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“Grafting from”法制备高载量大孔弱阳离子交换层析介质
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作者 郭旺 姜泽平 +6 位作者 马磊 乔娟 莫文清 靳海波 何广湘 黄永东 张荣月 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第3期64-72,共9页
针对大孔聚合物层析介质孔径大、比表面积低而导致的蛋白结合容量低的问题,采用“graftingfrom”策略,以大孔聚丙烯酸酯微球为基质,通过氧化还原引发甲基丙烯酸在微球表面接枝聚合,制备了高载量弱阳离子交换层析介质.研究了单体浓度、... 针对大孔聚合物层析介质孔径大、比表面积低而导致的蛋白结合容量低的问题,采用“graftingfrom”策略,以大孔聚丙烯酸酯微球为基质,通过氧化还原引发甲基丙烯酸在微球表面接枝聚合,制备了高载量弱阳离子交换层析介质.研究了单体浓度、过硫酸钾浓度及反应温度等因素对蛋白结合容量的影响.所得介质的蛋白静态结合容量和动态结合容量分别达到252.21和157.25mg/mL;同时发现具有一定离子交换容量的该类介质能够在0.2 mol/L NaCl缓冲液中保持100 mg/mL的蛋白结合容量.将该层析介质用于鸡卵清中溶菌酶的纯化,获得了较高的纯化效率. 展开更多
关键词 弱阳离子交换层析介质 大孔聚合物 蛋白结合容量 Grafting from 分离纯化
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Origin of Sexy Prime Numbers, Origin of Cousin Prime Numbers, Equations from Supposedly Prime Numbers, Origin of the Mersenne Number, Origin of the Fermat Number
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作者 Mady Ndiaye 《Advances in Pure Mathematics》 2024年第5期321-332,共12页
We have found through calculations that the differences between the closest supposed prime numbers other than 2 and 3 defined in the articles are: 2;4: and 6. For those whose difference is equal to 6, we showed their ... We have found through calculations that the differences between the closest supposed prime numbers other than 2 and 3 defined in the articles are: 2;4: and 6. For those whose difference is equal to 6, we showed their origin then we classified them into two categories according to their classes, we showed in which context two prime numbers which differ from 6 are called sexy and in what context they are said real sexy prime. For those whose difference is equal to 4, we showed their origin then we showed that two prime numbers which differ from 4, that is to say two cousin prime numbers, are successive. We made an observation on the supposed prime numbers then we established two pairs of equations from this observation and deduced the origin of the Mersenne number and that of the Fermat number. 展开更多
关键词 Cousin Prime Numbers Sexy Prime Numbers Real Sexy Prime Numbers Equations from Supposed Prime Numbers Mersenne Number Fermat Number Supposed Prime Numbers Prime Numbers
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语义构建中的认知识解因素——以die of X和die from X为个案
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作者 戴志军 《黑河学院学报》 2023年第3期123-125,共3页
语义构建离不开认知识解因素。die of和die from可以与同样的表达式搭配,即die of X和die from X。就规约意义而言,die of X通常表达客观的、直接的原因,而die from X通常表达客观的、间接的原因。但在die of X和die from X语义构建过程... 语义构建离不开认知识解因素。die of和die from可以与同样的表达式搭配,即die of X和die from X。就规约意义而言,die of X通常表达客观的、直接的原因,而die from X通常表达客观的、间接的原因。但在die of X和die from X语义构建过程中,通过认知识解,客观的、直接的原因会被识解为主观的、间接原因,客观的、间接的原因会被构建为主观的、直接的原因。 展开更多
关键词 die of X die from X 语义构建 认知识解
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A Seismic Facies Analysis to Determine the Relative Age and History of the Al Idrissi Mud Volcano from Offshore Larache Located in the NW Moroccan Atlantic Margin
