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变矩器壳体智能洁净制造生产线设计

制造技术与机床 2024年第8期 16-25页

作者：张彦彬孙令伊徐帅强赵永军许文昊李长河青岛理工大学机械与汽车工程学院山东青岛266520 迈赫机器人自动化股份有限公司智能制造技术研究院山东潍坊262200

变矩器壳体作为汽车发动机中的重要零部件,具有多样化、复杂化的外形特征和加工工艺。然而,传统的变矩器壳体生产线存在高耗低效、依赖工人操作生产效率低等问题,迫切需要向着绿色化、智能化的方向转型。基于此,开展了变矩器壳体智能洁... 详细信息

变矩器壳体作为汽车发动机中的重要零部件,具有多样化、复杂化的外形特征和加工工艺。然而,传统的变矩器壳体生产线存在高耗低效、依赖工人操作生产效率低等问题,迫切需要向着绿色化、智能化的方向转型。基于此,开展了变矩器壳体智能洁净制造生产线设计工作。结合现有生产线存在的问题,对变矩器壳体智能洁净制造生产线做出优化,完成了变矩器壳体智能洁净制造生产线硬件系统设计、分体式变矩器壳体加工工艺设计以及变矩器壳体生产线工艺装备系统设计。以平均生产节拍为指标,智能洁净制造生产线生产效率提升55.1%。

关键词：生产线智能化洁净制造加工工艺变矩器壳体

保定市某医院介入放射学工作人员受照剂量及健康状况分析

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医学动物防制 2024年第2期40卷 152-155页

作者：许振华李菲赵永军魏鹏飞马倩狄云雯罗英男保定市疾病预防控制中心河北保定071000 河北省疾病预防控制中心

目的了解保定市某医院介入放射学工作人员个人受照剂量水平及健康状况,从而评价放射管理措施的效果,为加强介入放射学工作人员的管理提供依据。方法收集2019-2020年保定市某医院从事放射工作的2 072人次个人受照剂量监测资料和109人... 详细信息

目的了解保定市某医院介入放射学工作人员个人受照剂量水平及健康状况,从而评价放射管理措施的效果,为加强介入放射学工作人员的管理提供依据。方法收集2019-2020年保定市某医院从事放射工作的2 072人次个人受照剂量监测资料和109人次介入放射学工作人员体检资料,采用非参数Kruskal-Wallis H检验、logistic回归分析及Pearson χ^(2)检验对结果进行描述和分析。结果各职业照射种类,人均年有效剂量水平差异有统计学意义(H=45.033,P0.05);不同剂量区间介入放射学工作人员的体检结果差异均无统计学意义(χ^(2)=4.246、1.037、3.949,均P>0.05)。结论应加强介入放射学工作人员的辐射防护措施,减少其辐射暴露时间。

关键词：电离辐射介入放射学放射工作人员个人剂量健康体检分析

Coherent Integration Algorithm for Frequency-Agile and PRF-Jittering Signals in Passive Localization

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Chinese Journal of Electronics 2021年第4期30卷 781-792页

作者： JIANG Hongzhi zhao Chuang zhao yongjun PLA Strategic Support Force Information Engineering University

Increasing pulses Coherent processing interval(CPI) can effectively improve the location parameters estimation performance in passive ***, for a moving emitter transmitting pulses with Frequency agile and Pulse repetition frequency jittering(FA-PRFJ) in a CPI, there will exist random phase, uneven sampling and Range migration(RM),which deteriorates the estimation performance of location parameters. Aiming at long-time coherent localization parameters estimation for the above emitter, this paper proposes a joint Range difference(RD) and Range rate difference(RRD) estimation algorithm. Firstly, the signal model of a moving emitter transmitting FA-PRFJ signal is constructed, and the influence of the FA and PRFJ on coherent integration is analyzed. Secondly, the random phase induced by FA is eliminated by frequency symmetric autocorrelation function operation. Then, RD and RRD can be coherently estimated after RM correction via the modified scaled non-uniform fast Fourier transform. This method can be efficiently implemented by Fast Fourier transform(FFT), inverse FFT and FFT-based chirp-z transform without any searching operation. Simulation results demonstrate that the proposed method has a better antinoise capability with a much lower computational complexity compared with several representative methods.

