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| 1 | Prevention and treatment technologies of railway tunnel water inrush and mud gushing in China显示文摘Water inrush and mud gushing are one of the biggest hazards in tunnel construction. Unfavorable geological sections can be observed in almost all railway tunnels under construction or to be constructed, and vary in extent. Furthermore, due to the different heights of mountains and the lengths of tunnels, the locations of the unfavorable geological sections cannot be fully determined before construction, which increases the risk of water inrush and mud gushing. Based on numerous cases of water inrush and mud gushing in railway tunnels, the paper tries to classify water inrush and mud gushing in railway tunnels in view of the conditions of the surrounding rocks and meteorological factors associated with tunnel excavation. In addition, the causes of water inrush and mud gushing in combination of macroand micromechanisms are summarized, and site-specifc treatment method is put forward. The treatment methods include choosing a method of advance geological forecast according to risk degrees of different sections in the tunnel, determining the items of predictions, and choosing the appropriate methods, i.e. draining-oriented method, blocking-oriented method or draining-and-blocking method. The treatment technologies of railway water inrush and mud gushing are also summarized, including energy relief and pressure relief technology, advance grouting technology, and advance jet grouting technology associated with their key technical features and applicable conditions. The results in terms of treatment methods can provide reference to the prevention and treatment of tunnel water inrush and mud gushing. | Yong Zhao Pengfei Li Siming Tian | 2013 | Journal of Rock Mechanics and Geotechnical Engineering2013，5，6： | 16 |
| 2 | 基于Relief特征量优化及SOM网络的断路器操作机构状态评估显示文摘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。 | 张浩 赵莉华 景伟 阳薇 姜海洋 朱林林 荣强 付荣荣 | 2017 | 高压电器2017，53，9： | 13 |
| 3 | Guiding-controlling technology of coal seam hydraulic fracturing fractures extension显示文摘Aiming at the uncontrollable problem of extension direction of coal seam hydraulic fracturing,this study analyzed the course of fractures variation around the boreholes in process of hydraulic fracturing,and carried out the numerical simulations to investigate the effect of artificial predetermined fractures on stress distribution around fractured holes.The simulation results show that partial coal mass occurs relatively strong shear failure and forms weak surfaces,and then fractures extended along the desired direction while predetermined fractures changed stress distribution.Directional fracturing makes the fractures link up and the pressure on coal mass is relieved within fractured regions.Combining deep hole controlling blasting with hydraulic fracturing was proposed to realize the extension guiding-controlling technology of coal seam fractures.Industrial experiments prove that this technology can avoid local stress concentration and dramatically widen the pressure relief scope of deep hole controlling blasting.The permeability of fractured coal seam increased significantly,and gas extraction was greatly improved.Besides,regional pressure relief and permeability increase was achieved in this study. | Zhai Cheng Li Min Sun Chen Zhang Jianguo Yang Wei Li Quangui | 2012 | International Journal of Mining Science and Technology2012，22，6： | 12 |
