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Effects of tissue absorption on calculation of mean photon path length using modified Beer-Lambert law 被引量:1
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作者 尚禹 桂志国 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第2期110-114,100,共6页
The mean path length(MPL)of photons is a critical parameter to calculate tissue absorption coefficient as well as blood oxygenation using modified Beer-Lambert law,where in the differential path factor(DPF)is often as... The mean path length(MPL)of photons is a critical parameter to calculate tissue absorption coefficient as well as blood oxygenation using modified Beer-Lambert law,where in the differential path factor(DPF)is often assumed as constant over range of tissue absorption.By utilizing the Monte Carlo(MC)simulation of photon migrations in the leg,this study used four approaches to estimate MPL,and compared them with that determined by the MPL definition.The simulation results indicate that the DPF is remarkably affected by tissue absorption,at approximate 10% variation.A linear model is suggested to calculate MPL for measurements of tissue absorption as well as blood oxygenation using modified Beer-Lambert law. 展开更多
关键词 mean path length(MPL) photon Monte Carlo(MC)simulation modified Beer-Lambert law tissue absorption
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An Intelligent Multi-robot Path Planning in a Dynamic Environment Using Improved Gravitational Search Algorithm 被引量:5
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作者 P.K.Das H.S.Behera +1 位作者 P.K.Jena B.K.Panigrahi 《International Journal of Automation and computing》 EI CSCD 2021年第6期1032-1044,共13页
This paper proposes a new methodology to optimize trajectory of the path for multi-robots using improved gravitational search algorithm(IGSA) in clutter environment. Classical GSA has been improved in this paper based... This paper proposes a new methodology to optimize trajectory of the path for multi-robots using improved gravitational search algorithm(IGSA) in clutter environment. Classical GSA has been improved in this paper based on the communication and memory characteristics of particle swarm optimization(PSO). IGSA technique is incorporated into the multi-robot system in a dynamic framework, which will provide robust performance, self-deterministic cooperation, and coping with an inhospitable environment. The robots in the team make independent decisions, coordinate, and cooperate with each other to accomplish a common goal using the developed IGSA. A path planning scheme has been developed using IGSA to optimally obtain the succeeding positions of the robots from the existing position in the proposed environment. Finally, the analytical and experimental results of the multi-robot path planning were compared with those obtained by IGSA, GSA and differential evolution(DE) in a similar environment. The simulation and the Khepera environment result show outperforms of IGSA as compared to GSA and DE with respect to the average total trajectory path deviation, average uncovered trajectory target distance and energy optimization in terms of rotation. 展开更多
关键词 Gravitational search algorithm multi-robot path planning average total trajectory path deviation average uncovered trajectory target distance average path length
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A novel similarity measure for mining missing links in long-path networks 被引量:1
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作者 Yijun Ran Tianyu Liu +1 位作者 Tao Jia Xiao-Ke Xu 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第6期56-64,共9页
Network information mining is the study of the network topology,which may answer a large number of applicationbased questions towards the structural evolution and the function of a real system.The question can be rela... Network information mining is the study of the network topology,which may answer a large number of applicationbased questions towards the structural evolution and the function of a real system.The question can be related to how the real system evolves or how individuals interact with each other in social networks.Although the evolution of the real system may seem to be found regularly,capturing patterns on the whole process of evolution is not trivial.Link prediction is one of the most important technologies in network information mining,which can help us understand the evolution mechanism of real-life network.Link prediction aims to uncover missing links or quantify the likelihood of the emergence of nonexistent links from known network structures.Currently,widely existing methods of link prediction almost focus on short-path networks that usually have a myriad of close triangular structures.However,these algorithms on highly sparse or longpath networks have poor performance.Here,we propose a new index that is associated with the principles of structural equivalence and shortest path length(SESPL)to estimate the likelihood of link existence in long-path networks.Through a test of 548 real networks,we find that SESPL is more effective and efficient than other similarity-based predictors in long-path networks.Meanwhile,we also exploit the performance of SESPL predictor and of embedding-based approaches via machine learning techniques.The results show that the performance of SESPL can achieve a gain of 44.09%over GraphWave and 7.93%over Node2vec.Finally,according to the matrix of maximal information coefficient(MIC)between all the similarity-based predictors,SESPL is a new independent feature in the space of traditional similarity features. 展开更多
关键词 structural equivalence shortest path length long-path networks missing links
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Cybersecurity: A Statistical Predictive Model for the Expected Path Length 被引量:5