关键词： Passive localization Coherent integration Moving emitter Frequency agile Pulse repetition frequency jittering Range difference Range rate difference

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前起落架平行度工艺研究

机械工程师 2024年第4期 154-156页

作者：王奉龙赵勇军娄雷亭谯正中航飞机股份有限公司、长沙起落架分公司陕西汉中723000

当飞机起飞后起落架收起,前起落架中立位置尤为关键,前起落架平行度通过凸轮配加工保证,不仅对现场操作人员技能水平要求较高,还需对产品反复拆装,延长产品生产周期,并且因为配加工而无法实现产品通用,造成产品返修难度大。文中通过精... 详细信息

当飞机起飞后起落架收起,前起落架中立位置尤为关键,前起落架平行度通过凸轮配加工保证,不仅对现场操作人员技能水平要求较高,还需对产品反复拆装,延长产品生产周期,并且因为配加工而无法实现产品通用,造成产品返修难度大。文中通过精准控制零件加工精度,协调关键零件形位尺寸,保证前起落架平行度要求,取消传统配加工方法,提升零件互换性,消除零件专配关系,实现产品的互换性、通用性。

关键词：中立位置平行度前起落架

Moving target localization for multistatic passive radar using delay, Doppler and Doppler rate measurements

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Journal of Systems Engineering and Electronics 2020年第5期31卷 939-949页

作者： zhao Yongsheng HU Dexiu zhao yongjun LIU Zhixin Data and Target Engineering Institute PLA Strategic Support Force Information Engineering UniversityZhengzhou 450001China

Time delay and Doppler shift between the echo signal and the reference signal are two most commonly used measurements in target localization for the passive radar. Doppler rate, which can be obtained from the extended cross ambiguity function, offers an opportunity to further enhance the localization accuracy. This paper considers using the measurement Doppler rate in addition to measurements of time delay and Doppler shift to locate a moving target. A closed-form solution is developed to accurately and efficiently estimate the target position and *** proposed solution establishes a pseudolinear set of equations by introducing some additional variables, imposes weighted least squares formulation to yield a rough estimate, and utilizes the function relation among the target location parameters and additional variables to improve the estimation accuracy. Theoretical covariance and Cramer-Rao lower bound(CRLB) are derived and compared, analytically indicating that the proposed solution attains the CRLB. Numerical simulations corroborate this analysis and demonstrate that the proposed solution outperforms existing methods.

关键词： target localization multistatic passive radar time delay Doppler shift Doppler rate

Moving target localization in distributed MIMO radar with transmitter and receiver location uncertainties

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Chinese Journal of Aeronautics 2019年第7期32卷 1705-1715页

作者： Yongsheng zhao Dexiu HU yongjun zhao Zhixin LIU National Digital Switching System Engineering and Technological Research Center (NDSC)

In this paper, the problem of moving target localization from Bistatic Range(BR) and Bistatic Range Rate(BRR) measurements in a Multiple-Input Multiple-Output(MIMO) radar system having widely separated antennas is investigated. We consider a practically motivated scenario,where the accurate knowledge of transmitter and receiver locations is not known and only the nominal values are available for processing. With the transmitter and receiver location uncertainties,which are usually neglected in MIMO radar systems by prior studies, taken into account in the measurement model, we develop a novel algebraic solution to reduce the estimation error for moving target localization. The proposed algorithm is based on the pseudolinear set of equations and two-step weighted least squares estimation. The Cramer-Rao Lower Bound(CRLB) is derived in the presence of transmitter and receiver location uncertainties. Theoretical accuracy analysis demonstrates that the proposed solution attains the CRLB, and numerical examples show that the proposed solution achieves significant performance improvement over the existing algorithms.

关键词： Bistatic range Bistatic range rate Location uncertainty MIMO radar Target localization Two-step weighted least squares

Accurate single-observer passive coherent location estimation based on TDOA and DOA

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Chinese Journal of Aeronautics 2014年第4期27卷 913-923页

作者： Li Jing zhao yongjun Li Donghai Zhengzhou Information Science and Technology Institute Huanghe Science and Technology College

This paper investigates the problem of target position estimation with a single-observer passive coherent location（PCL） system. An approach that combines angle with time difference of arrival（ATDOA） is used to estimate the location of a target. Compared with the TDOA-only method which needs two steps, the proposed method estimates the target position more directly. The constrained total least squares（CTLS） technique is applied in this approach. It achieves the Cramer–Rao lower bound（CRLB） when the parameter measurements are subject to small Gaussian-distributed errors. Performance analysis and the CRLB of this approach are also studied. Theory verifies that the ATDOA method gets a lower CRLB than the TDOA-only method with the same TDOA measuring error. It can also be seen that the position of the target affects estimating *** the same time, the locations of transmitters affect the precision and its gradient *** with the TDOA, the ATDOA method can obtain more precise target position ***, the proposed method accomplishes target position estimation with a single transmitter,while the TDOA-only method needs at least four transmitters to get the target position. Furthermore,the transmitters＇ position errors also affect precision of estimation regularly.

