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Fingered Intrusion of Shallow Saucer-shaped Igneous Sills: Insights from the Jiaojiang Sag, East China Sea 被引量:8
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作者 GUO Rui ZHANG Gongcheng +4 位作者 ZHANG Jinwei ZHAO Xingbin LIU Junbang YUAN Dawei SONG Shuang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第5期1306-1318,共13页
An extensive suite of igneous sills was intruded into the Tertiary sedimentary section of the Jiaojiang sag, East China Sea. This suite has been well imaged offshore through 2D and 3D seismic surveys, showing a close ... An extensive suite of igneous sills was intruded into the Tertiary sedimentary section of the Jiaojiang sag, East China Sea. This suite has been well imaged offshore through 2D and 3D seismic surveys, showing a close relationship with CO2 content in nearby gas discoveries. A new observational model, which incorporates simple upward propagation, simple horizontal propagation, and transgressive propagation, was proposed to interpret these sill intrusions. In this model, the source magma of the saucer-shaped sills was injected from their lowest points near the center. The transgressive propagation can be interpreted as a combination of the vertical and horizontal propagation. Most shallow sub-volcanic intrusions in the Jiaojiang sag exhibit fingered characteristics, both vertically and horizontally. The vertical fingered propagation produced saucer-shaped sills arranged in the flower style. Along the brims of lower sills could usually be found the upper sills, which are interpreted to have formed simultaneously with or later than the lower feeder sills. In the second type, the chilled paths of the older sills were reutilized by subsequent intrusions. The horizontal fingered propagation formed sheet intrusions that exhibit groove, lobate, tubular, and crevasse splay- like geometry in plan view. In 3D view, the sheet intrusions have still preserved the lower center and higher rim that similar with the sub-rounded saucer-shaped sills. Although fracture propagation may be important, flow inflation was the key mechanism of magma intrusion. Further consideration of the mechanisms underlying sill formation may help explain the fingered characteristics of sill propagation. 展开更多
关键词 saucer-shaped sill fingered intrusion feeder relationship lobate sill flow inflation Jiaojiang sag
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Using Wing Tip Devices to Improve Performance of Saucer-Shaped Aircraft 被引量:4
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作者 于军力 王林林 高歌 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第4期309-314,共6页
Saucer-shaped aircraft adopts a novel aerodynamic configuration of blending fuselage with wing. In contrast to the ordinary aircraft configurations, this kind of configuration can totally eliminate the drag resulted f... Saucer-shaped aircraft adopts a novel aerodynamic configuration of blending fuselage with wing. In contrast to the ordinary aircraft configurations, this kind of configuration can totally eliminate the drag resulted from fuselage, bringing many advantages such as simple structure, compact scale, high load capability. But its small aspeet ratio makes the induced drag higher. Through wind tunnel experiments, it is discovered that a type of sweepback fin-shaped winglet can efficiently reduce the induced drag of this