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δ-Mapping Algorithm and Its Application in Traffic Flow Problems with Inhomogeneities
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作者 张鹏 刘儒勋 戴世强 《Journal of Shanghai University(English Edition)》 CAS 2003年第4期315-317,共3页
With the Riemann solver to the scalar hyperbolic conservation law with a spatially varying flux, a δ-mapping algorithm was proposed. The algorithm and its prospective application in traffic flow problems were briefed... With the Riemann solver to the scalar hyperbolic conservation law with a spatially varying flux, a δ-mapping algorithm was proposed. The algorithm and its prospective application in traffic flow problems were briefed in the paper. 展开更多
关键词 INHOMOGENEITIES non-strictly hyperbolicity δ-mapping algorithm.
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MR T_(1)-mapping结合动脉自旋标记技术在评估儿童慢性肾脏病肾纤维化和灌注中的应用 被引量:1
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作者 赵佳佳 胡俊 +2 位作者 尹传高 顾东浩 朱晓冬 《临床放射学杂志》 北大核心 2025年第3期513-517,共5页
目的初步研究MR纵向弛豫时间定量成像(T 1-mapping)和动脉自旋标记技术(ASL)在诊断儿童慢性肾脏病(CKD)中的应用价值。方法纳入CKD患儿32例(包括肾脏未萎缩19例,萎缩13例),同期招募健康志愿者30名作对照组,行T 1-mapping和ASL序列扫描,... 目的初步研究MR纵向弛豫时间定量成像(T 1-mapping)和动脉自旋标记技术(ASL)在诊断儿童慢性肾脏病(CKD)中的应用价值。方法纳入CKD患儿32例(包括肾脏未萎缩19例,萎缩13例),同期招募健康志愿者30名作对照组,行T 1-mapping和ASL序列扫描,分别获得肾皮质T 1值和肾皮质血流量(RBF)。比较对照组和CKD组患儿肾皮质T 1值和RBF值的差异,并分析CKD组肾皮质T 1值和RBF值与估算肾小球滤过率(eGFR)、血肌酐(Scr)、血胱抑素C(Cys-C)的相关性。结果CKD组较对照组肾皮质T 1值明显升高、RBF值明显减低(P<0.05);CKD组中,肾脏未萎缩患儿肾皮质T 1值与eGRF、Scr、Cys-C呈高、中度相关(r=-0.832、0.777、0.698,P<0.05),肾脏萎缩患儿肾皮质T 1值与eGRF、Scr呈高度相关(r=0.726、-0.743,P<0.05);CKD组肾皮质RBF与eGRF、Cys-C、Scr呈中度相关(r=0.699、-0.619、-0.554,P<0.05)。结论MR T_(1)-mapping和ASL定量反映肾脏微观病理变化及血流灌注情况,具有预测肾脏慢性病理损伤的潜在价值,有望在肾脏发生不可逆损伤前早期、无创地提供肾脏功能信息。 展开更多
关键词 慢性肾脏病 儿童 T_(1)-mapping 动脉自旋标记 磁共振功能成像
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磁共振T2-mapping成像技术在膝关节骨性关节炎诊断中应用的研究进展
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作者 陈思 《黑龙江医学》 2025年第16期2042-2044,2048,共4页
T2-mapping成像技术通过分析软骨的T2弛豫时间,定量评估软骨组织学结构,揭示软骨中水含量和胶原纤维排列的变化,适用于早期检测软骨损伤和监测疾病进展,对评估软骨健康状况至关重要。T2-mapping成像技术不仅对膝关节骨性关节炎(KOA)的... T2-mapping成像技术通过分析软骨的T2弛豫时间,定量评估软骨组织学结构,揭示软骨中水含量和胶原纤维排列的变化,适用于早期检测软骨损伤和监测疾病进展,对评估软骨健康状况至关重要。T2-mapping成像技术不仅对膝关节骨性关节炎(KOA)的早期诊断和进展监测具有重要价值,还能在软骨修复过程中监测和评估软骨的生化变化。随着成像技术和数据处理能力的进一步发展,T2-mapping成像有望提高诊断精度、优化治疗方案,为KOA的管理和治疗带来革新。文章综述了磁共振成像技术(MRI)中的T2-mapping成像技术在KOA诊断和评估中的应用。 展开更多
关键词 磁共振T2-mapping成像 膝关节 骨性关节炎
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心脏磁共振T_(1)ρ-mapping技术定量评估肥厚型心肌病心肌纤维化及其与心肌应变-左心室重构的关联 被引量:1
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作者 冉玲平 向春林 +2 位作者 唐大中 夏黎明 黄璐 《放射学实践》 北大核心 2025年第11期1356-1362,共7页
目的:采用心脏磁共振T_(1)ρ-mapping技术定量评估肥厚型心肌病(HCM)患者的心肌纤维化,并分析其与心肌应变及左心室(LV)重构的相关性。方法:前瞻性纳入行心脏磁共振检查的40例HCM患者,并纳入15例健康志愿者作对照组,测量LV心肌整体T_(1... 目的:采用心脏磁共振T_(1)ρ-mapping技术定量评估肥厚型心肌病(HCM)患者的心肌纤维化,并分析其与心肌应变及左心室(LV)重构的相关性。方法:前瞻性纳入行心脏磁共振检查的40例HCM患者,并纳入15例健康志愿者作对照组,测量LV心肌整体T_(1)ρ值、最大T_(1)ρ值、初始T_(1)值、LV应变参数(包括纵向、周向、径向应变及应变率)以及LV重构指数(LVRI)。HCM患者按LV有无延迟钆增强(LGE)分为LGE阳性组和LGE阴性组。采用独立样本t检验和单因素方差分析比较组间差异,采用Pearson/Spearman相关分析评估各参数间相关性。结果:HCM组的LVRI(1.3±0.3 vs.0.6±0.1)、LV整体T_(1)ρ值[(46.8±2.2)ms vs.(42.8±1.6)ms]、最大T_(1)ρ值[(51.0±2.8)ms vs.(46.0±1.1)ms]和初始T_(1)值[(1303.0±39.2)ms vs.(1242.5±26.2)ms]均显著高于对照组(P均<0.05),LV心肌应变和应变率均低于对照组(P均<0.05)。LGE阳性组和LGE阴性组的整体T_(1)ρ值、最大T_(1)ρ值、LVRI均显著高于对照组(P均<0.05)。左心室整体T_(1)ρ值、最大T_(1)ρ值、初始T_(1)值与心肌应变和应变率、LVRI有一定相关性(P均<0.05)。结论:T_(1)ρ-mapping技术可定量评估HCM心肌纤维化程度,其参数变化与心肌应变受损及左心室重构密切相关,为HCM的早期诊断和病情评估提供了新的影像学依据。 展开更多
关键词 心脏磁共振成像 肥厚型心肌病 T_(1)ρ-mapping 心肌应变 左心室重构
