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Supply Chain Finance Credit Risk Evaluation Method Based on Self-Adaption Weight 被引量:4
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作者 Yueliang Su Nan Lu 《Journal of Computer and Communications》 2015年第7期13-21,共9页
Credit risk is the core issue of supply chain finance. In the supply chain, problems happened in different enterprises can influent the whole to different degrees through transferring, thus statuses of all enterprises... Credit risk is the core issue of supply chain finance. In the supply chain, problems happened in different enterprises can influent the whole to different degrees through transferring, thus statuses of all enterprises and their different influences should be considered when evaluating the supply chain’s credit risk. We examine the characters of supply chain network and complex network, use the local growing complex network to simulate the real supply chain, use cluster analysis to classify the company into several levels;Introducing each level’s self-adaption weight formula according to the company’s quantity and degrees of this level and use the weight to improve the credit evaluation method. The research results indicate that complex network can be used to simulate the supply chain. The credit risk evaluation (CRE) of an enterprise level with bigger note degrees has a greater weight in the supply chain system’s CRE, thus has greater effect on the whole chain. Considering different influences of different enterprise levels can improve credit risk evaluation method’s sensitivity. 展开更多
关键词 Supply CHAIN FINANCE CREDIT RISK self-Adaption weight Complex Network
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基于Self-Weight与t-SNE的滚动轴承故障诊断
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作者 倪伟 蒋占四 《桂林电子科技大学学报》 2022年第6期463-467,共5页
针对滚动轴承故障信号非线性、故障特征种类繁多难以准确分类的问题,提出了一种Self-Weigh与t-SNE相结合的解决方法。先用WPT完成对原始故障信号的处理及特征的提取,然后采用Self-Weigh评估每个特征的敏感程度,获取最优特征;再对这些最... 针对滚动轴承故障信号非线性、故障特征种类繁多难以准确分类的问题,提出了一种Self-Weigh与t-SNE相结合的解决方法。先用WPT完成对原始故障信号的处理及特征的提取,然后采用Self-Weigh评估每个特征的敏感程度,获取最优特征;再对这些最优特征通过t-SNE进行降维可视化处理,获取低维敏感特征,并将其作为AP传播聚类的输入,从而实现故障类型100%正确识别。采用机械综合模拟实验平台的轴承数据加以验证,并与采用t-SNE、Self-Weigh+PCA方法进行对比,结果体现了所提方法的优势。 展开更多
关键词 自权重 t分布随机近邻嵌入 滚动轴承 故障诊断 特征提取
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SIMILARITY SOLUTION OF SELF-WEIGHT CONSOLIDATION PROBLEM FOR SATURATED SOIL
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作者 谢新宇 张继发 曾国熙 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第9期1165-1171,共7页
