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| 1 | Fuzzy Control of LED Tunnel Lighting and Energy Conservation显示文摘Current highway tunnel lighting control systems are often manually controlled,resulting in significant energy waste.This article designs a fuzzy control algorithm for tunnel lighting energy control systems.The system uses LED (Light Emitting Diode) lighting,so the fuzzy control algorithm is designed for LED lights.The traffic and the natural illumination level are used as parameters in the intelligent lighting control algorithm.This system has been deployed in the Lengshui tunnel on the 49th provincial highway of Zhejiang province and operated for more than six months.The performance results show that the energy conservation system provides sufficient lighting levels for traffic safety with significant energy conservation. | Hong Zeng Jian Qiu Xingfa Shen Guojun Dai Peng Liu Shuping Le | 2011 | Tsinghua Science and Technology2011，16，6： | 17 |
| 2 | Classification of hyperspectral remote sensing images using frequency spectrum similarity显示文摘An algorithm of hyperspectral remote sensing images classification is proposed based on the frequency spectrum of spectral signature.The spectral signature of each pixel in the hyperspectral image is taken as a discrete signal,and the frequency spectrum is obtained using discrete Fourier transform.The discrepancy of frequency spectrum between ground objects' spectral signatures is visible,thus the difference between frequency spectra of reference and target spectral signature is used to measure the spectral similarity.Canberra distance is introduced to increase the contribution from higher frequency components.Then,the number of harmonics involved in the proposed algorithm is determined after analyzing the frequency spectrum energy cumulative distribution function of ground object.In order to evaluate the performance of the proposed algorithm,two hyperspectral remote sensing images are adopted as experimental data.The proposed algorithm is compared with spectral angle mapper (SAM),spectral information divergence (SID) and Euclidean distance (ED) using the product accuracy,user accuracy,overall accuracy,average accuracy and Kappa coefficient.The results show that the proposed algorithm can be applied to hyperspectral image classification effectively. | WANG Ke GU XingFa YU Tao MENG QingYan ZHAO LiMin FENG Li | 2013 | Science China(Technological Sciences)2013，56，4： | 10 |
| 3 | Correction of Observation Interference on Z component of Geomagnetic Field From DC Power Lines显示文摘为减小直流输电线路对地磁场观测的干扰,采用数学计算的方法精确求解了线路对地磁Z分量的干扰水平。以观测点为原点建立了地磁仪器观测点坐标系,推导了观测点坐标系各坐标轴在地心坐标系中的单位矢量表达式。根据空间矢量点积的定义,得到了空间电流磁场矢量投影到地磁Z分量方向的求解公式。利用推导的公式和直流线路电流磁场三维计算模型,最终求得直流线路对地磁Z分量观测的干扰水平。由此,开发了"直流线路对地磁观测干扰校正系统",并开展了地磁台站和野外联合地磁观测干扰实验。结果表明,直流线路和地磁观测台站距离不超过10km时,提出的数学模型和计算方法误差不超过5%。 | TANG Bo ZHANG Jiangong MENG Suimin LIU Xingfa DENG Changzheng | 2012 | 中国电机工程学报2012，32，30： | 8 |
| 4 | Forest NPP estimation based on MODIS data under cloudless condition显示文摘Based on light-use efficiency model, an MODIS-derived daily net primary production (NPP) model was developed. In this model, a new model for the fraction of photosynthetically active radiation absorbed by vegetation (FPAR) is developed based on leaf area index (LAI) and albedo parameters, and a pho- tosynthetically active radiation (PAR) is calculated from the combination of Bird's model with aerosol optical thickness and water vapor derived from cloud free MODIS images. These two models are inte- grated into our predicted NPP model, whose most parameters are retrieved from MODIS data. In order to validate our NPP model, the observed NPP in the Qianyanzhou station and the Changbai Mountains station are used to compare with our predicted NPP, showing that they are in good agreement. The NASA NPP products also have been downloaded and compared with the measurements, which shows that the NASA NPP products underestimated NPP in the Qianyanzhou station but overestimated in the Changbai Mountains station in 2004. | CHEN LiangFu GAO YanHua LI Li LIU QinHuo GU XingFa | 2008 | Science China Earth Sciences2008，51，3： | 7 |
