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Street-Level Landmarks Acquisition Based on SVM Classifiers

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Computers, Materials & Continua 2019年第5期59卷 591-606页

作者： Ruixiang Li Yingying Liu Yaqiong Qiao te Ma Bo Wang Xiangyang Luo State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou450001China Zhengzhou Science and technology Institute Zhengzhou450001China Henan Institute of Animal Husbandry Economics Zhengzhou450044China State University of New York at Buffalo New York14260-1660United States

High-density street-level reliable landmarks are one of the important foundations for street-level ***,the existing methods cannot obtain enough street-level landmarks in a short period of *** this paper,a street-level landmarks acquisition method based on SVM(Support Vector Machine)classifiers is ***,the port detection results of IPs with known services are vectorized,and the vectorization results are used as an input of the SVM ***,the kernel function and penalty factor are adjusted for SVM classifiers training,and the optimal SVM classifiers are *** that,the classifier sequence is constructed,and the IPs with unknown service are classified using the ***,according to the domain name corresponding to the IP,the relationship between the classified server IP and organization name is *** experimental results in Guangzhou and Wuhan city in China show that the proposed method can be as a supplement to existing typical methods since the number of obtained street-level landmarks is increased substantially,and the median geolocation error using evaluated landmarks is reduced by about 2 km.

关键词： Landmarks acquisition SVM street-level IP geolocation

Rational design of graphene/polymer composites with excellent electromagnetic interference shielding effectiveness and high thermal conductivity: a mini review

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Journal of Materials Science & technology 2022年第22期117卷 238-250页

作者： Xue Tan Qilong Yuan Mengting Qiu Jinhong Yu Nan Jiang Cheng-te Lin Wen dai Key Laboratory of Marine Materials and Related technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and Engineering(NIMTE)Chinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The integration and miniaturization of chips lead to inevitable overheating and increasing electromagnetic interference (EMI) problems, which threaten the performance, stability, and lifetime of electroniccomponents. Therefore, it is important to improve the heat dissipation and EMI shielding performancein device packaging for the steady operation of electronic products. In recent years, due to its intrinsic superior thermal conductivity, proper electrical conductivity, light-weight, and structural adjustability,graphene has been widely used as high thermal and conductive fillers incorporated in the polymer matrix to improve the thermal conductivity and electrical conductivity of composites. This review concludesthe recent development of graphene/polymer composites by using graphene as fillers to improve thethermal conductivity and EMI shielding effectiveness (EMI SE). The structure of graphene embedded inthe composites varies from zero-dimension (0d), one-dimension (1d) to two-dimensions (2d). Moreover,highly thermally and electrically conductive fillers with different dimensions were also modified on thegraphene to improve the composite performance. Finally, this review also makes prospects for the development trend of graphene/polymer composites with high thermal conductivity and EMI SE in the future.

关键词： Graphene/polymer composites Structural design Electromagnetic interference shielding Thermal conductivity

Radial Keratotomy:Eleven-year Experiences

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眼科学报 1992年第3期8卷 99-103页

作者： te-Tsaw Chen te Tsaw Eye Center,department of Ophthalmology,Taipei Medical College,Taipei,China te Tsaw Eye Center Department of Ophthalmology Taipei Medical College China.

during the period from 1980 to 1991,Radial Keratotomy(RK)hadbeen done by the author under topical anesthesia in more than 10000 cases,mostly on both eyes at the same *** patients had myopia with apreoperative refractive error between 1.5 and 20.0 diopters(d).The surgicaltechnique consisted of 4,8,16 incisions using a diamond knife with micrometerand the diameter of the central clear zone was mostly 3.0mm and determinedby preoperative refractive *** different procedures were tried to im-pro...

