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ISOPERIMETRIC INEQUALITIES FOR INTEGRAL GEOMETRIC INVARIANTS OF RANDOM LINES
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作者 Gaoyong ZHANG 《Acta Mathematica Scientia》 2025年第1期189-199,共11页
Isoperimetric type inequalities for integral geometric invariants of random lines in the Euclidean space are shown.Entropy inequalities of probability densities on the affine Grassmann manifold of lines are given.
关键词 isoperimetric inequality convex body random points random lines chord integral Riesz potential ENTROPY
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Some Random Coincidence Point and Common Fixed Point Results in Cone Metric Spaces Over Banach Algebras
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作者 JIANG Bing-hua CAI Ze-lin CHEN Jin-yang 《Chinese Quarterly Journal of Mathematics》 2019年第4期362-381,共20页
In this paper,we obtain some tripled common random fixed point and tripled random fixed point theorems with several generalized Lipschitz constants in such spaces.We consider the obtained assertions without the assump... In this paper,we obtain some tripled common random fixed point and tripled random fixed point theorems with several generalized Lipschitz constants in such spaces.We consider the obtained assertions without the assumption of normality of cones.The presented results generalize some coupled common fixed point theorems in the existing literature. 展开更多
关键词 Tripled random fixed point Tripled random coincidence point Cone metric space over Banach algebra Generalized Lipschitz constant Tripled common random fixed point
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Pestle needling at Yāoyángguān-Bāzhèn points for intractable lumbodynia after lumbar disc herniation surgery: A randomized controlled trial 被引量:1
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作者 Junfeng ZHANG Yaochi WU +1 位作者 Shisheng LI Yijun SUN 《World Journal of Acupuncture-Moxibustion》 CSCD 2019年第3期194-199,共6页
Objective:To observe the differences of clinical efficacy of intractable lumbodynia after lumbar disc herniation surgery treated by pestle needling at Yāoyángguān Bāzhèn points,electroacupuncture and west... Objective:To observe the differences of clinical efficacy of intractable lumbodynia after lumbar disc herniation surgery treated by pestle needling at Yāoyángguān Bāzhèn points,electroacupuncture and western medication.Methods:A total of 210 patients with intractable lumbodynia after lumbar disc herniation were randomly divided into pestle needle group,electroacupuncture group and western medication group,with 70 cases in each group.The pestle needle group was treated with pestle needle poking Yāoyángguān-Bāzhèn(GV3-Bāzhèn)points.The electroacupuncture group was treated with conventional electroacupuncture,and the western medication group was treated with oral diclofenac sodium dual release enteric-coated capsules(Difene).The pestle needle group and the electroacupuncture group were treated once a day,and