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| 1 | 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 |
| 2 | 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 |
| 3 | 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 |
| 4 | 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 |
| 5 | 显示文摘 | Ma Xingfa Chen Hongzheng Shi Minmin | 2005 | Thin Solid Films2005，489，12： | 1 |
| 6 | Initial research on the polarized reflectance of typical urban surface types measured by the Directional Polarimetric Camera显示文摘This paper retrieves the bidirectional polarization distribution functions (BPDFs) of the distinct urban cover in the Pearl River Delta (PRD) region employing the high spatial resolution of multi-angle polarized measurements made by the Directional Polarimetric Camera (DPC).The BPDF operational products of MICROPOL and POLDER measurements were used to validate the BPDF products of the DPC,with the results demonstrating that the BPDF product of the DPC measurements accurately expresses the surface polarized reflectance.The polarized reflectance of distinct surface types in the PRD region was studied using the DPC measurements.The results demonstrate that the polarized reflectances of different surface types differ and decrease as the normalized difference vegetation index increases.The polarized reflectance of a distinct surface type in the PRD region decreases with increasing scattering angle.The basic theory of investigating surface properties using multi-angle polarized measurements is proposed. | XIE DongHai GU XingFa CHENG TianHai YU Tao LI ZhengQiang CHEN XingFeng CHEN Hao GUO Jing | 2011 | Science China Earth Sciences2011，54，8： | 1 |
| 7 | Preparation of Water Soluble Poly (aniline) and its Gas - sensitivity 显示文摘 | Ma Xingfa Wang Mang Chen Hongzhen | 2005 | Green Chemistry2005，7，7： | 1 |
| 8 | High Gas- sensitivity and Selectivity of Fluorinated Zinc Phthalocyanine Film to Some Non - oxidizing Gases at Room Temperature 显示文摘 | Ma Xingfa Chen Hongzheng Shi Minmin | 2005 | Thin Solid Films2005，489，12： | 1 |
| 9 | Synthesis and magnetic properties of nickel and cobalt nanoparticles obtained in DMF solution 显示文摘 | Zhong jie Zhang Xiang ying Chen Xingfa Zhang Chengwu Shi | 2006 | Solid State Communications2006，139，40： | 1 |
| 10 | 重复穿刺活检中高级别上皮内瘤对前列腺癌的预测价值(英文)显示文摘Objective: The significance of isolated high-grade prostatic intraepithelial neoplasia in initial biopsy as an predic-tor for prostate cancer has been extensively research, and the true relationship remnant is no clear till now. The aim of this study is to evaluate prediction value of cancer on repeat biopsy in patients with high-grade prostatic intraepithelial neoplasia, using multivariate analysis. Methods: Thirty-eight men with a diagnosis of isolated high-grade prostatic intraepithelial neo-plasia in initial needle biopsy were studies, in the Fist Affiliated Hospital of Medical School of Xi'an Jiaotong University, from January 2003 to March 2009. These samples were using immunostaining of p63 and 34βE12 and P504s, with a median fol-low-up of 525 (range, 7 to 1650) days, and to researched the incidence of subsequent prostate cancer, and to predicted the risk of prostate cancer in clinicopathological parameters of isolated high-grade prostatic intraepithelial neoplasia on repeat biopsies by logistic regression analysis. Results: There were 10 of 38 (26.3%) men with prostate cancer on repeat biopsies after diagnosis isolated high-grade prostatic intraepithelial neoplasia in initial biopsy, of the rates of prostate cancer were 80% for micropapillary and 75% for cribriform high-grade prostatic intraepithelial neoplasia (P < 0.05), respectively. The positive cores of isolated high-grade prostatic intraepithelial neoplasia was the important for the risk of prostate cancer using Multi-factor logistic regression analysis. The time range in 30 to 690 days was stronger risk for prostate cancer detection after diagnosis isolated HGPIN in initial biopsy. p63 and 34βE12 were disrupted positive expression, and P504S was weak posi-tive expression in the 61% isolated high-grade prostatic intraepithelial neoplasia. Conclusion: Isolated high-grade prostatic intraepithelial neoplasia on repeat biopsy conferred a 26.3% risk of prostate cancer, and this risk level is lower than the previ-ously reported risk of 24% to 58%. The number of positive cores and the histopathological pattern with high-grade prostatic intraepithelial neoplasia on initial biopsy was significantly associated with the risk of cancer. | Huilian Hou Xu Li Xingfa Chen Chunbao Wang Guanjun Zhang Honghan Wang Huilin Gong Yuan Deng Min Wang Xuebin Zhang | 2011 | The Chinese-German Journal of Clinical Oncology2011，10，7： | 0 |
| 11 | Error-space estimate method for generalized synergic target tracking显示文摘To improve the tracking accuracy and stability of an optic-electronic target tracking system,the concept of generalized synergic target and an algorithm named error-space estimate method is presented.In this algorithm,the motion of target is described by guide data and guide errors,and then the maneuver of the target is separated into guide data and guide errors to reduce the maneuver level.Then state estimate is implemented in target state-space and error-space respectively,and the prediction data of target position are acquired by synthesizing the filtering data from target state-space according to kinematic model and the prediction data from errorspace according to guide error model.Differing from typical multi-model method,the kinematic and guide error models work concurrently rather than switch between models.Experiment results show that the performance of the algorithm is better than Kalman filter and strong tracking filter at the same maneuver level. | Ming CEN Chengyu FU Ke CHEN Xingfa LIU | 2009 | Frontiers of Electrical and Electronic Engineering in China2009，4，1： | 0 |
| 12 | Jacobi Spectral Collocation Method Based on Lagrange Interpolation Polynomials for Solving Nonlinear Fractional Integro-Differential Equations显示文摘In this paper,we study a class of nonlinear fractional integro-differential equations,the fractional derivative is described in the Caputo sense.Using the properties of the Caputo derivative,we convert the fractional integro-differential equations into equivalent integral-differential equations of Volterra type with singular kernel,then we propose and analyze a spectral Jacobi-collocation approximation for nonlinear integro-differential equations of Volterra type.We provide a rigorous error analysis for the spectral methods,which shows that both the errors of approximate solutions and the errors of approximate fractional derivatives of the solutions decay exponentially in L^(∞)-norm and weighted L^(2)-norm. | Xingfa Yang Yin Yang Yanping Chen Jie Liu | 2018 | Advances in Applied Mathematics and Mechanics2018，10，6： | 0 |
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