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Bidirectional Background Modeling for Video Surveillance 被引量:2
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作者 Chih-Yang Lin Yung-Chen Chou 《Journal of Electronic Science and Technology》 CAS 2012年第3期232-237,共6页
Traditional background model methods often require complicated computations, and are sensitive to illumination and shadow. In this paper, we propose a block-based background modeling method, and use our proposed metho... Traditional background model methods often require complicated computations, and are sensitive to illumination and shadow. In this paper, we propose a block-based background modeling method, and use our proposed method to combine color and texture characteristics. Suppression and relaxation are the two key strategies to resist illumination changes and shadow disturbance. The proposed method is quite efficient and is capable of resisting illumination changes. Experimental results show that our method is suitable for real-word scenes and real-time applications. 展开更多
关键词 background modeling Gaussianmixture modeling motion detection.
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Video Frame’s Background Modeling: Reviewing the Techniques 被引量:4
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作者 Hamid Hassanpour Mehdi Sedighi Ali Reza Manashty 《Journal of Signal and Information Processing》 2011年第2期72-78,共7页
Background modeling is a technique for extracting moving objects in video frames. This technique can be used in ma-chine vision applications, such as video frame compression and monitoring. To model the background in ... Background modeling is a technique for extracting moving objects in video frames. This technique can be used in ma-chine vision applications, such as video frame compression and monitoring. To model the background in video frames, initially, a model of scene background is constructed, then the current frame is subtracted from the background. Even-tually, the difference determines the moving objects. This paper evaluates a number of existing background modeling techniques in term of accuracy, speed and memory requirement. 展开更多
关键词 background modeling MOVING OBJECT
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Modeling and Generating Realistic Background Traffic by Hybrid Approach 被引量:2
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作者 QIAN Yaguan GUAN Xiaohui +1 位作者 JIANG Ming CEN Gang 《China Communications》 SCIE CSCD 2015年第10期147-157,共11页
One of the key challenges in largescale network simulation is the huge computation demand in fine-grained traffic simulation.Apart from using high-performance computing facilities and parallelism techniques,an alterna... One of the key challenges in largescale network simulation is the huge computation demand in fine-grained traffic simulation.Apart from using high-performance computing facilities and parallelism techniques,an alternative is to replace the background traffic by simplified abstract models such as fluid flows.This paper suggests a hybrid modeling approach for background traffic,which combines ON/OFF model with TCP activities.The ON/OFF model is to characterize the application activities,and the ordinary differential equations(ODEs) based on fluid flows is to describe the TCP congestion avoidance functionality.The apparent merits of this approach are(1) to accurately capture the traffic self-similarity at source level,(2) properly reflect the network dynamics,and(3) efficiently decrease the computational complexity.The experimental results show that the approach perfectly makes a proper trade-off between accuracy and complexity in background traffic simulation. 展开更多
关键词 network simulation background traffic ON/OFF models fluid flows self-similarity
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Background modeling methods in video analysis: A review and comparative evaluation 被引量:5
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作者 Yong Xu Jixiang Dong +1 位作者 Bob Zhang Daoyun Xu 《CAAI Transactions on Intelligence Technology》 2016年第1期43-60,共18页
Foreground detection methods can be applied to efficiently distinguish foreground objects including moving or static objects from back- ground which is very important in the application of video analysis, especially v... Foreground detection methods can be applied to efficiently distinguish foreground objects including moving or static objects from back- ground which is very important in the application of video analysis, especially video surveillance. An excellent background model can obtain a good foreground detection results. A lot of background modeling methods had been proposed, but few comprehensive evaluations of them are available. These methods suffer from various challenges such as illumination changes and dynamic background. This paper first analyzed advantages and disadvantages of various background modeling methods in video analysis applications and then compared their performance in terms of quality and the computational cost. The Change detection.Net (CDnet2014) dataset and another video dataset with different envi- ronmental conditions (indoor, outdoor, snow) were used to test each method. The experimental results sufficiently demonstrated the strengths and drawbacks of traditional and recently proposed state-of-the-art background modeling methods. This work is helpful for both researchers and engineering practitioners. Codes of background modeling methods evaluated in this paper are available atwww.yongxu.org/lunwen.html. 展开更多
关键词 background modeling Video analysis Comprehensive evaluation
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Diversity Sampling Based Kernel Density Estimation for Background Modeling
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作者 毛燕芬 施鹏飞 《Journal of Shanghai University(English Edition)》 CAS 2005年第6期506-509,共4页