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作者 Pubudu Kalpani Kaluarachchi Chris P. Tsokos Sasith M. Rajasooriya 《Journal of Information Security》 2016年第3期112-128,共17页
The object of this study is to propose a statistical model for predicting the Expected Path Length (expected number of steps the attacker will take, starting from the initial state to compromise the security goal—EPL... The object of this study is to propose a statistical model for predicting the Expected Path Length (expected number of steps the attacker will take, starting from the initial state to compromise the security goal—EPL) in a cyber-attack. The model we developed is based on utilizing vulnerability information along with having host centric attack graph. Utilizing the developed model, one can identify the interaction among the vulnerabilities and individual variables (risk factors) that drive the Expected Path Length. Gaining a better understanding of the relationship between vulnerabilities and their interactions can provide security administrators a better view and an understanding of their security status. In addition, we have also ranked the attributable variables and their contribution in estimating the subject length. Thus, one can utilize the ranking process to take precautions and actions to minimize Expected Path Length. 展开更多
关键词 VULNERABILITY Attack Graph Markov Model Security Evaluation Expected path Length CVSS
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A Formula of Average Path Length for Unweighted Networks
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作者 LIU Chun-Ping LIU Yu-Rong +1 位作者 HE Da-Ren ZHU Lu-Jin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期1017-1020,共4页
In this paper,based on the adjacency matrix of the network and its powers,the formulas are derived for theshortest path and the average path length,and an effective algorithm is presented.Furthermore,an example is pro... In this paper,based on the adjacency matrix of the network and its powers,the formulas are derived for theshortest path and the average path length,and an effective algorithm is presented.Furthermore,an example is providedto demonstrate the proposed method. 展开更多
关键词 complex network average path length adjacency matrix
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Nonlinear Relationship and Its Evolutionary Trace between Average Degree and Average Path Length of Edge Vertices of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Chen Xumei Guo Jianyuan 《Journal of Traffic and Transportation Engineering》 2024年第5期224-237,共14页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the average degree and the average path length of edge vertices of China aviation netwo... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the average degree and the average path length of edge vertices of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the average degree and average path length of edge vertices of China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Through regression analysis,it was found that the average degree had a logarithmic relationship with the average path length of edge vertices and the two parameters of the logarithmic relationship had linear evolutionary trace. 展开更多
关键词 China aviation network complex network average degree of edge vertices average path length of edge vertices logarithmic relationship evolutionary trace
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Probability Distribution of Average Length of Node Path and Its Evolution Trace of Aviation Network of China Based on Complex Network
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作者 Cheng Xiangjun Yang Fang Li Tao 《Journal of Traffic and Transportation Engineering》 2021年第2期41-52,共12页
In order to reveal the complex network feature and its evolution principle of aviation network of China,probability distribution and its evolution trace of average length of node path of aviation network of China were... In order to reveal the complex network feature and its evolution principle of aviation network of China,probability distribution and its evolution trace of average length of node path of aviation network of China were researched according to statistics data in years 1988,1994,2001,2008 and 2015 of civil aviation of China.Floyd algorithm to calculate the path length between any two nodes of network was applied and average length of node path of aviation network was obtained according to this algorithm.It was discovered that average length of node path to other nodes had normal distribution function in each year.At meantime,the location parameter and scale parameter of normal distribution function had linear evolution trace.Airline rate was an index to describe the density of airline.It was found that average length of node path of aviation network of China evolved synchronously with airline rate and they had linear relationship. 展开更多
关键词 Aviation network of China average length of node path probability distribution evolution trace airline rate
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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Average Path Length of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Xiaoxuan Li Yangqi 《Journal of Traffic and Transportation Engineering》 2024年第1期11-22,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the node average path length of China aviation network in 1988,1994,2001,2008 and 2015 was calculated.Through regression analysis,it was found that the node degree had a logarithmic relationship with the average length of node path,and the two parameters of the logarithmic relationship had linear evolutionary trace.Key word:China aviation network,complex network,node degree,average length of node path,logarithmic relationship,evolutionary trace. 展开更多
关键词 China aviation network complex network node degree average length of node path logarithmic relationship evolutionary trace.
