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Essential proteins identification method based on four-order distances and subcellular localization information
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作者 卢鹏丽 钟雨 杨培实 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期765-772,共8页
Essential proteins are inseparable in cell growth and survival. The study of essential proteins is important for understanding cellular functions and biological mechanisms. Therefore, various computable methods have b... Essential proteins are inseparable in cell growth and survival. The study of essential proteins is important for understanding cellular functions and biological mechanisms. Therefore, various computable methods have been proposed to identify essential proteins. Unfortunately, most methods based on network topology only consider the interactions between a protein and its neighboring proteins, and not the interactions with its higher-order distance proteins. In this paper, we propose the DSEP algorithm in which we integrated network topology properties and subcellular localization information in protein–protein interaction(PPI) networks based on four-order distances, and then used random walks to identify the essential proteins. We also propose a method to calculate the finite-order distance of the network, which can greatly reduce the time complexity of our algorithm. We conducted a comprehensive comparison of the DSEP algorithm with 11 existing classical algorithms to identify essential proteins with multiple evaluation methods. The results show that DSEP is superior to these 11 methods. 展开更多
关键词 protein–protein interaction(PPI)network essential proteins four-order distances subcellular localization information
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Extended Lorenz majorization and frequencies of distances in an undirected network
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作者 Leo Egghe 《Journal of Data and Information Science》 CSCD 2024年第1期1-10,共10页
Purpose:To contribute to the study of networks and graphs.Design/methodology/approach:We apply standard mathematical thinking.Findings:We show that the distance distribution in an undirected network Lorenz majorizes t... Purpose:To contribute to the study of networks and graphs.Design/methodology/approach:We apply standard mathematical thinking.Findings:We show that the distance distribution in an undirected network Lorenz majorizes the one of a chain.As a consequence,the average and median distances in any such network are smaller than or equal to those of a chain.Research limitations:We restricted our investigations to undirected,unweighted networks.Practical implications:We are convinced that these results are useful in the study of small worlds and the so-called six degrees of separation property.Originality/value:To the best of our knowledge our research contains new network results,especially those related to frequencies of distances. 展开更多
关键词 majorization Lorenz curves NETWORKS shortest path distance GRAPHS
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Robust free-space optical frequency transfer in time-varying link distances conditions
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作者 童周 刘雷 +6 位作者 王家亮 操前 金志成 应康 韩申生 韩正甫 桂有珍 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期271-276,共6页
Future inter-satellite clock comparison on high orbit will require optical time and frequency transmission technology between moving objects.Here,we demonstrate robust optical frequency transmission under the conditio... Future inter-satellite clock comparison on high orbit will require optical time and frequency transmission technology between moving objects.Here,we demonstrate robust optical frequency transmission under the condition of variable link distance.This variable link is accomplished by the relative motion of a single telescope fixed on the experimental platform to a corner-cube reflector(CCR)installed on a sliding guide.Two acousto–optic modulators with different frequencies are used to separate forward signal from backward signal.With active phase noise suppression,when the CCR moves back and forth at a constant velocity of 20 cm/s and an acceleration of 20 cm/s^(2),we achieve the best frequency stability of 1.9×10^(-16) at 1 s and 7.9×10^(-19) at 1000 s indoors.This work paves the way for future studying optical frequency transfer between ultra-high-orbit satellites. 展开更多
关键词 FREE-SPACE optical frequency transfer variable link distance
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Multi-Attribute Couplings-Based Euclidean and Nominal Distances for Unlabeled Nominal Data
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作者 Lei Gu Furong Zhang Li Ma 《Computers, Materials & Continua》 SCIE EI 2023年第6期5911-5928,共18页
Learning unlabeled data is a significant challenge that needs to han-dle complicated relationships between nominal values and attributes.Increas-ingly,recent research on learning value relations within and between att... Learning unlabeled data is a significant challenge that needs to han-dle complicated relationships between nominal values and attributes.Increas-ingly,recent research on learning value relations within and between attributes has shown significant improvement in clustering and outlier detection,etc.However,typical existing work relies on learning pairwise value relations but weakens or overlooks the direct couplings between multiple attributes.This paper thus proposes two novel and flexible multi-attribute couplings-based distance(MCD)metrics,which learn the multi-attribute couplings and their strengths in nominal data based on information theories:self-information,entropy,and mutual information,for measuring both numerical and nominal distances.MCD enables the application of numerical and nominal clustering methods on nominal data and quantifies the influence of involving and filtering multi-attribute couplings on distance learning and clustering perfor-mance.Substantial experiments evidence the above conclusions on 15 data sets against seven state-of-the-art distance measures with various feature selection methods for both numerical and nominal clustering. 展开更多
