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Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints

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Defence Technology（防务技术） 2024年第8期38卷 155-170页

作者： Ning Liu Wenjiang Zhao yao Wang Kai Shen zhong Su Wenhao Qi Yuedong xie Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science and Technology UniversityBeijing100192China Hua an Industry Group Co. Ltd.Qiqihar161006China Integrated Navigation and Intelligent Navigation Laboratory Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Beijing100081China

In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. In this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the missile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal estimation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 *** this method, the accurate acquisition of navigation parameters in the process of projectile launching is effectively realized.

关键词： Guided projectiles Tail spin reduction RPM constraints Combined navigation Extended Kalman filter(EKF)

Summer extreme precipitation patterns and synoptic-scale circulation precursors over the Tibetan Plateau

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Science China Earth Sciences 2024年第5期67卷 1625-1638页

作者： Zhiyuan DING yao HA zhong zhong College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing 210023China

In the context of global warming,the extreme summer precipitation over the Tibetan Plateau(TP)has changed *** this study,the summer(June–August)extreme precipitation on the TP was classified into three spatial types by applying the K-means clustering method to the Third Pole Region long time-series high-resolution(1/30°)precipitation dataset(TPHi Pr,1979–2020).The characteristics of the circulation anomalies and precursors corresponding to the extreme precipitation on the TP in summer during 1979–2020 were *** results showed that the summer extreme precipitation of the TP can be categorized into northwestern(NW),southeastern(SE),and southern Himalayan(HS)types based on extreme precipitation *** NW and SE types are mainly influenced by anomalous signals in the mid-to-high latitude regions upstream of them,whereas the HS type is controlled by the localized subtropical anomalous *** the 8th day before the onset of the NW type,an anomalous cyclone was observed in the western Atlantic Ocean(60°W,50°N),which triggered the west-to-east quasi-latitudinal propagation of Rossby *** the onset day of the NW type,the upper troposphere showed positive-negative-positive geopotential height anomalies along the latitudinal 40°N from the Caspian Sea,the western part of Xinjiang,to the northeastern *** entered from the Arabian Sea along the southeastern edge of the anomalous cyclone on the southwestern TP and converged in the northwestern *** to the NW type,the precursors of the SE type appeared at higher latitudes and were more *** the 8th day before the onset of the SE type,an anomalous cyclone occurred near Greenland(60°W,70°N)and excited Rossby waves propagating *** the onset day of the SE type,the upper troposphere showed negative-positive-negative geopotential height anomalies across Eurasia from the Ural Mountains and the Iranian Plateau to the northern TP in the northwest-southeast directi

关键词： Tibetan Plateau Summer extreme precipitation Atmospheric circulation anomaly Precursor Teleconnection wave train

Nosocomial Infection Surveillance in a Tuberculosis Specialized Hospital in China

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Biomedical and Environmental Sciences 2017年第9期30卷 691-694页

作者： xie zhong yao HUANG Guo Fang GAO Hui CHI Yu Qing WANG Yan Xia PANG Yu WANG Jing Ping Beijing Chest Hospital Capital Medical UniversityBeijing 101149China

Nosocomial infections（NIs） are a critical issue affecting the quality of healthcare. In this study, we performed a retrospective study to explore the incidence rates, mortality rates, and microbial spectrum of NIs in Beijing Chest Hospital, a tuberculosis（TB） specialized hospital in China. Our data demonstrate that the overall incidence rate of inpatients with NIs slightly decreased from 2012 to 2016, which may be associated with the implementation of hand hygiene measures, while the mortality rates associated with NI did not significantly change. In addition, the species distribution of NIs was quite different from that presented in previous reports, and Klebsiella pneumoniae was the most frequently isolated microorganism.