A novel diversity-sampling based nonparametric multi-modal background model is proposed. Using the samples having more popular and various intensity values in the training sequence, a nonparametric model is built for ... A novel diversity-sampling based nonparametric multi-modal background model is proposed. Using the samples having more popular and various intensity values in the training sequence, a nonparametric model is built for background subtraction. According to the related intensifies, different weights are given to the distinct samples in kernel density estimation. This avoids repeated computation using all samples, and makes computation more efficient in the evaluation phase. Experimental results show the validity of the diversity- sampling scheme and robustness of the proposed model in moving objects segmentation. The proposed algorithm can be used in outdoor surveillance systems. 展开更多
关键词 background subtraction diversity sampling kernel density estimation multi-modal background model
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A numerical model study on multi-species harmful algal blooms coupled with background ecological fields 被引量:2
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作者 WANG Qing ZHU Liangsheng WANG Dongxiao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第8期95-105,共11页
Based on systematized physical, chemical, and biological modules, a multi-species harmful algal bloom (HAB) model coupled with background ecological fields was established. This model schematically embod-ied that HA... Based on systematized physical, chemical, and biological modules, a multi-species harmful algal bloom (HAB) model coupled with background ecological fields was established. This model schematically embod-ied that HAB causative algal species and the background ecological system, quantified as total biomass, were significantly different in terms of the chemical and biological processes during a HAB while the inter-action between the two was present. The model also included a competition and interaction mechanism between the HAB algal species or populations. The Droop equation was optimized by considering tempera-ture, salinity, and suspended material impact factors in the parameterization of algal growth rate with the nutrient threshold. Two HAB processes in the springs of 2004 and 2005 were simulated using this model. Both simulation results showed consistent trends with corresponding HAB processes observed in the East China Sea, which indicated the rationality of the model. This study made certain progress in modeling HABs, which has great application potential for HAB diagnosis, prediction, and prevention. 展开更多
关键词 background ecological fields MULTI-SPECIES harmful algal bloom numerical model
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3-D finite element modeling for evolution of stress field and interaction among strong earthquakes in Sichuan-Yunnan region 被引量:3
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作者 CHEN Hua-ran(陈化然) +11 位作者 CHEN Lian-wang(陈连旺) MA Hong-sheng(马宏生) LI Yi-qun(李轶群) ZHANG Jie-qing(张杰卿) HE Qiao-yun(何巧云) WANG Jian-guo(王建国) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第6期625-634,共10页
Based on the latest achievement about activities of geological structure, a 3-D finite-element model containing four layers of upper crust, lower crust (two layers) and upper mantle is established in the paper. By rep... Based on the latest achievement about activities of geological structure, a 3-D finite-element model containing four layers of upper crust, lower crust (two layers) and upper mantle is established in the paper. By repeated tests and revisions, the boundary conditions of the model are determined. And then the background stress field, the stress field caused by fault creep and the stress field triggered by strong earthquake in Sichuan-Yunnan region, as well as their dynamic variations are calculated. The results indicate that the latter earthquake often occurs in the area with positive Coulomb rupture stress change associated with the former one, the former earthquake has a triggering effect on the latter one to a certain extent, and strong earthquake often occur in groups under the background of high stress, which is of great significance for distinguishing seismic anomalies, as well as for improving the level of earthquake prediction. 展开更多
关键词 D finite element model background stress field stress field caused by fault creep stress field triggered by strong earthquake
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Moving object detection method based on complementary multi resolution background models 被引量:2
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作者 屠礼芬 仲思东 彭祺 《Journal of Central South University》 SCIE EI CAS 2014年第6期2306-2314,共9页
A novel moving object detection method was proposed in order to adapt the difficulties caused by intermittent object motion,thermal and dynamic background sequences.Two groups of complementary Gaussian mixture models ... A novel moving object detection method was proposed in order to adapt the difficulties caused by intermittent object motion,thermal and dynamic background sequences.Two groups of complementary Gaussian mixture models were used.The ghost and real static object could be classified by comparing the similarity of the edge images further.In each group,the multi resolution Gaussian mixture models were used and dual thresholds were applied in every resolution in order to get a complete object mask without much noise.The computational color model was also used to depress illustration variations and light shadows.The proposed method was verified by the public test sequences provided by the IEEE Change Detection Workshop and compared with three state-of-the-art methods.Experimental results demonstrate that the proposed method is better than others for all of the evaluation parameters in intermittent object motion sequences.Four and two in the seven evaluation parameters are better than the others in thermal and dynamic background sequences,respectively.The proposed method shows a relatively good performance,especially for the intermittent object motion sequences. 展开更多