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作者 Asher Hategekamungu Nadia Mhammdi +1 位作者 Mohamed Amine Manar Asmae Bernachid 《Open Journal of Geology》 CAS 2023年第3期203-220,共18页
Formed on top of the Gulf of Cadiz, the Al Idrissi mud volcano is the shallowest and largest mud volcano in the El Arraiche mud volcano field of the northwestern Moroccan margin. The development and morphology of mud ... Formed on top of the Gulf of Cadiz, the Al Idrissi mud volcano is the shallowest and largest mud volcano in the El Arraiche mud volcano field of the northwestern Moroccan margin. The development and morphology of mud volcanoes from the El Arraiche mud volcanoes group have been studied at a large scale. However, the time interval related to their formation period still needs to be better understood. In this regard, we interpreted and analyzed the seismic facies from the 2D reflection data of the GEOMARGEN-1 campaign, which took place in 2011. The aim was to identify the seismic sequences and draw the Al Idrissi mud volcano system to determine the formation period of the Al Idriss mud volcano. And as a result, the Al Idrissi mud volcano system is made of both buried and superficial bicone and was identified along with the Upper Tortonian to Messinian-Upper Pliocene facies. As the initial mud volcano extrusive edifice, the buried bicone was formed in the Late-Messinian to Early-Pliocene period. However, the superficial bicone, as the final extrusive edifice, was included in the Late Pliocene. In this case, the timing interval between the buried and superficial bicone is equivalent to the Late-Messinian to Upper-Pliocene period. Therefore, the latter corresponds to the Al Idrissi mud volcano formation period. 展开更多
关键词 Northwestern Moroccan Margin Al Idrissi Mud Volcano 2D Reflection Data from the GEOMARGEN-1 Campaign Seismic Signatures Analysis Formation Period
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Exciting News from Indentations onto Silicon, Copper, and Tungsten
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作者 Gerd Kaupp 《Journal of Applied Mathematics and Physics》 2023年第12期4042-4078,共37页
Indentations onto crystalline silicon and copper with various indenter geometries, loading forces at room temperature belong to the widest interests in the field, because of the physical detection of structural phase ... Indentations onto crystalline silicon and copper with various indenter geometries, loading forces at room temperature belong to the widest interests in the field, because of the physical detection of structural phase transitions. By using the mathematically deduced F<sub>N</sub>h<sup>3/2 </sup>relation for conical and pyramidal indentations we have a toolbox for deciding between faked and experimental loading curves. Four printed silicon indentation loading curves (labelled with 292 K, 260 K, 240 K and 210 K) proved to be faked and not experimental. This is problematic for the AI (artificial intelligence) that will probably not be able to sort faked data out by itself but must be told to do so. High risks arise, when published faked