there was 1 day of rest after 6 days of treatment,and a course of treatment included 7 days,and a total of 3 courses of treatment were performed.The western medication group took 1 Difene capsule(75 mg)at a time,with once a day continuing for 21 days.Visual Analog Scale(VAS),Pain Rating Index(PRI)and Present Pain Intensity(PPI)were used to observe the improvement of pain before and after treatment,and the waist muscle tone was examined and the clinical efficacy was observed.Results:The post-treatment VAS,PRI,and PPI scores of the three groups were all lower than pretreatment,and the differences were statistically significant(all P<0.05).There were no statistically significant differences in VAS,PRI and PPI scores between pestle needle group and western medication group(all P>0.05).Meanwhile,they were all lower than the electroacupuncture group,and the differences were statistically significant(both P<0.05).After treatment,the waist muscle tone of the three groups was higher than that pre-treatment,and the differences were statistically significant(all P<0.05).After treatment,the waist muscle tone of the pestle needle group was higher than the electroacupuncture group,and the electroacupuncture group was higher than the western medication group,and the differences were statistically significant(both P<0.05).The total effective rate was 88.57%in the pestle needle group,80%in the electroacupuncture group,and 77.14%in the western medication group,and there were no statistically significant differences among the groups(P>0.05).Conclusions:Pestle needle poking GV3-Bāzhèn points can effectively relieve intractable lumbodynia after lumbar disc herniation surgery,decrease VAS,PRI,PPI scores and relieve waist muscle tone,and the effect was remarkable. 展开更多
关键词 Lumbar disc herniation After surgery Intractable lumbodynia Low backache Pestle needle Bāzhèn points randomized controlled trial(RCT)
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A RANDOM FIXED POINT ITERATION FOR THREE RANDOM OPERATORS ON UNIFORMLY CONVEX BANACH SPACES
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作者 Binayak S.Choudhury 《Analysis in Theory and Applications》 2003年第2期99-107,共9页
In the present paper we introduce a random iteration scheme for three random operators defined on a closed and convex subset of a uniformly convex Banach space and prove its convergence to a common fixed point of thre... In the present paper we introduce a random iteration scheme for three random operators defined on a closed and convex subset of a uniformly convex Banach space and prove its convergence to a common fixed point of three random operators. The result is also an extension of a known theorem in the corresponding non-random case. 展开更多
关键词 random iteration fixed point uniformly convex Banach space
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On a Class of Plane Random Walks with Absorbing Points
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作者 Zhou Chizhong (Computer Department) 《岳阳大学学报》 CAS 1998年第1期11-17,共7页
