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Search Results: 1 - 10 of 115879 matches for " 周前祥 "
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载人航天器人—机系统虚拟仿真技术关键问题的探讨

科技导报 , 2003,
Abstract: 虚拟现实(VirtualReality,VR)本质上就是利用计算机产生一个让人如同身临其境的以自然的视、听、触、嗅等功能感觉到的三维空间环境,从而可以用他具有的能力和方法,对这个生成的“客观世界”进行观察、分析、操作和控制。[1,2].与通常意义上的多媒体相比,该技术将人、计算机间的信息交互通道由二维(声音和图像)扩大到多维(声音、图像和人的其它功能感觉),并且显示的图像由平面变为立体,因此,可以说它是多媒体技术深层次进步的结果。
航天虚拟现实仿真技术的研究进展
,曲战胜
科技导报 , 1998,
Abstract: 航天飞行是一项耗资巨大、变量参数很多、非常复杂的系统工程,保证其安全、可靠是进行航天器设计时必须考虑的重要问题。因此。利用仿真技术的经济、安全以及可重复性等特点,进行飞行任务或操作的模拟,来代替某些费时、费力、费钱的真实试验或者无法开展的真实试验,最终找到提高航天员工作效率或航天器系统可靠性等的设计方法,就成为确保航天器安全可靠的技术途径[1、2].研究的意义虚拟现实(VirtualReality,简称VR)是一种可以创建和体验虚拟世界(VirtualWorld)的计算机系统。
基于sEMG信号的操作者上肢肌肉施力疲劳评价模型研究
, 谌玉红, 马超, 郑晓慧
中国科学 生命科学 , 2011,
Abstract: 为评价操作者完成施力操作后上肢肌肉疲劳状态,提出了一种基于上肢肱二头肌的sEMG信号-疲劳程度主观感受的肌肉施力疲劳评价方法.为此,设置不同的拉/伸操作力,选取13名青年男性志愿者参加测试,记录其上肢肱二头肌操作至疲劳状态下的表面肌电信号sEMG;对于上肢肱二头肌局部疲劳的主观感受的评分,则采用通用的Borg量表来分级,由受试者完成操作后进行问卷而获得.然后,运用1/3倍频程分析方法对sEMG进行频域处理后,完成了sEMG-Borg分值的曲线拟合,得出上肢肌肉疲劳评价模型.根据数据分析结果,建立的二次曲线评价模型最为理想,它将为监测实际操作任务时人的疲劳状态并进行操作任务设计与分析提供依据与手段.
不同光谱与空间分辨率遥感图像融合方法的理论研究
,敬忠良,姜世忠
遥感技术与研究 , 2003,
Abstract: 多源遥感图像的融合处理是提高已获取同一目标影像的光谱和空间分辨率的重要手段,它可以增强多重数据分析处理能力,为大规模遥感应用研究提供一个良好的基础。对目前国内外现有的理论研究方法作了总结,将其分为像素级、特征级和决策级融合3大类型,分别进行了详细的阐述,同时引用具体研究成果对一些方法作了对比。最后,提出了该领域未来的主要研究与发展方向以供讨论。 
虚拟现实技术及其在工效学研究中的应用
姜国华,陈善广,,王春慧,张宜静
计算机系统应用 , 2001,
Abstract: 虚拟现实是一种可以创建和和体验虚拟世界的计算机系统,作为新兴人机交互技术有非常明显的技术特点和广泛的应用范围。本文详细阐述了虚拟现实系统的体系组成,技术现状及其在国内外工效学领域的研究进展,并结合具体实验研究介绍了作者正在进行的研究工作。
吡啶乙炔苯甲腈类化合物的制备有机化学
汪志勇,,姜超,存六,郭庆
有机化学 , 2001,
Abstract: 对苯乙炔和吡啶乙炔类化合物的Heck反应进行了较全面的论述和仔细的研究,发现溶剂对催化体系有重要的影响。并成功的改进了一个Pd催化偶合反应。将该反应用于吡啶乙炔苯甲腈类化合物的合成。四个新的吡啶乙炔苯甲腈化合物被首次合成出来,从而为该类化合物的合成提供了一个有效而又方便的方法。
大别造山带北部铁佛寺早古生代同碰撞型花岗岩:地球化学和年代学证据
张金阳,马昌,佘振兵,,红升
中国科学 地球科学 中国科学 地球科学 , 2007,
Abstract: ?出露于大别山西北部信阳市附近的铁佛寺岩体侵入元古代秦岭群,通过锆石SHRIMPU-Pb法测得该岩体年龄为(436±11)Ma.铁佛寺钾长花岗岩和二长花岗岩暗色矿物含量极少,可见白云母,SiOM2含量较高且变化范围很窄,K2O/Na2O比值很高,属高钾钙碱性系列,ACNK>1.1,为强过铝质,FeO,Fe2O3及MgO含量很低.岩石总体上相对富集大离子亲石元素,亏损高场强元素.岩石稀土元素及微量元素表现出三种不同的特征,第Ⅰ类岩石Eu为弱负异常,(La/Yb)N比值最大,稀土元素总量(ΣREE),Rb/Sr及Rb/Ba比值中等;第Ⅱ类岩石Eu为中等负异常,(La/Yb)N比值最小,SREE,Rb/Sr及Rb/Ba比值最大;第Ⅲ类岩石Eu表现正异常,(La/Yb)N比值中等,SREE,Rb/Sr及Rb/Ba比值最小.全岩εNd(440Ma)集中在-8.8~-9.9之间,Nd模式年龄为2.0Ga左右,与秦岭群副片麻岩相似.综合分析表明铁佛寺花岗岩为壳源S型同碰撞花岗岩,Ⅰ类花岗岩浆形成于秦岭群副片麻岩低程度部分熔融,Ⅱ类花岗岩浆是由Ⅰ类花岗岩浆发生斜长石结晶分异形成,而III类花岗岩可能与混杂了结晶分异的斜长石堆晶有关.铁佛寺花岗岩形成于华北板块与扬子板块陆-陆碰撞有关的构造环境.
