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ACtriplet:An improved deep learning model for activity cliffs prediction by integrating triplet loss and pre-training 被引量:1
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作者 Xinxin Yu Yimeng Wang +3 位作者 Long Chen Weihua Li Yun Tang Guixia Liu 《Journal of Pharmaceutical Analysis》 2025年第8期1837-1847,共11页
Activity cliffs(ACs)are generally defined as pairs of similar compounds that only differ by a minor structural modification but exhibit a large difference in their binding affinity for a given target.ACs offer crucial... Activity cliffs(ACs)are generally defined as pairs of similar compounds that only differ by a minor structural modification but exhibit a large difference in their binding affinity for a given target.ACs offer crucial insights that aid medicinal chemists in optimizing molecular structures.Nonetheless,they also form a major source of prediction error in structure-activity relationship(SAR)models.To date,several studies have demonstrated that deep neural networks based on molecular images or graphs might need to be improved further in predicting the potency of ACs.In this paper,we integrated the triplet loss in face recognition with pre-training strategy to develop a prediction model ACtriplet,tailored for ACs.Through extensive comparison with multiple baseline models on 30 benchmark datasets,the results showed that ACtriplet was significantly better than those deep learning(DL)models without pretraining.In addition,we explored the effect of pre-training on data representation.Finally,the case study demonstrated that our model's interpretability module could explain the prediction results reasonably.In the dilemma that the amount of data could not be increased rapidly,this innovative framework would better make use of the existing data,which would propel the potential of DL in the early stage of drug discovery and optimization. 展开更多
关键词 Activity cliff Triplet loss Deep learning Pre-training
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Rayleigh-Bénard湍流热对流中主动和被动标量场Cliff结构统计特性的实验研究
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作者 周全 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第6期637-643,共7页
实验研究了Rayleigh-Bénard湍流热对流中主动和被动标量场Cliff结构的统计特性,实验参数Rayleigh数为Ra=1.2×1010,Prandtl数为Pr=5.3.在充满对流介质水的长方体对流槽边壁附近实验测量了局域浓度场(被动标量场)和局域温度场(... 实验研究了Rayleigh-Bénard湍流热对流中主动和被动标量场Cliff结构的统计特性,实验参数Rayleigh数为Ra=1.2×1010,Prandtl数为Pr=5.3.在充满对流介质水的长方体对流槽边壁附近实验测量了局域浓度场(被动标量场)和局域温度场(主动标量场)的时间序列,从测得的时间序列中提取出Cliff结构,提取参数为β,并分析了Cliff结构的宽度、振幅和尺寸的数量分布图.研究发现,浓度和温度场Cliff结构宽度的数量分布图形状并不随β而改变,而Cliff结构的最可几振幅却随着β的增大而增大.此外,Cliff结构的尺寸满足对数正态分布,这表明湍流热对流中被动标量场的扩散和混合是由羽流等浮力相干结构所驱动的. 展开更多
关键词 Rayleigh-Bénard 湍流热对流 标量湍流 主动标量 被动标量 Ramp-cliff结构
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The Cliff:A Deconstructive Analysis of The Catcher in the Rye
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作者 唐建南 《英语广场(学术研究)》 2012年第1期8-11,共4页
Just as the cliff serves as a demarcation between two different worlds, there seems to the protagonist in The Catcher in the Rye the dichotomies between innocence and corruption, children and adults. While these duali... Just as the cliff serves as a demarcation between two different worlds, there seems to the protagonist in The Catcher in the Rye the dichotomies between innocence and corruption, children and adults. While these dualisms are projected in the story, they are also deconstructed and the characterization of Holden clearly shows the instability of those dualisms. 展开更多
关键词 cliff DECONSTRUCTION DUALISM INNOCENCE CORRUPTION
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A model for calculating the erosion distance of soft sea cliff under wave loading 被引量:2
