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Hans A.Panofsky’s Integral Similarity Function—At Fifty
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作者 Gerhard Kramm Dillon J.Amaya +1 位作者 Thomas Foken Nicole Molders 《Atmospheric and Climate Sciences》 2013年第4期581-594,共14页
Fifty years ago, Hans A. Panofsky published a paper entitled Determination of stress from wind and temperature measurements. In his famous paper, he presented a new profile function for the mean horizontal wind speed ... Fifty years ago, Hans A. Panofsky published a paper entitled Determination of stress from wind and temperature measurements. In his famous paper, he presented a new profile function for the mean horizontal wind speed under the condition of diabatic stratification that includes his integral similarity function. With his integral similarity function, he opened the door for Monin-Obukhov scaling in a wide range of micrometeorological and microclimatological applications. In a historic survey ranging from the sixties of the past century down to the present days, we present integral similarity functions for momentum, sensible heat, and water vapor for both unstable and stable stratification, where on the one hand free convection condition and on the other hand strongly stable stratification are addressed. 展开更多
关键词 Profile functions Monin-Obukhov Scaling Prandtl-Obukhov-Priestley Scaling Local similarity function Integral similarity function Obukhov Number Gradient Richardson Number Flux Richardson Number
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Discrepancy and Applicability of Various Similarity Functions in Flux Calculations Under Stable Conditions 被引量:1
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作者 郭晓峰 张宏升 +3 位作者 蔡旭晖 康凌 李万彪 杜金林 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第4期644-654,共11页
Based on data obtained during the Hualhe River Basin Experiment (HUBEX) in 1999, this study intends to detect the quantitative discrepancies in the momentum (τ0), sensible heat (H0) and latent heat (E0) fluxe... Based on data obtained during the Hualhe River Basin Experiment (HUBEX) in 1999, this study intends to detect the quantitative discrepancies in the momentum (τ0), sensible heat (H0) and latent heat (E0) fluxes among six sets of similarity functions with the aerodynamic method. It also aims to clarify the applicability of the functions under stable conditions. The relative discrepancy was studied with the normalized transfer coefficients for τ0, H0 and E0, namely CD, CH and CQ, respectively. Except for one set of functions that adopted a rather small von Kármán's constant (0.365), the relative discrepancy in τ0 among the other functions was less than 10%, while that in H0(E0) sometimes reached 25% when the bulk Richardson number (R/B) was less than 0.07. The absolute discrepancy in the fluxes was studied with statistical computations. Among the six sets of functions, the discrepancy in τ0, H0 and E0 sometimes reached 0.03 kg m^-1 s^-2, 4 W m^-2 and 10 W m^-2, respectively, and the discrepancy in the energy balance ratio sometimes exceeded 0.1. Furthermore, when RiB exceeded the critical value (Ric) for a specific set of functions, no fluxes could be derived with the functions. It is therefore suggested that RiB be compared with Ric before computing the fluxes if RiB is less than Ric. Finally, two sets of nonlinear similarity functions are recommended, due to their unlimited applicability in terms of RiB. 展开更多
关键词 aerodynamic method turbulent flux surface layer similarity function energy balance
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INTS-MFS:A novel method to predict microRNA-disease associations by integrating network topology similarity and microRNA function similarity
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作者 BUWEN CAO JIAWEI LUO +2 位作者 SAINAN XIAO KAI ZHAO SHULING YANG 《BIOCELL》 SCIE 2022年第3期837-845,共9页
Identifying associations between microRNAs(miRNAs)and diseases is very important to understand the occurrence and development of human diseases.However,these existing methods suffer from the following limitation:first... Identifying associations between microRNAs(miRNAs)and diseases is very important to understand the occurrence and development of human diseases.However,these existing methods suffer from the following limitation:first,some disease-related miRNAs are obtained from the miRNA functional similarity networks consisting of heterogeneous data sources,i.e.,disease similarity,protein interaction network,gene expression.Second,little approaches infer disease-related miRNAs depending on the network topological features without the functional similarity of miRNAs.In this paper,we develop a novel model of Integrating Network Topology Similarity and MicroRNA Function Similarity(INTS-MFS).The integrated miRNA similarities are calculated based on miRNA functional similarity and network topological characteristics.INTS-MFS obtained AUC of 0.872 based on five-fold cross-validation and was applied to three common human diseases in case studies.As a results,30 out of top 30 predicted Prostatic Neoplasm-related miRNAs were included in the two databases of dbDEMC and PhenomiR2.0.29 out of top 30 predicted Lung Neoplasm-related miRNAs and Breast Neoplasm-related miRNAs were included in dbDEMC,PhenomiR2.0 and experimental reports.Moreover,INTS-MFS found unknown association with hsa-mir-371a in breast cancer and lung cancer,which have not been reported.It provides biologists new clues for diagnosing breast and lung cancer. 展开更多
关键词 Disease-related miRNA MiRNA-disease association functional similarity Network topological similarity
