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基于光谱指数法的本溪市域红叶提取方法研究

测绘与空间地理信息 2022年第4期45卷 47-50页

作者：李炜浩张硕刘梓航苏旻高浩然刘善军东北大学资源与土木工程学院辽宁沈阳110819

红叶是一类观赏树木的统称,有槭树红叶、黄栌红叶、火炬树红叶等种类,在全国皆有分布。本溪是中国枫叶之都,快速、准确地提取其红叶信息能够促进当地旅游业的发展,具有巨大的经济价值与发展前景。然而传统的红叶指数播报采用人工定点观... 详细信息

红叶是一类观赏树木的统称,有槭树红叶、黄栌红叶、火炬树红叶等种类,在全国皆有分布。本溪是中国枫叶之都,快速、准确地提取其红叶信息能够促进当地旅游业的发展,具有巨大的经济价值与发展前景。然而传统的红叶指数播报采用人工定点观测的形式,耗费人力物力且无法实现大范围的红叶面积提取,为此,本研究采用光谱指数法快速、准确地提取红叶面积,选择本溪老边沟、天桥沟为中心的区域。首先利用目视解译法确定Sentinel-2影像上红叶像元区域,分析红叶和非红叶植被的光谱差异,并基于可见光波段的光谱特征构建差值红叶指数DRI,用于提取红叶区域,结果显示DRI的提取精度可达92%,与其他方法对比效果良好。本研究为本溪地区红叶面积提取提供了一种便利、高效的方法。

关键词：光谱指数法红叶 Sentinel-2

FT-ICR mass spectrometry for molecular characterization of water-insoluble organic compounds in winter atmospheric fine particulate matters

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Journal of Environmental Sciences 2022年第1期34卷 51-60页

作者： Cuiping Ning Yuan gao haoran Yu Haijun Zhang Ningbo Geng Rong Cao Jiping Chen CAS Key Laboratory of Separation Sciences for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China University of Chinese Academy of Sciences Beijing 100049China

Water-insoluble organic compounds(WIOCs)are an important fraction of atmospheric fine particulate matters(PM_(2.5)),which could affect the climate system and threaten human health *** this study,molecular characterization of WIOCs in PM_(2.5) were investigated by 15 T Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)with atmospheric pressure photoionization(APPI)source in positive ion mode.A total of 2573 and1875 molecular formulas were identified in WIOCs extracted by dichloromethane,which were collected in hazy and normal days,*** identified molecular formulas were further classified into four major subgroups,including CH,CHN,CHO and CHNO *** compounds predominated in WIOCs,accounting for more than 60%in both *** compounds(26.6%)and CH compounds(16.1%)were the second highest subgroups in WIOCs from the hazy days and normal days,*** relative abundance and number of nitro-substituted aromatic compounds were significantly higher in hazy days than in normal *** molecular composition of WIOCs was more complex in hazy days while more aromatic compounds were identified in normal days.

关键词： PM_(2.5) WIOCs FT-ICR MS Molecular characteristics Polycyclic aromatic hydrocarbon

Correlation between antioxidant depletion kinetic model and ageing behaviour of cross-linked polyethylene cable insulation

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High Voltage 2023年第2期8卷 231-238页

作者： Yingying Zheng Yiwei Long Delun Yi haoran Zhang Jian gao Kangning Wu Jianying Li State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anShaanxiChina

A concise kinetic model catering for the antioxidant reaction of thermally aged crosslinked polyethylene(XLPE)cable insulation before its abrupt performance deterioration is proposed for life prediction and condition *** alternating current breakdown strength,elongation at break,carbonyl index,and pyrolysis activation energy of XLPE insulation are found to consistently display an abrupt change at a certain point of ageing *** is strongly correlated to the depletion of the antioxidant whose content gradually decreases with ageing time and drops to a critical value,after which the abrupt degradation of the above macroscopic performances *** on the simplified chain reactions of XLPE during thermal-oxidative ageing,a concise kinetic model about antioxidant prediction is accordingly established by solving the chemical kinetics *** indicates that the antioxidant content decays with the reciprocal of time before the abrupt degradation *** of antioxidant content predicted by the kinetic model at different temperatures matches well with the experimental results,and its reliability can also be proved by the Arrhenius relationship of the obtained *** kinetic model proposed herein demonstrates satisfying conciseness and thus can be highly feasible in ageing condition assessment and life predicting of XLPE insulation.

