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北方冷季型草坪草耐盐能力的测定 被引量:14
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作者 牛菊兰 《草地学报》 CAS CSCD 1997年第3期190-194,共5页
本项研究以我国北方地区硫酸盐-氧化物盐土主要含有的Na2SO4和NaCl对冷季型草坪草3个属的10个品种进行萌发期耐盐能力的评比,确定了测试品种种子发芽时耐盐的临界值,并依值的大小将耐盐性从强到弱进行排序,结果是:早熟禾品种以优异... 本项研究以我国北方地区硫酸盐-氧化物盐土主要含有的Na2SO4和NaCl对冷季型草坪草3个属的10个品种进行萌发期耐盐能力的评比,确定了测试品种种子发芽时耐盐的临界值,并依值的大小将耐盐性从强到弱进行排序,结果是:早熟禾品种以优异、梅里安和塞伯3个品种耐盐性较强,匍匐紫羊茅和匍茎翦股颖两品种的耐盐性强于细弱翦股颖和早熟禾各个品种。对主要建坪种的早熟禾品种在较重盐渍土壤(平均全盐含量0.617%)上进行了小区种植耐盐鉴定。通过对早熟禾6个品种在单位盐浓度上的盖度、地上、地下、植物量、草坪质量评比记分和萌发期耐盐能力的综合评比,筛选出评用质量化,耐盐能力强的品种是:优异、梅里安和爱肯尼。 展开更多
关键词 冷季型 草坪草 萌发期 种植 耐盐能力
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中西方文化中的乌鸦意象探析 被引量:10
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作者 冯静 《齐鲁学刊》 CSSCI 北大核心 2002年第5期99-101,共3页
乌鸦意象在中国文化和西方文化中都具有丰富而又复杂的文化内涵。东西方文化对乌鸦的不同态度表明各民族文化中的乌鸦意象有着各自不同的文化渊源。同时 ,东西方文化赋予乌鸦的感情色彩及其相应的文化内涵又存在许多相通之处。
关键词 中西方文化 乌鸦 乌鸦意象
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论诗集《乌鸦》主人公的角色变迁 被引量:8
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作者 刘国清 《山东外语教学》 2004年第5期88-90,94,共4页
英国已故桂冠诗人泰德·休斯的力作<乌鸦>叙述了主人公乌鸦的成长历程.诗集从乌鸦的诞生一直写到他与自然结为连理,其间乌鸦历经旁观者、破坏者、受害者与醒悟者的角色变迁,既反省批判了理性主义的罪愆,也警示了理性主义泛滥... 英国已故桂冠诗人泰德·休斯的力作<乌鸦>叙述了主人公乌鸦的成长历程.诗集从乌鸦的诞生一直写到他与自然结为连理,其间乌鸦历经旁观者、破坏者、受害者与醒悟者的角色变迁,既反省批判了理性主义的罪愆,也警示了理性主义泛滥的潜在危险,并展望了人与自然重归和谐的美好未来,让人们看到了解决人类生存危机的曙光. 展开更多
关键词 《乌鸦》 主人公 角色变迁
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从西夏文“■·jow”说起——兼谈夏汉之间的文化交流
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作者 唐晓宁 《西夏研究》 2024年第1期12-21,共10页
汉译佛教文本中“三十二相、八十种好”借用一些动物来表现佛陀的庄严之姿,如鹿王、狮子、大象、鹅王等,但是在以藏文为底本翻译成西夏文的俄藏5130号《胜慧彼岸到要门教授现前解庄严论诠颂》中却用了“■·jow”来翻译汉译中的“... 汉译佛教文本中“三十二相、八十种好”借用一些动物来表现佛陀的庄严之姿,如鹿王、狮子、大象、鹅王等,但是在以藏文为底本翻译成西夏文的俄藏5130号《胜慧彼岸到要门教授现前解庄严论诠颂》中却用了“■·jow”来翻译汉译中的“鹅王”,而西夏文“■·jow”的意思是“乌(鸦),一种黑色的鸟”。因此本文主要从“■·jow”在西夏文本中的使用实例说起,结合考古、图像等多种资料追本溯源,探究西夏人民对于乌鸦形象的认知来源,得出主要源于三个汉地传统的结论,并进一步探究西夏翻译者将西夏文“■·jow”对译为汉文“鹅王”背后隐藏的历史文化信息。 展开更多
关键词 鹅王 太阳-乌 汉地传统
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Enterococcus faecalis provides protection during scavenging in carrion crow (Corvus corone)
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作者 Bin Hu Jia-Min Wang +5 位作者 Qing-Xun Zhang Jing Xu Ya-Nan Xing Bo Wang Shu-Yi Han Hong-Xuan He 《Zoological Research》 SCIE CSCD 2024年第3期451-463,共13页
The gut microbiota significantly influences host physiology and provides essential ecosystem services.While diet can affect the composition of the gut microbiota,the gut microbiota can also help the host adapt to spec... The gut microbiota significantly influences host physiology and provides essential ecosystem services.While diet can affect the composition of the gut microbiota,the gut microbiota can also help the host adapt to specific dietary habits.The carrion crow(Corvus corone),an urban facultative scavenger bird,hosts an abundance of pathogens due to its scavenging behavior.Despite this,carrion crows infrequently exhibit illness,a phenomenon related to their unique physiological adaptability.At present,however,the role of the gut microbiota remains incompletely understood.In this study,we performed a comparative analysis using 16S rRNA amplicon sequencing technology to assess colonic content in carrion crows and 16 other bird species with different diets in Beijing,China.Our findings revealed that the dominant gut microbiota in carrion crows was primarily composed of Proteobacteria(75.51%)and Firmicutes(22.37%).Significant differences were observed in the relative abundance of Enterococcus faecalis among groups,highlighting its potential as a biomarker of facultative scavenging behavior in carrion crows.Subsequently,E.faecalis isolated