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Joint space-time interference suppression method of GNSS receiver based on the maximum CNR criterion

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Joint space-time interference suppression method of GNSS rec...

Co-Seismic Surface Rupture and Recurrence Interval of Large Earthquakes along Damaoyaba-Litang Segment of the Litang Fault on the Eastern Margin of the Tibetan Plateau in China

第五届中国卫星导航学术年会

作者： Guo Yi Yang Sheng Shen rongjun Beijing Satellite Navigation Center School of Automation Science and Electrical Engineering of Beijing University of Aeronautics and Astronautics

ISBN: (纸本)9783642547362

Joint space-time adaptive process（STAP） is an advanced interference suppression method for GNSS receiver. The STAP method based on power inversion（PI） and beam forming（BF） optimal criterion is widely used. We usually hope that anti-jamming processing not only null the interference direction, but also beam forming the satellite signal for antenna array processing gain. But satellite signal is too weak to hardly estimation the direction of arrive（DOA）, and the estimation error cause anti-jamming performance drop quickly. Aim at this problem, a joint space-time anti-jamming method based on Maximum CNR criterion is proposed. Firstly, we use PI method to suppress interference primarily, and acquisition and tracking to get the desired code spread signal, and estimate the satellite signal direction vector. Then we compare the output CNR of PI and BF method, control the output to maximum the CNR of output signal. The proposed method not only avoid the complexity of traditional satellite DOA estimation, but also overcome the performance loss by the estimation error. The performance is much better than PI and BF method and the complexity is simple, it is benefit for engineer realization.

关键词： space‐time interference suppression power inversion beam forming carrier to noise ratio

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Journal of Earth Science 2021年第5期32卷 1139-1151页

作者： Shiyuan Wang rongjun Zhou Mingjian Liang Shao Liu Nina Liu Jianyu Long Sichuan Earthquake Agency^Chengdu 610041 China School of Geological Engineering and Geomatics Chang'an UniversityXi'an 710054China

The Litang fault is a left-lateral secondary shear zone in the Sichuan-Yunnan active block that accommodates the tectonic deformation associated with the eastward extrusion of the upper crust of the Tibetan Plateau. Based on 1 : 50 000 geological mapping of active faults, the Litang fault consists of three geometric segments, the Cuopuhu, Damaoyaba, and Litang segments, in the west of Litang, which are divided by the of Haizi Mountain uplift and the wide-angle bending and branching of the fault near Jinchanggou. This study also identifies the surface rupture of the A.D. 1890 earthquake, which is distributed intermittently along the ~28 km long Damaoyaba segments and ~25 km long Litang segments. The maximum horizontal displacement is 4.1 m along Damaoyaba segments, and 4 m along Litang segments. The rupture involves typical left-lateral shear movement. The two ruptures are divided by discontinuous segments or gaps that are ~18 km long;thus, the total surface rupture is approximately 71 km long. The estimated moment magnitude was M_(w)7.3±0.1. A comprehensive analysis of data obtained from 5 trenches excavated along the Damaoyaba and Litang segments and the trench data by Xu et al.(2005) identifies age constraints of the 4 most recent paleoseimic events occurred B.C. 1468±54–1340±25, B.C. 52±25–A.D. 76±47, A.D. 1115±90, and A.D. 1890, respectively. The recurrence intervals are 1 415±80, 1 104±104, and 775±90 a, which are consistent with quasi-periodic earthquake recurrence behavior. The average recurrence interval is 1 098±112 a.

关键词： Litang fault surface rupture active fault recurrence intervals paleoearthquake eastern Tibetan Plateau

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Modelling of Level Fluctuation in Continuous Casting

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Journal of Materials Science & Technology 2003年第z1期19卷 158-160页

作者： Xiao LIU Huanxin ZHANG rongjun XU Yongquan LI Houfa SHEN Baicheng LIU Baoshan Iron and Steel Co. LTD. Shanghai 201900 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Baoshan Iron and Steel Co. LTD. Shanghai 201900 China Baoshan Iron and Steel Co. LTD. Shanghai 201900 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

The free surface profile and fluid flow in the mold of continuous casting have been calculated by the VOF method couplingthe SIMPLER algorithm. The SIMPLER-VOF model developed is validated by solving a classical experiment, broken damproblem. The calculated surface profile is consistent with water modelling. It is found that the free surface profile is coherentlyrelated to the position of circumfluence in the mold of continuous casting. With the increase of nozzle port inclination, thepositive vortex above the jet is near to the meniscus and the level fluctuation becomes prominent.

