Medicine School of Traditional Chinese MedicineJinan UniversityGuangzhouChina Shandong co-Innovation Center of Classic TCM Formula College of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJinanChina

Objective:To evaluate the efficacy and safety of Chinese herbal medicines(CHMs)combined with chemical drugs for the treatment of Alzheimer's disease(AD).Materials and Methods:Databases were searched to retrieve randomized controlled trials(RCTs)of CHMs combined with tacrine,galantamine,rivastigmine,donepezil,or memantine,following strict inclusion and exclusion *** research papers published in English,Chinese,and Japanese were *** primary outcome was the mini-mental state examination(MMSE)score and the secondary outcomes were AD assessment scale cognitive subscale(ADAS-cog)score and safety ***-analysis was carried out using Rev Man 5.3 and subgroup analysis was conducted to identify the sources of ***:A total of 15 RCTs with 1386 participants were included in this *** donepezil was used in the retrieved ***-analyses showed that the combination of CHMs with donepezil led to significant improvement in the MMSE score(Z=9.45;P8,95%confidence interval[CI]:2.12-3.24)and a significant decrease in the ADAS-cog score(Z=5.53;Pcombination treatments relieved adverse events such as insomnia(risk ratio[RR]=0.20,95%CI:0.06-0.68;P=0.01)and hive(RR=0.10;95%CI:0.01-0.73;P=0.02).conclusions:The combination of CHMs with a chemical drug like donepezil led to significant improvements in patient cognition as well as a better safety profile when compared to the application of a chemical drug alone.

关键词： Alzheimer's disease Chinese herbal medicine donepezil memantine meta-analysis randomized controlled trials rivastigmine