from carrion crows was transplanted into model mice to explore the protective effects of this bacterial community against Salmonella enterica infection.Results showed that E.faecalis down-regulated the expression of pro-inflammatory cytokines tumor necrosis factor alpha(TNF-α),interferon gamma(IFN-γ),and interleukin 6(IL-6),prevented S.enterica colonization,and regulated the composition of gut microbiota in mice,thereby modulating the host’s immune regulatory capacity.Therefore,E.faecalis exerts immunoregulatory and anti-pathogenic functions in carrion crows engaged in scavenging behavior,offering a representative case of how the gut microbiota contributes to the protection of hosts with specialized diets. 展开更多
关键词 Carrion crow Facultative scavenger Gut microbiota Enterococcus faecalis 16S rRNA sequencing
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A Real-time Lithological Identification Method based on SMOTE-Tomek and ICSA Optimization
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作者 DENG Song PAN Haoyu +5 位作者 LI Chaowei YAN Xiaopeng WANG Jiangshuai SHI Lin PEI Chunyu CAI Meng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期518-530,共13页
In petroleum engineering,real-time lithology identification is very important for reservoir evaluation,drilling decisions and petroleum geological exploration.A lithology identification method while drilling based on ... In petroleum engineering,real-time lithology identification is very important for reservoir evaluation,drilling decisions and petroleum geological exploration.A lithology identification method while drilling based on machine learning and mud logging data is studied in this paper.This method can effectively utilize downhole parameters collected in real-time during drilling,to identify lithology in real-time and provide a reference for optimization of drilling parameters.Given the imbalance of lithology samples,the synthetic minority over-sampling technique(SMOTE)and Tomek link were used to balance the sample number of five lithologies.Meanwhile,this paper introduces Tent map,random opposition-based learning and dynamic perceived probability to the original crow search algorithm(CSA),and establishes an improved crow search algorithm(ICSA).In this paper,ICSA is used to optimize the hyperparameter combination of random forest(RF),extremely random trees(ET),extreme gradient boosting(XGB),and light gradient boosting machine(LGBM)models.In addition,this study combines the recognition advantages of the four models.The accuracy of lithology identification by the weighted average probability model reaches 0.877.The study of this paper realizes high-precision real-time lithology identification method,which can provide lithology reference for the drilling process. 展开更多
关键词 mud logging data real-time lithological identification improved crow search algorithm petroleum geological exploration SMOTE-Tomek
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“三足乌”起源考 被引量:3
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作者 田冬梅 张颖夫 《唐山师范学院学报》 2010年第6期38-39,57,共3页
许多学者认为"三足乌"起源于远古时期的太阳崇拜和图腾崇拜,即源于《山海经》中的"阳乌载日"神话,其实不然。从考古学和文献学角度论证最初之阳乌并非"三足","三足乌"是汉代儒学与阴阳术数相... 许多学者认为"三足乌"起源于远古时期的太阳崇拜和图腾崇拜,即源于《山海经》中的"阳乌载日"神话,其实不然。从考古学和文献学角度论证最初之阳乌并非"三足","三足乌"是汉代儒学与阴阳术数相结合的产物。 展开更多
关键词 阳乌 三足乌 汉代
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Scale Invariant Feature Transform with Crow Optimization for Breast Cancer Detection 被引量:1
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作者 A.Selvi S.Thilagamani 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2973-2987,共15页
