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高斯束状波斜程传输的大气湍流效应 被引量:10
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作者 范承玉 《量子电子学报》 CAS CSCD 1999年第6期519-525,共7页
利用Mellin变换技术,给出了弱起伏范围内Gauss准直光束的对数振幅起伏方差、波束扩展半径和漂移角方差的表达式,利用昆明实测的近地层大气湍流强度的高度分布,计算了多种靶标高度斜程传输情况下波束的对数振幅起伏方差、... 利用Mellin变换技术,给出了弱起伏范围内Gauss准直光束的对数振幅起伏方差、波束扩展半径和漂移角方差的表达式,利用昆明实测的近地层大气湍流强度的高度分布,计算了多种靶标高度斜程传输情况下波束的对数振幅起伏方差、扩展半径和漂移角. 展开更多
关键词 对数振幅起伏 波束扩展 漂移 光波 大气湍流效应
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Revised apparent polar wander path of the Yangtze Block and its tectonic implications 被引量:6
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作者 吴汉宁 朱日祥 +2 位作者 白立新 郭斌 吕建军 《Science China Earth Sciences》 SCIE EI CAS 1998年第S2期78-90,共13页
Paleomagnetic data, during the Phanerozoic obtained in the last 20 years in the Yangtze Block (YZB), are critically reviewed. A new apparent polar wander path (APWP) for the YZB is constructed by selected poles with o... Paleomagnetic data, during the Phanerozoic obtained in the last 20 years in the Yangtze Block (YZB), are critically reviewed. A new apparent polar wander path (APWP) for the YZB is constructed by selected poles with objective reliable criteria, with a goal of placing constraints on the models of the formation and subsequent deformation and reconstructing the tectonic evolution history of this region 展开更多
关键词 PALEOMAGNETISM APPARENT POLAR wander PATH YANGTZE Block.
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The influence of Cretaceous paleolatitude variation of the Tethyan Himalaya on the India-Asia collision pattern 被引量:6
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作者 ZHANG Ye HUANG BaoChun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第6期1057-1066,共10页
Identifying when, where, and how India and Asia collided is a prerequisite to better understand the evolution of the Himalayan-Tibetan Plateau. Whereas with essentially the same published paleomagnetic data, a large r... Identifying when, where, and how India and Asia collided is a prerequisite to better understand the evolution of the Himalayan-Tibetan Plateau. Whereas with essentially the same published paleomagnetic data, a large range of different India-Asia collision models have been proposed in the literature. Based upon the premise of a northwards-moving Indian plate during the Cretaceous times, we analyze the significant variations in relative paleolatitude produced by a nearly 90° counterclockwise(CCW)rotation of the plate itself during the Cretaceous. Interestingly, recent studies proposed a dual-collision process with a Greater India basin or post-Neo-Tethyan ocean for the India-Asia collision, mainly in the light of divergent Cretaceous paleolatitude differences of the Tethyan Himalaya between the observed values and expected ones computed from the apparent polar wander path of the Indian plate. However, we find that these varied paleolatitude differences are mainly resulted from a nearly 90° CCW rotation of a rigid/quasi-rigid Greater Indian plate during the Cretaceous. On the other hand, when the Indian craton and Tethyan Himalaya moved as two individual blocks rather than a united rigid/quasi-rigid Greater Indian plate before the India-Asia collision, current available Cretaceous paleomagnetic data permit only multiple paleogeographic solutions for the tectonic relationship between the Indian plate and the Tethyan Himalayan terrane. We therefore argue that the tectonic relationship between the Indian plate and the Tethyan Himalayan terrane cannot be uniquely constrained by current paleomagnetic data in the absence of sufficient geological evidence, and the so-called Greater India basin model is just one of the ideal scenarios. 展开更多
关键词 India-Asia collision model Tethyan Himalaya Apparent polar wander (APW) path Paleolatimde Vertical-axis rotation
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无奈与无依的漂泊——蒋捷词的情感主旋律 被引量:5
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作者 张静 《台州学院学报》 2005年第2期24-27,共4页