kind of aircraft. When this winglet is mounted to a model in wind tunnel experiment, the maximal ratio of lift to drag of the model can be increased by 75% as compared with the model without winglet at the speed of 30 m/s, and reached 15 at the speed of 50 m/s. In order to investigate the performance of this aircraft with winglet at low speed, test flights were processed. The results of test flights not only verify the conclusions of experiments in wind tunnel but also indicate that the load capability of the aircraft with winglet is increased and its lateral stability is even better than that of the aircraft without winglet. 展开更多
关键词 saucer-shaped aircraft sweepback fro-shaped winglet reduction of induced drag
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Dynamics modeling and simulation of a saucer-shaped stratospheric aerostat with an under-slung nacelle
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作者 ZHAO Ming XIAO Chang +1 位作者 ZHOU Ping-fang DUAN Deng-ping 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1288-1298,共11页
A new concept stratospheric aerostat is investigated which consists of a saucer-shaped hull, multi-vectored thrusters, and an under-slung nacelle. The design of this aerostat involves tradeoffs between conventional ai... A new concept stratospheric aerostat is investigated which consists of a saucer-shaped hull, multi-vectored thrusters, and an under-slung nacelle. The design of this aerostat involves tradeoffs between conventional airship and high altitude balloon. The sling connection simplifies structure design significantly, but brings challenges for dynamics analysis. Dynamics modeling for this aerostat is a kind of double-body problem with geometric constraint. Nonlinear dynamics model is established by considering the effects of under-slung nacelle. Oscillation behavior of this double-body system is superposed by a long-period oscillation of the hull and a short-period oscillation of the nacelle. The length of sling only influences the short-period oscillation but the mass ratio of nacelle to main body determines the stability of system. Finally, an envelope about mass ratio and maximal open loop forward thrust as well as speed is presented, where the system is stable. 展开更多
关键词 saucer-shaped AEROSTAT double-body under-slung DYNAMICS modeling
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Effects of Supplemented Shengmai San (SMS) on Blood Biochemistry and HSP72 Expression in Peripheral Blood of Flying-saucer Athletes before and after High Temperature Training
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作者 Jian Shen Feng Xu +1 位作者 Bin Jin Rongquan Zhang 《Journal of Integrative Medicine(双语)》 2020年第2期17-21,共5页
Objective:The purpose of this paper is to study the effects of supplemented Shengmai San on the expression of heat shock protein 72(HSP72)and blood biochemistry in peripheral blood of flying-saucer athletes before and... Objective:The purpose of this paper is to study the effects of supplemented Shengmai San on the expression of heat shock protein 72(HSP72)and blood biochemistry in peripheral blood of flying-saucer athletes before and after high temperature training,so as to provide experimental basis for enhancing thermal endurance and preventing heat disease of flying-saucer athletes with anti-heat disease drugs.Methods:24 flying-saucer athletes from Zhejiang province were selected