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Intelligent diagnosis of retinal vein occlusion based on color fundus photographs
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作者 Yu-Ke Ji Rong-Rong Hua +3 位作者 Sha Liu Cui-Juan Xie Shao-Chong Zhang Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期1-6,共6页
AIM:To develop an artificial intelligence(AI)diagnosis model based on deep learning(DL)algorithm to diagnose different types of retinal vein occlusion(RVO)by recognizing color fundus photographs(CFPs).METHODS:Totally ... AIM:To develop an artificial intelligence(AI)diagnosis model based on deep learning(DL)algorithm to diagnose different types of retinal vein occlusion(RVO)by recognizing color fundus photographs(CFPs).METHODS:Totally 914 CFPs of healthy people and patients with RVO were collected as experimental data sets,and used to train,verify and test the diagnostic model of RVO.All the images were divided into four categories[normal,central retinal vein occlusion(CRVO),branch retinal vein occlusion(BRVO),and macular retinal vein occlusion(MRVO)]by three fundus disease experts.Swin Transformer was used to build the RVO diagnosis model,and different types of RVO diagnosis experiments were conducted.The model’s performance was compared to that of the experts.RESULTS:The accuracy of the model in the diagnosis of normal,CRVO,BRVO,and MRVO reached 1.000,0.978,0.957,and 0.978;the specificity reached 1.000,0.986,0.982,and 0.976;the sensitivity reached 1.000,0.955,0.917,and 1.000;the F1-Sore reached 1.000,0.9550.943,and 0.887 respectively.In addition,the area under curve of normal,CRVO,BRVO,and MRVO diagnosed by the diagnostic model were 1.000,0.900,0.959 and 0.970,respectively.The diagnostic results were highly consistent with those of fundus disease experts,and the diagnostic performance was superior.CONCLUSION:The diagnostic model developed in this study can well diagnose different types of RVO,effectively relieve the work pressure of clinicians,and provide help for the follow-up clinical diagnosis and treatment of RVO patients. 展开更多
关键词 deep learning artificial intelligence Swin Transformer diagnostic model retinal vein occlusion color fundus photographs
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The Contribution of Hemispherical Photographs to Understand Natural Forest Regeneration in the AKAK Forest Area
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作者 Agbor James Ayamba Nkwatoh Athanasius Fuashi Kamah Pascal Bumtu 《Open Journal of Forestry》 2024年第3期313-326,共14页
Examining the contribution of hemispherical photographs in the understanding of Natural forest regeneration is very important in estimating the future forest structure, composition and to enforce conservation regulati... Examining the contribution of hemispherical photographs in the understanding of Natural forest regeneration is very important in estimating the future forest structure, composition and to enforce conservation regulations. This study sets out to examine the interaction between stump sprouting, LAI, site and canopy openness for the entire AKAK forest area and for the logging compartments;2013, 2015 and 2017 respectively. 49 sprouted stump were identified randonly. 20 m × 20 m plots were demarcated along a canopy gaps for each sprouted stump, the plots were established in such a manner that the sprouted stumps will be in the middle. For each of the selected 49 sprouted stump, indirect measurements of canopy cover were performed in the 49 plots of 20 m × 20 m (0.04 ha), giving a total of 1.96 ha of land covered. Galaxy S3 smartphone with a built-in Infinix ZERO 4 fish-eye lens with 198˚ view angle equidistant projection was used to take photos. The fish-eye lens was mounted on the phone camera and photograph were taken at a fixed height of 1.3 m. Results revealed that, the combine Principal Component Factor Analysis (2013, 2015 and 2017) of the correlation matrix for Sprout, Years, LAI 4%, LAI 5%, Canopy and Site openness, shows that factor 1 explained 62.6% of total variance while factor 2 explained 17.9% together explain 80.05% Communalities. For the year 2013, 2015 and 2017 respectively shows that there is a very strong correlation (p p < 0.0005) between LAI4 and LAI5. 展开更多