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磁共振联合T2-mapping对电针治疗腰椎间盘突出症中短期疗效评价的价值分析 被引量:2
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作者 朱薇萍 吕莹 +2 位作者 徐婷 戴德纯 屠建春 《上海针灸杂志》 2025年第3期290-295,共6页
目的通过磁共振(magnetic resonance,MR)常规序列联合T2-mapping观察电针治疗腰椎间盘突出症(lumbar disc herniation,LDH)后有效及无效患者,探讨其在电针治疗LDH中短期疗效评价中的价值。方法随机选择经电针治疗后判定为有效和无效的LD... 目的通过磁共振(magnetic resonance,MR)常规序列联合T2-mapping观察电针治疗腰椎间盘突出症(lumbar disc herniation,LDH)后有效及无效患者,探讨其在电针治疗LDH中短期疗效评价中的价值。方法随机选择经电针治疗后判定为有效和无效的LDH患者各32例,分别设为A组和B组。两组治疗前后分别记录腰椎日本骨科协会(Japanese Orthopaedic Association,JOA)评估治疗分数、Oswestry功能障碍指数(Oswestry disability index,ODI)评分,进行腰椎MR扫描并测量突出椎间盘髓核T2值和突出部分面积。两组均对治疗后JOA改善率及治疗前T2值、突出面积进行相关性分析,并比较治疗后及随访时T2值和突出面积。结果A组治疗前、治疗后及随访时突出椎间盘髓核T2值均明显高于B组(P<0.05);A组治疗1个疗程后突出部分面积明显小于B组(P<0.05)。A组治疗后JOA评分改善率与治疗前突出椎间盘髓核T2值具有中度相关关系(P<0.05),与突出部分面积未见有线性相关关系(P>0.05)。结论通过MR常规序列联合T2-mapping观察突出椎间盘髓核T2值,在电针治疗LDH中短期疗效评价中存在一定的临床价值,其或可为成为LDH保守治疗方案选择的辅助指标之一。 展开更多
关键词 针刺疗法 腰椎间盘突出症 电针 T2-mapping T2值
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磁共振T1-mapping技术定量评价T2DM患者肾功能的价值
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作者 谭源满 梁俊生 +6 位作者 魏清兰 陶娟 董永德 杨概 汪时雨 李扬彬 李小景 《江苏医药》 2025年第3期238-241,共4页
目的探讨磁共振T1-mapping技术定量评价2型糖尿病(T2DM)患者肾功能的价值。方法收集36例T2DM患者资料,依据尿白蛋白/肌酐比值分为单纯T2DM组(A组,18例)和T2DM合并糖尿病肾脏病组(B组,18例)。分析两组相关资料,比较磁共振T1-mapping扫描... 目的探讨磁共振T1-mapping技术定量评价2型糖尿病(T2DM)患者肾功能的价值。方法收集36例T2DM患者资料,依据尿白蛋白/肌酐比值分为单纯T2DM组(A组,18例)和T2DM合并糖尿病肾脏病组(B组,18例)。分析两组相关资料,比较磁共振T1-mapping扫描测量两侧肾皮质T1值。结果B组两侧肾皮质T1值均高于A组同侧肾皮质T1值(P<0.05)。B组两侧肾皮质T1值均与估算的肾小球滤过率呈负相关(P<0.05),左侧肾皮质T1值与BMI呈负相关(P<0.05),右侧肾皮质T1值与胱抑素C、血清肌酐和尿β2微球蛋白呈正相关(P<0.05)。结论磁共振T1-mapping技术对T2DM患者肾脏定量评价具有可行性,T1值可间接预测单侧肾功能变化。 展开更多
关键词 糖尿病 肾脏 磁共振 T1-mapping技术
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基孔肯雅病毒感染相关关节损伤的磁共振表现特征与疼痛程度相关性及T2-Mapping值对损伤严重程度和预后的评估价值
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作者 孙井松 黄孝增 +5 位作者 钱裕东 刘子蔚 邓翠爱 温蕊屏 廖秀娟 何藻鹏 《中国感染控制杂志》 北大核心 2025年第11期1563-1571,共9页
目的 探讨基孔肯雅病毒(CHIKV)关节损伤的磁共振(MR)表现特征及其与疼痛程度的相关性,并分析T2-Mapping值对该类损伤严重程度及预后的评估价值。方法 采用多中心回顾性研究设计,纳入CHIKV感染伴关节疼痛患者,行多关节MR扫描,评估关节积... 目的 探讨基孔肯雅病毒(CHIKV)关节损伤的磁共振(MR)表现特征及其与疼痛程度的相关性,并分析T2-Mapping值对该类损伤严重程度及预后的评估价值。方法 采用多中心回顾性研究设计,纳入CHIKV感染伴关节疼痛患者,行多关节MR扫描,评估关节积液、滑膜增厚、骨髓水肿、软骨损伤等表现,并测定T2-Mapping值。采用视觉模拟量表(VAS)评估疼痛程度,由两名放射科医生独立评估影像表现。结果 共纳入131例患者,关节腔和/或滑液囊积液发生率最高(77.1%,101例),其中膝、踝关节积液占比81.2%(重度17例、轻中度65例),其余关节积液均为轻度。滑膜增厚78例(重度14例、轻中度64例);腱鞘炎27例;骨髓水肿21例(以膝、踝关节为主);关节软骨损伤19例;肌肉软组织水肿114例(重度17例、轻中度97例),踝部Kager脂肪垫水肿28例。T2-Mapping值升高者慢性骨关节痛表现更明显,其中软骨损伤区域T2-Mapping值较正常软骨区域升高40%~60%(共19例),重度损伤软组织的T2-Mapping值为(52.3±6.7) ms,轻中度损伤软组织的T2-Mapping值为(42.3±5.2) ms,二者均高于正常参考值(<35 ms,均P<0.05)。在17例重度软组织损伤患者中,12例存在超过1个月的持续性疼痛,其T2-Mapping值与轻中度损伤患者的T2值比较,差异具有统计学意义(P<0.05),进一步提示T2-Mapping值升高程度与疼痛持续时间及损伤严重程度密切相关。1个月后随访,103例患者疼痛缓解,28例仍疼痛患者中,17例发展为亚急性骨关节痛。骨髓水肿(81.1%)、软骨T2-Mapping值升高(89.5%)、重度滑膜增厚(71.4%)为亚急性骨关节痛“高危MR表现”。关节腔/囊积液、腱鞘炎亚急性化发生率分别为3.0%、7.4%。结论 MR可清晰显示CHIKV关节损伤的炎症及结构性改变,T2-Mapping值可作为评估损伤严重程度和预后的潜在影像学计量参数。 展开更多
关键词 基孔肯雅热 亚急性骨关节痛 MR T2-mapping
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T2-mapping成像技术对膝关节髌软骨损伤分级诊断价值研究
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作者 钟治晖 查婧 +4 位作者 范华刚 黎蕾 王柳仙 郑珍 谢安明 《中国CT和MRI杂志》 2025年第7期173-176,共4页