and divided into two groups,including control group and traditional Chinese medicine group with 12 people in each group.Among them,those who did not drink supplemented Shengmai San were in the control group,while those who drank it were in the traditional Chinese medicine group.During summer training,high temperature training task was carried out for 2 weeks.Flying-saucer athletes in traditional Chinese medicine group were given supplemented Shengmai San before training every morning and afternoon.Peripheral venous blood of each group was extracted before experiment and 2 weeks later and lymphocyte HSP72 content,blood routine and biochemical indexes were determined respectively.Results:Before the experiment,there were no abnormal phenomenon blood routine,biochemical test value and HSP72 expression in the control group and the traditional Chinese medicine group.After comparison,there was no significant difference(P>0.05).After the high temperature training,the expression of HSP72 in the Chinese medicine group was significantly higher than that before the training and control group(P<0.05).There were significant differences in white blood cell count before and after the experiment(P<0.05).Conclusion:Taking supplemented Shengmai San can significantly increase expression of HSP72 in up-regulation of flying saucer athletes after thermal stimulation,thus enhancing thermal tolerance and preventing thermal diseases. 展开更多
关键词 Supplemented Shengmai San Flying saucer athletes Training of high temperature HSP72
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The Observation of Blood Biochemistry and HSP72 Expression Changing Rules in Peripheral Blood of Flying-saucer-athletes under High Temperature Training
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作者 Jian Shen Feng Xu +1 位作者 Bin Jin Rongquan Zhang 《Journal of Integrative Medicine(双语)》 2020年第2期8-11,共4页
Objective:To study the effect of training under high temperature on blood and heat shock protein 72(HSP72)expression of flying saucer athletes.Methods:The numbers of training group and control group are 30.Twenty-four... Objective:To study the effect of training under high temperature on blood and heat shock protein 72(HSP72)expression of flying saucer athletes.Methods:The numbers of training group and control group are 30.Twenty-four flying saucer athletes in Zhejiang province were selected and randomly divided into training group and control group,15 in each group.Peripheral venous blood of each group was taken before and after the experiment.The HSP72 content of lymphocyte,blood routine and biochemical indexes were measured respectively.Results:There was significant difference in white blood cell in training group count before and after the experiment(P<0.05).The expression of HSP72 and the white blood cell in training group was higher than that control group(P<0.05).Conclusions:Organism could be affected and turned to stress state due to training under high temperature.It is necessary to provide the safeguard for the flying saucer athletes under high temperature in order to prevent the damage. 展开更多
关键词 Flying saucer Athletes Blood routine experiment Biochemical index Heat shock protein 72 Training under high temperature
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Discoid meniscus:Treatment considerations and updates
