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Results and Analyses of BDS Precise Orbit Determination with the Enhancement of Fengyun-3C

Journal of Geodesy and Geoinformation Science 2019年第3期2卷 68-78页

作者： Tian ZENG Lifen SUI xiaolin jiA Guofeng ji Qinghua ZHANG Information Engineering University Zhengzhou 450001 China State Key Laboratory of Geo-Information Engineering Xi’an 710054 China Xi’an Research Institute of Surveying and Mapping Xi’an 710054 China Chang’an University Xi’an 710054 China PLA University of Science & Technology Nanjing 210007 China

Global navigation satellite system occultation sounder (GNOS) Fengyun-3C was launched successfully on September 23, 2013, which carried GPS/BDS receiver for the first time. This provides the convenience to study the enhancement results of low earth orbiter satellite (LEO) to BDS precise orbit determination (POD). First the data characteristic and code observation noise of GNOS are analyzed. Then the enhancement experiments in the case of global and regional ground observation stations layout are processed with four POD schemes: BDS single system, GPS/BDS double system, BDS single system with GNOS observations, GPS/BDS double system with GNOS observations. The precision of BDS orbits and clocks are compared via overlapping arcs. Results show that in the case of global station layout the along directional precision of GEO satellite has the biggest improvement, with the improvement percentage 60%. Then the precision of cross direction and the along direction of remaining satellites shows the second biggest improvement. The orbit precision of BDS-only POD in part of observation arcs some satellite even suffers a slight decline. The root mean square (RMS) of overlapping clock difference of visible arcs in GPS/BDS POD experiments improves by 0.1 ns level. As to the experiments of regional station layout with 7 ground stations, the orbit and clock overlapping precision and orbit predicting precision are analyzed. Results show that the predicting precision of BDS GEO satellites in the along direction improves by 85%. The remaining also has a substantial improvement, with the average percentage 21.7%. RMS of overlapping clock difference of visible arcs improves by 0.5 ns level.

关键词： BeiDou satellite navigation system LEO precise orbit determination GEO orbit enhancement

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Microecological Prevention and Control Technology of Facility Strawberry Continuous Cropping Diseases and Its Application Effects

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Plant Diseases and Pests 2022年第6期13卷 14-16页

作者： Houjun HE jiexu HUANG xiaolin WANG Yushan QIAO Muxiang ji Jurong Heshan Family Farm Co. Ltd.Jurong 212400China Zhenjiang Institute of Agricultural Sciences in Hilly Areas of jiangsu Jurong 212400China Nanjing Agricultural University Nanjing 212095China

In order to actively develop green ecological strawberry, the authors have studied integrated microecological prevention and control technologies of strawberry continuous cropping diseases, including increasing soil biomass and solar high temperature disinfection during strawberry greenhouse leisure period in summer, biological fertilizer (agent) treatment before colonization, root irrigation treatment with biocontrol agent, as well as appropriate amount of fulvic acid and cytex after colonization, forming a supporting technical system for the microecological prevention and control of soil-borne diseases in facilities. The demonstration application in production shows that the technology has the functions of restoring and enhancing soil biological fertility, enriching beneficial microbial flora, antagonizing harmful bacteria, significantly promoting the growth and development of strawberry, reducing the incidence of soil-borne diseases, reducing the use of chemical fertilizers and pesticides, promoting the early ripening and high yield of strawberry, significantly improving the quality and flavor of strawberry, reducing the risk of pesticide residues, and boosting consumer confidence, which further improves the economic benefit, social benefit and ecological benefit, with good application prospect in production.

