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Improving BDS broadcast ephemeris accuracy using ground-satellite-link observations

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Satellite Navigation 2022年第1期3卷 85-96,I0004页

作者： Junping Chen jungang wang Chao Yu Yize Zhang Bin wang Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Shanghai Key Laboratory of Space Navigation and Positioning Techniques Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China

The BeiDou Navigation Satellite System(BDS)employs a hybrid constellation including GEO(Geosynchronous Earth Orbit),IGSO(Inclined Geosynchronous Orbit),and MEO(Medium Earth Orbit)satellites,where the GEO and IGSO satellites are critical to providing continuous and reliable Positioning,Navigation,and Timing(PNT)services in the Asia–Pacifc region.To handle the inconsistency between the satellite orbits and clocks in the broadcast ephemeris,which are determined by the Orbit Determination and Time Synchronization(ODTS)and the Two-way Satellite Time Frequency Transfer(TWSTFT)technique,respectively,we present the strategies using ground-satellite-link observations to improve the accuracy of broadcast ephemeris.The clock diferences between the ODTS and TWSTFT techniques are used for correcting the radial orbit component to derive the refned orbits,which are used to generate the refned broadcast ephemeris.The test results show the precision of the refned orbits is improved by 50–60%in the 3-h to 12-h predicted arcs for the GEO satellites,and by 40–50%for the IGSO satellites.Moreover,the validation using satellite laser ranging observations shows the mean precision of the refned broadcast ephemeris is improved by 27%compared to the original one.Applying the proposed strategies in the BDS Operational Control Segment(OCS),the time evolution of BDS Single Point Positioning(SPP)in the period from Jan.2016 to April 2021 is evaluated.The SPP accuracy is improved from 1.94,2.06 and 3.29 m to 1.39,1.85,and 2.39 m in the north,east,and up components,respectively.Further update with the inclusion of BDS-3 satellites improve the corresponding SPP precision to 0.68,0.70 and 1.91 m.

关键词： BDS Broadcast ephemeris TWSTFT Orbit determination

Analysis of Electromagnetic Performance of Modulated Coaxial Magnetic Gears Used in Semi-Direct Drive Wind Turbines

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Energy Engineering 2021年第2期118卷 251-264页

作者： jungang wang Liqun Qian Shuairui Xu Ruina Mo School of Mechatronics and Vehicle Engineering East China Jiaotong UniversityNanchang330000China School of Basic Science East China Jiaotong UniversityNanchang330013China

Wind turbine is a key device to realize the utilization of wind energy,and it has been highly valued by all countries.But the mechanical gear transmission of the existing wind power device has the disadvantages of high vibration and noise,high failure rate,and short service time.Magneticfield modulation electromagnetic gear transmission is a new non-contact transmission method.However,the conventional modulation magnetic gear has low torque density and torque defects with largefluctuations.In order to overcome the gear transmis-sion problems of the existing semi-direct drive wind power generation machinery and improve the electromag-netic performance of the traditional magnetic gear transmission,this paper proposes a new transmission scheme of a non-contact semi-direct drive wind generator with a surface mount Halbach array modulated mag-netic gear method,and considers the electromagnetic properties of the semi-direct drive modulation magnetic gear of the wind turbine.Thefinite element software is used to construct the model of the surface-mounted Halbach array magnetic gear and the conventional gear,analyzed the distribution of magneticfield lines of the two magnetic gears,calculated the air gap magneticflux density of the inner and outer air gap,and obtained the main harmonics of the inner and outer air gap magnetic density;calculated the static torque and steady-state operating torque of the inner and outer rotors in the model,compared the air gapflux density,harmonics and torque of the magnetic gears.The simulation results show that the magneticfield modulation type mag-netic gear of the surface mount Halbach array magnetic gear method improves the magnetic induction wave-form of the inner and outer air gap,reduces the pulse torquefluctuation,and has a 60%higher static torque.Applying it to semi-direct drive wind power generation equipment not only overcomes the shortcomings of mechanical gears,but also has higher electromagnetic performance.Therefore,the surface-mounted Halbach array modulated magnetic gear