| 5 | A linear varying coefficient ARCH-M model with a latent variable显示文摘Motivated by the psychological factor of time-varying risk-return relationship, this paper studies a linear varying coefficient ARCH-M model with a latent variable. Due to the unobservable property of the latent variable, a corrected likelihood method is employed for parametric estimation. Estimators are proved to be consistent and asymptotically normal under certain regularity conditions. A simple test statistic is also proposed for testing latent variable effect. Simulation results confirm that the proposed estimators and test perform well.The model is further applied to examine whether the risk-return relationship depends on investor's sentiment in American Market and some explainable results are obtained. | SONG ZeFang ZHANG XingFa LI Yuan XIONG Qiang | 2016 | Science China Mathematics2016，59，9： | 4 |
| 6 | Development in Researches on Reradiation Interference from UHV Power Lines显示文摘Reradiation interference(RRI) from ultra high voltage(UHV) power lines has become a hotspot for researches in electromagnetic(EM) interference between UHV power grids and adjacent radio stations.The mechanism of RRI,numerical simulations,methods of protecting distance calculation,and resonance characteristics of RRI are reviewed in this paper using results of works reported by IEEE and Chinese publications.We conclude in this review that RRI at short and medium wavelengths can be simulated using method of moment(MoM) and two commonly used models,the wire model and the surface model,which have different applicable conditions.We indicate that the accurate simulation of RRI at higher frequencies using uniform geometrical theory of diffraction is still beyond our capability because it requires studies of the relative simulation methods.We also suggest that further researches of the mechanism of RRI and the prediction of resonance frequencies above 1.7 MHz are necessary for dealing with the interference between the existing power lines and radio stations because resonance frequencies proposed by IEEE are less than 1.7 MHz. | TANG Bo ZHAO Zhibin ZHANG Jiangong LIU Xingfa CHEN Bin | 2013 | 高电压技术2013，39，10： | 3 |
| 7 | Uncertainty analysis of cross-calibration for HJ-1 CCD camera显示文摘Radiometric calibration of sensor is the basis of quantitative remote sensing,and uncertainty analysis is critical to ensure the accuracy of cross-calibration.Therefore,firstly,cross-calibration formulas were improved by redefining calibration coefficient and spectral band matching factor.In these formulas,cci was redefined as the calibration coefficient of normalized apparent reflectance,and spectral band matching factor as the ratio of normalized apparent reflectance.Secondly,based on the contrast of ideal and actual conditions in cross-calibration,8 sources of cross-calibration uncertainty were proposed:calibration uncertainty of standard sensor;pixel matching uncertainty;spectral band matching factor uncertainty caused by site altitude setting error,atmospheric parameters setting error,surface spectrum source,surface bidirectional reflectance characteristic,and error of atmospheric radiative transfer model;and uncertainty caused by other factors which were not considered.Finally,the contribution of each uncertainty was further analyzed and discussed for the HJ-1 CCD camera.The results provide many valuable references for evaluating the feasibility of alternative cross-calibration measurements. | WANG Zuo XIAO PengFeng GU XingFa FENG XueZhi LI XiaoYing GAO HaiLiang LI Hui LIN JinTang ZHANG XueLiang | 2013 | Chinese Science Bulletin2013，58，7： | 3 |
| 8 | Moving Average Model with an Alternative GARCH-Type Error显示文摘Motivated by the double autoregressive model with order p(DAR(p) model), in this paper,we study the moving average model with an alternative GARCH error. The model is an extension from DAR(p) model by letting the order p goes to infinity. The quasi maximum likelihood estimator of the parameters in the model is shown to be asymptotically normal, without any strong moment conditions.Simulation results confirm that our estimators perform well. We also apply our model to study a real data set and it has better fitting performance compared to DAR model for the considered data. | Huafeng ZHU Xingfa ZHANG Xin LIANG Yuan LI | 2018 | Journal of Systems Science and Information2018，9，2： | 2 |
