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Journal of Materials Science & Technology 2016年第10期32卷 1071-1076页

作者： ni ao Daoxin Liu Shuaixing Wang Qing Zhao Xiaohua Zhang Mengmeng Zhang College of Aeronautics Institute of Corrosion and Protection Northwestern Polytechnical University National Defense Key Discipline Laboratory of Light Alloy Processing Science and Technology Nanchang Hangkong University

A composite coating containing hexagonal boron nitride（hBN） particles and titanium oxide（TiO_2） was formed on the surface of Ti-6Al-4V alloy via micro-arc oxidation（Mao）. The effect of quantity of the hBN-particles added into electrolyte on microstructure, composition, and wear behavior of the resulting composite coatings was investigated. Microstructure, phase composition, and tribological behavior of the resulting Mao coatings were evaluated via scanning electron microscopy, X-ray diffraction, and ball-on-disc abrasive tests. The results reveal that the TiO_2/hBN composite coating consisting of rutile TiO_2, anatase TiO_2, and an hBN phase was less porous than particle-free coating. Furthermore, the presence of hBN particles in the Mao coating produced an improved anti-friction property. The composite coating produced in the electrolyte containing 2 g/L of hBN particles exhibited the best wear *** outer loose layer of the Mao coatings was removed by a mechanical polishing process, which led to a significant improvement in the wear resistance and anti-friction properties of the Mao coatings and highlighted an essential lubricating role of hBN particles in the composite coatings. However, wear mechanism of the Mao coatings was not relevant to the presence of hBN particles, where fatigue wear dominated the anti-fraction properties of the Mao coatings with and without hBN particles.

关键词： Ti-6Al-4V alloy Micro arc oxidation hBN particle Wear

Improving fatigue performance of Ti-6Al-4V alloy via ultrasonic surface rolling process

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Journal of Materials Science & Technology 2019年第8期35卷 1555-1562页

作者： Chengsong Liu Daoxin Liu Xiaohua Zhang Dan Liu Amin Ma ni ao Xingchen Xu Corrosion and Protection Research Laboratory Northwestern Polytechnical University

The effect of a gradient nanostructured(GNS) surface layer obtained by ultrasonic surface rolling process(USRP) on the fatigue behavior of Ti-6Al-4V alloy has been studied in this paper. Microstructure, surface topography, surface roughness and residual stress measurements were performed to characterize the surface under different conditions. Rotating bending fatigue tests were carried out to evaluate the fatigue behavior of different treatments. The results present a remarkable fatigue performance enhancement for the Ti-6Al-4V alloy with a GNS surface layer obtained by application of USRP with respect to the untreated condition, notwithstanding its considerable surface roughness due to severe ultrasonic impacts and extrusions. Mechanical surface polishing treatment further enhances the beneficial effects of USRP on the fatigue performance. The significantly improved fatigue performance can mainly be ascribed to the compressive residual stress. Simultaneously, the GNS surface layer and surface work hardening have a synergistic effect that accompanies the effect of compressive residual stress.

关键词： Ultrasonic surface rolling process Fatigue Compressive residual stress Gradient nanostructured surface layer Ti-6Al-4V alloy

RETF: a TCP-Friendly Control Scheme Based on Rate Estimation for Stored Video

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The Journal of China Universities of Posts and Telecommunications 2003年第4期10卷 5-10页

作者： ZHANG Yu-qing,CAI An-ni,SUN Jing-ao(School of Telecommunication Engineering,Beijing University of Posts and Telecommunications, Beijing 100876, P.R. China) School of Telecommunication Engineering Beijing University of Posts and Telecommunications 北京 100876

In this paper, a TCP-friendly rate control algorithm is proposed for storedMPEG2 layered video. In this algorithm, RTT is observed at the receiver through the use of probe APPpackets, and the control interval is chosen based on the self-similar nature of MPEG2 traffic . Inaddition, the estimated receiving rate is used as an indication to the network status when nopacket loss is detected . In our simulations, a friendliness of 0.94 is obtained, and the videoquality fluctuations are acceptable with this control algorithm.

关键词： TCP-friendly rate estimation congestion control

BaMAP: A Broadband Multimedia Application Platform

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The Journal of China Universities of Posts and Telecommunications 2003年第1期10卷 60-65页

作者： SUN Song-lin, LI Qing-guo, CAI An-ni, SUN Jing-ao (Beijing University of Posts and Telecommunications, Beijing 100876, P.R. China) Beijing University of Posts and Telecommunications 北京 100876

In this paper, a broadband multimedia application platform, BaMAP, isintroduced. The BaMAP aims to offer content and service providers a good integrated environment forefficient content production, management, delivery and sharing. It supports large-scale hierarchicalstorage, as well as mechanisms for content distribution and queries from remote nodes. Theon-demand service, part of the BaMAP, offers two access interfaces, DVB-C and IP, which allow theplatform to run on most of the existing access networks.

关键词： VoD broadband multimedia

A Novel Rate Control Method for Low Delay Applications

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The Journal of China Universities of Posts and Telecommunications 2000年第4期7卷 31-34页

作者： SHI Ke wei, CAI An ni, SUN Jing ao (School of Telecommunication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, P.R. China) School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

In real time applications, the low delay rate is an important requirement of video coding. We propose a simple low delay rate control method in this paper for such applications. In this method, target bits are divided into two parts: uncontrolled and controlled bits in the frame layer. The first part is assigned to the header, syntax and motion vectors according to that spent in the previous encoded frame. The second part is assigned to DCT coeffcients by employing a rate model for mactorblock Q P determination. Experiments show that the proposed method can achieve better performance compared with that of the test model TMN5 of H .263, and slightly worse performance, but with lower computation complexity, compared with that of the TMN8 of H.263+ .