关键词： kinetic insulation depletion

Adaptive Scheme for Crowd Counting Using off-the-Shelf Wireless Routers

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Computer Systems Science & Engineering 2022年第4期41卷 255-269页

作者： Wei Zhuang Yixian Shen Chunming gao Lu Li haoran Sang Fei Qian School of Computer and Software Nanjing University of Information Science&TechnologyNanjing210044China Engineering Research Center of Digital Forensics Ministry of EducationNanjing University of Information Science and TechnologyNanjing210044China School of Engineering&Technology University of WashingtonTacomaWA 98402USA China General Nuclear Power Group Nanjing210028China Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing210029China

Since the outbreak of the world-wide novel coronavirus pandemic,crowd counting in public areas,such as in shopping centers and in commercial streets,has gained popularity among public health administrations for preventing the crowds from *** this paper,we propose a novel adaptive method for crowd counting based on Wi-Fi channel state information(CSI)by using common commercial wireless *** with previous researches on device-free crowd counting,our proposed method is more adaptive to the change of environ-ment and can achieve high accuracy of crowd count *** the dis-tance between access point(AP)and monitor point(MP)is typically non-ﬁxed in real-world applications,the strength of received signals varies and makes the tra-ditional amplitude-related models to perform poorly in different *** order to achieve adaptivity of the crowd count estimation model,we used convo-lutional neural network(ConvNet)to extract features from correlation coefﬁcient matrix of subcarriers which are insensitive to the change of received signal *** conducted experiments in university classroom settings and our model achieved an overall accuracy of 97.79%in estimating a variable number of participants.

关键词： CSI device-free deep learning crowd counting Wi-Fi wireless sensing

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试析测控技术与仪器的智能化发展与应用

今日自动化 2019年第3期 54-55页

作者：高浩然河北工业大学天津300000

文章主要对测控技术以及仪器智能化进行了简单阐述,并分析了测控技术以及仪器智能化的应用优势和发展趋势。

关键词：测控技术仪器智能化发展应用

对照CT增强扫描探讨扩散张量成像对疑似慢性肾盂肾炎的诊断价值

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医学影像学杂志 2016年第7期26卷 1250-1254页

作者：彭君杨茂生杨连军高浩然李海燕北京中医医院顺义医院北京101300

目的探讨以多层螺旋CT(MSCT)增强扫描为参考标准,分析慢性肾盂肾炎患者肾脏皮、髓质ADC值和FA值改变,评估扩散张量成像(DTI)在慢性肾盂肾炎诊断中的价值。方法临床高度疑诊慢性肾盂肾炎患者44例1周内分别接受MDCT增强扫描和DTI扫描,根... 详细信息

目的探讨以多层螺旋CT(MSCT)增强扫描为参考标准,分析慢性肾盂肾炎患者肾脏皮、髓质ADC值和FA值改变,评估扩散张量成像(DTI)在慢性肾盂肾炎诊断中的价值。方法临床高度疑诊慢性肾盂肾炎患者44例1周内分别接受MDCT增强扫描和DTI扫描,根据所订标准将肾脏MSCT增强扫描结果评定为正常或者异常,即分为CT阳性组和CT阴性组。随机选取20名健康志愿者作为对照组进行DTI扫描。结果 44例疑诊慢性肾盂肾炎患者经MSCT增强检查CT阳性组26例,CT阴性组18例。44例疑诊患者皮、髓质ADC值和FA值均出现了不同程度降低。三组间比较皮、髓质ADC值均无统计学差异(P>0.05),三组间比较皮质FA值差异有统计学意义(P0.05),CT阴性组与阳性组间比较差异有统计学意义(P>0.05)。结论慢性肾盂肾炎的DTI研究中髓质FA值较ADC值敏感,髓质FA值降低能一定程度的反映慢性肾炎肾炎的病理情况和功能变化。

