检索结果-南通市图书馆

The quantification of remote sensing

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2005年第S2期48卷 1-11页

作者： GU Xingfa1,2.3,TIAN Guoliang1,2. LI Xiaowen1,2.& GUO Jianning4 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, China {2., beijing 100101, China 3. Institut national de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 4. China center for Resource Satellite Data and Application, beijing 100830, China State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

The paper firstly defined the remote sensing information quantification, analyzed the necessity of developing remote sensing quantification, figured out the application guidelines requirement, and pointed out the importance of quantification research. Then taking the remote sensing application research of CBERS-02.data quantification as the example, the paper described the whole quantification system of “remotely sensed digital signal-radiation information-field parameter inversion”. Finally the paper gave the prospect for the development trend of the quantitative remote sensing.

关键词： remote sensing information quantification CBERS-02 radiometric calibration surface parame- ter reversion.

An integrated decision method for prediction of tropical cyclone movement by using genetic algorithm

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2005年第3期48卷 429-440页

作者： YANG Yuanqin1 & WANG Jizhi2.1. national Meteorological center, {2. 100081,China 2. Chinese Academy of Meteorological Sciences, {2. 100081, China national Meteorological center Beijing China Chinese Academy of Meteorological Sciences Beijing China

In this study an integrated decision method for the multi-prediction results of tropical cyclone movements by using genetic algorithm (GA) has been adopted. A genetic learning artifi- cial neural network (GLANN) as a learning mechanism for track prediction was developed through training with the huge samples of typhoon tracks from 1884 to 2.02. The prediction of typhoon motion is to consider how to suit the dynamic change of environment, where typhoon passed through. The neural network structure is described by GA. A fitness function for choice of GA is given to approach the maximum of fitness (the minimum of the errors). Parallel comparing analyses for prediction abilities of unusual typhoon tracks in recent years by GLANN with multi-forecast methods were conducted. More types of cases were employed in the comparing analyses, which consist of the typhoon, Winnie, No.11, in 1997, characterized by a long life over the ocean and in the mainland with severe effect on China, the 10 unusual typhoon tracks in the 1990s, the tracks with landfall and affected action in 1998 and the typhoons born in the Northwestern Pacific and the South China Sea in 2.00, including the 2.—48 h forecast, etc. The results indicated that for prediction ability of typhoon tracks, specially for unusual typhoons, GA decision-making developed in this study is superior to the others.

关键词： genetic algorithm, integrated decision, prediction of tropical cyclone.

Absolute radiometric calibration of CBERS-02.IRMSS thermal band

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2.3, GU Xingfa1,3,4, YU Tao1,3, ZHANG Yuxiang5, CHEN Liangfu1,3, LI Xiaoying1,2.3, LI Xiaowen1,3 & HE Liming6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, China 2. Graduate University of Chinese Academy of Sciences, beijing 100039, China 3. The center for national spaceborne demonstration, beijing 100101, China 4. Institut national de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. national Satellite Meteorological center, beijing 100081, China 6. State Environmental Protection Administration, beijing 10002., China State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Graduate University of Chinese Academy of Sciences The center for national Spa

Based on the laboratory calibration before launch of CBERS-02.IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of China on Aug. 17, 2.04 are carried out in this research. When making onboard blackbody calibration of CBERS-02.IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02.IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2.04 to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02.IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53 (gain, unit: DN/W m?2.r?1μm?1) and 44.92.(offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

Polynomial analysis of canopy spectra and biochemical component content inversion

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2005年第10期48卷 1780-1791页

作者： YAN Chunyan1, LIU Qiang1, NIU Zheng1, WANG Jihua2. HUANG Wenjiang2.& LIU Liangyun 2.1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, China 2. {2. Engineering Research center for Information Technology in Agriculture, beijing 100089, China Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University national Engineering Research center for Information Technology in Agriculture

