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| 1 | Barometric altimetry system as virtual constellation applied in CAPS显示文摘This work describes the barometric altimetry as virtual constellation applied to the Chinese Area Positioning System (CAPS), which uses the transponders of communication satellites to transfer navigation messages to users. Barometric altimetry depends on the relationship of air pressure varying with altitude in the Earth’s atmosphere. Once the air pressure at a location is measured the site altitude can be found. This method is able to enhance and improve the availability of three-dimensional positioning. The difficulty is that the relation between barometric pressure and altitude is variable in different areas and under various weather conditions. Hence, in order to obtain higher accuracy, we need to acquire the real-time air pressure corresponding to an altimetric region’s reference height. On the other hand, the altimetry method will be applied to satellite navigation system, but the greatest difficulty lies in how to get the real-time air pressure value at the reference height in the broad areas overlaid by satellite navigation. We propose an innovational method to solve this problem. It is to collect the real-time air pressures and temperatures of the 1860 known-altitude weather observatories over China and around via satellite communication and to carry out time extrapolation forecast uniformly. To reduce data quantity, we first partition the data and encode them and then broadcast these information via navigation message to CAPS users’ receivers. Upon the interpolations being done in receivers, the reference air pressure and temperature at the receiver’s nearby place is derived. Lastly, combing with the receiver-observed real air pressure and temperature, the site’s altitude can be determined. The work is presented in the following aspects: the calculation principle, formulae, data collection, encoding, prediction, interpolation method, navigation message transmission together with errors causes and analyses. The advantages and shortcomings of the technique are discussed at the end. | AI GuoXiang SHENG PeiXuan DU JinLin ZHENG YongGuang CAI XianDe WU HaiTao HU YongHui HUA Yu LI XiaoHui | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，3： | 22 |
| 2 | 川西亚高山针叶林土壤硝化作用及其影响因素显示文摘采用BarometricProcessSeparation(BaPS)技术对川西亚高山针叶林土壤总硝化作用速率的季节动态进行了研究,并分析了各影响因素与总硝化速率的关系.通过土壤温度和水分含量的控制实验,对温度和水分含量与总硝化速率之间的关系进行了一次线性和曲线模拟.结果表明,6至10月各月份之间的总硝化速率存在显著差异(P<0.01),在7月总硝化速率达到最大值;土壤温度和水分含量与总硝化速率显著正相关(P<0.05),对总硝化速率的影响存在明显的交互作用,水分含量可能对总硝化速率的影响更大,在季节变化中温度和水分含量可能对硝化过程产生直接和间接两种作用;pH值与总硝化速率之间的相关性不明显;森林凋落量与总硝化速率间没有显著相关性,但若仅考虑6至9月,森林凋落量与总硝化速率极显著相关(P<0.01).总之,土壤温度和水分含量很可能是影响总硝化速率的两个最主要的因素. | 刘义 陈劲松 尹华军 刘庆 林波 | 2006 | 应用与环境生物学报2006，12，4： | 11 |
| 3 | Interpolation Fitting Algorithm in Time-Space Domain of Differential Barometric Altimetry显示文摘In order to overcome the limitations of a unitary reference station in mobile communication positioning network differential barometric altimetry(DBA)and broaden the action scope of the reference station and improve positioning accuracy of elevation,an integrated interpolation algorithm model based on generalized extended approximation(GEA)algorithm and Kriging interpolation in time-space domain of reference station is proposed.In the time domain,barometric measured data is considered the maximum value estimated by bilateral extension to avoid wrong direction of estimation,which is approaching true value.In the spatial domain,barometric relevance among multiple reference stations is utilized,the weighted coefficients of multiple reference stations is calculated by the integrated algorithm model based on the GEA algorithm and Kriging interpolation.The impact of each reference station to the measured station is quantified,so that a virtual reference station is constructed,which can overcome the limitation of barometric correction by a unitary reference station.In addition,the measurement error due to irregular change in atmospheric pressure will be eliminated. | Zhengqun Hu Lirong Zhang Guanyi Ma Yuanfa Ji | 2019 | Journal of Beijing Institute of Technology2019，28，1： | 1 |
| 4 | Tiny insects against the weather flight and foraging patterns of Frankliniella schultzei (Thripidae) not altered by onset of rainfall显示文摘To survive in nature,organisms may need to take direct action to mitigate specific dangers from their environmental surroundings.Tiny flying insects are thought to be at particular risk from rainfall that would be of negligible concern to larger animals.The study species Frankliniella schultzei is a thrips that inhabits flowers and feeds mostly on petal tissue and pollen.While found to respond in the laboratory to decreases in atmospheric pressure associated with cyclonic conditions (rather than merely heavy rainfall),their responses to conditions preceding rainfall have not been tested in the field.Initial field sampling investigated the relationship between floral development and sites at which male,female,and larval thrips were generally present on sunny days.We then designed a sampling strategy to test if these thrips can anticipate imminent rainfall or storms and so seek shelter deep within flowers,by sampling host flowers (in sections)on multiple days with different weather conditions.Sticky traps were used to intercept thrips in flight,thus providing a measure of flight behavior across different days.The initial sampling found adult thrips primarily at the petal apex of anthesis-stage flowers where pollen is distributed. We subsequently found that rainfall,atmospheric pressure change,temperature,humidity and wind had no effect on flight behavior of E schultzei,or on their positions within flowers.These findings suggest rainfall is not a serious hazard for them.Perhaps thrips can survive raindrop collisions during flight,as impacts with water droplets are not expected to break the surface tension. | Lachlan C.Jones Brodie J.Foster Michelle A.Rafter Gimme H.Walter | 2018 | Insect Science2018，25，6： | 0 |
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