关键词： In Nosocomial Infection Surveillance in a Tuberculosis Specialized Hospital in China

Operational Characteristics of Loop Heat Pipe in Microgravity and Normal Gravity Environments

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Journal of Thermal Science 2024年第4期33卷 1394-1408页

作者： zhong Siyuan xie Rongjian LI Yunfei SUN Xiaojin Shanghai Institution of Technology and Physics Shanghai200083China University of Chinese Academy of Sciences Beijing100049China Shanghai Institute of Satellite Engineering Shanghai200240China

The loop heat pipe(LHP)is an advanced,efficient two-phase heat transfer unit,whose operational performance may be affected by microgravity conditions in contrast to ground-based *** performance of on-orbit temperature data and ground test of a copper-propylene LHP with a condenser temperature range of 243.15 K to 303.15 K were employed to compared and *** LHP has successfully started up for more than 193 times with a good heat transfer performance and a stable start-up stabilization on-orbit under a complex orbital heating environment for more than eight *** a small heat load(10.0W),the average start-up time is 110.0 s while the start-up temperature ranges from 5.71 K-12.78 *** start-up time at large temperature differences in the high temperature zone will be higher than the time required for start-up at smaller temperature differences in the low *** the condenser temperature is 250.0 K,the stable temperature difference on orbit is 3.83 K,which is generally consistent in heat transfer compared to 2.20 K in the ground *** this paper,we can conclude that the on-orbit flight data up to now can provide a reference to the design of subsequent LHP space applications.

关键词： Loop Heat Pipe(LHP) start up microgravity on-orbit experiment

Microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents during heat treatments

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Rare Metals 2024年第4期43卷 1786-1792页

作者： Yuan-Feng xie Xing-Cheng xie zhong-Wu Li Rui-Jun Cao zhong-Kun Lin Qing Li Chen-Guang Lin Powder Metallurgy and Special Materials Research Department General Research Institute for Nonferrous MetalsBeijing100088China

The effects of cryogenic treatment(CT)and tempering-cryogenic treatment(TCT)on the microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents were *** binder phase,WC mean grain sizes,W solubility in the binder,relative magnetic s aturation,densities,hardness,wear resistance and second phase precipitation of cemented carbides with different heat treatments were *** results show that there are significant changes of microstructure and properties in the samples with CT and TCT,especially due to the precipitation of metastable nanoparticles W_(x)Co_(y)C_(z) in the binder during the heat treatments of CT and *** the simultaneous combination of microstructure and nanoparticle-reinforced binder,a dramatically improved combination of hardness and wear resistance of the samples after TCT has been achieved.

关键词： Cryogenic treatment Tempering Coarsegrained cemented carbide Carbon content Nanoparticlereinforced binder

Waking Up Brain with Electrical Stimulation to Boost Memory in Sleep:A Neuroscience Exploration

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Neuroscience Bulletin 2024年第6期40卷 852-854页

作者： Zhe zhong Fuling Yan Chunming xie Department of Neurology School of MedicineAffiliated Zhongda HospitalSoutheast UniversityNanjing210009China Institute of Neuropsychiatry Affiliated Zhongda HospitalSoutheast UniversityNanjing210009China The Key Laboratory of Developmental Genes and Human Disease Southeast UniversityNanjing210009China

Imagine that,in the future,you could enhance your memory by applying a mild electric current to your brain during *** might sound like science fiction,but it is based on cutting-edge neuroscience *** is widely recognized as a crucial factor for long-term memory consolidation,but the exact mechanisms by which the brain coordinates neural activity across different regions during sleep to reorganize and integrate memories are unknown[1,2].

关键词： Sleep integrate applying

The Effect of Moisture in Different Altitude Layers on the Eastward Propagation of MJO

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Journal of Meteorological Research 2024年第3期38卷 437-452页

作者： Xiaoyu ZHU zhong zhong Yimin ZHU Yunying LI Yijia HU yao HA College of Meteorology and Oceanography National University of Defense TechnologyChangsha410000China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing210000China