L. Shapiro has presented and solved a problem of a class of random walks with absorbing points on plane lattice points .[1]He divided the all lattice points on line y=x(x>0) into two classes by modulo 2, and select... L. Shapiro has presented and solved a problem of a class of random walks with absorbing points on plane lattice points .[1]He divided the all lattice points on line y=x(x>0) into two classes by modulo 2, and selected one of the two classes to be the set of absorbing points. In this paper,we generalize the Shapiro problem:divide the all lattice points on line y = x(x>0) into k classes by modulo k,and select one class or more classes of the k classes to be the set of absorbing points. We solve the generalized problem by using the residue method and give an application of it to probability theory. 展开更多
关键词 random WALK absorbing point RESIDUE method.
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Effectiveness of electroacupuncture at Jiaji acupoints(EX-B 2), plus moxibustion and intermediate on postherpetic neuralgia: a randomized controlled trial 被引量:12
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作者 Wang Lei Qiu Ling +6 位作者 Zheng Xu Ou-yang Jian-bing Zhang Min He Liu Zeng Shuai Liu Bo Peng Jinlin 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2020年第1期121-127,共7页
OBJECTIVE:To investigate the effectiveness of electroacupuncture at Jiaji acupoints(EX-B 2)plus moxibustion and intermediate frequency on postherpetic neuralgia(PHN).METHODS:A total of 140 outpatients who satisfied th... OBJECTIVE:To investigate the effectiveness of electroacupuncture at Jiaji acupoints(EX-B 2)plus moxibustion and intermediate frequency on postherpetic neuralgia(PHN).METHODS:A total of 140 outpatients who satisfied the inclusion criteria and volunteered for this treatment were randomly divided into treatment(n=70)and control(n=70)groups.Both groups received a localized lesion area and electroacupuncture treatment combined with moxibustion and intermediate frequency.The treatment group(TG)increased acupuncture at Jiaji acupoints(EX-B 2)and electroacupuncture.Pain and anxiety were assessed before and after 5,10,15,and 20 treatments by using visual pain simulation score(VAS)and Hamilton anxiety scale(HAMA),respectively.Clinical efficacy was also evaluated.RESULTS:The baseline between the two groups did not significantly differ(P>0.05).The VAS and HAMA scores of the two groups after treatment significantly decreased compared with those of various treatment stages(P>0.05).The HAMA score(P<0.01)of TG was lower than that of the control group(CG).The VAS score of TG was lower than that of CG in the 5th and 10th treatments(P<0.01).In the 15 th and 10 th scores,CG was also superior to TG(P<0.05).CONCLUSION:The combined treatment of electroacupuncture at Jiaji acupoints(EX-B 2),moxibustion,and intermediate frequency can relieve the pain and anxiety symptoms of PHN.The efficacy of the combined treatment was superior to traditional acupuncture. 展开更多