关键词 Hemispherical photographs Natural Forest Regeneration AKAK Forest
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Photographing of a Multi-Pellet Ablation Process in HL-1M Tokamak with CCD Camera
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作者 郑银甲 冯震 +7 位作者 李承跃 肖正贵 郭干成 李波 宋显明 付炳忠 李立 刘永 《Plasma Science and Technology》 SCIE EI CAS CSCD 2000年第1期95-103,共9页
The 2D CCD camera has been used to take photos during hydrogen multi-pellet injection in HL-1M tokamak. The hydrogen multi-pellet (2 × 1.0 mm, 3× 1.2 mm, 3×1.2 ~ 1.3 mm) is horizontally injected into ... The 2D CCD camera has been used to take photos during hydrogen multi-pellet injection in HL-1M tokamak. The hydrogen multi-pellet (2 × 1.0 mm, 3× 1.2 mm, 3×1.2 ~ 1.3 mm) is horizontally injected into plasma. The observation is performed above the injection path at a sight angle 13.4°,As the shape of cloud ablation varies so quickly, the key points of the experiment have to be the high temporal resolution of CCD and the determination of pellet radial location in plasma. A series of improvements have been made with the experiment setup, including camera parameter, control (NA, ROI) and trigger mode, so as to satisfy the experiment requirements. Thus very nice photos along with the satisfying experimental results are obtained such as: (1) single exposure time reduced to 100 us (2) multi-frame in one discharge (FPS≥ 40) (3)multi-exposure for one pellet so that further observation of the temporal process of pellet ablation may be possible. Through the data analysis on the spatial distibution of pellet ablation clouds in photos taken, the pellet dimensions, trajectory of the cloud and pellet velocity are obtained, and the physical mechanism of pellet-plasma interactions also analyzed. In particular, it is possible to provide an effective means for measuring q-profile of HL-1M plasma. 展开更多
关键词 photographing of a Multi-Pellet Ablation Process in HL-1M Tokamak with CCD Camera CCD HL
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Chinese Scientists "Photographed" Molecular Picture with Chemical Bond Resolution
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《Bulletin of the Chinese Academy of Sciences》 2001年第1期5-5,共1页
A flagship research project ofthe country during the Ninth Five-Year Plan period (1996-2000), thestudy was conducted under the ae-gis of CAS with financial supportfrom MOST. Remarkable academicprogress has been achiev... A flagship research project ofthe country during the Ninth Five-Year Plan period (1996-2000), thestudy was conducted under the ae-gis of CAS with financial supportfrom MOST. Remarkable academicprogress has been achieved over thepast years, according to the panel. 展开更多
关键词 gis Chinese Scientists Molecular Picture with Chemical Bond Resolution photographed MOST CAS
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Impacts of canopy structure on the sub-canopy solar radiation under a deciduous forest based on fisheye photographs
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作者 YanLin Zhang XiaoLin Feng +1 位作者 XiaoLi Chang LiMin Tie 《Research in Cold and Arid Regions》 CSCD 2023年第3期150-160,共11页
Forest canopy in a deciduous forest has significant sheltering effects on the sub-canopy solar radiation,significantly influencing the energy balance of snow and permafrost beneath the forest and their spatial distrib... Forest canopy in a deciduous forest has significant sheltering effects on the sub-canopy solar radiation,significantly influencing the energy balance of snow and permafrost beneath the forest and their spatial distribution.This study employs a digital camera mounted with a fisheye lens to acquire photographs at various times in a growth cycle of the forest canopy at three selected sites in a deciduous forest near the Greater Khingan Mountains Forest Ecological Station,Northeast China.The vegetation types and conditions at the selected sites include P1 in Ledum-Claopodium-L.dahurica,P2 in Carex tato-L.dahurica,and P3 in Betula fruticosa-L.dahurica.After necessary image processing,these photographs were used to identify the canopy structure and its impacts on the sub-canopy solar radiation.Results show that fisheye photographs can successfully capture the forest canopy structure and are useful in estimating