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作者 CHANG Fangqiang SHU Zhonglei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第7期69-77,共9页
A model for calculating the erosion distance of soft sea cliff under wave loading is established based on the erosion mechanism of soft sea cliff under wave loading and for considering wave hydrodynamic and sea cliff ... A model for calculating the erosion distance of soft sea cliff under wave loading is established based on the erosion mechanism of soft sea cliff under wave loading and for considering wave hydrodynamic and sea cliff material parameters.The model is verified,and the parameters are regressed using an indoor flume experiment.The erosion distances of the sea cliff in the northeast of the Pingtan Island are calculated by the model,and the results are compared with the measured data.The maximum erosion occurs in static water level,the location of the maximum erosion moves up as the wave continues,and the erosion stops when the wave lasts for a period of time.The erosion does not occur until the wave height exceeds a critical value; however,the contribution of large waves to the erosion is not relatively substantial.The calculated erosion distances at two places in the northeast of Pingtan Island are 0.32 m and 0.26 m. 展开更多
关键词 wave soft sea cliff EROSION
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A composite fall-slippage model for cliff recession in the sedimentary coastal cliffs 被引量:1
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作者 K.S.Sajinkumar J.P.Kannan +2 位作者 G.K.Indu C.Muraleedharan V.R.Rani 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第4期903-914,共12页
A composite fall-slippage model is proposed in this study for the Tertiary sedimentary coastal cliffs of Varkala in the western coastal tract of Peninsular India which are retreating landwards due to the combination o... A composite fall-slippage model is proposed in this study for the Tertiary sedimentary coastal cliffs of Varkala in the western coastal tract of Peninsular India which are retreating landwards due to the combination of several factors.The fall model in the present study accounts both spring seepage and wave action,resulting in undercutting and this fall affects only the topmost laterite and the just below sandstone in the cliff.Slippage in this area affects all the litho-units and hence the geologic characteristics of all the litho-units are considered for developing the slippage model.This mathematically derived model can be used in other cliffs exhibiting the same morphology as well as the one controlled by the same influencing factors.This model differs from other models in incorporating multi-lithounits as well as multi-notches.Varkala cliffs form a part of the aspiring geopark in the Global Geopark Network and hence a study on the cliff recession is a pressing requirement. 展开更多
关键词 Coastal cliff Coastal landslide cliff recession model Varkala
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分析电镜Cliff-Lorimer因子测量及薄标样标准化探讨
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作者 孙振亚 刘永康 《分析测试学报》 CAS CSCD 1999年第3期1-4,共4页
采用电子探针矿物标样,即均匀性和稳定性符合显微定量分析要求的国标样品,制备成适于分析电镜(AEM)成分分析的薄样品,测量了一组Clif-Lorimer(CL)因子,考察了用不同型号的分析电镜分析时CL因子的变化,提出... 采用电子探针矿物标样,即均匀性和稳定性符合显微定量分析要求的国标样品,制备成适于分析电镜(AEM)成分分析的薄样品,测量了一组Clif-Lorimer(CL)因子,考察了用不同型号的分析电镜分析时CL因子的变化,提出了仪器校正因子KI=εB/εA,对原子序数小于20的较轻元素其CL应考虑作KI校正;作者建议采用易于制成薄晶片的黑云母标样来统一不同分析条件下的CL因子,并应建立适于分析电镜定量分析的无机薄标样通用技术条件。 展开更多
关键词 K值 分析电镜 因子 薄标样 标准化 AEM CL因子
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The Environment Significance of Aerinite——First Discovered in the UBC Cliffs
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作者 WANG Guanyu WANG Hejing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第1期103-113,共11页
