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Research on optimal intelligent routing algorithm for IoV with machine learning and smart contract
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作者 Baofeng Ji mingkun zhang +4 位作者 Ling Xing Xiaoli Li Chunguo Li Congzheng Han Hong Wen 《Digital Communications and Networks》 SCIE CSCD 2023年第1期47-55,共9页
The huge increase in the communication network rate has made the application fields and scenarios for vehicular ad hoc networks more abundant and diversified and proposed more requirements for the efficiency and quali... The huge increase in the communication network rate has made the application fields and scenarios for vehicular ad hoc networks more abundant and diversified and proposed more requirements for the efficiency and quality of data transmission.To improve the limited communication distance and poor communication quality of the Internet of Vehicles(IoV),an optimal intelligent routing algorithm is proposed in this paper.Combined multiweight decision algorithm with the greedy perimeter stateless routing protocol,designed and evaluated standardized function for link stability.Linear additive weighting is used to optimize link stability and distance to improve the packet delivery rate of the IoV.The blockchain system is used as the storage structure for relay data,and the smart contract incentive algorithm based on machine learning is used to encourage relay vehicles to provide more communication bandwidth for data packet transmission.The proposed scheme is simulated and analyzed under different scenarios and different parameters.The experimental results demonstrate that the proposed scheme can effectively reduce the packet loss rate and improve system performance. 展开更多
关键词 IoV Machine learning Smart contract Routing algorithm GPSR Relay transmission
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Decision Analysis on IoV Routing Transmission and Energy Efficiency Optimization Algorithm with AmBC
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作者 Baofeng Ji mingkun zhang +1 位作者 Weixing Wang Song Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2661-2673,共13页
The improvement of the quality and efficiency of vehicle wireless network data transmission is always a key concern in the Internet of Vehicles(IoV).Routing transmission solved the limitation of transmission distance ... The improvement of the quality and efficiency of vehicle wireless network data transmission is always a key concern in the Internet of Vehicles(IoV).Routing transmission solved the limitation of transmission distance to a certain extent.Traditional routing algorithm cannot adapt to complex traffic environment,resulting in low transmission efficiency.In order to improve the transmission success rate and quality of vehicle network routing transmission,make the routing algorithm more suitable for complex traffic environment,and reduce transmission power consumption to improve energy efficiency,a comprehensive optimized routing transmission algorithm is proposed.Based on the routing transmission algorithm,an optimization algorithmbased on road condition,vehicle status and network performance is proposed to improve the success rate of routing transmission in the IoV.Relative distance