indentation reports remain unidentified and unreported for the mechanics engineers by reading, or via AI. For example, when AI recommends a faked quality such as “no phase changes” of a technical material that is therefore used, it might break down due to an actually present low force, low transition energy phase-change. This paper thus installed a tool box for the distinction of experimental and faked loading curves of indentations. We found experimental and faked loading curves of the same research group with overall 14 authoring co-workers in three publications where valid and faked ones were next to each other and I can thus only report on the experimental ones. The comparison of Si and Cu with W at 20-fold higher physical hardness shows its enormous influence to the energies of phase transition and of their transition energies. Thus, the commonly preferred ISO14577-ASTM hardness values HISO (these violate the energy law and are simulated!) leads to almost blind characterization and use of mechanically stressed technical materials (e.g. airplanes, windmills, bridges, etc). The reasons are carefully detected and reported to disprove that the coincidence or very close coincidence of all of the published loading curves from 150 K to 298 K are constructed but not experimental. A tool-box for distinction of experimental from faked indentation loading curves (simulations must be indicated) is established in view of protecting the AI from faked data, which it might not be able by itself to sort them out, so that technical materials with wrongly attributed mechanical properties might lead to catastrophic accidents such as all of us know of. There is also the risk that false theories might lead to discourage the design of important research projects or for not getting them granted. This might for example hamper or ill-fame new low temperature indentation projects. The various hints for identifying faked claims are thus presented in great detail. The low-temperature instrumental indentations onto silicon have been faked in two consecutive publications and their reporting in the third one, so that these are not available for the calculation of activation energies. Conversely, the same research group published an indentation loading curve of copper as taken at 150 K that could be tested for its validity with the therefore created tools of validity tests. The physical algebraic calculations provided the epochal detection of two highly exothermic phase transitions of copper that created two polymorphs with negative standard energy content. This is world-wide the second case and the first one far above the 77 K of liquid nitrogen. Its existence poses completely new thoughts for physics chemistry and perhaps techniques but all of them are open and unprepared for our comprehension. The first chemical reactions might be in-situ photolysis and the phase transitions can be calculated from experimental curves. But several further reported low temperature indentation loading curves of silicon were tested for their experimental reality. And the results are compared to new analyses with genuine room temperature results. A lot is to be learned from the differences at room and low temperature. 展开更多
