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Chinese Science Bulletin 1998年第1期43卷 47-52页

作者： chen defeng, SUN Mei, LIU Yingmiao, SHI Guoli and chen Yawen Institute of Molecular Biology, Nankai University, Tianjin 300071, China Institute of Molecular Biology Nankai University Tianjin China

In 1991, we found that methylation outside the PvuⅡ recognition sequence could partially inhibit its cleavage activity. To clarify the molecular mechanism, three plasmids with different methylation states were constructed. Then, together with the original one, four plasmids were digested with different amounts of PvuⅡ. Results show that methylation on both sites results in 90% inhibition; moving the methylated site one base further away decreases the inhibitory effect to about 30%; with the adjacent dam methylation site eliminated, the inhibitory effect disappears. The data suggest that the inhibition of cleavage activity caused by outside methylation is not "all or none", and the degree of inhibition is dependent on the position and the number of methylated bases.

关键词： methylation outside the recognition sequence molecular mechanism PCR sitespecific mutation restriction endonuclease PvuⅡ.

A New Method for Anti-Noise FM Interference

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Wireless Sensor Network 2009年第4期1卷 293-299页

作者： Changyong JIANG Meiguo GAO defeng chen 不详

Noise Frequency Modulated (NFM) interference causes a disaster to almost all types of Radar systems. The echo signal and the interference are overlapped and because of strong energy of the NFM interference noth-ing could be detected except the interference in the Radar receiver system. Up to now no good method against NFM has been declared, conventional methods are based on the passive Radar to track the interfer-ence source which are not applicable under most conditions. Here a novel anti-noise FM method is proposed to suppress the NFM interference, the method multiply the mixed signal two times by different reference signals. The principle and some key factors of the new method are analyzed in detail and some rules for pa-rameters designing are given. What’s more, results show that the method can eradicate NFM effectively.

关键词： ECM ECCM NFM Interference Anti-NFM

A Preliminary Study of Computed Tomography for High-speed Rotation Object

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A Preliminary Study of Computed Tomography for High-speed Ro...

Assessment of surgical treatment impact the quality of life in 57 cases of patients with giant thyroid tumor in head and neck region

第十四届中国体视学与图像分析学术会议

作者： Wang Qian chen defeng Zhu Yining School of Mathematical Sciences .Capital Normal University

A new developed application of computed tomography(CT)is to inspect the deformation of the object in working stage.A typical case is the CT imaging of high-speed rotation object(HRO),such as the turbine blades of the operating *** to the relative rotation between HRO and the detector during a sampling time,the reconstructed result based on conventional reconstruction algorithms would suffer from blurred vision along the rotation *** this paper,we establish a mathematical model to describe the scanning data for HRO and present a principle for choosing the sampling time,which results in a deconvolution *** borrowing the idea of split Bregman,a deconvolution method with regard to Poisson noise is ***,from the deconvoluted data,the image of HRO is reconstructed by conventional reconstruction *** results for both simulation data and real data suggest that the proposed approach could reduce the motion blurring of CT images dramatically,even in the case of higher rotation speed or lower SNR.

关键词： Computed tomography High-speed rotation object Sampling design Deconvolution

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Assessment of surgical treatment impact the quality of life ...

基于雷达测距和测速的GEO目标实时关联算法

2014第六届全国甲状腺肿瘤学术大会

作者： Li Peng Qi Jinxing Luo Ruihua Wu Yao chen defeng Department of Head Neck and Thyroid The Affiliated Tumor Hospital of Zhengzhou University