目的 探讨T2-mapping成像技术对膝关节髌软骨损伤分级诊断价值研究。方法 选取我院2022年2月至2024年2月收治的膝关节髌软骨损伤患者147例作为损伤组,以关节镜结果作为“金标准”,另将45名健康志愿者作为对照组。根据膝关节髌软骨损伤... 目的 探讨T2-mapping成像技术对膝关节髌软骨损伤分级诊断价值研究。方法 选取我院2022年2月至2024年2月收治的膝关节髌软骨损伤患者147例作为损伤组,以关节镜结果作为“金标准”,另将45名健康志愿者作为对照组。根据膝关节髌软骨损伤分级将147例膝关节髌软骨损伤患者分为轻度髌软骨损伤组(Ⅰ、Ⅱ级)102例和重度髌软骨损伤组(Ⅲ、Ⅳ级)45名。收集一般资料、均行膝关节MRI常规扫描及T2-mapping序列扫描,分别比较不同区域软骨T2值,通过SPSS 27.0统计软件进行数据统计分析。构建广义线性混合模型分析T2值与膝关节髌软骨损伤分级之间的关系。RCS分析T2值与患者严重损伤风险的剂量-反应关系。结果 T2-mapping序列诊断膝关节髌软骨损伤分级的准确度为89.18%(239/268)、灵敏度为90.34%(159/176)及特异度为86.96%。5组在股骨内侧髁、股骨外侧髁、内侧胫骨平台、外侧胫骨平台、髌骨关节面的T2值比较差异有统计学意义(P<0.05);其中Ⅳ级组的T2值最高、其次是Ⅲ级组,再次是Ⅱ级组,均高于Ⅰ级组和对照组(P<0.05)。损伤组股骨内侧髁、股骨外侧髁、内侧胫骨平台、外侧胫骨平台的浅层软骨T2值高于深层软骨,比较差异有统计学意义(P<0.05)。损伤组股骨内侧髁和股骨外侧髁的负重区T2值高于非负重区,比较差异有统计学意义(P<0.05)。拟合广义线性混合效应模型分析结果表明,T2值与膝关节髌软骨损伤分级仍存在统计学关联(P<0.001)。Logistic回归模型结合RCS分析显示,T2值与严重损伤风险之间存在非线性剂量-反应关系,随着T2值的增加,严重损伤风险逐渐上升。结论 T2-mapping序列在膝关节髌软骨损伤诊断中准确度高,且T2值与损伤程度和损伤风险密切相关。 展开更多
关键词 T2-mapping 成像技术 膝关节 髌软骨 损伤分级 诊断价值
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An Eulerian-Lagrangian parallel algorithm for simulation of particle-laden turbulent flows 被引量:1
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作者 Harshal P.Mahamure Deekshith I.Poojary +1 位作者 Vagesh D.Narasimhamurthy Lihao Zhao 《Acta Mechanica Sinica》 2026年第1期15-34,共20页
This paper presents an Eulerian-Lagrangian algorithm for direct numerical simulation(DNS)of particle-laden flows.The algorithm is applicable to perform simulations of dilute suspensions of small inertial particles in ... This paper presents an Eulerian-Lagrangian algorithm for direct numerical simulation(DNS)of particle-laden flows.The algorithm is applicable to perform simulations of dilute suspensions of small inertial particles in turbulent carrier flow.The Eulerian framework numerically resolves turbulent carrier flow using a parallelized,finite-volume DNS solver on a staggered Cartesian grid.Particles are tracked using a point-particle method utilizing a Lagrangian particle tracking(LPT)algorithm.The proposed Eulerian-Lagrangian algorithm is validated using an inertial particle-laden turbulent channel flow for different Stokes number cases.The particle concentration profiles and higher-order statistics of the carrier and dispersed phases agree well with the benchmark results.We investigated the effect of fluid velocity interpolation and numerical integration schemes of particle tracking algorithms on particle dispersion statistics.The suitability of fluid velocity interpolation schemes for predicting the particle dispersion statistics is discussed in the framework of the particle tracking algorithm coupled to the finite-volume solver.In addition,we present parallelization strategies implemented in the algorithm and evaluate their parallel performance. 展开更多
关键词 DNS Eulerian-Lagrangian Particle tracking algorithm Point-particle Parallel software
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椎间盘MRI T_(2)-mapping在纤维环撕裂型盘源性下腰痛患者中的应用效果
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作者 梁思武 林莹 +1 位作者 许毅 覃明 《影像研究与医学应用》 2025年第23期56-58,共3页
目的:分析椎间盘MRI T_(2)-mapping在纤维环撕裂型盘源性下腰痛患者中的应用效果。方法:选取2022年1月—2025年3月中国人民解放军联勤保障部队第九二三医院收治的40例盘源性下腰痛(纤维环撕裂型)患者作为纤维环撕裂组,选择同期的40名健... 目的:分析椎间盘MRI T_(2)-mapping在纤维环撕裂型盘源性下腰痛患者中的应用效果。方法:选取2022年1月—2025年3月中国人民解放军联勤保障部队第九二三医院收治的40例盘源性下腰痛(纤维环撕裂型)患者作为纤维环撕裂组,选择同期的40名健康体检者作为健康对照组。均采用MRI扫描,包括常规序列及T_(2)-mapping成像,并进行形态学分析(椎间盘突出程度、椎管狭窄、终板Modic改变等)、T_(2)-mapping定量测量[包括腰椎间盘高信号区(HIZ)面积、椎间盘面积、HIZ面积比例及HIZ相对信号强度],分析疼痛程度[视觉模拟疼痛评分法(VAS)]与影像学参数的相关性。结果:纤维环撕裂组HIZ区域与终板下骨T_(2)值、HIZ面积比例和HIZ相对信号强度均高于健康对照组(P<0.05)。纤维环撕裂组椎间盘突出程度Ⅲ~Ⅳ度、终板Modic改变、椎管狭窄的占比均高于健康对照组(P<0.05)。纤维环撕裂组中,HIZ面积比例与VAS评分呈正相关(r=0.620,P<0.05)。结论:MRI T_(2)-mapping在纤维环撕裂型盘源性下腰痛诊断中有较高的应用价值,HIZ参数与疼痛程度显著相关,可作为临床疼痛评估的潜在影像标志物,为其精准分型及个体化治疗提供了重要依据。 展开更多
关键词 盘源性下腰痛 椎间盘 磁共振成像T_(2)-mapping 纤维环撕裂 终板损伤
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DWI联合T2-mapping技术在布氏杆菌性脊柱炎早期诊断中的价值分析