关键词： Constrained total leastsquares Cramer-Rao bounds Direction of arrival Passive coherent location Time difference of arrival

Polyphyllin Ⅰ enhances tumor necrosis factor-related apoptosis-inducing ligand-induced inhibition of human osteosarcoma cell growth via downregulating the Wnt/β-catenin pathway

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Journal of Traditional Chinese Medicine 2024年第2期44卷 251-259页

作者： CHANG Junli zhao Fulai SUN Xingyuan MA Xiaoping zhao Peng ZHOU Chujie SHI Binhao GU Wenchao WANG yongjun YANG Yanping Spine Disease Institute Longhua Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200032China Department of Diagnostic and Interventional Radiology University of TsukubaIbaraki 315-0114Japan

OBJECTIVE:To investigate the synergistic effects of polyphyllin Ⅰ(PPⅠ)combined with tumor necrosis factorrelated apoptosis-inducing ligand(TRAIL)on the growth of osteosarcoma cells through downregulating the Wnt/β-catenin signaling ***:Cell viability,apoptosis and cell cycle distribution were examined using cell counting kit-8 and flow cytometry *** morphology of cancer cells was observed with inverted phase contrast *** migration and invasion abilities were examined by xCELLigence real time cell analysis DP system and transwell *** expressions of poly(adenosine diphosphate-ribose)polymerase,C-Myc,Cyclin B1,cyclin-dependent kinases 1,N-cadherin,Vimentin,Active-β-catenin,β-catenin,p-glycogen synthase kinase 3β(GSK-3β)and GSK-3βwere determined by Western blotting ***:PPⅠ sensitized TRAIL-induced decrease of viability,migration and invasion,as well as increase of apoptosis and cell cycle arrest of MG-63 and U-2 OS osteosarcoma *** synergistic effect of PPⅠwith TRAIL in inhibiting the growth of osteosarcoma cells was at least partially realized through the inactivation of Wnt/β-catenin signaling ***:The combination of PPⅠ and TRAIL is potentially a novel treatment strategy of osteosarcoma.

关键词： osteosarcoma tumor necrosis factor-related apoptosis-inducing ligand Wnt signaling pathway beta-catenin polyphyllinⅠ

In patients who had a stroke or TIA, enlarged perivascular spaces in basal ganglia may cause future haemorrhagic strokes

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Stroke & Vascular Neurology 2024年第1期9卷 8-17,I0001-I0033页

作者： Yu Tian Mengxing Wang Yuesong Pan Xia Meng Xingquan zhao Liping Liu yongjun Wang Yilong Wang Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Chinese Institute for Brain Research BeijingChina National Center for Neurological Diseases BeijingChina Advanced Innovation Center for Human Brain Protection Capital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina

Introduction It remains unclear whether enlarged perivascular spaces(EPVS)predict poor clinical outcomes in patients with acute ischaemic stroke(AIS)or transient ischaemic attack(TIA).Method Data were obtained from the Third China National Stroke Registry *** estimated EPVS in basal ganglia(BG)and centrum semiovale(CSO)using a semiquantified scale(Grade from 0 to 4).Using Cox and logistic regression analyses,the associations of EPVS with 3-month and 1-year adverse outcomes(including recurrent stroke,ischaemic stroke,haemorrhagic stroke,combined vascular event,disability and mortality)were *** analyses of any association of cerebral small vessel disease at baseline and development of a small arterial occlusion(SAO)were *** Among 12603 patients with AIS/TIA,median age was 61.7±11.6 years,and 68.2%were *** adjusting for all potential confounders,frequent-to-severe BG-EPVS was associated with a decreased risk of recurrent ischaemic stroke(HR 0.71,95%CI 0.55 to 0.92,p=0.01)but an increased risk of haemorrhagic stroke(HR 1.99,95%CI 1.11 to 3.58,p=0.02)at 1 year after AIS/TIA,compared with none-to-mild *** with frequent-to-severe CSO-EPVS had a decreased risk of disability(OR 0.76,95%CI 0.62 to 0.92,p=0.004)and all-cause death(HR 0.55,95%CI 0.31 to 0.98,p=0.04)within 3-month but not 1-year follow-ups,compared with those with none-to-mild *** analyses showed that both BG-EPVS(HR 0.43,95%CI 0.21 to 0.87,p=0.02)and CSO-EPVS(HR 0.58,95%CI 0.35 to 0.95,p=0.03)were associated with a decreased risk of subsequent ischaemic stroke in patients with SAO during 1-year *** BG-EPVS increased the risk of haemorrhagic stroke in patients already with AIS/TIA within 1 ***,caution is recommended when selecting antithrombotic agents for secondary stroke prevention in patients with AIS/TIA and more severe BG-EPVS.

关键词： patients haemorrhagic prevention