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Framework to Model User Request Access Patterns in the World Wide Web
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作者 Richard Hurley Robert Sturgeon 《Journal of Software Engineering and Applications》 2024年第2期69-88,共20页
In this paper, we present a novel approach to model user request patterns in the World Wide Web. Instead of focusing on the user traffic for web pages, we capture the user interaction at the object level of the web pa... In this paper, we present a novel approach to model user request patterns in the World Wide Web. Instead of focusing on the user traffic for web pages, we capture the user interaction at the object level of the web pages. Our framework model consists of three sub-models: one for user file access, one for web pages, and one for storage servers. Web pages are assumed to consist of different types and sizes of objects, which are characterized using several categories: articles, media, and mosaics. The model is implemented with a discrete event simulation and then used to investigate the performance of our system over a variety of parameters in our model. Our performance measure of choice is mean response time and by varying the composition of web pages through our categories, we find that our framework model is able to capture a wide range of conditions that serve as a basis for generating a variety of user request patterns. In addition, we are able to establish a set of parameters that can be used as base cases. One of the goals of this research is for the framework model to be general enough that the parameters can be varied such that it can serve as input for investigating other distributed applications that require the generation of user request access patterns. 展开更多
关键词 Performance modelling world Wide Web SIMULATION User Request Access Patterns FRAMEWORK
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Python Server Page Performance Analysis and Modeling
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作者 Razafindraibe Marolahy Alix Randrianomenjanahary Lala Ferdinand +2 位作者 Rafamantanantsoa Fontaine Mahatody Thomas F. Angelo Raherinirina 《Communications and Network》 2024年第1期1-30,共30页
Today, in the field of computer networks, new services have been developed on the Internet or intranets, including the mail server, database management, sounds, videos and the web server itself Apache. The number of s... Today, in the field of computer networks, new services have been developed on the Internet or intranets, including the mail server, database management, sounds, videos and the web server itself Apache. The number of solutions for this server is therefore growing continuously, these services are becoming more and more complex and expensive, without being able to fulfill the needs of the users. The absence of benchmarks for websites with dynamic content is the major obstacle to research in this area. These users place high demands on the speed of access to information on the Internet. This is why the performance of the web server is critically important. Several factors influence performance, such as server execution speed, network saturation on the internet or intranet, increased response time, and throughputs. By measuring these factors, we propose a performance evaluation strategy for servers that allows us to determine the actual performance of different servers in terms of user satisfaction. Furthermore, we identified performance characteristics such as throughput, resource utilization, and response time of a system through measurement and modeling by simulation. Finally, we present a simple queue model of an Apache web server, which reasonably represents the behavior of a saturated web server using the Simulink model in Matlab (Matrix Laboratory) and also incorporates sporadic incoming traffic. We obtain server performance metrics such as average response time and throughput through simulations. Compared to other models, our model is conceptually straightforward. The model has been validated through measurements and simulations during the tests that we conducted. 展开更多
关键词 Performance Analysis QUEUE Performance model Web Server Internet world Wide Web Web Server Performance
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A Numerical World Ocean General Circulation Model 被引量:12
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作者 张学洪 粱信忠 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1989年第1期44-61,共18页
This paper describes a numerical model of the world ocean based on the fully primitive equations. A 'Standard' ocean state is introduced into the equations of the model and the perturbed thermodynamic variable... This paper describes a numerical model of the world ocean based on the fully primitive equations. A 'Standard' ocean state is introduced into the equations of the model and the perturbed thermodynamic variables are used in the modlc's calculations. Both a free upper surface and a bottom topography are included in the model and a sigma coordinate is used to normalize the model's vertical component. The model has four unevenly-spaced layers and 4 × 5 horizontal resolution based on C-grid system. The finite-difference scheme of the model is designed to conserve the gross available energy in order to avoid fictitious energy generation or decay.The model has been tested in response to the annual mean surface wind stress, sea level air pressure and sea level air temperature as a preliminary step to its further improvement and its coupling with a global atmospheric general circulation model. Some of results, including currents, temperature and sea surface elevation simulated by the mode! arc presented. 展开更多