A more general assumption than that in the classical one-dimensional large strain consolidation theory is adopted and the exact analytical solution of nonlinear finite strain self-weight consolidation based on this as... A more general assumption than that in the classical one-dimensional large strain consolidation theory is adopted and the exact analytical solution of nonlinear finite strain self-weight consolidation based on this assumption is obtained. By applying the same experimental data, the comparison of the solutions of linear and nonlinear finite strain theory, as well as the numerical calculating results based on finite element method is presented. The results of the comparison show that the analytical solution obtained here takes on better agreement with practical cases than that of linear one, and they also show that, compared with the solutions based on nonlinear theory, the settlement and the consolidation degree based on linear theory are smaller. 展开更多
关键词 self-weight consolidation Burgers equation large stlain Lie group transformation similarity solution
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Structure and Properties of Self-reinforced Material Made from Ultra-high Molecular Weight Polyethylene-montmorillonite Nanocomposite 被引量:3
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作者 WANGQing-zhao LIAOXian-ling LIUZong-lin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第4期504-510,共7页
High-strength and high-modulus ultra-high molecular weight polyethylene(UHMWPE), named self-reinforced material, was obtained by the elongation of UHMWPE-montmorillonite nanocomposite at melting temperature. According... High-strength and high-modulus ultra-high molecular weight polyethylene(UHMWPE), named self-reinforced material, was obtained by the elongation of UHMWPE-montmorillonite nanocomposite at melting temperature. According to the scanning electron microscope(SEM) analysis, a great deal of fibrillar texture formed in the direction of elongation, and the tensile fractured surface was similar to that of highly oriented fiber. The transmission electron microscope(TEM) and selective area electron diffraction(SAED) analyses reveal that the reinforced phase of the self-reinforced material is an extended chain crystal and its size is about 50_200 nm wide and several microns long, and the montmorillonite layers are broken up to pieces in the size from 100 to 10 nm. The broken layers which have a huge surface area interacting strongly with macromolecules reduces the entanglement density of UHMWPE and induces the chain orientation in flow field. It is supposed that the astriction of montmorillonite layers to polyethylene chains is not only end-tethered but also side-tethered. The differential scan calorimetry(DSC) analysis shows that there are two endothermal peaks for the self-reinforced material, of which the peak at a higher temperature(136.4 ℃) is ascribed to the melting of the reinforced phase. 展开更多
关键词 Ultra-high molecular weight polyethylene-montmorillonite nanocomposite ELONGATION self-reinforced material Properties Structure