关键词 moving object detection complementary Gaussian mixture models intermittent object motion thermal and dynamic background
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On Segmentation of Moving Objects by Integrating PCA Method with the Adaptive Background Model 被引量:1
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作者 Noureldaim Emadeldeen Mohammed Jedra Noureldeen Zahid 《Journal of Signal and Information Processing》 2012年第3期387-393,共7页
Tracking and segmentation of moving objects are suffering from many problems including those caused by elimination changes, noise and shadows. A modified algorithm for the adaptive background model is proposed by link... Tracking and segmentation of moving objects are suffering from many problems including those caused by elimination changes, noise and shadows. A modified algorithm for the adaptive background model is proposed by linking Gaussian mixture model with the method of principal component analysis PCA. This approach utilizes the advantage of the PCA method in providing the projections that capture the most relevant pixels for segmentation within the background models. We report the update on both the parameters of the modified method and that of the Gaussian mixture model. The obtained results show the relatively outperform of the integrated method. 展开更多
关键词 PIXELS GAUSSIAN MIXTURE model PRINCIPLE Component Analysis background model Noise Process Segmentation
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The Dynamic Location Model to Consider Background Traffic
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作者 Nahry Yusuf Sutanto Soehodho 《Journal of Transportation Technologies》 2012年第1期41-49,共9页
This study concerns to the determination of location of freight distribution warehouses. It is part of a series of research projects on a distribution system we developed to deal with cases in a public service obligat... This study concerns to the determination of location of freight distribution warehouses. It is part of a series of research projects on a distribution system we developed to deal with cases in a public service obligation state-owned company (PSO-SOC). This current research is characterized by the consideration of background traffic of the entire time period of planning rather than one certain time target on location model. It is aimed that the location decision to be more applicable and accommodative to the dynamic of the traffic condition. Once the decision is implemented, it will give the best outcome for the entire time period, not only for the initial time, end time or certain time of time period. A heuristic approach is proposed to simplify complexity of the model and network representation technique is applied to solve the model. A hyphotetical example is discussed to illustrate the mechanism of finding the optimal solution in term of both its objective function and applicability. 展开更多
关键词 background TRAFFIC LOCATION model FREIGHT DISTRIBUTION
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Research on Korf Ball Athletes Selecting Model under the Background of High Level Athletes Data Guidance
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作者 Lujun Li 《International Journal of Technology Management》 2016年第5期55-57,共3页
In this paper, we conduct research on the Korf ball athlete basic selecting model under the background of high level athlete data guidance. Athletes selecting closely related to the ultimate goal of training for many ... In this paper, we conduct research on the Korf ball athlete basic selecting model under the background of high level athlete data guidance. Athletes selecting closely related to the ultimate goal of training for many years. So, naturally, great athletes become references, the structure model of the excellent athlete competitive ability become athletes selecting targeting. Based on abundant literature, discusses the selection of the targeting of athletes, in an effort to at the same time, the rich athletes selecting theory provides a new perspective for the material practice. Our paper integrates the basic information of the high level athlete data to construct the novel paradigm for further promotion. 展开更多
关键词 Korf BALL High Level DATA GUIDANCE Selecting model General background
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Optimal Insurance with Background Risk under the Ambiguity and Belief Heterogeneity Structure
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作者 Xiaohan Wang 《Journal of Applied Mathematics and Physics》 2024年第6期2160-2171,共12页
In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal i... In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal insurance contract when maxing the insured’s expected utility of his/her remaining wealth under the smooth ambiguity model and the heterogeneous belief form satisfying the MHR condition. We calculate the insurance premium by using generalized Wang’s premium and also introduce a series of stochastic orders proposed by [1] to describe the relationships among the insurable risk, background risk and ambiguity parameter. We obtain the deductible insurance is the optimal insurance while they meet specific dependence structures. 展开更多
关键词 Optimal Insurance Monotone Hazard Ratio Order Smooth Ambiguity model background Risk Belief Heterogeneity Structure
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Adaptive moving target detection algorithm based on Gaussian mixture model 被引量:1
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作者 杨欣 刘加 +1 位作者 费树岷 周大可 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期379-383,共5页