the sub-canopy solar radiation.The order of sheltering effects from the largest to the smallest on sub-canopy solar radiation at three selected sites is P3,P1,and P2,highly depending on the canopy density.Then sub-canopy solar radiation was calculated using fisheye photographs and an algorithm validated by in-situ observed solar radiation beneath the canopy at P1 and P3.The results are reasonable,although the accuracy seems compromised due to the mismatch of conditions for calculation and observation.Results also show that the mean annual solar radiation above the canopy was about 148.3 W/m2 in 2018,and the mean annual solar radiation values beneath the canopy were about 90.0,123.8,and 61.0 W/m2 at P1,P2,and P3,with only 60%,84%,and 42%of the total solar radiation penetrating through the canopy,respectively.Even in winter,when the trees are leafless,the canopy sheltering effects cannot be ignored in dense forests.Despite the limitations,fisheye photographs and related algorithms are useful in investigating the forest canopy structure and its impacts on sub-canopy solar radiation. 展开更多
关键词 Solar radiation Forest structure Fisheye photograph Sub-canopy Deciduous forest
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野生动物摄影师:因热爱而发光
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作者 江丽 《疯狂英语(新悦读)》 2024年第1期11-13,74,共4页
大卫·普卢默是一位顶级的野生动物摄影师,一年中有几个月的时间他都在世界各地拍摄野生动物。1For David Plummer,wildlife and photography remained his passions.When he was 26,David took the leap to work towards becoming ... 大卫·普卢默是一位顶级的野生动物摄影师,一年中有几个月的时间他都在世界各地拍摄野生动物。1For David Plummer,wildlife and photography remained his passions.When he was 26,David took the leap to work towards becoming a professional wildlife photographer.“I moved to Sussex and did various odd jobs-which included cleaning and care work-in order to survive while I built my contacts and work experience,”he says.“Being a volun-teer photographer for the Sussex Wildlife Trust was a turning point.” 展开更多
关键词 TURNING BECOMING photograph
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从程序员到鸟类专家
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作者 黄文山 《疯狂英语(新读写)》 2024年第7期24-27,75,共5页
Born in Sichuan Province,Mei Jian now lives in Canada.He graduated from the Com⁃puter Science Department of Sun Yat⁃sen Uni⁃versity in 1992 and worked as a programmer.Encouraged by friends,he began bird⁃watching in 20... Born in Sichuan Province,Mei Jian now lives in Canada.He graduated from the Com⁃puter Science Department of Sun Yat⁃sen Uni⁃versity in 1992 and worked as a programmer.Encouraged by friends,he began bird⁃watching in 2016 and developed a fondness for bird pho⁃tography.However,he found that he was occa⁃sionally uncertain about what species he had photographed. 展开更多
关键词 CANADA photograph UNCERTAIN
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Hyperuricemia Accompanied with Changes in the Retinal Microcirculation in a Chinese High-risk Population for Diabetes 被引量:6
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作者 YUAN YuanZhi M. Kamran IKRAM +6 位作者 JIANG SunFang LIN HuanDong REN LiMin YAN HongMei SHENG JianHua CHEN XuSheng GAO Xin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第2期146-154,共9页
Objective To investigate the association of retinal vascular calibers with hyperuricemia in a middle‐aged and elderly population. Methods A cross‐sectional design was applied in this study and 869 participants aged ... Objective To investigate the association of retinal vascular calibers with hyperuricemia in a middle‐aged and elderly population. Methods A cross‐sectional design was applied in this study and 869 participants aged ≥40 years from a high‐risk group for diabetes were recruited. All participants received the anthropometrical measurements and laboratory tests. Retinal arteriolar and venular caliber of the participants were measured with a semi‐automated system. Hyperuricemia was defined as a serum uric acid level 420 μmol/L in men and 360 μmol/L in women. Linear regression models were used to assess the association of hyperuricemia with retinal vascular calibers. These models were additionally adjusted for age, central obesity, hypertension, dyslipidemia, weekly activity, smoking status, and education. Results Among the 869 participants, 133 (15.3%) suffered from hyperuricemia. The crude mean serum uric acid level was 312.3 μmol/L (Standard Deviation 79.5); mean concentration was 355.0 μmol/L (SD 75.5) in male participants, and 288.0 μmol/L (SD 71.1) in female participants (age‐adjusted difference 58.1 μmol/L, 95% Confidence Internal 48.5, 67.6). After adjusting for additional covariates, male participants with hyperuricemia had 3.77 μm (95% CI ‐0.46, 8.00) smaller arteriolar caliber and 6.20 μm (95% CI 0.36, 12.04) larger venule than those without hyperuricemia; the corresponding numbers among female participants were 1.57 μm (95% CI ‐1.07, 4.21) for retinal arteriolar caliber and 2.28 μm (95% CI ‐1.72, 6.27) for retinal venular caliber. Conclusion Hyperuricemia was associated with smaller retinal arteriolar caliber and larger venular caliber mainly in male participants in this study. 展开更多
关键词 Cardiovascular disease HYPERTENSION HYPERURICEMIA Metabolic syndrome Retinal photograph Retinal vessels Uric acid
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Vibration test of micro machined gyroscope based on high speed photography and SURF 被引量:1
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作者 姚峰林 高世桥 +1 位作者 赵婕 高崇仁 《Journal of Beijing Institute of Technology》 EI CAS 2012年第2期179-184,共6页
Based on three kinds of dynamic test of MEMS, a dynamic system for the vibration test of micro machined gyroscope based on high speed photography is introduced. Firstly, the architecture of the system hardware is intr... Based on three kinds of dynamic test of MEMS, a dynamic system for the vibration test of micro machined gyroscope based on high speed photography is introduced. Firstly, the architecture of the system hardware is introduced. Secondly, the image tracking performance is compared by the test using the template matching algorithm, the mean shift algorithm and the SURF algorithm. The vibration curve shows that high speed photograph combined with SURF algorithm is faster, more ac- curate, and more suitable for the vibration test of micro machined gyroscope. After the frequency a- nalysis and related interpolation, more characteristics of micro gyroscope can be obtained. 展开更多
关键词 high speed photograph SURF micro machined gyroscope dynamic test VIBRATION IMAGE
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A Digital Photographic Technique for Knee Range of Motion Measurement: Performance in a Total Knee Arthroplasty Clinical Population
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作者 Michael Murphy Julie Hides Trevor Russell 《Open Journal of Orthopedics》 2013年第1期4-9,共6页
Background: Knee range of motion is an essential outcome measure following total knee arthroplasty and it is important to measure this outcome with a simple and accurate tool. Measurement from digital photographs coul... Background: Knee range of motion is an essential outcome measure following total knee arthroplasty and it is important to measure this outcome with a simple and accurate tool. Measurement from digital photographs could provide a superior clinical alternative to the common goniometer as devices for capturing digital photographs are becoming more accessible, measurement accuracy is assisted with the associated software and images can be saved and stored for later reference. This ability to store images with measurements could be particularly useful in research involving knee range of motion. This study evaluated the validity and reliability of a simple photographic measurement technique to measure knee flexion and extension of patients following knee arthroplasty.Methods: Knee flexion and extension of 38 subjects who had undergone total knee arthroplasty were assessed at the one year post-operative review with the digital technique and a universal goniometer as the criterion reference. Digital measurements were repeated one month later by the first assessor (intra-tester reliability) and another independent assessor (inter-tester reliability).Results: Validity: the digital technique was found to have a high level of agreement with the universal goniometer measurements (all MAD sion with almost perfect Intra-Class Correlations (Intra-tester;flexion 0.99, extension 0.96;inter-tester;flexion 0.97, extension 0.93).Conclusion: Measurement of knee range of motion from digital photographs can be used in routine clinical total knee arthroplasty follow-up instead of, or interchangeably with the universal goniometer. 展开更多