宋元易代的社会动荡,使蒋捷陷入国破家亡的境地;“抱节终身”的气节,使他义不仕元。无家可归,无处可依,使他只能在漂泊中度过余生,在漂泊中开始了对社会人生的深刻思索。他的亡国之痛,忧生之嗟,人生空寞之叹都是围绕着漂泊展开的。无奈... 宋元易代的社会动荡,使蒋捷陷入国破家亡的境地;“抱节终身”的气节,使他义不仕元。无家可归,无处可依,使他只能在漂泊中度过余生,在漂泊中开始了对社会人生的深刻思索。他的亡国之痛,忧生之嗟,人生空寞之叹都是围绕着漂泊展开的。无奈与无依的漂泊是蒋捷词的情感主旋律。 展开更多
关键词 蒋捷 无奈 无依 情感 漂泊
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Removal of baseline wander from ECG signal based on a statistical weighted moving average filter 被引量:3
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作者 Xiao HU Zhong XIAO NiZHANG 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2011年第5期397-403,共7页
Baseline wander is a common noise in electrocardiogram (ECG) results.To effectively correct the baseline and to preserve more underlying components of an ECG signal,we propose a simple and novel filtering method based... Baseline wander is a common noise in electrocardiogram (ECG) results.To effectively correct the baseline and to preserve more underlying components of an ECG signal,we propose a simple and novel filtering method based on a statistical weighted moving average filter.Supposed a and b are theminimum and maximum of all sample values within a moving window,respectively.First,the whole region [a,b] is divided into M equal sub-regions without overlap.Second,three sub-regions with the largest sample distribution probabilities are chosen (except M<3) and incorporated into one region,denoted as [a 0,b 0 ] for simplicity.Third,for every sample point in the moving window,its weight is set to 1 if its value falls in [a 0,b 0 ];otherwise,its weight is 0.Last,all sample points with weight 1 are averaged to estimate the baseline.The algorithm was tested by simulated ECG signal and real ECG signal from www.physionet.org.The results showed that the proposed filter could more effectively extract baseline wander from ECG signal and affect the morphological feature of ECG signal considerably less than both the traditional moving average filter and wavelet package translation did. 展开更多
关键词 ECG signal Baseline wander Morphological feature Moving average filter Wavelet package translation
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从庄子之“游”到道教“游仙”的审美意蕴 被引量:1
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作者 阳淼 田晓膺 《海南大学学报(人文社会科学版)》 CSSCI 2007年第1期85-89,共5页
“游”贯穿于《庄子》。“游”的过程是体道的过程,亦是审美的过程。道教心目中的至大至美的精神境界,可以通过“游”来获得。“游”之游,是指进入“游”的审美状态;“游”之观,是指审美途径;“游”之化,是指审美境界和归属。而极具道... “游”贯穿于《庄子》。“游”的过程是体道的过程,亦是审美的过程。道教心目中的至大至美的精神境界,可以通过“游”来获得。“游”之游,是指进入“游”的审美状态;“游”之观,是指审美途径;“游”之化,是指审美境界和归属。而极具道教色彩的“游”之仙,是在“游”之化的基础上,人为突破形体在“游”中的局限所做的一种努力,从而使人达到在心灵和形体上的真正的逍遥“游”,使道教意义上的“游”,具备了审美与宗教的两重意义。 展开更多
关键词 逍遥 游仙
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Paleomagnetic results of Paleozoic and Mesozoic rocks from Xingshan-Zigui section in Hubei Province, South China 被引量:3
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作者 吴汉宁 朱日祥 +3 位作者 白立新 邢建孝 赵永新 杨革联 《Science China Earth Sciences》 SCIE EI CAS 1999年第2期182-194,共13页
The paleomagnetic reconnaissance study of the Paleozoic and Mesozoic sedimentary rocks from the Yangtze Block (YZB) was made to conduct the Apparent Polar Wander Path (APWP) of the YZB during the Phanerozoic. A total ... The paleomagnetic reconnaissance study of the Paleozoic and Mesozoic sedimentary rocks from the Yangtze Block (YZB) was made to conduct the Apparent Polar Wander Path (APWP) of the YZB during the Phanerozoic. A total of 825 samples from 84 sites were collected from a continuous section along the Xiangxi River valley in Xingshan and Zigui counties in Hubei Province, northern margin of the YZB. Stepwise thermal/alternating demagnetization isolated well defined characteristic magnetization (ChRM) at a higher temperature in most of the samples, and relatively thermal stability and high coercivity were revealed from these samples. All the ChRMs can pass the fold and/or reversal tests, suggesting that they are probably primary. Therefore, new pole positions are presented for the YZB. 展开更多
关键词 PALEOMAGNETISM APPARENT Polar wander Path PALEOZOIC MESOZOIC Yangtze Block.