关键词： radial keratoplast (RK) topical anesthesia results complications

temporal variations in geochemistry of hydraulic fracturing fluid and flowback water in a tight oil reservoir

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Petroleum Science 2023年第5期20卷 3013-3021页

作者： Jie Tian Liang Wang Li-Pin Ni Li-Wei Mou Shu-te Su Mehdi Ostadhassan College of Energy Chengdu University of TechnologyChengdu610059SichuanChina Geological Research Institute CNPC LoggingXi'an710000ShaanxiChina Exploration and development Research Institute Xinjiang Oilfield BranchPetroChinaKaramay834000XinjiangChina Institute of Geosciences Marine and Land Geomechanics and GeotectonicsChristian-Albrechts Universit€atKiel24118Germany

Hydraulic fracturing facilitates the development and exploitation of unconventional *** this study,the injected hydraulic fracturing fluid(HFF)and flowback and produced water(FPW)in tight oil reservoirs of the Lucaogou Formation in the Junggar Basin are temporally sampled from day 1 to day *** is used for fracturing,and HFF is *** chemical and isotopic parameters(including the water type,total salinity,total dissolved solids(TdS),pH,concentrations of Na^(+),Cl^(-),Ba^(+),K^(+),Fe^(2+)+Fe^(3+),and CO_(3)^(2-),dd,and δ^(18)O)are experimentally obtained,and their variations with time are systematically analyzed based on the flowback *** results show that the water type,Na/Cl ratio,total salinity,and TdS of the FPW change periodically primarily due to the HFF mixing with formation water,thus causing δd and δ^(18)O to deviate from the meteoric water line of *** of watererock interaction(WRI),the concentrations of Fe^(2+)+Fe^(3+)and CO_(3)^(2-)of the FPW increase over time,with the solution pH becoming more ***,based on the significant changes observed in the geochemistry of the FPW,three separate time intervals of flowback time are identified:Stage Ⅰ(days),where the FPW is dominated by the HFF and the changes in ions and isotopes are mainly caused by the WRI;Stage Ⅱ(10-37 days),where the FPW is dominated by the addition of formation water to the HFF and the WRI is weakened;and finally,Stage Ⅲ(>37 days),where the FPW is dominated by the chemistry of the formation *** methodology implemented in this study can provide critical support for the source identification of formation water.

关键词： Tight oil reservoirs Isotope Flowback and produced water(FPW) Inorganic ions Hydraulic fracturing fluid(HFF)

terahertz time-domain spectroscopy of some pentoses

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Science China Chemistry 2006年第3期49卷 204-208页

作者： GE Min ZHAO Hongwei JI te YU Xiaohan WANG Wenfeng LI Wenxin Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

The well-resolved absorption spectra of d-xylose,d-ribose,d-arabinose,d-lyxose and other related substances in the spectral region between 0.3 and 2.0 THz are measured using tera-hertz time-domain spectroscopy(THz-TdS)at 295 *** the absorption spectra of different chemicals,we can distinguish the samples *** THz-TdS is demonstrated to be a power and characteristic spectral tool,which is highly sensitive to the minor changes of the molecular structures and can be applied to detect and analyze similar materials.

关键词： pentoses terahertz time-domain spectroscopy(THz-TdS).

terahertz identification and quantification of penicillamine enantiomers

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Nuclear Science and techniques 2013年第1期24卷 12-16页

作者： JI te ZHAO Hongwei HAN Pengyu CHEN Min XIAO Tiqiao Shanghai Institute of Applied Physics Chinese Academy of Sciences Center for terahertz Research Rensselaer Polytechnic Institute

Identification and characterization of L-, d- and dL- penicillamine were demonstrated by terahertz time-domain spectroscopy (THz-TdS). To understand the physical origins of the low frequency resonant modes, the density functional theory (dFT) was adopted for theoretical calculation. It was found that the collective THz frequency motions were decided by the intramolecular and intermolecular hydrogen bond interactions. Moreover, the quantification of penicillamine enantiomers mixture was demonstrated by a THz spectra fitting method with a relative error of less than 3.5%. This technique can be a valuable tool for the discrimination and quantification of chiral drugs in pharmaceutical industry.

