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Comparison and Verification of Coherent Doppler Wind Lidar and Radiosonde Data in the Beijing Urban Area

Advances in Atmospheric Sciences 2024年第11期41卷 2203-2214页

作者： Zexu LUO Xiaoquan SONG Jiaping YIN Zhichao BU yubao CHEN yongtao yu Zhenlu ZHANG College of Marine Technology Faculty of Information Science and EngineeringOcean University of ChinaQingdao 266100China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQingdao 266237China Qingdao Leice Transient Technology Co.LTD Qingdao 266100China CMA Meteorological Observation Centre Beijing 100081China Beijing Municipal Meteorological Observation Center Beijing 102600China Qingdao Meteorological Comprehensive Support Center Qingdao 266003China

As a new type of wind field detection equipment, coherent Doppler wind lidar(CDWL) still needs more relevant observation experiments to compare and verify whether it can achieve the accuracy and precision of traditional observation equipment in urban areas. In this experiment, a self-developed CDWL provided four months of observations in the southern Beijing area. After the data acquisition time and height match, the wind profile data obtained based on a Doppler beam swinging(DBS) five-beam inversion algorithm were compared with radiosonde data released from the same location. The standard deviation(SD) of wind speed is 0.8 m s^(–1), and the coefficient of determination R~2 is 0.95. The SD of the wind direction is 17.7° with an R~2 of 0.96. Below the height of the roughness sublayer(about 400 m), the error in wind speed and wind direction is significantly greater than the error above the height of the boundary layer(about 1500 m). For the case of wind speeds less than 4 m s^(–1), the error of wind direction is more significant and is affected by the distribution of surrounding buildings. Averaging at different height levels using suitable time windows can effectively reduce the effects of turbulence and thus reduce the error caused by the different measurement methods of the two devices.

关键词： coherent Doppler wind lidar radiosonde wind measurement urban boundary layer

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围产期奶牛酮病的发病机制和预警标志物研究进展

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动物营养学报 2024年第6期36卷 3462-3473页

作者：程林马云马燕芬余永涛宁夏大学动物科技学院银川750021

奶牛酮病是围产期最常见的营养代谢病之一,患酮病的奶牛产奶量和繁殖性能下降,且易继发各种疾病,增加了治疗成本,给养殖业造成了巨大的经济损失,严重阻碍了奶牛业的健康发展。早期诊断和预测酮病的发生是防控的关键环节。目前,基于酮病... 详细信息

奶牛酮病是围产期最常见的营养代谢病之一,患酮病的奶牛产奶量和繁殖性能下降,且易继发各种疾病,增加了治疗成本,给养殖业造成了巨大的经济损失,严重阻碍了奶牛业的健康发展。早期诊断和预测酮病的发生是防控的关键环节。目前,基于酮病相关的血液、牛乳、尿液、瘤胃液、生理活动、生产管理数据等构建了奶牛酮病预测模型。本文围绕奶牛酮病的发病机制及早期诊断和预测研究进行了综述,以期为健全奶牛酮病风险预警体系提供理论依据。

关键词：奶牛酮病发病机制预警标志物

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宁夏部分地区哺乳期奶犊牛群中腹泻相关病原流行病学调查

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西北农业学报 2024年第9期33卷 1599-1613页

作者：崔省委赵清梅于鲲薛佳祺孙若菡李勇马云余永涛宁夏大学动物科技学院银川750021 北方民族大学生物科学与工程学院银川750021 宁夏大学生命科学学院银川750021

为了解宁夏地区哺乳期奶犊牛群中腹泻相关病原的流行情况,采用PCR和RT-PCR法对采自宁夏4个地区、18个规模化奶牛场的334份哺乳期犊牛粪便样品分别进行牛轮状病毒(Bovine rotavirus, BRV)、牛冠状病毒、牛病毒性腹泻病毒、牛诺如病毒(Bov... 详细信息