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作者 魁彩霞 马恩潭 +4 位作者 赵国胜 李德娟 马玉梅 张军福 张学明 《甘肃医药》 2025年第12期1095-1098,共4页
目的:探讨布氏杆菌性脊柱炎(BS)各分期MRI影像特征,重点分析弥散加权成像(DWI)联合T2-mapping技术在布氏杆菌性脊柱炎早期诊断与活动性评估中的临床价值。方法:回顾性分析我院收治并确诊的63例BS患者的MRI资料,根据鲁德涅夫分期法将患... 目的:探讨布氏杆菌性脊柱炎(BS)各分期MRI影像特征,重点分析弥散加权成像(DWI)联合T2-mapping技术在布氏杆菌性脊柱炎早期诊断与活动性评估中的临床价值。方法:回顾性分析我院收治并确诊的63例BS患者的MRI资料,根据鲁德涅夫分期法将患者分为3期:急性期者21例、亚急性期者23例、慢性期者19例,均接受常规MRI+DWI+T2-mapping检查,进行统计学分析。结果:BS急性期病变椎体呈长T1、长T2信号,椎旁软组织肿胀;亚急性期呈不均匀长T1、混杂T2信号,部分可见典型的“许莫氏结节”及椎旁脓肿;慢性期呈混杂信号,椎体前缘可见“鹦鹉嘴”样骨赘。急性期病变椎体ADC值和T2-mapping值高于邻近正常椎体,二者联合诊断敏感度达96.3%。结论:DWI与T2-mapping技术可显著提升BS的早期诊断准确性及敏感性,结合常规MRI能辅助临床实现疾病早期精确诊断。 展开更多
关键词 布氏杆菌性脊柱炎 磁共振成像 弥散加权成像 T2-mapping技术
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PID Steering Control Method of Agricultural Robot Based on Fusion of Particle Swarm Optimization and Genetic Algorithm
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作者 ZHAO Longlian ZHANG Jiachuang +2 位作者 LI Mei DONG Zhicheng LI Junhui 《农业机械学报》 北大核心 2026年第1期358-367,共10页
Aiming to solve the steering instability and hysteresis of agricultural robots in the process of movement,a fusion PID control method of particle swarm optimization(PSO)and genetic algorithm(GA)was proposed.The fusion... Aiming to solve the steering instability and hysteresis of agricultural robots in the process of movement,a fusion PID control method of particle swarm optimization(PSO)and genetic algorithm(GA)was proposed.The fusion algorithm took advantage of the fast optimization ability of PSO to optimize the population screening link of GA.The Simulink simulation results showed that the convergence of the fitness function of the fusion algorithm was accelerated,the system response adjustment time was reduced,and the overshoot was almost zero.Then the algorithm was applied to the steering test of agricultural robot in various scenes.After modeling the steering system of agricultural robot,the steering test results in the unloaded suspended state showed that the PID control based on fusion algorithm reduced the rise time,response adjustment time and overshoot of the system,and improved the response speed and stability of the system,compared with the artificial trial and error PID control and the PID control based on GA.The actual road steering test results showed that the PID control response rise time based on the fusion algorithm was the shortest,about 4.43 s.When the target pulse number was set to 100,the actual mean value in the steady-state regulation stage was about 102.9,which was the closest to the target value among the three control methods,and the overshoot was reduced at the same time.The steering test results under various scene states showed that the PID control based on the proposed fusion algorithm had good anti-interference ability,it can adapt to the changes of environment and load and improve the performance of the control system.It was effective in the steering control of agricultural robot.This method can provide a reference for the precise steering control of other robots. 展开更多
关键词 agricultural robot steering PID control particle swarm optimization algorithm genetic algorithm
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Optimization of Truss Structures Using Nature-Inspired Algorithms with Frequency and Stress Constraints
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作者 Sanjog Chhetri Sapkota Liborio Cavaleri +3 位作者 Ajaya Khatri Siddhi Pandey Satish Paudel Panagiotis G.Asteris 《Computer Modeling in Engineering & Sciences》 2026年第1期436-464,共29页
