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AH-FBG法用于毛细水运移规律的温度效应研究
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作者 辛雨凌 徐成华 +3 位作者 孙梦雅 刘瑾 戴正彬 井淼 《天津大学学报(自然科学与工程技术版)》 北大核心 2026年第1期31-40,共10页
毛细水运移作为非饱和土体水分运移的重要形式,其动态特征直接影响土体的力学性质,并与多种地质灾害、环境岩土问题密切相关.地下水位以上的土体温度分布往往存在差异,进而对毛细水运移速率产生影响.为了探究毛细水运移规律的温度效应,... 毛细水运移作为非饱和土体水分运移的重要形式,其动态特征直接影响土体的力学性质,并与多种地质灾害、环境岩土问题密切相关.地下水位以上的土体温度分布往往存在差异,进而对毛细水运移速率产生影响.为了探究毛细水运移规律的温度效应,本研究利用主动加热光纤布拉格光栅(AH-FBG)法开展室内模型试验,在定水头条件下,通过控制加热桶与常温桶的温度变量监测土体中毛细水运移过程,并对不同温度条件下土体的体积含水率分布变化进行对比,分析温度效应对毛细水运移的影响.研究结果表明:在一定时间内,毛细水上升高度随时间增加而升高,湿润峰出现的位置标志着该时刻水分运移的最远位置;土体温度升高对毛细水运移具有促进影响,土体温度越高,毛细水上升同一高度所需的时间越短,毛细水上升速率越高;湿润锋界面作为状态界面,在运移过程中具有动态变化特性,温度升高会显著促进湿润峰界面的运移速率;毛细水湿润锋界面变化及其温度效应与外界环境条件紧密相关,是工程建设中不可忽视的运动与状态界面. 展开更多
关键词 毛细水运移 主动加热光纤布拉格光栅法 体积含水率 湿润锋 温度效应 状态界面
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高强钢AH36薄板随焊热拉伸焊接失稳控制及其机理
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作者 易斌 刘延斌 +3 位作者 付玲 薛丁琪 柳志诚 王江超 《中国机械工程》 北大核心 2025年第12期3030-3039,共10页
高强钢AH36薄板焊接失稳变形严重影响制造精度,且难以通过焊后矫形手段完全消除。随焊热拉伸工艺是一种有效控制薄板焊接失稳变形的方法。以感应加热为辅助热源搭建随焊热拉伸焊接试验平台,进行高强钢AH36薄板常规对接焊和随焊热拉伸工... 高强钢AH36薄板焊接失稳变形严重影响制造精度,且难以通过焊后矫形手段完全消除。随焊热拉伸工艺是一种有效控制薄板焊接失稳变形的方法。以感应加热为辅助热源搭建随焊热拉伸焊接试验平台,进行高强钢AH36薄板常规对接焊和随焊热拉伸工艺试验,待试板冷却至室温后,通过三坐标测量仪测量接头变形,在常规焊接下最大相对面外变形为23.88 mm,随焊热拉伸下减小至13.68 mm。随后建立接头有限元模型,进行热-弹-塑性有限元分析,计算得到的结果与测量结果十分吻合,且通过调整热拉伸温度,接头最大相对面外变形减小至4.42 mm。最后基于固有应变理论分析了高强钢AH36薄板焊接失稳变形产生的原因以及随焊热拉伸工艺的控制机理:辅助热源形成的热拉伸作用改变了母材对焊缝的拘束程度,导致升温过程中产生了更小的压缩塑性应变,而冷却过程中产生了更大的拉伸塑性应变,使得焊缝处固有应变减小,纵向收缩力减小26.4%;瞬时变形降低使得横向固有弯曲力矩减小95.2%,减小了失稳产生的初始扰动,进一步控制了薄板焊接失稳变形。 展开更多
关键词 随焊热拉伸 固有应变 焊接失稳变形 机理分析 有限元计算 高强钢ah36
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Ce对AH36钢海洋环境中腐蚀行为的影响 被引量:3
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作者 李想 刘香军 +2 位作者 杨昌桥 任慧平 刘玉宝 《中国冶金》 北大核心 2025年第5期106-118,共13页
海洋环境下,船板钢易发生腐蚀,严重危害材料的服役安全。为了研究稀土Ce对AH36船板钢在海洋环境中耐腐蚀性能的影响,采用SEM、XRD、EPMA及电化学测试等手段分析了Ce对AH36钢中夹杂物的影响及其在模拟海洋环境下的腐蚀行为。研究结果显示... 海洋环境下,船板钢易发生腐蚀,严重危害材料的服役安全。为了研究稀土Ce对AH36船板钢在海洋环境中耐腐蚀性能的影响,采用SEM、XRD、EPMA及电化学测试等手段分析了Ce对AH36钢中夹杂物的影响及其在模拟海洋环境下的腐蚀行为。研究结果显示,添加Ce后,钢中的Al2O3、MnS、TiN夹杂物转变为椭球形的Ce-O、Ce-Ti-N-O-S夹杂物,钢中夹杂物的尺寸由2.5~6.0μm减小至1~2μm;当Ce的质量分数为0.009%、0.034%时,试验钢中夹杂物的数量密度从49mm^(-2)分别提高至54mm^(-2)和72mm^(-2),尺寸小于5μm的夹杂物所占比例从67%分别提高至82%和76%。质量分数为3.5%NaCl溶液浸泡试验结果表明,Ce可以提高α-FeOOH和Fe_(3)O_(4)在腐蚀产物中的占比;Ce的质量分数为0.009%和0.034%时,腐蚀产物中α-FeOOH和Fe_(3)O_(4)的质量分数之和与γ-FeOOH的质量分数之比(α^(*)/γ^(*))较未添加Ce时的1.09分别增大至2.27和1.64;浸泡21d时,Ce的质量分数为0.009%和0.034%,试验钢的腐蚀电流密度由未添加Ce时的2.652A/cm^(2)分别减小至2.127、2.209A/cm^(2);Ce的质量分数为0.009%时AH36钢的耐蚀性较好。 展开更多
关键词 稀土Ce ah36船板钢 夹杂物 腐蚀产物 X射线衍射
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不同充氢条件下AH36钢的氢脱附及氢脆敏感性 被引量:1
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作者 陈翠 李维娟 +4 位作者 张大征 庞启航 潘越 马祉怡 许廷峰 《金属热处理》 北大核心 2025年第7期151-158,共8页
通过氢微印技术、热脱附谱分析、慢应变速率拉伸试验,结合扫描电镜和透射电镜,探究了充氢条件为50 mA/cm^(2)-24 h、100 mA/cm^(2)-2 h、100 mA/cm^(2)-24 h时AH36钢板中的氢脱附行为及氢脆敏感性。结果表明,充氢后,氢原子主要存在于珠... 通过氢微印技术、热脱附谱分析、慢应变速率拉伸试验,结合扫描电镜和透射电镜,探究了充氢条件为50 mA/cm^(2)-24 h、100 mA/cm^(2)-2 h、100 mA/cm^(2)-24 h时AH36钢板中的氢脱附行为及氢脆敏感性。结果表明,充氢后,氢原子主要存在于珠光体中渗碳体/铁素体相界和铁素体晶界处,晶内分布较少,珠光体中渗碳体/铁素体相界、铁素体晶界和晶内的位错显著增多,并且铁素体晶界宽化;在200℃以下出现一个氢的热脱附峰,其最大脱附速率为0.012~0.063μg/(g·min),脱附累积总量为0.48~4.47μg/g。随着充氢电流密度和充氢时间的增加,氢原子的最大脱附速率和脱附总量逐渐减小;屈服平台长度逐渐缩短,屈服强度变化不超过1.16%,抗拉强度由483.9 MPa降至438.1 MPa、断后伸长率由55.8%降至19.4%,氢脆敏感性显著增加;拉伸断口缩颈现象逐渐消失,形貌均由韧窝向河流状花样转变,断裂机制由韧性断裂逐渐转变成脆性断裂。 展开更多