为了解宁夏地区哺乳期奶犊牛群中腹泻相关病原的流行情况,采用PCR和RT-PCR法对采自宁夏4个地区、18个规模化奶牛场的334份哺乳期犊牛粪便样品分别进行牛轮状病毒(Bovine rotavirus, BRV)、牛冠状病毒、牛病毒性腹泻病毒、牛诺如病毒(Bovine norovirus, BNoV)、牛纽布病毒、牛星状病毒、牛环曲病毒、牛嵴病毒(Bovine kobuvirus, BKoV)、牛肠道病毒、隐孢子虫、艾美耳球虫、贾第鞭毛虫、K99型大肠杆菌和沙门氏菌14种腹泻相关病原的检测,并对各种病原的流行特点和主要流行病原的遗传进化关系进行分析。结果显示,从宁夏地区哺乳犊牛粪便中共检出13种腹泻相关病原,其中隐孢子虫(38.02%)、BRV(19.76%)、BKoV(18.56%)和BNoV(13.77%)检出率较高,隐孢子虫、BRV和BKoV在腹泻犊牛粪便中的检出率显著高于健康犊牛(P<0.05)。单一病原感染类型占比显著高于两种或两种以上病原混合感染的类型(P<0.05)。在宁夏4个地区、3个季节采集的样品中,隐孢子虫、BRV、BKoV和BNoV检出率相对较高,在1~30日龄犊牛群中隐孢子虫、BRV和BKoV检出率较高,在31~60日龄犊牛中隐孢子虫和BNoV检出率较高,在60日龄以上的哺乳犊牛中BKoV、BEV和隐孢子虫检出率较高。遗传进化分析结果显示,哺乳犊牛感染的隐孢子虫主要为微小隐孢子虫,BRV主要为A型轮状病毒,BKoV主要为B型爱知病毒,BNoV主要为GⅢ.2型诺如病毒。以上结果表明,隐孢子虫、BRV、BKoV和BNoV是宁夏地区哺乳期奶犊牛群中主要流行的腹泻相关病原,并与犊牛腹泻的发生关系密切。单一病原感染是哺乳期奶犊牛腹泻相关病原感染的主要类型。犊牛感染的病原种类与季节和日龄关系密切。

关键词：哺乳期奶犊牛犊牛腹泻病原流行病学调查

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无人机锥形编队纯方位无源定位的研究

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移动信息 2024年第5期46卷 217-219页

作者：于永涛武建栋赵梦瑶河北工程大学河北邯郸056038

无人机编队飞行时应减少电磁波信号,采用纯方位无源定位来调整位置以保持队形,这是提升飞行效果的主流做法。文中首先基于同心圆几何模型,实现了锥形编队中无人机的位置判断。然后通过设计自适应调整方案,对位置有偏差的无人机进行调整... 详细信息

无人机编队飞行时应减少电磁波信号,采用纯方位无源定位来调整位置以保持队形,这是提升飞行效果的主流做法。文中首先基于同心圆几何模型,实现了锥形编队中无人机的位置判断。然后通过设计自适应调整方案,对位置有偏差的无人机进行调整。最后利用蒙特卡洛法进行了仿真模拟实验,验证了模型的有效性。除无人机外,其他采用纯方位无源定位的锥形编队也同样适用此模型和算法。

关键词：无人机锥形编队自适应调整模型回溯算法贪心策略

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A Polyp Detection Method Based on FBnet

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Computers, Materials & Continua 2020年第6期63卷 1263-1272页

作者： Jingjing Wan Taiyue Chen Bolun Chen yongtao yu Yiyun Sheng Xinggang Ma Department of Gastroenterology Affiliated Huaian Hospital of Xuzhou Medical UniversityThe Second People’s Hospital of HuaianHuaian223002China College of Computer Engineering Huaiyin Institute of TechnologyHuaian223003China University of Fribourg Fribourg1700Switzerland