关键词： Wind power generation gear box magnetic gear finite element analysis

A square root information filter for multi-GNSS real-time precise clock estimation

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Satellite Navigation 2021年第1期2卷 400-413页

作者： Xiang Zuo Xinyuan Jiang Pan Li jungang wang Maorong Ge Harald Schuh Department of Geodesy GeoForschungsZentrum(GFZ)Telegrafenberg14473 PotsdamGermany Institut Für Geodäsie Und Geoinformationstechnik Technische Universität BerlinKaiserin-Augusta-Allee 104-10610553 BerlinGermany.

Real-time satellite orbit and clock estimations are the prerequisite for Global Navigation Satellite System(GNSS)real-time precise positioning services.To meet the high-rate update requirement of satellite clock corrections,the computational efficiency is a key factor and a challenge due to the rapid development of multi-GNSS constellations.The Square Root Information Filter(SRIF)is widely used in real-time GNSS data processing thanks to its high numerical stability and computational efficiency.In real-time clock estimation,the outlier detection and elimination are critical to guarantee the precision and stability of the product but could be time-consuming.In this study,we developed a new quality control procedure including the three standard steps:i.e.,detection,identification,and adaption,for real-time data processing of huge GNSS networks.Effort is made to improve the computational efficiency by optimizing the algorithm to provide only the essential information required in the processing,so that it can be applied in real-time and high-rate estimation of satellite clocks.The processing procedure is implemented in the PANDA(Positioning and Navigation Data Analyst)software package and evaluated in the operational generation of real-time GNSS orbit and clock products.We demonstrated that the new algorithm can efficiently eliminate outliers,and a clock precision of 0.06 ns,0.24 ns,0.06 ns,and 0.11 ns can be achieved for the GPS,GLONASS,Galileo,and BDS-2 IGSO/MEO satellites,respectively.The computation time per epoch is about 2 to 3 s depending on the number of existing outliers.Overall,the algorithm can satisfy the IGS real-time clock estimation in terms of both the computational efficiency and product quality.

关键词： SRIF Precise clock estimation Quality control Real-time GNSS

基于储氨停喷响应特性的SCR系统氨泄漏识别

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内燃机学报 2024年第4期42卷 376-383页

作者：王天田黄自增曾敏任继文王均刚华东交通大学载运工具与装备教育部重点实验室江西南昌330013 江铃汽车股份有限公司动力总成研究院江西南昌330100 得州排放控制技术(无锡)有限公司江苏无锡214037

有效识别出氨(NH_(3))泄漏是柴油机NO_(x)转化(De NO_(x))系统实现精确闭环控制与自适应修正的基础.针对NO_(x)传感器对排气中的NH_(3)和NO_(x)存在交叉敏感这一情况,提出了一种基于停喷状态下选择性催化还原(SCR)系统储氨响应特性的NH_... 详细信息

有效识别出氨(NH_(3))泄漏是柴油机NO_(x)转化(De NO_(x))系统实现精确闭环控制与自适应修正的基础.针对NO_(x)传感器对排气中的NH_(3)和NO_(x)存在交叉敏感这一情况,提出了一种基于停喷状态下选择性催化还原(SCR)系统储氨响应特性的NH_(3)泄漏识别方法.在工况条件合适时,持续将NO_(x)转化效率的传感器测量值和预测值的比值与标定限值进行对比,超过限值时则触发停喷诊断动作,并在停喷过程中通过对比催化器的储氨消耗超过限值的时间与转化效率低于限值的时间先后,实现对NH_(3)泄漏状态的准确识别.结果表明:该方法能够有效识别出SCR系统的NH_(3)泄漏,并能够在NO_(x)排放超过车载故障诊断(OBD)限值时准确识别出NO_(x)排放超标.

