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Data-enhanced revealing of trends in Geoscience 被引量:1
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作者 Yu Zhao Meng Wang +6 位作者 Jiaxin Ding Jiexing Qi Lyuwen Wu Sibo Zhang Luoyi Fu Xinbing Wang Li Cheng 《Journal of Data and Information Science》 CSCD 2024年第3期29-43,共15页
Purpose:This article presents an in-depth analysis of global research trends in Geosciences from 2014 to 2023.By integrating bibliometric analysis with expert insights from the Deep-time Digital Earth(DDE)initiative,t... Purpose:This article presents an in-depth analysis of global research trends in Geosciences from 2014 to 2023.By integrating bibliometric analysis with expert insights from the Deep-time Digital Earth(DDE)initiative,this article identifies key emerging themes shaping the landscape of Earth Sciences①.Design/methodology/approach:The identification process involved a meticulous analysis of over 400,000 papers from 466 Geosciences journals and approximately 5,800 papers from 93 interdisciplinary journals sourced from the Web of Science and Dimensions database.To map relationships between articles,citation networks were constructed,and spectral clustering algorithms were then employed to identify groups of related research,resulting in 407 clusters.Relevant research terms were extracted using the Log-Likelihood Ratio(LLR)algorithm,followed by statistical analyses on the volume of papers,average publication year,and average citation count within each cluster.Additionally,expert knowledge from DDE Scientific Committee was utilized to select top 30 trends based on their representation,relevance,and impact within Geosciences,and finalize naming of these top trends with consideration of the content and implications of the associated research.This comprehensive approach in systematically delineating and characterizing the trends in a way which is understandable to geoscientists.Findings:Thirty significant trends were identified in the field of Geosciences,spanning five domains:deep space,deep time,deep Earth,habitable Earth,and big data.These topics reflect the latest trends and advancements in Geosciences and have the potential to address real-world problems that are closely related to society,science,and technology.Research limitations:The analyzed data of this study only contain those were included in the Web of Science.Practical implications:This study will strongly support the organizations and individual scientists to understand the modern frontier of earth science,especially on solid earth.The organizations such as the surveys or natural science fund could map out areas for future exploration and analyze the hot topics reference to this study.Originality/value:This paper integrates bibliometric analysis with expert insights to highlight the most significant trends on earth science and reach the individual scientist and public by global voting. 展开更多
关键词 GEOSCIENCES Research trends BIBLIOMETRICS Expert knowledge Global voting
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Analysis of the spatiotemporal trends and influencing factors of Hyphantria cunea in China
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作者 Hongwei Zhou Chaoqun Gong +2 位作者 Xiaodong Li Yue Wang Yunbo Yan 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期294-305,共12页
In recent years,the situation of the Hyphantria cunea(Drury)(Lepidoptera:Erebidae),infestation in China has been serious and has a tendency to continue to spread.A comprehensive analysis was carried out to examine the... In recent years,the situation of the Hyphantria cunea(Drury)(Lepidoptera:Erebidae),infestation in China has been serious and has a tendency to continue to spread.A comprehensive analysis was carried out to examine the spa-tial distribution trends and influencing factors of H.cunea.This analysis involved integrating administrative division and boundary data,distribution data of H.cunea,and envi-ronmental variables for 2021.GeoDetector and gravity analysis techniques were employed for data processing and interpretation.The results show that H.cunea exhibited high aggregation patterns in 2021 and 2022 concentrated mainly in eastern China.During these years,the focal point of the infestation was in Shandong Province with a spread towards the northeast.Conditions such as high vegetation density in eastern China provided favorable situations for growth and development of H.cunea.In China,the spatial distribution of the moth is primarily influenced by two critical factors:precipitation during the driest month and elevation.These play a pivotal role in determining the spread of the species.Based on these results,suggestions are provided for a mul-tifaceted approach to prevention and control of H.cunea infestation. 展开更多
关键词 Hyphantria cunea Temporal trends GeoDetector spatial analysis Spatial heterogeneity
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Production and trade trend of oils and oilseeds in BRICS countries
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作者 ZHANG Hong 《中国油脂》 CAS CSCD 北大核心 2024年第8期1-10,共10页