基于EEG的脑力疲劳特征研究
Mental fatigue characteristics based on EEG analysis

范晓丽,牛海燕,,柳忠起
- , 2016, DOI: 10.13700/j.bh.1001-5965.2015.0428
Abstract: 摘要 模拟飞行员在飞行过程中监视仪表信息的过程,分析脑电(EEG)随脑力疲劳变化的特点及规律,从而为后期对抗脑力疲劳提供科学根据。通过设计2级不同难度的视觉监控任务分别诱发脑力疲劳,采用多种方法相结合进行研究,比较EEG参数(δ、θ、α、β、(α+θ)/β、α/β、(α+θ)/(α+β)和 θ/β)在任务前后的变化情况。结果表明:从正常到疲劳状态,额区、中央区、顶区和枕区的α波相对能量显著增加(P < 0.05);前额区、侧额区、后颞区以及枕区的β波相对能量显著降低(P < 0.05);δ波和θ波相对能量变化未达到显著性差异(均有P > 0.05);参数(α+θ)/β、α/β、(α+θ)/(α+β)和θ/β在除颞区外的各脑区都显著增大(P < 0.05);在颞区,只有α/β在疲劳前后增加明显(P < 0.05);与较高难度的任务比较,低难度任务中的各EEG参数变化较为明显。因此,除δ波和θ波以外的其他特征参数被证实在特定的脑区域可以作为衡量脑力疲劳的潜在指标,同时可以验证适当地增加任务难度可以在某种程度上对抗脑力疲劳的产生。
Abstract:By simulating the process of pilots monitoring instrument information during flight,the change characteristics of electroencephalogram (EEG) waves along with mental fatigue were analyzed,which will provide scientific bases for future development of countermeasure to fatigue.Two visual detection tasks of different difficulties were designed to induce fatigue respectively,and many measurements were combined to study the EEG characteristics of fatigue.The EEG parameters [δ,θ,α,β,(α+θ)/β,α/β,(α+θ)/(α+β),θ/β] at the beginning and end sections of the task were compared and analyzed.The results show that there is a significant increase in α activity in the frontal,central,parietal and occipital lobes(P < 0.05),and a decrease in the β activity in the pre-frontal,inferior frontal,posterior temporal and occipital lobes(P < 0.05); there is no significant difference in δ rhythm and θ rhythm in any brain region(all in P > 0.05); The four formulas increase significantly in all brain regions except the temporal(P < 0.05),where only α/β changes clearly(P < 0.05); compared with the task with higher difficulty,the parameters in the task of lower difficulty change more obviously.Therefore,all these characteristic parameters in specific brain regions except for δ and θ can be considered as possible indicators for mental fatigue.It was also verified that adding right amount of task difficulty could counter mental fatigue.