Mammography is considered a significant image for accurate breast cancer detection.Content-based image retrieval(CBIR)contributes to classifying the query mammography image and retrieves similar mammographic images fr... Mammography is considered a significant image for accurate breast cancer detection.Content-based image retrieval(CBIR)contributes to classifying the query mammography image and retrieves similar mammographic images from the database.This CBIR system helps a physician to give better treatment.Local features must be described with the input images to retrieve similar images.Exist-ing methods are inefficient and inaccurate by failing in local features analysis.Hence,efficient digital mammography image retrieval needs to be implemented.This paper proposed reliable recovery of the mammographic image from the data-base,which requires the removal of noise using Kalman filter and scale-invariant feature transform(SIFT)for feature extraction with Crow Search Optimization-based the deep belief network(CSO-DBN).This proposed technique decreases the complexity,cost,energy,and time consumption.Training the proposed model using a deep belief network and validation is performed.Finally,the testing pro-cess gives better performance compared to existing techniques.The accuracy rate of the proposed work CSO-DBN is 0.9344,whereas the support vector machine(SVM)(0.5434),naïve Bayes(NB)(0.7014),Butterfly Optimization Algorithm(BOA)(0.8156),and Cat Swarm Optimization(CSO)(0.8852). 展开更多
关键词 SIFT Kalman filter crow search optimization deep neural network noise removal
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文化区系视野下的上古砭石疗法起源初探 被引量:5
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作者 袁婷 王振国 《世界科学技术-中医药现代化》 2015年第12期2502-2507,共6页
《黄帝内经》"异法方宜论"记载的中医起源五方论的真实性在学术界仍存在很大争议,本文以"中国考古学文化区系类型学说"为新视角,从东方东夷部族的地域文化入手,分析东夷文化中的弓箭传统、酿酒技术、神乌信仰、开... 《黄帝内经》"异法方宜论"记载的中医起源五方论的真实性在学术界仍存在很大争议,本文以"中国考古学文化区系类型学说"为新视角,从东方东夷部族的地域文化入手,分析东夷文化中的弓箭传统、酿酒技术、神乌信仰、开颅手术和文身习俗,通过对"砭"、"醫"、"鹊"三字的训诂,揭示上古砭石疗法与东夷文明和神医扁鹊之间的复杂关系,提出上古砭石疗法起源于东夷文明的新证据和新观点。 展开更多
关键词 砭石 东夷 扁鹊 乌鸦 中医起源 文化区系
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Use of Detailed Topographic Map Evidence of the Southeast Wyoming Gangplank Area to Compare Two Fundamentally Different Geomorphology Paradigms, USA 被引量:2
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作者 Eric Clausen 《Open Journal of Geology》 2020年第4期261-279,共19页
Drainage divides along a southern Laramie Range crest area and in the nearby southeast Wyoming Gangplank area (as observed on detailed topographic maps) suggest present-day drainage routes in the Cheyenne Tablelands r... Drainage divides along a southern Laramie Range crest area and in the nearby southeast Wyoming Gangplank area (as observed on detailed topographic maps) suggest present-day drainage routes in the Cheyenne Tablelands region originated as headward erosion of south-oriented valleys (now the downstream Lodgepole, Crow, and Lone Tree Creek valleys) from an actively eroding northeast-oriented South Platte River valley captured flood flow in the south half of a large east-oriented anastomosing channel complex while headward erosion of a north-oriented valley (now the downstream Horse Creek valley) from the southeast-oriented North Platte River valley captured the north half of the same large anastomosing channel complex. The Gangplank, which today serves as a low gradient ramp of Tertiary Ogallala Formation sediments leading from the Great Plains to the Laramie Range erosion surface, is located along the Crow Creek-Lone Tree Creek drainage divide and low points along that divide (referred to here as divide crossings) suggest, prior to headward