The incidence of colorectal cancer(CRC)in China has increased in recent *** mortality rate of CRC has become one of the highest among all cancers;CRC increasingly affects the health and quality of people’s ***,due to the insufficiency of medical resources in China,the workload on medical doctors has further *** the past few decades,the adult CRC mortality and morbidity rate dropped sharply,mainly because of CRC screening and removal of adenomatous ***,due to the differences in polyp itself and the skills of endoscopists,the detection rate of polyps varies *** this paper,we adopt an anchor-free mechanism and introduce a better method to factorize the process of bounding box ***,we regress the shape of object by the variant of Faster ***,we re-define the target function of the location of *** experimental result shows that our method achieves a mAP of 55.8%,which outperforms other state-of-the-art methods by at least 11.9%.This will greatly help to reduce the missed diagnosis of clinicians during endoscopy and treatment,and provide effective help for early diagnosis,early treatment and prevention of CRC.

关键词： Colorectal cancer polyp detection anchor free two step decomposition

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Deep knowledge tracking algorithm based on forgetting law

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The Journal of China Universities of Posts and Telecommunications 2023年第1期30卷 17-27页

作者： Guo Xiangbo Wang Jian Huang Mengjie Wang Minghui Yang Jian yu yongtao School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou 450001China yunnan Key Laboratory of Smart City in Cyberspace Security Yuxi Normal UniversityYuxi 653100China

Knowledge tracking(KT)algorithm,which can model the cognitive level of learners,is a fundamental artificial intelligence approach to solve the personalized learning problem in the field of *** recently presented separated self-attentive neural knowledge tracing(SAINT)algorithm has got a great improvement on predictingthe accuracy of students’answers in comparison with the present other *** there is still potential to enhance its performance for it fails to effectively utilize temporal *** this paper,an optimization algorithm for SAINT based on Ebbinghaus’law of forgetting was proposed which took temporal features into *** proposed algorithm used forgetting law-based data binning to discretize the time information sequences,so as to obtain the temporal featuresin accordance with people’s forgetting *** the temporal features were used as input in the decoder of SAINT model to improve its *** experiments and comparison experiments were performed on the EdNet dataset in order to verify the effectiveness of the proposed *** in the experimental results,it achieved higher area under curve(AUC)values than the other present representative knowledge tracing *** demonstrates that temporal featuresare necessary for KT algorithms if it can be properly dealt with.

关键词： knowledge tracking neural network attention mechanism personalized learning Ebbinghaus' law of forgetting

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Research on Effect Airwake Acts on Glide Performance of Carrier-based Aircraft

Research on Effect Airwake Acts on Glide Performance of Carr...

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第26届中国控制与决策会议

作者： yu yongtao Zhang Zhi Shenyang Aerospace University Academy of Automation Harbin Engineering University Department of Automation

ISBN: (纸本)9781479937097

The kinematic model of carrier-based aircraft was established. The airwake model described in USA military standard was introduced and analyzed. A landing simulation system was build based on the kinematic model of aircraft and airwake model. Numerical simulation was carried out to research the effect that airwake acted on the flight performance of carrier-base aircraft. Simulation results show that the gliding track of aircraft affected by airwake is lower than reference gliding track, which reduces the landing safety. The random component and free-air turbulence component of airwake own the dominate part of effect, the steady component makes contribution too, the periodic component acts little effect on aircraft. Airwake affects flight performance of aircraft by putting effect on the aerodynamic force of aircraft but not aero dynamical moment.

关键词： Airwake Carrier-based aircraft Landing safety Landing simulation

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Design and mechanical properties analysis of a cellular Waterbomb origami structure

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 193-202页

作者： yongtao Bai Zhaoyu Wang yu Shi School of Civil Engineering Chongqing UniversityChongqing 400045China Research Center of Steel Structure Engineering Chongqing UniversityChongqing 400045China