关键词 ELECTROACUPUNCTURE point EX-B 2(Jiaji) Neuralgia postherpetic Pain randomized controlled trial
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Effect of scar-producing moxibustion at the acupoints Zusanli(ST 36) and Feishu(BL 13) on neutrophil-to-lymphocyte ratio and quality of life in patients with non-small-cell lung cancer: A randomized,controlled trial 被引量:5
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作者 Zhang Mengxue Guan Ling +1 位作者 Wang Lili Li Ying 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2018年第3期439-446,共8页
OBJECTIVE: To evaluate the effect of heat stimulation via scar-producing moxibustion at the acupoints Zusanli(ST 36) and Feishu(BL 13) on the neutrophil-to-lymphocyte ratio(NLR) and quality of life in patients with no... OBJECTIVE: To evaluate the effect of heat stimulation via scar-producing moxibustion at the acupoints Zusanli(ST 36) and Feishu(BL 13) on the neutrophil-to-lymphocyte ratio(NLR) and quality of life in patients with non-small-cell lung cancer(NSCLC).METHODS: Seventy patients with NSCLC were randomly assigned into two groups: group A received scar-producing moxibustion at the acupoints Zusanli(ST 36) and Feishu(BL 13) every day for 6 weeks, while group B received no intervention(control group). Outcome measures were the NLR and the scores from the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire(EORTC QLQ-C30). The NLR and the EORTC QLQ-C30 were assessed at baseline and at the end of 6 weeks.RESULTS: Five participants dropped out, leaving afinal total of 65 participants who completed the trial. Groups A and B had a similar mean NLR at baseline. After the treatment course, the NLR in group A was significantly lower than that in group B(P <0.001). Compared with group B, the EORTC QLQ-C30 scores in group A were significantly greater in terms of global health status or quality of life(P < 0.001) and function(P < 0.05), and significantly lower in terms of symptoms(P < 0.05).CONCLUSION: The present study suggests that performing scar-producing moxibustion by heat-stimulating the acupoints Zusanli(ST 36) and Feishu(BL13) effectively decreases the NLR and improves the quality of life in patients with NSCLC. 展开更多
关键词 Carcinoma non-small-cell lung Scar-ring MOXIBUSTION point ST36 (Zusanli) point BL13(Feishu) Immunity Neutrophils Lymphocytes Quality of life randomIZED controlled trial
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结合倒置残差模块和可微分RANSAC算法的点云配准模型
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作者 李维乾 葛文豪 陈金广 《计算机与现代化》 2026年第2期1-10,共10页
针对复杂和存在遮挡的点云数据整体和局部特征融合程度低,以及传统鲁棒估计算法无法集成到深度学习训练流程的问题,本文提出一种基于改进PointNet++和随机采样一致算法的点云配准网络模型。首先,使用融合倒置残差模块的PointNet++网络... 针对复杂和存在遮挡的点云数据整体和局部特征融合程度低,以及传统鲁棒估计算法无法集成到深度学习训练流程的问题,本文提出一种基于改进PointNet++和随机采样一致算法的点云配准网络模型。首先,使用融合倒置残差模块的PointNet++网络提取局部点云特征,生成融合全局和局部特征信息的特征描述符;其次,使用局部特征Transformer模块生成暂定的点对应和置信度分数;随后,引入神经采样器以保证RANSAC采样过程的可微分性,并使用可微分的几何求解器计算出点云对之间的刚性变换矩阵;最后,设计可训练质量函数以在每次迭代中优化评估指标,将鲁棒估计算法集成到训练流程中,最终完成点云配准。在3个公开的大规模点云数据集3DMatch、ETH和KITTI上的多次对比实验结果表明,本文方法在3DMatch上的特征匹配召回率达到98.4%,较SpinNet网络提高了0.8百分点;在ETH和KITTI上的特征匹配召回率和正确率分别达到98.5%和99.57%,较SpinNet网络分别提高了5.7百分点和0.5个百分点。在处理多个密度不均匀、存在遮挡的复杂点云数据集时,本文方法的表现优于现有先进方法,能有效提高配准精度。 展开更多