Purpose:Quality of life（QOL） is an important treatment outcome for giant head and neck tumor. Our purpose of this study was to evaluate surgical treatment impact the quality of life in 57 cases of patients with giant tumor in head and neck region. Methods: The patients were divided into two groups: benign group（21 cases;36.84%） compare to malignant group（36 cases;63.16%）. QOL was assessed by the Performance status scale for head and neck cancer patients（PSS-HN） and the University of Washington Quality of Life（UW-QOL） questionnaires 12 months postoperatively before surgical treatment and at 1, 6, 12 months after operation. 57 of the 71 questionnaires（80.28%） were completed PSS-HN and UW-QOL at one or two time points during the treatment and follow-up periods. Results: QOL improved appearance in giant benign head and neck tumor, but deteriorated significantly in head and neck patient, especially in oral cavity and larynx cancer. The QOL in patients deteriorated by surgical treatment and it could be improved follow the time. Conclusions: PSS-HN, in con-junction with UW-QOL provides a valuable tool for the assessment of quality of life in giant tumor of head and neck before, during, and after treatment with surgery, which significantly influenced the patients’ QOL.

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北京航空航天大学学报 2023年第8期49卷 2167-2175页

作者：宋丽萍陈德峰田甜郭鑫北京理工大学信息与电子学院北京100081 北京轩宇信息技术有限公司北京100190

针对航迹密集情况下地球同步轨道(GEO)目标容易关联错误的问题,提出了一种基于雷达测距和测速二维判决的GEO目标实时关联算法。利用空间目标两行轨道根数(TLE)建立待关联初始库属目标集;根据空间目标轨道预报误差扩散规律设置粗关联门限... 详细信息

针对航迹密集情况下地球同步轨道(GEO)目标容易关联错误的问题,提出了一种基于雷达测距和测速二维判决的GEO目标实时关联算法。利用空间目标两行轨道根数(TLE)建立待关联初始库属目标集;根据空间目标轨道预报误差扩散规律设置粗关联门限,得到二次关联库属目标集;利用雷达测距和测速精度高的特点构建二次关联代价函数,根据归一化加权均方根误差最小原则得到关联结果。仿真结果表明:该算法在目标航迹密集的情况下取得了较好的关联效果,具有较高的关联正确率。

关键词：雷达二维判决密集航迹地球同步轨道实时关联

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高延性地聚合物与既有混凝土界面的黏结性能

建筑材料学报 2023年第8期26卷 914-921页

作者：李杉陈得锋卢亦焱李伟韬武汉大学土木建筑工程学院湖北武汉430072

对65个高延性地聚合物(HDGC)与既有混凝土的黏结试件进行了斜剪试验,研究了界面黏结角度、既有混凝土强度、HDGC延伸率和界面粗糙度对其界面黏结性能的影响,并基于Mohr-Coulomb屈服准则进行塑性极限分析,建立了破坏应力与界面黏结角度... 详细信息

对65个高延性地聚合物(HDGC)与既有混凝土的黏结试件进行了斜剪试验,研究了界面黏结角度、既有混凝土强度、HDGC延伸率和界面粗糙度对其界面黏结性能的影响,并基于Mohr-Coulomb屈服准则进行塑性极限分析,建立了破坏应力与界面黏结角度、内聚力和内摩擦角的计算式.结果表明:界面黏结角度对试件的失效模式起主要控制作用,界面黏结角度越大,试件的界面黏结强度越小;当既有混凝土强度提高时,试件的界面黏结强度略有降低;当HDGC延伸率为6.77%时,试件的界面黏结强度最大;随着界面粗糙度的增大,试件的界面黏结强度逐渐提高,但提高幅度呈降低趋势;建立的计算式计算结果与试验结果吻合较好.

关键词：地聚合物界面黏结性能失效模式塑性极限分析

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不闭合CT扫描数据几何伪影的校正方法

光学学报 2015年第6期35卷 103-111页

作者：于平陈德峰张慧滔张朋首都师范大学数学科学学院北京100048 首都师范大学检测成像北京高等学校工程研究中心北京100048

针对扇束计算机层析成像(CT)不闭合的扫描数据,提出一种基于非线性优化模型的CT几何伪影校正方法。该方法对标志物细丝与被测物体同时扫描,通过求解基于细丝断层投影数据的非线性优化模型,精确估计CT系统的所有几何参数,进而校正包括扫... 详细信息