In order to promote agricultural production and trade cooperation among BRICS countries,and ensure the security and stability of the oils and oilseeds industrial and supply chains in China and the world,the production... In order to promote agricultural production and trade cooperation among BRICS countries,and ensure the security and stability of the oils and oilseeds industrial and supply chains in China and the world,the production,consumption,trade trend,and cooperation potential of oils and oilseeds in BRICS countries were expounded,and relevant policy recommendations were put forward.Most of the BRICS countries are major agricultural producers,and they are also important agricultural product consumption markets in the world.In 2023/2024,the production and consumption of oilseeds in BRICS countries account for nearly half of the world's total;the production of vegetable oils exceeds a quarter of the world's total,and the consumption of vegetable oils accounts for 40%of the world's total.In 2023/2024,the import and export volume of oilseeds exceeds half of the world's total;vegetable oil imports account for 40%of the world's total,and exports account for about one tenth of the world's total.China's imports of oilseeds and oils from BRICS countries account for 68%and 29%of its global imports in 2023,respectively.BRICS countries are rich in agricultural land resources,have great potential for oils and oilseeds production,obvious complementary advantages in trade structure,and huge space for future cooperation.It is suggested that Brazil should be included in the"Belt and Road"co-construction category to promote the continuous deepening of agricultural cooperation between China and Brazil.It is suggested to explore regional agricultural trade agreements among BRICS countries,promote currency settlement and exchange among BRICS countries,and enhance the facilitation and stability of BRICS trade.It is suggested that China should increase its investment in BRICS countries and export advanced technology and management experience to benefit local agricultural development and achieve a mutually beneficial and win-win situation. 展开更多
关键词 BRICS countries oils and oilseeds production and consumption trade trend agricultural potential
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Tomorrow's Textiles: 2024 Fabric trends to know
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《China Textile》 2024年第1期52-53,共2页
Looking ahead to 2024,the textile industry is poised for exciting developments as sustainable innovation,diverse color palettes,and a fusion of luxury and comfort take center stage.In this article,we delve into the up... Looking ahead to 2024,the textile industry is poised for exciting developments as sustainable innovation,diverse color palettes,and a fusion of luxury and comfort take center stage.In this article,we delve into the upcoming fabric trends,offering a roadmap for navigating the evolving fabric landscape.From eco-conscious materials to global design influences,we explore the trends that will shape creative projects with style and responsibility. 展开更多
关键词 offering TEXTILES trendS
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Blokecore:The trend of jersey wearing
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作者 Zhong Mengxia 《China Textile》 2024年第4期62-63,共2页
The 2024 Olympics in Paris kicked off on28 July.Fashion and sports are closer than ever.In fact,"Blokecore"has become a major fashion trend.What is Blokecore?Blokecore is a style of dressing inspired by the ... The 2024 Olympics in Paris kicked off on28 July.Fashion and sports are closer than ever.In fact,"Blokecore"has become a major fashion trend.What is Blokecore?Blokecore is a style of dressing inspired by the British pub culture of the 80s and 90s,which emphasizes a masculine male image,expressing love and support for soccer culture by wearing sa soccer jersey,jeans and sneake rs.This style is not only limited to soccer fans,but has also gradually walked into the daily lives of fashionistas,becoming a unique trend. 展开更多
关键词 CULTURE trend CLOSER
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On the correlation of nonlinear variables containing secular trend variations: numerical experiments 被引量:6
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作者 施能 易燕明 +1 位作者 顾骏强 夏冬冬 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第9期2180-2184,共5页
Due to global warming, the general circulation, underlying surfaces characteristics, and geophysical and meteorological elements all show evident secular trends. This paper points out that when calculating the correla... Due to global warming, the general circulation, underlying surfaces characteristics, and geophysical and meteorological elements all show evident secular trends. This paper points out that when calculating the correlation of two variables containing their own obvious secular trends, the interannual correlation characteristics between the two variables may be distorted (overestimated or underestimated). Numerical experiments in this paper show that if two variables have opposite secular trends, the correlation coefficient between the two variables is reduced (the positive correlation is underestimated, or the negative correlation is overestimated); and if the two variables have the same sign of secular trends, the correlation coefficient between the two variables is increased (the positive correlation is overestimated, or the negative correlation is underestimated). Numerical experiments also suggest that the effect of secular trends on the interannual correlation of the two variables is interchangeable, that is to say, as long as the values of the two trends are not changed, the two variables interchange their positions, and the effect of the secular trends on the interannual correlation coefficient of the two variables remains the same. If the two variables have the same-(opposite-) sign trends, the effect of secular trends on the interannal correlation coefficient is more (less) distinctive. A meteorological example is given. 展开更多