To analyze the composition and structure of the pale blue outcrop from the UBC Cliffs and research the environmental significance of aerinite recorded in the sediments, mineral composition, bulk chemical composition a... To analyze the composition and structure of the pale blue outcrop from the UBC Cliffs and research the environmental significance of aerinite recorded in the sediments, mineral composition, bulk chemical composition and structural analyses were carried out by means of X-ray diffraction(XRD), field emission scanning electron microscope(FESEM), transmission electron microscope(TEM), electron microprobe analysis(EMPA) and X-ray fluorescence spectra(XRF). Quartz, feldspar, mica, chlorite and aerinite as well as a small amount of amphibole, calcite, clinopyroxene, rutile, perovskite and apatite are recorded in the sediments. It is reported for the first time that the aerinite occurs in a high latitude area and in sediments paragenetic with mica and chlorite. The large span in grain size shows a typical characteristic of fluvioglacial sediments. Geochemistry characteristics(CIA, CIW, PIA, WIP and ICV) verify that there is virtually no chemical weathering. Mineralogy and geochemistry features of the UBC Cliffs sediments indicate that aerinite is accommodate to the high latitude and cold, dry climate. As the sediments show high similarity to those of their provenance, they have great significance in the identification of the forming condition and origin of the aerinite. 展开更多
关键词 UBC cliffS SEDIMENTS aerinite MUSCOVITE CHLORITE environment SIGNIFICANCE
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Integrated hazard assessment of rockfall incidents in the Cap Aokas Cliff Region
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作者 Zohra LADJEL Farid ZAHRI +3 位作者 Riheb HADJI Younes HAMED Karim ZIGHMI Kaddour BENMARCE 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1916-1929,共14页
Rock fall accidents in mountainous cliff areas have significant consequences for human life and transportation.This study aimed to evaluate the rockfall hazard in the Cap Aokas cliff region located along the northeast... Rock fall accidents in mountainous cliff areas have significant consequences for human life and transportation.This study aimed to evaluate the rockfall hazard in the Cap Aokas cliff region located along the northeast coast of Algeria by identifying the key factors contributing to rockfall occurrence.We employed a combination of kinematic analysis,Matterocking method,and 3D trajectory simulations to determine zones that are susceptible to rockfall mobilization.By using a probabilistic and structural approach in conjunction with photogrammetry,we identified the controlling factors.The kinematic analysis revealed the presence of five discontinuity families,which indicated both plane and wedge failure modes.The 3D trajectory simulations demonstrated that the falling blocks followed the stream direction.We then validated the susceptibility maps generated from the analysis using aerial photos and historical rockfall events.The findings of this study enhance our understanding of rockfall phenomena and provide valuable insights for the development of effective strategies to mitigate rockfall hazards. 展开更多
关键词 Trajectory simulations Probabilistic analysis Structural approach Rockfall hazard Cap Aokas cliff
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Cartography of Landslide Susceptibility around the Dias Horst and Thies Cliff-Senegal
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作者 Issa Ndoye Mapathé Ndiaye +2 位作者 Déthié Sarr Papa Sanou Faye Ibrahima Khalil Cissé 《International Journal of Geosciences》 2017年第6期821-836,共16页
