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一类野图的根
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作者 唐秋林 吴美云 《北华大学学报(自然科学版)》 CAS 2007年第4期299-302,共4页
研究了野图·≡·的根,指出其根有无限多个,并给出其根的一般形式.
关键词 野图
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营丘枯木天下无——评李成《寒林平野图》
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作者 叶海晨 《中国人力资源社会保障》 2015年第3期60-,共1页
五代和北宋时期的绘画,以山水画成就最为突出。这一时期的山水画,特别是水墨山水画有了空前发展。绘画选材更加丰富,技法更加精细,出现了讲究笔墨韵味的皴、擦、点、染等技法程式。山水画创作进入高度成熟期。在五代宋初,"营丘李... 五代和北宋时期的绘画,以山水画成就最为突出。这一时期的山水画,特别是水墨山水画有了空前发展。绘画选材更加丰富,技法更加精细,出现了讲究笔墨韵味的皴、擦、点、染等技法程式。山水画创作进入高度成熟期。在五代宋初,"营丘李成、长安关仝、华原范宽",被誉为"三家山水""三家鼎峙,百代标程"。其中。 展开更多
关键词 营丘 三家山水 寒林平野图 山水画创作 水墨山水画 范宽 关仝 五代宋初 《宣和画谱》 画见闻志
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tame根的存在性及其刻画
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作者 苏秀萍 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第6期715-719,共5页
给出了 tame向量、tame根与极小 tame子图的定义 ,以及 tame根的一些刻画 .证明了一个野图有 tame根的充分必要条件是 Q至多有一个 An 型子图且 Q至少有一个极小 tame子图 .
关键词 存在性 tame向量 tame根 极小tame子 代数表示论 野图
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Pinpointing Source of Mekong and Measuring Its Length Through Analysis of Satellite Imagery and Field Investigations 被引量:6
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作者 LIU Shaochuang LU Pingli LIU Donghui JIN Peidong 《Geo-Spatial Information Science》 2007年第1期51-56,共6页
For centuries, explorers and scientists from different countries had made their own conclusions on the source of the Mekong. However, the geographic source of the Mekong is still arguable because of the complexity of ... For centuries, explorers and scientists from different countries had made their own conclusions on the source of the Mekong. However, the geographic source of the Mekong is still arguable because of the complexity of the Mekong source water system, inaccessible environment and the varied technologies used by those explorers and scientists. The satellite remote sensing technology has been used to pinpoint the source of the Mekong, associated with the on-the-spot investigations made by the authors in June 1999 and September 2002. The actual length of the Mekong has also been calculated. 展开更多
关键词 source of Mekong satellite imagery field investigation
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野生野大麦和‘萨尔图’野大麦转录组比较分析
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作者 尹航 吴清莹 +2 位作者 李冰 巩林 崔国文 《分子植物育种》 CAS 北大核心 2022年第7期2118-2125,共8页
野大麦具有耐盐碱、抗旱、耐寒的特点,是中国东北松嫩盐碱草地种植的主要牧草,对改良盐碱草地土壤质量具有重要作用。本研究对野生野大麦和‘萨尔图’野大麦进行了高通量转录组测序,共获得214676个Unigene序列,同时也建立了转录组数据... 野大麦具有耐盐碱、抗旱、耐寒的特点,是中国东北松嫩盐碱草地种植的主要牧草,对改良盐碱草地土壤质量具有重要作用。本研究对野生野大麦和‘萨尔图’野大麦进行了高通量转录组测序,共获得214676个Unigene序列,同时也建立了转录组数据库。转录组数据对比发现,共有的差异表达基因有78505个,‘萨尔图’野大麦中显著上调基因为光系统Ⅱ多肽,显著下调基因为半胱氨酸受体激酶。在KEGG通路富集133条代谢途径,本研究找到了野大麦增产和抗性相关基因,为野大麦及其近缘物种育种提供理论支持,并对东北草地盐碱化的修复及发展畜牧业经济有着重要指导意义。 展开更多
关键词 大麦 ‘萨尔大麦 转录组 差异基因 功能注释
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由《秀野轩图》看朱德润晚年画风的转变
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作者 张怡 《爱尚美术》 2018年第5期46-55,共10页
《秀野轩图》是元代画家朱德润为好友周景安所作,为其晚期画风的代表作品。此卷技法受董、巨画法影响较大,多用披麻皴,以半干墨笔皴擦,苍润厚重,与早期《浑沦图》中呈现出的李、郭一派画法区别甚大。朱德润(1294年-1365年),字泽民,平江... 《秀野轩图》是元代画家朱德润为好友周景安所作,为其晚期画风的代表作品。此卷技法受董、巨画法影响较大,多用披麻皴,以半干墨笔皴擦,苍润厚重,与早期《浑沦图》中呈现出的李、郭一派画法区别甚大。朱德润(1294年-1365年),字泽民,平江(今江苏苏州)人,元代著名的画家,吴兴画派代表人物之一。 展开更多
关键词 朱德润
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Integrating Remote Sensing and Field Survey to Map Shallow Water Benthic Habitat for the Kingdom of Bahrain
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作者 Sabah Aljenaid Eman Ghoneim +5 位作者 Mohammed Abido Khalil AlWedhai Ghadeer Khadim Saeed Mansoor Wisam EL-Deen Mohd Nadir Abd Hameed 《Journal of Environmental Science and Engineering(B)》 2017年第4期176-200,共25页
Identification and classification, as well as mapping of marine habitats, are of primary importance to plan management activities, especially in disturbed ecosystems like the ones in the marine areas of Bahrain. Remot... Identification and classification, as well as mapping of marine habitats, are of primary importance to plan management activities, especially in disturbed ecosystems like the ones in the marine areas of Bahrain. Remotely sensed Landsat-8 imagery coupled with field survey was used to identify, classify and map the benthic habitats in Bahrain marine area. The used geospatial techniques include advanced image processing procedures, which comprise of radiometric and atmospheric corrections, sun glint removal, water depth correction and