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Small World Properties Generated by a New Algorithm Under Same Degree of All Nodes 被引量:8
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作者 LI Yong FANG Jin-Qing LIU Qiang LIANG Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期950-954,共5页
Based on the model of the same degree of all nodes we proposed before, a new algorithm, the so-called “spread all over vertices” (SAV) algorithm, is proposed for generating small-world properties from a regular ri... Based on the model of the same degree of all nodes we proposed before, a new algorithm, the so-called “spread all over vertices” (SAV) algorithm, is proposed for generating small-world properties from a regular ring lattices. During randomly rewiring connections the SAV is used to keep the unchanged number of links. Comparing the SAV algorithm with the Watts-Strogatz model and the “spread all over boundaries” algorithm, three methods can have the same topological properties of the small world networks. These results offer diverse formation of small world networks. It is helpful to the research of some applications for dynamics of mutual oscillator inside nodes and interacting automata associated with networks. 展开更多
关键词 small world network the same degree of all nodes in the network “spread all over vertices”algorithm average shortest path length average clustering coefficient
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Light trapping characteristics of glass substrate with hemisphere pit arrays in thin film Si solar cells 被引量:2
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作者 陈乐 王庆康 +2 位作者 王阳培华 黄堃 沈向前 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第4期16-21,共6页
In this paper, the light trapping characteristics of glass substrate with hemisphere pit (HP) arrays in thin film Si solar cells are theoretically studied via a numerical approach. It is found that the HP glass subs... In this paper, the light trapping characteristics of glass substrate with hemisphere pit (HP) arrays in thin film Si solar cells are theoretically studied via a numerical approach. It is found that the HP glass substrate has good antireflection properties. Its surface reflectance can be reduced by - 50% compared with planar glass. The HP arrays can make the unabsorbed light return to the absorbing layer of solar cells, and the ratio of second absorption approximately equals 30%. Thus, the glass substrate with the hemisphere pit arrays (HP glass) can effectively reduce the total reflectivity of a solar celt from 20% to 13%. The lip glass can also prolong the optical path length. The numerical results show that the total optical path length of the thin film Si solar cell covered with the HP glass increases from 2ω to 409. These results are basically consistent with the experimental results. 展开更多
关键词 numerical approach light trapping hemispherical pit (HP) optical path length solar cells
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MFPL:Multi-Frequency Phase Difference Combination Based Device-Free Localization 被引量:1
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作者 Zengshan Tian Weiqin Yang +2 位作者 Yue Jin Liangbo Xie Zhengwen Huang 《Computers, Materials & Continua》 SCIE EI 2020年第2期861-876,共16页
With the popularity of indoor wireless network,device-free indoor localization has attracted more and more attention.Unlike device-based localization where the target is required to carry an active transmitter,their f... With the popularity of indoor wireless network,device-free indoor localization has attracted more and more attention.Unlike device-based localization where the target is required to carry an active transmitter,their frequent signal scanning consumes a large amount of energy,which is inconvenient for devices with limited energy.In this work,we propose the MFPL,device-free localization(DFL)system based on WiFi distance measurement.First,we combine multi-subcarrier characteristic of Channel State Information(CSI)with classical Fresnel reflection model to get the linear relationship between the change of the length of reflection path and the subcarrier phase difference.Then we calculate the Fresnel phase difference between subcarrier pairs with different spacing from CSI amplitude time series.Finally,we get the change of the length of the reflection path caused by target moving to achieve distance measurement and localization.Using a combination of subcarriers with different spacing to achieve distance measurement effectively broadens the maximum unambiguous distance of the system.To solve the complex non-linear problem of the intersection of two elliptic equations,we introduce Newton's method to transform the non-linear problem into a linear one.The effectiveness of our approach is verified using commodity WiFi infrastructures.The experimental results show our method achieves a median error of 0.87 m in actual indoor environment. 展开更多
关键词 Indoor localization WiFi channel state information fresnel phase difference reflection path length
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An Ideal Assortative Network and Synchronization
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作者 DONG Cheng-Dong LIU Zeng-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期186-192,共7页
This paper proposes a novel complex network with assortative property based on multi-center networks. The average path length and clustering coefficient of the network are calculated, and the impact on the network top... This paper proposes a novel complex network with assortative property based on multi-center networks. The average path length and clustering coefficient of the network are calculated, and the impact on the network topology is investigated. A simple dynamic system established on the proposed network is used to analyze how the assortative property of the network affects synchronization. 展开更多