关键词 KNEE Range of Motion ARTHROPLASTY DIGITAL photographic GONIOMETRY
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Photographic Image: Thematization of Its Discourses
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作者 Ricardo Crisafulli Rodrigues 《Journal of Signal and Information Processing》 2013年第4期414-422,共9页
This paper deals with thematization as a fundamental step towards the determination of photography image discourses in order to index them. It deals with questions related to photographic reality, polysemy, denotation... This paper deals with thematization as a fundamental step towards the determination of photography image discourses in order to index them. It deals with questions related to photographic reality, polysemy, denotation and connotation, whose comprehension is fundamentally important for the interpretation of photography discourses. It also approaches aspects that have influenced photography analysis towards its thematization, such as the characterization of an image bank, the functions performed by photos, as well as technical and visual quality. 展开更多
关键词 Descriptive ANALYSIS Interpretative ANALYSIS photographic Connotation photographic DENOTATION Imagetic Discourses THEMATIC Discourses photography IMAGE photographic IMAGE POLYSEMY of photographic IMAGE photographic REFERENT Thematization Thematization of photographic IMAGE Thematization and Indexing
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NUMERICAL ANALYSIS AND VISUALIZATION OF NATURAL GAS JET WITH MULTI-POINT INJECTION SYSTEM
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作者 Xu Boyan Liang Fuyou Cai Shaoli 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期550-554,共5页
Aiming at the change in intake air flow caused by the injection of natural gas in intake manifold if one simply replaces the gasoline injector with natural gas injector with the installing position of injector in inta... Aiming at the change in intake air flow caused by the injection of natural gas in intake manifold if one simply replaces the gasoline injector with natural gas injector with the installing position of injector in intake manifold unchanged, and also the reflection of gas toward intake manifold inlet resulted from the impingement between the injected large volumetric natural gas jet and intake valve, an impulsively started natural gas jet injected from a gas injector is characterized as a three-dimensional unsteady compressible viscous turbulent flow, based on which its transient development process is numerically analyzed using general-purpose CFD codes. The predicted velocity vector maps show a vortex, which indicates the occurrence of an unsteady state jet region, is formed downstream of the jet. A schlieren apparatus is utilized to get several groups of visible schlieren photographs of natural gas jets. In the experiment, photographs of natural gas jets taken by a CCD camera are laid in a portrait processor where the shapes, tip penetration distance and injection angles of the gas jets are investigated. Comparisons between predicted results and measurements indicate an excellent agreement between simulations and experimental results. 展开更多
关键词 Natural gas injector Jet Numerical analysis Schlieren photograph
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Illustration of Cover Photographs
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《Paper And Biomaterials》 2017年第3期41-41,共1页
The cellulose solution was prepared by dissolving cellulose in alkali/urea or thiourea aqueous system at low temperature.Then,the cellulose solution was treated through different processing technologies such as electr... The cellulose solution was prepared by dissolving cellulose in alkali/urea or thiourea aqueous system at low temperature.Then,the cellulose solution was treated through different processing technologies such as electrospinning method,sol-gel transition method,optimal extrusion dropping technology, 展开更多
关键词 of in ET Illustration of Cover photographs been ACS
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What Can We Learn from Photographs?