image classification. Extensive ground-truthing analyses through in-situ field surveys by a team of scuba divers were conducted in October 2014 and June 2015 to inform and refine the classifications. The variables collected from this survey included physical and chemical characteristics of the water, habitat type, substrata, fauna and flora. A total of 176 field points were collected and utilized to perform an accurate assessment of the image classification. Initial habitat classification resulted in 20 habitat categories. However, due to the inability of the Landsat-8 sensors to accurately discriminate that level of classification, categories were merged into seven classes. The derived map shows that the benthic marine habitats of Bahrain consist of deep water (2,523 km2), rock (1,738 km2), sand (1,191 km2), deep water/sand (1,006 km2), algae (922 km2), seagrass (591 km2) and corals (275.50 km2). Although limited by the spatial and spectral resolutions of Landsat 8, the used methods produced a suitable map of the benthic habitats within the marine area of Bahrain with an overall accuracy of 84.1%. The use of very high spatial resolution satellite imagery will most likely increase such accuracy significantly. 展开更多
关键词 Landsat 8 MARINE water column correction scuba diving GIS (Geographic Information System)
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Vision-based behavior prediction of ball carrier in basketball matches 被引量:2
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作者 夏利民 王千 吴联世 《Journal of Central South University》 SCIE EI CAS 2012年第8期2142-2151,共10页
A new vision-based approach was presented for predicting the behavior of the ball carrier—shooting, passing and dribbling in basketball matches. It was proposed to recognize the ball carrier’s head pose by classifyi... A new vision-based approach was presented for predicting the behavior of the ball carrier—shooting, passing and dribbling in basketball matches. It was proposed to recognize the ball carrier’s head pose by classifying its yaw angle to determine his vision range and the court situation of the sportsman within his vision range can be further learned. In basketball match videos characterized by cluttered background, fast motion of the sportsmen and low resolution of their head images, and the covariance descriptor, were adopted to fuse multiple visual features of the head region, which can be seen as a point on the Riemannian manifold and then mapped to the tangent space. Then, the classification of head yaw angle was directly completed in this space through the trained multiclass LogitBoost. In order to describe the court situation of all sportsmen within the ball carrier’s vision range, artificial potential field (APF)-based information was introduced. Finally, the behavior of the ball carrier—shooting, passing and dribbling, was predicted using radial basis function (RBF) neural network as the classifier. Experimental results show that the average prediction accuracy of the proposed method can reach 80% on the video recorded in basketball matches, which validates its effectiveness. 展开更多
关键词 covariance descriptor tangent space LogitBoost artificial potential field radial basis function neural network
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李成:文气十足 秀润不凡
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作者 沈颖 《山东艺术》 2019年第4期50-57,共8页
一、李成的山东渊源齐鲁大地历史上孕育过许多的名贤学者,李成是山东土生土长的画家。李成,字咸熙,生于后梁末帝贞明五年(919),死于宋太祖乾德五年(967),祖籍长安(今陕西西安)。五代时期战乱纷扰,因避乱,其祖父携全家从苏州迁至营丘(今... 一、李成的山东渊源齐鲁大地历史上孕育过许多的名贤学者,李成是山东土生土长的画家。李成,字咸熙,生于后梁末帝贞明五年(919),死于宋太祖乾德五年(967),祖籍长安(今陕西西安)。五代时期战乱纷扰,因避乱,其祖父携全家从苏州迁至营丘(今山东临淄,一说青州),因此被人们称为'李营丘'。齐鲁文化的雄厚底蕴,为李成的成长和发展提供了良好的基础。 展开更多
关键词 黄公望 寒林平野图 山水画
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Multifocal electroretinograms in the early stages of diabetic retinopathy 被引量:1
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作者 余敏忠 张欣 +4 位作者 钟兴武 于强 江福钿 马娟妹 吴德正 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第4期563-566,共4页
OBJECTIVE: To investigate the characteristics of multifocal electroretinograms (mf-ERG) of different phases in diabetic retinopathy (DR) and its clinical significance. METHODS: Multifocal electroretinograms in patient... OBJECTIVE: To investigate the characteristics of multifocal electroretinograms (mf-ERG) of different phases in diabetic retinopathy (DR) and its clinical significance. METHODS: Multifocal electroretinograms in patients with DR (I - II stage) were tested with VERIS IV system. RESULTS: In I - II stage, the absolute values of N1, P1 and N2 response densities, and the N1-P1 and P1-N2 response densities were attenuated is a field of about 45 degrees in diameter. CONCLUSION: As a new objective and quantitative examination for spatial visual function, multifocal electroretinograms may be valuable in the diagnosis of diabetic retinopathy. 展开更多