关键词 correlation analysis secular trend trend coefficient numerical experiment
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A Study on the Ideographic Trend of Chinese Loan Words in Translation
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作者 臧国宝 普映山 《海外英语》 2011年第6X期7-8,共2页
Based on the redefinition of Chinese loan words and corresponding types of Chinese loan words, this article makes an initiative hypothesis that nowadays the ideographic trend of Chinese loan words is being hastened to... Based on the redefinition of Chinese loan words and corresponding types of Chinese loan words, this article makes an initiative hypothesis that nowadays the ideographic trend of Chinese loan words is being hastened to a greater degree than before.Depending on the Prototype Models Theory for the types of Chinese loan words, a comprehensive analysis of this trend is made in four aspects:the transfer from transliteration loans to loan translation;the ideographic trend of transliteration loans;the full ideograph of shift loan words;word-for-word translation of loan words. 展开更多
关键词 Chinese LOAN WORDS types of LOAN WORDS IDEOGRAPHIC trend
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Trends in mortality of emergency departments patients in China 被引量:11
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作者 Chang Pan Xiao-ran Huang +3 位作者 Jiao-jiao Pang Kai Cheng Feng Xu Yu-guo Chen 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2019年第3期152-155,共4页
BACKGROUND: Emergency medical service system (EMSS) in China is becoming more important. However, studies on mortality of emergency departments (EDs) patients in tertiary hospitals and on the trends in mortality of ED... BACKGROUND: Emergency medical service system (EMSS) in China is becoming more important. However, studies on mortality of emergency departments (EDs) patients in tertiary hospitals and on the trends in mortality of ED patients all over China are stagnant. The objective of this study was to quantify and describe the trends in mortality of ED patients in China. METHODS: Nine tertiary teaching hospitals were selected from tertiary teaching hospitals in different regions. The annual numbers of ED visits and deaths of these hospitals in 2004, 2009 and 2014 were recorded and analyzed. Chi-square test was used to compare the mortality of the EDs’ visits. Moreover, data on the mortality of ED patients in China from 2005 to 2015 were summarized and analyzed from the China Health and Family Planning Statistical Yearbooks (2006–2016). RESULTS: From 2004 to 2014, the overall annual mortalities in EDs increased among the tertiary hospitals (P<0.001). However, the overall annual mortality in EDs all over China decreased from 0.12% in 2005 to 0.08% in 2015. And the mortalities of EDs patients in the eastern, central and western regions of China all decreased. In addition, the average mortality of EDs patients in northern China was obviously higher than that in southern China (P<0.05). CONCLUSION: The ED mortality was increased in tertiary hospitals while decreased all over China during the past decade, which may be partly caused by some critical challenges faced by China’s EMSS, such as overcrowding and long length of stay in EDs of tertiary hospitals. 展开更多
关键词 MORTALITY EMERGENCY departments TERTIARY hospitals trendS
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State of research and trends in development of wood adhesives 被引量:8
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作者 ZHAO Lei-feng LIU Yu XU Zheng-dong ZHANG Ya-zhuo ZHAO Fang ZHANG Shuang-bao 《Forestry Studies in China》 CAS 2011年第4期321-326,共6页
We aim to present an overview of the status of adhesives in the wood industry, especially in the area of wood-based panels. The review summarizes the current state of research of two kinds of adhesives, i.e., syntheti... We aim to present an overview of the status of adhesives in the wood industry, especially in the area of wood-based panels. The review summarizes the current state of research of two kinds of adhesives, i.e., synthetic adhesives and natural adhesives. Synthetic adhesives, consisting of urea-formaldehyde resins (UF), phenol-formaldehyde resins (PF), polyvinyl acetate emulsion (PVAc) and isocyanates, are widely used. For UF, most investigations are concerned with the reduction of free formaldehyde; for PF, most studies focus on finding new chemicals to replace phenol. PVAc has poor properties, but these can be improved by a blending reactions and copolymerization with other chemicals. Isocyanate is an environmentally friendly synthetic adhesive, but also suffers from inadequate properties. Natural adhesives, such as protein/starch, lignin and tannins, have poor bonding effect that limits their level of use, but their main advantages are that they are environmentally friendly and a renewable resource. Studies of modification can improve the bonding performances and gradually cause natural adhesives to become applied in industrial production. Some proposals for future development and the importance of environmentally friendly adhesives are provided, which will be helpful in future theoretical and experimental research. 展开更多