关键词 ah36钢 电化学充氢 氢微印技术 热脱附分析 氢脆敏感性
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生物陶瓷充填材料和AH-plus糊剂对成人慢性根尖周炎根管治疗疗效及血清骨保护素RANKL的影响 被引量:7
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作者 陈珍珍 刘刚 朱坤鹍 《河北医学》 2025年第1期91-96,共6页
目的:探究生物陶瓷充填材料(iRoot SP)和AH-plus糊剂对成人慢性根尖周炎(CAP)根管治疗疗效及血清骨保护素(OPG)、核因子-κB受体活化因子配体(RANKL)的影响。方法:选取2021年1月至2023年12月期间在本院行根管治疗的135例成人CAP患者作... 目的:探究生物陶瓷充填材料(iRoot SP)和AH-plus糊剂对成人慢性根尖周炎(CAP)根管治疗疗效及血清骨保护素(OPG)、核因子-κB受体活化因子配体(RANKL)的影响。方法:选取2021年1月至2023年12月期间在本院行根管治疗的135例成人CAP患者作为研究对象,采用电脑随机数字摇号法将其分为iRoot SP组(iRoot SP行单尖充填,n=68)和AH-plus组(AH-plus热压胶充填,n=67)。比较iRoot SP组和AH-plus组治疗即刻填充情况,治疗7d(T1)疼痛分级,T1、3个月(T2)、6个月(T3)疗效,治疗前(T0)、T1、T2、T3旧根尖周指数(old-periapical index,O-PAI)、血清OPG、RANKL及RANKL/OPG。结果:iRoot SP组适充率为98.53%,高于AH-plus组的89.55%,差异有统计学意义(P<0.05);iRoot SP组疼痛率下降幅度大于AH-plus组疼痛率下降幅度,差异有统计学意义(P<0.05);iRoot SP组T1、T2、T3时间点有效率分别为98.53%、95.59%、91.18%,均高于AH-plus组的89.55%、85.07%、79.10%,差异均有统计学意义(P<0.05);O-PAI、OPG、RANKL、RANKL/OPG组间效应、时间效应、交互效应均有差异统计学意义(P<0.05),且iRoot SP组O-PAI下降幅度、血清OPG上升幅度、RANKL与RANKL/OPG下降幅度均大于AH-plus组,差异均有统计学意义(P<0.05)。结论:相较于AH-plus糊剂作为填充物行根管治疗,iRoot SP作为填充物行根管治疗成人CAP效果更佳,可显著下调患者疼痛分级、RANKL表达及RANKL/OPG值,提高适充率和血清OPG表达,优化牙周病损。 展开更多
关键词 生物陶瓷充填材料 ah-PLUS糊剂 慢性根尖周炎 骨保护素 核因子-ΚB受体活化因子配体
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夹杂物演化对AH36钢大线能量焊接热影响区韧性影响研究
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作者 赵立冬 赵和明 +4 位作者 李维娟 于浩 王堤鹤 白瑞 庞启航 《热加工工艺》 北大核心 2025年第23期160-166,共7页
采用原位观察和OTS分析,分析了焊接过程不同热输入下AH36钢焊接热影响区夹杂物形成、形貌及元素分布规律,揭示了夹杂物演化对针状铁素体形核,以及焊接热影响区韧性的影响机制。结果表明:随着热输入的增加,试验钢冲击功先增大后减小,热... 采用原位观察和OTS分析,分析了焊接过程不同热输入下AH36钢焊接热影响区夹杂物形成、形貌及元素分布规律,揭示了夹杂物演化对针状铁素体形核,以及焊接热影响区韧性的影响机制。结果表明:随着热输入的增加,试验钢冲击功先增大后减小,热输入为550 kJ/cm时,冲击功数值较高,韧性较好。试验钢焊接热影响区显微组织主要由针状铁素体(IAF)和块状铁素体(PF)构成。试验钢的奥氏体晶粒尺寸为85~200μm,能够促进针状铁素体形核,晶内针状铁素体相较于晶界针状铁素体对提高热影响区韧性的贡献更大。基于贫锰区理论与惰性界面机理共同作用,试验钢热影响区晶内夹杂物诱发针状铁素体形核是热影响区韧性良好的原因。试验钢夹杂物可以分为两类:一类是尺寸为1.5~2.5μm夹杂物数量较多;另一类是尺寸为2~4μm的复合物夹杂物(Al、Mg、Ti、Ca、Si)-O或(Al、Mg、Ti)-O。二者共存时易发生夹杂物诱导晶内针状铁素体形核,与多边形铁素体均匀分布,这是550 kJ/cm试验钢焊接热影响区韧性良好的原因。 展开更多
关键词 ah36钢 大线能量焊接 原位观察 针状铁素体
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280 Ah浸没式液冷电池模组流动传热策略研究
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作者 郭鹏宇 张明杰 +5 位作者 程宜风 马俊华 陈浩 李昌豪 魏斌 巨星 《储能科学与技术》 北大核心 2025年第12期4567-4582,共16页
针对传统风冷和液冷板式储能电池模组存在的模组温升过大和电池上下温度不均匀问题,设计了1并5串的280 Ah浸没式液冷电池模组,开展了电池模组流动策略仿真与实验研究。研究结果表明:在模组设计及冷却液进出口选择方面,通过对比底板式和... 针对传统风冷和液冷板式储能电池模组存在的模组温升过大和电池上下温度不均匀问题,设计了1并5串的280 Ah浸没式液冷电池模组,开展了电池模组流动策略仿真与实验研究。研究结果表明:在模组设计及冷却液进出口选择方面,通过对比底板式和侧板式电池模组的4种冷却液进出口方式,发现采用底板式左下进右上出方式的电池模组的热性能最好;在自然对流条件下电池模组均温性分析方面,发现半浸没无法改善电池本身的温度均匀性,全浸没具有最好的单体及模组均温性;在冷却液进口流量方面,发现强制流动能大幅降低模组温升,模组最高温度、温差及温升均在冷却液流量为6 L/min时出现极小值,分别为30.55℃、4.15℃及5.59℃。通过分析对流换热系数h和冷却液带走热量Q_(f),发现在强制流动条件下存在3个“流量区”,其中在中等流量区存在一个“最佳流量值”,使得在该流量下电池模组的热性能最好。综上,本工作研究的浸没式液冷电池模组最佳流动策略为:采用底板式左下进右上出的进出口方式,电池模组全浸没且进口流量设置为6 L/min。 展开更多
关键词 280 ah锂离子电池 浸没式液冷 模组设计 流动策略
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船用AH36/316L不锈钢复合板焊接修复研究
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作者 杨继国 李斌 +3 位作者 李伟 曾周燏 石寅辉 邹家生 《江苏科技大学学报(自然科学版)》 2025年第2期44-50,共7页