erosion of what is now its south-oriented downstream Lone Tree Creek valley, upstream east-oriented Lone Tree Creek drainage routes were intertwined with east-oriented Crow Creek drainage routes, which today flow much further in an east direction (than east-oriented upstream Lone Tree Creek drainage routes) before also turning in a south direction to reach the South Platte River. The ability of the commonly accepted regional geomorphology paradigm to explain this topographic map evidence is then compared with a fundamentally different and new regional geomorphology paradigm’s ability to explain the same evidence. While both paradigms offer possible explanations the new paradigm, which requires headward erosion of the valleys to have occurred as massive continental ice sheet melt water floods crossed the region, explains much more of the drainage system evidence and also permits much more detailed explanations. 展开更多
关键词 Anastomosing Channel Complex Cheyenne Tablelands crow CREEK Drainage DIVIDE Great PLAINS Laramie Range Lone Tree CREEK South Platte River
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从乌鸦形象内涵看中日文化差异 被引量:4
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作者 彭仁煌 《科教导刊》 2012年第5期226-227,共2页
乌鸦在中日两国中有着不同的形象内涵。在中国,乌鸦是不祥之兆;在日本,乌鸦被奉为神鸟。本文运用文献资料、比较研究等方法对两国乌鸦形象的内涵进行了探讨,解析乌鸦在两国中不同的文化内涵。希望通过这种对比,使得我们在与日本人的交... 乌鸦在中日两国中有着不同的形象内涵。在中国,乌鸦是不祥之兆;在日本,乌鸦被奉为神鸟。本文运用文献资料、比较研究等方法对两国乌鸦形象的内涵进行了探讨,解析乌鸦在两国中不同的文化内涵。希望通过这种对比,使得我们在与日本人的交往中避免或减少尴尬及语言冲撞。 展开更多
关键词 乌鸦 形象内涵 对比 文化冲撞
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Scale Invariant Feature Transform with Crow Optimization for Breast Cancer Detection
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作者 A.Selvi S.Thilagaman 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1257-1272,共16页
Mammography is considered a significant image for accurate breast cancer detection.Content-based image retrieval(CBIR)contributes to classifying the query mammography image and retrieves similar mammographic images fro... Mammography is considered a significant image for accurate breast cancer detection.Content-based image retrieval(CBIR)contributes to classifying the query mammography image and retrieves similar mammographic images from the database.This CBIR system helps a physician to give better treatment.Local features must be described with the input images to retrieve similar images.Exist-ing methods are inefficient and inaccurate by failing in local features analysis.Hence,efficient digital mammography image retrieval needs to be implemented.This paper proposed reliable recovery of the mammographic image from the data-base,which requires the removal of noise using Kalmanfilter and scale-invariant feature transform(SIFT)for feature extraction with Crow Search Optimization-based the deep belief network(CSO-DBN).This proposed technique decreases the complexity,cost,energy,and time consumption.Training the proposed model using a deep belief network and validation is performed.Finally,the testing pro-cess gives better performance compared to existing techniques.The accuracy rate of the proposed work CSO-DBN is 0.9344,whereas the support vector machine(SVM)(0.5434),naïve Bayes(NB)(0.7014),Butterfly Optimization Algorithm(BOA)(0.8156),and Cat Swarm Optimization(CSO)(0.8852). 展开更多
关键词 SIFT Kalmanfilter crow search optimization deep neural network noise removal
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Selective Mapping Scheme for Universal Filtered Multicarrier
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作者 Akku Madhusudhan Sudhir Kumar Sharma 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1273-1282,共10页