| 4 | 基于特征加权融合的鱼类摄食活动强度评估方法显示文摘为解决鱼类养殖中投喂精度低的问题,提出了一种基于特征加权融合的鱼类摄食活动强度评估方法。该方法以鱼群为研究对象,利用不同摄食阶段图像的特征对摄食活动强度进行分析,避免了复杂背景中单体鱼的切割。首先,利用图像预处理技术获取前景目标,通过鱼群质心绘制出不同摄食阶段的鱼群游动轨迹;其次,分别提取图像的颜色、形状和纹理等特征;然后,使用Relief特征选择和XGBoost算法筛选出3个摄食评价因子,采用加权融合方法确定每个评价因子的最佳权重;最后,通过融合后的特征对摄食活动强度进行评估。试验结果表明,与传统面积法相比,本文提出方法的决定系数可达0.9043,且摄食识别准确率高达98.89%。该方法在增强鲁棒性的同时,提高了检测和评估效率,可为鱼群摄食行为检测和活动强度评估提供参考。 | 陈明 张重阳 冯国富 陈希 陈冠奇 王丹 | 2020 | 农业机械学报2020，51，2： | 12 |
| 5 | 一种基于标签相关度的Relief特征选择算法显示文摘特征选择在机器学习和数据挖掘中起到了至关重要的作用。Relief作为一种高效的过滤式特征选择算法,能处理多种类型的数据,且对噪声的容忍力较强,因此被广泛应用。然而,经典的Relief算法对离散特征的评价较为简单,在实际进行特征选择时并未充分挖掘特征与类标签之间的潜在关系,具有很大的改进空间。针对经典的Relief算法对离散特征的评价方式较为简单这一不足,提出了一种基于标签相关度的离散特征评价方法。该算法充分考虑了不同特征的特性,给出了一种面向混合特征的距离度量方式,同时从离散特征与标签之间的相关度出发,重新定义了Relief算法对离散特征的评价体系。实验结果表明,改进后的Relief算法与经典的Relief算法和现有的一些面向混合数据的特征选择算法相比,其分类精度均有不同程度的提升,具有良好的性能。 | 丁思凡 王锋 魏巍 | 2021 | 计算机科学2021，48，4： | 11 |
| 6 | 基于邻域粗糙集和Relief的弱标记特征选择方法显示文摘在多标记学习与分类中,现有邻域粗糙集特征选择算法若将样本的分类间隔作为邻域半径,则会出现分类间隔过大导致分类无意义、样本距离过大容易造成异类样本和同类样本失效,以及无法处理弱标记数据等情况。为解决这些问题,提出一种基于多标记邻域粗糙集和多标记Relief的弱标记特征选择方法。首先,引入异类样本数和同类样本数来改进分类间隔,在此基础上定义邻域半径,构造新的邻域近似精度与多标记邻域粗糙集模型,并有效度量边界域引起的集合不确定性。其次,利用迭代更新权重公式填补大部分缺失标记信息,将邻域近似精度与互信息相结合,以构造新的标记相关性,填补剩余的缺失标记信息。然后,使用异类样本数和同类样本数,以构造新的标记权重和特征权重计算公式,进而提出多标记Relief模型,并将其应用于多标记特征选择。最后,结合多标记邻域粗糙集模型和多标记Relief算法,设计一种新的弱标记特征选择算法,以处理带有缺失标记的高维数据,并有效地提升多标记分类性能。在11个公共多标记数据集上进行仿真实验,结果验证了所提出的弱标记特征选择算法的有效性。 | 孙林 黄苗苗 徐久成 | 2022 | 计算机科学2022，49，4： | 11 |
| 7 | 基于ReliefF-PCA和SVM的发动机故障诊断方法研究显示文摘针对柴油发动机机组振动信号非线性和非平稳性以及机组实际故障案例样本数据少的特点,提出了一种基于Relief F、主成分分析(PCA)以及支持向量机(SVM)的柴油发动机故障诊断方法。首先提取发动机冲击信号的特征参数,运用Relief F选择出其中的敏感特征以降低处理过程的计算难度;然后采用PCA进一步提取敏感特征,消除各特征之间的相关性,避免冗余;最后利用SVM实现机组的故障分类,诊断不同类型的故障。将本文方法应用于柴油机实际典型故障案例中,结果表明该方法能有效提取柴油机缸盖振动信号中的故障敏感特征,并实现多种典型故障的诊断。 | 朱丽娜 王学杰 张进杰 | 2018 | 北京化工大学学报(自然科学版)2018，45，1： | 10 |
| 8 | An improved analytical model of cutting temperature in orthogonal cutting of Ti6Al4V显示文摘Cutting heat has significant effects on the machined surface integrity of titanium alloys in the aerospace field. Many unwanted problems such as surface burning, work hardening, and tool wear can be induced by high cutting temperatures. Therefore, it is necessary to accurately predict the cutting temperature of titanium alloys. In this paper, an improved analytical model of the cutting temperature in orthogonal cutting of titanium alloys is proposed based on the Komanduri-Hou model and the Huang-Liang model. The temperatures at points in a cutting tool, chip, and workpiece are calculated by using the moving heat source method. The tool relief angle is introduced into the proposed model, and imaginary mirrored heat sources of the shear plane heat source and the frictional heat source are applied to calculate the temperature rise in a semi-infinite medium. The heat partition