针对扇束计算机层析成像(CT)不闭合的扫描数据,提出一种基于非线性优化模型的CT几何伪影校正方法。该方法对标志物细丝与被测物体同时扫描,通过求解基于细丝断层投影数据的非线性优化模型,精确估计CT系统的所有几何参数,进而校正包括扫描数据不闭合等几何参数误差引起的CT图像伪影。仿真和实测数据验证结果表明,利用本方法可有效消除不闭合扫描数据引起的CT图像几何伪影。

关键词：成像系统伪影校正非线性优化模型不闭合 CT扫描数据

坚持稳中求进工作总基调全面贯彻新发展理念大力推动新疆经济高质量发展

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新疆社科论坛 2019年第5期 63-65页

作者：陈德峰新疆维吾尔自治区人民政府研究室综合处

今年以来,全区稳定红利持续释放,高质量发展扎实推进,经济运行继续保持在合理区间,延续总体平稳、稳中有进的态势,主要宏观经济指标保持在合理区间,推动高质量发展的积极因素增多。但是,当前新疆经济正处于转变发展方式、优化经济结构... 详细信息

今年以来,全区稳定红利持续释放,高质量发展扎实推进,经济运行继续保持在合理区间,延续总体平稳、稳中有进的态势,主要宏观经济指标保持在合理区间,推动高质量发展的积极因素增多。但是,当前新疆经济正处于转变发展方式、优化经济结构、转换增长动力的攻坚期,在多重因素相互叠加的影响下,经济高质量发展仍面临严峻挑战,稳增长的任务仍然艰巨。要坚持稳中求进总基调,按照崇尚创新、注重协调、倡导绿色、厚植开放、推进共享的要求,坚决补齐新疆经济高质量发展的突出短板,在推动高质量发展的关键环节持续发力,让经济高质量发展的成果最大限度地惠及于民。

关键词：稳中求进新发展理念推动新疆经济高质量发展

基于PolyMax模态参数识别法的轴装式制动盘模态试验

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中国铁道科学 2020年第5期41卷 102-107页

作者：焦标强曹建行吕宝佳张化谦宋跃超陈德峰北京纵横机电科技有限公司北京100094 中国铁道科学研究院研究生部北京100081

针对结构复杂的轴装式制动盘模态参数无法采用有限元法快速准确识别的问题,基于PolyMax模态参数识别原理,搭建制动盘模态试验系统;采用锤击法进行轴装式制动盘的模态试验,运用PolyMax法对采集的频响函数数据进行模态参数识别,提取制动盘... 详细信息

针对结构复杂的轴装式制动盘模态参数无法采用有限元法快速准确识别的问题,基于PolyMax模态参数识别原理,搭建制动盘模态试验系统;采用锤击法进行轴装式制动盘的模态试验,运用PolyMax法对采集的频响函数数据进行模态参数识别,提取制动盘前10阶模态、阻尼和振型参数,分析制动盘的模态特性和传感器附加质量对制动盘模态频率的影响。结果表明:传感器附加质量对制动盘结构模态频率无影响;制动盘振动模态形式主要有周向模态、径向模态和混合模态3种类型,在频率1 627 Hz附近存在频率几乎一致的重根模态,模态复杂性比较低,近似为实模态振型,满足循环对称结构的典型模态振型特征;PolyMax模态参数识别法能快速准确地识别轴装式制动盘的模态参数,可为制动盘动力学特性分析和结构优化设计提供基础。

关键词：轴装式制动盘 PolyMax模态参数识别模态分析循环对称结构

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口腔修复工作中的医学伦理探讨

中国医学伦理学 2005年第2期18卷 64-65页

作者：陈德凤山东大学南区医院口腔科济南250061

口腔修复兼有功能恢复和美容的特点,作者从医学伦理的角度出发,探讨了口腔修复过程中应遵循的医德原则,以及避免医患纠纷的措施。

关键词：口腔修复医学伦理学医德原则