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世纪之交的漂流与回归——谈当代日本电影中的“无国界流派” 被引量:4
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作者 白娟娟 《山东教育学院学报》 2006年第2期103-104,125,共3页
作为亚洲最大的电影市场,日本电影的发展总是能够引起亚洲地区的普遍关注并引领电影发展的潮流。新旧世纪之交,日本电影中出现了一种无国界世界公民的思想倾向,著名电影学者四方田犬彦将其称之为“无国界流派”。它在电影中的表现主要... 作为亚洲最大的电影市场,日本电影的发展总是能够引起亚洲地区的普遍关注并引领电影发展的潮流。新旧世纪之交,日本电影中出现了一种无国界世界公民的思想倾向,著名电影学者四方田犬彦将其称之为“无国界流派”。它在电影中的表现主要体现在“无家可归的漂流感”、“寻找自我的旅程”和“少数民旅寻求身份的认同”等三个方面。 展开更多
关键词 无国界流派 日本电影 漂流 回归
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The paleomagnetism and geological significance of Meso-proterozoic dyke swarms in the central North China Craton 被引量:4
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作者 侯贵廷 李江海 +2 位作者 钱祥麟 张宝兴 H.C.Halls 《Science China Earth Sciences》 SCIE EI CAS 2001年第2期185-192,共8页
The Mesoproterozoic mafic dyke swarms are extensively distributedin the central North China Craton(NCC) including North Shanxi, Wutai and Lüliang areas, which are not deformed and metamorphic but high magnetic, s... The Mesoproterozoic mafic dyke swarms are extensively distributedin the central North China Craton(NCC) including North Shanxi, Wutai and Lüliang areas, which are not deformed and metamorphic but high magnetic, so the dyke swarms become the mark to compare the high meta-morphic rock areas in magnetism. Based on the analysis of paleomagnetism of mafic dyke swarms in North Shanxi, Wutai and Lüliang areas, NCC inclined southward about 18° so that North Shanxi lifted up and rotated 10° left to Wutai area. The dyke swarms in Lüliang developed later than in North Shanxi and Wutai area. The NNW-trending and WNW-trending dyke swarms developed in Lüliang while the North China Plate moved northward consistently so that the paleomagnetism of dyke swarms in Lüliang is greatly different from North Shanxi and Wutai area. 展开更多
关键词 Mesoproterozoic mafic dyke swarms PALEOMAGNETISM magnetic inclination magnetic declination APPARENT polar wander path
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虚室生白:《庄子》的心隐与心隐空间
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作者 潘文文 张艳艳 《汕头大学学报(人文社会科学版)》 2024年第3期53-60,95,共9页
