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Multi-Symptom Relief for Cough & Cold: Benefits of Adding Vicks VapoRub to the Treatment Regimen
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作者 Delyth Whiteford Juana Rios +1 位作者 David Hengehold Sue Aspley 《Open Journal of Respiratory Diseases》 2023年第2期9-27,共19页
Background: The common cold is inarguably a multi-symptom syndrome. Thus, patients commonly use several medicinal products simultaneously to treat a range of co-existing clinical manifestations. Topical ointments... Background: The common cold is inarguably a multi-symptom syndrome. Thus, patients commonly use several medicinal products simultaneously to treat a range of co-existing clinical manifestations. Topical ointments with medicated vapours are a popular and effective treatment for the relief of various respiratory tract symptoms. Vicks VapoRub (VVR), a paraffin-based therapeutic ointment containing levomenthol, eucalyptus oil, turpentine oil and camphor, is frequently combined with other cough and cold treatments. However, little is known about which medications are commonly taken together and how patients experience the combined efficacy. Methods: A 20-question online survey to assess habits and beliefs amongst cold sufferers was conducted using the Toluna Start platform. A total of 1513 adults that had suffered from a cold or mild COVID-19 infection in the preceding 12 months were recruited from five European countries. Results: Most cold sufferers combined VVR with other cold medicines, such as paracetamol (75.9%), multi-symptom relief (MSR) products (64.0%) or nasal decongestants (57.0%) to treat their symptoms. VVR was mainly used topically, at night, and on days 3 - 4 of the disease. The addition of VVR to the treatment regimen was perceived as highly effective at relieving multiple cold symptoms. Furthermore, improved sleep and a free breathing sensation were attributed to VVR when used in combination with other cold remedies. Statements on VVR regarding effectiveness, sleep, sleep + effectiveness, speed of action and user satisfaction were agreed upon by a total of 74.8% to 88.3% of panellists. Conclusion: Our survey confirms that in Europe, VVR is commonly used as part of a regimen to manage cold symptoms, and contributes to better overall perceived relief as part of a multi-facetted treatment approach. Prospective clinical data are needed to further confirm these results. 展开更多
关键词 Common Cold Vicks VapoRub Therapeutic Ointment Survey multi-symptom relief
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Rationale for Treatment of Common Cold and Flu with Multi-Ingredient Combination Products for Multi-Symptom Relief in Adults
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作者 Ron Eccles Ingo Fietze Uwe-Bernd Rose 《Open Journal of Respiratory Diseases》 2014年第3期73-82,共10页