A polynomial expression model was developed in this paper to describe directional canopy spectra, and the decomposition of the polynomial expression was used as a tool for re-trieving biochemical component content from canopy multi-angle spectra. First, the basic formula of the polynomial expression was introduced and the physical meaning of its terms and coeffi-cients was discussed. Based on this analysis, a complete polynomial expression model and its decomposition method were given. By decomposing the canopy spectra simulated with SAILH model, it shows that the polynomial expression can not only fit well the canopy spectra, but also show the contribution of every order scattering to the whole reflectance. Taking the first scattering coefficients a10 and a01 for example, the test results show that the polynomial coefficients reflect very well the hot spot phenomenon and the effects of viewing angles, LAI and leaf inclination angle on canopy spectra. By coupling the polynomial expression with leaf model PROSPECT, a canopy biochemical component content inversion model was given. In the simulated test, the canopy multi-angle spectra were simulated by two different models, SAILH and 4-SCALE re-spectively, then the biochemical component content was retrieved by inverting the coupled polynomial expression + PROSPECT model. Results of the simulated test are promising, and when applying the algorithm to measured corn canopy multi-angle spectra, we also get relatively accurate chlorophyll content. It shows that the polynomial analysis provides a new method to get biochemical component content independent of any specific canopy model.

关键词： polynomial expression, canopy spectra, decomposition, biochemical component content, inversion.

Radiometric cross-calibration of the CBERS-02.CCD camera with the TERRA MODIS

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2005年第S2期48卷 44-60页

作者： LI Xiaoying1,2.3, GU Xingfa1,3,4, MIN Xiangjun5, YU Tao1,3, FU Qiaoyan5, ZHANG Yong1,2.3 & LI Xiaowen1,3 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, China 2. Graduate University of Chinese Academy of Sciences, beijing 100039, China 3. The center for national spaceborne demonstration, beijing 100101, China 4. Institut national de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. China center for Resource Satellite Data and Application, beijing 100830, China State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

For the application of the CCD camera, the most important payload on CBERS-02. the key is to provide long-term stable radiometric calibration coefficients. Although the vicarious calibration had been proved successful, it had its limitations such as test site requirement and unsuitable for historical data. Cross-calibration is one of the alternative methods, but it needs synchro surface spectrum to achieve spectral band matching factors. Our effort is to probe the influences on these factors. Simulations with a lot of surface spectrum showed that the factors changed with the viewing geometry, atmospheric condition and surface targets. However, simulating with the same viewing geometry and atmospheric condition, the spectral band matching factors of the same or similar surface targets’ spectrum acquired from different dates and different places would like to be consistent to each other within 1%―5%. Thus, the synchro measurement data can be substituted by the same or similar target from other source. Based on this method, using the MODIS as the reference, the cross-calibration was performed for CCD camera. The research demonstrated that the traditional method with single calibration site was inappropriate for CCD camera, since the offsets for its four spectral bands were not zeros. With four calibration sites, these offsets were obtained. And the camera was detected to degrade with dates based on four times of cross-calibrations.

关键词： CBERS-02 CCD camera cross-calibration the spectral band matching factors.

In flight MTF monitoring and compensation for CCD camera on CBERS-02

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2005年第S2期48卷 29-43页

作者： GU Xingfa1,2.3, LI Xiaoying1,2.4, MIN Xiangjun5, YU Tao1,2. SUN Jijuan5, ZENG Yong1,2.4, XU Hua1,2.& GUO Ding2.6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, China {2., beijing 100101, China 3. Institut national de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 4. Graduate University of Chinese Academy of Sciences, beijing 100039, China 5. China center for Resource Satellite Data and Application, beijing 100830, China 6. University of Electronic Science and Technology of China, Chengdu 610054, China State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University The center for national {2. demonstration