关键词 Aged Diabetic Retinopathy ELECTRORETINOGRAPHY FEMALE Humans MALE Middle Aged RETINA Time Factors
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彪炳千古的山水名作——五代北宋山水名家及作品浅析 被引量:1
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作者 薄松年 《荣宝斋》 2004年第3期5-29,共25页
以自然风光为题材的绘画在古今中外的画坛上曾产生过不少优秀之作,而中国山水画尤以历史悠久成就卓越和风格独特而享誉于世界。在西欧风景画尚未萌发之时,中国山水画就早已进入高度成熟阶段,艺术上放出耀眼的光辉。
关键词 山水画家 巨然 荆浩 董源 李成 台北故宫博物院 寒林平野图 郭熙
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Multifocal electroretinograms in the early stages of diabetic retinopathy
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作者 余敏忠 张欣 +4 位作者 钟兴武 于强 江福钿 马娟妹 吴德正 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第4期83-86,152,共5页
To investigate the characteristics of multifocal electroretinograms (mf ERG) o f different phases in diabetic retinopathy (DR) and its clinical significance Methods Multifocal electroretinograms in patients with D... To investigate the characteristics of multifocal electroretinograms (mf ERG) o f different phases in diabetic retinopathy (DR) and its clinical significance Methods Multifocal electroretinograms in patients with DR (Ⅰ-Ⅱ stage) were tested with VERIS Ⅳ system Results In Ⅰ-Ⅱ stage, the absolute values of N1, P1 and N2 response densities, and the N1 P1 and P1 N2 response densities were attenuated is a field of about 45 deg rees in diameter Conclusion As a new ABSTRACT and quantitative examination for spatial visual function, mul tifocal electroretinograms may be valuable in the diagnosis of diabetic retinopa thy 展开更多
关键词 diabetic retinopathy · multifocal electrore tinogram · visual field · eccentricity
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Pathological morphology alteration of the splanchnic vascular wall in portal hypertensive patients
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作者 杨镇 张黎 +1 位作者 李大鹏 裘法祖 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第4期79-82,152,共5页
To investigate the pathological morphology alteration of the splanchnic vascular wall in portal hypertensive patients Methods Splenic arteries, veins and gastric coronary veins from portal hypertensive pati ents (n... To investigate the pathological morphology alteration of the splanchnic vascular wall in portal hypertensive patients Methods Splenic arteries, veins and gastric coronary veins from portal hypertensive pati ents (n=50) were removed during esophagogastric devascularization with splenecto my and were observed under optic and electron microscopes The expression of iN OS in the splenic artery wall was analysed with immunohistochemistry Results The internal elastic membrane and medial elastic fibers of the splenic artery wa ll were broken and degenerated Atrophy, apoptosis and phenotypic changes were seen in smooth muscle cells of splenic arteries Positive staining for iNOS was seen in the cytoplasm of smooth muscle cells and iNOS activity was elevated com pared with the non cirrhotic patients ( P 【0 01) In the splenic and gastri c coronary veins of cirrhotic patients, we found proliferative intima, extensive thrombi adhering to the venous wall, mimicked arteriosclerosis plaques accompan ied with hypertrophy of smooth muscle cells, and thickened muscle fibers of vein s with increase in extracelluar matrix Conclusion Portal hypertension may be complicated by splanchnic arterial and venous vasculo pathy There may be an interactive relationship among portal hypertension, spla nchnic hyperdynamic disturbances and splanchnic vasculopathy in the pathogenesis of portal hypertension 展开更多
关键词 portal vein hypertension · vasculopathy · pathology
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Activity of the Lenglongling fault system and seismotectonics of the 2016 MS6.4 Menyuan earthquake 被引量:20
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作者 GUO Peng HAN ZhuJun +3 位作者 AN YanFen JIANG WenLiang MAO ZeBin FENG Wei 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第5期929-942,共14页
