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Lazy learner text categorization algorithm based on embedded feature selection

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Journal of Systems Engineering and Electronics 2009年第3期20卷 651-659页

作者： Yan Peng zheng xuefeng Zhu Jianyong Xiao Yunhong Information Engineering School Univ. Science and Technology Beijing Beijing 100083 P. R. China China State Information Center Beijing 100045 P. R. China

To avoid the curse of dimensionality, text categorization （TC） algorithms based on machine learning （ML） have to use an feature selection （FS） method to reduce the dimensionality of feature space. Although having been widely used, FS process will generally cause information losing and then have much side-effect on the whole performance of TC algorithms. On the basis of the sparsity characteristic of text vectors, a new TC algorithm based on lazy feature selection （LFS） is presented. As a new type of embedded feature selection approach, the LFS method can greatly reduce the dimension of features without any information losing, which can improve both efficiency and performance of algorithms greatly. The experiments show the new algorithm can simultaneously achieve much higher both performance and efficiency than some of other classical TC algorithms.

关键词： machine learning text categorization embedded feature selection lazy learner cosine similarity.

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On the Influence Factors of Second-hand House Prices in First-tier Cities——Empirical Analysis Based on Panel Data

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学术界 2018年第2期 225-236页

作者： Dong Fan zheng xuefeng School of Government Beijing Normal University

With the arrival of the ＂housing stock＂ in first - tier cities, the second - handhousing^market will become the dominant property market. This ardcle aim to the first - tiercities of second - hand housing prices and new home price index for the empirical analysis, thedata related to the cointegration analysis found that the result of the first -tier cities real estatemarket in China, the new home price index is the significant factors influencing the second -hand house price indexi For Beijing, Shanghai second - hand housing and new home price in-dex time series johans test, found that there exists cointegration relationship between two varia-bles,the new city real estate market prices out of a line on the secondary market have clearguide. Therefore, the real estate market regulation aiming at the first -tier cities and the＂housing stock＂ should take the second - hand housing market as the main direction, startingwith the sale price and influencing factors of new houses. At the same time, in different cities,we should adhere to the city＇ s policies, reflect the policy differentiation, promote the reformof the real estate supply side, and promote the return of housing properties.

关键词： first - tier cities second - hand house housing price panel data cointegra-tion johansTest

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Performance improvement of β-Ga2O3 SBD-based rectifier with embedded microchannels in ceramic substrate

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Science China(Information Sciences) 2024年第5期67卷 341-342页

作者： Wen HONG Chao ZHANG Fang ZHANG xuefeng zheng Xiaohua MA Yue HAO State Key Laboratory of Wide-Bandgap Semiconductor Devices and Integrated Technology School of MicroelectronicsXidian University

With the development of integrated circuits, there is a growing demand for higher power devices [1]. Gallium oxide（Ga2O3） holds promise for high power devices due to its wide bandgap and high breakdown electric field strength [2].However, its low thermal conductivity induces severe selfheating effects, limiting its performance and ***, effective thermal management techniques are urgently needed for Ga2O3devices.

关键词： Gallium compounds

Proton irradiation effects on HVPE GaN

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Science China(Technological Sciences) 2012年第9期55卷 2432-2435页

作者： LU Ling HAO Yue zheng xuefeng ZHANG JinCheng XU ShengRui LIN ZhiYu AI Shan MENG FanNa School of Microelectronics Key Lab of Wide Band-Gap Semiconductor Materials and DevicesXidian UniversityXi'an 710071China

GaNs grown by hydride vapor phase epitaxy(HVPE) were irradiated by protons with different *** changes of surface topography of as-grown and irradiated samples were characterized by atomic force microscopy(AFM).The crystal quality and optical properties of GaN films were examined by the variations of the micro-Raman and photoluminescence(PL) spectra with proton *** was observed that the surface became a little more rough after *** Raman spectra indicated that the strain of materials and carrier concentration were not affected by the proton *** full-width at half-maximum(FWHM) of E 2 high phonon mode narrowed,which was consistent with the FWHM of PL near-band-edge emission(BE).The spectra of yellow luminescence and blue luminescence normalized to the intensity of BE demonstrated a little increase of Ga vacancy and a large decrease of O N,which may be the main reason for the change of optical properties.

关键词： vproton irradiation AFM micro-Raman photoluminescence

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TCLOUD: A New Model of Data Storage Providing Public Verifiability and Dynamic Data Recovery for Cloud Computing

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Journal of Software Engineering and Applications 2013年第3期6卷 23-28页

作者： Sultan Ullah xuefeng zheng Feng Zhou School of Computer and Communication Engineering University of Science and Technology Beijing Beijing People Republic of China

Cloud computing is a new paradigm of computing and is considered to be the next generation of information technology infrastructure for an enterprise. The distributed architecture of cloud data storage facilitates the customer to get benefits from the greater quality of storage and minimized the operating cost. This technology also brought numerous possible threats including data confidentiality, integrity and availability. A homomorphic based model of storage is proposed, which enable the customer and a third party auditor to perform the authentication of data stored on the cloud storage. This model performs the verification of huge file’s integrity and availability with less consumption of computation, storage and communication resources. The proposed model also supports public verifiability and dynamic data recovery.

