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五轴NC加工干涉检查与避免算法研究

中国机械工程 2006年第17期17卷 1822-1825页

作者：严思杰周云飞陈学东赖喜德华中科技大学国家数控系统工程技术研究中心武汉430074 西华大学成都610039

利用刀具刃口回转面在两刀位点间运动形成的包络面方程与CAD模型面求交来实现五轴NC加工中干涉的判断与检验,依据检验结果对干涉进行处理,从而避免实际加工时干涉的发生。该方法考虑了刀具运动路径上全部刀位点的刀具与工件的位置关系,... 详细信息

利用刀具刃口回转面在两刀位点间运动形成的包络面方程与CAD模型面求交来实现五轴NC加工中干涉的判断与检验,依据检验结果对干涉进行处理,从而避免实际加工时干涉的发生。该方法考虑了刀具运动路径上全部刀位点的刀具与工件的位置关系,因而能够实现刀位轨迹全过程的干涉检验,避免了加工时对局部型面的破坏,有利于改善加工零件的表面质量。实际计算验证了该方法的可行性和实用性,具有一定的理论和实际意义。

关键词： CAD/CAM 五轴加工轨迹规划干涉包络面

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步进扫描光刻机硅片台连续扫描时间优化算法

机械工程学报 2008年第10期44卷 154-161页

作者：潘海鸿李小清严思杰陈琳周云飞华中科技大学机械科学与工程学院武汉430074 广西大学机械工程学院南宁530004

为减少步进扫描光刻机连续曝光扫描运动的扫描过渡时间(扫描时间和步进时间),将硅片台扫描方向曝光扫描运动分解为逻辑步进运动和逻辑扫描运动,提出扫描和步进运动时间重叠的轨迹规划算法(时间重叠算法)处理连续曝光扫描运动。在不破坏... 详细信息

为减少步进扫描光刻机连续曝光扫描运动的扫描过渡时间(扫描时间和步进时间),将硅片台扫描方向曝光扫描运动分解为逻辑步进运动和逻辑扫描运动,提出扫描和步进运动时间重叠的轨迹规划算法(时间重叠算法)处理连续曝光扫描运动。在不破坏运动约束条件下(恒速运动要求以及速度、加速度边界限制),根据时间重叠算法重新计算并推导不同扫描运动路径下连续扫描运动过程的步进和扫描运动转折点。经理论分析和硅片曝光场连续曝光实例计算表明:基于时间重叠算法的轨迹规划可获得时间优化的硅片台连续曝光扫描,比传统扫描方法减少曝光扫描运动过程中的无效率时间,提高步进扫描光刻机生产率,为步进扫描光刻机工程实践提供理论基础。

关键词：步进扫描光刻机硅片台连续曝光扫描时间重叠规划多项式运动轨迹

贴附射流变新风运行模式下冷辐射板结露特性研究

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流体机械 2021年第9期49卷 20-25,40页

作者：周璇玉丁云飞邓燕广州大学土木工程学院广州510006 广州大学广东省建筑节能与应用技术重点实验室广州510006

通过建立人体散湿模型,对冷辐射板结合诱导式新风口系统进行CFD瞬态模拟,分析室内人员变化,变新风量运行时新风贴附射流长度与贴附层内空气露点温度变化特性,探讨冷辐射空调中新风量动态调节规律,在满足卫生要求和不结露的同时,实现系... 详细信息

通过建立人体散湿模型,对冷辐射板结合诱导式新风口系统进行CFD瞬态模拟,分析室内人员变化,变新风量运行时新风贴附射流长度与贴附层内空气露点温度变化特性,探讨冷辐射空调中新风量动态调节规律,在满足卫生要求和不结露的同时,实现系统的运行节能。研究结果表明:在设计人数条件下,通过监测CO2浓度可使新风量在80%~100%范围内间歇调节;当室内人数减少时,可降低新风量,当新风量降低至室内除湿所需新风量时,应根据贴附层露点温度上升的速率适当调节新风量大小。

关键词：冷辐射板变新风量模式 CFD 贴附层露点温度

利用轨迹追踪法研究雅鲁藏布江大峡谷区域水汽输送减少的成因

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高原气象 2024年第1期43卷 114-126页

作者：张登旭阎虹如苗云飞张敏兰州大学大气科学学院半干旱气候变化教育部重点实验室甘肃兰州730000

雅鲁藏布江大峡谷区域作为高原的主要水汽输送入口,自1979年至今水汽通量辐合及降水量呈持续减少趋势,这对高原水储量具有重要影响。为了探究该区域水汽输送减少的原因,本文利用ERA5逐小时再分析资料驱动LAGRANTO模型,选取典型干旱年份... 详细信息