| 9 | Improvement of Glacial Lakes Detection under Shadow Environment Using ASTER Data in Himalayas, Nepal显示文摘The detection of glacial lake change in the Himalayas, Nepal is extremely significant since the glacial lake change is one of the crucial indicators of global climate change in this area, where is the most sensitive area of the global climate changes. In the Himalayas, some of glacial lakes are covered by the dark mountains′ shadow because of their location. Therefore, these lakes can not be detected by conventional method such as Normalized Difference Water Index (NDWI), because the reflectance feature of shadowed glacial lake is different comparing to the ones which are located in the open flat area. The shadow causes two major problems: 1) glacial lakes which are covered by shadow completely result in underestimation of the number of glacial lakes; 2) glacial lakes which are partly identified are considered to undervalue the area of glacial lakes. The aim of this study is to develop a new model, named Detection of Shadowed Glacial Lakes (DSGL) model, to identify glacial lakes under the shadow environment by using Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) data in the Himalayas, Nepal. The DSGL model is based on integration of two different modifications of NDWI, namely NDWIs model and NDWI she model. NDWIs is defined as integration of the NDWI and slope analysis and used for detecting non-shadowed lake in the mountain area. The NDWIshe is proposed as a new methodology to overcome the weakness of NDWIs on identifying shadowed lakes in highly elevated mountainous area such as the Himalayas. The first step of the NDWIshe is to enhance the data from ASTER 1B using the histogram equalization (HE) method, and its outcome product is named ASTER he . We used the ASTER he for calculating the NDWI he and the NDWIshe . Integrated with terrain analysis using Digital Elevation Model (DEM) data, the NDWI she can be used to identify the shadowed glacial lakes in the Himalayas. NDWIs value of 0.41 is used to identify the glacier lake (NDWIs≥0.41), and 0.3 of NDWIshe is used to identify the shadowed glacier lake (NDWIshe≤0.3). The DSGL model was proved to be able to classify the glacial lakes more accurately, while the NDWI model had tendency to underestimate the presence of actual glacial lakes. Correct classification rate regarding the products from NDWI model and DSGL model were 57% and 99%, respectively. The results of this paper demonstrated that the DSGL model is promising to detect glacial lakes in the shadowed environment at high mountains. | CHEN Wenbo FUKUI Hiromichi DOKO Tomoko GU Xingfa | 2013 | Chinese Geographical Science2013，23，2： | 2 |
| 10 | A twin-channel difference model for cross-calibration of thermal infrared band显示文摘Based on the conduction and transformation of the thermal infrared radiative transfer equation of water target,a twinchannel difference model(DM) was proposed to improve the calibration precision by conquering the limitation that the atmospheric condition when image is acquiring cannot be truly obtained in the traditional radiometric simulation calibration method.The analysis of surface,atmosphere and top-of-atmosphere(TOA) radiative energy decomposition demonstrated that the apparent TOA radiance of the uncalibrated channel is the differential combination of two reference channels.The DM avoids impacts from atmospheric temperature and density.The only impact is from water vapor(WV) content.Based on the fitting error analysis of 742 mid-latitude atmospheric profiles(column WV content:0-5×10 3 atm cm) selected from TIGR database,the DM is insensitive to WV content.The maximum error is less than 0.2 K when the view zenith angels(VZAs) of reference channels and uncalibrated channel are less than 30.The error becomes 0.3 K when VZAs range from 30 to 40 and 0.6 K when VZAs are in 40-50.Because the uncertainty increases when VZAs are larger than 50,the best range of VZAs is 30-50.The vicarious calibration results at Lake Qinghai field indicated that the calibration precision of the DM cross-calibration by using MODIS bands 31 and 32 as reference channels to calibrate IRS band 08 is similar to that of vicarious calibration.Therefore,the DM is a reliable alternative tool for sensor on-orbit calibration and validation with high precision and frequency. | LI JiaGuo GU XingFa YU Tao LI XiaoYing GAO HaiLiang LIU Li XU Hui | 2012 | Science China(Technological Sciences)2012，55，7： | 2 |