关键词 点云配准 鲁棒估计 特征描述符 pointNet++ 倒置残差 随机采样一致算法
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恢刺肌肉起止点治疗脑卒中后上肢痉挛性瘫痪:随机对照试验
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作者 尚凯 李洪艳 +3 位作者 郭和东 攸泰然 郭航天 顿华帅 《中国针灸》 北大核心 2026年第1期9-15,共7页
目的:观察恢刺肌肉起止点治疗脑卒中后上肢痉挛性瘫痪的临床疗效。方法:将62例脑卒中后上肢痉挛性瘫痪患者随机分为观察组和对照组,每组31例。两组均予基础治疗,观察组予针刺健侧顶颞前斜线、百会、印堂、双侧风池,恢刺选取患侧上肢肱... 目的:观察恢刺肌肉起止点治疗脑卒中后上肢痉挛性瘫痪的临床疗效。方法:将62例脑卒中后上肢痉挛性瘫痪患者随机分为观察组和对照组,每组31例。两组均予基础治疗,观察组予针刺健侧顶颞前斜线、百会、印堂、双侧风池,恢刺选取患侧上肢肱二头肌起止点、尺侧腕屈肌起止点和桡侧腕屈肌起止点;对照组予常规针刺,穴取健侧顶颞前斜线、百会、印堂、水沟、双侧风池和患侧极泉、尺泽等。两组针刺均每日1次,每周5次,连续治疗4周。分别于治疗前后观察两组患者患侧上肢改良Ashworth痉挛评定量表(MAS)评级、Fugl-Meyer上肢运动功能评定(FMA-UE)评分和改良Barthel指数(MBI)评分,并于治疗后评定两组临床疗效。结果:治疗后,两组患者患侧上肢MAS评级均较治疗前降低(P<0.001,P<0.05),患侧FMA-UE、上肢MBI评分均较治疗前升高(P<0.001);观察组患者患侧FMA-UE、上肢MBI评分高于对照组(P<0.01)。观察组临床疗效优于对照组(P<0.05)。结论:恢刺肌肉起止点可有效改善脑卒中后上肢痉挛性瘫痪,降低肌张力,改善运动功能,提高生活质量。 展开更多
关键词 脑卒中 上肢痉挛性瘫痪 针刺 恢刺 肌肉起止点 随机对照试验
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经皮耳穴迷走神经刺激治疗原发性帕金森病:随机对照单盲试验
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作者 余泽程 周志成 +7 位作者 郑春叶 苏巧珍 侯小燕 雒晓东 刘梓言 蓝晓艳 王利军 李哲 《中国针灸》 北大核心 2026年第2期168-175,共8页
目的:观察经皮耳穴迷走神经刺激(taVNS)对原发性帕金森病(PD)自主神经症状和运动症状的治疗效果。方法:将60例原发性PD患者随机分为观察组30例(剔除1例、脱落1例)和对照组30例(剔除4例、脱落1例)。两组患者予口服复方左旋多巴治疗,若入... 目的:观察经皮耳穴迷走神经刺激(taVNS)对原发性帕金森病(PD)自主神经症状和运动症状的治疗效果。方法:将60例原发性PD患者随机分为观察组30例(剔除1例、脱落1例)和对照组30例(剔除4例、脱落1例)。两组患者予口服复方左旋多巴治疗,若入组时已服用复方左旋多巴类以外的抗PD药物,维持入组前用药方案,连续治疗8周。观察组使用SDZ-ⅡB型电子针疗仪对耳甲区(每次取单侧,两耳交替进行)进行taVNS治疗,选择脉冲频率4 Hz/20 Hz疏密波,电流5~10 mA,每次30 min,每周治疗3次,至少隔天进行,共治疗8周。对照组对耳舟区进行脉冲刺激治疗,操作、疗程均同观察组。于治疗前和治疗后,观察两组原发性帕金森病自主神经症状量表(SCOPA-AUT)评分、世界运动障碍协会修订版帕金森病综合评价量表(MDS-UPDRS)-Ⅲ/Ⅱ评分、中医老年颤证功能障碍评分、改良H-Y分级、帕金森患者生活质量调查量表(PDQ-39)评分,并于治疗后进行安全性评价。结果:治疗后,观察组患者SCOPA-AUT、MDS-UPDRS-Ⅲ/Ⅱ、中医老年颤证功能障碍评分和PDQ-39评分均较治疗前降低(P<0.001,P<0.05);对照组PDQ-39评分较治疗前升高(P<0.05),其余指标治疗前后比较差异无统计学意义(P>0.05);两组患者H-Y分级治疗后比较差异无统计学意义(P>0.05)。观察组患者SCOPA-AUT、MDS-UPDRS-Ⅱ、中医老年颤证功能障碍评分和PDQ-39评分降低幅度均大于对照组(P<0.001)。两组未见明显不良反应。结论:taVNS辅助复方左旋多巴治疗可以改善原发性PD患者的自主神经症状和运动症状,提高其日常生活质量,且无不良反应。 展开更多
关键词 原发性帕金森病 经皮耳穴迷走神经刺激 自主神经症状 运动症状 耳穴 随机对照试验
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汽油道路运输罐式车辆停驻点类型识别方法
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作者 周锦婷 袁梦 李帅杰 《公路交通科技》 北大核心 2026年第1期25-32,共8页
【目标】通过对油品运输车辆轨迹停驻点的信息分类和数据处理,以加强其运输途中的安全管控。【方法】本研究基于油品运输车辆轨迹数据,提出了车辆停驻点阈值确定方法,在对停驻点类型标定基础上构建包含停驻点特征、兴趣点特征、停驻类... 【目标】通过对油品运输车辆轨迹停驻点的信息分类和数据处理,以加强其运输途中的安全管控。【方法】本研究基于油品运输车辆轨迹数据,提出了车辆停驻点阈值确定方法,在对停驻点类型标定基础上构建包含停驻点特征、兴趣点特征、停驻类簇特征3个特征子集的停驻行为特征集,分别建立支持向量机模型和随机森林模型,运用网格搜索算法确定最优参数组合,将停驻行为特征集作为自变量,将停驻类型作为因变量,区分车辆归场点、装货点、卸货点和其他点,通过比较4种分类评估指标,对比模型预测性能确定最优分类模型。【结果】包含3个子集的停驻行为特征集能够有效识别停驻点类型;随机森林模型分类性能优于支持向量机模型,分类准确率超过90%;停驻点特征、兴趣点特征、停驻类簇特征3个特征子集中对分类结果影响最大的特征分别是停驻时长、距加油站距离、簇内总计停驻时长;全部特征中对分类结果影响最大的是停驻时长;“是否首末点”与“簇内车辆熵”特征的引入对分类同样有较大贡献。【结论】研究结果可用于确定车辆在途装载状态,分析车辆出行特征,为危险货物运输安全监管提供支持。 展开更多
关键词 智能交通 停驻点类型识别 随机森林模型 轨迹数据 支持向量机模型
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RH精炼炉脱碳氧位的预测控制研究
