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Pre-Compensation for Continuous-Path Running Trajectory Error in High-Speed Machining of Parts with Varied Curvature Features

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Chinese Journal of Mechanical Engineering 2017年第1期30卷 37-45页

作者： jia Zhenyuan SONG dening MA jianwei GAO Yuanyuan Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China

Parts with varied curvature features play increasingly critical roles in engineering, and are often machined under high-speed continuous-path running mode to ensure the machining efficiency. However, the continuous-path running trajectory error is significant during high-feed-speed machining, which seriously restricts the machining precision for such parts with varied curvature features. In order to reduce the continuous-path running trajectory error without sacrificing the machining efficiency, a pre-compensation method for the trajectory error is proposed. Based on the formation mechanism of the continuous-path running trajectory error analyzed, this error is estimated in advance by approximating the desired toolpath with spline curves. Then, an iterative error pre-compensation method is presented. By machining with the regenerated toolpath after pre-compensation instead of the uncompensated toolpath, the continuous-path running trajectory error can be effectively decreased without the reduction of the feed speed. To demonstrate the feasibility of the proposed pre-compensation method, a heart curve toolpath that possesses varied curvature features is employed. Experimental results indicate that compared with the uncompensated processing trajectory, the maximum and average machining errors for the pre-compensated processing trajectory are reduced by 67.19% and 82.30%, respectively. An easy to implement solution for high efficiency and high precision machining of the parts with varied curvature features is provided.

关键词： trajectory error dynamic error pre-compensation continuous-path running high-feed-speed machining,parts with varied curvature features

Adaptive estimation and nonlinear variable gain compensation of the contouring error for precise parametric curve following

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Science China(Technological Sciences) 2017年第10期60卷 1494-1504页

作者： jia ZhenYuan SONG dening MA jianWei ZHAO XiaoXuan SU WeiWei Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education School of Mechanical Engineering Dalian University of Technology Dalian 116024 China

Contour following is one of the most important issues faced by many computer-numerical-control(CNC) machine tools to achieve high machining precision. This paper presents a new real-time error compensation method aiming at reducing the contouring error caused by facts such as servo lag and dynamics mismatch in parametric curved contour-following tasks. Due to the lack of high-precision contouring-error estimation method for free-form parametric curved toolpath, the error can hardly be compensated effectively. Therefore, an adaptive accurate contouring-error estimation algorithm is proposed first, where a tangential-error backstepping method based on Taylor's expansion is developed to rapidly find the closest point on the parametric curve to the actual motion position. On this foundation, the contouring error is compensated using a proposed nonlinear variable-gain compensation method, where the compensation gain is obtained according to not only the contouring-error magnitude but also its direction variation. The stability of the system after compensation is analyzed afterwards according to the Jury stability *** design of the compensator in accordance with the presented contouring-error compensation method as well as the stability analyzation result, the balance between the response speed and the contour control stability can be effectively made. Experimental tests demonstrate the feasibility of the presented methods in both contouring-error estimation and contour-accuracy *** of this research are significant for enhancing the contour-following performance of the CNC machine tools.

关键词： contouring error contour control adaptive error estimation variable gain compensation free-form parametric curves

Development of novel-nanobody-based lateral-flow immunochromatographic strip test for rapid detection of recombinant human interferon a2b

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Journal of Pharmaceutical Analysis 2022年第2期12卷 308-316页

作者： Xi Qin Maoqin Duan dening Pei jian Lin Lan Wang Peng Zhou Wenrong Yao Ying Guo Xiang Li Lei Tao Youxue Ding Lan Liu Yong Zhou Chuncui jia Chunming Rao Junzhi Wang National Institutes for Food and Drug Control Beijing100050China Synthetic and Functional Biomolecules Center Peking UniversityBeijing100871China WHO Collaboration Centre for Biologicals Standardization and Evaluation Beijing100050China

Recombinant human interferon a2b(rhIFNa2b)is widely used as an antiviral therapy agent for the treatment of hepatitis B and hepatitis *** current identification test for rhIFNa2b is *** this study,an anti-rhIFNa2b nanobody was discovered and used for the development of a rapid lateral flow strip for the identification of ***2b was used to immunize an alpaca,which established a phage nanobody *** five steps of enrichment,the nanobody I22,which specifically bound rhIFNa2b,was isolated and inserted into the prokaryotic expression vector *** subsequent purification,the physicochemical properties of the nanobody were determined.A semiquantitative detection and rapid identification assay of rhIFNa2b was developed using this novel *** develop a rapid test,the nanobody I22 was coupled with a colloidal gold to produce lateral-flow test *** developed rhIFNa2b detection assay had a limit of detection of 1 mg/*** isolation of I22 and successful construction of a lateral-flow immunochromatographic test strip demonstrated the feasibility of performing ligand-binding assays on a lateral-flow test strip using recombinant protein *** principle of this novel assay is generally applicable for the rapid testing of other commercial products,with a great potential for routine use in detecting counterfeit recombinant protein products.