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Self-determinate evaluation method based on condition of weights non-dictatorial rate 被引量:3
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作者 Zhang Danning Yi Pingtao Guo Yajun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期310-320,共11页
The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes ... The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes simulating the model of economic man's self-benefit bahaviors, taking the place of experts to evaluate, bringing in the model of minimizing the sum of included angles to integrate the information of multiple objects and put the objects in order finally. The method has the advangtages of less dependendence on the subjective information, plenty of information, fair process and simple caculating. Finally, an application example is given to illustrate the effectiveness of the proposed method. 展开更多
关键词 condition of weights non-dictatorial rate principle of competitive view optimization self-determinate evaluation comprehensive evaluation
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Impact of Pharmaceutical Care on Self-Administration of Outpatient Low-Molecular-Weight Heparin Therapy
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作者 Seraina Mengiardi Dimitrios A. Tsakiris +4 位作者 Viviane Molnar Urs Kohlhaas-Styk Michael Mittag Stephan Kraehenbuehl Kurt E. Hersberger 《Pharmacology & Pharmacy》 2014年第4期372-385,共14页
Outpatient subcutaneous (s.c.) therapies are becoming more and more common in the treatment of different diseases. The effectiveness of community-pharmacy-based interventions in preventing problems that arise during s... Outpatient subcutaneous (s.c.) therapies are becoming more and more common in the treatment of different diseases. The effectiveness of community-pharmacy-based interventions in preventing problems that arise during s.c. self-injections of low-molecular-weight heparins (LMWH) is unknown. Our objective was to provide a standard operating procedure (SOP) for community pharmacists and to compare pharmaceutical vs. standard care in both clinical and daily life settings. We hypothesized that: pharmaceutical care results in improved adherence, safety, and satisfaction, and in fewer complications;the interventions used are feasible in daily life;and the results achieved in clinical and daily life settings are comparable. In the clinical setting (randomized controlled trial), patients were recruited sequentially in hospital wards;in the daily life setting (quasi-experimental design with a comparison group), recruitment took place in community pharmacies by pharmacists and trained master students during their internship. Interventions were offered according to patient needs. Data were collected by means of a monitored self-injection at home and