《庄子》隐逸思想以心隐为本,是学界的主流看法,但心隐的空间属性却常被淡化,故此,清晰辨析《庄子》心隐空间的内涵、表现形式与实现途径就尤为必要。《庄子》的心隐空间是葆有生命本性的心灵空间,指涉身心一如的生命体对道境的冥契,心... 《庄子》隐逸思想以心隐为本,是学界的主流看法,但心隐的空间属性却常被淡化,故此,清晰辨析《庄子》心隐空间的内涵、表现形式与实现途径就尤为必要。《庄子》的心隐空间是葆有生命本性的心灵空间,指涉身心一如的生命体对道境的冥契,心隐空间具象显现为“至人之游”和“至德之世”两种时空转化形式,其实现途径主要是“心斋”与“坐忘”的道家式身体修炼工夫,从而实现“虚室生白”,获得“虚己以游世”的在世空间体验。 展开更多
关键词 心隐 心隐空间
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在异乡浪游的桂冠诗人--美籍华人张错的诗歌艺术 被引量:4
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作者 饶芃子 朱桃香 《中国比较文学》 CSSCI 北大核心 2008年第3期77-84,125,共8页
美国华裔诗人张错有着两岸三地成长经历,近半个世纪来他在大洋西岸不断书写蕴涵古词古韵的自由体现代诗歌,以他乡飘泊者和浪游人的形象千回百转地抒发失却家国身份的愁苦。他的诗歌常于咏物中表达伤感,考古中追问历史的无常,其发展总体... 美国华裔诗人张错有着两岸三地成长经历,近半个世纪来他在大洋西岸不断书写蕴涵古词古韵的自由体现代诗歌,以他乡飘泊者和浪游人的形象千回百转地抒发失却家国身份的愁苦。他的诗歌常于咏物中表达伤感,考古中追问历史的无常,其发展总体经历了三个阶段:从年少之浪漫青涩到中年的"台湾经验"和凛冽情怀,再到淡泊宁静的沧海桑田心境,而其中又以飘泊和浪游情绪为最。 展开更多
关键词 张错 飘泊 浪游 台湾地区 回归
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杜甫“漂泊诗”的悲剧主题 被引量:1
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作者 钟晨音 《伊犁教育学院学报》 2003年第4期52-55,共4页
杜甫是中国诗歌史上第一个大量集中使用"漂(飘)泊"这一词的诗人,在其"漂泊西南"时期,他的诗歌创作出现了大量表现"漂泊感"的词语与意象。在这些"漂泊诗"中,杜甫赋予了它们重大的政治和社会内容... 杜甫是中国诗歌史上第一个大量集中使用"漂(飘)泊"这一词的诗人,在其"漂泊西南"时期,他的诗歌创作出现了大量表现"漂泊感"的词语与意象。在这些"漂泊诗"中,杜甫赋予了它们重大的政治和社会内容,表达了诗人报国无望的哀伤,浓厚的思乡情结,疾病缠身的痛楚等多重悲剧主题。 展开更多
关键词 漂泊 政治 社会 悲剧主题
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SDH系统E1接口定时的高质量恢复 被引量:2
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作者 王旭 王一超 冯重熙 《电子学报》 EI CAS CSCD 北大核心 2000年第7期40-44,共5页
SDH传输网中由指针调整带来的低频抖动和漂移已经成为SDH传输网与其它传输网互通的障碍 .这一问题可以通过在SDH系统的边界支路输出口处采用极低带宽的锁相环对SDH网络指针调整带来的抖动和漂移进行平滑来得到改善和解决 .本文介绍了一... SDH传输网中由指针调整带来的低频抖动和漂移已经成为SDH传输网与其它传输网互通的障碍 .这一问题可以通过在SDH系统的边界支路输出口处采用极低带宽的锁相环对SDH网络指针调整带来的抖动和漂移进行平滑来得到改善和解决 .本文介绍了一种捕捉速度快、带宽窄、适合于多支路大规模集成的用于SDH系统E1支路接口的二阶全数字锁相环路 . 展开更多
关键词 接入网 同步数字系列 锁相环 抖动 漂移 传输网
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大气湍流中孔径限制下高斯光束的传播特性 被引量:2
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作者 田芃 元秀华 陈松 《光学与光电技术》 2006年第6期42-45,共4页
在扩展Huygens-Fresnel原理和Rytov近似的基础上,得到了孔径限制下湍流大气中高斯光束平均光强的积分表达式,利用数值模拟方法分析了轴上和接收面上平均光强的分布,并得到了波阵面半径、传播距离、湍流强度和波长与平均光强的关系曲线... 在扩展Huygens-Fresnel原理和Rytov近似的基础上,得到了孔径限制下湍流大气中高斯光束平均光强的积分表达式,利用数值模拟方法分析了轴上和接收面上平均光强的分布,并得到了波阵面半径、传播距离、湍流强度和波长与平均光强的关系曲线图。结果表明在湍流大气中波长、传播距离、发射孔径和波阵面半径的改变会引起平均光强重心的漂移,传播距离增加会导致光束的展宽。 展开更多
关键词 大气湍流 高斯光束 衍射 扩展Huygens—Fresnel原理 漂移
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广州市流浪精神病患者不同护送方式入院的临床对照研究 被引量:3