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作者 王姿涵 张宇鹏 +4 位作者 赵定国 薛月凯 王书桓 李晨晓 周朝刚 《冶金能源》 北大核心 2026年第1期70-75,共6页
为了准确预测RH精炼炉的脱碳氧位,基于某厂生产数据,应用随机森林算法,BP神经网络模型和支持向量回归模型分别划分训练集和测试集,预测了脱碳氧位。结果表明:BP神经网络模型的预测效果比另外两种模型性能更好,在5%以内的范围预测准确率... 为了准确预测RH精炼炉的脱碳氧位,基于某厂生产数据,应用随机森林算法,BP神经网络模型和支持向量回归模型分别划分训练集和测试集,预测了脱碳氧位。结果表明:BP神经网络模型的预测效果比另外两种模型性能更好,在5%以内的范围预测准确率达到85%。随后统计了在不同条件下的氧位分布情况,并通过影响因素的权值对新的样本的冶炼周期、最高真空度、吹氧量、氮气消耗进行调整,基于BP神经网络模型进行了实验验证,最终实现了RH精炼炉脱碳氧位的窄范围控制。 展开更多
关键词 RH精炼 BP神经网络模型 支持向量回归模型 随机森林算法 脱碳氧位
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耳穴压丸联合揿针干预气郁质儿童青少年近视的疗效观察
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作者 薛雨辛 李甜甜 +6 位作者 杨潮 李铁军 武燕 李喜文 陈士君 吴小艳 杨迎新 《中国中医眼科杂志》 2026年第3期225-230,250,共7页
目的观察耳穴压丸联合揿针防治气郁质中低度近视儿童青少年的临床疗效。方法纳入2023年5月1日—2023年12月1日在首都医科大学附属北京中医医院就诊的近视患儿64例(128只眼),随机分为对照组和试验组各32例(64只眼)。最终纳入治疗组30例(6... 目的观察耳穴压丸联合揿针防治气郁质中低度近视儿童青少年的临床疗效。方法纳入2023年5月1日—2023年12月1日在首都医科大学附属北京中医医院就诊的近视患儿64例(128只眼),随机分为对照组和试验组各32例(64只眼)。最终纳入治疗组30例(60只眼),对照组28例(56只眼)。对照组在验光配镜的基础上仅进行健康宣教;治疗组在对照组的基础上,予耳穴压丸和揿针干预。2组均干预6个月,分别于治疗前后观察并比较2组患者的等效球镜(SE)度数、裸眼视力(UCVA)、眼轴及眼轴增长量、调节幅度、气郁质评分,并统计治疗过程中的不良事件发生率。结果(1)SE度数:2组治疗后SE度数均大于治疗前,差异均有统计学意义(Z_(治疗组)=2.700,P=0.007;Z_(对照组)=4.584,P=0.000)。治疗后,2组间SE度数比较,差异无统计学意义(P>0.05),而进展量比较,治疗组低于对照组,差异有统计学意义(Z=2.628,P=0.009)。(2)UCVA:2组最佳裸眼视力治疗前后及治疗后比较,差异均无统计学意义(P>0.05)。(3)眼轴及眼轴增长量:2组治疗后眼轴长度均长于治疗前,差异均有统计学意义(t_(治疗组)=6.420、t_(对照组)=11.138,均P=0.000)。治疗后,2组间眼轴长度比较,差异无统计学意义(P>0.05),而增长率比较,治疗组低于对照组,差异有统计学意义(t=-4.532,P=0.000)。治疗后,(4)调节幅度:治疗组治疗后调节幅度高于治疗前,差异有统计学意义(Z=2.509,P=0.012)。对照组治疗后调节幅度与治疗前比较,差异无统计学意义(P>0.05)。治疗后,2组间调节幅度及进展量比较,差异均无统计学意义(P>0.05)。(5)气郁质评分:治疗组治疗后气郁质评分低于治疗前,差异有统计学意义(t=-5.593,P=0.000);对照组治疗后气郁质评分与治疗前比较,差异无统计学意义(P>0.05)。治疗后,治疗组气郁质评分低于对照组,差异有统计学意义(t=-2.681,P=0.010)。(6)临床疗效:治疗后治疗组有效率为76.67%高于对照组(53.57%),差异有统计学意义(χ^(2)=6.839,P=0.009)。(7)安全性评价:2组患儿治疗期间均未发现明显不良反应事件。结论耳穴压丸联合揿针干预可有效控制中低度近视儿童青少年近视进展,同时可改善偏颇体质,安全性良好,值得临床推广。 展开更多
关键词 中低度近视 耳穴压丸 揿针 儿童青少年 中医体质 临床疗效
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Common Fixed Point Theorems for Sequences of φ-type Contraction Set-valued Mappings 被引量:9
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作者 WU Jian-rong LIU Hai-yan 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期504-510,共7页
In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings a... In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings are also obtained. 展开更多
关键词 sequence of set-valued mappings common fixed point random fixed point metric space
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快速鲁棒掌子面全局节理特征提取算法
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作者 白宇 郝毅仁 +4 位作者 陈玮 裴少康 王贺 王继超 方浩 《科学技术与工程》 北大核心 2026年第3期1157-1165,共9页
隧道掌子面监测对于保障施工安全与工程质量至关重要,然而传统依赖手工测量和现场观察的监测方式效率低下且精度受限。为提升监测水平,提出一种结合深度学习的掌子面快速数字化方法。该方法通过构建掌子面单应变换模型,运用基于深度学... 隧道掌子面监测对于保障施工安全与工程质量至关重要,然而传统依赖手工测量和现场观察的监测方式效率低下且精度受限。为提升监测水平,提出一种结合深度学习的掌子面快速数字化方法。该方法通过构建掌子面单应变换模型,运用基于深度学习的特征匹配算法和基于多尺度信息的快速自适应节理特征提取算法,实现不依赖相机参数和拍摄角度的快速、准确节理特征提取,并借助快速节理检测和融合方法达成实时性监测。实验结果显示,此方法能够有效提取全局掌子面节理信息,显著提高数据采集效率,降低操作难度。综上,该方法为隧道工程监测提供了全新的思路与方法,有力保障了隧道施工安全。 展开更多