关键词 Nominal data distance metrics attribute couplings dissimilarity measures
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Influences of Different Distances between Ridges or Plants on Yield of Sweet Potatoes
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作者 黄志谋 杨新笋 +3 位作者 柴沙沙 杨汉 刘伟 马志强 《Agricultural Science & Technology》 CAS 2017年第4期624-626,共3页
Based on the combination test of various distances between ridges or plants, the influences of corresponding cultivation techniques on the per unit area yield of a variety of sweet potatoes Xushu 22 in Xianning City w... Based on the combination test of various distances between ridges or plants, the influences of corresponding cultivation techniques on the per unit area yield of a variety of sweet potatoes Xushu 22 in Xianning City were analyzed. The results show that different distances between ridges or plants had significant effects on the per unit area yield of Xushu 22; when the distances between ridges and plants for Xushu 22 planted in the city were 80 and 21 cm respectively, the per u- nit area yield of Xushu 22 was the highest, up to 48 340.7 kg/hm2. 展开更多
关键词 Sweet potatoes Xushu 22 distances between ridges distances be- tween plants Per unit area yield
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Investigation of True Ni^(2+)-Halide Distances in Alkali Halide Lattices
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作者 Xuanrong MA(Department of Physics, Ningxia University, Yinchuan, 750021, China)Maolu DU(Institute of Solid State Physics, Sichuan Normal University, Chengdu, 610066, China)(To whom correspondence should be addressed) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1994年第2期154-156,共3页
Using the μKα model of Ni2+-6X- cluster, the true distances between impurity Ni2+ cation and halide anion in alkali halide lattices are estimated from the optical spectra data. The results suggest that the true impu... Using the μKα model of Ni2+-6X- cluster, the true distances between impurity Ni2+ cation and halide anion in alkali halide lattices are estimated from the optical spectra data. The results suggest that the true impurity cation- ligand anion distances are close to the sum of ionic radii of the impurity cation and ligand anion but not the cation - anion distance of the perfect lattices in the case of that the ionic radius of host cation is more larger than that of impurity cation 展开更多
关键词 TRUE Cl Br Investigation of True Ni Halide distances in Alkali Halide Lattices
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Effect of Distances from Different Trees Species on the Properties of Mollic Horizon
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作者 Mohammed Ali Fayyadh 《Journal of Agricultural Science and Technology(A)》 2013年第8期581-591,共11页
The study area is located in Duhok province-Kurdistan region-Northern Iraq and including two locations the first location is situated in Galbook village and the vegetation cover is trees of (Quercus aegilops L.), th... The study area is located in Duhok province-Kurdistan region-Northern Iraq and including two locations the first location is situated in Galbook village and the vegetation cover is trees of (Quercus aegilops L.), the second location is situated in Koradeer village that covered with threes of Prunus dulcis (Mill.) Webb.. Disturbed surface soil samples at depth 0-30 cm were collected at four different distances (1, 5, 10 and 15 m) from the tree with randomized selection three trees in each study location. Soil organic matter decreases with increasing distances from tree in both locations under two different trees species, which is attributed to the effect of tree crown. Ordinarily, organic matter content in both locations correspond to the requirements of Mollisols. Statistical analysis of data showed significant differences in organic matter content between locations. Cation exchange capacity is high under tree crown and decreasing with distances from tree in both locations, as a result of decreasing organic matter and increasing calcium carbonate with distances. Commonly soil pH is slightly increased with increasing distances from tree because of increasing calcium carbonate with distances and decreasing organic matter content. Calcium was not uniform with distances and Mg decreasing with distances in both locations. The values of fine clay/coarse clay and fine clay/total clay of soil samples confirm development of the soils under study. Porosity percentage under tree crown is high and decreasing with distances. Soil bulk density was increased with distances in both locations, as a result of decreasing organic matter content with distances. This study aims to explain the effect of tree distances and species on the mollic horizon properties. 展开更多
关键词 Tree species distances MOLLISOLS physical properties chemical properties.