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Turbulence Intensity and Turbulent Kinetic Energy Parameters over a Heterogeneous Terrain of Loess Plateau 被引量:5
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作者 YUE Ping ZHANG Qiang +2 位作者 WANG Runyuan LI Yaohui WANG Sheng 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第9期1291-1302,共12页
A deep understanding of turbulence structure is important for investigating the characteristics of the atmospheric boundary layer,especially over heterogeneous terrain.In the present study,turbulence intensity and tur... A deep understanding of turbulence structure is important for investigating the characteristics of the atmospheric boundary layer,especially over heterogeneous terrain.In the present study,turbulence intensity and turbulent kinetic energy(TKE)parameters are analyzed for different conditions with respect to stability,wind direction and wind speed over a valley region of the Loess Plateau of China during December 2003 and January 2004.The purpose of the study is to examine whether the observed turbulence intensity and TKE parameters satisfy Monin–Obukhov similarity theory(MOST),and analyze the wind shear effect on,and thermal buoyancy function of,the TKE,despite the terrain heterogeneity.The results demonstrate that the normalized intensity of turbulence follows MOST for all stability in the horizontal and vertical directions,as well as the normalized TKE in the horizontal direction.The shear effect of the wind speed in the Loess Plateau region is strong in winter and could enhance turbulence for all stability conditions.During daytime,the buoyancy and shear effect together constitute the generation of TKE under unstable conditions.At night,the contribution of buoyancy to TKE is relatively small,and mechanical shearing is the main production form of turbulence. 展开更多
关键词 heterogeneous terrain turbulence intensity turbulent kinetic energy Monin–Obukhov similarity function
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A generalized evidence distance 被引量:1
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作者 Hongming Mo Xi Lu Yong Deng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期470-476,共7页
How to efficiently measure the distance between two basic probability assignments(BPAs) is an open issue. In this paper, a new method to measure the distance between two BPAs is proposed, based on two existing measu... How to efficiently measure the distance between two basic probability assignments(BPAs) is an open issue. In this paper, a new method to measure the distance between two BPAs is proposed, based on two existing measures of evidence distance. The new proposed method is comprehensive and generalized. Numerical examples are used to illustrate the effectiveness of the proposed method. 展开更多
关键词 Dempster-Shafer evidence(D-S) theory basic probability assignment(BPA) belief function evidence distance similarity function
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CRISE: Toward Better Understanding of COVID-19 Psychological Impact during Lockdown
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作者 Hussein Baalbaki Hassan Harb +3 位作者 Chamseddine Zaki Youssef Alakoury Layla Tannoury Michel Nabaa 《Journal of Computer and Communications》 2021年第8期13-31,共19页
Recently, the COVID-19 emerged in China and propagated around all the world has threatened millions of people and affected most countries and governments at several sides such as economical, educational, tourism, heal... Recently, the COVID-19 emerged in China and propagated around all the world has threatened millions of people and affected most countries and governments at several sides such as economical, educational, tourism, healthcare, etc. Indeed, one of the most important challenges that directly affect the people is the psychological side due to the harsh policies imposed by public authorities in most countries. In this paper, we propose a framework called CRISE that allows studying and understanding the psychological effect of COVID-19 during the lockdown period. Mainly, CRISE consists of four data stages: Collection, tRansformation, reductIon, and cluStEring. The first stage collects data from more than 2000 participants through a questionnaire containing attributes related to psychological effect before and during the lockdown. The second stage aims to preprocess the data before performing the study stage. The third stage proposes a model that finds the similarities among the attributes, based on the correlation matrix, to reduce its number. Finally, the fourth stage introduces a new version of Kmeans algorithm, called as Jaccard-based Kmeans (JKmeans), that allows to group participants having similar psychological situation in the same cluster for a later analysis. We show the effectiveness of CRISE in terms of clustering accuracy and understanding the psychological effect of COVID-19. 展开更多
关键词 COVID-19 Mental Health Data Clustering similarity function Data Reduction Correlation Matrix
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Multidimensional diversity of bird communities across spatial variation of land cover in Zoige on the eastern Qinghai-Tibetan Plateau
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作者 Aichun Xu Maojun Zhong +7 位作者 Ke Tang Xiaoyi Wang Chen Yang Haigen Xu Jianfeng Yi Wei Liu Chunlan Zhang Junhua Hu 《Avian Research》 CSCD 2021年第2期150-160,共11页