In order to enhance the reliability of the moving target detection, an adaptive moving target detection algorithm based on the Gaussian mixture model is proposed. This algorithm employs Gaussian mixture distributions ... In order to enhance the reliability of the moving target detection, an adaptive moving target detection algorithm based on the Gaussian mixture model is proposed. This algorithm employs Gaussian mixture distributions in modeling the background of each pixel. As a result, the number of Gaussian distributions is not fixed but adaptively changes with the change of the pixel value frequency. The pixels of the difference image are divided into two parts according to their values. Then the two parts are separately segmented by the adaptive threshold, and finally the foreground image is obtained. The shadow elimination method based on morphological reconstruction is introduced to improve the performance of foreground image's segmentation. Experimental results show that the proposed algorithm can quickly and accurately build the background model and it is more robust in different real scenes. 展开更多
关键词 moving target detection Gaussian mixture model background subtraction adaptive method
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PYRAMIDAL MULTIPHASE LEVEL SET FRAMEWORK FOR BRAIN TUMOR DETECTION USING GENERALIZED TECHNIQUE OF PAINTING BACKGROUND 被引量:1
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作者 郑罡 王惠南 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期36-42,共7页
The pyramidal multiphase level set framework (PMLSF) based on the technique of painting background (TPBG) and the Chan-Vese model can detect multiple objects on a given image. However, the boundaries of the sub-ob... The pyramidal multiphase level set framework (PMLSF) based on the technique of painting background (TPBG) and the Chan-Vese model can detect multiple objects on a given image. However, the boundaries of the sub-object obtained by PMLSF-TPBG are not variable since a specialcolor parameter is used in TPBG. To solve the problem, a new technique utilizing a varying parameter is proposed to ensure that PMLSF is effective for the detection of the desired boundaries of the sub-object. The interval of the variable color parameter is proved and the effects of the parameter are also discussed. Experimental results for the brain tumor detection show that different boundaries of the brain tumors can be detected with different color parameters. It is especially useful for clinical diagnoses. 展开更多
关键词 active contour model level set multiphase technique of painting background
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Adaptive learning algorithm based on mixture Gaussian background 被引量:9
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作者 Zha Yufei Bi Duyan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期369-376,共8页
The key problem of the adaptive mixture background model is that the parameters can adaptively change according to the input data. To address the problem, a new method is proposed. Firstly, the recursive equations are... The key problem of the adaptive mixture background model is that the parameters can adaptively change according to the input data. To address the problem, a new method is proposed. Firstly, the recursive equations are inferred based on the maximum likelihood rule. Secondly, the forgetting factor and learning rate factor are redefined, and their still more general formulations are obtained by analyzing their practical functions. Lastly, the convergence of the proposed algorithm is proved to enable the estimation converge to a local maximum of the data likelihood function according to the stochastic approximation theory. The experiments show that the proposed learning algorithm excels the formers both in converging rate and accuracy. 展开更多
关键词 Mixture Gaussian model background model Learning algorithm.
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Robust background subtraction in traffic video sequence 被引量:6
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作者 高韬 刘正光 +3 位作者 岳士弘 张军 梅建强 高文春 《Journal of Central South University》 SCIE EI CAS 2010年第1期187-195,共9页
For intelligent transportation surveillance, a novel background model based on Mart wavelet kernel and a background subtraction technique based on binary discrete wavelet transforms were introduced. The background mod... For intelligent transportation surveillance, a novel background model based on Mart wavelet kernel and a background subtraction technique based on binary discrete wavelet transforms were introduced. The background model kept a sample of intensity values for each pixel in the image and used this sample to estimate the probability density function of the pixel intensity. The density function was estimated using a new Marr wavelet kernel density estimation technique. Since this approach was quite general, the model could approximate any distribution for the pixel intensity without any assumptions about the underlying distribution shape. The background and current frame were transformed in the binary discrete wavelet domain, and background subtraction was performed in each sub-band. After obtaining the foreground, shadow was eliminated by an edge detection method. Experimental results show that the proposed method produces good results with much lower computational complexity and effectively extracts the moving objects with accuracy ratio higher than 90%, indicating that the proposed method is an effective algorithm for intelligent transportation system. 展开更多
关键词 background modeling background subtraction Marr wavelet binary discrete wavelet transform shadow elimination
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Ocean Data Assimilation with Background Error Covariance Derived from OGCM Outputs 被引量:3