关键词：慢性肾盂肾炎磁共振成像扩散张量成像体层摄影术,X线计算机

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一种空气污染物浓度预测深度学习平台

上海师范大学学报（自然科学版） 2020年第1期49卷 102-108页

作者：卢淑怡张波张旱文俞豪高浩然刘波上海师范大学信息与机电工程学院上海201418 上海超算科技有限公司上海201203

在空气污染大数据预处理的基础上,提出了一个基于深度学习的空气污染物浓度预测平台.该平台架构分为数据采集层、模型层和可视化界面层3个层次,分别实现了数据采集与处理,基于长短期记忆(LSTM)网络模型的污染物浓度预测,以及预测结果可... 详细信息

在空气污染大数据预处理的基础上,提出了一个基于深度学习的空气污染物浓度预测平台.该平台架构分为数据采集层、模型层和可视化界面层3个层次,分别实现了数据采集与处理,基于长短期记忆(LSTM)网络模型的污染物浓度预测,以及预测结果可视化的功能,通过对用户个性化模型参数的设置,实现不同时间段污染物浓度时间序列的预测.

关键词：深度学习空气污染预测长短期记忆(LSTM)网络模型大数据

Explicit Isogeometric Topology Optimization Method with Suitably Graded Truncated Hierarchical B-Spline

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1435-1456页

作者： haoran Zhu Xinhao gao Aodi Yang Shuting Wang Xianda Xie Tifan Xiong School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan430074China

This work puts forward an explicit isogeometric topology optimization(ITO)method using moving morphable components(MMC),which takes the suitably graded truncated hierarchical B-Spline based isogeometric analysis as the solver of physical unknown(SGTHB-ITO-MMC).By applying properly basis graded constraints to the hierarchical mesh of truncated hierarchical B-splines(THB),the convergence and robustness of the SGTHB-ITOMMC are simultaneously improved and the tiny holes occurred in optimized structure are eliminated,due to the improved accuracy around the explicit structural ***,an efficient computational method is developed for the topological description functions(TDF)ofMMC under the admissible hierarchicalmesh,which consists of reducing the dimensionality strategy for design space and the locally computing strategy for hierarchical *** apply the above SGTHB-ITO-MMC with improved efficiency to a series of 2D and 3Dcompliance design *** numerical results show that the proposed SGTHB-ITO-MMC method outperforms the traditional THB-ITO-MMCmethod in terms of convergence rate and ***,the proposed SGTHB-ITO-MMC is an effective way of solving topology optimization(TO)problems.

关键词： Isogeometric topology optimization moving morphable components truncated hierarchical B-spline suitably graded hierarchical mesh

Prediction of Low-Permeability Reservoirs Performances Using Long and Short-Term Memory Machine Learning

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Fluid Dynamics & Materials Processing 2022年第5期18卷 1521-1528页

作者： Guowei Zhu Kangliang Guo haoran Yang Xinchen gao Shuangshuang Zhang School of Geosciences Yangtze UniversityWuhan430100China

In order to overcome the typical limitations of numerical simulation methods used to estimate the production of low-permeability reservoirs,in this study,a new data-driven approach is proposed for the case of water-driven hypo-permeable *** particular,given the bottlenecks of traditional recurrent neural networks in handling time series data,a neural network with long and short-term memory is used for such a *** method can reduce the time required to solve a large number of partial differential *** such,it can therefore significantly improve the efficiency in predicting the needed production *** examples about water-driven hypotonic reservoirs are provided to demonstrate the correctness of the method and its ability to meet the requirements for practical reservoir applications.

关键词： Water flooding flow in porous media data-driven LSTM CFD