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作者 张献强 朱艳玲 《中国社区医师(医学专业)》 2011年第19期34-35,共2页
目的:探讨广州市不同部门护送入院的流浪精神病患者的临床表现的差异。方法:用自编《流浪精神病人般情况调查表》对2010年6月1日~2010年12月31日收治的流浪精神病人进行回顾性研究,按护送入院的部门分为公安组和民政组,各组随机抽取20... 目的:探讨广州市不同部门护送入院的流浪精神病患者的临床表现的差异。方法:用自编《流浪精神病人般情况调查表》对2010年6月1日~2010年12月31日收治的流浪精神病人进行回顾性研究,按护送入院的部门分为公安组和民政组,各组随机抽取200例病人进行对照研究。结果:两组病人在发现方式、入院表现、既往精神病史、伴躯体疾病、住院时间、出院方式等方面有明显差异(P<0·01)。结论:不同护送部门入院的流浪精神病患者临床表现有差异。 展开更多
关键词 流浪 精神病患者 临床表现
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门式斗轮机尾车胶带跑偏检测装置存在问题及改造
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作者 任俊斌 刘俊宏 《能源与节能》 2011年第6期87-88,共2页
叙述了造成尾车胶带跑偏检测装置难以起到保护作用的各种原因,提出了解决此问题的改造措施。
关键词 尾车胶带 跑偏 跑偏检测装置
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PALEOMAGNETISM OF THE LATE CRETACEOUS AND EARLY TERTIARY ROCKS FROM FILDES PENINSULA,WEST ANTARCTICA, AND ITS GEOTECTONIC SIGNIFICANCE
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作者 Liu Chun, Zhu Rixiang, Zheng Xiangshen, Liu Xiaohan Jin Zengxin, Feng YuInstitute of Geology, Academia Sinica,Beijing, 100029 Institute of Geophysics, Academia,Sinica,Beijing, 100101 《Chinese Journal of Polar Science》 1992年第1期40-49,共10页
The paleomagnetis m of 109 oriented samples collected from drill cores through 5 rock units of Late Cretaceous and Early Tertiary on Fildes Peninsula were systematically studied-According to the study, the paleomagnet... The paleomagnetis m of 109 oriented samples collected from drill cores through 5 rock units of Late Cretaceous and Early Tertiary on Fildes Peninsula were systematically studied-According to the study, the paleomagnetic pole position of this area is different from the position of Australia during the 55-45 Ma period. This means that when the break - up of the Gondwanaland at 55 - 45 Ma ago, Australia was separated from the Gondwanaland, drifting southward 20°-30°Lat. and rotating 70°-80°westward and then gradually arriving at recent position . The paleolatitudinal data indicate that it is not impossible that the area studied was covered with land glacier at that time. The apparent polar wander path of Antarctica through the geological time are also roughly worked out. 展开更多
关键词 Fildes Peninsula paleomagnetic pole position tectonic displacement apparent polar wander path.