This up-to-date overview will look at the rationale for the recommendation of combination products for multi-symptom relief of common cold and flu. Common cold and flu are defined by their multi-symptom nature with da... This up-to-date overview will look at the rationale for the recommendation of combination products for multi-symptom relief of common cold and flu. Common cold and flu are defined by their multi-symptom nature with data showing a variety of symptoms reported simultaneously each day over the first six days of illness. Multi-ingredient combination products for multi-symptom relief are formulated to safely, simply, and simultaneously treat multiple symptoms when used as directed. The rationale for the formulation combination products for common cold and flu is therefore practical, logical and reasonable. No evidence has been found that multi-symptom relief medicines are inherently less safe than single-active ingredient medicines. Multi-symptom relief combination products containing several active ingredients provide a safe, effective, cost-effective, and convenient way of treating the multiple symptoms of common cold and flu, when used as directed. This therapy requires some special information for the patient to be provided by the physician and the pharmacist. 展开更多
关键词 Combination Products multi-symptom relief Multi-Ingredient Common Cold FLU
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基于Relief-F特征优选的滑坡影响因子提取及易发性建模分析 被引量:1
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作者 方露 邢尹 《测绘通报》 北大核心 2025年第6期90-96,共7页
为解决现有滑坡易发性评价模型精度不足和单一决策模型局限性的问题,本文提出了一种集成智能组合算法优化RF的PSO-GA-RF集成模型。采用著名的过滤式特征选择方法——Relief-F算法,对滑坡致灾因子进行权重排序,剔除冗余特征,优化分类结果... 为解决现有滑坡易发性评价模型精度不足和单一决策模型局限性的问题,本文提出了一种集成智能组合算法优化RF的PSO-GA-RF集成模型。采用著名的过滤式特征选择方法——Relief-F算法,对滑坡致灾因子进行权重排序,剔除冗余特征,优化分类结果,从而减少了依赖主观判断提取影响因子的问题,降低了人为误差。PSO-GA-RF集成模型融合了多种算法的优势,对RF模型的参数进行优化,简化了参数选择的烦琐过程,减小了误差。试验结果表明,PSO-GA-RF集成模型在预测性能和效率上均优于RF和GA-RF模型。 展开更多
关键词 滑坡 易发性 影响因子 relief-F PSO-GA-RF
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一种用于遥感影像信息提取的改进Relief算法 被引量:1
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作者 王宇豪 曹红新 +2 位作者 秦增忍 王帆 朱镇 《遥感信息》 北大核心 2025年第1期71-78,共8页
针对Relief算法的特征权重受样本随机性影响较大、不适用于多类别间的特征选择且无法自动确定特征阈值等不足,提出了一种改进的Relief算法,用于面向对象的遥感影像信息提取。新算法基于正态分布改进Relief算法的样本抽样策略和特征权重... 针对Relief算法的特征权重受样本随机性影响较大、不适用于多类别间的特征选择且无法自动确定特征阈值等不足,提出了一种改进的Relief算法,用于面向对象的遥感影像信息提取。新算法基于正态分布改进Relief算法的样本抽样策略和特征权重更新方式,提出特征组合评判指标Cω用于多类别间特征选择,最后根据高斯混合模型自动确定特征的阈值。基于陕西省周至县地区无人机影像和湖北省巴东县地区高分六号影像的实例测试结果表明,IRelief算法不仅能有效对特征进行降维和精选,还能够自动计算特征在分类时的阈值,总体精度、Kappa系数以及其他精度评价指标均优于Relief和ReliefF算法,是一种更优的特征选择算法。 展开更多
关键词 relief 特征选择 面向对象 信息提取 正态分布 高斯混合模型
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融合K-means聚类和标记相关性的多标记Relief特征选择 被引量:1
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作者 丰昌武 孙林 《聊城大学学报(自然科学版)》 2025年第1期122-134,共13页
现有Relief算法在利用标记相关性方面存在不足,忽视了局部标记相关性所提供的宝贵信息。针对这一问题,提出了一种融合K-means聚类与标记相关性的多标记Relief特征选择方法。首先,为充分考虑样本标记相关性,采用K-means聚类算法对样本进... 现有Relief算法在利用标记相关性方面存在不足,忽视了局部标记相关性所提供的宝贵信息。针对这一问题,提出了一种融合K-means聚类与标记相关性的多标记Relief特征选择方法。首先,为充分考虑样本标记相关性,采用K-means聚类算法对样本进行聚类,将其划分到不同的簇中,从而构建样本的局部标记空间。其次,定义了所有样本在特征上的欧式距离,以此衡量样本的全局标记相关性。同时,改进了传统的余弦相似度,使用L1范数的平方根进行优化,并在局部标记空间中应用改进的余弦相似度,以有效获取样本的局部标记相关性。最后,在Relief算法的基础上,融合了样本的全局标记相关性与局部标记相关性,以此作为衡量样本相似度的依据,进而判别最近邻同类样本与最近邻异类样本,最终获得特征权重。为评估所提算法的性能,在10个多标记数据集上进行了对比测试,实验结果证明,与其他多标记特征选择算法相比,本算法具有显著优势。 展开更多
关键词 多标记学习 特征选择 K-MEANS聚类 标记相关性 relief算法
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基于Relief算法的仪器仪表故障图像自动识别方法研究 被引量:1
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作者 赵章龙 《仪器仪表用户》 2025年第2期48-50,共3页