The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and p... The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and passive factors. Passive factors regroup all the intrinsic conditions existing on the field at all times. The active factors or triggering factors are present sporadically and are added to the passive factors to trigger a landslide. With the weighted overlay method using ArcGIS?, four scenarios have been developed. A first scenario where only passive factors are combined and three scenarios for which we have for each scenario the passive factors combined with an active factor. With these different scenarios, five levels of susceptibility are obtained in the zone. These levels range from very low to very high susceptibility. For the different scenarios, the results show that the zone consists mainly of very low to low susceptibility with at least 61% of the area, followed by moderate susceptibility (23.54% to 38.24%) and last land with high susceptibility to very high with less than 1% of the surface. Fields with high to very high susceptibility are located on the slopes of the hills. Among the active factors, only the rainfall significantly modifies the percentage of land susceptible to landslide but remains in the field of moderate susceptibility. The predicted susceptibilities are closer to the observed landslides around the Thies Cliff than to the Dias Horst. 展开更多
关键词 CARTOGRAPHY SUSCEPTIBILITY LANDSLIDES Dias HORST Thies cliff
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Connotations of architectural culture transmitted in cliff carvings in the Bashu region
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作者 林从华 《Journal of Chongqing University》 CAS 2006年第3期181-186,共6页
Based on site studies, historical literature investigation and academic communication, this work aims to dig out the cultural significance in architectural and religious aspects conveyed in cliff carvings in the Bashu... Based on site studies, historical literature investigation and academic communication, this work aims to dig out the cultural significance in architectural and religious aspects conveyed in cliff carvings in the Bashu region. After casting a glance at the origin and evolution of Bashu culture and religion mainly involving Daoism and Buddhism recorded in forms of cliff carvings, we concentrated on discovering the national, regional and folk architectural characters implicated in cliff carvings at different sites within the Bashu region. The cliff carvings in this region vividly depicted the evolution of the architectural culture hereof. The essence of their religious and architectural connotations can be good stuff to be input in today’s architectural design philosophy. 展开更多
关键词 cliff carvings architectural culture Bashu DAOISM BUDDHISM
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Succession of the Plant Communities of the Ustyurt Eastern Cliff (Republic of Uzbekistan) in Connection with Climate Change
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作者 Adilov Bekhzod Rakhimova Tashkhonim +2 位作者 Shomurodov Khabibullo Rakhimova Nodira Vokhidov Yusuf 《Journal of Environmental Protection》 2018年第13期1408-1424,共17页
A decrease in the amount of precipitation is observed on average 18 - 20 mm compared with the periods before the Aral crisis and the average annual temperature rise over the long-term period is 2.0°C in the Centr... A decrease in the amount of precipitation is observed on average 18 - 20 mm compared with the periods before the Aral crisis and the average annual temperature rise over the long-term period is 2.0°C in the Central part of Ustyurt. An increase in the Si index meaning an increase in the degree of drought every ten-flight is clearly expressed in the months March-July. Data Analysis 1981-2017 shows that within 36 years the species