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AN IMPROVED ADAPTIVE THRESHOLD MODULATION METHOD FOR JITTER REDUCTION IN SDH/SONET
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作者 Shi Fuqiang Lin Xiaokang Feng Chongxi (Communication Div., Electron. Eng. Dept., Tsinghua University, Beijing 100084) 《Journal of Electronics(China)》 1999年第3期251-256,共6页
Adaptive threshold modulation is widely adopted in SDH/SONET network for pointer processing and mapping. When the processing rate is very high, the performance of an all digital implementation is limited by the phase ... Adaptive threshold modulation is widely adopted in SDH/SONET network for pointer processing and mapping. When the processing rate is very high, the performance of an all digital implementation is limited by the phase error resolution. Phase error re-sampling technique is adopted here for the all digital implementation of an improved adaptive threshold modulation, which can work in greatly reduced operating speed with high jitter and wander performance. The improved method is adopted in AU-4 and TU-12 pointer processors and the simulated performance is given. 展开更多
关键词 POINTER adjustment Adaptive THRESHOLD MODULATION JITTER wander
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Finite Element Analysis for Groove Wander Prediction of Passenger Car Tires with the Longitudinal Tread Grooves
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作者 Kyoung Moon Jeong Sung Ju Kang +1 位作者 Hyoung Seok Kim Kee Woon Kim 《Engineering(科研)》 2016年第1期11-20,共10页
A finite element modeling technique is employed in this paper to predict the groove wander of longitudinal tread grooved tires. In generally, groove wander is the lateral force acting on a vehicle’s wheel resulting f... A finite element modeling technique is employed in this paper to predict the groove wander of longitudinal tread grooved tires. In generally, groove wander is the lateral force acting on a vehicle’s wheel resulting from the combination of rain grooves. If the lateral force of tire is generated by groove wander, unexpected lateral motion of vehicle will happen and it makes drivers uncomfortable. This paper describes the effect of groove wander according to the shape condition of tire tread groove and highway groove using the finite element analysis based on a static loading or a steady-state rolling assumption. The road groove can be located anywhere relative to the longitudinal tread groove. Therefore, the lateral force of the tire is changing depending on the location of the groove road. The numerical results for groove wander prediction of the longitudinal tread grooved tires are compared with the subjective evaluation. It is found that the waveform for the tire with varying grooved road position has a peak-to-peak lateral force in order to estimate the rating of groove wander. The effect of the road groove width and the pitch length on the peak-to-peak lateral force of tire is discussed. It is found that the prediction of FEA-based groove wander model using finite element analysis will be useful for the reliability design of the tire tread pattern design. 展开更多
关键词 Groove wander TIRE Finite Element Analysis Lateral Force Tread Design
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依循自然的精神自由——庄子“逍遥游”解读 被引量:2
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作者 王焱 《石河子大学学报(哲学社会科学版)》 2009年第3期17-20,共4页
"逍遥"的本义,并非通常所以为的"安闲自得",而是"苦闷"、"无所事事",在庄子那里引申为"无为"。"逍遥游"之"游",亦不等同于西方所谓之"游戏",其本义是... "逍遥"的本义,并非通常所以为的"安闲自得",而是"苦闷"、"无所事事",在庄子那里引申为"无为"。"逍遥游"之"游",亦不等同于西方所谓之"游戏",其本义是"在水中或陆地上活动",在庄子那里引申为"精神空间中的一种行进过程"。"逍遥"与"游"在庄子那里都指向自然与自由。所谓"逍遥游",即依循自然的精神自由。 展开更多
关键词 庄子 逍遥 自然 自由
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