常规的仪器仪表故障图像自动识别方法以图像分割为主,并未对正常图像与异常图像进行分类,影响了图像自动识别的准确性。为了解决这一问题,设计了基于Relief算法的仪器仪表故障图像自动识别方法。提取仪器仪表故障过程趋势特征,通过峭度... 常规的仪器仪表故障图像自动识别方法以图像分割为主,并未对正常图像与异常图像进行分类,影响了图像自动识别的准确性。为了解决这一问题,设计了基于Relief算法的仪器仪表故障图像自动识别方法。提取仪器仪表故障过程趋势特征,通过峭度值、差分趋势两方面,识别仪器仪表运行过程的异常值,从而确保故障识别的准确性。基于Relief标注仪器仪表故障图像自动识别区间,通过图像去噪、去雾等方式,得到更加准确图像,并利用Relief对图像进行分类,避免故障图像识别失误的问题。采用对比实验,验证了该方法的识别准确性更高,能够应用于实际生活中。 展开更多
关键词 relief算法 仪器仪表 仪表故障 故障图像 自动识别方法
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Advances in Residual Stress Relief Strategies at Ceramic/Metal Joint Interfaces
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作者 Wang Xingxing Chen Benle +4 位作者 Jiang Yuanlong Pan Kunming Ren Xuanru Yuan Zhipeng Zhang Yulei 《稀有金属材料与工程》 北大核心 2025年第3期618-627,共10页
As service conditions become more challenging and production complexity increases,there is an increasing demand for enhanced comprehensive performance of ceramic/metal heterostructures.At present,brazing technique has... As service conditions become more challenging and production complexity increases,there is an increasing demand for enhanced comprehensive performance of ceramic/metal heterostructures.At present,brazing technique has been widely utilized for ceramic-metal heterogeneous joints.However,the residual stress relief in these welding joints is complicated and necessary.Because metals and ceramics have different properties,especially their coefficients of thermal expansion.Welding joints exhibit large residual stresses during the cooling process.The relatively high residual stresses may significantly degrade the joint properties.For this issue,four alleviation routes were reviewed:optimization of process parameters,setting an intermediate layer,surface structure modulation and particle-reinforced composite solder.The states and distribution patterns of residual stress in ceramic-metal brazed joints were summarized,and the generation and detection of residual stress were introduced.Eventually,upcoming prospects and challenges of residual stress research on ceramic/metal heterostructures were pointed out. 展开更多
关键词 ceramics METALS BRAZING interfacial residual stress stress relief
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Chinese NGOs Actively Participated in Myanmar Earthquake Relief
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《International Understanding》 2025年第2期52-53,共2页
After the earthquake struck Myanmar on March 28th,China NGO Network for International Exchanges(CNIE)immediately contacted the emergency management department for the registration process of non-governmental rescue fo... After the earthquake struck Myanmar on March 28th,China NGO Network for International Exchanges(CNIE)immediately contacted the emergency management department for the registration process of non-governmental rescue forces participating in earthquake relief work and guided its member organisations and partners to orderly participate in the disaster relief. 展开更多
关键词 Chinese NGOs disaster relief Myanmar earthquake relief emergency management department registration process China NGO Network International Exchanges
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Finite element analysis and optimization of the rubber diaphragms in type-120 relief valves
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作者 Ming Gao Dongkai Li +5 位作者 Kun Liu Lijun Liu Ben Guo Anhui Pan Xiao Xie Huanre Han 《Railway Sciences》 2025年第5期598-612,共15页
