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某电机齿轮冷挤压裂纹形成机理研究

塑性工程学报 2024年第8期31卷 208-215页

作者：董文正王丹林启权刘鲜蓉许小龙湘潭大学机械工程与力学学院湖南湘潭411105 中南大学极端服役性能精准制造国家重点实验室湖南长沙410083 玉环普天单向器有限公司浙江玉环317600

针对材料为20Cr的某电机齿轮在冷挤压成形时内齿齿顶面上出现的裂纹缺陷,基于DEFORM-3D对其冷挤压过程进行了模拟,研究了其裂纹形成机理。有限元结果表明,内齿的金属流动速度小于中部及下部外齿的流动速度,内齿齿顶面上齿根处的金属流... 详细信息

针对材料为20Cr的某电机齿轮在冷挤压成形时内齿齿顶面上出现的裂纹缺陷,基于DEFORM-3D对其冷挤压过程进行了模拟,研究了其裂纹形成机理。有限元结果表明,内齿的金属流动速度小于中部及下部外齿的流动速度,内齿齿顶面上齿根处的金属流动速度最小,此处流动最不均匀,易产生应力集中;对齿面的最大主应力及损伤分布进行了分析,得出在内齿齿顶面上,中部及距离下端面1 mm左右的位置应力集中最明显,拉应力较大且大于材料抗拉强度,损伤值也较大且大于临界损伤值,会产生裂纹,与实际情况相符合。通过改变凹模入模角来控制成形缺陷情况,当凹模入模角为23°时,齿根处拉应力下降,损伤值减小,投入生产后次品率从原本的50%降为1%。

关键词：冷挤压齿轮裂纹缺陷模具优化韧性断裂损伤

Load balancing routing for single-layered satellite networks

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 92-99页

作者： RAO Yuan WANG Ru-chuan xu xiao-long College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China

The varying population density leads to imbalanced utilization rate of satellites. To ensure an intelligent engineering of traffic over satellite networks, a distributed routing scheme for single-layered satellite network, load balancing routing protocol based on mobile agent （LBRP-MA） is proposed. For LBRP-MA, mobile agents explore route by migrating autonomously. Upon arriving at destination, mobile agents migrate back. On each intermediate satellite, mobile agents evaluate path cost considering satellite geographical position as well as inter-satellite link （ISL） cost, and finally take ISL congestion index into account to update routing tables. Through simulations on the Courier-like constellation, the proposed approach is shown to achieve guaranteed end-to-end delay bound and decrease packet loss ratio with better throughput, which is especially suitable for data transferring in case of high traffic load. Moreover, results of the complexity analysis demonstrate that LBRP-MA can have low onboard signaling, storage and computation requirements. Furthermore, issues of LBRP-MA such as ISL congestion index and cost modification factor are discussed.

关键词： load balancing mobile agent satellite networks routing

NC-MACPABE: Non-centered multi-authority proxy re-encryption based on CP-ABE for cloud storage systems

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Journal of Central South University 2017年第4期24卷 807-818页

作者： xu xiao-long ZHANG Qi-tong ZHOU Jing-lan College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China State Key Laboratory for Novel Software Technology (Nanjing University) Nanjing 210046 China

The cloud storage service cannot be completely trusted because of the separation of data management and ownership, leading to the difficulty of data privacy protection. In order to protect the privacy of data on untrusted servers of cloud storage, a novel multi-authority access control scheme without a trustworthy central authority has been proposed based on CP-ABE for cloud storage systems, called non-centered multi-authority proxy re-encryption based on the cipher-text policy attribute-based encryption(NC-MACPABE). NC-MACPABE optimizes the weighted access structure(WAS) allowing different levels of operation on the same file in cloud storage system. The concept of identity dyeing is introduced to improve the users' information privacy further. The re-encryption algorithm is improved in the scheme so that the data owner can revoke user's access right in a more flexible way. The scheme is proved to be secure. And the experimental results also show that removing the central authority can resolve the existing performance bottleneck in the multi-authority architecture with a central authority, which significantly improves user experience when a large number of users apply for accesses to the cloud storage system at the same time.