Optimization is the key to obtaining efficient utilization of resources in structural design.Due to the complex nature of truss systems,this study presents a method based on metaheuristic modelling that minimises stru... Optimization is the key to obtaining efficient utilization of resources in structural design.Due to the complex nature of truss systems,this study presents a method based on metaheuristic modelling that minimises structural weight under stress and frequency constraints.Two new algorithms,the Red Kite Optimization Algorithm(ROA)and Secretary Bird Optimization Algorithm(SBOA),are utilized on five benchmark trusses with 10,18,37,72,and 200-bar trusses.Both algorithms are evaluated against benchmarks in the literature.The results indicate that SBOA always reaches a lighter optimal.Designs with reducing structural weight ranging from 0.02%to 0.15%compared to ROA,and up to 6%–8%as compared to conventional algorithms.In addition,SBOA can achieve 15%–20%faster convergence speed and 10%–18%reduction in computational time with a smaller standard deviation over independent runs,which demonstrates its robustness and reliability.It is indicated that the adaptive exploration mechanism of SBOA,especially its Levy flight–based search strategy,can obviously improve optimization performance for low-and high-dimensional trusses.The research has implications in the context of promoting bio-inspired optimization techniques by demonstrating the viability of SBOA,a reliable model for large-scale structural design that provides significant enhancements in performance and convergence behavior. 展开更多
关键词 OPTIMIZATION truss structures nature-inspired algorithms meta-heuristic algorithms red kite opti-mization algorithm secretary bird optimization algorithm
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RRT^(*)-GSQ:A hybrid sampling path planning algorithm for complex orchard scenarios
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作者 ZHU Qingzhen ZHAO Jiamuyang +1 位作者 DAI Xu YU Yang 《农业工程学报》 北大核心 2026年第3期13-25,共13页
Traditional sampling-based path planning algorithms,such as the rapidly-exploring random tree star(RRT^(*)),encounter critical limitations in unstructured orchard environments,including low sampling efficiency in narr... Traditional sampling-based path planning algorithms,such as the rapidly-exploring random tree star(RRT^(*)),encounter critical limitations in unstructured orchard environments,including low sampling efficiency in narrow passages,slow convergence,and high computational costs.To address these challenges,this paper proposes a novel hybrid global path planning algorithm integrating Gaussian sampling and quadtree optimization(RRT^(*)-GSQ).This methodology aims to enhance path planning by synergistically combining a Gaussian mixture sampling strategy to improve node generation in critical regions,an adaptive step-size and direction optimization mechanism for enhanced obstacle avoidance,a Quadtree-AABB collision detection framework to lower computational complexity,and a dynamic iteration control strategy for more efficient convergence.In obstacle-free and obstructed scenarios,compared with the conventional RRT^(*),the proposed algorithm reduced the number of node evaluations by 67.57%and 62.72%,and decreased the search time by 79.72%and 78.52%,respectively.In path tracking tests,the proposed algorithm achieved substantial reductions in RMSE of the final path compared to the conventional RRT^(*).Specifically,the lateral RMSE was reduced by 41.5%in