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作者 Waleed Albishi Amjad Albaroudi +3 位作者 Abdulrahman M Alaseem Sarah Aljasser Ibrahim Alshaygy Abdullah Addar 《World Journal of Orthopedics》 2024年第6期520-528,共9页
A discoid meniscus is a morphological abnormality wherein the meniscus loses its normal‘C’shape.Although most patients are asymptomatic,patients might still present with symptoms such as locking,pain,swelling,or giv... A discoid meniscus is a morphological abnormality wherein the meniscus loses its normal‘C’shape.Although most patients are asymptomatic,patients might still present with symptoms such as locking,pain,swelling,or giving way.Magnetic resonance imaging is usually needed for confirmation of diagnosis.Based on a constellation of factors,including clinical and radiological,different approaches are chosen for the management of discoid meniscus.The purpose of this review is to outline the treatment of discoid meniscus,starting from conservative approach,to the different surgical options for this condition.The PubMed and Google Scholar databases were used for this review.Studies discussing the treatment of discoid meniscus from 2018 to 2023 were searched.Initially there were 369 studies retrieved,and after removal of studies using the exclusion criteria,26 studies were included in this review.Factors such as stability,presence of tear,and morphology can help with surgical planning.Many approaches have been used to treat discoid meniscus,where the choice is tailored for each patient individually.Postoperatively,factors that may positively impact patient outcomes include male sex,body mass index<18.5,age at symptom onset<25 years,and duration of symptoms<24 months.The conventional approach is partial meniscectomy with or without repair;however,recently,there has been an increased emphasis on discoid-preserving techniques such as meniscoplasty,meniscopexy,and meniscal allograft transplantation. 展开更多
关键词 Discoid meniscus saucerization Partial meniscectomy Meniscoplasty Meniscopexy Meniscal allograft transplantation ARTHROSCOPY KNEE
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边缘电磁驱动碟形涵道飞行器设计与性能分析
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作者 邹文炀 李嘉仪 +6 位作者 刘凯 张恒珲 王亦凡 王新林 刘铁让 陈吉昌 童明波 《南京航空航天大学学报》 CAS CSCD 北大核心 2024年第5期900-908,共9页
针对传统转轴转子电机难以为大尺寸桨叶提供大输出转矩的问题,设计了一种采用“边缘电磁驱动”的中型碟形涵道式飞行器。为验证设计合理性,并评估飞行器性能参数,对飞行器典型过载工况进行了结构强度仿真计算,对悬停和平飞姿态分别进行... 针对传统转轴转子电机难以为大尺寸桨叶提供大输出转矩的问题,设计了一种采用“边缘电磁驱动”的中型碟形涵道式飞行器。为验证设计合理性,并评估飞行器性能参数,对飞行器典型过载工况进行了结构强度仿真计算,对悬停和平飞姿态分别进行了气动数值模拟,并对优选电磁线圈构型进行了电磁力仿真计算。研究结果表明:飞行器边缘电磁驱动系统能输出3700 N·m的转矩,转矩密度33.76 N·m/kg,满足运行动力需求;计算得出该飞行器设计具备一吨级最大起飞质量的气动能力,结构强度满足典型过载工况下的强度要求,为中大型碟形飞行器的构型设计和驱动方案设计提供参考。 展开更多
关键词 飞行器设计 碟形涵道飞行器 共轴双旋翼 数值模拟 边缘电磁驱动
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矿用碟形托盘压缩变形及承载特性研究 被引量:2
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作者 潘立志 赵同彬 +2 位作者 邢明录 贾敬龙 付彦坤 《山东科技大学学报(自然科学版)》 CAS 北大核心 2023年第2期53-61,共9页
为阐明碟形托盘在巷道锚杆支护系统中的作用机理,采用室内试验与理论分析方法,研究了矿用碟形托盘的压缩变形过程与承载特性,分析了托盘尺寸参数对承载能力的影响。研究结果表明:碟形托盘的压缩变形过程分为整体协调变形阶段、拱部弯曲... 为阐明碟形托盘在巷道锚杆支护系统中的作用机理,采用室内试验与理论分析方法,研究了矿用碟形托盘的压缩变形过程与承载特性,分析了托盘尺寸参数对承载能力的影响。研究结果表明:碟形托盘的压缩变形过程分为整体协调变形阶段、拱部弯曲变形阶段、拱部渐进屈服阶段和拱部完全失效阶段;碟形托盘可按变形特点划分为压缩变形区域、扩张变形区域和翘曲变形区域,压缩变形区域是托盘的主要承载区域;碟形托盘拱部尺寸和形状会影响其承载能力,最大承载力随拱底圆周半径的增加而增大,随拱部高度的增大先增加后减小,且拱部径高比越接近1,托盘整体承载能力越强。 展开更多
关键词 锚杆支护 碟形托盘 压缩变形 变形区域 承载特性
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成都平原商周时期尖底盏研究
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作者 蒋辉 于孟洲 《考古与文物》 CSSCI 北大核心 2023年第1期52-62,共11页