关键词： cloud storage data privacy proxy re-encryption multi-authority

Credibility protection for resource sharing and collaborating in non-center network computing environments

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The Journal of China Universities of Posts and Telecommunications 2014年第3期21卷 46-55页

作者： xu xiao-long TU Qun WANG Xin-heng WANG Ru-chuan College of Computer Nanjing University of Posts and Telecommunications State Key Laboratory for Novel Software Technology Nanjing University School of Computing University of the West of Scotland Paisley PA1 2BE United Kingdom

Non-center network computing environments have some unique characteristics, such as instability, heterogeneity, autonomy, distribution and openness, which bring serious issues of security and reliability. This article proposes a brand-new credibility protection mechanism for resource sharing and collaboration in non-center network computing environments. First, the three-dimensional hierarchical classified topology （3DHCT） is proposed, which provides a basic framework for realizations of the identity credibility, the behavior credibility and the capability credibility. Next, the agent technology is utilized to construct the credibility protection model. This article also proposes a new comprehensive credibility evaluation algorithm with simple, efficient, quantitative and able to meet the requirements of evaluating behavior credibility and the capability credibility evaluation as well. The Dempster-Shafer theory of evidence and the combination rule are used to achieve the evaluation of the capability credibility. The behavior credibility is evaluated with the current and historical performance of nodes for providers and consumers to realize more accurate prediction. Based on the non-center network computing simulation test platform, simulation is been conducted to test the performance and validity of the proposed algorithms. Experiment and analysis show that the proposed algorithms are suitable for large-scale, dynamic network computing environments, and able to maintain the credibility for networks without relying on central node, make a non-center network gradually evolve into an orderly, stable and reliable computing environment efficiently.

关键词： non-center network computing agent credibility evidence

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BIM技术在机电工程数字调试中的应用分析

工程与建设 2024年第1期38卷 181-182,229页

作者：徐小龙蒋隆张淇黄金友张艺才中建三局第一建设工程有限责任公司湖北武汉430040 中建三局第一建设安装有限公司湖北武汉430040

随着科学技术的不断进步,建筑信息模型(BIM)技术在工程中的应用越来越广泛。本文以实际工程项目为载体,介绍BIM技术在机电工程数字化调试中的应用,即利用BIM技术来建立整个建筑可视化的三维综合机电管线模型,进行机电管线的碰撞检测、调... 详细信息

随着科学技术的不断进步,建筑信息模型(BIM)技术在工程中的应用越来越广泛。本文以实际工程项目为载体,介绍BIM技术在机电工程数字化调试中的应用,即利用BIM技术来建立整个建筑可视化的三维综合机电管线模型,进行机电管线的碰撞检测、调试,分析BIM技术在机电管综中的重要性。分析结论可为在机电安装工程中强化BIM技术的应用起到更加积极的促进作用。

关键词： BIM技术机电安装工程数字调试应用

Impact of climate change on wheat yield and quality in the Yellow River Basin under RCP8.5 during 2020–2050

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Advances in Climate Change Research 2022年第3期13卷 397-407页

作者： xiao-xu long Hui JU Jian-Dong WANG Shi-Hong GONG Guang-Yong LI Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agriculture SciencesBeijing 100081China College of Water Resources&Civil Engineering China Agricultural UniversityBeijing 100083China Department of Irrigation and Drainage China Institute of Water Resources and Hydropower ResearchBeijing 100048China

Studying the impact of future climate change on the yield and quality of wheat in the Yellow River Basin(YRB)is both essential for rationalizing the utilization of climate resources and ensuring national food *** this study,we employed corrected refined meteorological grid data(30 km×30 km)generated by the Climate-Weather Research and Forecasting model under RCP8.5,coupled with the DSSAT-CERES-Wheat model to predict the impact of climate change on wheat phenology,yield,and grain nitrogen content(GNC)in the YRB from 2020 to *** to the type of wheat variety and planting management in the YRB,we designed five wheat ecological regions(I-V).The results show that from 2020 to 2050,the agro-meteorological resource,involving temperature,solar radiation,and precipitation,would have an overall increasing trend during the wheat growth seasons in the *** growth period of wheat was generally shortened by approximately 8 d,including 6 d less from sowing to anthesis,and 2 d less from anthesis to *** general,the predicted wheat yield showed a decreasing trend in the YRB,with an average reduction of 0.19%over the period from 2020 to 2050 compared with the baseline period from 1975 to 2005,and the spatial variation in wheat yield change was considerably *** the future,the Qing‒Zang Spring Wheat region(V)in the western part of the YRB would be the only region with a yield increase of 35.4%,whereas the Northern Spring Wheat region(I)in the northern part of the YRB would be the region exhibiting the greatest decrease of 9.9%.Moreover,compared with the baseline,the GNC would increase by an average of 2.3%in the YRB,with a significant increase in the southern and central parts during *** GNC increase in the Huang‒Huai Winter Wheat region(III)was the highest with a 12.5%increment,but the Qing‒Zang Spring Wheat region(V)is the only region where GNC would decline,with an average decrease of 18.9%.This study implies that wheat yield and GNC have a