关键词： Level fluctuation, Fluid flow, Continuous casting, Numerical simulation

Sentiment Analysis Using E-Commerce Review Keyword-Generated Image with a Hybrid Machine Learning-Based Model

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Computers, Materials & Continua 2024年第7期80卷 1581-1599页

作者： Jiawen Li Yuesheng Huang Yayi Lu Leijun Wang Yongqi Ren rongjun Chen School of Computer Science Guangdong Polytechnic Normal UniversityGuangzhou510665China Hubei Province Key Laboratory of Occupational Hazard Identification and Control Wuhan University of Science and TechnologyWuhan430065China

In the context of the accelerated pace of daily life and the development of e-commerce,online shopping is a mainstreamway for consumers to access products and *** understand their emotional expressions in facing different shopping experience scenarios,this paper presents a sentiment analysis method that combines the ecommerce reviewkeyword-generated imagewith a hybrid machine learning-basedmodel,inwhich theWord2Vec-TextRank is used to extract keywords that act as the inputs for generating the related images by generative Artificial Intelligence(AI).Subsequently,a hybrid Convolutional Neural Network and Support Vector Machine(CNNSVM)model is applied for sentiment classification of those keyword-generated *** method validation,the data randomly comprised of 5000 reviews from Amazon have been *** superior keyword extraction capability,the proposedmethod achieves impressive results on sentiment classification with a remarkable accuracy of up to 97.13%.Such performance demonstrates its advantages by using the text-to-image approach,providing a unique perspective for sentiment analysis in the e-commerce review data compared to the existing ***,the proposed method enhances the reliability and insights of customer feedback surveys,which would also establish a novel direction in similar cases,such as social media monitoring and market trend research.

关键词： Sentiment analysis keyword-generated image machine learning Word2Vec-TextRank CNN-SVM

Hierarchically porous Ni monolith@branch-structured NiCo2O4 for high energy density supercapacitors

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Progress in Natural Science:Materials International 2016年第3期26卷 276-282页

作者： Mengjie Xu rongjun Xu Ying Zhao Libao Chen Boyun Huang Weifeng Wei State Key Laboratory of Powder Metallurgy Central South University

A variety of NiCo2O4nanostrucutures ranging from nanowire to nanoplate and branched structures were successfully prepared via a simple hydrothermal process. The experimental results show that NiCo2O4with branched structures possesses the best overall electrochemical performance. The improvement of energy density was explored in terms of hierarchically three-dimensional（3D） metal substrates and a high specific area capacitance, and area energy density is obtained with hierarchically porous Ni monolith synthesized through a controlled combustion procedure.

关键词： Supercapacitors NiCo2O4 nanostructures Porous Ni monolith Energy density

絮凝-固化-真空预压联合处理废弃淤泥(浆)试验研究

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土木与环境工程学报（中英文） 2025年第1期47卷 27-35页

作者：韩超俞越中柏彬董超强章荣军范舟吴巍孙科国网江苏省电力有限公司建设分公司南京210000 华中科技大学土木与水利工程学院武汉430074

絮凝调理和化学固化改性处理能改善高含水率淤泥初始不良工程特性,将废弃淤泥(浆)资源化利用为路堤填料对淤泥强度有一定要求。已有研究证实了絮凝-固化-真空预压联合法(VPFSCM)可以有效处理高含水率淤泥浆(含水率>300%),且处理后的淤... 详细信息

絮凝调理和化学固化改性处理能改善高含水率淤泥初始不良工程特性,将废弃淤泥(浆)资源化利用为路堤填料对淤泥强度有一定要求。已有研究证实了絮凝-固化-真空预压联合法(VPFSCM)可以有效处理高含水率淤泥浆(含水率>300%),且处理后的淤泥强度满足路堤填料需求。通过室内模型箱试验探索VP-FSCM工艺处理废弃淤泥(含水率约为150%~300%)的可行性和高效性;优化VP-FSCM工艺在处理淤泥中的外加剂配方(类型和掺量等)。试验结果表明:VPFSCM处理废弃淤泥后土体28 d不排水抗剪强度为絮凝-固化法(FSCM)处理废弃淤泥后的2.76倍,证实了VP-FSCM处理废弃淤泥的高效、可行性。沉降脱水和力学等特性分析结果表明,VPFSCM工艺处理废弃淤泥的最佳外加剂种类为水泥(OPC)、高炉矿渣(GGBS)、生石灰(CaO)和聚丙烯酰胺(PAM),且最优掺量分别为5.0%、5.0%、1.5%、0.12%;在最佳外加剂类型和掺量条件下,真空压力越高,处理后的废弃淤泥不排水抗剪强度越高,养护后含水率越低。