structured questionnaire-based telephone interviews at the beginning and the end of the LMWH treatment. The main outcome measures were: scores to assess patient’s skills;syringe count to assess adherence;and frequency, effectiveness, and patient’s assessment of received interventions. The results show a median age of the 139 patients of 54 years. Interventions resulted in improved application quality (p p = 0.03). Oral instructions were pivotal for improving patients’ application quality. We found no significant score differences between the intervention groups in the clinical and daily life settings. Patients’ baseline skills were high, with the lowest score being 0.86 (score range ?2.00 to +2.00). Adherence rate was high (95.8%). In conclusion, our SOP for pharmacist interventions was of good quality, adequate, appreciated, and feasible in daily life. Patients are capable of managing s.c. injection therapies if adequate assistance is provided. 展开更多
关键词 LOW-MOLECULAR-weight Heparin OUTPATIENTS SUBCUTANEOUS Injections self Administration Pharmaceutical Care Community PHARMACY Switzerland
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基于Vision Transformer的车辆重识别模型优化
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作者 张震 张亚斌 田鸿朋 《郑州大学学报(理学版)》 CAS 北大核心 2025年第1期46-52,共7页
针对车辆重识别任务中样本类内差异性大和类间相似度高的问题,提出了一种Vision Transformer框架下的车辆重识别方法。设计一种关键区域选择模块,整合Transformer中注意力分数矩阵,加强车辆的具有辨别性区域的关注程度,减小局部区域过... 针对车辆重识别任务中样本类内差异性大和类间相似度高的问题,提出了一种Vision Transformer框架下的车辆重识别方法。设计一种关键区域选择模块,整合Transformer中注意力分数矩阵,加强车辆的具有辨别性区域的关注程度,减小局部区域过度集中的注意力权重;构建一种包含对比损失和中心损失的混合损失函数,对比损失函数的引入增强了模型捕捉和比较样本之间的差异的能力,中心损失使得同一类别的样本更加紧密地聚集在一起,增强类间样本的区分度。实验结果验证了其有效性。 展开更多
关键词 车辆重识别 自注意力机制 注意力权重 区域选择
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模内贴标快餐碗微发泡模流仿真研究析
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作者 施小庆 杨均才 陈炽辉 《橡塑技术与装备》 CAS 2025年第1期54-58,共5页
本文采用Moldex3D软件,模拟了带自锁射嘴、一模两腔、模内贴标快餐碗的微发泡工艺。分析了快餐碗的注塑压力、减重百分比及泡孔尺寸,与实际情况对比,有较好的准确性。
关键词 模内贴标快餐碗 微发泡模流仿真 MOLDEX3D 自锁射嘴 注塑压力 减重 泡孔尺寸
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Patient attitudes about financial incentives for diabetes self-management:A survey 被引量:2
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作者 Katherine S Blondon 《World Journal of Diabetes》 SCIE CAS 2015年第5期752-758,共7页
AIM:To study the acceptability of incentives for behavior changes in individuals with diabetes,comparing financial incentives to self-rewards and non-financial incentives.METHODS:A national online survey of United Sta... AIM:To study the acceptability of incentives for behavior changes in individuals with diabetes,comparing financial incentives to self-rewards and non-financial incentives.METHODS:A national online survey of United States adults with diabetes was conducted in March 2013(n = 153).This survey was designed for this study,with iterative