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Parameter influence analysis for Velocity-Measurement Navigation Target Source with Asymmetric Spatial Heterodyne Technology based on Doppler Effect

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Parameter Influence Analysis for Velocity-Measurement Naviga...

The status,challenges,and trends:an interpretation of technology roadmap of intelligent and connected vehicles in China(2020)

新型导航技术及应用研讨会

作者： Zhang Wei Lu Xi Du Yang Shanghai Institute of Satellite Engineering Shanghai Key Laboratory of Deep Space Exploration Technology

With the start point of Doppler effect, the method principle of velocity -measurement on asymmetric spatial heterodyne technology is introduced, after that a calculating model of relative velocity between spacecraft and navigation target source is established by treating Gaussian emission line as an instance, furthermore, the influence of velocity-measurement precision are made from the way of target source emission line width, frequency point and so on. Finally, as an example, a validation with solar actual lines is implemented by contrast for the aforementioned ways. The research results of this paper would give some theoretical and methodological supports for the establishment of velocity-measurement navigation target source select rules with asymmetric spatial heterodyne technology based on Doppler effect.

关键词： Doppler effect asy mmetric spatial heterody ne velocity-measurement navigation target source Gaussian line influence analysis

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Journal of Intelligent and Connected Vehicles 2022年第1期5卷 1-7页

作者： Qing Xu Keqiang Li Jianqiang Wang Quan Yuan Yanding Yang Wenbo Chu School of Vehicle and Mobility Tsinghua UniversityBeijingChina Dongfeng Automobile Co. Ltd.WuhanChina China Intelligent and Connected Vehicles(Beijing)Research Institute Co. Ltd.BeijingChina

Purpose–The rapid development of Intelligent and Connected Vehicles(ICVs)has boomed a new round of global technological and industrial revolution in recent *** Technology Roadmap of Intelligent and Connected Vehicles(2020)comprehensively analyzes the technical architecture,research status and future trends of *** methodology that supports the roadmap should get ***/methodology/approach–This paper interprets the roadmap from the aspects of strategic significance,technical content and characteristics of the roadmap,and evaluates the impact of the roadmap on researchers,industries and international ***–The technical architecture of ICVs as the“three rows and two columns”structure is studied,the methodology that supported the roadmap is explained with a case study and the influence of key technologies with proposed development routes is ***/value–This paper could help researchers understand both thoughts and methodologies behind the technology roadmap of ICVs.

关键词： Technology roadmap ICVs influence analysis

Index System and influence of Drought in Northwest China

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Chinese Journal of Population,Resources and Environment 2008年第3期6卷 56-62页

作者： Liu Yinge Wen Yanjun Key Lab of Disaster Monitoring and Mechanism Simulating of Shaanxi Province Baoji University of Arts ＆ Sciences Baoji Shaanxi 721013 China

In this paper, the index systems of the agricultural drought and decrease percentage of grain crop are established. The trend and influence of drought in the region is analyzed based on the 50 years （1951-2000） statistical data of precipitation and 52 years （1951 2002） agricultural drought of the region, including tire provinces： Shaanxi, Gansu, Ningxia, Qinghai and Xinjiang. The result shows that the drought disaster is increasing and the most serious were in the 1970s and 1990s, and main agricultural drought is a great disaster incident. The regression prediction equation of drought and flood grades and agricultural drought areas grades are set up by the harmonic wave method, and forecasting the drought will lighten during the first ten years of the 21st century.

关键词： drought index system influence analysis trend prediction

Statistical Diagnostic for Varying-Coefficient Single-Index Models Based on Empirical Likelihood Method

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Journal of Donghua University(English Edition) 2014年第4期31卷 493-496页

作者：王淑玲邓小洪廖大庆 Department of Fundamental Course Air Force Logistics College

Varying-coefficient single-index model( VCSIM) avoids the so-called "curse of dimensionality " and is flexible enough to include several important statistical models. This paper considers statistical diagnosis for VCSIM. First,the parametric estimation equation is established based on empirical likelihood. Then,some diagnosis statistics are defined. At last, an example is given to illustrate all the results.

关键词： varying-coefficient single-index model(VCSIM) empirical likelihood outliers influence analysis

analysis on Relationship between Overcast and Rainy Weather, Drought, Flood and Wheat Yield

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Meteorological and Environmental Research 2011年第9期2卷 47-48,80页

作者： YU Li-jie WANG Xiu-fang LIU Jing-jing Jiyuan Meteorological Bureau in Henan Province Jiyuan 459000China Anyang Meteorological Bureau in Henan Province Anyang 455000China

[Objective] The research aimed to study influence of meteorological factor in late growth stage of wheat. [Method] Based on precipitation, sunshine and yield per unit of wheat in Anyang City in May of 1979-2008, the positive and negative influences of meteorological condition in late growth stage of wheat (May) on wheat yield in Anyang City were analyzed by using agricultural climatic statistical method. Moreover, the reason and defense measure of green-dry hazard in late growth stage of wheat in the city were studied. [Result] When the sunshine percentage in May > 55%, and rainfall 80 mm, and monthly sunshine percentage < 55%, the wheat yield generally reduced. The overcast and rainy weather, flood in late growth stage of wheat were easy to cause green-dry yield reduction. The rainless weather even drought weren’t obviously unfavorable for good harvest of wheat. In May, when precipitation was too more, or duration was too long, and the air humidity was too big, the normal water supply and inorganic nutrient transmission were affected. Meanwhile, when the overcast and rainy weather was longer, the sunshine was shorter, and the sunshine intensity weakened in late stage, it wasn’t favorable for accumulation of photosynthetic product, and the normal implementing of grouting process was affected. The measures should be used to prevent and control green-dry yield reduction of wheat, such as discharging water and preventing flood, breeding good seed, scientific planting and reasonable irrigation. [Conclusion] The research provided scientific basis for studying variety improvement, scientific plantation, reasonable irrigation, good quality and high yield of wheat.