关键词 A Numerical world Ocean General Circulation model Brook FLEXIBLE THAN 三尸
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A local-world evolving hypernetwork model 被引量:2
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作者 杨光勇 刘建国 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期532-538,共7页
Complex hypernetworks are ubiquitous in the real system. It is very important to investigate the evolution mecha- nisms. In this paper, we present a local-world evolving hypernetwork model by taking into account the h... Complex hypernetworks are ubiquitous in the real system. It is very important to investigate the evolution mecha- nisms. In this paper, we present a local-world evolving hypernetwork model by taking into account the hyperedge growth and local-world hyperedge preferential attachment mechanisms. At each time step, a newly added hyperedge encircles a new coming node and a number of nodes from a randomly selected local world. The number of the selected nodes from the local world obeys the uniform distribution and its mean value is m. The analytical and simulation results show that the hyperdegree approximately obeys the power-law form and the exponent of hyperdegree distribution is 7 = 2 + 1/m. Furthermore, we numerically investigate the node degree, hyperedge degree, clustering coefficient, as well as the average distance, and find that the hypemetwork model shares the scale-flee and small-world properties, which shed some light for deeply understanding the evolution mechanism of the real systems. 展开更多
关键词 local-world evolving hypernetwork model power-law form small-world property
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A Multifractal Detrended Fluctuation Analysis of the Ising Financial Markets Model with Small World Topology 被引量:1
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作者 张昂辉 李晓温 +1 位作者 苏桂锋 张一 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期13-16,共4页
We present a multifractal detrended fluctuation analysis (MFDFA) of the time series of return generated by our recently-proposed Ising financial market model with underlying small world topology. The result of the M... We present a multifractal detrended fluctuation analysis (MFDFA) of the time series of return generated by our recently-proposed Ising financial market model with underlying small world topology. The result of the MFDFA shows that there exists obvious multifractal scaling behavior in produced time series. We compare the MFDFA results for original time series with those for shuffled series, and find that its multifractal nature is due to two factors: broadness of probability density function of the series and different correlations in small- and large-scale fluctuations. This may provide new insight to the problem of the origin of multifractality in financial time series. 展开更多
关键词 A Multifractal Detrended Fluctuation Analysis of the Ising Financial Markets model with Small world Topology
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5D World-Universe Model. Multicomponent Dark Matter 被引量:3
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2015年第2期55-71,共17页
5D World-Universe Model (WUM) is based on the decisive role of the Medium of the World com-posed of massive particles: protons, electrons, photons, neutrinos, and Dark Matter Particles (DMP). The model forecasts the m... 5D World-Universe Model (WUM) is based on the decisive role of the Medium of the World com-posed of massive particles: protons, electrons, photons, neutrinos, and Dark Matter Particles (DMP). The model forecasts the masses of DMP, discusses the possibility of all macroobject cores consisting of DMP (galaxy clusters, galaxies, star clusters, extrasolar systems, and planets), and explains the diffuse cosmic gamma-ray background radiation as the sum of contributions of multicomponent dark matter annihilation. The signatures of DMP annihilation with expected masses of 1.3 TeV, 9.6 GeV, 70 MeV, 340 keV, and 3.7 keV, are found in spectra of the diffuse gamma-ray background and the emission of various macroobjects in the World. The correlation between different emission lines in spectra of macroobjects is connected to their structure, which depends on the composition of the cores and surrounding shells made up of DMP. Consequently, the diversity of Very High Energy (VHE) gamma-ray sources in the World has a clear explanation. 展开更多
关键词 5D world-Universe model Medium of the world Dark Matter Particles CORES of Macroobjects GAMMA-RAY Background Radiation PIONEER ANOMALY