obstacle-free environments and 59.3%in obstructed environments,while the longitudinal RMSE was reduced by 57.2%and 58.5%,respectively.Furthermore,the maximum absolute errors in both lateral and longitudinal directions were constrained within 0.75 m.Field validation experiments in an operational orchard confirmed the algorithm's practical effectiveness,showing reductions in the mean tracking error of 47.6%(obstacle-free)and 58.3%(with obstructed),alongside a 5.1%and 7.2%shortening of the path length compared to the baseline method.The proposed algorithm effectively enhances path planning efficiency and navigation accuracy for robots,presenting a superior solution for high-precision autonomous navigation of agricultural robots in orchard environments and holding significant value for engineering applications. 展开更多
关键词 ROBOT path planning ORCHARD improved RRT^(*)algorithm Gaussian sampling autonomous navigation
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TWO PARALLEL ALGORITHMS FOR A CLASS OF SPLIT COMMON SOLUTION PROBLEMS
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作者 Truong Minh TUYEN Nguyen Thi TRANG Tran Thi HUONG 《Acta Mathematica Scientia》 2026年第1期505-518,共14页
We study the split common solution problem with multiple output sets for monotone operator equations in Hilbert spaces.To solve this problem,we propose two new parallel algorithms.We establish a weak convergence theor... We study the split common solution problem with multiple output sets for monotone operator equations in Hilbert spaces.To solve this problem,we propose two new parallel algorithms.We establish a weak convergence theorem for the first and a strong convergence theorem for the second. 展开更多
关键词 iterative algorithm Hilbert space metric projection proximal point algorithm
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Gekko Japonicus Algorithm:A Novel Nature-inspired Algorithm for Engineering Problems and Path Planning
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作者 Ke Zhang Hongyang Zhao +2 位作者 Xingdong Li Chengjin Fu Jing Jin 《Journal of Bionic Engineering》 2026年第1期431-471,共41页
This paper introduces a novel nature-inspired metaheuristic algorithm called the Gekko japonicus algorithm.The algo-rithm draws inspiration mainly from the predation strategies and survival behaviors of the Gekko japo... This paper introduces a novel nature-inspired metaheuristic algorithm called the Gekko japonicus algorithm.The algo-rithm draws inspiration mainly from the predation strategies and survival behaviors of the Gekko japonicus.The math-ematical model is developed by simulating various biological behaviors of the Gekko japonicus,such as hybrid loco-motion patterns,directional olfactory guidance,implicit group advantage tendencies,and the tail autotomy mechanism.By integrating multi-stage mutual constraints and dynamically adjusting parameters,GJA maintains an optimal balance between global exploration and local exploitation,thereby effectively solving complex optimization problems.To assess the performance of GJA,comparative analyses were performed against fourteen state-of-the-art metaheuristic algorithms using the CEC2017 and CEC2022 benchmark test sets.Additionally,a Friedman test was performed on the experimen-tal results to assess the statistical significance of differences between various algorithms.And GJA was evaluated using multiple qualitative indicators,further confirming its superiority in exploration and exploitation.Finally,GJA was utilized to solve four engineering optimization problems and further implemented in robotic path planning to verify its practical applicability.Experimental results indicate that,compared to other high-performance algorithms,GJA demonstrates excep-tional performance as a powerful optimization algorithm in complex optimization problems.We make the code publicly available at:https://github.com/zhy1109/Gekko-japonicusalgorithm. 展开更多