关键词： Data Storage Integrity Confidentiality Cloud Computing

Part of decortication ameliorates dopamine depletion-induced striatal neuron lesions in rats

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解剖学杂志 2021年第S1期44卷 144-145页

作者： Zhu Yaofeng zheng xuefeng Wanlong Lei Department of Anatomy Jishou UniversityJishou 416000China Department of Anatomy Zhongshan School of Medicine SunYat-sen University

The degeneration of dopaminergic neurons can lead to the hyperexcitability of striatal *** motor symptoms of Parkinson's disease(PD)are caused by striatal dopamine *** degeneration of dopaminergic neurons,the reduction of corticostriatal glutamate can reestablish the balance of striatal neurons which leads to relieve the PD pathology ***,the mechanisms that reduction of corticostriatal glutamate can relieve vulnerability of striatal neurons were *** the Golgi staining and electron microscopic analysis,we found that reduction of corticostriatal glutamate that used to decorticate decrease in the total length of dendrites and the density of dendritic spines of the striatal neurons in 6-hydroxydopamine(6-OHDA)lesion-induced PD rat ***,we found that reduction of corticostriatal glutamate recovered mitochondrial membrane potential.

关键词： dopamine cor degeneration

Unidirectional p-GaN gate HEMT with composite source-drain field plates

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Science China(Information Sciences) 2022年第2期65卷 265-266页

作者： Haiyong WANG Wei MAO Shenglei ZHAO Yuanhao HE Jiabo CHEN Ming DU xuefeng zheng Chong WANG Chunfu ZHANG Jincheng ZHANG Yue HAO Key Lab of Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices School of Microelectronics Xidian University

Dear editor,Ga N-on-Si high electron mobility transistors (HEMTs) have attracted attention for power device applications due to their low cost and large-area availability[1].Recently,bidirectional switches are highly desirable in many industrial bidirectional power conversion applications,such as rolling mills,elevators,and wind power *** addition,normally-off unidirectional HEMTs can be valuable devices to implement the high-performance bidirectional switches[2,3].

关键词： Nano CMOS ESD Reliability Hot-carrier Charge trapping

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Part of decortication ameliorates dopamine depletion-induced striatal neuron lesions in rats

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Part of decortication ameliorates dopamine depletion-induced...

Potential association of hyperhomocysteinemia with the progression of IgA nephropathy： a retrospective study

中国解剖学会2021年年会

作者： Zhu Yaofeng zheng xuefeng Wanlong Lei Department of Anatomy Jishou University Department of Anatomy Zhongshan School of Medicine SunYat-sen University

The degeneration of dopaminergic neurons can lead to the hyperexcitability of striatal *** motor symptoms of Parkinson’s disease (PD) are caused by striatal dopamine *** degeneration of dopaminergic neurons,the reduction of corticostriatal glutamate can reestablish the balance of striatal neurons which leads to relieve the PD pathology process.

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Chinese Medical Journal 2014年第10期127卷 1849-1852页

作者： Duan Shuwei Liu Shuwen Sun xuefeng zheng Ying Liu Linchang Yao Feixiang Wu Jie Department of Nephrology Chinese People's Liberation Army General Hospital (301 Hospital) Chinese People's Liberation Army Institute of Nephrology State Key Laboratory of Kidney Diseases (2011DAV00088) National Clinical Research Center of Kidney Diseases (2013BAI09B05) Beijing 100853 China

Background The high blood homocysteine （Hcy） levels found in patients with hyperhomocysteinemia （HHcy） have been implicated in an increased risk of cardiovascular disease morbidity and mortality in end-stage renal disease （ESRD）.This study investigated the association of HHcy with progression of IgA *** We analyzed 108 participants newly diagnosed with IgA nephropathy between August 2005 and August 2007 in the Department of Nephrology,Chinese People＇s Liberation Army General *** association between clinicopathological factors and the Hcy levels were analyzed by Logistic regression and those with ESRD risk were analyzed by Cox *** Patients were aged （35.71±10.73） years and included 45.71％ women and 12.04％ patients with *** multivariate Logistic regression analysis,HHcy was associated with arterial lesions （OR 2.60; 95％ CI 1.55-4.34; P＜0.001） even when age,body mass index,estimated glomerular filtration rate,mean arterial pressure,and initial proteinuria were taken into *** follow-up was （67.37±16.21） *** was also associated with worse ESRD-free survival （HR 4.71; 95％ CI 1.45 to 15.31; P=0.010）.Conclusion HHcy is associated with the risk of intrarenal arterial lesions and may be useful for estimating the prognosis of IgA nephropathy.

关键词： IgA nephropathy hyperhomocysteinemia prognosis