关键词 complex network assortative property average path length clustering coefficient SYNCHRONIZATION
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PATH PROBLEM SIMPLIFICATION WITH DESIRED BOUNDED LENGTHS IN ACYCLIC NETWORKS
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作者 Zhixiong Su Jianxun Qi Hanying Wei 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2015年第4期500-519,共20页
Path determination is a fundamental problem of operations research. Current solutions mainly focus on the shortest and longest paths. We consider a more generalized problem; specifically, we consider the path problem ... Path determination is a fundamental problem of operations research. Current solutions mainly focus on the shortest and longest paths. We consider a more generalized problem; specifically, we consider the path problem with desired bounded lengths (DBL path problem). This problem has extensive applications; however, this problem is much harder, especially for large-scale problems. An effective approach to this problem is equivalent simplification. We focus on simplifying the problem in acyclic networks and creating a path length model that simplifies relationships between various path lengths. Based on this model, we design polynomial algorithms to compute the shortest, longest, second shortest, and second longest paths that traverse any arc. Furthermore, we design a polynomial algorithm for the equivalent simplification of the is O(m), where m is the number of arcs. DBL path problem. The complexity of the algorithm 展开更多
关键词 Operations research path problem with desired bounded lengths equivalent simplification path length model acyclic network
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SFES: A scalable, fault-tolerant, efficient search scheme in a peer-to-peer network
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作者 李振武 杨舰 +1 位作者 史旭东 白英彩 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第4期452-460,共9页
This paper presents SFES: a scalable, fault-tolerant, efficient search scheme in a peer-to-peer network. The idea is based on the fact that data distribution in an information society has structured features. We desig... This paper presents SFES: a scalable, fault-tolerant, efficient search scheme in a peer-to-peer network. The idea is based on the fact that data distribution in an information society has structured features. We designed an algorithm to cluster peers that have similar interests. When receiving a query request, a peer will preferentially forward it to another peer which belongs to the same cluster and shares more similar interests. By this method, search efficiency will be remarkably improved and at the same time good resistance against peer failure (the ability to withstand peer failure) is reserved. Keyword partial-match is supported, too. 展开更多
关键词 peer-to-peer network CLUSTER OVERLAY STRUCTURED request path length
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Topological Properties of Fibonacci Networks
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作者 张静远 孙伟刚 +1 位作者 童丽艳 李常品 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第9期375-379,共5页
The Fibonacci numbers are the numbers defined by the linear recurrence equation, in which each subsequent number is the sum of the previous two. In this paper, we propose Fibonacci networks using Fibonacci numbers. Th... The Fibonacci numbers are the numbers defined by the linear recurrence equation, in which each subsequent number is the sum of the previous two. In this paper, we propose Fibonacci networks using Fibonacci numbers. The analyticai expressions involving degree distribution, average path lengh and mean first passage time are obtained. This kind of networks exhibits the smail-world characteristic and follows the exponential distribution. Our proposed models would provide the vaiuable insights into the deterministicaily delayed growing networks. 展开更多
关键词 complex networks Fibonacci numbers average path length random walks
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Research of Scalability of the Belt-Type Sensor Networks
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作者 徐志广 朱磊基 +1 位作者 施玉松 姜华 《Journal of Shanghai Jiaotong university(Science)》 EI 2012年第2期237-240,共4页
For the large-scale application requirements of the belt-type networks,the mathematical modeling as well as quantitative analysis for the scalability of the network based on average path length is completed in this pa... For the large-scale application requirements of the belt-type networks,the mathematical modeling as well as quantitative analysis for the scalability of the network based on average path length is completed in this paper,and the theorem for the scale scalability of the belt-type networks is derived.The theorem provides a calculation formula for the upper limit of node scale theory of the belt-type networks and a calculation formula for the upper limit of single node load theory. 展开更多
关键词 belt-type sensor networks average path length SCALABILITY
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APL-based flexibility analysis of manufacturing grid
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作者 刘丽兰 孙雪华 +1 位作者 蔡红霞 柴建飞 《Journal of Shanghai University(English Edition)》 2009年第5期352-355,共4页