Cellular structures are commonly used to design energy-absorbing structures,and origami structures are becominga prevalent method of cellular structure *** paper proposes a foldable cellular structure based on theWaterbomb origami *** geometrical configuration of this structure is ***-static compressiontests of the origami tube cell of this cellular structure are conducted,and load-displacement relationship curvesare *** simulations are carried out to analyze the effects of aspect ratio,folding angle,thicknessand number of layers of origami tubes on initial peak force and specific energy absorption(SEA).Calculationformulas for initial peak force and SEA are obtained by the multiple linear regression *** degree ofinfluence of each parameter on the mechanical properties of the single-layer tube cell is *** resultsshow that the cellular structure exhibits negative stiffness and periodic load-bearing capacity,as well as foldingangle has the most significant effect on the load-bearing and energy-absorbing *** adjusting the designparameters,the stiffness,load-bearing capacity and energy absorption capacity of this cellular structure can beadjusted,which shows the programmable mechanical properties of this cellular *** foldability andthe smooth periodic load-bearing capacity give the structure potential for application as an energy-absorbing structure.

关键词： Cellular structure Waterbomb origami Mechanical metamaterial Numerical simulation Energy absorption

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Air Quality Prediction Based on Kohonen Clustering and ReliefF Feature Selection

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Computers, Materials & Continua 2020年第8期64卷 1039-1049页

作者： Bolun Chen Guochang Zhu Min Ji yongtao yu Jianyang Zhao Wei Liu College of Computer Engineering Huaiyin Institute of TechnologyHuaian233003China Department of Physics University of FribourgFribourgCH-1700Switzerland College of Information Engineering Yangzhou UniversityYangzhou225009China

Air quality prediction is an important part of environmental *** accuracy of the air quality prediction also affects the planning of people’s outdoor *** to mine effective information from historical data of air pollution and reduce unimportant factors to predict the law of pollution change is of great significance for pollution prevention,pollution control and pollution early *** this paper,we take into account that there are different trends in air pollutants and that different climatic factors have different effects on air ***,the data of air pollutants in different cities are collected by a sliding window technology,and the data of different cities in the sliding window are clustered by Kohonen method to find the same tends in air *** this basis,combined with the weather data,we use the ReliefF method to extract the characteristics of climate factors that helpful for ***,different types of air pollutants and corresponding extracted the characteristics of climate factors are used to train different sub *** experimental results of different algorithms with different air pollutants show that this method not only improves the accuracy of air quality prediction,but also improves the operation efficiency.

关键词： Air quality prediction Kohonen clustering ReliefF feature selection

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Bionic design and performance test of maize grain cleaning screen through earthworm motion characteristics

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International Journal of Agricultural and Biological Engineering 2021年第3期14卷 12-21页

作者： Lijun Wang yongtao yu Shuai Zhang Xin Feng Lianglai Song College of Engineering Northeast Agricultural UniversityHarbin 150030China

The maize mixture feeding with a large mass cannot be migrated backward rapidly along the planar reciprocating vibrating screen,and it is easy to accumulate in the front of the screen,which leads to the decrease of screening *** on the reverse engineering technology,using the wavy geometry formed during the earthworm(Pheretima guillelmi)moving as a bionic prototype,a bionic screen was designed to make the maize mixture migrate backward rapidly in the front of the *** contour curve of earthworm’s head in an axial contracted state was extracted and fitted to obtain its *** on the difference of concave position of the lower surface’s wavy geometry during the earthworm moving,the motion of the bionic screen was divided into four postures,and the conversion between different postures of the bionic screen was realized by the cam drive *** kinematics simulation of the bionic screen was carried out through ADAMS,and the displacement and velocity of the bionic screen were *** the feeding mass of the maize mixture was set at 5 kg/s,6 kg/s and 7 kg/s,the test results showed that the time of the maize mixture migrated(TOMMM)in the front of the bionic screen was shortened by 0.18 s,0.71 s,and 1.36 s,respectively,compared with that of planar reciprocating vibrating *** total screening time(TST)of the bionic screen was shortened by 1.28 s,1.33 s,and 1.53 s,*** ability of the maize mixture to be migrated backward was *** study can provide a reference for the innovative design of the cleaning screen.

关键词： cleaning screen maize grain harvester material accumulation earthworm bionic design motion characteristics

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