关键词： Strawberry Continuous cropping disease Microecology Prevention and control technology

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Improvement in Nutritional Status of Protein-Malnutrition Elderly after Intervention Using a Casein-Based Balanced Liquid Nutrition Formula as Nutritional Support

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Food and Nutrition Sciences 2014年第11期5卷 1083-1093页

作者： Kenji Mizumoto Xudong Xiong Hua Yan xiaolin Wang Zaisi ji Hajime Sasaki Food Science Research Laboratories Meiji Co. Ltd. Odawara Japan Shanghai Meiji Health Science and Technology Inc. Shanghai China Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Shanghai China

A nutritional intervention for 8 weeks was conducted in the elderly (>65 y) living in nursing homes in Shanghai, who showed body weight within the normal range but albumin levels of <35 g/L. The intervened took 400 kcal/day of a balanced liquid nutrition formula containing casein as a major protein source (90% of total protein) in addition to their daily diets, while the non-intervened took only daily diets. Daily diet intakes during the trial were 1738 ± 240 kcal/day in the intervened and 1612 ± 187 kcal/day in the non-intervened. The energy intake in the intervened wascompensated for by reducing their daily diets, which resulted in a similar level to that in the non-intervened. This intervention resulted in intakes of protein and carbohydrate being significantly increased: P16.4%, F27.3%, C56.3% in the intervened;P13.0%, F36.3%, C50.7% in the non-intervened. Albumin level of the intervened increased from 32.7 ± 3.1 g/L to 37.3 ± 1.9 g/L, while it did not significantly change in the non-intervened: 30.0 ± 4.2 g/L to 31.3 ± 4.6 g/L. Using GNRI (geriatric nutritional risk index), nutritional risk levels were assessed;GNRI of the intervened significantly improved from 88.7 ± 6.3 (intermediate risk) to 95.7 ± 4.5 (low risk), while its status did not change in the non-intervened: 84.6 ± 7.7 (intermediate risk) to 86.5 ± 7.9 (intermediate risk). The intervention using a casein-based balanced liquid nutrition formula effectively improved protein-malnutrition in the elderly. This result suggests that a casein-based balanced liquid nutrition formula is an effective nutrition source that can be applied to a nutritional program to improve malnutrition of the elderly.

关键词： Elderly Protein Casein Energy Malnutrition Liquid Nutrition Formula

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The Impact of a Health Forecasting Service on the Visits and Costs in Outpatient and Emergency Departments for COPD Patients--Shanghai Municipality,China,October 2019–April 2020

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China CDC weekly 2021年第23期3卷 495-499页

作者： Xiaofang Ye Zhitao Li Xin Zhou Xiaonan Ruan Tao Lin ji Zhou Dandan Yang Sixu Yang Xiaodan Chen Kang Wu Xiaonan Wang Juzhong Ke xiaolin Liu Li Peng Li Luo Shanghai Key Laboratory of Meteorology and Health Shanghai Meteorological ServiceShanghaiChina Shanghai Typhoon Institute China Meteorological AdministrationShanghaiChina Shanghai Pudong New Area Center for Disease Control and Prevention ShanghaiChina Fudan University Pudong Institute of Preventive Medicine ShanghaiChina School of Public Health Fudan UniversityShanghaiChina

What is already known on this topic?The morbidity and mortality of chronic obstructive pulmonary disease(COPD)is associated with adverse weather and air ***,COPD patients are not able to be alerted in advance of high risk *** is added by this report?This prospective controlled trial conducted in Pudong New Area of Shanghai from October 2019 to April 2020 provided evidence of COPD risk forecasting service on the reductions in visits and costs of COPD patients in outpatient and emergency departments in China for the first *** are the implications for public health practice?This study suggests that COPD risk forecasting service could be integrated into existing COPD management in public health to improve the health and economic outcomes.

关键词： mortality forecasting service

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高含硫天然气过滤单元性能优化

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天然气工业 2016年第3期36卷 87-92页

作者：刘震姬忠礼吴小林赵峰霆中国石油大学(北京)机械与储运工程学院过程流体过滤与分离技术北京市重点实验室中国石油大学(北京)化学工程学院

为了避免高含硫天然气湿气输送过程中所夹带的固体颗粒和液体杂质对天然气净化装置和效果的不良影响,在脱硫工艺前端设置了由预过滤器和聚结过滤器所组成的两级过滤单元。针对某高含硫天然气净化厂原料气过滤单元存在的聚结过滤器滤芯... 详细信息