ratio along the tool-chip interface is determined by the discretization method. For validation purpose, orthogonal cutting of titanium alloy Ti6Al4V is performed on a lathe by using a sharp tool. Experimental results show to be consistent well with those of the proposed model,yielding a relative difference of predicted temperature from 0.49% to 9.00%. The model demonstrates its ability of predicting cutting temperature in orthogonal cutting of Ti6Al4V. | Chenwei SHAN Xu ZHANG Bin SHEN Dinghua ZHANG | 2019 | Chinese Journal of Aeronautics2019，32，3： | 10 |
| 9 | 基于KSLPP与RWKNN的旋转机械故障诊断显示文摘针对旋转机械高维故障特征集识别精度低的问题,提出基于核监督局部保留投影(Kernel Supervised Locality Preserving Projection,KSLPP)与Relief F特征加权的K近邻(Relief F Weighted K-Nearest Neighbor,RWKNN)分类器相结合的维数约简故障诊断方法。该方法首先应用KSLPP提取故障特征集中的非线性信息,同时在降维投影过程中充分利用类别信息,使降维后最小化类内散度,最大化类间分离度;随后,将降维后得到的低维敏感特征集输入RWKNN进行模式识别,RWKNN能够突出不同特征对分类的贡献率,强化敏感特征,弱化不相关特征,提升了分类精度和鲁棒性。最后,通过典型转子实验台的故障特征集验证了该方法的有效性。 | 王雪冬 赵荣珍 邓林峰 | 2016 | 振动与冲击2016，35，8： | 10 |
| 10 | 基于特征选择和XGBoost的风机叶片结冰预测显示文摘风电场风机叶片积冰会造成风电机组的效率降低,严重时会导致叶片断裂,严重威胁风电场的正常生产运行。提出了一种基于Relief的特征选择和XGBoost的风机叶片结冰预测方法,能够根据风机运行的SCADA数据对叶片结冰的早期过程进行精确预测,并采用某风电场的2台风机数据进行模型验证和对比试验,取得了较好的预测精度,提升了预测速度,能够有效预测早期叶片结冰故障的发生,从而为降低风机的效率损失和风机的运行风险提供数据支撑。 | 曹渝昆 朱萌 王晓飞 | 2019 | 电气自动化2019，41，3： | 8 |
| 11 | OBIA与RF结合的龙口市土地利用信息提取方法显示文摘为提高中分辨率遥感影像解译精度,本文提出面向对象影像分析(Object Based Image Analysis,OBIA)与随机森林(Random Forest,RF)结合的土地利用信息提取方法。采用Landsat8 OLI影像,针对不同地物特点,阈值分割和多尺度分割结合创建影像对象,规则集和分类器协同分类,基于Relief F算法分别对光谱特征、纹理特征及所有特征降维筛选特征子集,并与全部特征一起应用RF建模,对龙口市进行土地利用信息提取与比较。结果表明:OBIA与RF结合提取土地利用信息,基于Relief F算法筛选纹理特征,保留完整光谱、几何、空间关系特征构建RF模型,建模错分率为0.0958,分类总体精度和Kappa系数分别为89.37%和0.872,取得较理想结果。该方法可应用于中分辨率遥感影像土地利用信息提取。 | 王瑷玲 张校千 苏晨晨 于新洋 | 2019 | 自然资源学报2019，34，4： | 8 |
| 12 | Topographical relief characteristics and its impact on population and economy:A case study of the mountainous area in western Henan,China显示文摘Topographical relief is a key factor that limits population distribution and economic development in mountainous areas.The limitation is especially apparent in the mountain?plain t「ansition zone.Taking the transition zone between the Qinling Mountains and the North China Plain(i.e.the mountainous area in western Henan Province)as an example and based on the 200-m resolution DEM data,we used the mean change-point analysis to determine the optimal statistical unit for topographical relief,and thereafter extracted the relief degree.Taking the 1:100,000 land use data,township population and county-level industrial data,population and economic spatial models were constructed,and 200?m resolution grid population and economic density maps were gen erated.Afterwards,statistical analysis was carried out to quantitatively reveal the impact of topographical relief on population and economy.In addition,the impacts of other topographical factors were discussed.The results showed the following.(1)The relief degree in western Henan is generally low,where 58.6%of the regional topography does not exceed half the height of a reference mountain(relative elevation W250 m).Spatially,the relief degree is high in the west while low in the east,and high in the middle while low in the north and south.There is a positive correlation between relief degree and elevation,and a much stronger correlation between relief degree and slope.