最新刊期
卷 33 ， 期 1 ， 2017
- 摘要：When a large number of concurrent requests are allocated,the load scheduling mechanism is to achieve the load balancing of nodes in the network by minimizing the response time and maximizing the utilization ratio of nodes.In the load balancing algorithm based on genetic algorithm,the fitness function is designed to have an important influence on the load balancing efficiency.A service cluster load balancing method based on mean-variance was proposed to optimize the fitness function.The investment portfolio selection model mean-variance was used to minimize the response time,which was used to get the weight of each server's resource utilization,so as to obtain the optimal allocation combination.This method improves the accuracy and efficiency of the fitness function.Compared with other models in different service environment,the simulation results show that the load balancing algorithm makes the service cluster get a better balance performance in terms of node utilization and response time.关键词：load balancing;mean-variance model;genetic algorithm;load scheduling780|1704|0更新时间：2024-06-05
- 摘要：Aiming at the shortcomings of heavy workload in the off-line phase,limited positioning accuracy and poor robustness of indoor location fingerprint positioning technology,an improved fingerprint matching algorithm based on linear interpolation was proposed.Compared with the traditional location fingerprint positioning technology,it reduced the overall workload as well as the bad effects caused by muti-path effect.At last,a lab scene was set up to test the positioning performance of this algorithm.It is shown by the test that the average positioning accuracy of this algorithm has been improved by 34.25% compared with that of WKNN method,and the positioning accuracy error ratio of most points to be test is within 0.4 m,the positioning accuracy,robustness and adaptability in environment change were demonstrated.关键词：indoor location;location fingerprint;weighted K-nearest neighbor;principal component analysis;linear interpolation995|1976|0更新时间：2024-06-05
- 摘要：A hybrid cooperative jamming protocol was proposed to improve secrecy capacity for the full-duplex relay system with a passive eavesdropper,which chose the relay-and-source-based cooperative jamming (RSCJ) protocol or the relay-and-destination-based cooperative jamming (RDCJ) protocol according to the channel state information.Taking the self-interference at both the relay and the receiver into consideration,a protocol selection strategy was proposed and the expressions of secrecy outage probability of the system with RSCJ or RDCJ were derived.Simulation results show that the secrecy performance is significantly improved when the proposed hybrid cooperative jamming protocol is applied.Compared to the conventional transmission scheme,the proposed protocol has significant safety performance advantages.关键词：physical layer security;cooperative jamming;full-duplex;relay system;secrecy outage probability734|986|0更新时间：2024-06-05
- 摘要：Community structure is one of the topological characteristics of social network.It is an important research topic in social network research to explore the structure of community,detect and predict the change of community structure.The evolution of dynamic community was discussed from time slicing processing and dynamic increment strategies.The time slice processing strategy introduced the comparative evolution of the time slice,the clustering evolution of the time slice,and the fusion evolution of the time slice.The dynamic increment strategy described the dynamic evolution of the core community,the dynamic evolution of the cluster and the dynamic evolution of the index.Finally,the framework of community evolution prediction was summarized.关键词：dynamic community mining;dynamic community evolution;dynamic community evolution prediction569|1596|0更新时间：2024-06-05
- 摘要：The fifth generation (5G) mobile communication technology has the characteristics of high speed and large bandwidth,which makes the fading of radio signal in time domain and frequency domain more obviously.With the increase of differential values statistical step and the spatial sampling interval,the channel estimation method based on the differential probability can't track the deep fading area and the peak area was over-tacked.In view of the above problems,a channel estimation method based on quadratic differentials probability was proposed.Firstly,the valley point and peak point of the fading curve were found.Then,the estimated differential values of deep fading area and peak area were improved by quadratic differential probability.Finally,the estimated gains were obtained by the difference operation.Simulation results show that,this method can improve the whole tracking performance effectively and reduce the tracking error.关键词：5G;mobile radio channel;channel estimation;differentials probability;quadratic differentials419|1459|0更新时间：2024-06-05
- 摘要：Based on the existing threshold denoising algorithm,a threshold denoising algorithm based on the new symbolic function was proposed.The new threshold function has advantages of continuous guidance,small deviation of wavelet coefficient,strong threshold adaptability and so on.It not only preserved the low-frequency wavelet coefficients,but also filtered the noise coefficients in the high-frequency coefficients effectively,so that the reconstructed image was closer to the original image.The simulation results of Bridge image,Lena image and B-mode Fetus image with Gaussian white noise show that the visual effect of both the new threshold function and the quantitative indicators PSNR and MSE are better than the existing threshold image denoising algorithm.The edge and detail information can be better protected,have no obvious oscillation,the image is smoother and even,and the method has good stubbornness under the background of complex noise.关键词：sign function;wavelet threshold;denoising;robustness441|1533|0更新时间：2024-06-05