关键词 Phase-Transition-Onset and -Energy Indentation of Silicone COPPER Copper Nanoparticles Tungsten with Polymorphs Low-Temperature Indentations Detection of Faked Loading Curves Protection of AI from False Advices Risk of Catastrophic Crashes Physical Hardness Exothermic Copper-Transitions Algebraic Calculations Negative-Standard-Energy Polymorphs
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Antibacterial Effect of Extracts from Allium mongolicum Regel 被引量:9
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作者 李亚蕾 罗瑞明 《Agricultural Science & Technology》 CAS 2008年第4期123-126,共4页
[Objective] Study on antibacterial activity and stability of the ethanol extracts from Allium mongolicum Regel.[Method] Taking Allium mongolicum Regel.(AMR)as experimental material,the antibacterial and stability test... [Objective] Study on antibacterial activity and stability of the ethanol extracts from Allium mongolicum Regel.[Method] Taking Allium mongolicum Regel.(AMR)as experimental material,the antibacterial and stability test,antibacterial capacity and antibacterial activity substance stability of extracts were studied.[Result] Size order of antibacterial effect of extracts on these 5 strains tended to be:Saccharomyces cerevisiae > Penicillium sp.> Aspergillusniger> Staphylococcusaureus> Escherichia coli;under neutral or slight alkaline conditions,optimum antibacterial effect presented best;and UV light irradiation basically had no influence on tested strains.[Conclusion] Antibacterial effect of ethanol extract shows great difference among these strains,and antibacterial activity substance is of good heat and UV light stability. 展开更多
关键词 EXTRACTS from ALLIUM mongolicum Regel ANTIBACTERIAL EFFECT STABILITY
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基于shape from silhouette方法的虚拟人体构造 被引量:4
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作者 沈军行 孙守迁 +1 位作者 黄琦 潘云鹤 《中国图象图形学报(A辑)》 CSCD 北大核心 2002年第10期1089-1093,共5页
逼真的人体三维模型 (虚拟人体 )在产品设计、计算机动画、虚拟现实等领域都有着广泛的需求 .为此 ,提出了一种基于 shape from silhouette的人体三维模型构造方法 .该方法所需要的器材只是一个普通的数码相机 ,通过从不同角度对人体进... 逼真的人体三维模型 (虚拟人体 )在产品设计、计算机动画、虚拟现实等领域都有着广泛的需求 .为此 ,提出了一种基于 shape from silhouette的人体三维模型构造方法 .该方法所需要的器材只是一个普通的数码相机 ,通过从不同角度对人体进行拍摄 ,然后经过摄像机定标、体积生成、表面重建、纹理映射后就可重建出逼真的人体三维模型 .实验结果表明 ,此方法精度较高 ,整个过程简单快捷 ,是一种非常实用的方法 . 展开更多
关键词 虚拟人体 三维重建 ShapefromSilhouette 表面重建 纹理映射 计算机动画 人体三维模型 产品设计 虚拟现实
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基于Shape-from-Shading的月球表面三维形状恢复算法研究 被引量:2
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作者 杨磊 韩九强 王国珲 《宇航学报》 EI CAS CSCD 北大核心 2008年第6期1995-2000,共6页
提出了一种基于Shape-from-Shading的月球表面三维形状恢复算法。首先分析了在太阳光照射下月球表面成像模型,建立了使用Lommel-Seeliger反射模型描述的反射图方程。然后用有限差分近似微分运算,将反射图方程所示的一阶变系数线性偏微... 提出了一种基于Shape-from-Shading的月球表面三维形状恢复算法。首先分析了在太阳光照射下月球表面成像模型,建立了使用Lommel-Seeliger反射模型描述的反射图方程。然后用有限差分近似微分运算,将反射图方程所示的一阶变系数线性偏微分方程进行离散化处理,得到关于表面高度函数的代数方程。进而采用超松弛迭代法进行求解,获得月球表面三维高度函数值。最后使用合成图像和实际月球图像进行三维形状恢复仿真实验。实验结果表明提出的算法可以有效地恢复月球表面三维形状。 展开更多