关键词：柴油机选择性催化还原系统氨泄漏识别

2种蚜虫取食诱导棉花对棉长管蚜与棉蚜取食行为的影响

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植物保护 2024年第1期50卷 146-151,158页

作者：闫文静朱玉永张玉栋吴娜张全成王俊刚石河子大学农学院石河子832000 新疆生产建设兵团农业技术推广总站乌鲁木齐830011

为研究棉长管蚜Acyrthosiphon gossypii与棉蚜Aphis gossypii对蚜虫取食诱导棉花的取食适应性,揭示取食诱导下两种蚜虫的取食竞争机制,采用刺探电位图谱技术(electrical penetration graph, EPG)测定在健康棉花、棉长管蚜或棉蚜诱导的... 详细信息

为研究棉长管蚜Acyrthosiphon gossypii与棉蚜Aphis gossypii对蚜虫取食诱导棉花的取食适应性,揭示取食诱导下两种蚜虫的取食竞争机制,采用刺探电位图谱技术(electrical penetration graph, EPG)测定在健康棉花、棉长管蚜或棉蚜诱导的棉花上取食6 h的棉长管蚜和棉蚜的16个重要参数,比较两种蚜虫的取食行为。研究发现:1)取食健康棉花时,棉蚜在木质部(G波)的取食持续总时间长于棉长管蚜,棉蚜在木质部的取食能力大于棉长管蚜,但二者在韧皮部的取食能力相差不大。2)取食棉长管蚜诱导的棉花时,棉蚜取食韧皮部(E2波)持续的总时间为(2 531.33±60.86)s,显著大于棉长管蚜E2波持续总时间[(2 196.00±98.91)s];取食棉蚜诱导的棉花时,棉蚜取食韧皮部、木质部持续的总时间显著长于棉长管蚜(P<0.05),说明棉蚜对于棉蚜诱导棉花的取食耐受性大于棉长管蚜。棉蚜对两种蚜虫取食诱导棉花的适应性更强,更易在竞争中取得优势。棉长管蚜与棉蚜取食棉长管蚜或棉蚜诱导棉花的F波持续总时间长于健康棉花,说明经取食诱导的棉花具有一定的抗虫性。

关键词：诱导棉花竞争取食行为寄主植物抗虫性

超声波处理对花生萌发及芽苗中黄酮质量比的影响

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集美大学学报（自然科学版） 2024年第1期29卷 16-23页

作者：许先猛龙圣世朱晴云王俊钢亳州学院生物与食品工程系安徽亳州236800 亳州市天然产物分离纯化工程技术研究中心安徽亳州236800

为促进花生芽苗中黄酮的富集,以‘鲁花1号’花生种子为原料,采用超声波处理方法,研究超声功率、超声温度和超声时间对花生芽苗黄酮的富集作用。结果表明,当超声功率小于200 W时,超声波处理对于花生种子发芽和花生芽苗富集黄酮作用不显著... 详细信息

为促进花生芽苗中黄酮的富集,以‘鲁花1号’花生种子为原料,采用超声波处理方法,研究超声功率、超声温度和超声时间对花生芽苗黄酮的富集作用。结果表明,当超声功率小于200 W时,超声波处理对于花生种子发芽和花生芽苗富集黄酮作用不显著(P>0.05);当超声功率为300 W处理花生种子,花生种子发芽和花生芽苗富集黄酮作用显著增加(P<0.05),但继续增大超声功率,花生芽苗中黄酮质量比又逐渐降低。花生种子经质量分数为0.5%KMnO_(4)消毒后,在超声功率为300 W、超声温度为30℃的条件下处理15 min,然后在30℃条件下用蒸馏水浸种6 h,最后在温度为27℃、相对湿度为(85±5)%的发芽箱中避光培养7 d,花生芽中的黄酮质量比为5.883 mg/g,显著高于对照组的黄酮质量比(P<0.05)。可见,采用适宜温度、短时间、低功率的超声波处理花生种子,可以促进花生种子发芽和花生芽苗黄酮的富集。