- 摘要：In order to solve the problem of the communication performance of degradation,which caused by multi-intersections in city environment and no sensitivity to individual node movements,an intersection-based geographical perception routing protocol in vehicular Ad Hoc network was proposed.The network gateways select road intersections to form the backbone of the route,ensuring a high probability of communication and meeting delay and bit error rate requirements.Mathematical formula of the average delay and the average number of hops were obtained on the basis of a two-way road model.Simulation results show that the transmission delay of IGPR is smaller,the number of hops of IGPR is less,and the communication performance of IGPR is better compared with the FRGR protocols and VRR protocols.关键词：vehicular Ad Hoc network;routing protocol;average delay;average number of hops343|1175|0更新时间：2024-06-05
- 摘要：Under the background of profound contradiction between supply and demand of radio spectrum resource,the American and European countries are speeding up the research of efficient spectrum management policy and application technology.USA puts forward the concept of spectrum super-highway for the first time.On the basis of domestic and abroad research achievements in spectrum management,the basic meanings and characteristics of our state's spectrum super-highway were defined,its main application fields were indicated,and then the system function architecture,network structure,and the corresponding system working procedures were proposed.In addition,related suggestions for our state's spectrum super-highway system establishment were put forward,and outlook of issues in the process of construction was also provided.关键词：spectrum super-highway;system architecture;spectrum sharing;spectrum handoff;spectrum market381|954|0更新时间：2024-06-05
- 摘要：Conditional random field (CRF) is a powerful model for image labeling,it is particularly well-suited to model local interactions among adjacent regions (e.g.superpixels).However,CRF doesn't consider the global constraint of objects.The overall shape of the object is used as a global constraint,the ShapeBM can be taken advantage of modeling the global shape of object,and then a new labeling model that combined the above two types of models was presented.The combination of CRF and ShapeBM was based on the superpixels,through the pooling technology was wed to establish the corresponding relationship between the CRF superpixel layer and the ShapeBM input layer.It enhanced the effectiveness of the combination of CRF and ShapeBM and improved the accuracy of the labeling.The experiments on the Penn-Fudan Pedestrians dataset and Caltech-UCSD Birds 200 dataset demonstrate that the model is more effective and efficient than others.关键词：CRF;ShapeBM;join model;superpixels;image labeling371|824|0更新时间：2024-06-05
- 摘要：Concerning that the correlation degree of the existing methods of blog screen and mining is loose and the information retrieval of the methods is deficient,a method based on temporal feature and hybrid search method was proposed.Considering the user reviews are important sources of evidence combination,the average number of reviews for blogs,the sources of BM25 relevance scores,the longest blog BM25 scores and time range between the latest related blog paper and the oldest related blog paper are being as the temporal feature sets.In addition,considering local search advantage of linear search(LS) and global search advantage of differential evolution(DE),the two kinds of information search methods were combined.BlogS06 data set was used in the experiment which was consists of blog home pages,XML source files and its blog portal pages,it was used for TREC 2007 and TREC 2008 blog mining experiments.Experimental results show that the proposed method can obtain satisfactory results in terms of running time and effectiveness.关键词：blog screening and mining;temporal feature;linear search;differential evolution;big data;BM25284|1013|0更新时间：2024-06-05
- 摘要：With the widespread availability of cell-phone recording devices and the availability of various powerful and easy-to-use digital media editing software,source cell-phone identification has become a hot topic in multimedia forensics.A novel cell-phone identification method was proposed based on the recorded speech.Firstly,device self-noise (DSN) was considered as the fingerprint of the cell-phone and estimated from the silent segments of the speech.Then,the mean of the noise's spectrum was extracted as the identification.Principal components analysis (PCA) was applied to reduce the feature dimension.Support vector machine (SVM) was adopted as the classifier to determine the source of the detecting speech.Twenty-four popular models of the cell-phones were evaluated in the experiment.The experimental results show that the average identification accuracy and recall of the method can reach up to 99.24% and demonstrate that the self-noise feature has more superior performance than the MFCC feature.关键词：multimedia forensics;cell-phone origin identification;self-noise;spectral feature489|1468|0更新时间：2024-06-05
research and development
- 摘要：Cooperative spectrum sensing (CSS) improves the reliability of spectrum sensing,however,it is susceptible to spectrum sensing data falsification (SSDF) due to the fusion mechanism.To insight into the current research and development trend of defense strategy against the SSDF attack,several typical distributed strategies were concluded and the types of distributed algorithms were analyzed in several aspects.Finally,the future research of SSDF distributed defense strategy was prospected based on the problems found in the current research.关键词：cognitive radio;spectrum sensing data falsification;cooperative spectrum sensing429|743|0更新时间：2024-06-05