diversity in the monitoring sites of Kabanbay decreased by 2 - 3 times. In 1981 the number of species fluctuated between the values of 9 - 50, and in 2017 this figure is 4 - 17. The results of the analysis show that the forecast indicators of the old-current state (1981) of the vegetation coverage and number of species were stable or had tendencies with a low regressive character (r2 = 0.01). However, the current-state (2017) of the vegetation coverage and the species composition of the monitoring plots showed a low progressive trend (r2 = 0.03), i.e. in the future, the formation of plant communities with low vegetation coverage and species composition has a dominant status. The results show that in 1981, 65% - 80% of the species composition of plant communities consisted of halophyte and xerophyte groups. In 2017, this figure reaches 80% - 100%, i.e. this claims to increase xerophytization and halophytization of territories. An interesting fact is established with mesophyte group. In general, theoretically, the decrease in the number of mesophyte group of plants for 1981-2017 would have a direct correlation with the vegetation coverage and their active share in it. However, for 36 years, their active share in the vegetation coverage remained unchanged—amounting to 0% - 20%. Of course, in these years, the decrease in the number of mesophyte plants led to an increase in the number of plant communities, in which the proportion of vegetation coverage of mesophyte group is insignificant—0% - 5%. Despite the drought, the active part of the vegetation cover of mesophytic invasive species, such as Poa bulbosa, is consistently maintained. 展开更多
关键词 Ustyurt Plateau EASTERN cliff Climate Change SPECIES Diversity Total PROJECTIVE Cover Invasive SPECIES
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Geomechanical Characterization of Sandstones Cliffs of Segou (Senegal, West Africa) in the Madina Kouta Basin
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作者 Déthié Sarr Meissa Fall +3 位作者 Papa Malick Ngom Mapathé Ndiaye Cheikh H. Kane Makhaly Ba 《International Journal of Geosciences》 2012年第1期166-174,共9页
This work presents the behavior of Segou sandstones in the laboratory and in the field conditions. Four types of sandstone are collected in the northern part of the Madina Kouta basin (eastern Senegal). These types of... This work presents the behavior of Segou sandstones in the laboratory and in the field conditions. Four types of sandstone are collected in the northern part of the Madina Kouta basin (eastern Senegal). These types of specimens are the white sandstones, the red sandstones, the purple sandstones and the sandstones with intercalation of pelites. Uniaxial tests are carried out on these specimens of sandstones. The Young Moduli (E) and the Uniaxial Compression Strengths (Rc) are higher for the white sandstone. Values of the mechanical parameters decrease slightly for red sandstones due to an increase of the amount of pelites in the composition of the rock. Decrease of mechanical parameters is more important for the purple facies due to an important network of fractures. The facies with weaker characteristics corresponds to the sandstones with intercalation of pelites. This is due to the soft nature of the pelites. The slope stability of the Cliff sides depends also on to these characteristics. 展开更多
关键词 Unconfined Compression Test-Uniaxial Compression Strength (UCT Rc) JRC (Joint ROUGHNESS Coefficient) Young Modulus (E) ROUGHNESS Segou-Madina Kouta BASIN Discontinuities Dihedral Slope cliff
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Investigation on Distribution Status and Research on Historical Value of Cliff Stone Carving Ancient Sites in Liaoning Province