关键词： rate cotnrol low delay H .263+ low bit rate video cod|

Blocking Probability Based Hierarchical Storage Design in VoD Systems

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The Journal of China Universities of Posts and Telecommunications 2003年第1期10卷 44-48页

作者： LI Qing-guo, SUN Song-lin, CAI An-ni, SUN Jing-ao (Beijing University of Posts and Telecommunications, Beijing 100876, P.R. China) Beijing University of Posts and Telecommunications 北京 100876

In this paper, we discuss the relationship between the blocking probabilityand the configuration of storage hierarchy in a Video on Demand ( VoD) server using the queueingmodel we propose. With this model, the optimal... 详细信息

关键词： VoD hierarchical storage blocking probability

A Content Based Search Algorithm for Motion Estimation

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The Journal of China Universities of Posts and Telecommunications 2000年第3期7卷 25-27页

作者： SHI Ke wei, CAI An ni, SUN Jing ao (School of Telecommunication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, P.R.China) School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

The basic search algorithm to implement Motion Estimation ( ME ) in the H .263 encoder is a full search. It is simple but time consuming. Traditional search algorithms are fast, but may cause a fall in image quality or an increase in bit rate in low bit rate applications. A fast search algorithm for ME with consideration on image content is proposed in this paper. Experiments show that the proposed algorithm can offer up to 70 percent savings in execution time with almost no sacrifice in PSNR and bit rate, compared with the full search.

关键词： motion estimation video coding H .263 content based

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美国“安全和成功学校框架”探析及启示

教学与管理 2024年第34期 71-76页

作者：李汉学倪奥华湖南第一师范学院初等教育学院长沙410205 北京大学教育学院北京100871

美国通过对校园暴力成因的深入分析制定了“安全和成功学校框架”,认为学校安全和积极的学校氛围要通过有效资源整合和多方协作来实现。全面资源整合、全方位协同、全程心理干预和全链条衔接是美国“安全和成功学校框架”的核心内容。... 详细信息

美国通过对校园暴力成因的深入分析制定了“安全和成功学校框架”,认为学校安全和积极的学校氛围要通过有效资源整合和多方协作来实现。全面资源整合、全方位协同、全程心理干预和全链条衔接是美国“安全和成功学校框架”的核心内容。美国“安全和成功学校框架”体系下,学校校长是“安全和成功学校框架”的领导者、学校行政人员是“安全和成功学校框架”的日常维护者、学校心理健康专业人员是学校安全氛围和心理健康服务的保障与供给者、媒体是校园安全的舆论创设者。“安全和成功学校框架”提出后,美国国家层面和地方层面的相关机构和行业协会积极参与,取得了一定成效。美国“安全和成功学校框架”的经验启示我国:在防治校园暴力过程中,应以学生为本,准确把握防治校园暴力的本质目标;通过权责明确下的全员参与,构建防治校园暴力的资源库;充分发挥媒体正向功能,营造防治校园暴力的舆论场。

关键词：美国校园暴力 “安全和成功学校框架”

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科举制度对女性生存状态影响考述

渭南师范学院学报 2017年第11期32卷 34-38页

作者：林奥妮辽宁师范大学文学院辽宁大连116081

女性作为被科举制度排斥在外的一个社会群体,却与科举有着千丝万缕的关联。明清小说中饱读诗书满腹才学的女性形象、近代戏曲作品中光辉鲜亮的女状元形象、服务于士子科考的妻子母亲妓女等女性形象,这形形色色的女性角色共同展现了科举... 详细信息

女性作为被科举制度排斥在外的一个社会群体,却与科举有着千丝万缕的关联。明清小说中饱读诗书满腹才学的女性形象、近代戏曲作品中光辉鲜亮的女状元形象、服务于士子科考的妻子母亲妓女等女性形象,这形形色色的女性角色共同展现了科举制度影响下,处于封建社会的女性最真实的生存状态。她们的悲欢离合、嬉笑怒骂与士子的科举结果密不可分,归根结底,她们的人生命运全都悬系于科举制度。

关键词：文学才女女状元士子周遭女性

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唐传奇的叙事艺术

哈尔滨学院学报 2017年第8期38卷 83-86页

作者：林奥妮辽宁师范大学文学院辽宁大连116081

唐传奇是我国文言小说发展到成熟阶段的标志,其叙事艺术成就斐然可观,主要表现在以全知全能视角、第三人称限知视角和多种视角相互交换为代表的叙事视角;情节在叙事结构中起到链接作用;感恩式、报仇式、醒悟式等丰富多样的叙事逻辑。这... 详细信息

唐传奇是我国文言小说发展到成熟阶段的标志,其叙事艺术成就斐然可观,主要表现在以全知全能视角、第三人称限知视角和多种视角相互交换为代表的叙事视角;情节在叙事结构中起到链接作用;感恩式、报仇式、醒悟式等丰富多样的叙事逻辑。这些叙事艺术奠定了唐传奇在文学史上的独特地位,推动了后世小说的成熟发展。

关键词：唐传奇叙事视角叙事结构叙事逻辑