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Behcet’s disease manifesting as esophageal variceal bleeding: A case report

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World Journal of Clinical Cases 2021年第12期9卷 2854-2861页

作者： Wen-Xing Xie Hai-tao Jiang guo-qing Shi Li-Na Yang Hong Wang Department of Gastroenterology Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina

BACKGROUND Behcet’s disease(BD)is a chronic disease characterized by oral and vulvar ulcers as well as eye and skin damage and involves multiple *** presents as an alternating process of repeated attacks and *** venous rupture and bleeding caused by BD is rarely reported at home and *** paper reports a case of bleeding from oesophageal varices caused by BD,aiming to provide an additional dimension for considering the cause of bleeding from esophageal varices in the *** SUMMARY A 38-year-old female patient was admitted due to a gradual increase in shortness of breath and chest tightness after the activity,and was admitted to our hospital for *** admission,relevant examinations showed that the patient had multiple blood *** days after admission,she suddenly experienced massive *** esophagogastroduodenoscopy revealed bleeding from esophageal and gastric *** patient had no history of viral hepatitis or drinking habits,and no history of special genetic diseases or congenital vascular *** is no obvious abnormality in liver *** reviewing the medical history,it was found that the patient had recurred oral ulcers since childhood,ulcers were visible in the perineum during menstruation,and there was an intermittent red nodular rash and *** current skin acupuncture reaction is positive,combined with the evaluation of the external hospital and our hospital,the main diagnosis is *** received methylprednisolone,cyclophosphamide,immunomodulation,acid suppression,gastric protection,and anticoagulation and anti-infection treatments,and was discharged from the *** the 1-year follow-up period,the patient did not vomit blood *** This case highlights bleeding from esophageal varices caused by BD, aiming toprovide an additional dimension concerning the cause of bleeding fromesophageal varices in the future.

关键词： Behcet's disease Vasculitis Vascular embolism Esophageal variceal bleeding Case report

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油茶花苞采集机械手的设计与试验

农机化研究 2025年第1期47卷 46-53页

作者：赵青李立君吴泽超李骏郭鑫中南林业科技大学机电工程学院长沙410004

丘陵地区油茶林地众多,油茶花苞采集暂无机械化设备,故设计了一款六自由度的油茶花苞采集机械手。通过油茶花苞生物学特性分析,使用旋扭式末端执行器可以实现油茶花苞的高效采集,采净率为90%。通过机械手工作空间分析,确定了机械手的尺... 详细信息

丘陵地区油茶林地众多,油茶花苞采集暂无机械化设备,故设计了一款六自由度的油茶花苞采集机械手。通过油茶花苞生物学特性分析,使用旋扭式末端执行器可以实现油茶花苞的高效采集,采净率为90%。通过机械手工作空间分析,确定了机械手的尺寸,并将末端执行器搭载到机械手上进行了油茶林田间试验。试验结果表明:搭载了旋扭式末端执行器六自由度机械手,可以到达采摘区间的边界位置,末端在x、y、z方向的最大偏差分别为3.4、3.3、3.4 cm,为油茶花苞智能化采集提供了依据。

关键词：采集机械手生物学特性末端执行器油茶花苞

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Nonlinear dynamics of pork price in China

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Journal of Integrative Agriculture 2015年第6期14卷 1115-1121页

作者： ZHAO guo-qing WU Qiong School of Economics Renmin University of China

This paper primarily analyzes the evolution path of China＇s pork price by employing the threshold autoregression model（TAR）. Considering the unit root test with a threshold effect and heteroskedasticity of the TAR model, we show that the pork price series is a unit root process in each regime, and the heteroskedasticity in the TAR model greatly affects the results of linearity test. We find that the changing process of pork price has two regimes： mild regime and expansion regime. In particular, a change belongs to an expansion regime if it is larger than 0.5881; otherwise, it falls in the mild regime.

关键词： bootstrap regime volatility autoregressive otherwise belongs expenditure prices household EGARCH

Parallel interference cancellation for carrier frequency offset in OFDM assisted with recursive least squares algorithm

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 13-19页

作者： GUAN qing-yang ZHAO Hong-lin guo qing Communication Research Center Harbin Institute of Technology Harbin 150001 China

Parallel interference cancellation （PIC） interference due to the carrier frequency assisted with recursive least squares offset （CFO） in orthogonal frequency （RLS） algorithm is proposed to cancel the division multiplexing （OFDM） system. The proposed algorithm is composed of two stages, which are RLS scheme and PIC scheme. RLS scheme is selected to compensate the frequency offset in the time domain in the first stage, and the interference induced by residual frequency offset is canceled by the PIC scheme in the frequency domain in the second stage. The result of bit error rate （BER） shows that its performance is robust for cancellation as comparison criteria, even though the frequency offset is 0.45. The 16QAM constellation is also simulated to observe the improvements from the proposed suppression schemes.

