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基于角速度信息先验的固定无源单站直接定位方法

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电子学报 2024年第7期52卷 2190-2200页

作者：陈梁栋黄知涛王翔吴癸周国防科技大学电子科学学院湖南长沙410073 中国人民解放军95438部队四川眉山620860

针对传统两步定位法在固定无源单站定位精度不高的问题,提出一种基于角速度先验的固定无源单站直接定位方法 .首先,给出定位场景及辐射源运动模型,根据雷达辐射源脉内、脉间以及空间采样特点,按照快时间、慢时间、快拍构建三维观测信号... 详细信息

针对传统两步定位法在固定无源单站定位精度不高的问题,提出一种基于角速度先验的固定无源单站直接定位方法 .首先,给出定位场景及辐射源运动模型,根据雷达辐射源脉内、脉间以及空间采样特点,按照快时间、慢时间、快拍构建三维观测信号模型.将快时间变换至频域并提取一组最强信号,利用本文提出的空时对称自相关函数(Space Time Symmetric Autocorrelation Function,STSAF),消除影响定位精度的多余相位项;然后,将经上述处理的2次观测信号进行混频,构建定位模型并给出直接定位代价函数;同时,针对性提出一种基于位置选择的MUSIC(MUltiple SIgnal Classification)算法,根据慢时间域包含的距离信息及空间域包含的方位信息,对辐射源横、纵坐标进行搜索,实现对辐射源的直接定位.本文对算法计算复杂度和克拉美罗下界(Cramer-Rao Lower Bound,CRLB)进行了理论推导,分析了影响定位精度的因素,对比所提直接定位方法与传统两步定位法的均方根误差,绘制本文方法的GDOP(Geometric Dilution Of Precision)曲线.

关键词：固定无源单站直接定位 STSAF函数位置选择MUSIC算法

穿心莲不同生长发育期穿心莲内酯积累与碳氮代谢特征

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西南农业学报 2024年第5期37卷 1038-1046页

作者：简少芬钟楚万斯林杨陈东亮广西壮族自治区药用植物国家中医药传承创新中心/广西药用资源保护与遗传改良重点实验室/广西中药资源智慧创制工程研究中心南宁530023 广西农业科学院经济作物研究所南宁530007

【目的】明确穿心莲(Andrographis paniculata)不同生长发育期主要活性成分穿心莲内酯的积累和碳、氮代谢特征及其关系,为穿心莲优质高产栽培管理提供理论依据。【方法】根据穿心莲生长发育特点,将其物候期划分为塔型期、团棵期、拔节... 详细信息

【目的】明确穿心莲(Andrographis paniculata)不同生长发育期主要活性成分穿心莲内酯的积累和碳、氮代谢特征及其关系,为穿心莲优质高产栽培管理提供理论依据。【方法】根据穿心莲生长发育特点,将其物候期划分为塔型期、团棵期、拔节期、现蕾期、盛花期和花果期,分析大田条件下各生长发育期的生物量及穿心莲内酯积累和碳、氮代谢特征。【结果】穿心莲全株和茎秆生物量在盛花期开始稳定,叶片生物量在拔节期开始趋于稳定,相对生长速率和叶片生物量占比随着生长进程逐渐下降。叶片的穿心莲内酯含量在塔型期至现蕾期(营养生长期)逐渐上升,在现蕾期达峰值且保持稳定,单株穿心莲内酯产量在盛花期达最大。穿心莲内酯合成关键酶基因ApDXS、ApDXR、ApGGPS和ApCPS的表达量在团棵期上升,随后下降并趋于平稳,而基因ApHMGS和ApHMGR1在现蕾期后维持在高表达水平。穿心莲内酯合成可能主要受甲羟戊酸(MEP)途径调控,且穿心莲内酯积累滞后于基因表达。叶片和茎秆的氮含量随着穿心莲的生长进程逐渐下降,植株地上部氮积累量和茎秆氮积累量在现蕾期达最大值,而叶片的氮在现蕾期后向果实转移其积累量逐渐下降。塔型期和团棵期叶片氮同化相关酶中的谷氨酰胺合成酶(GS)、谷氨酸脱氢酶(NAD-GDH)和异柠檬酸脱氢酶(ICDH)活性较高,同时叶片蔗糖和可溶性总糖含量也较高,随后氮同化酶活性及蔗糖和可溶性总糖含量下降,淀粉含量的变化则相反。叶片穿心莲内酯含量和单株穿心莲内酯产量与株高、生物量、地上部氮积累量和淀粉含量呈极显著正相关(P<0.01,下同),与叶片氮含量呈极显著负相关,说明促进穿心莲营养生长期生物量积累有利于提高穿心莲内酯含量和产量。【结论】现蕾期至盛花期是采收穿心莲药材的最佳时期;营养生长期是穿心莲氮同化和积累的主要时期,在该时期适当增施氮肥促进穿心莲生物量积累可提高穿心莲内酯含量和产量。