(2)The linear fitting degree between the population and economic validation data and the corresponding simulation data are 0.943 and 0.909,respectively,indicating that the spatialized results can reflect the actual population and economic distribution.(3)The impact of topographical relief on population and economy was stronger than that of other topographical factors.The relief degree showed a good logarithmic fit relati on ship with population density(0.911)and economic density(0.874).Specifically,88.65%of the population lives in areas where the topographical relief is W0.5 and 88.03%of the gross regional product was from areas where the relief is W0.3.Compared with the population distribution,the economic development showed an obvious agglomeration trend towards low relief areas. | ZHANG Jingjing ZHU Wenbo ZHU Lianqi CUI Yaoping HE Shasha REN Han | 2019 | Journal of Geographical Sciences2019，29，4： | 8 |
| 13 | 扩展ReliefF的两种多标签特征选择算法显示文摘针对Relief F算法局限于单标签数据问题,提出两种多标签特征选择算法Mult-Relief F和M-A算法。Mult-Relief F算法重新定义了类内最近邻和类外最近邻的查找方法,并加入标签的贡献值更新特征权重公式。MA算法在Mult-Relief F算法的基础下,利用邻域能去除冗余的特性,更多地去除冗余特征达到更好的降维效果。采用ML-KNN分类算法进行实验。在多个数据集上测试表明,Mult-Relief F算法能提高分类效果,M-A算法能获得最小的特征子集。 | 马晶莹 宣恒农 | 2017 | 计算机应用与软件2017，34，7： | 8 |
| 14 | 基于模糊聚类的城市快速路交通流状态划分显示文摘针对城市快速路交通流状态分类的问题,提出了一种改进的模糊C均值(FCM)算法。结合层次聚类算法和FCM聚类算法,运用层次聚类算法得到最佳聚类数和初始聚类中心,并通过Relief F特征加权对影响交通状态的不同特征指标赋予相应的权值,最终用FCM算法再次聚类得出交通流状态的分类结果。以VISSIM为工具,对该方法进行了模拟。对比分析结果显示,所提出的方法能够提高城市快速路交通流状态分类的效果。 | 殷俊杰 丁宏飞 薄雾 钟媚 | 2013 | 重庆交通大学学报(自然科学版)2013，32，4： | 8 |
| 15 | Proton pump inhibitor for non-erosive reflux disease:A meta-analysis显示文摘AIM:To evaluate the efficacy,safety and influential factors of proton pump inhibitor(PPI)treatment for non-erosive reflux disease(NERD).METHODS:PubMed,MEDLINE,EMBASE and the Cochrane Library were searched up to April 2013 to identify eligible randomized controlled trials(RCTs)that probed into the efficacy,safety and influential factors of PPI treatment for NERD.The rates of symptomatic relief and adverse events were measured as the outcomes.After RCT selection,assessment and data collection,the pooled RRs and 95%CI were calculated.This meta-analysis was performed using the Stata 12.0 software(Stata Corporation,College Station,Texas,United States).The level of evidence was estimated by the Grading of Recommendations Assessment,Development and Evaluation system.RESULTS:Seventeen RCTs including 6072 patients met the inclusion criteria.The results of the metaanalysis showed that PPI treatment was significantly superior to H2receptor antagonists(H2RA)treatment(RR=1.629,95%CI:1.422-1.867,P=0.000)and placebo(RR=1.903,95%CI:1.573-2.302,P=0.000)for the symptomatic relief of NERD.However,there were no obvious differences between PPI and H2RA(RR=0.928,95%CI:0.776-1.110,P=0.414)or PPI and the placebo(RR=1.000,95%CI:0.896-1.116,P=0.997)regarding the rate of adverse events.The overall rate of symptomatic relief of PPI against NERD was 