本文通过对成都平原商周时期尖底盏系统的类型学分析,结合成都平原商周时期考古学遗存的阶段性变化,将尖底盏发展进程划分为二期四段,对成都平原尖底盏的起源、消亡及用途等相关问题进行了探讨,并以尖底盏为线索,考察了成都平原与关中... 本文通过对成都平原商周时期尖底盏系统的类型学分析,结合成都平原商周时期考古学遗存的阶段性变化,将尖底盏发展进程划分为二期四段,对成都平原尖底盏的起源、消亡及用途等相关问题进行了探讨,并以尖底盏为线索,考察了成都平原与关中西部、峡江地区的文化交流、人群迁徙等问题。 展开更多
关键词 成都平原 商周时期 尖底盏 相关研究
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浅议基于Java的PDF文档生成 被引量:1
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作者 崔永 王建新 《电脑知识与技术》 2011年第8X期5923-5924,共2页
介绍了目前Java项目中生成PDF文档使用的几种主要工具,并对它们进行了简单的分析,介绍了一种新的工具Flying Saucer并描述了其特性,通过实例介绍了如何使用Flying Saucer动态生成PDF文档。
关键词 JAVA PDF Flying saucer
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呼伦贝尔沙质草原碟形风蚀坑表面气流及其意义 被引量:22
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作者 王帅 哈斯 +1 位作者 张军 张萍 《中国沙漠》 CSCD 北大核心 2007年第5期745-749,共5页
呼伦贝尔沙质草原风蚀坑发育于宽单峰中能风况环境,是该区主要风沙地貌类型。对碟形坑表面气流的观测结果显示,气流进入风蚀坑后,在入风口扩散,风速开始降低至坑底达到最低;在坑后缘出风口汇集形成急流,风速剧增至坑后积沙顶部风速达到... 呼伦贝尔沙质草原风蚀坑发育于宽单峰中能风况环境,是该区主要风沙地貌类型。对碟形坑表面气流的观测结果显示,气流进入风蚀坑后,在入风口扩散,风速开始降低至坑底达到最低;在坑后缘出风口汇集形成急流,风速剧增至坑后积沙顶部风速达到最高值。风蚀坑后缘在风沙流的磨蚀作用下后退,风蚀坑顺风向扩展,同时此处较大的剪切风速和输沙率使大量来自坑内的沙物质沉积到坑后草地上呈扇状蔓延。呼伦贝尔沙质草原风蚀坑在来自西北、西和西南方向风的交替作用下,向东南、东和东北方向扩展而生成。随着风蚀坑深度和水平尺度的增加,最终可能沿强风能方向或合成输沙方向扩展成为大型的槽形坑。 展开更多
关键词 呼伦贝尔草原 碟形风蚀坑 表面气流 动力学
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一类新型飞行器复合控制研究 被引量:7
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作者 邓以高 鲍永平 +1 位作者 雷军委 顾文锦 《系统仿真学报》 EI CAS CSCD 北大核心 2005年第7期1531-1534,共4页
首次推导了基于质量控制和推力矢量控制的一类无尾无舵翼碟形飞行器的空间六自由度运动动力学方程。以纵向运动为例,对模型进行了合理的简化,进行了稳定性分析和控制器设计,给出了不同控制的仿真曲线。最后进行了飞行仿真研究,给出了六... 首次推导了基于质量控制和推力矢量控制的一类无尾无舵翼碟形飞行器的空间六自由度运动动力学方程。以纵向运动为例,对模型进行了合理的简化,进行了稳定性分析和控制器设计,给出了不同控制的仿真曲线。最后进行了飞行仿真研究,给出了六自由度飞行轨迹仿真曲线,证明了控制器设计的有效性,为深入探讨质量/推力矢量复合控制奠定了基础。 展开更多
关键词 质量控制 推力矢量控制 复合控制 模型 碟形飞行器
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一类碟型飞行器质量/推力矢量复合控制研究 被引量:8
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作者 邓以高 顾文锦 +1 位作者 赵红超 于进勇 《飞行力学》 CSCD 北大核心 2005年第3期28-31,36,共5页
推导了基于质量/推力矢量复合控制的一类碟型飞行器空间六自由度运动动力学方程。以纵向运动为例,对模型进行了合理简化,进行了稳定性分析和控制器设计,给出了某一特征点上质量控制、推力矢量控制、质量/推力矢量复合控制的仿真曲线,最... 推导了基于质量/推力矢量复合控制的一类碟型飞行器空间六自由度运动动力学方程。以纵向运动为例,对模型进行了合理简化,进行了稳定性分析和控制器设计,给出了某一特征点上质量控制、推力矢量控制、质量/推力矢量复合控制的仿真曲线,最后进行了纵向运动飞行仿真,给出纵向运动实际飞行轨迹和理想飞行轨迹的对比仿真曲线,证明了控制器设计的有效性。 展开更多
关键词 质量控制 推力矢量控制 复合控制 碟型飞行器
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一种新型波能发电装置的运动响应计算 被引量:6
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作者 史宏达 刘栋 刘臻 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第10期111-116,共6页
为分析碟形越浪式波能发电装置初步设计方案的合理性和不足,应用三维势流理论和波浪的辐射-衍射理论,结合水动力分析软件AQWA,计算在规则波浪作用下装置浮体6个自由度上运动的响应幅值算子(RAOs),考虑不规则波浪、风、流载荷的共同作用... 为分析碟形越浪式波能发电装置初步设计方案的合理性和不足,应用三维势流理论和波浪的辐射-衍射理论,结合水动力分析软件AQWA,计算在规则波浪作用下装置浮体6个自由度上运动的响应幅值算子(RAOs),考虑不规则波浪、风、流载荷的共同作用,对装置在工作海况和恶劣海况下的运动响应进行数值模拟分析,得到其时间历程结果。结果表明:装置结构外形设计合理,装置在其锚链张力腿锚泊系统定位下,运动响应满足工作稳定性要求和安全性要求。 展开更多
关键词 碟形装置 锚链张力腿 AQWA 响应幅值算子 运动响应
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碟形飞行器复合控制分配策略的设计与分析 被引量:7
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作者 王军生 徐胜红 刘海波 《战术导弹技术》 北大核心 2006年第3期69-73,共5页
针对碟形飞行器变质量矩/推力矢量复合控制系统,设计了以输出误差为参考量的两类复合控制分配策略.仿真研究表明,两类控制分配策略均实现了不同控制方式的优势互补,能达到较好的控制性能.此外,对两类控制分配策略的性能进行了分析比较.
关键词 碟形飞行器 复合控制 分配策略 鲁棒性
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基于模糊理论的碟形飞行器复合控制分配策略 被引量:7
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作者 施建洪 徐胜红 禹继顺 《海军航空工程学院学报》 2005年第5期513-516,共4页
针对碟形飞行器变质量矩/推力矢量复合控制系统,研究了以输出误差和误差变化率为参考量及基于模糊理论的控制分配策略.仿真表明,这一设计能够实现两种控制方式的优势互补,达到了良好的控制性能.