The next step in mobile communication technology,known as 5G,is set to go live in a number of countries in the near future.New wireless applica-tions have high data rates and mobility requirements,which have posed a c... The next step in mobile communication technology,known as 5G,is set to go live in a number of countries in the near future.New wireless applica-tions have high data rates and mobility requirements,which have posed a chal-lenge to mobile communication technology researchers and designers.5G systems could benefit from the Universal Filtered Multicarrier(UFMC).UFMC is an alternate waveform to orthogonal frequency-division multiplexing(OFDM),infiltering process is performed for a sub-band of subcarriers rather than the entire band of subcarriers Inter Carrier Interference(ICI)between neighbouring users is reduced via the sub-bandfiltering process,which reduces out-of-band emissions.However,the UFMC system has a high Peak-to-Average Power Ratio(PAPR),which limits its capabilities.Metaheuristic optimization based Selective mapping(SLM)is used in this paper to optimise the UFMC-PAPR.Based on the cognitive behaviour of crows,the research study suggests an innovative metaheuristic opti-mization known as Crow Search Algorithm(CSA)for SLM optimization.Com-pared to the standard UFMC,SLM-UFMC system,and SLM-UFMC with conventional metaheuristic optimization techniques,the suggested technique sig-nificantly reduces PAPR.For the UFMC system,the suggested approach has a very low Bit Error Rate(BER). 展开更多
关键词 -Universalfiltered multicarrier(UFMC) selective mapping(SLM) metaheuristic optimization crow search algorithm(CSA) bit error rate(BER)
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Improved Interleaved Single-Ended Primary Inductor-Converter forSingle-Phase Grid-Connected System
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作者 T.J.Thomas Thangam K.Muthu Vel 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3459-3478,共20页
The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated fr... The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated from the PV system is erratic and hence there is a need for an efficient converter to perform the extraction of maximum power.An improved interleaved Single-ended Primary Inductor-Converter(SEPIC)converter is employed in proposed work to extricate most of power from renewable source.This proposed converter minimizes ripples,reduces electromagnetic interference due tofilter elements and the contin-uous input current improves the power output of PV panel.A Crow Search Algo-rithm(CSA)based Proportional Integral(PI)controller is utilized for controlling the converter switches effectively by optimizing the parameters of PI controller.The optimized PI controller reduces ripples present in Direct Current(DC)vol-tage,maintains constant voltage at proposed converter output and reduces over-shoots with minimum settling and rise time.This voltage is given to single phase grid via 1�Voltage Source Inverter(VSI).The command pulses of 1�VSI are produced by simple PI controller.The response of the proposed converter is thus improved with less input current.After implementing CSA based PI the efficiency of proposed converter obtained is 96%and the Total Harmonic Distor-tion(THD)is found to be 2:4%.The dynamics and closed loop operation is designed and modeled using MATLAB Simulink tool and its behavior is performed. 展开更多
关键词 Improved interleaved DC-DC SEPIC converter crow search algorithm PI controller voltage source inverter PV array single phase grid