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作者 单祝堂 《语言教育》 1993年第3期33-35,共3页
In this country, lots of people like to take photographs.We can see photographs bulging from wallets andalbums; fall from drawers and closets; clutter up desktops and wall space; fill countless frames and slideproject... In this country, lots of people like to take photographs.We can see photographs bulging from wallets andalbums; fall from drawers and closets; clutter up desktops and wall space; fill countless frames and slideprojectors. Most of them are visual records of ourfamilies extending back through generations and inclu- 展开更多
关键词 CLUTTER FRAMES inclu viewing photograph LOOKING records SMILE apply STAND
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FROM GUEST TO FRIEND--China-ASEAN Expo in the eyes of a Bruneian photographer
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作者 Jeffrey Wong 《China Report ASEAN》 2019年第9期74-75,共2页
A Chinese saying goes,“Nothing, not even mountains and oceans, can separate people with shared goals and vision.” With the theme “Building Belt and Road Routes, Realizing Our Vision for a Community of Shared Future... A Chinese saying goes,“Nothing, not even mountains and oceans, can separate people with shared goals and vision.” With the theme “Building Belt and Road Routes, Realizing Our Vision for a Community of Shared Future,” the 16th China- ASEAN Expo (CAEXPO) was held from September 20 to 23 in Nanning, the capital city of Guangxi Zhuang Autonomous Region in southern China. 展开更多
关键词 CHINA-ASEAN EXPO Bruneian photographER
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Flying Freely in a Black-and-White World——Young photographer Wen Hengmin
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作者 YiRen PhotobyWenHengmin 《China & The World Cultural Exchange》 2002年第5期28-31,共4页
Foreign tourists to Beijing aspire to do three things -?climb the Great Wall, eat Beijing roast duck and visit the Panjiayuan flea market. On weekends, the Panjiayuan market attracts thousands of shoppers, both Chines... Foreign tourists to Beijing aspire to do three things -?climb the Great Wall, eat Beijing roast duck and visit the Panjiayuan flea market. On weekends, the Panjiayuan market attracts thousands of shoppers, both Chinese and foreign. In one corner a unique stand sells pictures. Displayed on one wall and grouped on a table are dozens of black-and-white photographs of folk customs in simple but elegant frames, just like at a photographic exhibition. Many people - 展开更多
关键词 Young photographer Wen Hengmin In Flying Freely in a Black-and-White World
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1996 The First KONGYUYAN JIU CUP China Traditional Opera International Photographic Competition Collecting Photographic Works Information
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《China & The World Cultural Exchange》 1996年第2期46-46,共1页
关键词 CUP The First KONGYUYAN JIU CUP China Traditional Opera International photographic Competition Collecting photographic Works Information
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系统功能语言学视角下Dianne Wolfer的作品Photographs in the Mud的及物性分析
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作者 方小花 《海外英语》 2019年第14期81-82,共2页
Photographs in the Mud是澳大利亚作家Dianne Wolfer的第一部图画书,该书从一个澳大利亚士兵和一个日本士兵以及远方等待他们平安归来的家庭三者的角度描述了二战中太平洋科科达战役的一场战斗。通过言语交流让这两个不同阵营的士兵产... Photographs in the Mud是澳大利亚作家Dianne Wolfer的第一部图画书,该书从一个澳大利亚士兵和一个日本士兵以及远方等待他们平安归来的家庭三者的角度描述了二战中太平洋科科达战役的一场战斗。通过言语交流让这两个不同阵营的士兵产生共鸣。及物性在刻画人物和篇章衔接方面起关键作用。因此该文通过运用系统功能语言学及物性系统的六大过程对本书选段进行了分析,得出文字背后隐含的深层含义,即士兵面对国家义务和家人责任之间选择的矛盾,他们内心厌恶战争却又不得不为了自己的国家而参战的矛盾,反映出战争不仅给两个士兵还有他们的家人造成的悲剧的新思考。 展开更多
关键词 photographs in the MUD 及物性 过程 语篇分析
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The Forbidden City Through the Eyes of a Photographer──A new look at something old
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《China Today》 1998年第8期46-47,共2页
TheForbiddenCityThroughtheEyesofaPhotographer──Anewlookatsomethingold.BystaffreporterRENYINGTHEForbiddenCity... TheForbiddenCityThroughtheEyesofaPhotographer──Anewlookatsomethingold.BystaffreporterRENYINGTHEForbiddenCityislilkearolloffil... 展开更多
关键词 photographER the THROUGH
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Photographic Exhibition"China: Fifty Years Inside the People's Republic"Held in Beijing
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《China & The World Cultural Exchange》 2000年第1期42-42,共1页
关键词 Fifty Years Inside the People’s Republic"Held in Beijing photographic Exhibition"China
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