由于船用AH36/316L不锈钢金属复合板具有相对突出的性价比,故被广泛应用于船舶领域.但因为不锈钢复合板的复层和基层的理化性能和化学成分有较大差异,导致在焊接过程中复层焊缝难免受到基层母材和基层焊缝的影响出现焊接缺陷等问题.为... 由于船用AH36/316L不锈钢金属复合板具有相对突出的性价比,故被广泛应用于船舶领域.但因为不锈钢复合板的复层和基层的理化性能和化学成分有较大差异,导致在焊接过程中复层焊缝难免受到基层母材和基层焊缝的影响出现焊接缺陷等问题.为了研究焊接修复后的焊接接头是否还能满足相关标准要求,采用药芯焊丝电弧焊(flux-cored arc welding,FCAW)焊接,焊材为GFS-309MoL和GFS-316L对船用AH36/316L不锈钢复合板的过渡层和复层焊缝进行1~2次焊接修复试验,对修复后接头的微观组织、力学性能和耐蚀性能进行分析.结果表明:采用FCAW焊接方法对AH36/316L不锈钢复合板进行1~2次修复并不影响焊接接头的力学性能;1~2次焊接修复后复层焊缝物相组成主要是γ相;但经过2次修复后,不锈钢复层侧焊缝的铁素体含量增大,晶间腐蚀试验在熔合线处发现了断裂和宏观裂纹,扫描电镜观察断口形貌后,断裂机制为准脆性解理断裂,这与熔合线处的C元素较大范围内含量明显升高有关.故采用FCAW焊接方法对AH36/316L不锈钢复合板复层焊缝进行焊接修复时,不推荐进行2次焊接修复. 展开更多
关键词 船用ah36/316L不锈钢复合板 焊接修复 力学性能 腐蚀性能
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C-Root SP单尖充填技术与AH Plus热牙胶充填技术的临床疗效分析
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作者 雷凡 孙红 +2 位作者 徐倩 端木婷婷 陈亮 《皖南医学院学报》 2025年第4期365-367,381,共4页
目的:探讨C-Root SP单尖充填技术和AH Plus糊剂联合热牙胶充填技术在根管治疗中的效果。方法:选择芜湖市第一人民医院口腔科2024年1~9月符合纳入标准的164例根管治疗患者,81例采用C-Root SP单尖充填技术,83例采用AH Plus糊剂联合热牙胶... 目的:探讨C-Root SP单尖充填技术和AH Plus糊剂联合热牙胶充填技术在根管治疗中的效果。方法:选择芜湖市第一人民医院口腔科2024年1~9月符合纳入标准的164例根管治疗患者,81例采用C-Root SP单尖充填技术,83例采用AH Plus糊剂联合热牙胶充填技术,比较两组根管充填时间、根管充填质量(X线片观察糊剂是否超充)及术后24 h、1周后疼痛程度。结果:C-Root SP组根管充填时间[(46.94±12.30)s]低于AH Plus组[(124.88±30.36)s],P<0.001。C-Root SP组患者24 h内疼痛发生率(4.94%)低于AH Plus组(16.88%),P<0.05。两组根管充填封闭剂充填质量和治疗术后1周疼痛差异无统计学意义(P>0.05)。结论:采用C-Root SP单尖充填技术和AH Plus糊剂联合热牙胶充填技术进行根管治疗均可取得一定临床疗效,但C-Root SP单尖充填术后短期疼痛程度缓解效果较好且能有效缩短根管治疗时间。 展开更多
关键词 C-Root SP ah Plus 根管封闭剂 根管治疗
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焊接材料组合对AH36/316L不锈钢复合板焊接接头性能的影响
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作者 李斌 曾周燏 +3 位作者 杨雪冰 石寅辉 李伟 邹家生 《江苏科技大学学报(自然科学版)》 2025年第5期78-84,共7页
AH36/316L不锈钢复合板兼具碳钢良好的力学性能和不锈钢优异的耐腐蚀性能,目前是化学品船建造领域的研究热点之一,但其焊接工艺的复杂性限制了该类型材料的应用.文中针对(7.5 mm+3 mm)的AH36/316L不锈钢复合板开展药芯焊丝气体保护焊试... AH36/316L不锈钢复合板兼具碳钢良好的力学性能和不锈钢优异的耐腐蚀性能,目前是化学品船建造领域的研究热点之一,但其焊接工艺的复杂性限制了该类型材料的应用.文中针对(7.5 mm+3 mm)的AH36/316L不锈钢复合板开展药芯焊丝气体保护焊试验,分别采用GFL-71(基层焊接材料)+GFL-309MoL(过渡层+复层焊接材料)、GFL-71(基层焊接材料)+GFL-316L(过渡层+复层焊接材料)、GFL-309MoL(基层、过渡层和复层焊接材料)以及GFL-316L(基层、过渡层和复层焊接材料)4种焊接材料组合方式完成不锈钢复合板基层、过渡层和复层的焊接,并重点探究不同的焊接材料组合对焊接接头力学性能和腐蚀性能的影响.研究结果表明:当基层、过渡层和复层均采用GFL-309MoL焊丝时,焊接接头的力学性能、晶间腐蚀性能和电化学腐蚀性能最佳,此时接头不锈钢侧的焊缝显微组织主要由奥氏体和铁素体组成.当基层采用GFL-71焊丝、过渡层和复层采用GFL-316L焊丝时,焊接接头晶间腐蚀弯曲后在熔合线处发现了肉眼可见的裂纹,不能满足使用要求. 展开更多
关键词 ah36/316L不锈钢复合板 焊接材料组合 药芯焊丝气体保护焊 力学性能 腐蚀性能
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C-Root SP单尖法和AH Plus热牙胶垂直加压法在根管充填中的应用效果比较
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作者 吕坤 程艺源 +3 位作者 鲁梦婷 鲁建洲 陈佳颖 孟祥勇 《中国当代医药》 2025年第23期92-95,共4页
目的对比C-Root SP单尖充填与AH Plus垂直加压充填在慢性牙髓炎及慢性根尖周炎中的疗效。方法选取2023年4月至2024年4月在湖州市第一人民医院口腔牙体牙髓科接受治疗的74例慢性牙髓炎及慢性根尖周炎患者作为研究对象,采用随机数字表法... 目的对比C-Root SP单尖充填与AH Plus垂直加压充填在慢性牙髓炎及慢性根尖周炎中的疗效。方法选取2023年4月至2024年4月在湖州市第一人民医院口腔牙体牙髓科接受治疗的74例慢性牙髓炎及慢性根尖周炎患者作为研究对象,采用随机数字表法分为研究组(单尖技术充填C-Root SP)和对照组(热牙胶垂直加压充填AH Plus),每组37例。观察比较患者根管充填质量、术后7 d疼痛评估和术后半年临床疗效。结果研究组治疗后根管超填率高于对照组,恰填率低于对照组,差异有统计学意义(P<0.05);两组的欠填率比较,差异无统计学意义(P>0.05)。两组术后7 d的疼痛情况以及术后6个月的治疗反应率比较,差异均无统计学意义(P>0.05)。结论C-Root SP联合单尖技术充填后的超填概率高于AH Plus联合热牙胶垂直加压充填,术后的临床疗效有效率均较高,两种治疗方案均可较好地完成根管充填。 展开更多
关键词 C-Root SP ah Plus 根管封闭剂 根管充填 根管治疗
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Multi-Factor Authentication for Keyless Entry Systems: An Innovative Approach to Automotive Security