关键词 月球表面 三维形状恢复 Shape-from—Shading Lommel—Seeliger反射模型 有限差分
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基于Shape from Shading的医学图像三维重建 被引量:4
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作者 王瑞胡 《计算机工程与应用》 CSCD 北大核心 2008年第6期222-224,共3页
通过对由医疗成像设备获取的二维灰度图像进行形状重建,得到的三维立体原型能帮助医学诊断人员确诊病情。介绍了Shape from Shading的实现原理和扫描电镜成像系统的简单构成,提出了一种基于线性逼近的用于解决SEM反射映射函数的实现方法... 通过对由医疗成像设备获取的二维灰度图像进行形状重建,得到的三维立体原型能帮助医学诊断人员确诊病情。介绍了Shape from Shading的实现原理和扫描电镜成像系统的简单构成,提出了一种基于线性逼近的用于解决SEM反射映射函数的实现方法,并将之应用于红血细胞的三维图像重构,得到的细胞图形非常接近其真实形状。 展开更多
关键词 SHAPE from SHADING 扫描电镜 三维重建 红血细胞图像
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英语介词from的语义、修辞功能 被引量:2
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作者 陈绍恋 《辽宁工程技术大学学报(社会科学版)》 2007年第3期308-310,共3页
from是英语中最重要的介词之一,它常与其他的词搭配成许多习语性短语,具有丰富的语义功能。针对很多外语学习者很难自然地道、符合习惯地运用它这一现状,将从语义的角度对其加以全面的梳理。而且,它还具有丰富的修辞功能,充分挖掘这一功... from是英语中最重要的介词之一,它常与其他的词搭配成许多习语性短语,具有丰富的语义功能。针对很多外语学习者很难自然地道、符合习惯地运用它这一现状,将从语义的角度对其加以全面的梳理。而且,它还具有丰富的修辞功能,充分挖掘这一功能,有助于提高人们的语言表达效果,加强的语言修养。 展开更多
关键词 介词from 语义功能 修辞功能
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认知视角下《麦克白》中介词FROM的空间隐喻研究 被引量:3
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作者 谢世坚 陈缘缘 《黑龙江教育学院学报》 2019年第5期122-126,共5页
《麦克白》中介词from的空间隐喻用法丰富。基于此,在认知语言学意象图式的视角下探讨《麦克白》中介词from的基本空间语义用法和空间隐喻用法,发现介词from具有多层次的空间隐喻意义。研究《麦克白》中介词from的空间隐喻,可以为人们... 《麦克白》中介词from的空间隐喻用法丰富。基于此,在认知语言学意象图式的视角下探讨《麦克白》中介词from的基本空间语义用法和空间隐喻用法,发现介词from具有多层次的空间隐喻意义。研究《麦克白》中介词from的空间隐喻,可以为人们提供一个有利于理解和欣赏莎士比亚戏剧语言的新视角。 展开更多
关键词 介词from 空间隐喻 意象图式 《麦克白》
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流向图回溯法及传输网络From-To解算方法和技术研究
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作者 冯治东 张培元 《计算机系统应用》 2018年第6期225-230,共6页
针对传输网络中流体"从哪里来,到哪里去"的确定问题,基于图回溯法,提出了一种基于流向图的传输网络From-To解算方法.根据传输网络中的驱动点、管道、闸阀和出口各属性状态,将整个网络转化为初始流向图拓扑结构,根据图回溯原理... 针对传输网络中流体"从哪里来,到哪里去"的确定问题,基于图回溯法,提出了一种基于流向图的传输网络From-To解算方法.根据传输网络中的驱动点、管道、闸阀和出口各属性状态,将整个网络转化为初始流向图拓扑结构,根据图回溯原理,逐步累积计算管道中流体的来源和去向,直到全部管道回溯结束,得出最终流向图.在此基础上,研发了基于Observer设计模式的"From-To解算"通用组件接口,并被应用于某大型煤矿的复杂排水管网的计算机仿真平台中,应用效果较好. 展开更多
关键词 传输网络 流向图 from-To解算 回溯法 矿井排水
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浅析Select…From…Where命令中的“前点”与“后点”
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作者 白学清 李富星 郭协潮 《延安大学学报(自然科学版)》 2005年第3期20-23,共4页
为了深刻理解SQL语言中的查询命令,笔者根据教学体会,提出蕴含于该命令中的“前点”、“中点”和“后点”的概念,并结合一个实例详细地分析他们相互之间的作用和联系。
关键词 Select…from…Where 前点 后点
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英语的范围构式“from A to B”研究
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作者 倪涛 《通化师范学院学报》 2015年第5期34-37,共4页
以构式理论为基础"from A to B"的其结构变化、句法功能、表义类型以及范围特征的考察发现:"from A to B"是英语中一种表达起讫范围的习语性构式,主要表示空间范围,其认知机制是"部分-整体"的转喻。同时... 以构式理论为基础"from A to B"的其结构变化、句法功能、表义类型以及范围特征的考察发现:"from A to B"是英语中一种表达起讫范围的习语性构式,主要表示空间范围,其认知机制是"部分-整体"的转喻。同时,在语言使用中,"from A to B"也常表示时间、数量、事物和事件等范围,这些范围类型都来自于其空间概念的隐喻投射。 展开更多
关键词 范围构式 from A to B 转喻 隐喻
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An Existentialist Study of Notes from Underground
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作者 刘晓华 《海外英语》 2012年第1X期213-214,共2页