With the characteristics of diversity, randomness, concurrency and decomposability, tasks in manufacturing field are very complicated, and so manufacturing grid (MG) should have considerable flexibility to deal with t... With the characteristics of diversity, randomness, concurrency and decomposability, tasks in manufacturing field are very complicated, and so manufacturing grid (MG) should have considerable flexibility to deal with this problem. With the definition of node and arc, MG structure is converted into a small-world network. Given construction cost constraint, the problem of shortest task waiting time is transformed into the constrained optimization problem, and a corresponding ?exibility analysis model based on average path length (APL) is proposed, and the premise of arc-length and node-distance are defined. The results of application example show that the analysis model is effiective. 展开更多
关键词 manufacturing grid (MG) complex network average path length (APL) flexibility analysis model
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QKD system with fast active optical path length compensation
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作者 Byung Kwon Park Min Soo Lee +3 位作者 Min Ki Woo Yong-Su Kim Sang-Wook Han Sung Moon 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2017年第6期1-7,共7页
We develop a quantum key distribution (QKD) system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a plug-and-play QKD ... We develop a quantum key distribution (QKD) system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a plug-and-play QKD system. The system monitors changes in key rates and controls it is own operation automatically. The system achieves its optimal performance within three seconds of operation, which includes a sifted key rate of 5.5 kbps and a quantum bit error rate of less than 2% after an abrupt temperature variation along the 25 km quantum channel. The system also operates well over a 24 h period while completing more than 60 active optical path length compensations. 展开更多
关键词 quantum key distribution optical path length compensation plug and play field programmable gate array
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On the complexity of average path length for biological networks and patterns
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作者 Waqar Asif Hassaan Khaliq Qureshi +1 位作者 Adnan Iqbal Muttukrishnan Rajarajan 《International Journal of Biomathematics》 2014年第4期51-61,共11页
Path length calculation is a frequent requirement in studies related to graph theoretic problems such as genetics. Standard method to calculate average path length (APL) of a graph requires traversing all nodes in t... Path length calculation is a frequent requirement in studies related to graph theoretic problems such as genetics. Standard method to calculate average path length (APL) of a graph requires traversing all nodes in the graph repeatedly, which is computationally expensive for graphs containing large number of nodes. We propose a novel method to calculate APL for graphs commonly required in the studies of genetics. The proposed method is computationally less expensive and less time-consuming compared to standard method. 展开更多
关键词 REDUCTIONISM average path length protein protein interaction.
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Retinal thermal deformations measured with phase-sensitive optical coherence tomography in vivo 被引量:1
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作者 Yueming Zhuo Mohajeet Bhuckory +5 位作者 Huakun Li Junya Hattori Davis Pham-Howard David Veysset Tong Ling Daniel Palanker 《Light: Science & Applications》 2025年第5期1459-1468,共10页
Controlling the tissue temperature rise during retinal laser therapy is essential for predictable outcomes,especially at non-damaging settings.We demonstrate a method for determining the temperature rise in the retina... Controlling the tissue temperature rise during retinal laser therapy is essential for predictable outcomes,especially at non-damaging settings.We demonstrate a method for determining the temperature rise in the retina using phasesensitive optical coherence tomography(pOCT)in vivo.Measurements based on the thermally induced optical path length changes(ΔOPL)in the retina during a 10-ms laser pulse allow detection of the temperature rise with a precision less than 1℃,which is sufficient for calibration of the laser power for patient-specific non-damaging therapy.We observed a significant difference in confinement of the retinal deformations between the normal and the degenerate retina:in wild-type rats,thermal deformations are localized between the retinal pigment epithelium(RPE)and the photoreceptors’inner segments(IS),as opposed to a deep penetration of the deformations into the inner retinal layers in the degenerate retina.This implies the presence of a structural component within healthy photoreceptors that dampens the tissue expansion induced by the laser heating of the RPE and pigmented choroid.We hypothesize that the thin and soft cilium connecting the inner and outer segments(IS,OS)of photoreceptors may absorb the deformations of the OS and thereby preclude the tissue expansion further inward.Striking difference in the confinement of the retinal deformations induced by a laser pulse in healthy and degenerate retina may be used as a biomechanical diagnostic tool for the characterization of photoreceptors degeneration. 展开更多
关键词 detection temperature rise tissue temperature rise retinal thermal deformations phase sensitive optical coherence tomography calibration la determining temperature rise retinal laser therapy thermally induced optical path length changes opl
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