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Cosmological Distances in Closed Model of the Universe
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作者 Fadel A. Bukhari 《International Journal of Astronomy and Astrophysics》 2013年第2期199-203,共5页
Four Cosmological distances were determined in the light of the closed cosmic model which was presented in a previous study. Each of these distances was obtained in terms of the redshift of an extragalactic object. It... Four Cosmological distances were determined in the light of the closed cosmic model which was presented in a previous study. Each of these distances was obtained in terms of the redshift of an extragalactic object. It is found that the luminosity distance of the extragalactic object in the closed cosmic model, the observed model and model are approximately the same up to z = 0.1535. However, the luminosity distance in the close cosmic model approximately agrees with its value in the observed model up to z = 0.6442. Estimations of the horizon distance of the universe, the total mass and the mass of matter within the horizon distance, the equivalent numbers of the Milky Way-like galaxies and the Coma-like clusters of galaxies to the mass of matter were computed in the closed cosmic model at the present time. 展开更多
关键词 EXTRAGALACTIC distances COSMOLOGY COSMIC Dynamics COSMOLOGICAL Parameter
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Cosmological Distances in Five General Cosmic Models
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作者 Fadel A. Bukhari 《International Journal of Astronomy and Astrophysics》 2013年第2期183-188,共6页
Four cosmological distances were investigated in the light of the five general cosmic models which were developed in a previous study. These are the proper distance, luminosity distance, angular diameter distance and ... Four cosmological distances were investigated in the light of the five general cosmic models which were developed in a previous study. These are the proper distance, luminosity distance, angular diameter distance and distance modulus. Each of these distances was studied in terms of the redshift of the extragalactic objects. Estimations of the horizon distance of the universe, the total mass and the mass of matter within the horizon distance, the equivalent numbers of the Milky Way-like galaxies and the Coma-like clusters of galaxies to the mass of matter were determined in the general models at the present time. 展开更多
关键词 EXTRAGALACTIC distances COSMOLOGY COSMIC Dynamics
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Distances Scale Determination for a Planetary Nebula in Galactic Bulge
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作者 Sundus A. Abdullah Nathera A. Ali Mohamed A. Sallih 《International Journal of Astronomy and Astrophysics》 2013年第2期81-86,共6页
Planetary Nebulae (PN) distances represent the fundamental parameter for the determination the physical properties of the central star of PN. In this paper the distances scale to Planetary Nebulae in the Galactic bulg... Planetary Nebulae (PN) distances represent the fundamental parameter for the determination the physical properties of the central star of PN. In this paper the distances scale to Planetary Nebulae in the Galactic bulge were calculated related to previous distances scales. The proposed distance scale was done by recalibrated the previous distance scale technique CKS/D82. This scale limited for nearby PN (D ≤ 3.5 kpc), so the surface fluxes less than other distance scales. With these criteria the results showed that the proposed distance scale is more accurate than other scales related to the observations for adopted sample of PN distances, also the limit of ionized radius (Rio) for all both optically thick and optically thin in the rang of sizes (0.45 > Rio (pc) > 0.03). 展开更多
关键词 PLANETARY NEBULAE MASSES distances PLANETARY NEBULAE
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Information-Based Numerical Distances between Equilibrium and Non-Equilibrium States
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作者 Angel Ricardo Plastino Gustvo Luis Ferri +1 位作者 Mario Carlos Rocca Angelo Plastino 《Journal of Modern Physics》 2020年第7期1031-1043,共13页
We consider a typical master equation describing thermal time-evolution. In parallel, we also consider a quasi static canonical description of the same problem. We are able to devise a way of numerically comparing the... We consider a typical master equation describing thermal time-evolution. In parallel, we also consider a quasi static canonical description of the same problem. We are able to devise a way of numerically comparing these two treatments and concoct a distance-measure between them. In this way, one is in a position to know how far or close equilibrium and off-equilibrium can get. The first, rather surprising observation, is that our systems lose structural details as N grows. Also, the time-evolution of the distance between the two pertinent probability distributions is quite sensitive to the heating-cooling process. 展开更多