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作者 Danilo Brito Shakour Abuzneid 《Journal of Information Security》 2025年第1期78-100,共23页
Car manufacturers aim to enhance the use of two-factor authentication (2FA) to protect keyless entry systems in contemporary cars. Despite providing significant ease for users, keyless entry systems have become more s... Car manufacturers aim to enhance the use of two-factor authentication (2FA) to protect keyless entry systems in contemporary cars. Despite providing significant ease for users, keyless entry systems have become more susceptible to appealing attacks like relay attacks and critical fob hacking. These weaknesses present considerable security threats, resulting in unauthorized entry and car theft. The suggested approach combines a conventional keyless entry feature with an extra security measure. Implementing multi-factor authentication significantly improves the security of systems that allow keyless entry by reducing the likelihood of unauthorized access. Research shows that the benefits of using two-factor authentication, such as a substantial increase in security, far outweigh any minor drawbacks. 展开更多
关键词 MFA Keyless Entry Systems Automotive Security Biometric authentication
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Endogenous Security Through AI-Driven Physical-Layer Authentication for Future 6G Networks
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作者 MENG Rui FAN Dayu +2 位作者 XU Xiaodong LYU Suyu TAO Xiaofeng 《ZTE Communications》 2025年第1期18-29,共12页
To ensure the access security of 6G,physical-layer authentication(PLA)leverages the randomness and space-time-frequency uniqueness of the channel to provide unique identity signatures for transmitters.Furthermore,the ... To ensure the access security of 6G,physical-layer authentication(PLA)leverages the randomness and space-time-frequency uniqueness of the channel to provide unique identity signatures for transmitters.Furthermore,the introduction of artificial intelligence(AI)facilitates the learning of the distribution characteristics of channel fingerprints,effectively addressing the uncertainties and unknown dynamic challenges in wireless link modeling.This paper reviews representative AI-enabled PLA schemes and proposes a graph neural network(GNN)-based PLA approach in response to the challenges existing methods face in identifying mobile users.Simulation results demonstrate that the proposed method outperforms six baseline schemes in terms of authentication accuracy.Furthermore,this paper outlines the future development directions of PLA. 展开更多
关键词 physical-layer authentication artificial intelligence wireless security intelligent authentication
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iRoot SP单尖充填与AH Plus热牙胶充填根管的充填质量、术后疼痛及临床疗效比较
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作者 李亚伟 《实用临床医学(江西)》 2025年第4期52-56,共5页