| 11 | Modeling diurnal variation of ground thermal radiance images using energy balance model and endmember composing technique显示文摘Modeling and analyzing dynamic changes of land thermal radiance scenes play an important role in thermal remote sensing.In this paper,the diurnal variation of ground surface thermal scene is mainly discussed.Firstly,based on the land surface energy balance equation,the diurnal variation of land surface temperatures(LSTs) over bare land covers were simulated by an analytical thermal model with second harmonic terms,and the diurnal LST variation of vegetation canopy was simulated using the Cupid model.Secondly,normalized difference vegetation index(NDVI),normalized difference water index(NDWI),and ratio resident-area index(RRI) were used to evaluate the endmember abundance of four land cover types including vegetation,bare soil,impervious and water area,which were calculated from IKONOS visible and near infrared(VNIR) bands.Finally,the thermal radiance scenes at various times and view angles were modeled based on the linear-energy-mixing hypothesis.The results showed that the simulated daily LST variations for vegetated and bare surfaces are correlated with the measured values with a maximum standard deviation of 2.7°C,that land thermal radiant textures with high-resolution are restored from the linear-energy-mixing method,and that the information abundance of the scene are related to the distribution of land cover,the imaging time,and the view angle. | ZHAO LiMin GU XingFa YU Tao WAN Wei XIONG Pan XIE YanHua ZHANG Lun | 2012 | Science China(Technological Sciences)2012，55，11： | 2 |
| 12 | WEEE recovery strategies and the WEEE treatment status in China显示文摘 | WENZHI HE GUANGMING LI XINGFA MA ETC | 2006 | Journal of Hazardous Materials2006，136，： | 1 |
| 13 | A simple biomolecule-assisted hydrothermal approach to antimony sulfide nanowires 显示文摘 | CHEN Xiangying ZHANG Xingfa QIAN Yitai | 2005 | Solid State Commun2005，134，： | 1 |
| 14 | CFD simulation to the flow field of Venturi injector显示文摘 | Huang Xingfa Li Guangyong Wang Miao | 2009 | IFIP International Federation for Information Processing2009，294，2： | 1 |
| 15 | Water target based cross-calibration of CBERS-02 CCD camera with MODIS data显示文摘 | Junwu Tang Xingfa Gu Shengli Niu Chaofei Ma Xiangjun Min | 2005 | Science in China Series E Engineering & Materials Science2005，，2： | 1 |
| 16 | Hydrazine and thermal reduction of graphene oxide: Reaction mech- anisms,product structures,and reaction design显示文摘 | Gao Xingfa Joonkyung Jang Shigeru Nagase | 2010 | Phys Chem C2010，114，： | 1 |
| 17 | Comparison of droplet distributions from fluidic and impact sprinklers显示文摘To adapt to the trend toward low-energy precision irrigation, the droplet distributions for two new prototype sprinklers, outside signal sprinkler(OS) and fluidic sprinkler(FS), were compared with impact sprinkler(IS). A laser precipitation monitor was used to measure the droplet distributions. Droplet size and velocity distributions were tested under four operating pressures for nozzles 1.5 m above the ground. For the operating pressures tested, the mean OS, FS and IS droplet diameters ranged from 0 to 3.4, 0 to 3.5, 0 to 4.0 mm, respectively.The mean OS and FS droplet velocities ranged from 0 to6.3 m$s–1, whereas IS ranged from 0 to 6.3 m$s–1. Being gas-liquid fluidic sprinklers, droplet distributions of the OS and FS were similar, although not identical. IS mostly produced a 0.5 mm larger droplet diameter and a 0.5 m$s–1greater velocity than OS and FS. A new empirical equation is proposed for determination of droplet size for OS and FS, which is sufficiently accurate and simple to use. Basic statistics for droplet size and velocity were performed on data obtained by the photographic methods. The mean droplet diameter(arithmetic, volumetric and median)decreased and the mean velocity increased in operating pressure for the three types of sprinkler. | Xingye ZHU Shouqi YUAN Junping LIU Xingfa LIU | 2015 | Frontiers of Agricultural Science and Engineering2015，2，1： | 1 |
| 18 | 显示文摘 | Ma Xingfa Li Guang Xu Huizhong | 2006 | Thin Solid Films2006，，515： | 1 |
| 19 | Adsorption of p -nitroaniline from aqueous solutions onto activated carbon fiber prepared from cotton stalk显示文摘 | Kunquan Li Zheng Zheng Jingwei Feng Jibiao Zhang Xingzhang Luo Guohua Zhao Xingfa Huang | 2008 | Journal of Hazardous Materials2008，，2： | 1 |
| 20 | Real time deter- mination of irrigalion scheduling for micro--irrigated orchards 显示文摘 | Huang xingfa Li Guangyong Zeng Dechao | 2002 | Transactions of the CASE2002，18，： | 1 |
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