关键词 Gekko japonicus algorithm Metaheuristic algorithm Exploration and exploitation Engineering optimization Path planning
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A Quantum-Inspired Algorithm for Clustering and Intrusion Detection
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作者 Gang Xu Lefeng Wang +5 位作者 Yuwei Huang Yong Lu Xin Liu Weijie Tan Zongpeng Li Xiu-Bo Chen 《Computers, Materials & Continua》 2026年第4期1180-1215,共36页
The Intrusion Detection System(IDS)is a security mechanism developed to observe network traffic and recognize suspicious or malicious activities.Clustering algorithms are often incorporated into IDS;however,convention... The Intrusion Detection System(IDS)is a security mechanism developed to observe network traffic and recognize suspicious or malicious activities.Clustering algorithms are often incorporated into IDS;however,conventional clustering-based methods face notable drawbacks,including poor scalability in handling high-dimensional datasets and a strong dependence of outcomes on initial conditions.To overcome the performance limitations of existing methods,this study proposes a novel quantum-inspired clustering algorithm that relies on a similarity coefficient-based quantum genetic algorithm(SC-QGA)and an improved quantum artificial bee colony algorithm hybrid K-means(IQABC-K).First,the SC-QGA algorithmis constructed based on quantum computing and integrates similarity coefficient theory to strengthen genetic diversity and feature extraction capabilities.For the subsequent clustering phase,the process based on the IQABC-K algorithm is enhanced with the core improvement of adaptive rotation gate and movement exploitation strategies to balance the exploration capabilities of global search and the exploitation capabilities of local search.Simultaneously,the acceleration of convergence toward the global optimum and a reduction in computational complexity are facilitated by means of the global optimum bootstrap strategy and a linear population reduction strategy.Through experimental evaluation with multiple algorithms and diverse performance metrics,the proposed algorithm confirms reliable accuracy on three datasets:KDD CUP99,NSL_KDD,and UNSW_NB15,achieving accuracy of 98.57%,98.81%,and 98.32%,respectively.These results affirm its potential as an effective solution for practical clustering applications. 展开更多
关键词 Intrusion detection CLUSTERING quantum artificial bee colony algorithm K-MEANS quantum genetic algorithm
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Information Diffusion Models and Fuzzing Algorithms for a Privacy-Aware Data Transmission Scheduling in 6G Heterogeneous ad hoc Networks
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作者 Borja Bordel Sánchez Ramón Alcarria Tomás Robles 《Computer Modeling in Engineering & Sciences》 2026年第2期1214-1234,共21页