关键词：废弃淤泥絮凝固化真空预压抗剪强度含水率

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Temperature measurement and analysis of postharvest agricultural products associated with thermal disinfestations

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International Journal of Agricultural and Biological Engineering 2013年第2期6卷 87-94页

作者： Yan rongjun Huang Zhi Li Rui Zhu Hankun Ling Bo Shaojin Wang College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingShaanxi 712100China Department of Biological Systems Engineering Washington State UniversityPullmanWA 99164-6120USA

Hot air and hot water treatments are practical,environmentally-friendly and non-chemical heating methods,which are widely used for postharvest insect control and quality preservation in agricultural *** apple and pear as representative fruits,this study mainly analyzed influences of their thermal properties,diameter,and medium speed on the heating rates of fruits through their real-time measured temperatures at surface and *** on the reported thermal death kinetic models of the target codling moth,the minimum heating time was estimated to achieve 100%insect *** results showed that the heating rates in fruits decreased gradually with the increasing depth from the surface to the *** increasing heating time,the heating rate became *** apple was heated faster than the *** water was more effective than hot air in treating *** hot air speed increased the heating rate but increasing water circulating speed had no clear effects on the heating *** on the measured temperature-time history of the fruit center,the minimum heating time could be effectively determined for codling moth control through the estimated total equivalent thermal lethal *** results could provide reliable validation data for the computer simulation and a scientific basis to improve the hot air and hot water treatments.

关键词： hot air hot water fruit postharvest treatment heating rates temperature measurement thermal disinfestation

A New Titanosauriform Sauropod from the Early Late Cretaceous of Dongyang,Zhejiang Province

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Acta Geologica Sinica(English Edition) 2008年第2期82卷 225-235页

作者： LU Junchang Yoichi AZUMA CHEN rongjun ZHENG Wenjie JIN Xingsheng Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Fukui Prefectural Dinosaur Museum 51-11 Terao Muroko Katsuyama 911-8601 Japan Dongyang Museum Dongyang Zhejiang 322100 China Zhejiang Museum of Natural History Hangzhou Zhejiang 310012 China

A new titanosauriform sauropod Dongyangosaurus sinensis gen. et sp. nov. from the early Late Cretaceous of Dongyang County, Zhejiang Province, is erected based on a partial postcranial skeleton. It is characterized by complex laminae on the lateral surface of the neural spines and postzygapophyses of dorsal vertebrae, a distinct fossa on the ventral surfaces of the prezygapophyses of dorsal vertebrae, distinct fossae are also present on the lateral surface of the postzygapophysis of anterior caudal vertebrae; pubis is shorter than ischium, the small obturator foramen of pubis elongated, and nearly closed. The lamina complexity of dorsal vertebrae in Dongyangosaurus indicates that a higher diversity of titanosauriformes occurred during the early Late Cretaceous in China.

关键词： Titanosauriformes Dongyangosaurus Fangyan Formation early Late Cretaceous,Zhejiang Province

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The Seismogenic Structure and Deformation Mechanism of the Lushan(MW 6.6) Earthquake, Sichuan, China

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Acta Geologica Sinica(English Edition) 2016年第2期90卷 503-510页

作者： ZHOU rongjun LI Yong SHAO Chongjian SU Jinrong YAN Zhaokun YAN Liang Sichuan Earthquake Administration Chengdu 610041 Sichuan China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Chengdu 610059 Sichuan China

On April 20 th, 2013, an earthquake of magnitude MW 6.6 occurred at Lushan of Sichuan on the southern segment of the Longmenshan fault zone, with no typical coseismic surface rupture. This work plotted an isoseismal map of the earthquake after repositioning over 400 post–earthquake macro–damage survey points from peak ground acceleration（PGA） data recorded by the Sichuan Digital Strong Earthquake Network. This map indicates that the Lushan earthquake has a damage intensity of IX on the Liedu scale, and that the meizoseismal area displays an oblate ellipsoid shape, with its longitudinal axis in the NE direction. No obvious directivity was detected. Furthermore, the repositioning results of 3323 early aftershocks, seismic reflection profiles and focal mechanism solutions suggests that the major seismogenic structure of the earthquake was the Dayi Fault, which partly defines the eastern Mengshan Mountain. This earthquake resulted from the thrusting of the Dayi Fault, and caused shortening of the southern segment of the Longmenshan in the NW–SE direction. Coseismal rupture was also produced in the deep of the Xinkaidian Fault. Based on the above seismogenic model and the presentation of coseismic surface deformation, it is speculated that there is a risk of more major earthquakes occurring in this region.

关键词： Lushan earthquake southern segment of Longmenshan seismogenic structure seismic risk

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