关键词：穿心莲生育时期碳氮代谢穿心莲内酯

广西野生大豆种质资源青贮饲用品质综合评价与筛选

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南方农业学报 2024年第5期55卷 1284-1295页

作者：陈东亮谭玉荣杨守臻唐向民曾维英孙祖东广西农业科学院经济作物研究所广西南宁530007

【目的】对广西野生大豆种质资源青贮饲用品质进行综合评价,筛选出青贮饲用品质优异的野生大豆种质资源,为青贮饲用大豆品种的选育及其饲用品质的遗传改良提供原始遗传材料。【方法】以94份广西野生大豆种质为供试材料,鼓粒期(R6)全株... 详细信息

【目的】对广西野生大豆种质资源青贮饲用品质进行综合评价,筛选出青贮饲用品质优异的野生大豆种质资源,为青贮饲用大豆品种的选育及其饲用品质的遗传改良提供原始遗传材料。【方法】以94份广西野生大豆种质为供试材料,鼓粒期(R6)全株刈割后测定其饲用品质指标,对其进行相关分析和聚类分析,并采用隶属函数分析法、主成分分析法及隶属函数结合主成分分析法评价供试材料的青贮饲用品质,筛选出优异野生大豆种质。【结果】粗蛋白(CP)与粗脂肪(CF)呈极显著负相关(P<0.01,下同),与中性洗涤纤维(NDF)呈显著负相关(P<0.05),与相对饲喂价值(RFV)、干物质采食量(DMI)和相对饲草品质(RFQ)呈极显著正相关,表明选择高CP、高RFV、高可消化总养分(TDN)及高RFQ野生大豆种质的同时也会筛选出CF和NDF含量低的种质。系统聚类结果显示,在欧氏距离为20时,94份野生大豆被分为四大类,其中第Ⅱ类群包括9份种质,主要来源于桂林市全州县和兴安县,其主要特征为CP含量(平均值22.98%)、RFV(平均值133.26)、TDN(平均值58.10)、RFQ(平均值127.41)等饲用品质正向指标较高,CF含量(平均值21.39%)、ADF含量(平均值32.31%)、NDF含量(平均值44.51%)等饲用品质负向指标含量较低,是饲用品质优异种质类群。将隶属函数分析法、主成分分析法及隶属函数结合主成分分析法的3种评价结果进行对比,筛选出GXYSD33、GXYSD10、GXYSD43、GXYSD48等10份综合或单一品质性状优异的青贮饲用野生大豆种质资源,其中GXYSD33为青贮饲用品质特优种质,其CP含量(28.28%)、RFV(141.84)、RFQ(136.07)和TDN(61.83)等饲用品质正向指标均居供试种质之首。【结论】基于野生大豆青贮饲用品质性状间的显著和极显著相关性可实现多性状同步改良。筛选出的10份青贮饲用品质优异的野生大豆种质资源可作为青贮饲用大豆品种选育及其饲用品质遗传改良的理想遗传材料。

关键词：野生大豆青贮饲料饲用品质综合评价筛选

W-Cu复合材料的应用现状及掺杂改性的研究进展

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稀有金属与硬质合金 2024年第1期52卷 6-16页

作者：娄文鹏李秀青魏世忠王琪梁菁琨陈良栋徐流杰河南科技大学材料科学与工程学院河南洛阳471023 金属材料磨损控制与成型技术国家地方联合研究中心河南洛阳471023 河南省高温难熔金属材料国际联合实验室河南洛阳471023

W-Cu复合材料因具有高的硬度、耐磨性、抗烧蚀性能、导电性和导热性以及低热膨胀系数等综合性能而被广泛应用于多种工业领域。本文介绍了W-Cu复合材料的最新研究进展及其在电触头、微电子、军事、功能梯度材料方面的应用现状,着重总结... 详细信息

W-Cu复合材料因具有高的硬度、耐磨性、抗烧蚀性能、导电性和导热性以及低热膨胀系数等综合性能而被广泛应用于多种工业领域。本文介绍了W-Cu复合材料的最新研究进展及其在电触头、微电子、军事、功能梯度材料方面的应用现状,着重总结和分析了目前W-Cu复合材料掺杂改性的分类及原理,以及掺杂改性对材料性能的影响,最后提出了W-Cu复合材料未来发展的潜在问题和值得关注的研究方向。

关键词： W-Cu复合材料掺杂改性钨铜互溶性应用现状性能

Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

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Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： Yan liang Song chen Xin dong Tu Liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor ***,the construction of the fingerprint database is quite *** when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is *** appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)*** this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization *** points(RPs)are generated in the grid by the FGGC ***,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex *** a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous *** proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy *** mean error of the proposed model is 0.36 m,far lower than that of previous ***,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor *** also shows high-accuracy performance with a fast running speed even under a large-size *** results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)

A visual modeling method for spatiotemporal and multidimensional features in epidemiological analysis:Applied COVID-19 aggregated datasets