The MS6.4 Menyuan earthquake occurred on the northern side of the Lenglongling fault(LLLF) in the mid-western of the Qilian-Haiyuan fault zone on January 21, 2016. The earthquake epicenter was distant from the Minle-D... The MS6.4 Menyuan earthquake occurred on the northern side of the Lenglongling fault(LLLF) in the mid-western of the Qilian-Haiyuan fault zone on January 21, 2016. The earthquake epicenter was distant from the Minle-Damaying and Huangcheng-Shuangta faults, eastern of the Northern Qilian Shan fault zone. A near northwest-striking rupture plane intersects the two faults at a certain angle. The focal mechanism solution shows that this was a thrust-type earthquake, slightly different from the strike-slip movement with a thrust component of the LLLF. Field geological mapping, tectonic geomorphology analysis, trench excavation and 14 C dating reveal that(1) the LLLF has been obviously active since the Holocene, and may behave with characteristic slip behavior and produce M_W7.3–7.5 earthquakes;(2) the LLLF appears as a flower structure in terms of structure style, and dips NNE at a steep angle; and(3) the most recent earthquake event occurred after 1815–1065 a BP. An associated fault, the Northern Lenglongling fault(NLLLF), is located at the northwestern end of the LLLF. Consequently, the NLLLF was continually subject to tectonic pushing effects from the left-lateral shear at the end of the LLLF, and, accordingly, it bent and rotated outward tectonically.Subsequently, the fault deviated from the dominant rupture azimuth and activity weakened. In the late Quaternary, it behaved as a thrust fault with no obvious deformation at the surface. This is indicated by the arc shape, with a micro-protrusion northeastward,and no geologic or geomorphic signs of surface rupturing since the late Quaternary. However, such faults could still rupture at depth, producing moderate-strong earthquakes. The geometric and kinematic properties of the NLLLF are in good agreement with the occurrence and kinematic properties of nodal plane 2, and with the distribution characteristics of the aftershocks and seismic intensity. Therefore, the NLLLF is a more suitable seismogenic structure for the MS 6.4 Menyuan earthquake. In addition, the thrust movement of the NLLLF accommodates subsequent movement of the LLLF. During the historical evolution of the NLLLF,the LLLF and the NLLLF have affected the local topography through tectonic uplift. 展开更多
关键词 MS6 4 Mengyuan earthquake Seismogenic structure Tectonic environment Lenglongling fault Northern Lenglongling fault
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Take only pictures, leave only...fear? The effects of photography on the West Indian anole Anolis cristatellus 被引量:2
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作者 Brian HUANG Katie LUBARSKY Tiffany TENG Daniel T. BLUMSTEIN 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第1期77-82,共6页
Ecotourism encourages an environmentally friendly exploration of the world's natural habitats. Tourists often engage in wildlife photography, an activity that is generally not considered disturbing to animals. We inv... Ecotourism encourages an environmentally friendly exploration of the world's natural habitats. Tourists often engage in wildlife photography, an activity that is generally not considered disturbing to animals. We investigated the effects of cam- era-related stimuli to determine whether shutter noise and/or flash affected the immediate behavior of female crested anoles Ano- lis cristaellus. Anoles decreased their display rate following stimuli that included shutter noises, but did not change their behavior in response to flash or silence treatments. To determine the relative importance of this response, we observed anole behavior fol- lowing playbacks of calls from kestrels Falco sparverius, a predator, and bananaquits Coereba flaveola, a non-predator. Anoles decreased display rates following kestrel calls when compared to their response to bananaquit calls. Furthermore, anoles spent a greater proportion of time displaying following bananaquit calls compared to both kestrel calls and silence. The magnitude of response to shutter noises was about the same as that to predator calls. This demonstrates that photography may not be as benign as commonly believed, and we should consider whether restrictions on camera noises should be implemented to reduce ani- mal disturbance 展开更多
关键词 Antipredator Behavior ECOTOURISM PHOTOGRAPHY Anoles Multimodal Risk Assessment
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