关键词 Information Theory Master Equation Thermal Time-Evolution Equilibrium-Off Equilibrium distances
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Assessment of different genetic distances in constructing cotton core subset by genotypic values 被引量:7
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作者 Jian-cheng WANG Jin HU +1 位作者 Xin-xian HUANG Sheng-chun XU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第5期356-362,共7页
One hundred and sixty-eight genotypes of cotton from the same growing region were used as a germplasm group to study the validity of different genetic distances in constructing cotton core subset. Mixed linear model a... One hundred and sixty-eight genotypes of cotton from the same growing region were used as a germplasm group to study the validity of different genetic distances in constructing cotton core subset. Mixed linear model approach was employed to unbiasedly predict genotypic values of 20 traits for eliminating the environmental effect. Six commonly used genetic distances(Euclidean,standardized Euclidean,Mahalanobis,city block,cosine and correlation distances) combining four commonly used hierarchical cluster methods(single distance,complete distance,unweighted pair-group average and Ward's methods) were used in the least distance stepwise sampling(LDSS) method for constructing different core subsets. The analyses of variance(ANOVA) of different evaluating parameters showed that the validities of cosine and correlation distances were inferior to those of Euclidean,standardized Euclidean,Mahalanobis and city block distances. Standardized Euclidean distance was slightly more effective than Euclidean,Mahalanobis and city block distances. The principal analysis validated standardized Euclidean distance in the course of constructing practical core subsets. The covariance matrix of accessions might be ill-conditioned when Mahalanobis distance was used to calculate genetic distance at low sampling percentages,which led to bias in small-sized core subset construction. The standardized Euclidean distance is recommended in core subset construction with LDSS method. 展开更多
关键词 Core subset Mixed linear model Least distance stepwise sampling (LDSS) method Standardized Euclidean distance Mahalanobis distance
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An Improved DV-Hop Localization Algorithm Based on Hop Distances Correction 被引量:8
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作者 Guiqi Liu Zhihong Qian Xue Wang 《China Communications》 SCIE CSCD 2019年第6期200-214,共15页
DV-Hop localization algorithm has greater localization error which estimates distance from an unknown node to the different anchor nodes by using estimated average size of a hop to achieve the location of the unknown ... DV-Hop localization algorithm has greater localization error which estimates distance from an unknown node to the different anchor nodes by using estimated average size of a hop to achieve the location of the unknown node.So an improved DV-Hop localization algorithm based on correctional average size of a hop,HDCDV-Hop algorithm,is proposed.The improved algorithm corrects the estimated distance between the unknown node and different anchor nodes based on fractional hop count information and relatively accurate coordinates of the anchor nodes information,and it uses the improved Differential Evolution algorithm to get the estimate location of unknown nodes so as to further reduce the localization error.Simulation results show that our proposed algorithm have lower localization error and higher localization accuracy compared with the original DV-Hop algorithm and other classical improved algorithms. 展开更多
关键词 WSN DV-HOP localization ALGORITHM HOP Distance CORRECTION IMPROVED Differential Evolution ALGORITHM
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Changes in Runout Distances of Debris Flows over Time in the Wenchuan Earthquake Zone 被引量:6
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作者 ZHANG Shuai ZHANG Li-Min +2 位作者 CHEN Hong-Xin YUAN Quan PAN Hua 《Journal of Mountain Science》 SCIE CSCD 2013年第2期281-292,共12页
A large number of debris flows occurred in the Wenchuan earthquake zone after the 12 May 2008 earthquake.The risks posed by these debris flows were rather high.An appropriate model is required to predict the possible ... A large number of debris flows occurred in the Wenchuan earthquake zone after the 12 May 2008 earthquake.The risks posed by these debris flows were rather high.An appropriate model is required to predict the possible runout distance and impacted area.This paper describes a study on the runout characteristics of the debris flows that occurred in the Wenchuan earthquake zone over the past four years.A total of 120 debris flows are analyzed.Separate multivariate regression models are established for the runout distances of hill-slope debris flows and channelized debris flows.The control variables include type of debris flow,debris flow volume,and elevation difference.Comparison of the debris flows occurring before and after the earthquake shows that the runout distance increased after the earthquake due to sufficient material supply and increased mobility of the source materials.In addition,the runout distances of annual debris flow events in 2008,2010 and 2011 are analyzed and compared.There is a tendency that the runout distance decreases over time due to the decreasing source material volume and possible changes of debris flow type.Comparison between the debris flows in the earthquake zone and the debris flows in Swiss Alps,Canada,Austria,and Japan shows that the former have a smaller mobility. 展开更多