difference and density are used as decision-making indicators to measure Road Side Unit(RSU)assisted transmission.And the Ambient backscatter communication(AmBC)technology and energy collection are used to reduce the energy consumption of routing relay transmission.An energy collection optimization algorithm is proposed to optimize the energy efficiency of AmBC and improve the energy efficiency of transmission.Simulation results show that the proposed routing optimization algorithm can effectively improve the success rate of packet transmission in vehicular ad hoc networks(VANETs),and theAmBC optimization algorithmcan effectively reduce energy consumption in the transmission process.The proposed optimization algorithm achieves comprehensive optimization of routing transmission performance and energy efficiency. 展开更多
关键词 IoV routing algorithm AmBC RELAY TRANSMISSION
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Impacts of hydrogen annealing on the carrier lifetimes in p-type 4H-SiC after thermal oxidation
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作者 张锐军 洪荣墩 +11 位作者 韩景瑞 丁雄杰 李锡光 蔡加法 陈厦平 傅德颐 林鼎渠 张明昆 吴少雄 张宇宁 吴正云 张峰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期60-65,共6页
Thermal oxidation and hydrogen annealing were applied on a 100μm thick Al-doped p-type 4H-Si C epitaxial wafer to modulate the minority carrier lifetime,which was investigated by microwave photoconductive decay(μ-PC... Thermal oxidation and hydrogen annealing were applied on a 100μm thick Al-doped p-type 4H-Si C epitaxial wafer to modulate the minority carrier lifetime,which was investigated by microwave photoconductive decay(μ-PCD).The minority carrier lifetime decreased after each thermal oxidation.On the contrary,with the hydrogen annealing time increasing to3 hours,the minority carrier lifetime increased from 1.1μs(as-grown)to 3.14μs and then saturated after the annealing time reached 4 hours.The increase of surface roughness from 0.236 nm to 0.316 nm may also be one of the reasons for limiting the further improvement of the minority carrier lifetimes.Moreover,the whole wafer mappings of minority carrier lifetimes before and after hydrogen annealing were measured and discussed.The average minority carrier lifetime was up to 1.94μs and non-uniformity of carrier lifetime reached 38%after 4-hour hydrogen annealing.The increasing minority carrier lifetimes could be attributed to the double mechanisms of excess carbon atoms diffusion caused by selective etching of Si atoms and passivation of deep-level defects by hydrogen atoms. 展开更多
关键词 4H-SIC carrier lifetime hydrogen annealing
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乳腺浸润性微乳头状癌预后影响因素分析与模型构建 被引量:1
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作者 张明坤 王哲 +2 位作者 杨柳 侯兰 张聚良 《中国肿瘤临床》 CAS CSCD 北大核心 2021年第12期624-630,共7页
目的:对比分析中国和美国乳腺浸润性微乳头状癌(invasive micropapillary carcinoma,IMPC)的病理特征和预后影响因素,并预测乳腺IMPC患者预后。方法:回顾性分析2006年7月至2015年7月83例于中国人民解放军空军军医大学西京医院收治的乳腺... 目的:对比分析中国和美国乳腺浸润性微乳头状癌(invasive micropapillary carcinoma,IMPC)的病理特征和预后影响因素,并预测乳腺IMPC患者预后。方法:回顾性分析2006年7月至2015年7月83例于中国人民解放军空军军医大学西京医院收治的乳腺IMPC患者临床资料,收集2010年3月至2015年3月415例美国国立癌症研究所的SEER数据库中诊断为乳腺IMPC患者资料,并对中国和美国患者的临床病理特征进行对比。进行单因素及Cox比例回归模型多因素和Fine-Gray竞争风险模型分析,并构建列线图模型预测患者的总生存(overall survival,OS)率和癌症特异生存(cancer-specific survival,CSS)率。对模型进行内部及外部验证,通过临床决策曲线分析评价模型的临床获益和应用价值。结果:对建模集和验证集的年龄、肿瘤位置、手术方式、是否为第一原发肿瘤、T分期进行比较,差异具有统计学意义(P<0.05)。单因素及Cox比例回归模型多因素和Fine-Gray竞争风险模型分析结果显示,年龄、N分期、M分期以及分子分型与乳腺IMPC预后相关(P<0.05),将这些因素纳入并建立OS和CSS的列线图预测模型。OS和CSS模型中建模集C-index分别为0.85和0.79,验证集外部验证C-index分别为0.72和0.70,bootstrap法内部验证C-index分别为0.81和0.74。校准曲线显示列线图预测的生存率与实际生存率接近,临床决策曲线分析显示模型的临床获益及应用价值较高。结论:列线图能准确预测中国及美国乳腺IMPC患者的预后,为临床的诊疗提供科学依据。 展开更多