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作者 CHENYifeng 《外文科技期刊数据库(文摘版)自然科学》 2022年第6期051-054,共4页
Cliff stone carvings are drawn from the calligraphic art of literati in various periods. Other types include statues and rock paintings. When art and nature are mixed together, they will present a more detached aesthe... Cliff stone carvings are drawn from the calligraphic art of literati in various periods. Other types include statues and rock paintings. When art and nature are mixed together, they will present a more detached aesthetic interest. The imposing manner of these stone monuments is very grand. In addition, the running script, official script, cursive script and seal script have their own artistic flavor, which adds to the value of historical research. Based on this, this paper analyzes the distribution of the cliff-carved stone ancient ruins in Liaoning area, and further discusses and studies the historical research value of this site for the reference of relevant practitioners. 展开更多
关键词 cliff stone carving site distribution status of the site historical value
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苏轼诗词英译和英语世界普通读者接受研究——以《念奴娇·赤壁怀古》的英译本为例
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作者 李瑶 许士楠 《西南科技大学学报(哲学社会科学版)》 2026年第1期123-132,共10页
苏轼诗词构思精巧、语言精练、意蕴无穷,是向英语世界传播中华优秀古典诗词的绝佳载体之一。本研究基于接受理论,比较许渊冲、王红公、戴维·亨顿的《念奴娇·赤壁怀古》译文呈现效果,结合普通英语读者评价,探究译文呈现效果与... 苏轼诗词构思精巧、语言精练、意蕴无穷,是向英语世界传播中华优秀古典诗词的绝佳载体之一。本研究基于接受理论,比较许渊冲、王红公、戴维·亨顿的《念奴娇·赤壁怀古》译文呈现效果,结合普通英语读者评价,探究译文呈现效果与译本接受程度之间的差异。研究发现,苏轼诗词在普通英语读者中的接受程度主要受译文语言特征与内副文本的影响。译介底蕴深厚的苏轼诗词应始终保有读者考量,预测目标群体的审美经验与潜在期待,在保留原文文化特质的同时,尽量贴合受众的语言习惯。同时,借助内副文本等手段拉近读者与作者及作品的距离,及时跟进读者反馈并适时做出必要调整,逐渐增强以苏轼诗词为代表的中国古典诗词在英语世界里的文化传播。 展开更多
关键词 苏轼诗词 《念奴娇·赤壁怀古》 普通读者 接受
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基于参数优化WOA-VMD-MCKD在强背景噪声下的轴承故障诊断
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作者 薛怀恒 买买提热依木·阿布力孜 +2 位作者 吴许坤 阿合朱力·吾木尔吾扎克 姚俊慧 《科学技术与工程》 北大核心 2026年第2期607-622,共16页
针对滚动轴承早期故障特征易受强背景噪声影响而难以提取的问题,提出了一种基于鲸鱼优化算法优化变分模态分解(variational mode decomposition,VMD)和相关最大峭度解卷积(maximum correlated kurtosis deconvolution,MCKD)参数的滚动... 针对滚动轴承早期故障特征易受强背景噪声影响而难以提取的问题,提出了一种基于鲸鱼优化算法优化变分模态分解(variational mode decomposition,VMD)和相关最大峭度解卷积(maximum correlated kurtosis deconvolution,MCKD)参数的滚动轴承故障诊断方法。首先,利用鲸鱼优化算法并选取包络熵最小值作为目标函数优化VMD算法中分解层数K和惩罚因子α,得到VMD分解结果,并基于加权相关峭度选取最优分量进行重构;其次,依据重构分量的包络谱图算得MCKD算法的T值,利用鲸鱼优化算法(whale optimization algorithm,WOA)并选取加权包络谱峭度最大值作为目标函数优化MCKD算法中滤波器长度L和位移数M,并将重构信号通过MCKD算法增强重构分量中的冲击成分;最后,通过包络谱分析判断滚动轴承故障类型。仿真分析与试验测试的结果均显示,该方法具备从故障信号中有效提取并显著增强冲击成分的能力,可以清楚地看到故障频率的多倍频。即便在强背景噪声干扰的情况下,该方法仍能够成功实现对滚动轴承早期故障的精准诊断。 展开更多
关键词 故障诊断 滚动轴承 鲸鱼优化算法 变分模态分解 最大相关峭度解卷积
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Cliffs Notes丛书介绍
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作者 郁文 《外语界》 1983年第2期28-31,共4页
上海外国语学院图书馆去年从美国引进一套对教学工作者有相当参考作用的外国文学作品丛书——Cliffs Notes。这套丛书包括外国古今文学作品二百多本,系美国内布拉斯加州林肯城Cliffs Notes出版社发行。经初步浏览,并参照其前言介绍,这... 上海外国语学院图书馆去年从美国引进一套对教学工作者有相当参考作用的外国文学作品丛书——Cliffs Notes。这套丛书包括外国古今文学作品二百多本,系美国内布拉斯加州林肯城Cliffs Notes出版社发行。经初步浏览,并参照其前言介绍,这套丛书的作者都是研究文学作品的专家,或者是一些较长时期从事文学教学、有相当经验的教师。作者和出版部门旨在为文学作品的学习者在研究、学习某一作品时提供某些启示,但并不强求读者无条件地接受其注解的观点,而是希望能在阅读中得出自己的结论。作者深知在文学作品的研究中。 展开更多
关键词 丛书 汇刻书 cliffs Notes
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公路隧道悬崖洞口进洞方法的比较分析
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作者 黄立宇 杨弄平 孙汝 《云南水力发电》 2026年第2期32-36,共5页
以大永高速某隧道出口端进洞施工为实例,介绍了在洞口段围岩破碎岩性较差、陡峭崖壁、难以修建施工便道等条件下,提出了修建施工支洞进洞的施工技术及工艺,相较于传统公路隧道悬崖洞口回填进洞施工方法,减少了对周边生态环境破坏,可达... 以大永高速某隧道出口端进洞施工为实例,介绍了在洞口段围岩破碎岩性较差、陡峭崖壁、难以修建施工便道等条件下,提出了修建施工支洞进洞的施工技术及工艺,相较于传统公路隧道悬崖洞口回填进洞施工方法,减少了对周边生态环境破坏,可达到缩短工期的效果,并有效保障了施工安全。 展开更多
关键词 公路隧道 陡峭崖壁 施工支洞 施工技术
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Scaling Development Cliffs--Victory in the anti-poverty battle of a cliff-top village gives hope for other impoverished places