关键词： Yellow river basin Climate change Wheat Yield Grain nitrogen content

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机器学习辅助图像识别红细胞抗氧化研究

分析化学 2024年第3期52卷 429-445页

作者：徐晓龙张成霖翁奇萍邓水连熊玉珍黎妍文秦传波曾军英刘长宇郏建波五邑大学环境与化学工程学院五邑大学电子与信息工程学院江门市人民医院

细胞形态是原始的生物学特征，可以提供有关细胞生理或病理状况的内在信息。与通过肉眼比对分析细胞形态的方法相比，基于人工智能（Artificial intelligence, AI）的图像识别方法有望提高分析速度和精度。本研究建立了细胞形态图像分... 详细信息

细胞形态是原始的生物学特征，可以提供有关细胞生理或病理状况的内在信息。与通过肉眼比对分析细胞形态的方法相比，基于人工智能（Artificial intelligence, AI）的图像识别方法有望提高分析速度和精度。本研究建立了细胞形态图像分割、识别和计数的氧化损伤分析模型，并将其用于研究红细胞抗氧化的动态过程。结果表明，以正常红细胞比率计，本模型获得了与经典生化指标一致的结果，表明本模型可用于分析红细胞氧化损伤程度。本方法无需细胞染色或细胞破碎等操作，可在2 h内获取结果；而且因为采用显微图像获取细胞形态信息，可实现细胞的实时监测。本模型有望拓展应用于环境毒理学有关细胞形态、细胞活性水平等方面的研究。

关键词：图像识别红细胞形态氧化损伤人工智能

基于微通道多向阀自动化快速提取DNA的研究

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五邑大学学报（自然科学版） 2024年第3期38卷 7-12页

作者：高英俊付立申徐晓龙吴文明五邑大学环境与化学工程学院广东江门529020 广东省科学院生物与医学工程研究所广东广州510316 五邑大学应用物理与材料学院广东江门529020

核酸的高效分离与纯化对于下游分子诊断具有至关重要的影响.本研究基于磁珠法提取原理设计出快速、自动化核酸提取系统,利用步进电机和注射泵组成的移液装置通过微通道连接多向电磁阀完成核酸裂解、洗涤、洗脱、纯化,通过大鼠主动脉内... 详细信息

核酸的高效分离与纯化对于下游分子诊断具有至关重要的影响.本研究基于磁珠法提取原理设计出快速、自动化核酸提取系统,利用步进电机和注射泵组成的移液装置通过微通道连接多向电磁阀完成核酸裂解、洗涤、洗脱、纯化,通过大鼠主动脉内皮细胞进行核酸提取和扩增,对核酸加热裂解时间进行优化.结果表明,当裂解时间大于4 min时,核酸纯化效果最好,磁珠回收率可达96.5%,紫外吸收光比值大于1.8,同时整个自动化提取仅需8 min.通过微通道多向阀与核酸提取技术纯化后的核酸可直接用于扩增实验,且与手动提取相比聚合酶链式反应的Ct值起跳更早,有利于后续集成核酸检测一体化系统.

关键词：样品预处理核酸提取微通道磁珠法

制备条件对脱硝脱二噁英V2O5-CeO_(2)/TiO_(2)催化剂协同性能的影响

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安徽化工 2024年第1期50卷 51-53,61页

作者：许晓龙童翠香蔡佳凤王光应安徽元琛环保科技股份有限公司安徽合肥230011

采用等体积浸渍的方法制备V2O5-CeO_(2)/TiO_(2)催化剂,考查了V2O_(5)/CeO_(2)比、负载顺序、焙烧温度、反应空速对催化剂协同脱硝脱二噁英性能的影响。结果表明,所制备的催化剂活性组分在载体表面分散均匀。采用共同浸渍法制备,V2O_(5)... 详细信息

采用等体积浸渍的方法制备V2O5-CeO_(2)/TiO_(2)催化剂,考查了V2O_(5)/CeO_(2)比、负载顺序、焙烧温度、反应空速对催化剂协同脱硝脱二噁英性能的影响。结果表明,所制备的催化剂活性组分在载体表面分散均匀。采用共同浸渍法制备,V2O_(5)/CeO_(2)质量比为1∶3,焙烧温度为550℃的催化剂协同脱硝脱二氯苯性能最佳,在200℃反应温度下脱硝率为93%,二氯苯的脱除率达到90%。

关键词：脱硝脱二噁英钒铈钛催化剂