为了避免高含硫天然气湿气输送过程中所夹带的固体颗粒和液体杂质对天然气净化装置和效果的不良影响,在脱硫工艺前端设置了由预过滤器和聚结过滤器所组成的两级过滤单元。针对某高含硫天然气净化厂原料气过滤单元存在的聚结过滤器滤芯压降不上升、无法通过压降来判断滤芯更换时间等问题,利用两级过滤性能评价系统对比了不同过滤性能预过滤器滤芯和聚结过滤器滤芯组合的过滤性能,发现其原因在于聚结过滤器滤芯对亚微米级液滴的聚结性能不理想、预过滤器滤芯和聚结过滤器滤芯的性能不匹配。为此,提出了改进措施:①改进聚结过滤器滤芯的聚结层;②设置疏油型排液层,改变预过滤器滤芯的结构参数,使之与改进后的聚结过滤器滤芯的性能相匹配。实验结果表明:改进后聚结过滤器滤芯的稳态压降较在用滤芯降低75%,对于粒径为0.3μm及以上的液滴过滤效率达到99.99%,同时实现了预过滤器滤芯和聚结过滤器滤芯压降的同步变化。现场试验结果表明:改进后的原料气过滤单元对液体杂质的过滤能力提高了1倍,能更有效地保证后续工艺的安全运行。该研究成果为高含硫天然气过滤元件设计和过滤系统优化运行提供了参考。

关键词：高含硫天然气脱硫预过滤聚结过滤固体颗粒液体杂质滤芯压降性能匹配

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Orbits quality and PPP application for Galileo

Orbits quality and PPP application for Galileo

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第九届中国卫星导航学术年会

作者： Guofeng ji Hang Chang Zhiqiang Yang xiaolin jia Liang Zhang College of Geology Engineering and Geomantics Chang'an University National key laboratory of Geographic information Engineering Xi'an Research Institute of Surveying and Mapping

The orbit quality and PPP application of the Galileo precise products from five MGEX analysis centers(AC) are analyzed in this article, the influence of Solar Radial Pressure(SRP) model on Precise Orbit Determination(POD) is studied. The results show that: the quality of Galileo orbit from GFZ and TUM is significantly improved if the Cuboid Box-Wing(CBW) priori model is used. The SLR residual amplitudes reduced from 20 cm down to 10 cm, the STD has decreased about 50%, and the mean SLR bias is reduced from-2.06.0 cm to millimeters level;and PHMs clock-offsets daily linear fitting results also show that the periodic signature could be significantly reduced, which is consistent with the results of SLR residuals. CODE’s ECOM2 model shows slightly worse performance than CBW+ECOM1 model, but much better than classic ECOM1 model. In addition, the mean SLR bias of CODE’s and WHU’s orbits is about-2.04.0 cm, too larger than the result of other Analysis Center, so that the impact of albedo model and antenna thrust require appropriate consideration. Precise point positioning(PPP) error of Galileo-only is about 1.0 cm in horizontal, which is very close to the results of GPS-only, but larger than 3.0 cm in vertical component due to the limited number of active satellites. The convergence speed of GPS/Galileo combined solution is faster than any single system, the positioning accuracy in horizontal is improved respect to GPS-only, but a small degradation can be observed in vertical component.

关键词： Galileo system Precise Orbit determination SLR residuals Solar Radiation model PPP

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Unstructured Road Detection Based on Region Growing

Unstructured Road Detection Based on Region Growing

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第30届中国控制与决策会议

作者： Li xiaolin ji Yufeng Gao Yan Feng Xiaoxue Li Weixing School of Automation Beijing Institute of Technology

Image based road detection is a vital and challenging task in many real-world applications such as autonomous driving,road departure *** this paper,we study the problem of unstructured road detection from a color *** algorithm we propose decomposes the road detection into three steps:the estimation of the horizon line by similarity measurement,followed by the road area prediction based upon the estimated horizon line,and region growing to segment the image into road and non-road *** road area prediction provides good road *** region growing is effective to detect the road region utilizing the feature extracted from the road *** results demonstrate that the proposed algorithm is accurate and efficient.