关键词 掌子面图像 单应变换 深度学习特征点 节理特征提取 GPU加速 随机样本一致算法
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基于PointNet++进行附属设施语义分割的隧道收敛变形分析 被引量:3
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作者 卞政 石波 +3 位作者 吴凡 王静 赵凯 杨兴宜 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第11期4827-4839,共13页
随着城市轨道交通日趋广泛,隧道结构变形引起的地铁安全事故凸显,亟需对运营期隧道进行变形检测。隧道衬砌作为隧道变形分析的研究对象,衬砌内表面存在的大量附属设施影响隧道收敛变形分析精度。为了提高变形分析精度,解决点云处理环节... 随着城市轨道交通日趋广泛,隧道结构变形引起的地铁安全事故凸显,亟需对运营期隧道进行变形检测。隧道衬砌作为隧道变形分析的研究对象,衬砌内表面存在的大量附属设施影响隧道收敛变形分析精度。为了提高变形分析精度,解决点云处理环节中存在的自动化程度低的问题,提出基于PointNet++点云语义分割的隧道收敛变形分析方法。首先利用深度学习方法进行点云语义分割,对隧道衬砌附属设施进行自动滤除。然后对隧道衬砌进行断面提取,利用随机抽样一致性算法(Random Sample Consensus,RANSAC)对隧道断面点云进行采样,分析隧道收敛变形程度,从Z+F PROFILER 9012A激光断面扫描仪获取山东省山东大学地铁盾构隧道点云实测数据上并进行应用。研究结果表明:所提出的处理方法可以有效地将大规模隧道衬砌与连接紧密的附属设施分离出来,隧道附属设施总体分类精度达到96%,滤波结果较好地保留了隧道衬砌原始形态特征。在对隧道整体和局部收敛变形分析的重复性验证中,测试区间内隧道整体变形精度往返测长半轴平均偏差为1.04 mm,短半轴平均偏差为0.9 mm,测试区间内隧道局部收敛变形往返测标准差最小为0.773 mm,最大为0.938 mm,可以满足隧道收敛变形分析的精度需求。研究结果可以有效提升处理大规模隧道数据的自动化程度,具有良好的有效性与可靠性,对运营期地铁隧道收敛变形检测或监测有较好的实践应用意义。 展开更多
关键词 轨道交通隧道 激光点云 收敛变形分析 点云深度学习 随机抽样一致性
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Spatio-temporal point pattern analysis on Wenchuan strong earthquake 被引量:3
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作者 Peijian Shi Jie Liu Zhen Yang 《Earthquake Science》 CSCD 2009年第3期231-237,共7页
For exploring the aftershock occurrence process of the 2008 Wenchuan strong earthquake, the spatio-temporal point pattern analysis method is employed to study the sequences of aflershocks with magnitude M≥4.0, M≥4.5... For exploring the aftershock occurrence process of the 2008 Wenchuan strong earthquake, the spatio-temporal point pattern analysis method is employed to study the sequences of aflershocks with magnitude M≥4.0, M≥4.5, and M≥5.0. It is found that these data exhibit the spatio-temporal clustering on a certain distance scale and on a certain time scale. In particular, the space-time interaction obviously strengthens when the distance is less than 60 km and the time is less than 260 h for the first two aftershock sequences; however, it becomes strong when the distance scale is less than 80 km and the time scale is less than 150 h for the last aftershock sequence. The completely spatial randomness analysis on the data regardless of time component shows that the spatial clustering of the aftershocks gradually strengthens on the condition that the distance is less than 60 km. The results are valuable for exploring the occurrence rules of the Wenchuan strong earthquake and for predicting the aftershocks. 展开更多
关键词 Wenchuan earthquake completely spatial randomness spatio-temporal point pattern K-FUNCTION
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基于轻量级网络和加权RF的点云分类分割算法
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作者 赵夫群 郝寒竹 余佳乐 《图学学报》 北大核心 2026年第1期143-151,共9页