testing and modifications in a pilot population.We measured the demographics of individuals,their interest in incentives,as well as the perceived challenge of diabetes self-management tasks,and expectations of incentives to improve diabetes self-management(financial,non-financial and self-rewards).Using an ordered logistic regression model,we assessed the association between a 32-point score of the perceived challenge of the self-management tasks and the three types of rewards.RESULTS:Ninety-six percent of individuals were interested in financial incentives,60% in non-financial incentives and 72% in self-rewards.Patients were less likely to use financial incentives when they perceived the behavior to be more challenging(odds ratio of using financial incentives of 0.82(95%CI:0.72-0.93) for each point of the behavior score).While the effectiveness of incentives may vary according to the perceived level of challenge of each behavior,participants did not expect to need large amounts to motivate them to modify their behavior.The expected average amounts needed to motivate a 5 lb weight loss in our population and to maintain this weight change for a year was $258(interquartile range of $10-100) and $713(interquartile range of $25-250) for a 15 lb weight loss.The difference in mean amount estimates for 5 lb and 15 lb weight loss was significant(P < 0.001).CONCLUSION:Individuals with diabetes are willing to consider financial incentives to improve diabetes selfmanagement.Future studies are needed to explore incentive programs and their effectiveness for diabetes. 展开更多
关键词 PATIENT INCENTIVES DIABETES self-MANAGEMENT MOTIVATION weight loss PATIENT ENGAGEMENT
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Real-Time Update of Sequence Placement Logic for High Arch Dams Based on Evidence Weight Discount 被引量:1
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作者 Tao Guan Denghua Zhong Bingyu Ren 《Transactions of Tianjin University》 EI CAS 2017年第3期267-276,共10页
Sequence placement logic plays a significant role in construction simulation of high arch dams and directly affects the simulation process and results. To establish a sequence logic for dam block placement, the constr... Sequence placement logic plays a significant role in construction simulation of high arch dams and directly affects the simulation process and results. To establish a sequence logic for dam block placement, the construction scheme, real-time construction process, and random factors of the site all need to be considered in detail. There are few studies available currently that take all these factors into consideration. To address this problem, a real-time update of sequence placement logic for high arch dams based on evidence weight discount is proposed in this study. First, the subjective weight of the dam