- 摘要：To deal with the new situation of satellite interference and solve the problem of satellite interference effectively,new techniques and methods of mitigating satellite interference were studied.The technology and development trend of satellite interference geolocation were summarized.The method of applying unmanned aerial vehicle assisted to find the ground interfering source was proposed,and it was introduced that using carrier identification (CID) standard to determine the satellite interference source.The implementation method of satellite terminal authentication and data sharing strategy to combat interference was given.It shows that multi-party cooperation and data sharing may be the most effective way to solve the problem of satellite interference.关键词：satellite interference;unmanned aerial vehicle;interference geolocation;carrier identification;data sharing;terminal authentication630|2264|0更新时间：2024-06-05
Overview
- 摘要：With the spreading of broadband acceleration strategy and the quick development of streaming media such as IPTV/OTT,a higher quality of experience on the services of telecom operators need to be satisfied.The current maintenance system and method is operating on different levels and segments,which is lack of interactive functions and cooperation.Therefore,a new method is required to satisfy the network maintenance work in the new developing environment.A new method was proposed to construct the intelligent maintenance system of the intensive broadband service.With this method,it is able to achieve the end-to-end quality monitoring and automatic self-diagnosis functions.The method will benefit the services of telecom operators and will improve the efficiency and intelligence of telecom operators.关键词：broadband network;quality monitoring;automatic self-diagnosis;intelligent maintenance416|1391|0更新时间：2024-06-05
- 摘要：The related standards of fiber to the home engineering were introduced.The connection mode and transmission requirements of fiber link on the user side were described.According to the test experience accumulated in recent years,the problems and causes found in optical fiber link acceptance test were analyzed and the suggestions on how to guarantee the link quality were also put forward.关键词：fiber to the home;acceptance test;attenuation of optical fiber line350|1365|0更新时间：2024-06-05
- 摘要：The rapid development of big data technology provides fast mass data processing method for operators' traditional businesses,such as network planning and optimization,but also laid the data foundation for new businesses,such as credit,personalized recommendations,internet services.It is important to the development of the industry.The big data processing cutting-edge technology was studied,relative engineering experience and key issues were introduced,reference for other researcher was provided.关键词：big data processing;network planning;network optimization521|1641|0更新时间：2024-06-05
- 摘要：ETL is a very important step in the implementation process of data warehouse.A good ETL flow is important,which can effectively process the telecom big data and improve the acquisition efficiency of the operation platform.Firstly,the main data content of the big data platform was expounded.Secondly,in order to improve the efficiency of massive data collection,Hadoop and Oracle mashup solution was suggested.Subsequently,a dynamic triggered ETL scheduling flow and algorithm was proposed.Compared with timer start ETL scheduling method,it could effectively shorten waiting time and avoid the phenomenon of resources to seize and congestion.Finally,according to the running log of Hadoop platform and Oracle database,the relationship between acquisition efficiency and data quantity was analyzed comparatively.Furthermore,practice result shows that the hybrid data structure of the big data platform complement each other and can effectively enhance the timeliness of data collection and access better application effect.关键词：big data;ETL;Hadoop;scheduling process;mashup architecture853|1558|0更新时间：2024-06-05
- 摘要：Current RF specification restrains the wireless meter reading system (WMRS) working in 470～510 MHz band.It is incapable of meeting new communication speed and coverage requirements of power network.Under the premise of ensuring that prior used communication systems in adjacent band work without interference,how to modify the related RF specification to improve communication ability of WMRS is one of the problems to be solved at present.Firstly,the domestic frequency spectrum allocation in 450～566 MHz band was analyzed.Then,based on RF parameters of 3 kinds of WMRS from State Grid and deterministic computation and ray tracing simulation method,the interference coexistence between the WMRS and adjacent communication systems,which including broadcast television system,CDMA450 system,railway train dispatching system and FDD-LTE system was studied.At last,some suggestions for revision of relevant RF specifications were obtained.关键词：470～510 MHz;wireless meter reading system;interference coexistence;modification suggestion;RF requirement681|2130|0更新时间：2024-06-05
- 摘要：The construction scale of optical broadband network brings the massive construction of the access network optic fibers,and the key point is the operation,the maintenance and the management of the network after the large construction,thus it is very important to use highly efficient detection methods and related flexible application methods.Based on the analysis of ODN,the capability of OTDR applied in ODN was analyzed,and the characteristics of ODN key events in the OTDR test was focused,meanwhile according to OTDR detection shortcomings,relevant OTDR application schemes were suggested.关键词：ODN;OTDR;return loss;attenuation event387|1275|0更新时间：2024-06-05
- 摘要：In the communication engineering practice,it often needs to estimate the unknown samples which are missing with the limited samples,then the interpolation operation is needed.Based on the research of cubic spline interpolation,the validity was given in communication engineering applications of the cubic spline interpolation by the experimental results on free space loss calculation,feeder insertion loss estimation,correlative interferometer.关键词：cubic spline interpolation;free-space transmission loss;feeder insertion loss;correlation interferometer direction finding571|1691|0更新时间：2024-06-05
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