51.4%(95%CI:0.433-0.595,P=0.000),and relief was influenced by hiatal hernia(P=0.030).The adverse rate of PPI against NERD was 21.0%(95%CI:0.152-0.208,P=0.000),and was affected by hiatal hernia(P=0.081)and drinking(P=0.053).CONCLUSION:PPI overmatched H2RA on symptomatic relief rate but not on adverse rate for NERD.Its relief rate and adverse rate were influenced by hiatal hernia and drinking. | Ji-Xiang Zhang Meng-Yao Ji Jia Song Hong-Bo Lei Shi Qiu Jing Wang Ming-Hua Ai Jun Wang Xiao-Guang Lv Zi-Rong Yang Wei-Guo Dong | 2013 | World Journal of Gastroenterology2013，19，45： | 8 |
| 16 | Biofilm Microenvironment-Responsive Nanotheranostics for Dual-Mode Imaging and Hypoxia-Relief-Enhanced Photodynamic Therapy of Bacterial Infections显示文摘The formation of bacterial biofilms closely associates with infectious diseases.Until now,precise diagnosis and effective treatment of bacterial biofilm infections are still in great need.Herein,a novel multifunctional theranostic nanoplatform based on MnO_(2)nanosheets(MnO_(2)NSs)has been designed to achieve pH-responsive dual-mode imaging and hypoxia-relief-enhanced antimicrobial photodynamic therapy(aPDT)of bacterial biofilm infections.In this study,MnO_(2)NSs were modified with bovine serum albumin(BSA)and polyethylene glycol(PEG)and then loaded with chlorin e_(6)(Ce_(6))as photosensitizer to form MnO_(2)-BSA/PEG-Ce_(6)nanosheets(MBP-Ce_(6)NSs).After being delivered into the bacterial biofilm-infected tissues,the MBP-Ce_(6)NSs could be decomposed in acidic biofilm microenvironment and release Ce_(6)with Mn^(2+),which subsequently activate both fluorescence(FL)and magnetic resonance(MR)signals for effective dual-mode FL/MR imaging of bacterial biofilm infections.Meanwhile,MnO_(2)could catalyze the decomposing of H2O_(2)in biofilm-infected tissues into O_(2)and relieve the hypoxic condition of biofilm,which significantly enhances the efficacy of aPDT.An in vitro study showed that MBP-Ce_(6)NSs could significantly reduce the number of methicillin-resistant Staphylococcus aureus(MRSA)in biofilms after 635nm laser irradiation.Guided by FL/MR imaging,MRSA biofilm-infected mice can be efficiently treated by MBP-Ce_(6)NSs-based aPDT.Overall,MBP-Ce_(6)NSs not only possess biofilm microenvironment-responsive dual-mode FL/MR imaging ability but also have significantly enhanced aPDT efficacy by relieving the hypoxia habitat of biofilm,which provides a promising theranostic nanoplatform for bacterial biofilm infections. | Weijun Xiu Siyu Gan Qirui Wen Qiu Qiu Sulai Dai Heng Dong Qiang Li Lihui Yuwen Lixing Weng Zhaogang Teng Yongbin Mou Lianhui Wang | 2020 | Research2020，，1： | 7 |
| 17 | Induced drill-spray during hydraulic slotting of a coal seam and its influence on gas extraction显示文摘Hydraulic slotting can induce drill spray in a gassy,low permeability coal seam.This then influences subsequent gas extraction.This paper describes the drill spray phenomenon from a mechanical perspective and analyzes the effects of water jet damage during slotting.A simulation of the stresses around the drill hole and slot was prepared using FLAC-3D code.It helps explain