Purpose–Type-120 relief valves are critical components of locomotive braking systems,and they rapidly discharge the air pressure during brake release to enable swift pressure relief.In order to develop type-120 relie... Purpose–Type-120 relief valves are critical components of locomotive braking systems,and they rapidly discharge the air pressure during brake release to enable swift pressure relief.In order to develop type-120 relief valve rubber diaphragms with long life and high performance,the damaged faulty samples were analyzed and studied.Design/methodology/approach–Finite element analysis(FEA)was used to investigate the stress distribution and failure mechanism of the rubber diaphragms within the type-120 relief valves under dynamic loading conditions.The Ogden hyperelastic constitutive model was used to fit the diaphragm data obtained from the uniaxial tensile tests,and its suitability for the modeling of large deformations was confirmed.Findings–The FEA results indicated that,when the rubber diaphragms reached their maximum deformation,the peak stress on their upper surfaces was 5.44 MPa.Thus,this region is highly susceptible to fatigue damage.The service life of the rubber diaphragms could be extended by using rubber compounds with high tensile moduli or a fabric-reinforced rubber diaphragm.Originality/value–This study provides valuable data and experience for the development of the rubber diaphragms in the type-120 valves and other long-life rubber products in the railway field. 展开更多
关键词 Type-120 relief valve Rubber diaphragm Damage failure Finite element analysis
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Application of a relief-optimized method for target space exteriorization sampling in landslide susceptibility assessment
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作者 CUI Yulong DENG Qining MIAO Haibo 《Journal of Mountain Science》 2025年第9期3391-3407,共17页
Selection of negative samples significantly influences landslide susceptibility assessment,especially when establishing the relationship between landslides and environmental factors in regions with complex geological ... Selection of negative samples significantly influences landslide susceptibility assessment,especially when establishing the relationship between landslides and environmental factors in regions with complex geological conditions.Traditional sampling strategies commonly used in landslide susceptibility models can lead to a misrepresentation of the distribution of negative samples,causing a deviation from actual geological conditions.This,in turn,negatively affects the discriminative ability and generalization performance of the models.To address this issue,we propose a novel approach for selecting negative samples to enhance the quality of machine learning models.We choose the Liangshan Yi Autonomous Prefecture,located in southwestern Sichuan,China,as the case study.This area,characterized by complex terrain,frequent tectonic activities,and steep slope erosion,experiences recurrent landslides,making it an ideal setting for validating our proposed method.We calculate the contribution values of environmental factors using the relief algorithm to construct the feature space,apply the Target Space Exteriorization Sampling(TSES)method to select negative samples,calculate landslide