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作者 Wang Hairong 《Beijing Review》 2020年第21期34-35,共2页
White puffy clouds drift past a bungalow facing a deep valley and a towering peak beyond it.Chirps of birds animate the idyllic scene without shattering its serenity.The bungalow with a wood-plank roof and mud walls i... White puffy clouds drift past a bungalow facing a deep valley and a towering peak beyond it.Chirps of birds animate the idyllic scene without shattering its serenity.The bungalow with a wood-plank roof and mud walls is featured in a video clip that Mouse Labo posted online on April 13. 展开更多
关键词 SCALING DEVELOPMENT cliffS
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岩画与神话视野下的“采药昆仑”石刻 被引量:2
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作者 汤惠生 《广西师范大学学报(哲学社会科学版)》 2025年第5期176-184,共9页
对于近期在青海河源地区发现的“采药昆仑”石刻,我们应该严格地按照考古遗址来对待,其研究应分做考古学遗址研究和文本研究两个部分。考古学遗址研究是一种更倾向于自然科学的研究,涉及遗址的生成(文字的刻凿)、侵蚀的方式、石锈的形... 对于近期在青海河源地区发现的“采药昆仑”石刻,我们应该严格地按照考古遗址来对待,其研究应分做考古学遗址研究和文本研究两个部分。考古学遗址研究是一种更倾向于自然科学的研究,涉及遗址的生成(文字的刻凿)、侵蚀的方式、石锈的形成、微腐蚀测年等问题。文本研究则是人文研究,主要是文献的对比与考证,涉及“远游”、“不死药”、马车、勒石以纪等问题。根据对遗址本体和文本两个方面的分析,可以确定“采药昆仑”石刻是一处极为重要的秦代石刻遗址,它揭示出诸多前所未知的历史信息,并且证实或改变了我们对历史的某些固有认识。 展开更多
关键词 “采药昆仑”石刻 微腐蚀测年 石锈 穆天子传 登仙
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Scaffold and SAR studies on c-MET inhibitors using machine learning approaches 被引量:1
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作者 Jing Zhang Mingming Zhang +10 位作者 Weiran Huang Changjie Liang Wei Xu Jinghua Zhang Jun Tu Innocent Okohi Agida Jinke Cheng Dong-Qing Wei Buyong Ma Yanjing Wang Hongsheng Tan 《Journal of Pharmaceutical Analysis》 2025年第6期1321-1333,共13页
Numerous c-mesenchymal-epithelial transition(c-MET)inhibitors have been reported as potential anticancer agents.However,most fail to enter clinical trials owing to poor efficacy or drug resistance.To date,the scaffold... Numerous c-mesenchymal-epithelial transition(c-MET)inhibitors have been reported as potential anticancer agents.However,most fail to enter clinical trials owing to poor efficacy or drug resistance.To date,the scaffold-based chemical space of small-molecule c-MET inhibitors has not been analyzed.In this study,we constructed the largest c-MET dataset,which included 2,278 molecules with different struc-tures,by inhibiting the half maximal inhibitory concentration(IC_(50))of kinase activity.No significant differences in drug-like properties were observed between active molecules(1,228)and inactive mol-ecules(1,050),including chemical space coverage,physicochemical properties,and absorption,distri-bution,metabolism,excretion,and toxicity(ADMET)profiles.The higher chemical diversity of the active molecules was downscaled using t-distributed stochastic neighbor embedding(t-SNE)high-dimensional data.Further clustering and chemical space networks(CSNs)analyses revealed commonly used scaffolds for c-MET inhibitors,such as M5,M7,and M8.Activity cliffs and structural alerts were used to reveal“dead ends”and“safe bets”for c-MET,as well as dominant structural fragments consisting of pyr-idazinones,triazoles,and pyrazines.Finally,the decision tree model precisely indicated the key structural features required to constitute active c-MET inhibitor molecules,including at least three aromatic het-erocycles,five aromatic nitrogen atoms,and eight nitrogeneoxygen atoms.Overall,our analyses revealed potential structure-activity relationship(SAR)patterns for c-MET inhibitors,which can inform the screening of new compounds and guide future optimization efforts. 展开更多
关键词 c-MET inhibitors Machine learning Structure-activity relationship Hierarchical clustering Scaffold based chemical space Active cliff
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