关键词：黄酮 ‘鲁花1号’ 花生芽苗超声波富集作用

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模拟数学结合响应面法优化新型鸡肉松的工艺

武汉轻工大学学报 2024年第1期43卷 93-101页

作者：马婉茹丁之恩王俊钢杨续亳州学院生物与食品工程学院亳州236800 安徽农业大学茶与食品学院合肥230000

以鸡胸肉为主要原料,通过煮制、烘烤、炒制等工序处理,将提取的甘草浸提液加入到半成品鸡肉松中从而制备出一款新型风味鸡肉松。以鸡肉松的模糊感官评分为评价指标,根据单因素试验结果,利用Box-Behnken试验设计与响应面分析法相结合的方... 详细信息

以鸡胸肉为主要原料,通过煮制、烘烤、炒制等工序处理,将提取的甘草浸提液加入到半成品鸡肉松中从而制备出一款新型风味鸡肉松。以鸡肉松的模糊感官评分为评价指标,根据单因素试验结果,利用Box-Behnken试验设计与响应面分析法相结合的方法,得到鸡肉松最佳工艺参数。在最优工艺下制成的鸡肉松色泽金黄、无杂质、味道鲜美。对成品鸡肉松进行贮藏期间稳定性研究,结果表明,新型鸡肉松的最优工艺参数为煮制时间55 min,烘烤温度为60℃,甘草浸提液添加量为11%,烘烤时间为34 min。

关键词：鸡肉松模糊数学感官评定响应面优化稳定性

Polyploidization Genetic Mechanism of Sugarcane Genome

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Asian Agricultural Research 2017年第8期9卷 84-87页

作者： jungang wang Tingting ZHAO Benpeng YANG Guoru XIONG Shuzhen ZHANG Sugarcane Research Center of Chinese Academy of Tropical Agricultural Sciences/Institute of Tropical Bioscience and Biotechnology of Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Biology and Genetic Resources of Tropical Crops Ministry of Agriculture

The sugarcane genome polyploidization can reduce the pressure of gene evolution selection,promote the fixation of fine traits,and increase the biomass and economic value of sugarcane.This paper mainly introduced the origin of the sugarcane genome,the chromosome composition,the research progress of polyploidization genetic mechanism,in the hope of providing theoretical reference for sugarcane polyploidization breeding.

关键词： Polyploidization Genome Genetic evolution Molecular mechanism Sugarcane

Study on Acute Toxicity of Purified Protein HAS1 Expression in KM Mice

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Agricultural Biotechnology 2019年第4期8卷 69-71页

作者： Guoru XIONG Gengfeng ZHAO jungang wang Guilan XING Shuzhen ZHANG Institute of Tropical Bioscience and Biotechnology CATAS/Hainan Academy of Tropical Agricultural ResourceCATAS/Sugarcane Research CenterHaikou 571101China College of Basic Medicine and Life Science Hainan Medical CollegeHaikou 571101China Research Center for Drug Safety Evaluation of Hainan Province Haikou 571101China

[Objectives]The antifungal protein HAS1 newly obtained was evaluated for acute toxicity safety in KM mice according to relevant national regulations,so as to eliminate people s concerns about the safety of transgenic plants.[Methods]The acute toxicity of the purified protein HAS1 was observed by intragastric administration of mice,and the poisoning symptoms,poisoning degree,recovery and death were observed.[Results]No abnormal toxicity symptoms were observed in the test group,the vehicle control group and the blank control group.The main tissues and organs were not abnormal in gross anatomy.The average body weight of each group showed an increasing trend compared with before administration at 1,3,7,11 and 14 d after administration.It was found that after giving the purified protein HAS1 to KM mice at a cumulative dose of 64 mg/kg a day,no obvious toxicity was observed in the acute toxicity test,indicating that the test substance was non-toxic by oral administration.[Conclusions]This study provides a basis for further use of the protein and its coding genes.

关键词： Bacillus subtilis HAS Purified protein HAS1 KM mice Toxic reaction