目的探究并比较iRoot SP单尖充填、AH Plus热牙胶充填技术的充填质量、对术后疼痛的影响与整体治疗效果。方法将84例行根管治疗患者随机分对照组与观察组,各42例。对照组采用AH Plus热牙胶充填,观察组采用iRoot SP单尖充填,比较2组的充... 目的探究并比较iRoot SP单尖充填、AH Plus热牙胶充填技术的充填质量、对术后疼痛的影响与整体治疗效果。方法将84例行根管治疗患者随机分对照组与观察组,各42例。对照组采用AH Plus热牙胶充填,观察组采用iRoot SP单尖充填,比较2组的充填质量和时间、术后1周内的疼痛程度、治疗前后的牙周健康状况、治疗有效率。结果观察组的充填用时显著短于对照组(P<0.05);2组充填效率均较高,差异无统计学意义(P>0.05);术后24 h、1周时,观察组的疼痛状况显著优于对照组(P<0.05);2组内牙髓炎和根尖周炎患者在术中及术后1周时的疼痛状况比较无统计学意义(P>0.05);2组治疗后牙龈指数、菌斑指数、龈沟出血指数均显著降低,且观察组的牙周健康相关指标水平显著低于对照组(P<0.05);2组治疗有效率差异无统计学意义(P>0.05)。结论iRoot SP单尖充填、AH Plus热牙胶充填的充填质量均比较可靠,iRoot SP单尖充填术利于缩短充填用时,有效改善患牙的牙周健康,且术后的舒适性更优。 展开更多
关键词 根管治疗 根管封闭剂 iRoot SP单尖充填 ah Plus热牙胶充填
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CD-AKA-IoV:A Provably Secure Cross-Domain Authentication and Key Agreement Protocol for Internet of Vehicle
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作者 Tsu-Yang Wu Haozhi Wu +2 位作者 Maoxin Tang Saru Kumari Chien-Ming Chen 《Computers, Materials & Continua》 2025年第10期1715-1732,共18页
With the rapid development and widespread adoption of Internet of Things(IoT)technology,the innovative concept of the Internet of Vehicles(IoV)has emerged,ushering in a new era of intelligent transportation.Since vehi... With the rapid development and widespread adoption of Internet of Things(IoT)technology,the innovative concept of the Internet of Vehicles(IoV)has emerged,ushering in a new era of intelligent transportation.Since vehicles are mobile entities,they move across different domains and need to communicate with the Roadside Unit(RSU)in various regions.However,open environments are highly susceptible to becoming targets for attackers,posing significant risks of malicious attacks.Therefore,it is crucial to design a secure authentication protocol to ensure the security of communication between vehicles and RSUs,particularly in scenarios where vehicles cross domains.In this paper,we propose a provably secure cross-domain authentication and key agreement protocol for IoV.Our protocol comprises two authentication phases:intra-domain authentication and cross-domain authentication.To ensure the security of our protocol,we conducted rigorous analyses based on the ROR(Real-or-Random)model and Scyther.Finally,we show in-depth comparisons of our protocol with existing ones from both security and performance perspectives,fully demonstrating its security and efficiency. 展开更多
关键词 authentication key agreement IoV cross-domain
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Light-Weighted Mutual Authentication and Key Agreement in V2N VANET
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作者 Yanan Liu Lei Cao +3 位作者 Zheng Zhang Ge Li Shuo Qiu Suhao Wang 《Computers, Materials & Continua》 2025年第9期4997-5019,共23页
As the adoption of Vehicular Ad-hoc Networks(VANETs)grows,ensuring secure communication between smart vehicles and remote application servers(APPs)has become a critical challenge.While existing solutions focus on vari... As the adoption of Vehicular Ad-hoc Networks(VANETs)grows,ensuring secure communication between smart vehicles and remote application servers(APPs)has become a critical challenge.While existing solutions focus on various aspects of security,gaps remain in addressing both high security requirements and the resource-constrained nature of VANET environments.This paper proposes an extended-Kerberos protocol that integrates Physical Unclonable Function(PUF)for authentication and key