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The Alternative Mathematical Models of the World 被引量:1
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作者 Salahaddin Khalilov 《Journal of Philosophy Study》 2014年第5期321-333,共13页
关键词 数学模型 世界 混合物 替代性 单位 倍数 分数
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BRAIN INJURY BIOMECHANICS IN REAL WORLD VEHICLE ACCIDENT USING MATHEMATICAL MODELS 被引量:10
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作者 YANG Jikuang XU Wei OTTE Dietmar 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第4期81-86,共6页
This paper aims at investigating brain injury mechanisms and predicting head injuries in real world accidents. For this purpose, a 3D human head finite element model (HBM-head) was developed based on head-brain anat... This paper aims at investigating brain injury mechanisms and predicting head injuries in real world accidents. For this purpose, a 3D human head finite element model (HBM-head) was developed based on head-brain anatomy. The HBM head model was validated with two experimental tests. Then the head finite element(FE) model and a multi-body system (MBS) model were used to carry out reconstructions of real world vehicle-pedestrian accidents and brain injuries. The MBS models were used for calculating the head impact conditions in vehicle impacts. The HBM-head model was used for calculating the injury related physical parameters, such as intracranial pressure, stress, and strain. The calculated intracranial pressure and strain distribution were correlated with the injury outcomes observed from accidents. It is shown that this model can predict the intracranial biomechanical response and calculate the injury related physical parameters. The head FE model has good biofidelity and will be a valuable tool for the study of injury mechanisms and the tolerance level of the brain. 展开更多
关键词 Skull-brain FE model Head injury Real-world vehicle accident
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Hypersphere World-Universe Model. Tribute to Classical Physics 被引量:3
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第3期441-470,共30页
This manuscript summarizes the results of Classical Physics before Quantum Mechanics and Hypotheses proposed by classical physicists from the 17th until the beginning of 21st century. We then proceed to unify these re... This manuscript summarizes the results of Classical Physics before Quantum Mechanics and Hypotheses proposed by classical physicists from the 17th until the beginning of 21st century. We then proceed to unify these results into a single coherent picture in frames of the developed Hypersphere World-Universe Model (WUM). The Model proposes 5 types of Dark Matter particles and predicts their masses;models the origin, evolution, and structure of the World and Macroobjects;provides a mathematical framework that ties together a number of Fundamental constants and allows for direct calculation of their values. 展开更多
关键词 Classical Physics HYPERSPHERE world-Universe model Medium of the world Dark Matter Particles Gravitoelectromagnetism COSMIC NEUTRINO Background Macroobjects Structure Emergent Phenomena Q-Dependent COSMOLOGICAL Parameters
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Optimizing Movement of Students from Hostels to Lecture Rooms in a Potential World Class University Using Transportation Model
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作者 Michael C. Agarana Aniekeme I. Udoh Amenawon I. Ehigbochie 《Applied Mathematics》 2018年第6期633-646,共14页
Transportation issue is one of the significant zones of utilization of Linear Programming Model. In this paper, transportation model is utilized to decide an ideal answer for the transportation issue in a run of the m... Transportation issue is one of the significant zones of utilization of Linear Programming Model. In this paper, transportation model is utilized to decide an ideal answer for the transportation issue in a run of the mill world class university utilizing Covenant University as a contextual analysis. Covenant University is a potential world class University. The quick development of Covenant University Campus over the most recent fourteen years affects its transportation framework. This paper particularly takes a gander at streamlining the time spent by the students moving from their lodgings to lecture rooms. Google guide was utilized to figure the separation and time between every cause and every goal. North-west corner technique, Least Cost strategy and Vogel’s estimation technique were utilized to decide the underlying fundamental plausible arrangement (initial feasible solution) and MODI strategy was utilized to locate the ideal arrangement (optimal solution). The last outcome demonstrates that the development of understudies from hostel to lecture rooms can be streamlined if the total time spent is decreased. 展开更多
关键词 TRANSPORTATION model world CLASS UNIVERSITY Optimization
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5D World-Universe Model. Neutrinos. The World 被引量:9
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第1期1-18,共18页