the induction of drill spray during hydraulic slotting.The stress concentration around the bore increases as the diameter of the hole increases.As the hole enlarges the variation in stress also increases,which introduces an instability into the coal.This allows easy breaking and removal of the coal.Destruction of the coal structure by the water jet is the major factor causing drill spray.Energy stored as either strain or gas pressure is released by the water jet and this causes the coal to fracture and be expelled from the hole.Field tests showed the effect on gas extraction after slotting with drill spray.The concentration of gas increases after drilling.Compared to conventional techniques,the hydraulic slotted bore gives a gas concentration three times higher and has an effective range twice as far.This makes the gas extraction process more efficient and allows reduced construction effort. | Shen Chunming Lin Baiquan Zhang Qizhi Yang Wei Zhang Lianjun | 2012 | International Journal of Mining Science and Technology2012，22，6： | 7 |
| 18 | 文档分类之特征选择方法的实验比较显示文摘在自动化信息处理中,由于大量信息是基于文字表达的,使得文本分类成为其核心任务之一。其中,相比较其他分类算法,基于类中心的文档分类方法凭借其极高的效率和较好的性能得到了更广泛的应用。然而,该分类方法的性能很大程度上取决于文本的特征空间表示。在此将4种较大差异的特征选择方法作为预处理方法,构造适合类中心点分类的特征空间,对它们的性能进行分析。实验表明,基于支持向量机的特征选择方法不仅有较好的最低错误率,并且对选择的特征数目不敏感,因此我们推荐在实际应用中使用基于支持向量机的特征选择方法作为基于类中心的文档分类算法的预处理。 | 张建兵 戴新宇 陈家骏 | 2008 | 广西师范大学学报(自然科学版)2008，26，3： | 6 |
| 19 | 基于Relief特征选择算法与多生理信号的焦虑状态识别显示文摘焦虑是一种在感到被威胁的环境中产生的复杂的心理过程。该文通过任务驱动的焦虑情绪诱发实验,采集被试心电、呼吸、血容量搏动、皮肤电四种生理信号数据,结合Relief算法对特征进行选择,并结合k近邻算法(kNN)和支持向量机(SVM)算法,对平静状态和焦虑情绪状态进行识别分类。结果表明,对于焦虑情绪状态下的情绪识别,Relief-SVM算法优于Relief-kNN算法;利用多生理参数进行情绪识别优于单一生理参数。 | 雷沛 王静 周昕炜 柴新禹 | 2014 | 中国医疗器械杂志2014，38，3： | 5 |
| 20 | AFM quantitative analysis and determination of shear angle of {259}_f martensitic surface relief显示文摘An attentive observation and quantitative analysis of {259}f martensitic surface relief in an Fe-23Ni-0.55C alloy are made by means of an atomic force microscope (AFM), and different martensitic variants' shear angles are determined in this paper. The experiments show that {259}f martensitic surface relief exhibits regular shape in many cases, which is in agreement with the prediction of invariant plane strain (IPS). Generally, {259}f martensitic surface relief appears to be 'N'-shaped, but it is tent-shaped in the case of zigzag-shaped martensite. The compressed deformation of parent phase diminishes the surface relief in size but with little change of its relief angle. {259}f martensitic surface relief, large or small, has approximately the same relief angles, exhibiting a good 'self-similar fractal'. The determined values of different {259}f martensitic variants' shear angles are in fine agreement with the prediction of Wechsler-Liberman-Read (W-L-R) theory, with only a slight difference of less than 3.65°. | LIN Xiaoping, GU Nanju, ZHANG Yong, MENG Zhaowei and MA Xiaoli(Department of Materials Science and Technology, Hebei University of Technology, Tianjin 300130, China) | 2002 | Progress in Natural Science:Materials International2002，12，10： | 5 |
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