关键词： Wheat yield Meteorological factor Late growth stage influence analysis China

Climate Change and Its influence on Crop Farming in Xintai City

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Meteorological and Environmental Research 2011年第5期2卷 24-27,30页

作者： WANG Yu-he1,WANG Cheng-jun2 1.Xintai Meteorological Bureau in Shandong Province,Xintai 271200,China 2.Laiwu Meteorological Bureau in Shandong Province,Laiwu 271100,China

[Objective] The research aimed to study the variation characteristics of climate and its influence on the crop farming in Xintai City.[Method] By using the yearly and monthly average temperature,rainfall,first and last frost dates,frost-free period,sunshine hours,*** Xintai City during 1957-2009,the variation characteristics of climate and its influence on the crop farming in Xintai City in recent 53 years were analyzed.[Result] The temperature rose in the fluctuation in Xintai *** warm winter phenomenon was prominent,and ≥0℃ accumulated temperature increased *** recent 10 years,the first frost postponed,and the last frost *** growth season of crop *** annual rainfall decreased in the fluctuation,and the annual sunshine hours presented the decrease trend as a *** the accumulated temperature increased,and the frost-free period prolonged,the sowing date and farming system of main crops in Xintai City *** rising of winter temperature was favorable for the development of industrialized agriculture,such as the warm house *** multiple-cropping index improved,and the characteristic planting advantage was *** climate warming made that the planting areas of yellow ginger and day lily enlarged,and the planting boundary moved *** sowing dates of wheat and peanut *** sowing date of yellow ginger advanced,and the growth period ***,the climate variation also made that the plant diseases and insect pests,spring frozen injury aggravated in *** influence of extreme weather induced by the increasing of extreme climate event on the yield and quality of fruit tree was *** planting risks of yellow ginger and day lily increased.[Conclusion] The research provided the scientific basis for promoting the sustainable development of economic society in Xintai.

关键词： Climate change Crop farming influence analysis Xintai City China

influence of Wind Vector Structure Variation of Typhoon "Catfish" Circulation on Its Pathway Mutation

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Meteorological and Environmental Research 2011年第7期2卷 15-18页

作者： WANG Yuan-chao,LIN Bao-ting Yulin Meteorological Bureau in Guangxi,Yulin 537000,China

[Objective] The research aimed to study the wind vector structure variation of No.1013 strong typhoon 'catfish',and its influence on typhoon pathway mutation.[Method] According to the theory that the asymmetric structure of typhoon vortex had influence on typhoon movement,the center of No.1013 super typhoon 'catfish' was as the coordinate origin,and 850,500 hPa tangential rotation speeds within 300-500 km were decomposed into u and v *** composite force movement tendency of typhoon was *** wind vector structure variation of No.1013 strong typhoon 'catfish' and its influence on typhoon pathway mutation were discussed.[Result] At the quick movement stage of No.1013 strong typhoon,the wind vector had obvious asymmetric *** the typhoon rotated in situ,the wind vector presented symmetric *** ΔU,ΔV and composite wind vector had obvious variations,the composite force of typhoon changed,and the moved direction also would *** asymmetric structure of wind speed near 300-500 km around 500 and 850 hPa typhoon centers was favorable for tendency of moved *** pointed directions of ΔU,ΔV and composite wind vector could be as the direction of composite force movement of typhoon.[Conclusion] The research provided reference basis for typhoon prevention.

关键词： Typhoon 'catfish' Wind vector structure Pathway mutation influence analysis China

influence of Climatic Change on Rice Production in Anqing Zone

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Meteorological and Environmental Research 2011年第7期2卷 50-52页

作者： ZOU Shi-jiang1,2,HU Ji-chao1,ZHANG Dou-sheng2,JIANG Xiao-wu3 1.Department of Applied Meteorological Science,Nanjing University of Information Science and Technology,Nanjing 210044,China 2.Zongyang Meteorological Bureau in Anhui Province,Zongyang 246701,China 3.Dingyuan Meteorological Bureau in Anhui Province,Dingyuan 233200,China

[Objective] The research aimed to study the influence of climatic variation on rice production in Anqing zone.[Method] Based on temperature and precipitation data in rice growth period (May-November) during 1980-2009,by using five-year sliding average method,the moving average charts of temperature and rainfall were *** variation characteristics of main factors (temperature and precipitation) which affected rice growth were *** using line moving average simulation method,the climatic yield was separated,and the influence of climatic factor on rice yield in Anqing zone was analyzed.[Result] In recent 30 years,the temperature presented rise trend in rice growth period in Anqing *** from 1993,the rise was *** the rainfall had decline trend,and the rainfall was stable after *** were the climatic background for that rice yield had a wave of quick increase after *** from the separated results of trend yield and meteorological yield,the variation range of relative meteorological yield was big,and the maximum yield reduction reached 27.5%.In recent 30 years,there were four yield reduction *** relationship between meteorological yield of rice and temperature was positive correlation except in *** excessive rainfall in the rice harvest period had unfavorable influence on rice *** drought was the main meteorological agricultural disaster which affected rice yield in the zone.[Conclusion] The research provided the theoretical basis for improving grain yield in Anqing zone.

关键词： Climatic variation Rice production influence analysis Anqing zone China

Case-deletion Diagnostics for Linear Mixed Models

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Case-deletion Diagnostics for Linear Mixed Models