关键词 Debris flow Rainfall Runout distance LANDSLIDE Wenchuan earthquake Risk assessment
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Fuzzy distances based FMAGDM compromise ratio method and application 被引量:2
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作者 Zhenfeng Rui Dengfeng Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期455-460,共6页
An extended compromise ratio method(CRM) based on fuzzy distances is developed to solve fuzzy multi-attribute group decision making problems in which weights of attributes and ratings of alternatives on attributes a... An extended compromise ratio method(CRM) based on fuzzy distances is developed to solve fuzzy multi-attribute group decision making problems in which weights of attributes and ratings of alternatives on attributes are expressed with values of linguistic variables parameterized using triangular fuzzy numbers.A compromise solution is determined by introducing the ranking index based on the concept that the chosen alternative should be as close as possible to the positive ideal solution and as far away from the negative ideal solution as possible simultaneously.This proposed method is compared with other existing methods to show its feasibility and effectiveness and illustrated with an example of the military route selection problem as one of the possible applications. 展开更多
关键词 fuzzy multi-attribute group decision making(FMAGDM) compromise ratio method(CRM) linguistic variable fuzzy number fuzzy distance.
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Fixed Point Results by Altering Distances in Fuzzy Metric Spaces 被引量:2
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作者 Ibtisam Masmali Sumitra Dalal Nasir Rehman 《Advances in Pure Mathematics》 2015年第6期377-382,共6页
We establish fixed point theorems in complete fuzzy metric space by using notion of altering distance, initiated by Khan et al. [Bull. Austral. Math. Soc. 30 (1984), 1-9]. Also, we find an affirmative answer in fuzzy ... We establish fixed point theorems in complete fuzzy metric space by using notion of altering distance, initiated by Khan et al. [Bull. Austral. Math. Soc. 30 (1984), 1-9]. Also, we find an affirmative answer in fuzzy metric space to the problem of Sastry [TamkangJ. Math., 31(3) (2000), 243-250]. 展开更多
关键词 Fixed POINTS Fuzzy METRIC SPACES Altering Distance Fixed Point RESULTS
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Minimum Time Overtaking Problem of Vehicle Handling Inverse Dynamics Based on Two Kinds of Safe Distances 被引量:1
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作者 You-Qun Zhao Xing-Long Zhang +1 位作者 Wen-Xin Zhang Fen Lin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第6期207-216,共10页
Overtaking accidents caused by improper operations performed by a driver occur frequently. However, most stud?ies on overtaking safety have neglected research into driver control input. A novel method is proposed to o... Overtaking accidents caused by improper operations performed by a driver occur frequently. However, most stud?ies on overtaking safety have neglected research into driver control input. A novel method is proposed to obtain the driver control input during the overtaking process. Meanwhile, to improve the safety of overtaking, two types of safe distances, and the time of the overtaking are considered. Path constraints are established when considering the two types of safe distances. An optimal control model is established to solve the minimum time maneuver under multiple constraints. Using the Gauss pseudospectral method, the optimal control problem is converted into a nonlinear pro?gramming problem, which is then solved through sequential quadratic programming(SQP). In addition, the e ective?ness of the proposed method is verified based on the results of a Carsim simulation. The simulation results show that by adopting an inverse dynamics method to solve the manipulation problem of the vehicle’s minimum overtaking time, the manipulation capability of a vehicle in completing an overtaking safely within the minimum time can be obtained. This method can provide a reference for research into the active safety of manned and unmanned vehicles. 展开更多
关键词 Handling inverse dynamics Safe distance OVERTAKING Optimal control Simulation