block sequence priority criteria is built using a consistent matrix method based on the construction scheme. Second, using evidence theory, dynamic objective weight of the priority criteria and basic probability assignment is built. Finally, using a weight self-adaptive adjustment method and comprehensive evidence discounting, the placing probabilities of different dam blocks are obtained. A case study indicates that this method can realize real-time update of sequence placement logic. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Arch dams ARCHES DAMS
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自适应相似图联合优化的多视图聚类
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作者 纪霞 施明远 +1 位作者 周芃 姚晟 《计算机学报》 EI CSCD 北大核心 2024年第2期310-322,共13页
相比于单一视图学习,多视图学习往往可以获得学习对象更全面的信息,因而在无监督学习领域,多视图聚类受到了研究者的极大关注,其中基于图的多视图聚类,近年来取得了很大的研究进展.基于图的多视图聚类一般是先从各个视图原始数据学习相... 相比于单一视图学习,多视图学习往往可以获得学习对象更全面的信息,因而在无监督学习领域,多视图聚类受到了研究者的极大关注,其中基于图的多视图聚类,近年来取得了很大的研究进展.基于图的多视图聚类一般是先从各个视图原始数据学习相似图,再进行视图间相似图的融合来获得最终聚类结果,因此,多视图聚类的效果是由相似图质量和相似图融合方法共同决定的.然而,现有基于图的多视图聚类方法几乎都聚焦在视图间相似图的融合方法研究上,而缺乏对相似图本身质量的关注.这些方法大多数都是孤立地从各视图的原始数据中学习相似图,并且在后续图融合过程中保持相似图不变.这样得到的相似图不可避免地包含噪声和冗余信息,进而影响后续的图融合和聚类.而少量考虑相似图质量的研究,要么相似图构造和图融合过程是直接联立迭代的,要么在预定义相似图过程中提前利用秩约束进一步初始化,要么就是利用相似图存在的一些底层结构来获取融合图的.这些方法对相似图本身改进很小,最终聚类性能提升也十分有限.同时现有基于图的多视图聚类流程也缺乏对各视图间一致性和不一致性的综合考虑,这也会严重影响最终的多视图聚类性能.为了避免低质量预定义相似图对聚类结果的不利影响以及综合考虑视图间一致性与不一致性来提升最终聚类效果,本文提出了一种自适应相似图联合优化的多视图聚类方法.首先通过Hadamard积来获得视图间高质量一致性部分信息,再将每个预定义相似图和这部分信息对标,重构各个视图的预设相似图.这个过程强化了各视图间的一致性部分,弱化了不一致性部分.其次设计了相似图重构改进和图融合联合迭代优化框架,实现了相似图的自适应改进,最终达到相似图和聚类结果共同提升的效果.该方法将相似图改进过程与图融合过程联合起来进行自适应迭代优化,并且在迭代优化中不断强化各视图间的一致性,弱化视图间的不一致性.此外,本文的方法也集成了现有多视图聚类方法的一些优点,自加权以及无需额外聚类步骤等.在九个基准数据集上与八个对比方法的实验验证了本文方法的有效性与优越性. 展开更多
关键词 多视图聚类 相似图 自适应优化 图融合 自加权
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基于SAW-PCL的输电线路缺销螺栓弱监督检测方法
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作者 赵振兵 马迪雅 +3 位作者 丁洁涛 翟永杰 赵文清 张珂 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第11期3319-3326,共8页
螺栓作为输电线路中不可或缺的紧固件,其缺销必然会引起重大的安全隐患。针对螺栓目标较小、标注难度大的问题,提出了一种基于SAW-PCL的输电线路缺销螺栓弱监督检测方法。该方法通过图像级标注信息即可定位到螺栓目标。在主网络中引入... 螺栓作为输电线路中不可或缺的紧固件,其缺销必然会引起重大的安全隐患。针对螺栓目标较小、标注难度大的问题,提出了一种基于SAW-PCL的输电线路缺销螺栓弱监督检测方法。该方法通过图像级标注信息即可定位到螺栓目标。在主网络中引入卷积块注意模块(CBAM),抑制无用的背景特征,提取螺栓精细特征,提高螺栓的检测能力。针对弱监督检测中缺销螺栓的检测精度远低于正常螺栓及不平衡性问题,提出自适应加权损失函数(SAW),动态调节模型对不同类别样本的学习程度,均衡不同类别之间的检测精度,并定义了平均类间检测精度差(ADPD)来评价不平衡性。构建的自适应加权损失函数可以提升缺销螺栓的检测精度,对正常螺栓和缺销螺栓的检测精度有一定的均衡能力,定义的ADPD可以评价模型检测性能的平衡度。在自建数据集V1上的实验结果表明:改进方法的平均准确率均值(mAP)提高了19.7%,ADPD值降低了21.8,在mAP和ADPD双重指标评估下的模型表现出了更好的缺销螺栓检测能力。 展开更多
关键词 缺销螺栓检测 弱监督 平均类间检测精度差 自适应加权损失函数 深度学习
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膨润土胶体在处置库围岩裂隙中的扩散模型研究
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作者 陈宝 向平 邓荣升 《岩土力学》 EI CAS CSCD 北大核心 2024年第2期433-442,共10页