agreement,offering a comprehensive solution to the security challenges in VANETs.The protocol facilitates mutual authentication and secure key agreement between vehicles and APPs,ensuring the confidentiality and integrity of vehicle-to-network(V2N)communications and preventing malicious data injection.Notably,by replacing traditional Kerberos password authentication with Challenge-Response Pairs(CRPs)generated by PUF,the protocol significantly reduces the risk of key leakage.The inherent properties of PUF—such as unclonability and unpredictability—make it an ideal defense against physical attacks,including intrusion,semi-intrusion,and side-channel attacks.The results of this study demonstrate that this approach not only enhances security but also optimizes communication efficiency,reduces latency,and improves overall user experience.The analysis proves that our protocol achieves at least 86%improvement in computational efficiency compared to some existed protocols.This is particularly crucial in resource-constrained VANET environments,where it enables efficient data transmission between vehicles and applications,reduces latency,and enhances the overall user experience. 展开更多
关键词 KERBEROS PUF authentication key agreement VANET
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Unleashing the Potential of Metaverse in Social IoV:An Authentication Protocol Based on Blockchain
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作者 Tsu-Yang Wu Haozhi Wu +2 位作者 Maoxin Tang Saru Kumari Chien-Ming Chen 《Computers, Materials & Continua》 2025年第8期3175-3192,共18页
As a model for the next generation of the Internet,the metaverse—a fully immersive,hyper-temporal virtual shared space—is transitioning from imagination to reality.At present,the metaverse has been widely applied in... As a model for the next generation of the Internet,the metaverse—a fully immersive,hyper-temporal virtual shared space—is transitioning from imagination to reality.At present,the metaverse has been widely applied in a variety of fields,including education,social entertainment,Internet of vehicles(IoV),healthcare,and virtual tours.In IoVs,researchers primarily focus on using the metaverse to improve the traffic safety of vehicles,while paying limited attention to passengers’social needs.At the same time,Social Internet ofVehicles(SIoV)introduces the concept of social networks in IoV to provide better resources and services for users.However,the problem of single interaction between SIoVand users has become increasingly prominent.In this paper,we first introduce a SIoVenvironment combined with the metaverse.In this environment,we adopt blockchain as the platform of the metaverse to provide a decentralized environment.Concerning passengers’social data may contain sensitive/private information,we then design an authentication and key agreement protocol calledMSIoV-AKAto protect the communications.Through formal security verifications in the real-or-random(ROR)model and using the AVISPA(Automated Validation of Internet Security Protocols and Applications)tool,we firmly verify the security of the protocol.Finally,detailed comparisons are made between our protocol and robust protocols/schemes in terms of computational cost and communication cost.In addition,we implement the MSIoV-AKA protocol in the Ethereum test network and Hyperledger Sawtooth to show the practicality. 展开更多