关键词 碟形飞行器 复合控制 模糊理论 分配策略
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针对一类无人飞行器复合控制的控制分配策略 被引量:2
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作者 冯国虎 章大勇 +3 位作者 张新立 罗兵 庹洲慧 肖正良 《宇航学报》 EI CAS CSCD 北大核心 2008年第4期1302-1307,共6页
针对一类无人飞行器即碟式飞行器静不稳定的特点,选择了变质量矩/推力矢量复合控制方法。为了解决复合控制中的控制分配问题,提出了两种分配策略:基于误差的非线性分配策略和基于能量的最优分配策略。这两种分配策略的设计和控制律设计... 针对一类无人飞行器即碟式飞行器静不稳定的特点,选择了变质量矩/推力矢量复合控制方法。为了解决复合控制中的控制分配问题,提出了两种分配策略:基于误差的非线性分配策略和基于能量的最优分配策略。这两种分配策略的设计和控制律设计相分离,控制律确定总的控制量,分配由单独的环节实现。仿真表明,不考虑控制量受限时,这两种设计都实现了变质量矩控制和推力矢量控制的优势互补,达到了良好的控制性能;考虑控制量受限时,相对于非线性分配策略,最优分配策略避免了控制量受限的影响。 展开更多
关键词 碟式飞行器 复合控制 控制分配 控制受限
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碟形飞行器复合控制的非线性分配策略研究 被引量:7
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作者 徐胜红 盛忠培 顾文锦 《弹箭与制导学报》 CSCD 北大核心 2006年第1期8-11,共4页
针对碟形飞行器变质量矩/推力矢量复合控制系统,研究了以输出误差为参考量的非线性控制分配策略。仿真表明,这一设计实现了两种控制方式的优势互补,又避免了强制切换控制方式所引起的控制扰动,达到了良好的控制性能。
关键词 碟形飞行器 复合控制 分配策略
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基于退火递归神经网络的极值搜索优化算法求解一类碟式飞行器平衡状态 被引量:4
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作者 胡云安 左斌 李静 《兵工学报》 EI CAS CSCD 北大核心 2008年第3期341-347,共7页
针对一类碟式飞行器平衡状态的基本特征及现有的优化平衡状态算法如单纯形算法、混合遗传算法所存在的随机性大、收敛速度较慢等缺点,提出了一种新颖的基于退火递归神经网络(ARNN)的极值搜索优化算法。将碟式飞行器的配平问题转化为所... 针对一类碟式飞行器平衡状态的基本特征及现有的优化平衡状态算法如单纯形算法、混合遗传算法所存在的随机性大、收敛速度较慢等缺点,提出了一种新颖的基于退火递归神经网络(ARNN)的极值搜索优化算法。将碟式飞行器的配平问题转化为所设计的代价函数(CF)求解问题,利用所提出的退火递归神经网络极值搜索优化算法求解出在多种定常飞行中碟式飞行器的平衡状态。在相同的仿真环境中,仿真结果对比说明ARNN极值搜索优化算法较混合遗传算法具有稳定性好、精确度高、收敛速度快等优点。 展开更多
关键词 自动控制技术 退火递归神经网络 极值搜索算法 碟式飞行器 平衡状态
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摩擦片精冲成形实验研究 被引量:2
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作者 汤建云 黄尚宇 +2 位作者 胡建华 施键 周开华 《锻压技术》 CAS CSCD 北大核心 2006年第3期43-45,共3页
提出采用精冲工艺进行车辆摩擦片的生产。根据摩擦片的结构特点、加工硬化、应力分布及材料等,讨论了精冲成形和热处理的技术难点,制定了摩擦片的精冲工艺;然后再根据实验过程中获得的齿顶圆、齿根圆及碟形量变化曲线,分析其产生原因并... 提出采用精冲工艺进行车辆摩擦片的生产。根据摩擦片的结构特点、加工硬化、应力分布及材料等,讨论了精冲成形和热处理的技术难点,制定了摩擦片的精冲工艺;然后再根据实验过程中获得的齿顶圆、齿根圆及碟形量变化曲线,分析其产生原因并提出了解决成形过程中变形问题的措施,已制造出符合质量要求的摩擦片精冲件。 展开更多
关键词 摩擦片 精冲 蝶形 淬火
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