probability values by Random Forest(RF)modeling,and then create regional landslide susceptibility maps.We evaluate the performance of the RF model optimized by the Environmental Factor Selection-based TSES(EFSTSES)method using standard performance metrics.The results indicated that the model achieved an accuracy(ACC)of 0.962,precision(PRE)of 0.961,and an area under the curve(AUC)of 0.962.These findings demonstrate that the EFSTSES-based model effectively mitigates the negative sample imbalance issue,enhances the differentiation between landslide and non-landslide samples,and reduces misclassification,particularly in geologically complex areas.These improvements offer valuable insights for disaster prevention,land use planning,and risk mitigation strategies. 展开更多
关键词 Non-landslide sample selection relief algorithm Target Space Exteriorization Sampling Landslide Susceptibility Assessment
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Development of Oilfield Blockage Relief and Injection System Based on Bio-Based Surfactants
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作者 Wang Fei Chen Zhaoxian +2 位作者 Liu Gang Zhang Huili Hu Meijuan 《China Detergent & Cosmetics》 2025年第3期40-46,共7页
By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permea... By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permeability and heavy oil reservoirs under varying temperature conditions.The results demonstrate that this system effectively reduces oil–water interfacial tension,achieving an ultra-low interfacial tension state.The static oil washing efficiency of oil sands exceeds 85%,the average pressure reduction rate reaches 21.55%,and the oil recovery rate improves by 13.54%.These enhancements significantly increase the system’s ability to dissolve oilbased blockages,thereby lowering water injection pressure caused by organic fouling,increasing the injection volume of injection wells,and ultimately improving oil recovery efficiency. 展开更多
关键词 bio-based surfactants oil extraction technology pressure reduction and blockage relief
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Compound lidocaine cream with warm compress for pain relief in ultrasound-guided peripherally inserted central catheter placement for cancer patients
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作者 Yan Wang Xue-Ni Yang +4 位作者 Sheng Ji Yu-Mei Zhang Yi Wang Yan-Mei Wang Yue-Xia Gu 《World Journal of Clinical Oncology》 2025年第7期217-223,共7页
BACKGROUND Ultrasound-guided peripherally inserted central catheter(PICC)placement is vital for cancer therapy,but lidocaine infiltration faces limitations like puncture pain and vasospasm.AIM To assess the clinical e... BACKGROUND Ultrasound-guided peripherally inserted central catheter(PICC)placement is vital for cancer therapy,but lidocaine infiltration faces limitations like puncture pain and vasospasm.AIM To assess the clinical efficacy of a no-pain intervention-combining compound lidocaine cream with warm compress-in reducing pain during ultrasound-guided PICC placement in cancer patients.METHODS A retrospective cohort study analyzed 88 cancer patients undergoing PICC placement(Shanghai Fourth People’s Hospital,2024).Patients were divided into control(lidocaine infiltration,n=44)and intervention(cream+warm compress,n=44)groups.Primary