关键词 authentication key agreement SIoV metaverse blockchain
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A blockchain-based efficient traceability authentication scheme in VANET
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作者 Junhui Zhao Yingxuan Guo +1 位作者 Longxia Liao Dongming Wang 《Digital Communications and Networks》 2025年第5期1410-1420,共11页
Vehicular Ad-hoc Network(VANET)is a platform that facilitates Vehicle-to-Everything(V2X)interconnection.However,its open communication channels and high-speed mobility introduce security and privacy vulnerabilities.An... Vehicular Ad-hoc Network(VANET)is a platform that facilitates Vehicle-to-Everything(V2X)interconnection.However,its open communication channels and high-speed mobility introduce security and privacy vulnerabilities.Anonymous authentication is crucial in ensuring secure communication and privacy protection in VANET.However,existing anonymous authentication schemes are prone to single points of failure and often overlook the efficient tracking of the true identities of malicious vehicles after pseudonym changes.To address these challenges,we propose an efficient anonymous authentication scheme for blockchain-based VANET.By leveraging blockchain technology,our approach addresses the challenges of single points of failure and high latency,thereby enhancing the service stability and scalability of VANET.The scheme integrates homomorphic encryption and elliptic curve cryptography,allowing vehicles to independently generate new pseudonyms when entering a new domain without third-party assistance.Security analyses and simulation results demonstrate that our scheme achieves effective anonymous authentication in VANET.Moreover,the roadside unit can process 500 messages per 19 ms.As the number of vehicles in the communication domain grows,our scheme exhibits superior messageprocessing capabilities. 展开更多
关键词 VANET Anonymous authentication SECURITY Privacy protection Blockchain
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PLAP-PCPE:Physical-Layer Authentication Protocol Based on PUF and Channel Pre-Equalization for the Internet of Things
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作者 Guo Dengke Gao Yuwei +2 位作者 Cao Kuo Xiong Jun Ma Dongtang 《China Communications》 2025年第3期234-253,共20页
How to ensure the security of device access is a common concern in the Internet of Things(IoT)scenario with extremely high device connection density.To achieve efficient and secure network access for IoT devices with ... How to ensure the security of device access is a common concern in the Internet of Things(IoT)scenario with extremely high device connection density.To achieve efficient and secure network access for IoT devices with constrained resources,this paper proposes a lightweight physical-layer authentication protocol based on Physical Unclonable Function(PUF)and channel pre-equalization.PUF is employed as a secret carrier to provide authentication credentials for devices due to its hardware-based