Background:Spatial variation of land cover can result in the changes of community similarities and biotic homog-enization,whereby the increasing similarity would reduce the adaptive capacity of biotic assemblages to f... Background:Spatial variation of land cover can result in the changes of community similarities and biotic homog-enization,whereby the increasing similarity would reduce the adaptive capacity of biotic assemblages to further disturbance,and degenerate ecosystem services they offer.However,it remains scarce to integrate multidimensional diversity for unveiling how variations in land cover may influence the patterns and processes of biotic homogeniza-tion in the Anthropocene.In this study,we examined how spatial variation of land cover could alter taxonomic,phy-logenetic and functional homogenization of bird communities simultaneously in a compound ecosystem of Zoige Marsh on the eastern Qinghai-Tibetan Plateau.Acting as the largest alpine marsh and peatland in the world,Zoige Marsh has undergone great changes in the land cover pattern due to climate change and anthropogenic activities.Methods:We conducted transect surveys for bird communities over six years(2014‒2019)during breeding sea-sons in four main land cover types(meadow,woodland,village and marsh),representing the spatial variation of land covers in the study area.We compared multidimensional diversity(taxonomic,phylogenetic and functional diver-sity)among land covers to assess the effects of spatial variation in land cover type on bird communities,particularly whether this variation has homogenized biotic communities.Results:Bird communities during breeding seasons were different and complementary in the four land covers.Taxonomic,phylogenetic and functional similarities were significantly lower in meadow than in the other three types,i.e.woodland,village and marsh.However,when we controlled for the effects of taxonomic similarities,the pattern of phylogenetic similarities almost reversed,with the highest standardized effect size(SES)phylogenetic similarity in meadow;and we found no significant difference in SES functional similarity among land covers.Conclusions:Our results suggest that spatial variation of land cover can play a crucial role in regulating multiple dimensions of bird diversity in Zoige Marsh.The findings indicate that taxonomic,phylogenetic and functional homogenization of bird communities may differently response to the variation of land covers.It thus highlights not only the relative roles of different land covers in maintaining biodiversity and community structures of birds,but also the urgency of retarding ecosystem degradations on the eastern Qinghai-Tibetan Plateau. 展开更多
关键词 Bird conservation Biotic homogenization functional similarity Land cover types Phylogenetic similarity
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SysFinder:A customized platform for search,comparison and assisted design of appropriate animal models based on systematic similarity
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作者 Shuang Yang Guoqing Zhang +6 位作者 Wan Liu Zhen Wang Jifeng Zhang Dongshan Yang Y.Eugene Chen Hong Sun Yixue Li 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2017年第5期251-258,共8页
Animal models are increasingly gaining values by cross-comparisons of response or resistance to clinical agents used for patients.However,many disease mechanisms and drug effects generated from animal models are not t... Animal models are increasingly gaining values by cross-comparisons of response or resistance to clinical agents used for patients.However,many disease mechanisms and drug effects generated from animal models are not transferable to human.To address these issues,we developed SysFinder(http://lifecenter.sgst.cn/SysFinder),a platform for scientists to find appropriate animal models for translational research.SysFinder offers a "topic-centered" approach for systematic comparisons of human genes,whose functions are involved in a specific scientific topic,to the corresponding homologous genes of animal models.Scientific topic can be a certain disease,drug,gene function or biological pathway.SysFinder calculates multi-level similarity indexes to evaluate the similarities between human and animal models in specified scientific topics.Meanwhile,SysFinder offers species-specific information to investigate the differences in molecular mechanisms between humans and animal models.Furthermore,SysFinder provides a userfriendly platform for determination of short guide RNAs(sgRNAs) and homology arms to design a new animal model.Case studies illustrate the ability of SysFinder in helping experimental scientists.SysFinder is a useful platform for experimental scientists to carry out their research in the human molecular mechanisms. 展开更多
关键词 Database Animal models function similarity
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Deformable Registration of Digital Images 被引量:1
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作者 管伟光 解林 马颂德 《Journal of Computer Science & Technology》 SCIE EI CSCD 1998年第3期246-260,共15页
This paper proposes a novel elastic model and presents a deformable registration method based on the model. The method registers images without the need to extract features from the images, and therefore works directl... This paper proposes a novel elastic model and presents a deformable registration method based on the model. The method registers images without the need to extract features from the images, and therefore works directly on grey-level images. A new similarity metric is given on which the formation of external forces is based. The registration method, taking the coarse-to-fine strategy constructs external forces in larger scales for the first few iterations to rely more on global evidence, and then in smaller scales for later iterations to allow local relinements. The stiffness of the elastic body decreases as the process proceeds.To make it widely applicable, the method is not restricted to any trpe of transformation. The variations between images are thought as general free-form deformations.Because the elastic model designed is linearized, it can be solved very efficiently with high accuracy.The method has been successfully tested on MRI images. It will certainly find other uses such as matching time-varying sequences of pictures for moion analysis,fitting templates into images for non-rigid object recognition, maching stereo images for shape recovery etc. 展开更多