为了预测膨润土胶体在甘肃北山高放废物深地质处置库围岩裂隙中的扩散过程,提出了综合考虑膨润土胶体颗粒自重与水化力的扩散模型。研究了钠离子浓度、水化力、胶体颗粒自重以及蒙脱石体积分数对膨润土胶体的扩散过程和扩散系数的影响... 为了预测膨润土胶体在甘肃北山高放废物深地质处置库围岩裂隙中的扩散过程,提出了综合考虑膨润土胶体颗粒自重与水化力的扩散模型。研究了钠离子浓度、水化力、胶体颗粒自重以及蒙脱石体积分数对膨润土胶体的扩散过程和扩散系数的影响。研究结果表明:随着钠离子浓度的增加,膨润土胶体的扩散速率与扩散距离均减小。胶体颗粒自重越大,对扩散的影响越大。随着扩散的进行,水化力对扩散的影响逐渐减小,范德华力和扩散双电层力对扩散的影响逐渐增大,膨润土胶体的扩散系数整体表现为先减小后增大。当蒙脱石体积分数较小时(φ<0.45),随着钠离子浓度的增加,扩散系数整体上逐渐增大;当蒙脱石体积分数较大时(φ>0.45),钠离子浓度对扩散系数的影响较小。 展开更多
关键词 膨润土胶体 胶体扩散模型 扩散系数 颗粒自重 水化力
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湿陷性黄土场地中单桩承载力与负摩阻力试验研究
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作者 朱彦鹏 李芳川 +3 位作者 成栋 房光文 吴林平 韦正德 《建筑科学与工程学报》 CAS 北大核心 2024年第6期140-151,共12页
为了研究湿陷性黄土场地中土体湿陷引起的桩基承载力问题,在平凉市某工程现场利用机械成孔灌注桩(桩径0.8 m,桩长26 m)进行荷载-特殊浸水试验,对试验过程中不同深度处的桩身轴力和桩侧摩阻力进行分析。结果表明:天然状态下试验桩极限承... 为了研究湿陷性黄土场地中土体湿陷引起的桩基承载力问题,在平凉市某工程现场利用机械成孔灌注桩(桩径0.8 m,桩长26 m)进行荷载-特殊浸水试验,对试验过程中不同深度处的桩身轴力和桩侧摩阻力进行分析。结果表明:天然状态下试验桩极限承载力大于13 200 kN,受力特性为典型的摩擦桩;由于前期泥浆护壁施工方式对孔壁的浸水影响以及桩周土沿桩长方向上物理力学性能分布的不确定性,侧摩阻力沿深度出现多个峰值,最大值均出现在泥浆护壁以上(桩身2~6 m)位置处;在渗水孔与渗水坑相结合的特殊浸水试验条件下,桩侧负摩阻力在浸水试验第8 d时趋于稳定,中性点在桩身8 m位置处,负摩阻力为107.6 kPa;试验过程中桩周土沿桩长分段发生湿陷,而不是随浸水自上到下逐渐湿陷;受到预浸水作用的试件SZH在静载试验结束后的中性点出现在桩身12 m位置处,负摩阻力为127.8 kPa,人工浸水试验主要使桩身8 m位置以上桩身轴力增大,中性点位置保持不变,表明负摩阻力受桩顶荷载、浸水方式和浸水固结时间影响显著。 展开更多
关键词 桩基础 承载特性 试验研究 自重湿陷性黄土 负摩阻力 特殊浸水
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阴阳调理灸联合自我管理在更年期肥胖患者中的应用效果
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作者 黄蓓 周金波 +3 位作者 王芸 柳枝 罗湘 李彩虹 《中西医结合护理(中英文)》 2024年第6期45-48,共4页
目的探究更年期肥胖患者应用阴阳调理灸联合自我管理的干预效果,评估该方法对患者体重产生的影响。方法选取2021年1月至2022年12月在湖北省中医院接受诊治的60例更年期肥胖患者为研究对象,以随机数字表法为分组方式,分为对照组和观察组,... 目的探究更年期肥胖患者应用阴阳调理灸联合自我管理的干预效果,评估该方法对患者体重产生的影响。方法选取2021年1月至2022年12月在湖北省中医院接受诊治的60例更年期肥胖患者为研究对象,以随机数字表法为分组方式,分为对照组和观察组,各30例。对照组接受自我管理,观察组实施阴阳调理灸联合自我管理。比较2组的体格检查指标、生活质量和体质症状评分。结果干预12周后,观察组的体格检查指标(体重、腰围、体脂和臀围)测定数值均较对照组更小(P均<0.05),且2组的体格检查指标均优于干预前(P均<0.05)。干预12周后,2组的体重对生活冲击量表(IWQOL)各维度评分均低于干预前(P均<0.05);对比组间IWQOL评分,均为观察组更低(P均<0.05)。干预12周后,2组患者的额头分泌油脂多等体质症状评分均较干预前降低(P均<0.05),且观察组均低于对照组(P均<0.05)。结论阴阳调理灸联合自我管理可调理更年期肥胖患者的体质,改善其体格检查指标,减轻肥胖对于患者日常生活产生的影响。 展开更多
关键词 更年期 肥胖 阴阳调理灸 自我管理 体重
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100 m~150 m跨混凝土拱桥基于特定钢拱架的预拱度快速计算方法
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作者 周水兴 吴文滔 +1 位作者 陈德果 韩洪举 《公路交通技术》 2024年第1期95-100,106,共7页
针对100 m~150 m跨混凝土拱桥所采用的特定钢拱架的预拱度计算问题,提出了一种用拱圈自重变形和钢拱架变形比值快速计算钢拱架预拱度的方法。为了得到不同矢跨比和拱轴系数下的钢拱架变形比值,编写了通过导入MCT文件建立Midas/Civil有... 针对100 m~150 m跨混凝土拱桥所采用的特定钢拱架的预拱度计算问题,提出了一种用拱圈自重变形和钢拱架变形比值快速计算钢拱架预拱度的方法。为了得到不同矢跨比和拱轴系数下的钢拱架变形比值,编写了通过导入MCT文件建立Midas/Civil有限元模型的辅助程序,实现从单元、边界条件、施工阶段和施工阶段联合截面定义的全过程快速建模,对拱圈混凝土分底板、腹板、顶板三环浇筑,考虑钢拱架与拱圈的联合作用,给出了钢拱架预拱度计算公式。计算结果表明,对于常用矢跨比和拱轴系数的混凝土拱桥,拱圈分环浇筑变形与拱圈自重变形比值的平均值为4.37~4.88,为方便钢拱架弹性变形计算,建议变形比值统一取5.0。将该方法应用于一座净跨径为135 m的混凝土拱桥钢拱架预拱度计算中,得到的钢拱架弹性变形与空间模型结果最大误差为4.30%,满足工程精度要求,表明该方法合理可行,可在混凝土拱桥钢拱架预拱度计算中推广应用。 展开更多
关键词 混凝土拱桥 钢拱架 分环浇筑 预拱度计算 变形比值 拱圈自重变形
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基于Self-adjust网络模型的人脸图像情感分析方法 被引量:1