关键词 synthetic adhesives natural adhesives main features development trend
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Age trends and correlations of growth and wood properties in clone of Eucalyptus urophylla × E. grandis in Guangdong, China 被引量:3
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作者 WU Shi-jun XU Jian-min +3 位作者 LI Guang-you Du Zhi-hu LU Zhao-hua LI Bao-qi 《Journal of Forestry Research》 CAS CSCD 2012年第3期467-472,共6页
We assessed growth traits and wood properties ofDH32-29, a clone of Eucalyptus urophylla x E. grandis, at age of two to six years in Guangdong in China. Analysis of variance of studied traits showed that there were si... We assessed growth traits and wood properties ofDH32-29, a clone of Eucalyptus urophylla x E. grandis, at age of two to six years in Guangdong in China. Analysis of variance of studied traits showed that there were significant differences (1% level) on all studied traits among ages except for wood basic density. Analysis of age trends of growth traits and wood properties revealed that rotation length of DH32-29 should be more than six years or longer. Phenotypic correlations among traits at individual ages indicated that correlations between growth traits were strongly positive. There was significant change in relationship between growth and wood basic density with increasing age, ranging from -0.03 to -0.54 at 2 and 5 year and 0.003 to 0.3 at 3, 4 and 6 year. Correlations between Pilodyn pin penetration and basic density measured on increment cores showed that Pilodyn could rank or group genotypes or sites into density classes, but failure to predict individual tree and individual clone. 展开更多
关键词 EUCALYPT age trends growth traits wood properties CORRELATION nondestructive methods
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The history, hotspots, and trends of electrocardiogram 被引量:4
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作者 Xiang-Lin YANG Guo-Zhen LIU +7 位作者 Yun-Hai TONG Hong YAN Zhi XU Qi CHEN Xiang LIU Hong-Hao ZHANG Hong-Bo WANG Shao-Hua TAN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2015年第4期448-456,共9页
The electrocardiogram (ECG) has broad applications in clinical diagnosis and prognosis of cardiovascular disease. Many researchers have contributed to its progressive development. To commemorate those pioneers, and ... The electrocardiogram (ECG) has broad applications in clinical diagnosis and prognosis of cardiovascular disease. Many researchers have contributed to its progressive development. To commemorate those pioneers, and to better study and promote the use of ECG, we reviewed and present here a systematic introduction about the history, hotspots, and trends of ECG. In the historical part, information including the invention, improvement, and extensive applications of ECG, such as in long QT syndrome (LQTS), angina, and myocardial infarction (MI), are chronologi- cally presented. New technologies and applications from the 1990s are also introduced. In the second part, we use the bibliometric analysis me- thod to analyze the hotspots in the field of ECG-related research. By using total citations and year-specific total citations as our main criteria, four key hotspots in ECG-related research were identified from 11 articles, including atrial fibrillation, LQTS, angina and MI, and heart rate variability. Recent studies in those four areas are also reported. In the final part, we discuss the future trends concerning ECG-related research. The authors believe that improvement of the ECG instrumentation, big data mining for ECG, and the accuracy of diagnosis and application will be areas of continuous concern. 展开更多
关键词 ELECTROCARDIOGRAM HISTORY HOTSPOTS REVIEW trendS
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Introduction to Urban and Community Forestry in the United States of America: History, Accomplishments, Issues and Trends 被引量:3
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作者 Qi Yadong Zhang Zhiqiang 《Forestry Studies in China》 CAS 2003年第4期54-61,共8页
The urban and community forestry movement in the United States has matured over the last 20 years from managing street trees, to understanding the benefits of trees in urban ecosystems, and now to managing urban green... The urban and community forestry movement in the United States has matured over the last 20 years from managing street trees, to understanding the benefits of trees in urban ecosystems, and now to managing urban green infrastructure. This paper introduced the history, development, and major accomplishments of the urban and community forestry movement, highlighted the economic, ecological, environmental, and social values of forests and trees to communities, and discussed issues and trends of the urban and community forestry program in the United States. 展开更多
关键词 urban and community forestry urban forest benefits and values HISTORY accomplishments ISSUES trends United States