关键词 Image registration deformable model deformable registration local similarity function hierarchy multiscale
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Cancellation of nonlinear distortion based on integration of FCM clustering algorithm and adaptive-two-stage linear approximation 被引量:1
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作者 WANG Gui-ye ZOU Wei-xia +2 位作者 WANG Zhen-yu DU Guang-long GAO Ying 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2014年第3期18-22,共5页
A hybrid system of the fuzzy c-means (FCM) clustering algorithm and adaptive-two-stage linear approximation was presented for nonlinear distortion cancellation of radio frequency (RF) power amplifier (PA). This ... A hybrid system of the fuzzy c-means (FCM) clustering algorithm and adaptive-two-stage linear approximation was presented for nonlinear distortion cancellation of radio frequency (RF) power amplifier (PA). This mechanism can effectively eliminate noise, adaptively model PA's instantaneous change, and efficiently correct nonlinear distortion. This article puts forward the FCM clustering algorithm for clustering received signals to eliminate white noise, and then uses the adaptive-two-stage linear approximation to fit the inverse function of the amplitude's and phase's nonlinear mapping during the training phase. Parameters of the linear function and similarity function are trained using the gradient-descent and minimum mean-square error criteria. The proposed approach's training results is directly employed to eliminate sampling signal's nonlinear distortion. This hybrid method is realized easier than the multi-segment linear approximation and could reduce the received signal's bit error rate (BER) more efficiently. 展开更多
关键词 PA nonlinear distortion cancellation FCM clustering algorithm similarity function adaptive-two-stage linear approximation
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Visual polysemy and synonymy:toward near-duplicate image retrieval
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作者 Manni DUAN Xiuqing WU 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2010年第4期419-429,共11页
that are duplicate or near duplicate to a query image.One of the most popular and practical methods in near-duplicate image retrieval is based on bag-of-words(BoW)model.However,the fundamental deficiency of current Bo... that are duplicate or near duplicate to a query image.One of the most popular and practical methods in near-duplicate image retrieval is based on bag-of-words(BoW)model.However,the fundamental deficiency of current BoW method is the gap between visual word and image’s semantic meaning.Similar problem also plagues existing text retrieval.A prevalent method against such issue in text retrieval is to eliminate text synonymy and polysemy and therefore improve the whole performance.Our proposed approach borrows ideas from text retrieval and tries to overcome these deficiencies of BoW model by treating the semantic gap problem as visual synonymy and polysemy issues.We use visual synonymy in a very general sense to describe the fact that there are many different visual words referring to the same visual meaning.By visual polysemy,we refer to the general fact that most visual words have more than one distinct meaning.To eliminate visual synonymy,we present an extended similarity function to implicitly extend query visual words.To eliminate visual polysemy,we use visual pattern and prove that the most efficient way of using visual pattern is merging visual word vector together with visual pattern vector and obtain the similarity score by cosine function.In addition,we observe that there is a high possibility that duplicates visual words occur in an adjacent area.Therefore,we modify traditional Apriori algorithm to mine quantitative pattern that can be defined as patterns containing duplicate items.Experiments prove quantitative patterns improving mean average precision(MAP)significantly. 展开更多
关键词 near-duplicate image retrieval bag-of-words(BoW)model visual synonymy visual polysemy extended similarity function query expansion visual pattern
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Machine Knowledge and Human Cognition 被引量:1
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作者 Fashen Li Lian Li +10 位作者 Jianping Yin Liang Huang Qingguo Zhou Ning An Yong Zhang Li Liu Jialin Zhang Kun Kuang Lei Yang Zhixi Wu Lianchun Yu 《Big Data Mining and Analytics》 EI 2020年第4期292-299,共8页
Intelligent machines are knowledge systems with unique knowledge structure and function.In this paper,we discuss issues including the characteristics and forms of machine knowledge,the relationship between knowledge a... Intelligent machines are knowledge systems with unique knowledge structure and function.In this paper,we discuss issues including the characteristics and forms of machine knowledge,the relationship between knowledge and human cognition,and the approach to acquire machine knowledge.These issues are of great significance to the development of artificial intelligence. 展开更多
关键词 intelligent machine machine knowledge human cognition knowledge interpretation principle of functional similarity Probable Approximative Correction(PAC)model
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