outcomes:Pain scores(numerical rating scale),procedural time,complications;secondary outcome:Satisfaction.RESULTS The intervention group showed significantly lower pain scores(1.2±0.4 vs 3.8±1.2,P=0.012)with comparable first-attempt success(95.5%vs 90.9%)and safety(P=0.672).Thermal activation of transient receptor potential vanilloid 1 channel enhanced drug penetration,achieving anesthesia within 8-10 minutes.Patient satisfaction reached 97.7%.CONCLUSION The combination of compound lidocaine cream with warm compress significantly alleviates procedural pain and enhances patient satisfaction during ultrasound-guided PICC placement in cancer patients,supporting its clinical application. 展开更多
关键词 ULTRASOUND-GUIDED Peripherally inserted central catheter placement Pain relief Compound lidocaine cream Warm compress Retrospective study Cancer patients
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偶氮基薄膜的全息光存储
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作者 付申成 刘益春 《高等学校化学学报》 北大核心 2026年第1期35-41,共7页
全息光存储利用光的干涉和衍射原理记录并重建三维信息,具有超高存储密度和并行读写能力,是信息存储的重要发展方向.在诸多全息存储介质中,偶氮分子因其分子体积小、偏振敏感、光响应速度快、折射指数变化幅度大及与聚合物基质兼容性好... 全息光存储利用光的干涉和衍射原理记录并重建三维信息,具有超高存储密度和并行读写能力,是信息存储的重要发展方向.在诸多全息存储介质中,偶氮分子因其分子体积小、偏振敏感、光响应速度快、折射指数变化幅度大及与聚合物基质兼容性好等优势而备受关注.本文综合评述了40年来偶氮材料在偏振全息存储和表面浮雕光栅领域的发展情况,特别展示了偶氮分子掺杂的聚合物薄膜高密度复用偏振全息存储的设计思路和实验结果,分析了偶氮基薄膜用于光子集成芯片的可行性. 展开更多
关键词 偶氮分子 偏振全息 表面浮雕光栅
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基于Relief特征量优化及SOM网络的断路器操作机构状态评估 被引量:14
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作者 张浩 赵莉华 +5 位作者 景伟 阳薇 姜海洋 朱林林 荣强 付荣荣 《高压电器》 CAS CSCD 北大核心 2017年第9期240-246,共7页
为提高断路器操作机构状态评估的效率及准确性,文中提出了采用Relief优化方法对分合闸线圈电流特征向量进行优化及SOM网络对线圈电流样本进行分类的高压断路器操作机构状态评估方法。仿真研究结果表明:基于Relief的分合闸线圈电流特征... 为提高断路器操作机构状态评估的效率及准确性,文中提出了采用Relief优化方法对分合闸线圈电流特征向量进行优化及SOM网络对线圈电流样本进行分类的高压断路器操作机构状态评估方法。仿真研究结果表明:基于Relief的分合闸线圈电流特征向量优化方法和SOM网络分类方法的操作机构状态评估能够实现操作机构状态的准确评估,同时采用优化后的电流特征向量数据进行状态评估减小了运算量和缩短了运算时间,提高了断路器机构状态评估的效率。 展开更多
关键词 relief 状态评估 特征向量 操作机构 SOM
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基于GF-1遥感影像和relief-mRMR-GASVM模型的小麦白粉病监测 被引量:15
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作者 黄林生 阮超 +3 位作者 黄文江 师越 彭代亮 丁文娟 《农业工程学报》 EI CAS CSCD 北大核心 2018年第15期167-175,314,共10页
选择合适的建模和特征选择算法对提高作物病害的遥感监测水平有着重要的作用。研究以河北省小麦白粉病为研究对象,基于GF-1/WFV数据共提取了4个波段反射率数据和10个对作物长势和胁迫敏感的植被指数作为初选特征。针对常用的特征提取算... 选择合适的建模和特征选择算法对提高作物病害的遥感监测水平有着重要的作用。研究以河北省小麦白粉病为研究对象,基于GF-1/WFV数据共提取了4个波段反射率数据和10个对作物长势和胁迫敏感的植被指数作为初选特征。针对常用的特征提取算法relief算法筛选出的特征存在冗余性的问题,提出了一种relief结合最小冗余最大相关(minimum redundancy maximum relevance,m RMR)的特征降维算法(relief-m RMR)。首先,通过relief算法计算出各特征的权重系数,对特征集进行加权;然后利用m RMR算法选出与类别具有最小冗余性的特征,利用支持向量机(support vector machine,SVM)对河北白粉病进行监测,并用遗传算法(genetic algorithm,GA)优化的SVM(GASVM)建立了白粉病的监测模型(relief-m RMR-GASVM),将监测结果分别与SVM和网格寻优(grid search,GS)算法优化的SVM(GSSVM)的监测结果进行对比分析,同时比较了该方法与Ada Boost、粒子群(Pso)优化的最小二乘支持向量机(least squares support vector machine,Pso-LSSVM)和随机森林(random forest,RF)3种方法的优越性。结果表明,relief-m RMR算法筛选出的特征与GASVM、SVM和GSSVM建立的监测模型精度比传统relief算法筛选特征所建模型的精度分别提高了14.3个百分点、7.2个百分点和7.1个百分点,比传统m RMR算法筛选特征所建模型的精度分别提高了14.3个百分点、14.3个百分点和14.2个百分点。relief-m RMR算法结合GASVM建立的监测模型精度为所有模型中最高,精度为85.7个百分点,分别比SVM和GSSVM所建监测模型精度提高了21.4个百分点和7.2个百分点。此外,GF-1数据结合relief-m RMR-GASVM模型的监测精度分别高出Ada Boost、Pso-LSSVM和RF方法21.4个百分点、14.3个百分点和7.1个百分点。说明GF-1数据结合relief-m RMR-GASVM模型可用于小麦白粉病的遥感监测。 展开更多