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Demographic trends and climate over 35 years in the Barro Colorado 50 ha plot 被引量:3
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作者 Richard Condit Rolando Pérez +2 位作者 Suzanne Lao Salomón Aguilar Stephen P. Hubbell 《Forest Ecosystems》 SCIE CSCD 2017年第4期273-285,共13页
Background: The first three censuses of the 50-ha plot at Barro Colorado Island spanned an unusually harsh dry season during the 1983 El Nitro. By the early 1990s, we had documented increases in tree mortality, tree ... Background: The first three censuses of the 50-ha plot at Barro Colorado Island spanned an unusually harsh dry season during the 1983 El Nitro. By the early 1990s, we had documented increases in tree mortality, tree growth, and large population fluctuations of many species during the 1982-1985 census interval. At the time, we asserted that increasing drought frequency would greatly affect the forest. With the benefit of five more censuses at Barro Colorado from 1995-2015, we can now put the 1980 conditions in a longer perspective and test the hypothesis that increasing droughtiness has continued to change the forest. Methods: A 50-ha forest plot on Barro Colorado Island was censused eight times, in 1982 and every five years since 1985. All free-standing woody stems were measured, mapped, and identified in each census. Results: 1) The period 1982-1992 included several extreme dry seasons, not just 1983, but since then there have been few such droughts. 2) Dbh growth declined from a peak in the early 1980s to its lowest in the early 1990s. From 1995-2015 it increased slightly, but not returning to the initial peak. Nearly every species and all dbh categories followed the same pattern. 3) The elevated stand-wide mortality rate of large trees during the 1982-1985 drought has not returned, and most individual species showed the same pattern of elevated mortality in the 1980s followed by low and fairly stable mortality after 1990. 4) Sapling mortality declined after 198,5, but rose again in the late-90s, so the 1980s drought period no longer looks unusual. Mortality of individual species' saplings fluctuated erratically, including cases where mortality during the drought was lower than after. 5) Population sizes of individual species fluctuated in all possible directions. Some species declined precipitously during the drought, then recovered, but others did not recover. Other species increased in abundance during the drought. Conclusions" Droughts of the 1980s elevated tree growth and mortality at Barro Colorado, but since 1990, demographic rates have remained lower, paralleling a moderate climate with few severe droughts after 1990. Moisture-demanding species suffered during the drought, but many have since recovered. We do not know how often such drought periods recur. Moreover, many species' abundances fluctuated over 35 years with no known cause. 展开更多
关键词 Demographic trends CLIMATE
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Analysis of the trend of global power sources based on comment emotion mining 被引量:3
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作者 Shengxiang Zhang Chao Shi +2 位作者 Xin Jiang Ying Zhang Lu Zhang 《Global Energy Interconnection》 2020年第3期283-291,共9页
In recent years,renewable energy technologies have been developed vigorously,and related supporting policies have been issued.The developmental trend of different energy sources directly affects the future development... In recent years,renewable energy technologies have been developed vigorously,and related supporting policies have been issued.The developmental trend of different energy sources directly affects the future developmental pattern of the energy and power industry.Energy trend research can be quantified through data statistics and model calculations;however,parameter settings and optimization are difficult,and the analysis results sometimes do not reflect objective reality.This paper proposes an energy and power information analysis method based on emotion mining.This method collects energy commentary news and literature reports from many authoritative media around the world and builds a convolutional neural network model and a text analysis model for topic classification and positive/negative emotion evaluation,which helps obtain text evaluation matrixes for all collected texts.Finally,a long-short-term memory model algorithm is employed to predict the future development prospects and market trends for various types of energy based on the analyzed emotions in different time spans.Experimental results indicate that energy trend analysis based on this method is consistent with the real scenario,has good applicability,and can provide a useful reference for the development of energy and power resources and of other industry areas as well. 展开更多
关键词 Global energy and power trend Topic classification Text emotion analysis CNN LSTM
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Vertical grain-size trend of mouth bar in lacustrine fan delta:Flume experiments 被引量:1
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作者 Ke Zhang Sheng-He Wu +3 位作者 Jun-Jie Wang Yun-Jie Xu Zhen-Hua Xu Jia-Jia Zhang 《Petroleum Science》 SCIE CAS CSCD 2022年第5期1964-1977,共14页