In this paper,we propose a new privacy-aware transmission scheduling algorithm for 6G ad hoc networks.This system enables end nodes to select the optimum time and scheme to transmit private data safely.In 6G dynamic h... In this paper,we propose a new privacy-aware transmission scheduling algorithm for 6G ad hoc networks.This system enables end nodes to select the optimum time and scheme to transmit private data safely.In 6G dynamic heterogeneous infrastructures,unstable links and non-uniform hardware capabilities create critical issues regarding security and privacy.Traditional protocols are often too computationally heavy to allow 6G services to achieve their expected Quality-of-Service(QoS).As the transport network is built of ad hoc nodes,there is no guarantee about their trustworthiness or behavior,and transversal functionalities are delegated to the extreme nodes.However,while security can be guaranteed in extreme-to-extreme solutions,privacy cannot,as all intermediate nodes still have to handle the data packets they are transporting.Besides,traditional schemes for private anonymous ad hoc communications are vulnerable against modern intelligent attacks based on learning models.The proposed scheme fulfills this gap.Findings show the probability of a successful intelligent attack reduces by up to 65%compared to ad hoc networks with no privacy protection strategy when used the proposed technology.While congestion probability can remain below 0.001%,as required in 6G services. 展开更多
关键词 6G networks ad hoc networks PRIVACY scheduling algorithms diffusion models fuzzing algorithms
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Integrated diagnosis of abnormal energy consumption in converter steelmaking using GWO-SVM-K-means algorithms
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作者 Fei-Xiang Dai Xiang-Jun Bao +2 位作者 Lu Zhang Xiao-Jing Yang Guang Chen 《Journal of Iron and Steel Research International》 2026年第1期458-468,共11页
To address the issue of abnormal energy consumption fluctuations in the converter steelmaking process,an integrated diagnostic method combining the gray wolf optimization(GWO)algorithm,support vector machine(SVM),and ... To address the issue of abnormal energy consumption fluctuations in the converter steelmaking process,an integrated diagnostic method combining the gray wolf optimization(GWO)algorithm,support vector machine(SVM),and K-means clustering was proposed.Eight input parameters—derived from molten iron conditions and external factors—were selected as feature variables.A GWO-SVM model was developed to accurately predict the energy consumption of individual heats.Based on the prediction results,the mean absolute percentage error and maximum relative error of the test set were employed as criteria to identify heats with abnormal energy usage.For these heats,the K-means clustering algorithm was used to determine benchmark values of influencing factors from similar steel grades,enabling root-cause diagnosis of excessive energy consumption.The proposed method was applied to real production data from a converter in a steel plant.The analysis reveals that heat sample No.44 exhibits abnormal energy consumption,due to gas recovery being 1430.28 kg of standard coal below the benchmark level.A secondary contributing factor is a steam recovery shortfall of 237.99 kg of standard coal.This integrated approach offers a scientifically grounded tool for energy management in converter operations and provides valuable guidance for optimizing process parameters and enhancing energy efficiency. 展开更多
关键词 Converter smelting process Abnormal energy diagnosis Gray wolf optimization algorithm Support vector machine K-means clustering algorithm
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