uniqueness and unclonable property.Meanwhile,the short-term reciprocity and spatio-temporal uniqueness of wireless channels are utilized to attach an authentication factor related to the spatio-temporal position of devices and to secure the transmission of authentication messages.The proposed protocol is analyzed formally and informally to prove its correctness and security against typical attacks.Simulation results show its robustness in various radio environments.Moreover,we illustrate the advantages of our protocol in terms of security features and complexity through performance comparison with existing authentication schemes. 展开更多
关键词 IoT physical-layer authentication preequalization PUF wireless channel
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DriveMe:Towards Lightweight and Practical Driver Authentication System Using Single-Sensor Pressure Data
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作者 Mohsen Ali Alawami Dahyun Jung +3 位作者 Yewon Park Yoonseo Ku Gyeonghwan Choi Ki-Woong Park 《Computer Modeling in Engineering & Sciences》 2025年第5期2361-2389,共29页
To date,many previous studies have been proposed for driver authentication;however,these solutions have many shortcomings and are still far from practical for real-world applications.In this paper,we tackle the shortc... To date,many previous studies have been proposed for driver authentication;however,these solutions have many shortcomings and are still far from practical for real-world applications.In this paper,we tackle the shortcomings of the existing solutions and reach toward proposing a lightweight and practical authentication system,dubbed DriveMe,for identifying drivers on cars.Our novelty aspects are 1⃝Lightweight scheme that depends only on a single sensor data(i.e.,pressure readings)attached to the driver’s seat and belt.2⃝Practical evaluation in which one-class authentication models are trained from only the owner users and tested using data collected from both owners and attackers.3⃝Rapid Authentication to quickly identify drivers’identities using a few pressure samples collected within short durations(1,2,3,5,or 10 s).4⃝Realistic experiments where the sensory data is collected from real experiments rather than computer simulation tools.We conducted real experiments and collected about 13,200 samples and 22,800 samples of belt-only and seat-only datasets from all 12 users under different settings.To evaluate system effectiveness,we implemented extensive evaluation scenarios using four one-class detectors One-Class Support Vector Machine(OCSVM),Local Outlier Factor(LOF),Isolation Forest(IF),and Elliptic Envelope(EE),three dataset types(belt-only,seat-only,and fusion),and four different dataset sizes.Our average experimental results show that the system can authenticate the driver with an F1 score of 93.1%for seat-based data using OCSVM classifier,an F1 score of 98.53%for fusion-based data using LOF classifier,an F1 score of 91.65%for fusion-based data using IF classifier,and an F1 score of 95.79%for fusion-based data using EE classifier. 展开更多
关键词 Driver authentication pressure data SENSOR car machine learning
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