Field observational previously indicated a mouth bar of a fan delta could exhibit a fining-or coarseningupward trend,which bring a new challenge to the identification of mouth bar in subsurface studies due to the lack... Field observational previously indicated a mouth bar of a fan delta could exhibit a fining-or coarseningupward trend,which bring a new challenge to the identification of mouth bar in subsurface studies due to the lack of morphological descriptions.Previous studies have indicated that effluent behavior in rivermouth system can affect the vertical grain-size trend of mouth bar,but the drivers and magnitude of this phenomenon are not understood.We conducted flume experiments to investigate the mechanism and controlling factors of vertical grain-size trend of mouth bar.Experiment with a steeper slope of the substrate layer,greater discharge,higher sediment/water ratio,and coarser sediment induced a finingupward trend of mouth bar,because the effluent was dominated by strong inertia.Mouth bar in the experiment with a gentler slope of the substrate layer,smaller discharge,lower sediment/water ratio,and finer sediment exhibited a coarsening-upward trend dominated by the friction-dominated effluent.The relationship between the vertical grain-size trend of mouth bar and the gradients of foreset bedding in small-scale flume models and the cut-off of 15°-18°are applicable in natural systems.Identifying depositional setting to infer depositional process in river-mouth system and analyzing the plane geometry of sandbodies are two steps in the interpretation of ancient fan deltaic rock record. 展开更多
关键词 Mouth bar Vertical grain-size trend Effluent behavior INERTIA Bed friction
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Image texture indices and trend analysis for forest disturbance assessment under wood harvest regimes 被引量:1
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作者 Abdolrassoul Salmanmahiny Malihe Erfani +1 位作者 Afshin Danehkar Vahid Etemad 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第2期579-587,共9页
Effective disturbance indices for Hyrcanian forests in Kheyroud,Nowshahr,Iran were determined.The study area was divided into landscape mosaics based on ecosystem parameters including profile type,slope and elevation.... Effective disturbance indices for Hyrcanian forests in Kheyroud,Nowshahr,Iran were determined.The study area was divided into landscape mosaics based on ecosystem parameters including profile type,slope and elevation.Co-occurrence texture indices were derived as forest disturbance factors on the first five bands of Landsat TM,ETM+and OLI images for the prevailing wood harvest disturbance regimes.These indices were screened using ten types of trend analyses and used for modeling disturbance of the harvesting regime through artificial neural networks.The results show that the selected indices can be useful in distinguishing areas with different disturbance intensities and as such,used in the context of health assessment through the health distance method.The accuracy of the health maps derived from the indices[increasing disturbance]led to give rise higher disturbance classification accuracy. 展开更多
关键词 Ecosystem health DISTURBANCE trend analysis Co-occurrence texture indices Landscape mosaics
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Phonon Confinement Effect in Two-dimensional Nanocrystallites of Monolayer MoS_2 to Probe Phonon Dispersion Trends Away from Brillouin-Zone Center 被引量:1
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作者 石薇 张昕 +4 位作者 李晓莉 乔晓粉 吴江滨 张俊 谭平恒 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期111-114,共4页
The fundamental momentum conservation requirement q - 0 for the Raman process is relaxed in the nanocrystal- lites (NCs), and phonons away from the Brillouin-zone center will be involved in the Raman scattering, whi... The fundamental momentum conservation requirement q - 0 for the Raman process is relaxed in the nanocrystal- lites (NCs), and phonons away from the Brillouin-zone center will be involved in the Raman scattering, which is well-known as the phonon confinement effect in NCs. This usually gives a downshift and asymmetric broadening of the Raman peak in various NCs. Recently, the A1 mode of 1L MoS2 NCs is found to exhibit a blue shift and asymmetric broadening toward the high-frequency side [Chem. Soc. Rev. 44 (2015) 2757 and Phys. Rev. B 91 (2015) 195411]. In this work, we carefully check this issue by studying Raman spectra of lL MoS2 NCs prepared by the ion implantation technique in a wide range of ion-implanted dosage. The same confinement coefficient is used for both E' and A'1 modes in 1L MoS2 NCs since the phonon uncertainty in an NC is mainly determined by its domain size. The asymmetrical broadening near the A'1 and E' modes is attributed to the appearance of defect-activated phonons at the zone edge and the intrinsic asymmetrical broadening of the two modes, where the anisotropy of phonon dispersion curves along Г-K and Г- M is also considered. The photoluminescence spectra confirm the formation of small domain size of 1L MoS2 nanocrystallites in the ion-implanted 1L MoS2. This study provides not only an approach to quickly probe phonon dispersion trends of 2D materials away from Г by the Raman scattering of the corresponding NCs, but also a reference to completely understand the confinement effect of different modes in various nanomaterials. 展开更多