关键词： Recombinant human interferon a2b Nanobody Phage display Screening Rapid test

ATM Optical Switching Technology

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The Journal of China Universities of Posts and Telecommunications 1999年第2期6卷 8-13页

作者： JI Yue-feng LI jia-ai CHEN Peng(Institute of Telecommunication Engineering, dening University of Posts and Telecommunications. Beijing, 100876, P. R. China) Institute of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P. R China

2.5 Gbit/s ATM optical switching experimental system has been achieved for the first time in *** poper describes the architecture of the ATM optical switching *** gives some key technologies forrealization,e.g. photonic switching matrix, header identification, etc. In addition, the performance, analysis andexperimental results are given.

关键词： optical switching Photonic switching ATM optiCal network

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基于蓝牙的数据采集上传系统

农业网络信息 2015年第10期 40-41页

作者：贾宇申张德宁河北农业大学机电学院河北保定071000

本文构建了一个基于蓝牙的数据采集上传系统。系统包括蓝牙设备的连接、数据传输与根据实验的数据包构建与发送,可以在实际生产中使用,适用于现场采集数据的整理和上传,具有一定的实用价值。

关键词：蓝牙数据包数据采集

基于作物水分胁迫指数的表层土壤含水率遥感估算

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灌溉排水学报 2023年第4期42卷 1-7页

作者：林人财陈鹤张德宁魏征蔡甲冰曾冉张丽莉贾玉玲中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038 德州市潘庄灌区运行维护中心山东德州253000 沧州市水利工程质量技术中心河北沧州061000

【目的】探究作物水分胁迫指数(CWSI)与表层土壤含水率的空间分布特征,并分析不同下垫面(葵花、夏玉米、春小麦和甜椒)表层土壤含水率的遥感估算精度。【方法】利用MOD16A2遥感数据和气象数据,结合Penman-Monteith(P-M)模型,基于CWSI反... 详细信息

【目的】探究作物水分胁迫指数(CWSI)与表层土壤含水率的空间分布特征,并分析不同下垫面(葵花、夏玉米、春小麦和甜椒)表层土壤含水率的遥感估算精度。【方法】利用MOD16A2遥感数据和气象数据,结合Penman-Monteith(P-M)模型,基于CWSI反演河套灌区解放闸灌域表层土壤含水率,并对不同下垫面的表层土壤含水率进行验证。【结果】CWSI的空间分布与表层土壤含水率相反,CWSI大的区域,表层土壤含水率小;春小麦下垫面遥感估算的表层土壤含水率效果较好,决定系数(R^(2))为0.748,其次为葵花,R^(2)为0.357;灌溉次数较多的夏玉米和甜椒的表层土壤含水率估算精度较差,可见基于CWSI的表层土壤含水率遥感估算方法对土壤干旱较为敏感。【结论】基于CWSI的表层土壤含水率遥感估算方法更适用于灌水较少且耐旱作物下垫面的表层土壤含水率估算。

关键词：土壤含水率 CWSI MOD16A2 解放闸灌域

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毛细管区带电泳法测定重组人干扰素α-1b滴眼液中间甲酚含量

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中国药师 2018年第9期21卷 1575-1576,1585页

作者：李响于雷裴德宁贾春翠周勇饶春明中国食品药品检定研究院重组药物室北京100050

目的:运用毛细管区带电泳法(CZE)检测重组人干扰素α^(-1)b(rh IFNα^(-1)b)滴眼液中间甲酚含量。方法:优化的CZE方法参数为采用无涂层的熔融石英毛细管(60 cm×50μm),电泳缓冲液为50 mmol·L^(-1)磷酸盐缓冲液(p H 8.0),压力进样(1.0 ... 详细信息

目的:运用毛细管区带电泳法(CZE)检测重组人干扰素α^(-1)b(rh IFNα^(-1)b)滴眼液中间甲酚含量。方法:优化的CZE方法参数为采用无涂层的熔融石英毛细管(60 cm×50μm),电泳缓冲液为50 mmol·L^(-1)磷酸盐缓冲液(p H 8.0),压力进样(1.0 psi),分离电压25 k V,检测波长195 nm,毛细管温度25℃。结果:间甲酚在0.05~0.8 mg·ml^(-1)浓度范围内与峰面积呈良好线性关系(r=0.997 3),最低检出限0.002 mg·ml^(-1)。3批rh IFNα1b滴眼液中间甲酚的相对含量分别为1.94,1.89和1.97 mg·ml^(-1),平均回收率分别为94.3%(RSD=1.57%,n=9)。结果与HPLC方法结果基本一致。结论:新建毛细管区带电泳法简便,分析速度快,试剂消耗量小,结果准确,可以用于重组人干扰素α1b滴眼液中间甲酚含量的检测。

关键词：重组人干扰素α-1b滴眼液毛细管区带电泳间甲酚