关键词：太赫兹时域光谱技术青霉胺量化对映体 THz-TdS 识别密度泛函理论氢键相互作用

Simultaneous enhancement in electrical conductivity and Seebeck coefficient by single-to double-valley transition in a dirac-like band

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npj Computational Materials 2022年第1期8卷 2239-2246页

作者： Yu dai Wenjiang Zhou Hyun-Jung Kim Qichen Song Xin Qian te-Huan Liu Ronggui Yang School of Energy and Power Engineering Huazhong University of Science and TechnologyWuhanHubei430074China Peter Grünberg Institut and Institute for Advanced Simulation Forschungszentrum Jülich and JARAD-52425JülichGermany department of Chemistry and Chemical Biology Harvard UniversityCambridgeMA02138USA

Snte possesses a single-to double-valley transition in the conduction band minimum when a compressive strain is *** a tight-binding analysis,it is shown that the variation of the band structure is attributed to the strain-induced delocalization of both the Sn-5s orbitals and te-5p orbitals with different angular *** effect can la.gely increase the electron density of states near the band edge and thus keep the Fermi level of the compressed Snte closer to it,where the electrons have lower scattering *** strain-induced double valleys lead to simultaneous increases in the electrical conductivity and the Seebeck coefficient and thereby nearly four times the enhancement of the power factor at the doping concentration of 5×10^(19) cm^(–3).This work suggests a feasible concept that can be employed to promote the power factor of a dirac semiconductor via manipulating the valley degeneracy in the conduction band minimum.

关键词： conductivity double coefficient

An adaptive stable observer for on board auxiliary inverters with online current identification strategy

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Journal of Central South University 2017年第4期24卷 819-828页

作者： LI Wei LIU You-mei CHEN te-fang dENG Jiang-ming School of Information Science and Engineering Central South University Changsha 410083 China Zhuzhou Electric Locomotive Limited Company CRRC Zhuzhou 412001 China School of Traffic Transportation Engineering Central South University Changsha 410075 China

An adaptive stable observer with output current online identification strategy for the auxiliary inverters applied in advanced electric trains, such as high speed railway, urban rail, subway and maglev trains, is proposed. The designed observer is used to estimate the state variables, i.e. controllable duty ratio and current components in d-q-o rotary reference frame. The convergence of the observer estimation error is analyzed with consideration of uncertain level variation of input voltage at direct current(dC) side and sufficient conditions are given to prove its practical stability. Experimental results are shown to confirm the effectiveness of the proposed observer.

关键词： auxiliary inverter adaptive observer online identification Lyapunov function parameter variation

g-C_(3)N_(4)Qds@Go/MoS_(2)二维复合半导体催化剂的合成及光催化性能研究

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化学研究与应用 2024年第4期36卷 728-737页

作者：阿更兄马尚文马海燕李淑依吴可量任铁真巴音郭楞职业技术学院石油化工学院新疆库尔勒841000 南阳理工学院生物与化学工程学院河南南阳473000 河南工业微生物资源与发酵利用重点实验室河南南阳4730002 新疆大学化工学院新疆乌鲁木齐831100

为了解决MoS_(2)纳米片容易堆积、导电性低的科学问题,通过水热法在MoS_(2)催化剂水热引入石墨烯增强其导电性,制备出Go/MoS_(2)纳米片,随后负载上已合成的量子点(g-C_(3)N_(4)QdS),构建出g-C_(3)N_(4)QdS@Go/MoS_(2)三元二维复合催化剂... 详细信息

为了解决MoS_(2)纳米片容易堆积、导电性低的科学问题,通过水热法在MoS_(2)催化剂水热引入石墨烯增强其导电性,制备出Go/MoS_(2)纳米片,随后负载上已合成的量子点(g-C_(3)N_(4)QdS),构建出g-C_(3)N_(4)QdS@Go/MoS_(2)三元二维复合催化剂,用于光催化产氢。g-C_(3)N_(4)量子点由于其独特的电子结构和物理化学特性,其能带与MoS_(2)较为匹配,作为半导体材料也可以激发产生光生载流子,促进了整体催化产氢的效率。在本研究中复合催化剂显示出较高的光催化性能,2.5 h氢气产量为7.25μmol/g,相较于Go/MoS_(2),提升了近1.5倍。

关键词： MoS_(2)催化剂石墨烯 g-C_(3)N_(4)量子点光催化制氢