关键词 of is NC as Phonon Confinement Effect in Two-dimensional Nanocrystallites of Monolayer MoS2 to Probe Phonon Dispersion trends Away from Brillouin-Zone Center mode in from
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Study on the technologies development trend of high speed EMUs 被引量:1
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作者 Chunfang Lu Zunsong Ren Chengxian Ma 《High-Speed Railway》 2023年第1期1-5,共5页
High speed railway technologies are rapidly development in the world.The total distance of the high speed railway is more than 40,000 kilometers in China,and many types of high speed Electrical Multi-Units(EMUs)are op... High speed railway technologies are rapidly development in the world.The total distance of the high speed railway is more than 40,000 kilometers in China,and many types of high speed Electrical Multi-Units(EMUs)are operated.The top operation velocity of the train reaches 350 km/h.New science and technologies are developing rapidly.New generation technologies such as the information technology,intelligent manufacturing,new material and processing,innovating design philosophy have revolutionary influence on the high speed train.It promotes the high speed train performance such as intelligence,reliable operation and environment-friendly.Based on many years investigation of the trend of the technology development and requirement of general public,the trend of technology development in five aspects are presented in this paper.The five aspects include economic applicability,high speed and high efficiency,green and low carbon,intelligent safety,comfortable and high quality. 展开更多
关键词 High speed EMUs TECHNOLOGIES Development trend Economic applicability Intelligence
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Understanding the Correlations between Social Attention and Topic Trends of Scientific Publications 被引量:1
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作者 Xianlei Dong Jian Xu +3 位作者 Ying Ding Chenwei Zhang Kunpeng Zhang Min Song 《Journal of Data and Information Science》 2016年第1期28-49,共22页
Purpose: We propose and apply a simplified nowcasting model to understand the correlations between social attention and topic trends of scientific publications. Design/methodology/approach: First, topics are generat... Purpose: We propose and apply a simplified nowcasting model to understand the correlations between social attention and topic trends of scientific publications. Design/methodology/approach: First, topics are generated from the obesity corpus by using the latent Dirichlet allocation (LDA) algorithm and time series of keyword search trends in Google Trends are obtained. We then establish the structural time series model using data from January 2004 to December 2012, and evaluate the model using data from January 2013. We employ a state-space model to separate different non-regression components in an observational time series (i.e. the tendency and the seasonality) and apply the "spike and slab prior" and stepwise regression to analyze the correlations between the regression component and the social media attention. The two parts are combined using Markov-chain Monte Carlo sampling techniques to obtain our results. Findings: The results of our study show that (1) the number of publications on child obesity increases at a lower rate than that of diabetes publications; (2) the number of publication on a given topic may exhibit a relationship with the season or time of year; and (3) there exists a correlation between the number of publications on a given topic and its social media attention, i.e. the search frequency related to that topic as identified by Google Trends. We found that our model is also able to predict the number of publications related to a given topic. 展开更多
关键词 First we study a correlation rather than causality between topics'trends and social media. As a result the relationships might not be robust so we cannot
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Analysing the Trend of UK’s Rural Development
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作者 徐瑛 敖维平 《海外英语》 2019年第13期266-268,共3页
Rural development is an important indicator of a country’s integrated development.It apparently seems there are small amount of direct stakeholders in rural development,but it is one of the ribs of national industry ... Rural development is an important indicator of a country’s integrated development.It apparently seems there are small amount of direct stakeholders in rural development,but it is one of the ribs of national industry development,the last mile for improving the people’s life quality in most developing counties.Though the issues of new land reform enforcement,unemployment,degraded ecosystem and low productivity on agriculture are nerve-racking for UK’s government,the rural development has undoubtedly been setting an example for the world,especially for developing countries.The paper,on the basis of author’s personal observing in dozens of UK’s rural areas and exchanging ideas with some experts there in 2017,starts with a drawing of UK rural outlook from demographic point of view;then follows the present challenges of rural development;and ends up with analysing the models of rural development. 展开更多
关键词 UK RURAL DEVELOPMENT trend
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