雅鲁藏布江大峡谷区域作为高原的主要水汽输送入口,自1979年至今水汽通量辐合及降水量呈持续减少趋势,这对高原水储量具有重要影响。为了探究该区域水汽输送减少的原因,本文利用ERA5逐小时再分析资料驱动LAGRANTO模型,选取典型干旱年份和湿润年份的夏季(6-8月),后向追踪该区域的水汽输送轨迹,对沿轨迹输送的水汽通量变化进行对比分析。研究发现,源自洋面的水汽主要来自高原南部的孟加拉湾,高原西南侧的阿拉伯海,赤道以南的印度洋以及南中国海四个区域,水汽输送主要受南亚和印度夏季风控制,并受索马里跨赤道急流影响。通过对比分析干、湿年份的水汽输送轨迹的特征,发现干湿年轨迹路径除南海源地外基本不变,轨迹上水汽通量随轨迹高度抬升而减少,且湿润年的损耗始终低于干旱年,其中孟加拉湾源地的轨迹得到洋面的水汽补充,在湿润年水汽通量有较强的增长。干湿年份的蒸发、降水、环流场形势的对比也佐证了这一发现。最终湿润年到达雅鲁藏布江峡谷边界的水汽通量大于干旱年,尤其是经由雅鲁藏布江峡谷区域南边界进入的水汽通量显著增大,这表明,除源地水汽贡献和大尺度季风环流影响外,水汽输送途中的降水损耗相关过程对雅鲁藏布江峡谷区域水汽收支具有决定性作用。

关键词：青藏高原水汽输送轨迹 LAGRANTO模式后向追踪

The relationship between cognitive impairment of patients with chronic benzene poisoning and brain: A case report

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The relationship between cognitive impairment of patients wi...

Changes of cognitive dysfunction and related brain regions in patients with chronic benzene poisoning:A case report

2019年浙江省医学会老年精神障碍学术大会

作者： Jiaojiao Hu Enyan Yu Zhengluan Liao Heng Su yunfei Tan Yaju Qiu Junpeng Zhu yan Chen Department of Psychiatry Bengbu Medical College Department of Psychiatry Zhejiang Cancer Hospital Department of Psychiatry Zhejiang Provincial People's Hospital of Hangzhou Medical College

Objective :To discuss the relationship between cognitive dysfunction and MRI performance in one patient with chronic occupational benzene *** :There are few studies on the damage to cognitive function of benzene toxic encephalopathy, and it is very important to identify whether the cognitive dysfunction is caused by benzene poisoning in both the early stage of the course of disease and its *** presentation:Here,we report a case of chronic benzene poisoning. The patient has been engaged in paint-related work for a long time whose main work is to paint the double sides of the swivel chair. She has been engaged in this work for more than five years. The main reasons for this visit are loss of appetite, fatigue for more than 2 months, memory loss for 1 month, which has impacted the ability of work and daily life seriously. The patient do not know acquaintances, do not know the way home, and weight loss about 5 kg for 2 *** :The cognitive function changes during the beginning of the disease 、treatment and 3 months after discharge of 1 patient with chronic benzene poisoning were analyzed based on cognitive function assessment and *** :Long-term exposure to benzene will cause damage to various systems of the human body, and affect functions, such as the hematopoietic system, the central system and so on. The cognitive impairment caused by chronic benzene poisoning is more hidden, and often does not take the direct cognitive function decline as the main manifestation, it is difficult to detect early. Regular screening of high-risk groups is necessary to significantly reduce the incidence of system damage caused by benzene poisoning.

关键词： Benzene poisoning Cognitive dysfunction MRI

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Changes of cognitive dysfunction and related brain regions i...

2019第四届之江精神医学交流会、浙江省医学会精神病学学术大会、浙江省医师协会精神科医师分会第十二届年会

作者： Jiaojiao Hu Enyan Yu Zhengluan Liao Heng Su yunfei Tan Yaju Qiu Junpeng Zhu yan Chen Department of Psychiatry Bengbu Medical CollegeChina Department of Psychiatry Zhejiang Cancer HospitalChina Department of Psychiatry Zhejiang Provincial People's Hospital of Hangzhou Medical CollegeChina

Objective:To discuss the changes of cognitive dysfunction and related brain regions in patients with chronic benzene ***:There is few study on the damage to cognitive function of benzene toxic encephalopathy,and it is very important to identify whether the cognitive dysfunction is caused by benzene poisoning in both the early stage of the course of disease and its *** presentation:Here,we report a case of chronic benzene *** patient has been engaged in paint-related work for more than five years whose primary work is to paint the double sides of the swivel *** main reasons for this visit are loss of appetite,fatigue for more than two months,and memory loss for 1 month,which has impacted the ability of work and daily life *** worries the patient's husband most is that she can't recognize acquaintances,can't find the way home,and have lost weight about 5 kg for two ***:We analysis the cognitive function changes during the beginning of the disease,treatment and three months after discharge of one patient with chronic benzene poisoning based on cognitive function assessment and ***:Long-term exposure to benzene will cause damage to central nervous *** cognitive impairment caused by chronic benzene poisoning is more hidden,and often doesn't take the direct cognitive function decline as the main clinical manifestation,which is difficult to detect *** screening of high-risk groups is necessary to significantly reduce the incidence of system damage caused by benzene poisoning.