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作者 邓亚萍 王新 +2 位作者 尹甜甜 王婷 郑承宇 《河南工程学院学报(自然科学版)》 2022年第1期61-65,75,共6页
人脸表情具有丰富的情感内涵,是情感分析的一个重要研究方向。模糊的面部表情及标注者的主观性所带来的不确定性,给情感分析研究带来了挑战。鉴于此,提出了一种基于Self-adjust网络模型的人脸图像情感分析方法。首先用人脸对齐方法进行... 人脸表情具有丰富的情感内涵,是情感分析的一个重要研究方向。模糊的面部表情及标注者的主观性所带来的不确定性,给情感分析研究带来了挑战。鉴于此,提出了一种基于Self-adjust网络模型的人脸图像情感分析方法。首先用人脸对齐方法进行图像预处理,然后利用注意力机制来处理Focal损失加权,再对其进行秩正则化排序,最后通过重新分类对有误标签进行矫正,并用实验验证了该方法的有效性与优越性。该方法在准确率这个评价指标上有所提高,能够有效抑制人脸图像情感分析的不确定性,防止深层网络对不确定的人脸图像进行过拟合。 展开更多
关键词 self-adjust网络模型 人脸对齐 注意力机制 Focal损失加权 情感分析
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基于IWOA算法的矿井风量智能优化研究
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作者 张景钢 何鑫 林桂玲 《矿业安全与环保》 北大核心 2024年第6期177-184,191,共9页
为解决复杂矿井通风网络中存在的风量分配不合理、通风调节设施设置不当,以及通风功耗高等问题,基于图论与通风网络理论,构建以矿井通风网络风量分配基本定律、通风巷道风量风压、主要通风机运行工况为约束条件,以矿井通风网络运行功耗... 为解决复杂矿井通风网络中存在的风量分配不合理、通风调节设施设置不当,以及通风功耗高等问题,基于图论与通风网络理论,构建以矿井通风网络风量分配基本定律、通风巷道风量风压、主要通风机运行工况为约束条件,以矿井通风网络运行功耗最低为目标函数的矿井通风网络非线性优化数学模型,并运用罚函数法将约束条件转换为目标函数的惩罚项。在标准鲸鱼群优化算法的基础上,提出一种融合混沌反向学习、Beta分布、非线性自适应惯性权重的多策略改进方法,通过提高算法的求解精度与收敛速度,增强算法的局部开发与全局寻优能力。采用改进鲸鱼群(IWOA)算法对模型进行求解,并将冀中能源股份有限公司邢东煤矿通风系统作为研究对象进行模拟,结果表明:该煤矿的矿井通风网络运行总功耗下降13.43%,矿井各用风巷道风量分布合理,符合矿井实际通风需求,证明所采用算法的可行性与优异性。 展开更多
关键词 矿井通风 风量智能优化 改进鲸鱼群算法 非线性自适应权重 混沌反向学习 BETA分布
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改进GSA算法在机器人路径规划中的应用研究 被引量:1
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作者 樊康生 杨光永 徐天奇 《组合机床与自动化加工技术》 北大核心 2024年第7期44-50,共7页
针对万有引力搜索算法(GSA)收敛精度低和易陷入局部最优等问题,提出一种改进万有引力搜索算法(IGSA)。引入当前迭代次数t动态调整引力常数,以增强算法逃离局部最优能力;基于边界值改进粒子越界处理策略,以保留粒子多样性,提高算法收敛精... 针对万有引力搜索算法(GSA)收敛精度低和易陷入局部最优等问题,提出一种改进万有引力搜索算法(IGSA)。引入当前迭代次数t动态调整引力常数,以增强算法逃离局部最优能力;基于边界值改进粒子越界处理策略,以保留粒子多样性,提高算法收敛精度;同时,将中垂线算法用于游离粒子的位置更新,以加速游离粒子的收敛;为适应前述策略,提出自适应权重因子更新粒子位置策略,以提高算法的收敛速度。算法在10个基准测试函数上的结果表明,改进算法在稳定性、收敛速度和精度方面具有较大优势。最后将改进算法应用于机器人路径规划,并与其他智能仿生算法进行路径规划仿真对比实验,结果表明本文改进算法规划路径更短、拐点更少、搜索效率更高。 展开更多
关键词 引力常数 中垂线算法 自适应权重因子 路径规划
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PDCA在降低患者自行注射预灌式低分子肝素钠皮下瘀斑发生率中的应用效果
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作者 张玉珍 黄艳慧 吴荣锋 《中国卫生标准管理》 2024年第20期189-193,共5页
目的探讨开展计划-实施-检查-处理(plan-do-check-act,PDCA)循环在降低患者自行注射预灌式低分子肝素钠皮下瘀斑发生率中的应用效果。方法将2023年3—5月在厦门大学附属第一医院就诊并自行注射预灌式低分子肝素钠的56例患者作为对照组,... 目的探讨开展计划-实施-检查-处理(plan-do-check-act,PDCA)循环在降低患者自行注射预灌式低分子肝素钠皮下瘀斑发生率中的应用效果。方法将2023年3—5月在厦门大学附属第一医院就诊并自行注射预灌式低分子肝素钠的56例患者作为对照组,将2023年8—10月自行注射预灌式低分子肝素钠的49例患者作为观察组。对照组采用常规注射流程进行注射指导,观察组运用PDCA循环工具进行注射干预管理。比较2组自行注射预灌式低分子肝素钠皮下瘀斑的发生率。结果观察组注射部位未轮换发生率为20.4%,未带空气泡注射发生率为18.4%,按压手法不准确发生率为16.3%,进针深度不准确发生率为6.1%,按压时间不够发生率为4.1%,低于对照组的44.6%、39.3%、35.7%、19.6%、17.9%,差异有统计学意义(P<0.05)。观察组注射时疼痛程度优于对照组,差异有统计学意义(P<0.05)。观察组皮下瘀斑的发生率为12.2%,低于对照组的33.9%,差异有统计学意义(P<0.05)。结论PDCA循环工具的应用有助于降低患者自行注射预灌式低分子肝素钠皮下瘀斑的发生率。 展开更多
关键词 PDCA 降低 自行注射 预灌式低分子肝素钠 皮下瘀斑 发生率
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