In this study,driven by ERA5 reanalysis data,the Weather Research and Forecasting(WRF)version 4.0 was used to investigate the eastward propagation of the Madden-Julian oscillation(MJO)in the tropical atmosphere during December-February(DJF)of 2007/*** experiment with 11 cumulus parameterization schemes respectively shows that the Grell 3D scheme is one of several worse ones in describing MJO *** addition,still by use of the Grell 3D scheme,four nudging assimilation experiments for water vapor in all model vertical layers(Ndg_all),lower layers(Ndg_low),middle layers(Ndg_mid),and upper layers(Ndg_upp)were *** is found that when the water vapor in the model approaches to the observed value,the model performance for MJO activities is improved *** the four nudging simulations,Ndg_all certainly performs *** Ndg_mid is important for the MJO-filtered profiles related to moisture,Ndg_low and Ndg_upp exhibit superiority to Ndg_mid in simulating MJO eastward ***_low has advantages when MJO features are represented by zonal wind at 850 hPa and precipitation because the lower-level MJO-filtered moisture is conducive to the existence of lower-level condensational heating to the east of the MJO convective ***_upp performs better when describing the MJO eastward propagation features by outgoing longwave radiation(OLR)since it can capture the moisture and cloud top temperature of deep convection associated with MJO,as well as front Walker *** results suggest that the lower-level moisture is more important in regulating the MJO eastward propagation,and the observed maximum MJO-filtered moisture in the middle troposphere might be a phenomenon accompanying the MJO deep convection,but not a factor controlling its eastward propagation.

关键词： Madden-Julian oscillation(MJO) nudging technique Weather Research and Forecasting(WRF)model vertical moisture structure

Liver stiffness in hepatocellular carcinoma and chronic hepatitis patients:Hepatitis B virus infection and transaminases should be considered

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World Journal of Hepatology 2024年第7期16卷 1018-1028页

作者： Jia-yao Huang Jian-Yun Peng Hai-Yi Long Xian zhong Yu-Hua xie Lu yao Xiao-Yan xie Man-Xia Lin Department of Medical Ultrasonics The First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080Guangdong ProvinceChina

BACKGROUND Liver condition is a crucial prognostic factor for patients with hepatocellular carcinoma(HCC),but a convenient and comprehensive method to assess liver condition is *** stiffness(LS)measured by two-dimensional shear wave elastography may help in assessing liver fibrosis and liver *** hepatitis B(CHB)is an important risk factor for HCC progression,but LS was found to be less reliable in assessing liver fibrosis following hepatitis viral *** hypothesize that the status of hepatitis virus infection would affect the accuracy of LS in assessing the liver *** To test the feasibility and impact factors of using LS to assess liver condition in patients with HCC and *** A total of 284 patients were retrospectively recruited and classified into two groups on the basis of serum CHB virus hepatitis B virus(HBV)-DNA levels[HBV-DNA≥100.00 IU/mL as Pos group(n=200)and40 U/L),the correlations between LS and liver condition indices were not significant(P>0.05).CONCLUSION LS was significantly correlated with most liver condition indices in patients with CHB and ***,these correlations varied according to differences in HBV-DNA and transaminase concentrations.

关键词： Liver function Liver stiffness Elastography Chronic hepatitis B Hepatocellular carcinoma

Convergence analysis for complementary-label learning with kernel ridge regression

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 533-544页

作者： NIE Wei-lin WANG Cheng xie zhong-hua School of Mathematics and Statistics Huizhou UniversityHuizhou 516007China School of Computer Science and Engineering Huizhou UniversityHuizhou 516007China

Complementary-label learning(CLL)aims at finding a classifier via samples with complementary *** data is considered to contain less information than ordinary-label *** transition matrix between the true label and the complementary label,and some loss functions have been developed to handle this *** this paper,we show that CLL can be transformed into ordinary classification under some mild conditions,which indicates that the complementary labels can supply enough information in most *** an example,an extensive misclassification error analysis was performed for the Kernel Ridge Regression(KRR)method applied to multiple complementary-label learning(MCLL),which demonstrates its superior performance compared to existing approaches.

关键词： multiple complementary-label learning partial label learning error analysis reproducing kernel Hilbert spaces