关键词： Benzene poisoning Cognitive dysfunction Magnetic resonance imaging

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多孔高吸水性树脂孔结构的图像分析法

化工学报 2008年第10期59卷 2676-2679页

作者：陈煜颜荣华刘云飞谭惠民北京理工大学材料科学与工程学院北京100081

In this paper,an innovative method to study the structure of the porous superabsorbent polymers was *** using the Image J image processing software,the SEM pictures of the polymers were transformed into a binary sketch *** structure parameters of the pores could also be calculated with the aid of the *** to the principle of differential box counting,combined with the MATLAB programming,the fractal dimension of the porous superabsorbent polymers could be obtained through the binary sketch *** calculated fractal dimension could be used to express the regularity of the complicated structure of the porous superabsorbent *** the above process,the influence of the pre-swelling time for the porous superabsorbent polymers,prepared through the cryogenic induced phase separation method,on the structure of the modified polymer was discussed.

关键词：多孔高吸水性树脂图像分析分形

An Open Invitation to Join the International Brugada Electrocardiographic Indices Registry

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Cardiovascular Innovations and Applications 2020年第1期4卷 217-221页

作者： Gary Tse Sharen Lee Xuan Jiang Dong Chang yunfei Gu Zhengrong Huang Xintao Li Qunshan Wang Shaoying Zeng Guoliang Li Dan Hu Jiandong Zhou Qingpeng Zhang Gan-Xin yan Yunlong Xia Fang Zhou Liu Tong Liu Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease Department of CardiologyTianjin Institute of CardiologySecond Hospital of Tianjin Medical University300211 TianjinChina Xiamen Cardiovascular Hospital Xiamen UniversityXiamen361000 FujianChina Department of Cardiology The First Affi liated Hospital of Dalian Medical UniversityDalian116000 LiaoningChina Laboratory of Cardiovascular Physiology Li Ka Shing Institute of Health SciencesHong Kong Special Administrative RegionChina Department of Cardiology Guangdong Cardiovascular InstituteGuangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou510000 GuangdongChina Department of Cardiology Luoyang Central Hospital Affi liated to Zhengzhou UniversityLuoyang471009 HenanChina Department of Cardiology The First Affi liated Hospital of Xiamen UniversityXiamen361000 FujianChina Department of Cardiology The First People’s Hospital of ChangzhouChangzhou213000 JiangsuChina Department of Cardiology Xinhua HospitalSchool of MedicineShanghai Jiao Tong University200000 ShanghaiChina Guangdong General Hospital No.106 Zhongshan 2nd RoadYuexiu DistrictGuangzhou510080 GuangdongChina Arrhythmia Unit Department of Cardiovascular MedicineFirst Affi liated Hospital of Xi’an Jiaotong UniversityNo.277 Yanta West RoadXi’an710000 ShaanxiChina Department of Cardiology and Cardiovascular Research Institution Renmin Hospital of Wuhan UniversityWuhan430000 HubeiChina School of Data Science City University of Hong KongHong Kong Special Administrative RegionChina Lankenau Institute for Medical Research WynnewoodPA 19096USA

Background:The Brugada Electrocardiographic Indices Registry is a comprehensive data registry composed of patients with Brugada patterns on the electrocardiogram(ECG).The aim is to test the hypotheses that(i)ECG indices combining both depolarization and repolarization abnormalities can better predict spontaneous ventricular arrhythmias than existing ECG markers in Brugada syndrome and(ii)that serial ECG measurements will provide additional information for risk stratifi cation,especially in asymptomatic ***:Patients with both Brugada pattern ECGs and Brugada syndrome are eligible for inclusion in this *** characteristics and ECG variables refl ecting depolarization and repolarization will be *** primary outcome is spontaneous ventricular tachycardia/ventricular fi brillation or sudden cardiac *** outcomes are inducible ventricular tachycardia/ventricular fi brillation and ***:As of November 15,2019,39 investigators from 32 cities in 18 countries had joined this *** of December 15,2019,1383 cases had been ***:The Brugada Electrocardiographic Indices Registry will evaluate the disease life course,risk factors,and prognosis in a large series of Brugada *** will therefore provide insights for improving risk stratification.

关键词： Sudden cardiac death Brugada syndrome risk stratification electrocardiogram indices BEIR consortium

复杂机电系统制造过程项目化管理目标构建分析

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兵器装备工程学报 2020年第4期41卷 226-231页

作者：周云飞赛云秀闫莉西安工业大学机电工程学院西安710021 西安石油大学西安710065

针对复杂机电系统制造过程项目化管理的目标构建问题,创新构建了复杂机电系统项目的目标体系。通过将项目管理的三大目标机制引入到复杂机电系统制造过程中,明确定义进度、成本和质量三大目标,并指出三大目标是区别复杂机电系统项目与... 详细信息

针对复杂机电系统制造过程项目化管理的目标构建问题,创新构建了复杂机电系统项目的目标体系。通过将项目管理的三大目标机制引入到复杂机电系统制造过程中,明确定义进度、成本和质量三大目标,并指出三大目标是区别复杂机电系统项目与一般制造项目,特别是同类装备制造项目的重要标准,通过分析三大目标之间的权衡关系,构建了复杂机电系统项目统筹管理模型,并提出了统筹管理策略。研究结果可以为大型复杂装备制造企业实施项目化制造和管理提供参考。

关键词：复杂机电系统项目化管理三大目标统筹策略