关键词： OFDM CFO RLS PIC

Study on Atomic Fluorescence Spectrometry Excited by Synchrotron Radiation

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Chinese Journal of Chemical Physics 2008年第5期21卷 427-432页

作者： Jia-jia guo Wu-er Gana guo-bin Zhang qing-de Sua Department of Chemistry University of Science and Technology of China Hefei 230026 China National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230027 China

A novel analysis approach using atomic fluorescence excited by synchrotron radiation is presented. A system for synchrotron radiation-atomic fluorescence spectrometry is developed, and experimental conditions such as flow rate, analyte acidity, concentration of pre-reducing and hydrogenation system are optimized. The proposed method is successfully applied to get an excitation spectrum of arsenic. Seven of ten primary spectral lines, four of which have never been reported by means of atomic fluorescence spectrometry, agree well with the existing reports. The other three are proposed for the first time. Excitation potentials and possible transitions are investigated. Especially for the prominent line at 234.99 nm, the mechanism of generation is discussed and a model of energy transition processes is proposed.

关键词： Synchrotron radiation Atomic fluorescence Arsenic Energy transition

Parallel programming characteristics of a DSP-based parallel system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1669-1675页

作者： GAO Shu guo qing-ping School of Computer Science Wuhan University of Technology Wuhan 430063 China

This paper firstly introduces the structure and working principle of DSP-based parallel system, parallel accelerating board and SHARC DSP chip. Then it pays attention to investigating the system’s programming characteristics, especially the mode of communication, discussing how to design parallel algorithms and presenting a domain-decomposition-based complete multi-grid parallel algorithm with virtual boundary forecast (VBF) to solve a lot of large-scale and complicated heat problems. In the end, Mandelbrot Set and a non-linear heat transfer equation of ceramic/metal composite material are taken as examples to illustrate the implementation of the proposed algorithm. The results showed that the solutions are highly efficient and have linear speedup.

关键词： Parallel algorithm Multi-grid Domain decomposition Virtual boundary forecast (VBF) DSP-based parallel system

Some embedding theorems for W～(1,p)(Ω, H～n)

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Applied Mathematics(A Journal of Chinese Universities) 2010年第1期25卷 85-92页

作者： JIA Gao ZHANG guo-qing College of Science University of Shanghai for Science and Technology Shanghai 200090 China

For the maps on the Heisenberg group target, we prove a Poincare type inequality. Applying this Poincare type inequality, we obtain the corresponding versions of Sobolev and Rellich embedding theorems.

关键词： Heisenberg group HSlder continuity embedding theorem.

Contact dynamics of elasto-plastic thin beams simulated via absolute nodal coordinate formulation

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Acta Mechanica Sinica 2016年第3期32卷 525-534页

作者： qing-tao Wang Qiang Tian Hai-Yan Hu State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics MOE Key Laboratory of Dynamics and Control of Flight Vehicle School of Aerospace Engineering Beijing Institute of Technology

Under the frame of multibody dynamics, the contact dynamics of elasto-plastic spatial thin beams is numerically studied by using the spatial thin beam elements of absolute nodal coordinate formulation（ANCF）. The internal force of the elasto-plastic spatial thin beam element is derived under the assumption that the plastic strain of the beam element depends only on its longitudinal deformation.A new body-fixed local coordinate system is introduced into the spatial thin beam element of ANCF for efficient contact detection in the contact dynamics simulation. The linear isotropic hardening constitutive law is used to describe the elasto-plastic deformation of beam material, and the classical return mapping algorithm is adopted to evaluate the plastic strains. A multi-zone contact approach of thin beams previously proposed by the authors is also introduced to detect the multiple contact zones of beams accurately, and the penalty method is used to compute the normal contact force of thin beams in contact. Four numerical examples are given to demonstrate the applicability and effectiveness of the proposed elasto-plastic spatial thin beam element of ANCF for flexible multibody system dynamics.

关键词： Elasto-plastic deformation Linear isotropic hardening constitutive law Absolute nodal coordinate formulation(ANCF) Thin beam multi-zone contact dynamics

Multi-objective optimization of gas metal arc welding parameters and sequences for low-carbon steel (Q345D) T-joints

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Journal of Iron and Steel Research International 2017年第5期24卷 544-555页

作者： qing Shao tao Xu Tatsuo Yoshino Nan Song School of Mechanical Science and Engineering Jilin UniversityChangchun 130022JilinChina

Q345D high-quality low-carbon steel has been extensively employed in structures with stringent weld- ing quality requirements. A multi-objective optimization of welding stress and deformation was presented to design reasonable values of gas metal arc welding parameters and sequences of Q345D T-joints. The optimized factors included continuous variables （welding current （I）, welding voltage （U） ahd welding speed （V）） and discrete variables （welding sequence （S） and welding direc- tion （D））. The concepts of the pointer and stack in Visual Basic （VB） and the interpolation method were introduced to optimize the variables. The optimization objectives included the different combina- tions of the angular distortion and transverse welding stress along the transverse and longitudinal dis- tributions. Based on the design of experiments （DOE） and the polynomial regression （PR） model, the finite element （FE） results of the T-joint were used to establish the mathematical models. The Pareto front and the compromise solutions were obtained by using a multi-objective particle swarm optimization （MOPSO） algorithm. The optimal results were validated by the corresponding results of the FE method, and the error between the FE results and the two-objective results as well as that be-tween the FE results and the three-objective optimization results were less than 17.2% and 21.5%, respectively. The influence and setting regularity of different factors were discussed according to the compromise solutions.

关键词： T-joint Welding parameter Welding sequence Multi-objective optimization Pareto front Gas metal arc welding Q345D