This article intends to analyze the protagnist the underground man in Notes from Underground from a new angle-existentialism.Through the analysis it displays the actual situation of the individual existence in modern ... This article intends to analyze the protagnist the underground man in Notes from Underground from a new angle-existentialism.Through the analysis it displays the actual situation of the individual existence in modern society and the tension between the individual existence and the social existence. 展开更多
关键词 NOTES from UNDERGROUND the UNDERGROUND MAN existen
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若即若离,美之大成——“A Bird Came down from the Walk”的美感分析
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作者 王欣欣 《佳木斯职业学院学报》 2018年第10期82-83,共2页
作为现代主义文学先驱的艾米丽·狄金森,一生传世的作品有一千七百多首。她的大量作品是歌颂自然之美的。其中一首动人的诗作:"A Bird Came down from the Walk"体现了她深谙自然界蕴含的灵动之美。本文以朱光潜的文艺心... 作为现代主义文学先驱的艾米丽·狄金森,一生传世的作品有一千七百多首。她的大量作品是歌颂自然之美的。其中一首动人的诗作:"A Bird Came down from the Walk"体现了她深谙自然界蕴含的灵动之美。本文以朱光潜的文艺心理学中的审美距离理论为依据。通过两个角度分析了这首诗作:一是审美者与审美对象要保持一定的心理距离。二是审美者与审美对象要达到物我同一的境界。结论:在文学作品创作,尤其是诗歌创作中,若即若离是创造美感的最佳距离。 展开更多
关键词 “A BIRD Came DOWN from the Walk” 心理距离 物我同一 若即若离
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线性和环型Consecutive-k-out-of-r-from-n:F系统可靠性的精确解 被引量:2
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作者 韩清 《数理统计与管理》 CSSCI 北大核心 2002年第5期26-31,25,共7页
本文利用马氏链嵌入法给出了工程上被称为Consecutive k out of r from n :F系统的可靠性精确解。这种方法适用于较复杂的系统可靠性计算 ,且易于在计算机上实现。
关键词 Consecutive-k-out-of-r-from-n:F系统 可靠性 精确解 马氏链嵌入法 Scan统计量
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介词From的意象图式解析 被引量:2
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作者 刘翠翠 王洪刚 《西昌学院学报(社会科学版)》 2019年第1期93-96,共4页
介词是中国语言学习者在学习外语过程中不可避免的部分,传统语法和认知语法都对介词给出各自解释。主张运用认知语言学中的意象图式对介词From作出解释,通过运用意象图式对介词From的分析,深入了解其基本意义及延伸意义,并以期揭示介词... 介词是中国语言学习者在学习外语过程中不可避免的部分,传统语法和认知语法都对介词给出各自解释。主张运用认知语言学中的意象图式对介词From作出解释,通过运用意象图式对介词From的分析,深入了解其基本意义及延伸意义,并以期揭示介词研究的新途径,为积极促进介词的有效学习提供可能性。 展开更多
关键词 认知语言学 意象图式 介词from
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基于Depth from Focus的图像三维重建 被引量:7
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作者 王金岩 史文华 敬忠良 《南京航空航天大学学报》 EI CAS CSCD 北大核心 2007年第2期181-186,共6页
应用改进Laplacian聚焦算子实现序列图像的融合显示,用高斯插值算法得到图像三维重建中的高度图,并设计一种轮廓线算法对高度索引图进行了三维重建;成功地应用于摄像机拍摄序列图像的三维重建,弥补了摄像机物镜焦深范围有限不能采样清... 应用改进Laplacian聚焦算子实现序列图像的融合显示,用高斯插值算法得到图像三维重建中的高度图,并设计一种轮廓线算法对高度索引图进行了三维重建;成功地应用于摄像机拍摄序列图像的三维重建,弥补了摄像机物镜焦深范围有限不能采样清晰大幅图像的不足。理论和实验结果证明,用该方法生成的二维融合图像和三维显示图像,恢复出比较精确的物体表面深度信息,提高了图像的清晰度。 展开更多
关键词 图像融合 图像三维重建 聚焦深度 序列图像
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介词from的意象图式及其认知域投射 被引量:6
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作者 朱晓静 《四川教育学院学报》 2010年第8期82-84,共3页
通过运用认知工具"意象图式"对介词from进行认知分析,探究了介词from的中心意象图式与其延伸图式之间的关系,发现介词from可以表示实体间朝向并追溯到的动态关系,也可以表示静态的空间位置关系。在此基础上探讨了介词from以... 通过运用认知工具"意象图式"对介词from进行认知分析,探究了介词from的中心意象图式与其延伸图式之间的关系,发现介词from可以表示实体间朝向并追溯到的动态关系,也可以表示静态的空间位置关系。在此基础上探讨了介词from以空间投射为基础的五种不同的认知域投射,认为意象图式是一种有效的分析空间方位词义的认知工具。 展开更多
关键词 介词from 意象图式 认知域
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