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The Historical and Current Characteristics of“Plague Writing”-Rereading Chi Zijian’s Novel White Snow Crow in the Post Epidemic Era
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作者 LIU Shihao 《Cultural and Religious Studies》 2023年第8期343-350,共8页
Chi Zijian’s novel White Snow Crow is about the pestis in Northeast China from the autumn and winter of 1910 to the spring of 1911,focusing on the living conditions of people in Fujiadian,Harbin,under the shadow of t... Chi Zijian’s novel White Snow Crow is about the pestis in Northeast China from the autumn and winter of 1910 to the spring of 1911,focusing on the living conditions of people in Fujiadian,Harbin,under the shadow of the pestis,and thus connects the vicissitudes of Harbin in the development of modern Chinese history.Re-reading this novel in the context of the post-epidemic era not only allows us to immerse ourselves in the specific temporal and spatial fields described in the text with an immersive reading mindset,feel the heavy impact that the disaster has brought to the people of Northeast China,but also provide us with a different perspective to observe the current social reality.In particular,the social problems shown by the novel through the pestis and the description of ordinary people’s life experience under the plague still deserve further discussion. 展开更多
关键词 Chi Zijian plague writing White Snow crow post pandemic era
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中国古典诗歌中喜乌意象的成因及其美学意义 被引量:3
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作者 陈金琳 曾凡解 《湘南学院学报》 2005年第4期59-60,66,共3页
乌鸦意象是中国文学中一种比较重要的禽乌意象。从民俗文化及审美心理的角度来考察,喜乌意象生成是我国早期民俗审美中实用、功利色彩的必然反映。
关键词 乌鸦 意象 审美意义
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网络时代的文学及女性话语权力——兼评九丹的《乌鸦》 被引量:2
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作者 马明艳 《内蒙古师范大学学报(哲学社会科学版)》 2002年第6期92-94,共3页
 九丹用《乌鸦》打破了一段时间以来文坛的沉寂,以"身体写作"为卖点主动迎合所谓的"时尚"。九丹和《乌鸦》的走俏既不体现文学的价值,也不代表女性话语权力的增强,却恰恰证明了网络时代文学魅力的衰落、文学传统...  九丹用《乌鸦》打破了一段时间以来文坛的沉寂,以"身体写作"为卖点主动迎合所谓的"时尚"。九丹和《乌鸦》的走俏既不体现文学的价值,也不代表女性话语权力的增强,却恰恰证明了网络时代文学魅力的衰落、文学传统功能的降低以及男性话语霸权的根深蒂固。 展开更多
关键词 网络时代 女性话语权力 九丹 《乌鸦》 '身体写作' 小说
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论塔特·休斯《乌鸦》中的意象特质 被引量:3
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作者 李成坚 《天津外国语学院学报》 2000年第1期53-56,共4页
《乌鸦》是当代英国诗坛最负盛名的诗人塔特·休斯的第四部诗集、代表作。《乌鸦》以其主体意象模式、独特的形象造型和语言特征 ,成为一部后现代视域下的实验拓新 ,实现了诗人“风格的尝试”。这种尝试既反映出英国战后文学发展的... 《乌鸦》是当代英国诗坛最负盛名的诗人塔特·休斯的第四部诗集、代表作。《乌鸦》以其主体意象模式、独特的形象造型和语言特征 ,成为一部后现代视域下的实验拓新 ,实现了诗人“风格的尝试”。这种尝试既反映出英国战后文学发展的趋同性 ,又分明突出了诗人的个性化。 展开更多
关键词 《乌鸦》 诗人 休斯 诗坛 战后文学 主体意象 当代 尝试 英国 代表作
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A Single Arm, Monocentric, Prospective, Open Label Study to Evaluate Anti-Ageing Efficacy of Human Growth Factors and Cytokines Containing Cosmetic Skin Serum in Indian Female Population
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作者 Mukta Sachdev Anoop Chullikana +6 位作者 Raviraja N. Seetharam Rachana Shilpakar R. Sapna Keerthi Velugotla Ritambhara   Anish S. Majumdar Pawan Kumar Gupta 《Journal of Cosmetics, Dermatological Sciences and Applications》 2017年第1期118-132,共15页