关键词： Unstructured road detection Horizon line estimation Road area prediction Region growing

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流量控制式ECHPS系统转阀结构参数优化设计

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农业机械学报 2008年第11期39卷 26-29,47页

作者：郭晓林季学武陈奎元装甲兵工程学院机械工程系清华大学清华大学汽车工程系

在流量控制式电控液压助力转向系统(ECHPS)中,转阀结构参数对系统的可变助力特性有重要的影响。应用液阻网络理论对系统的等效通流面积和助力特性进行了分析。建立了转阀阀口通流面积与转阀主要结构设计参数(小坡口宽度、小坡口圆弧偏... 详细信息

在流量控制式电控液压助力转向系统(ECHPS)中,转阀结构参数对系统的可变助力特性有重要的影响。应用液阻网络理论对系统的等效通流面积和助力特性进行了分析。建立了转阀阀口通流面积与转阀主要结构设计参数(小坡口宽度、小坡口圆弧偏心距、阀芯键宽、小坡口轴向长度)之间的数学关系。对转阀的主要结构参数进行了优化设计,优化前为0.9mm、10mm、5.76mm和11mm,优化后为1.115mm、4.626mm、5.652mm和4.499mm。仿真计算结果表明优化后可变助力特性范围由1.2升为3,低速转向时最大手力达到了4N.m。

关键词：电控液压助力转向转阀助力特性优化

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基于响应面法的折流板除雾器分离性能优化

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过程工程学报 2018年第4期18卷 689-696页

作者：马巍威吴小林姬忠礼中国石油大学(北京)化学工程学院北京102249 中国石油大学北京机械与储运工程学院北京102249 过程流体过滤与分离技术北京市重点实验室北京102249

用响应面分析法分析不同排液结构对新式异型折流板除雾器气液分离性能的影响,并对排液结构参数进行优化设计.通过单因素实验对比筛选对除雾器性能具有显著影响的关键参数,用中心复合设计实验建立响应面多元回归模型,分析影响除雾器性能... 详细信息

用响应面分析法分析不同排液结构对新式异型折流板除雾器气液分离性能的影响,并对排液结构参数进行优化设计.通过单因素实验对比筛选对除雾器性能具有显著影响的关键参数,用中心复合设计实验建立响应面多元回归模型,分析影响除雾器性能系数的参数间交互作用,得出最优参数.结果表明,影响除雾器性能参数的最优取值为分离气速2.6 m/s、排液钩高度7.3mm、前置排液槽和后置排液槽宽度分别为3.1和2.3 mm.优化的折流板除雾器性能系数计算值为2.073,实验值为1.875,优化结果较可靠.

关键词：折流板除雾器响应面法分离性能性能系数优化设计

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基于余弦相似度反向策略的自然计算方法

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信息与控制 2022年第6期51卷 708-718页

作者：孙小琳季伟东王旭哈尔滨师范大学大学计算机科学与信息工程学院黑龙江哈尔滨150025

现有的基于反向策略的优化算法大多根据初始种群适应度值大小进行反向择优,没有充分考虑迭代过程中的反向且存在收敛速度慢的问题。针对此问题,提出一种基于余弦相似度反向策略的快速收敛自然计算方法,通过计算每个粒子与区域中心粒子... 详细信息

现有的基于反向策略的优化算法大多根据初始种群适应度值大小进行反向择优,没有充分考虑迭代过程中的反向且存在收敛速度慢的问题。针对此问题,提出一种基于余弦相似度反向策略的快速收敛自然计算方法,通过计算每个粒子与区域中心粒子的余弦相似度,将粒子划分为相似子群与非相似子群,对非相似子群按照相似程度进行加权反向,进而加快收敛速度,同时引入柯西扰动提高种群多样性。将该策略应用到三种不同的自然计算方法中,对收敛性进行分析,并采用12个经典测试函数验证其性能,对实验数据进行非参数检验。分析结果表明,应用余弦相似度反向策略的方法在大多数测试函数上表现优异,说明提出的方法具有很好的普适性和有效性。

关键词：自然计算快速收敛余弦相似度加权反向

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