In this article, the approach of simulating ideal tarp scene was proposed to determine the MTF for CCD camera on CBERS-02. The MTF acquired from this technique was compared to those from some common methods. MTFs achieved from different approaches were employed to compensate the CCD images based on three restoration algorithms: the iterative method, the Wiener filter and the modified inverse filter (MIF). The two-dimensional MTF was established with the value at frequency 0.5 for 45° directional MTF as the value at its four corners. This article addressed the variations of the restored CCD images with different techniques of constructing two-dimensional MTF, restoring algorithms and determining the in-flight MTFs. Results showed images restored with the MTF determined from the technique of simulating ideal tarp scene represent the real scene best. And the restoration technique based on the MIF would produce better restored images than the other two techniques. This research also demonstrated that the two-dimensional MTF used for restoration should be interpolated under the control of the MTF for 45° axis, rather than by multiplying the cross-orbit MTF with along-orbit MTF.

关键词： CBERS-02 CCD MTF the technique of simulating ideal tarp scene.

Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2005年第7期48卷 939-949页

作者： SHAO Xuemei1, HUANG Lei1, LIU Hongbin2. LIANG Eryuan1, FANG Xiuqi3 & WANG Lili1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, China 2. national Climate {2., beijing 100081, China 3. beijing Normal University, beijing 100875, China Institute of Geographic Sciences Natural Resources Research Chinese Academy of Sciences Beijing 100101 China national Climate center Beijing 100081 China beijing Normal University Beijing 100875 China

Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD152.—1633 and 1933—2.01, whereas dry intervals in 142.—1519 and 1634—1741. In ad- dition, the magnitude in precipitation variation was lower before 1430 with about 15 mm, but it increased to 30 mm during the period of 1430 to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 2.st century.

关键词： northeastern part of the Qaidam Basin tree-ring width series of Qilian juniper precipitation reconstruction in 1000 years.

The study of two-color excitation upconversion of Pr(0.5)Yb(3):ZBLAN

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2.1. Applied Optics beijing Area Major Laboratory, Analysis and testing center, beijing Normal University, beijing 100875, China 2. Peking University, Physics School, beijing 100871, China Applied Optics beijing Area Major Laboratory Analysis and testing center Beijing Normal University Beijing China Physics School Peking University Beijing China

The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 631.8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3+)→1I6(Pr3+) and 1G4(Pr3+)→3P1(Pr3+)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3+)→3P2.Pr3+), and the 803.7 nm upconversion excitation transition 3H6(Pr3+)→1D2.Pr3+). The upconversion excitation transition 1G4(Pr3+)→1I6(Pr3+) is strong because its oscillator strength f = 2..040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3):ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

Experimental study on fire smoke movement in a multi-floor and multi-room building

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2005年第3期48卷 292-304页

作者： ZHONG Maohua 1, 2., LI Peide 2., LIU Tiemin 1 , WEI Xing 1, 2.& LIAO Guangxuan 2.1. national center of Safety Science and Technology, State Administration of Work Safety, {2. 10002., China 2. State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 2.002., China national center of Safety Science and Technology State Administration of Work Safety Beijing 100029 China

Fire smoke movement of multi-floor and multi-room (MFMR) fire was studied at the model test building in State Key Laboratory of Fire Science (SKLFS). The ingredient, temperature, air pressure difference and air velocity of smoke were measured and analyzed. Meanwhile, the hazard of smoke ingredient to exposed occupants was analyzed based on the national standard, Occupational Exposure Limit for Hazardous Agents in the Workplace (GBZ2.2.02.. The experimental results showed that the maximum temperature difference in MFMR fire was located along the vertical height from the fire source. With the spreading and diffusion of smoke, the temperature of smoke layer would tend to be no difference. In the fire of woodpile and kerosene, the main smoke ingredients such as SO 2., CO and CO 2.would first exceed human’s average physiological limit, while smoke ingredients such as NO and NO 2.would come behind. Because of the higher fluctuation range and frequency of air pressure difference of smoke in multi-layer building fire, the fire smoke would spread around everywhere of the passageway and made the human evacuation more difficult.

关键词： multi-floor and multi-room,fire experiment,smoke spread,smoke toxicity.