针对点云分类分割方法中存在的高计算开销、复杂网络模型等问题,提出一种基于轻量级网络和加权随机森林(RF)的点云分类分割算法。该算法采用层次化的方式实现高效分类分割,首先针对传统神经网络层数多、计算复杂等问题,构造轻量级神经网... 针对点云分类分割方法中存在的高计算开销、复杂网络模型等问题,提出一种基于轻量级网络和加权随机森林(RF)的点云分类分割算法。该算法采用层次化的方式实现高效分类分割,首先针对传统神经网络层数多、计算复杂等问题,构造轻量级神经网络,并利用其提取点云的全局形状、区域间关系、曲率、法向量和颜色等特征,实现点云的快速粗分类分割;然后针对数据不平衡的问题,设计自适应分类分割策略,并引入加权RF,结合不一致度量筛选与动态加权优化机制,以实现点云精分类分割。在ModelNet40数据集上进行分类实验,在Semantic3D数据集和室外场景点云数据上进行了分割实验,结果表明,相比Local Geo-Transformer,PointNeXt和FastPointNet++等算法,该算法的分类分割精度分别提高了约1.9%,1.6%和1.7%,分类分割时间分别降低了约40%,30%和20%。由此可见,基于轻量级网络和加权RF的点云分类分割算法在保持较高分类分割精度的同时,可以有效缩短模型的训练时间,提高分类分割效率,是一种有效的点云分类分割算法。 展开更多
关键词 点云分类分割 轻量级网络 加权随机森林 全局形状 曲率
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Modified fuzzy point estimate method and its application to slope reliability analysis 被引量:2
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作者 Wenhui Tan, Meifeng Cai, and Rudi ZhouCivil and Environmental Engineering School, University of Science and Technology Beijing, Beijing100083, China 《Journal of University of Science and Technology Beijing》 CSCD 2003年第6期5-10,共6页
A slope engineering system is a complex system, in which many uncertaintiesexist, including random uncertainties and fuzzy uncertainties. Traditionally, random uncertaintieswere often considered, while fuzzy uncertain... A slope engineering system is a complex system, in which many uncertaintiesexist, including random uncertainties and fuzzy uncertainties. Traditionally, random uncertaintieswere often considered, while fuzzy uncertainties were ignored. Therefore, fuzzy-random methodsshould he proposed. A fuzzy point estimate method was proposed by Dodagoudar, that is, consideringthe effect of fuzzy-random factors, the fuzzy-random limit state function of slopes is changed torandom interval limit state function by the lambda level cutting, then the moments of the functioncan be obtained by the Rosenblueth's method, and the stability state of slopes can be evaluated bysynthesizing a group of moments. But in Dodagoudar's method, Rosenblueth's state function iscomposed of only two kinds of combinations of parameters rather than 2~n kinds of combinations. So amodified fuzzy point estimate method is proposed by the authors, and it is used in a slopereliability analysis. 展开更多
关键词 slope reliability fuzzy-random uncertainties modified fuzzy point estimatemethod
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RANDOM APPROXIMATION OF AN ADDITIVE FUNCTIONAL EQUATION OF m-APPOLLONIUS TYPE 被引量:2
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作者 Hassan Azadi Kenary 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1813-1825,共13页
In this paper,using the fixed-point and direct methods,we prove the HyersUlam stability of the following m-Appolonius type functional equation:∑mi=1 f(z-xi)=mf(z-1/m2∑mi=1xi)-1/m∑1≤i〈j≤mf(xi+xj),where m ... In this paper,using the fixed-point and direct methods,we prove the HyersUlam stability of the following m-Appolonius type functional equation:∑mi=1 f(z-xi)=mf(z-1/m2∑mi=1xi)-1/m∑1≤i〈j≤mf(xi+xj),where m is a natural number greater than 1,in random normed spaces. 更多还原 展开更多
关键词 Hyers-Ulam stability additive functional equation random normed space fixed point method
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