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Computational Visual Media 2024年第1期10卷 161-186页

作者： Yu dong Christy Jie liang Yi chen Jie Hua School of Computer Science University of Technology SydneySydneyNSW2007Australia Beijing Key Laboratory of Big Data Technology for Food Safety Beijing Technology and Business UniversityBeijing100048China

The visual modeling method enables flexible interactions with rich graphical depictions of data and supports the exploration of the complexities of epidemiological ***,most epidemiology visualizations do not support the combined analysis of objective factors that might influence the transmission situation,resulting in a lack of quantitative and qualitative *** address this issue,we developed a portrait-based visual modeling method called+*** method considers the spatiotemporal features of virus transmission patterns and multidimensional features of objective risk factors in communities,enabling portrait-based exploration and comparison in epidemiological *** applied+msRNAer to aggregate COVID-19-related datasets in New South Wales,Australia,combining COVID-19 case number trends,geo-information,intervention events,and expert-supervised risk factors extracted from local government area-based *** perfected the+msRNAer workflow with collaborative views and evaluated its feasibility,effectiveness,and usefulness through one user study and three subject-driven case *** feedback from experts indicates that+msRNAer provides a general understanding for analyzing comprehension that not only compares relationships between cases in time-varying and risk factors through portraits but also supports navigation in fundamental geographical,timeline,and other factor *** adopting interactions,experts discovered functional and practical implications for potential patterns of long-standing community factors regarding the vulnerability faced by the *** confirmed that+msRNAer is expected to deliver visual modeling benefits with spatiotemporal and multidimensional features in other epidemiological analysis scenarios.

关键词： visual modeling epidemiological analysis spatiotemporal multidimensional COVID-19

In situ XAFS Investigation on Zincblende ZnS up to 31.7 GPa

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Chinese Physics Letters 2013年第4期30卷 129-132页

作者： YANG Jun ZHU Feng ZHANG Qian WU Ye WU Xiang QIN Shan dong Jun-Cai chen dong-liang Key Laboratory of Orogenic Belts and Crustal Evolution(Ministry of Education and School of Earth and Space SciencesPeking UniversityBeijing 100871 Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049

In situ high-pressure x-ray absorption fine structure(EXAFS)measurements on the Zn K-edge in zincblende ZnS are performed up to 31.7 GPa at room temperature using a synchrotron radiation x-ray re-focused by a polycapillary half-lens in the classic energy-scanning transmission *** present XAFS data illustrate that ZnS undergoes a phase transition from zincblende F43m to rocksalt Fm3m at 16.9 GPa,accompanied by the increase of the first shell coordination number of the absorption zinc atoms and the unit-cell volume collapse of~14%.The isothermal equation of state of the F43m ZnS is well presented by the third-order Birch–Murnaghan equation of state with V0=158.6±0.8?3,B0=87±5 GPa and B0'=4(fixed).The high-pressure behavior of ZnS from the XAFS spectra is consistent with the previous high-pressure XRD *** addition,the present experimental method demonstrates that the large divergent x-ray micro-beam induced by a polycapillary half-lens can suppress effectively the glitches from single crystal diamond anvil and improve significantly the quality of the XAFS data,which will shed light on the high-pressure XAFS applications.

关键词： XAFS absorption capillary

Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： liang-liang dong Yu-Lin Zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

Analysis and Modeling of Time Output Characteristics for Distributed Photovoltaic and Energy Storage

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Energy Engineering 2024年第4期121卷 933-949页

作者： Kaicheng Liu chen liang Xiaoyang dong Liping Liu China Electric Power Research Institute Beijing100192China Electric Power Research Institute State Grid Gansu Electric Power CompanyLanzhou730000China State Key Laboratory of Power Grid Safety Beijing100084China

Due to the unpredictable output characteristics of distributed photovoltaics,their integration into the grid can lead to voltage fluctuations within the regional power ***,the development of spatial-temporal coordination and optimization control methods for distributed photovoltaics and energy storage systems is of utmost importance in various *** paper approaches the issue from the perspective of spatiotemporal forecasting of distributed photovoltaic(PV)generation and proposes a Temporal Convolutional-Long Short-Term Memory prediction model that combines Temporal Convolutional Networks(TCN)and Long Short-Term Memory(LSTM).To begin with,an analysis of the spatiotemporal distribution patterns of PV generation is conducted,and outlier data is handled using the 3σ ***,a novel approach that combines temporal convolution and LSTM networks is introduced,with TCN extracting spatial features and LSTM capturing temporal ***,a real spatiotemporal dataset from Gansu,China,is established to compare the performance of the proposed network against other *** results demonstrate that the model presented in this paper exhibits the highest predictive accuracy,with a single-step Mean Absolute Error(MAE)of 1.782 and an average Root Mean Square Error(RMSE)of 3.72 for multi-step predictions.

关键词： Photovoltaic power generation spatio-temporal prediction temporal convolutional network long short-term memory network