关键词 病害 遥感 监测 小麦 白粉病 支持向量机 relief算法 mRMR算法
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不平衡数据集上的Relief特征选择算法 被引量:15
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作者 菅小艳 韩素青 崔彩霞 《数据采集与处理》 CSCD 北大核心 2016年第4期838-844,共7页
Relief算法为系列特征选择方法,包括最早提出的Relief算法和后来拓展的ReliefF算法,核心思想是对分类贡献大的特征赋予较大的权值;特点是算法简单,运行效率高,因此有着广泛的应用。但直接将Relief算法应用于有干扰的数据集或不平衡数据... Relief算法为系列特征选择方法,包括最早提出的Relief算法和后来拓展的ReliefF算法,核心思想是对分类贡献大的特征赋予较大的权值;特点是算法简单,运行效率高,因此有着广泛的应用。但直接将Relief算法应用于有干扰的数据集或不平衡数据集,效果并不理想。基于Relief算法,提出一种干扰数据特征选择算法,称为阈值-Relief算法,有效消除了干扰数据对分类结果的影响。结合K-means算法,提出两种不平衡数据集特征选择算法,分别称为K-means-ReliefF算法和K-means-Relief抽样算法,有效弥补了Relief算法在不平衡数据集上表现出的不足。实验证明了本文算法的有效性。 展开更多
关键词 特征选择 relief算法 reliefF算法 不平衡数据集
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基于Q-relief的图像特征选择算法 被引量:8
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作者 范文兵 王全全 +1 位作者 雷天友 朱辉 《计算机应用》 CSCD 北大核心 2011年第3期724-728,共5页
针对特征选择算法——relief在训练个别属性权值时的盲目性缺点,提出了一种基于自适应划分实例集的新算法——Q-relief,该算法改正了原算法属性选择时的盲目性缺点,选择出表达图像信息最优的特征子集来进行模式识别。将该算法应用于列... 针对特征选择算法——relief在训练个别属性权值时的盲目性缺点,提出了一种基于自适应划分实例集的新算法——Q-relief,该算法改正了原算法属性选择时的盲目性缺点,选择出表达图像信息最优的特征子集来进行模式识别。将该算法应用于列车运行故障动态图像监测系统(TFDS)的故障识别,经实验验证,与其他算法相比,Q-relief算法明显提高了故障图像识别的准确率。 展开更多
关键词 特征选择 relief算法 纹理特征 模式识别
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极大熵Relief特征加权 被引量:9
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作者 张翔 邓赵红 +1 位作者 王士同 蔡及时 《计算机研究与发展》 EI CSCD 北大核心 2011年第6期1038-1048,共11页
Relief特征加权的最新研究进展表明其可近似地表述为一个间距最大化优化问题.尽管该类算法广为应用,但仍然存在一些缺陷.为了提高Relief特征加权的适应性和鲁棒性,融合间距最大化和极大熵理论,并由此探讨了新的鲁棒的具有更好适应性的Re... Relief特征加权的最新研究进展表明其可近似地表述为一个间距最大化优化问题.尽管该类算法广为应用,但仍然存在一些缺陷.为了提高Relief特征加权的适应性和鲁棒性,融合间距最大化和极大熵理论,并由此探讨了新的鲁棒的具有更好适应性的Relief特征加新方法.首先,构造了一个结合极大熵原理的间距最大化目标函数.对于该目标函数,运用优化理论得到一些重要的理论结果.在此基础上,对于两类数据、多类数据和在线数据,提出了一组鲁棒的Relief特征加权算法.利用UCI基准数据集和基因数据集进行了实验验证,结果表明提出的新Relief特征加权算法对噪音和例外点显示出了更好的适应性和鲁棒性. 展开更多
关键词 relief算法 特征选择 特征加权 间距最大化原则 极大熵
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基于Relief相关性特征提取和微分进化支持向量机的短期电价预测 被引量:11
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作者 彭春华 刘刚 相龙阳 《电工技术学报》 EI CSCD 北大核心 2013年第1期277-284,共8页
针对电价预测中特征输入量选择的盲目性,本文通过改进传统的Relief算法,提出一种电价预测输入量的自动选取方法,并引入相关性分析来剔除冗余特征。在此基础上,采用支持向量机来建立电价预测模型并应用微分进化算法来优化选择支持向量机... 针对电价预测中特征输入量选择的盲目性,本文通过改进传统的Relief算法,提出一种电价预测输入量的自动选取方法,并引入相关性分析来剔除冗余特征。在此基础上,采用支持向量机来建立电价预测模型并应用微分进化算法来优化选择支持向量机的参数以达到提高预测精度的目的。以PJM电力市场的真实电价来进行仿真分析,结果表明本文的特征选取方法能够很好地提取电价的短期趋势特征和周期性特征,而微分进化优化的支持向量机也获得了比常规支持向量机和BP神经网络要好的预测结果,体现了本文方法的优越性。 展开更多
关键词 电价预测 relief算法 相关性分析 微分进化算法 支持向量机
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基于组合赋权法和响应面法的巷道围岩钻孔卸压参数优化研究
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作者 陈晓祥 任俊龙 《河南理工大学学报(自然科学版)》 北大核心 2026年第1期60-69,142,共11页
目的 为了解决巷道围岩严重变形问题,基于组合赋权法和响应面法对巷道围岩钻孔卸压参数进行优化研究。方法 针对李村煤矿巷道两帮围岩钻孔卸压参数优选问题,结合现场实际工程地质条件,采用Box-Behnken方法设计25组试验方案。应用FLAC3D... 目的 为了解决巷道围岩严重变形问题,基于组合赋权法和响应面法对巷道围岩钻孔卸压参数进行优化研究。方法 针对李村煤矿巷道两帮围岩钻孔卸压参数优选问题,结合现场实际工程地质条件,采用Box-Behnken方法设计25组试验方案。应用FLAC3D进行数值模拟分析,获得不同参数条件下的力学响应特征,结合技术经济要求,选取施工成本、两帮移近量、顶底板移近量、最大垂直应力、塑性区面积、施工效率等6个指标,利用层次分析法和主成分分析法组合赋权各评价指标。结果 提出巷道围岩钻孔卸压参数综合评价模型,克服评价指标单一、主观因素干扰等缺陷,形成系统、准确的评价方法。以规范化综合评分为响应指标、钻孔卸压参数为变量,构建多元二阶回归预测方程。巷道围岩钻孔卸压优化参数为:孔径0.1 m,孔深4 m,间排距1 m×1 m,此时综合效益最佳。结论 提出的回归预测模型选取的钻孔卸压参数合理可行,降低围岩变形量的同时保证了经济效益,可为相关巷道围岩控制方案设计提供借鉴。 展开更多
关键词 钻孔卸压 响应面法 参数优化 主成分分析法 层次分析法
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