Introduction: The use of growth factors and cytokines in skin rejuvenation and reversal of photo ageing is a novel anti-ageing treatment. These factors provide a microenvironment that seems to favor tissue repair and ... Introduction: The use of growth factors and cytokines in skin rejuvenation and reversal of photo ageing is a novel anti-ageing treatment. These factors provide a microenvironment that seems to favor tissue repair and regeneration. Methods: An open label, monocentric, single arm study to evaluate anti-ageing efficacy of conditioned medium obtained from adult human bone-marrow derived allogenic mesenchymal stromal cells (BMMSC) along with excipients formulated into a cosmetic serum, was conducted in 40 Indian female population aged 35 to 60 years, belonging to skin type IV - VI of Norwood Scale for a duration of 90 days. Parameters—fine lines, wrinkles, crow’s feet, evenness of skin tone, skin firmness/laxity, hydration of skin, homogeneity of age spots, and visible pores were used to evaluate the anti-ageing and rejuvenating properties of the test product. Results and Discussion: Improvement was seen in majority of parameters starting from 15 - 30 days. Product was safe and well tolerated as per the dermatologist and subjects’ self-assessment. 展开更多
关键词 CYTOKINES Conditioned Media crow’s FEET ANTI-AGEING
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Optimal Allocation of a Hybrid Wind Energy-Fuel Cell System Using Different Optimization Techniques in the Egyptian Distribution Network
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作者 Adel A. Abou El-Ela Sohir M. Allam Nermine K. Shehata 《Energy and Power Engineering》 2021年第1期17-40,共24页
This paper presents an optimal proposed allocating procedure for hybrid wind energy combined with proton exchange membrane fuel cell (WE/PEMFC) system to improve the operation performance of the electrical distributio... This paper presents an optimal proposed allocating procedure for hybrid wind energy combined with proton exchange membrane fuel cell (WE/PEMFC) system to improve the operation performance of the electrical distribution system (EDS). Egypt has an excellent wind regime with wind speeds of about 10 m/s at many areas. The disadvantage of wind energy is its seasonal variations. So, if wind power is to supply a significant portion of the demand, either backup power or electrical energy storage (EES) system is needed to ensure that loads will be supplied in reliable way. So, the hybrid WE/PEMFC system is designed to completely supply a part of the Egyptian distribution system, in attempt to isolate it from the grid. However, the optimal allocation of the hybrid units is obtained, in order to enhance their benefits in the distribution networks. The critical buses that are necessary to install the hybrid WE/ PEMFC system, are chosen using sensitivity analysis. Then, the binary Crow search algorithm (BCSA), discrete Jaya algorithm (DJA) and binary particle swarm optimization (BPSO) techniques are proposed to determine the optimal operation of power systems using single and multi-objective functions (SOF/MOF). Then, the results of the three optimization techniques are compared with each other. Three sensitivity factors are employed in this paper, which are voltage sensitivity factor (VSF), active losses sensitivity factor (ALSF) and reactive losses sensitivity factor (RLSF). The effects of the sensitivity factors (SFs) on the SOF/MOF are studied. The improvement of voltage profile and minimizing active and reactive power losses of the EDS are considered as objective functions. Backward/forward sweep (BFS) method is used for the load flow calculations. The system load demand is predicted up to year 2022 for Mersi-Matrouh City as a part of Egyptian distribution network, and the design of the hybrid WE/PEMFC system is applied. The PEMFC system is designed considering simplified mathematical expressions. The economics of operat 展开更多
关键词 Wind Energy System Proton Exchange Membrane Fuel Cell Binary crow Search Algorithm Discrete Jaya Algorithm Binary Particle Swarm Optimization Technique
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