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作者 符伟伟 周广庆 王会军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第2期181-192,共12页
The background error covariance plays an important role in modern data assimilation and analysis systems by determining the spatial spreading of information in the data. A novel method based on model output is propose... The background error covariance plays an important role in modern data assimilation and analysis systems by determining the spatial spreading of information in the data. A novel method based on model output is proposed to estimate background error covariance for use in Optimum Interpolation. At every model level, anisotropic correlation scales are obtained that give a more detailed description of the spatial correlation structure. Furthermore, the impact of the background field itself is included in the background error covariance. The methodology of the estimation is presented and the structure of the covariance is examined. The results of 20-year assimilation experiments are compared with observations from TOGA-TAO (The Tropical Ocean-Global Atmosphere-Tropical Atmosphere Ocean) array and other analysis data. 展开更多
关键词 data assimilation background error model output COVARIANCE
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Improvement and application of GM(1,1) model based on multivariable dynamic optimization 被引量:14
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作者 WANG Yuhong LU Jie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期593-601,共9页
For the classical GM(1,1)model,the prediction accuracy is not high,and the optimization of the initial and background values is one-sided.In this paper,the Lagrange mean value theorem is used to construct the backgrou... For the classical GM(1,1)model,the prediction accuracy is not high,and the optimization of the initial and background values is one-sided.In this paper,the Lagrange mean value theorem is used to construct the background value as a variable related to k.At the same time,the initial value is set as a variable,and the corresponding optimal parameter and the time response formula are determined according to the minimum value of mean relative error(MRE).Combined with the domestic natural gas annual consumption data,the classical model and the improved GM(1,1)model are applied to the calculation and error comparison respectively.It proves that the improved model is better than any other models. 展开更多
关键词 grey prediction GM(1 1)model background value grey system theory
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Non-equal-interval direct optimizing Verhulst model that x(n) be taken as initial value and its application 被引量:2
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作者 Luo, Youxin Chen, Mianyun +1 位作者 Che, Xiaoyi He, Zheming 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期17-21,共5页
To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) ... To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) of X(0) as the starting condition of the grey differential model. It optimizes a modified β value and the background value, and takes two times fitting optimization. The new model extends equal intervals to non-equal-intervals and is suitable for general data modelling and estimating parameters of the direct Verhulst GM(1,1). The new model does not need to pre-process the primitive data, nor accumulate generating operation (AGO) and inverse accumulated generating operation (IAGO). It is not only suitable for equal interval data modelling, but also for non-equal interval data modelling. As the new information is fully used and two times fitting optimization is taken, the fitting accuracy is the highest in all existing models. The example shows that the new model is simple and practical. The new model is worth expanding on and applying in data processing or on-line monitoring for tests, social sciences and other engineering sciences. 展开更多
关键词 grey system data processing Verhulst GM(1 1) non-equal interval direct modelling OPTIMUM background value two times fitting
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Mathematical Overview of Hypersphere World-Universe Model 被引量:6
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第3期415-437,共23页
The Hypersphere World-Universe Model (WUM) provides a mathematical framework that allows calculating the primary cosmological parameters of the World which are in good agreement with the most recent measurements and o... The Hypersphere World-Universe Model (WUM) provides a mathematical framework that allows calculating the primary cosmological parameters of the World which are in good agreement with the most recent measurements and observations. WUM explains the experimental data accumulated in the field of Cosmology and Astroparticle Physics over the last decades: the age of the World and critical energy density;the gravitational parameter and Hubble’s parameter;temperatures of the cosmic microwave background radiation and the peak of the far-infrared background radiation;the concentration of intergalactic plasma and time delay of Fast Radio Bursts. Additionally, the model predicts masses of dark matter particles, photons, and neutrinos;proposes new types of particle interactions (Super Weak and Extremely Weak);shows inter-connectivity of primary cosmological parameters of the World. WUM proposes to introduce a new fundamental parameter Q in the CODATA internationally recommended values. This paper is the summary of the mathematical results obtained in [1]-[4]. 展开更多
关键词 HYPERSPHERE World-Universe model Primary COSMOLOGICAL Parameters Medium of the World Macroobjects Structure Gravitoelectromagnetism Dark Matter Particles Intergalactic Plasma Microwave background RADIATION FAR-INFRARED background RADIATION Fast Radio BURSTS Emergent Phenomena CODATA
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