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Entanglement dynamics of a three-qubit system with different interatomic distances 被引量:1
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作者 封玲娟 张英杰 +1 位作者 张路 夏云杰 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期103-109,共7页
We investigate the tripartite entanglement dynamics of three two-level atoms in a multi-mode vacuum field. By considering the influences of the interatomic distance and the initial condition on the lower bound of conc... We investigate the tripartite entanglement dynamics of three two-level atoms in a multi-mode vacuum field. By considering the influences of the interatomic distance and the initial condition on the lower bound of concurrence and the tripartite negativity, we show that an optimal interatomic distance can be found to minimize the collective damping. Interestingly, at the same optimal distance, the tripartite entanglement would be maximized in the open dynamics process. In the case of shorter interatomic distance, the tripartite entanglement can display the oscillatory behavior in the initial short-time limit and be trapped in a stationary value in the long-time limit. In addition, the tripartite entanglement for the general situation with different interatomic distances is also discussed. 展开更多
关键词 quantum entanglement the lower bound of concurrence W state interatomic distance
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Minimum Clearance Offsets for Providing Desired Stopping Sight Distances at Simple Curves with Variable Operating Speeds 被引量:2
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作者 Timur Mauga 《Journal of Transportation Technologies》 2016年第3期107-117,共12页
Lateral clearance on the inside of horizontal curves is required by all geometric design guidelines in order to provide at least stopping sight distance. There already exist graphical models, analytical models, and de... Lateral clearance on the inside of horizontal curves is required by all geometric design guidelines in order to provide at least stopping sight distance. There already exist graphical models, analytical models, and design charts for determining minimum clearance offsets to meet the requirement. Some of these models determine the offsets based on constant design sight distance values on the assumption that drivers negotiate horizontal curves at constant speed. Therefore, those models are suitable for sites where there is no difference in speeds between tangent and curved sections. Past studies have reported that there are sites where drivers decelerate on entering horizontal curves and accelerate on departing from the curves. At those sites stopping sight distance for a given driver varies with driver location due to variable speed. This paper presents an analytical model and a chart for determining minimum offsets needed to provide desired sight distances at horizontal curves with variable operating speeds. At those sites the offsets yield roadside clearance boundaries that have transition arcs with performances that are similar to those of elliptical arcs. Therefore, practitioners may choose to use elliptical equations or equations and the chart developed herein. Results of this study will be of value to practitioners in the area of roadside design. 展开更多
关键词 Sight Distance Roadside Clearance Clearance Offsets Sightline Offsets Clearance Envelope
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Computations of wall distances by solving a transport equation
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作者 徐晶磊 阎超 范晶晶 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第2期141-150,共10页
Computations of wall distances still play a key role in modern turbulence modeling. Motivated by the expense involved in the computation, an approach solving partial differential equations is considered. An Euler-like... Computations of wall distances still play a key role in modern turbulence modeling. Motivated by the expense involved in the computation, an approach solving partial differential equations is considered. An Euler-like transport equation is proposed based on the Eikonal equation. Thus, the efficient algorithms and code components developed for solving transport equations such as Euler and Navier-Stokes equations can be reused. This article provides a detailed implementation of the transport equation in the Cartesian coordinates based on the code of computational fluid dynamics for missiles (MI- CFD) of Beihang University. The transport equation is robust and rapidly convergent by the implicit lower-upper symmetric Gauss-Seidel (LUSGS) time advancement and upwind spatial discretization. Geometric derivatives must also be upwind determined to ensure accuracy. Special treatments on initial and boundary conditions are discussed. This distance solving approach is successfully applied on several complex geometries with 1-1 blocking or overset grids. 展开更多
关键词 wall distance numerical simulation overset grid
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