基于视觉搜索的飞机显示界面设计原则
Principle of plane display interface design based on visual search

范晓丽,,柳忠起,解芳
- , 2015, DOI: 10.13700/j.bh.1001-5965.2014.0087
Abstract: 摘要 对飞行员在飞行中通过视觉搜索监视各种仪表信息的过程进行研究,探索时间压力和搜索难度两个因素对视觉搜索绩效的影响,从而为飞机座舱显示界面的工效学设计提供科学依据.设计视觉搜索程序来模拟飞机显示界面,并通过预实验确定时间压力水平和搜索难度水平的典型分级范围,在此基础上进行正式实验并记录反应正确率和反应时间.采用SPSS 19.0对实验结果进行双因素分析、简单效应、回归分析等,得到如下结论:不同水平的时间压力和搜索难度对反应正确率的影响具有显著性差异;不同水平的搜索难度对反应时间的影响具有显著性差异,并且在一定条件下反应时间和干扰项数目成线性递增关系;在保证较高正确率的状态下,即在人的认知能力范围之内,不同的时间压力水平对反应时间的影响没有显著性差异.因此,在飞机座舱显示界面视觉搜索的工效学设计中,要将时间压力和搜索难度进行最佳匹配才能取得较好的工作绩效.
Abstract: Pilots monitor all kinds of instrument information by visual searching during flight. This process was studied to explore the effects of time pressure and search difficulty on visual searching, aiming to provide scientific basis for the ergonomic design of display interface of aircraft cockpit. A visual searching program was designed to simulate the display interface. Before conducting formal experiment, the classified ranges of time pressure and searching difficulty were evaluated by pre-experiment. Using SPSS 19.0, analyses such as double factor variance analysis, simple main effect, and regression analysis were conducted on the response correct rate and response time obtained by the formal experiment. The following conclusions were obtained, different levels of time pressure and search difficulty all have significant effect on the response accurate rate; search difficulty has obvious effect on the response time which has a linearly increasing relationship with distractor number; under high correct rate situation, that is within the human cognitive abilities, time pressure haven't such effect on the response time. In ergonomical study of display interface in plane cockpit, good match of time pressure and searching difficulty could obtain better searching performance.
基于因果关系的步枪射击pre-shot阶段脑电网络分析
Efficient connectivity analysis of electroencephalogram in the pre-shot phase of rifle shooting based on causality method

张立伟,,柳忠起,饶永红
- , 2018, DOI: 10.7507/1001-5515.201705078
Abstract: 大脑皮层网络有向功能连通性是理解大脑组织行为活动方式的关键。本文探索步枪射击任务中射手大脑网络在脑电信号不同节律下的有向功能连通性,为加速步枪射击训练方法的研究提供神经科学方面的依据。采用扩展概率性因果方法分析步枪射击专家和新手在射击准备(pre-shot)阶段大脑皮层的有效定向功能连接。结果表明,额区、额-中、中央区、顶区和枕区在射击过程中都被激活,并且大脑右半球功能连接数量明显多于左半球。在 pre-shot 阶段,与专家相比较,新手大脑皮层网络参与活动的脑区明显增多、网络节点间的连接强度更大、全局效率值较低。这些结果间接地证明了新手需要更努力地协调更多的资源来完成任务,这与专家功能性脑组织的“神经效率”假说一致。
The directed functional connectivity in cerebral cortical is the key to understanding the pattern of the behavioral tissue. This process was studied to explore the directed functional network of rifle shooters at cerebral cortical rhythms from electroencephalogram (EEG) data, aiming to provide neurosciences basis for the future development of accelerating rifle skill learning method. The generalized orthogonalized partial directed coherence (gOPDC) algorithm was used to calculate the effective directed functional connectivity of the experts and novices in the pre-shot period. The results showed that the frontal, frontal-central, central, parietal and occipital regions were activated. Moreover, the more directed functional connections numbers in right hemispheres were observed compared to the left hemispheres. Furthermore, as compared to experts, novices had more activated regions, the stronger strength of connections and the lower value of the global efficiency during the pre-shot period. Those indirectly supported the conclusion that the novices needed to recruit more brain resources to accomplish tasks, which was consistent with " neural efficiency” hypothesis of the functional cerebral cortical in experts.
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