关键词 乳腺浸润性微乳头状癌 SEER 数据库 预后 列线图
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Multi-scale molecular dynamics simulations and applications on mechanosensitive proteins of integrins
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作者 吕守芹 丁奇寒 +1 位作者 张明焜 龙勉 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第3期1-8,共8页
Molecular dynamics simulation(MDS)is a powerful technology for investigating evolution dynamics of target proteins,and it is used widely in various fields from materials to biology.This mini-review introduced the prin... Molecular dynamics simulation(MDS)is a powerful technology for investigating evolution dynamics of target proteins,and it is used widely in various fields from materials to biology.This mini-review introduced the principles,main preforming procedures,and advances of MDS,as well as its applications on the studies of conformational and allosteric dynamics of proteins especially on that of the mechanosensitive integrins.Future perspectives were also proposed.This review could provide clues in understanding the potentiality of MD simulations in structure–function relationship investigation of biological proteins. 展开更多
关键词 molecular dynamics simulations mechanosensitive protein allosteric dynamics INTEGRIN
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柔性PDA薄膜阵列用于双模光学检测VOC标志物气体 被引量:2
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作者 徐华 安远 +2 位作者 张明坤 李佳佳 顾忠泽 《中国科学:化学》 CAS CSCD 北大核心 2020年第1期135-142,共8页
本研究以亲油性的双面胶作为基底,利用滴涂二乙炔单体结合紫外光聚合来制备均匀的聚二乙炔(PDA)薄膜,通过荧光和颜色两种信号变化模式(即"双模光学检测")研究了PDA薄膜对VOC气体的响应性,发现制备的PDA薄膜在2 min内就可以实... 本研究以亲油性的双面胶作为基底,利用滴涂二乙炔单体结合紫外光聚合来制备均匀的聚二乙炔(PDA)薄膜,通过荧光和颜色两种信号变化模式(即"双模光学检测")研究了PDA薄膜对VOC气体的响应性,发现制备的PDA薄膜在2 min内就可以实现明显的荧光和颜色变化,有效解决了目前PDA薄膜在VOC气体检测方面存在响应速度慢、薄膜均一性差等问题.此外,为解决单一PDA薄膜的交叉响应性问题,本研究制备了四种不同的基于双面胶基底的PDA薄膜,并将制备的4种PDA薄膜集成到一片PDMS薄膜基底上来构建柔性的传感阵列,利用阵列的颜色变化结合模式识别技术,实现了对8种VOC气体的快速、灵敏区分.进一步将制备的PDA薄膜阵列用于健康人、模拟糖尿病及肾病患者呼出气体中VOC标志物的辨别和分析研究,发现可以将三类人的呼出气体清晰地区分,说明了该阵列在呼气疾病诊断中的应用前景.与目前报道的PDA薄膜阵列相比,本研究中基于双面胶基底的PDA薄膜阵列具有气体响应速度快、灵敏性高、柔韧性好、制备工艺简单、成本低、易于大规模制备等优点,有望用于实VOC气体检测研究中. 展开更多
关键词 PDA薄膜阵列 VOC气体检测 荧光 颜色 疾病诊断
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通过镓离子束辐照调控单层MoS_(2)晶体管的阈值电压
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作者 唐保山 赵云山 +7 位作者 周昌杰 张明昆 朱会丽 李毅达 梁锦锋 帅浩 龚浩 杨伟锋 《Science China Materials》 SCIE EI CAS CSCD 2022年第3期741-747,共7页
对原子层厚度二维(2D)过渡金属硫化物(TMDCs)电子属性的调控是实现其新型光电和电子器件应用的关键.本文采用聚焦低能量镓离子束辐照超薄二硫化钼,通过缺陷工程实现了原子层级的位点缺陷调控.研究发现二硫化钼表面缺陷可以通过精确控制... 对原子层厚度二维(2D)过渡金属硫化物(TMDCs)电子属性的调控是实现其新型光电和电子器件应用的关键.本文采用聚焦低能量镓离子束辐照超薄二硫化钼,通过缺陷工程实现了原子层级的位点缺陷调控.研究发现二硫化钼表面缺陷可以通过精确控制镓离子束的能量和剂量来实现低损伤的镓掺杂.此外,在镓离子注入后,单层二硫化钼晶体管的阈值电压实现了超过70 V的迁移.第一性原理计算证实镓杂质离子在单层二硫化钼的费米能级附近引入一个位于价带顶0.25 eV的浅缺陷能级.这种可控和便捷的缺陷工程方法实现了原子层深度的复杂图样区域性掺杂,进而调控超薄二维半导体的电学性能,为实现高性能的新一代光电和电子器件奠定了基础. 展开更多
关键词 缺陷工程 阈值电压 原子层 费米能级 第一性原理计算 离子束辐照 二硫化钼 二维半导体
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