In this manuscript we discuss mass-varying neutrinos and propose their energy density to exceed that of baryonic and dark matter. We introduce cosmic Large Grains whose mass is about Planck mass, and their temperature... In this manuscript we discuss mass-varying neutrinos and propose their energy density to exceed that of baryonic and dark matter. We introduce cosmic Large Grains whose mass is about Planck mass, and their temperature is around 29 K. Large Grains are in fact Bose-Einstein condensates of proposed dineutrinos, and are responsible for the cosmic Far-Infrared Background (FIRB) radiation. The distribution of the energy density of all components of the World (protons, electrons, photons, neutrinos, and dark matter particles) is considered. We present an overview of the World- Universe Model (WUM) and pay particular attention to the self-consistent set of time-varying values of basic parameters of the World: the age and critical energy density;Newtonian parameter of gravitation and Hubble’s parameter;temperatures of the cosmic Microwave Background radiation and the peak of the cosmic FIRB radiation;Fermi coupling parameter and coupling parameters of the proposed Super-Weak and Extremely-Weak interactions. Additionally, WUM forecasts the masses of dark matter particles, axions, and neutrinos;proposes two fundamental parameters of the World: fine-structure constant α and the quantity Q which is the dimensionless value of the fifth coordinate, and three fundamental physical units: basic unit of momentum, energy density, and energy flux density. WUM suggests that all time-dependent parameters of the World are inter- connected and in fact dependent on Q. We recommend adding the quantity Q to the list of the CODATA-recommended values. 展开更多
关键词 5D world-Universe model Medium of the world Mass-Varying Neutrinos Dineutrinos Bose- Einstein Condensates Far-Infrared Background Radiation Time-Varying Parameters of the world
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The applications of Bayesian models in real-world studies of traditional Chinese medicine:a primer 被引量:1
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作者 Jing-Bo Zhai Jiang Li Jing Chen 《Traditional Medicine Research》 2017年第2期88-93,共6页
真实世界研究适用于中医药领域.目前,尚无公认的用于真实世界研究的统计分析方法.随着计算机技术的发展,贝叶斯统计越来越受到生物医学领域的重视.本文在介绍贝叶斯统计和真实世界研究的基础上,讨论了在中医药领域的真实世界研究中使用... 真实世界研究适用于中医药领域.目前,尚无公认的用于真实世界研究的统计分析方法.随着计算机技术的发展,贝叶斯统计越来越受到生物医学领域的重视.本文在介绍贝叶斯统计和真实世界研究的基础上,讨论了在中医药领域的真实世界研究中使用贝叶斯模型的注意事项和面临的挑战. 展开更多
关键词 中医药 真实世界研究 贝叶斯模型
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Phase Transitions of an Epidemic Spreading Model in Small-World Networks
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作者 华达银 高科 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第6期1127-1131,共5页
我们建议一个修改 susceptible-infected-refractory-susceptible (先生) 模型调查在 WattsStrogatz (WS ) 散布小世界的网络的流行病的全球摆动。当单个免疫不在一个有免疫力的时期慢慢地变化或腐烂时,系统能从感染展出复杂转变,这... 我们建议一个修改 susceptible-infected-refractory-susceptible (先生) 模型调查在 WattsStrogatz (WS ) 散布小世界的网络的流行病的全球摆动。当单个免疫不在一个有免疫力的时期慢慢地变化或腐烂时,系统能从感染展出复杂转变,这被发现到一个大振幅的静止状态没有感染支撑了摆动或一个吸收状态。当免疫在有免疫力的时期很快腐烂时,到全球摆动的转变消失,没有摆动。基于时间空间的进化模式和阶段图,而且,一个长免疫时期在小世界的网络在全球摆动的出现起一个重要作用,这被揭示。 展开更多
关键词 小世界网络 网络模型 流行病 持续振荡 相变 静止状态 机体免疫力 免疫期
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5D World-Universe Model Space-Time-Energy 被引量:1
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2015年第1期25-34,共10页
5D Space-Time-Energy World-Universe Model is a unified model of the World built around the concept of Medium, composed of massive particles (protons, electrons, photons, neutrinos, and dark matter particles). The Mode... 5D Space-Time-Energy World-Universe Model is a unified model of the World built around the concept of Medium, composed of massive particles (protons, electrons, photons, neutrinos, and dark matter particles). The Model provides a mathematical framework that enables precise calculation of medium-bound physical parameters: Hubble’s parameter, intergalactic plasma parameters, temperature of microwave background radiation and the rest mass of photons. This paper aligns the World-Universe Model (WUM) with the theoretical framework developed by Prof. P. S. Wesson, albeit assigning a new physical meaning to the fifth coordinate. In the World-Universe Model, the fifth dimension is associated with the total energy of the Medium of the World, and the gravitomagnetic parameter of the Medium serves as the dimension-transposing parameter. 展开更多
关键词 5D world-Universe model Space-Time-Energy Medium of the world Intergalactic Plasma Microwave BACKGROUND Radiation Mass VARYING PHOTONS
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Small World Effects in a Harmonious Unifying Hybrid Preferential Model Networks
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作者 FANG Jin-Qing BI Qiao LI Yong LU Xin-Biao LIU Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2X期377-383,共7页
关键词 杂种择优模型 小世界效应 网络科学 网络技术
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Application of random walk model to fit temperature in 46 gamma world cities from 1901 to 1998 被引量:3
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作者 Shaomin Yan Guang Wu 《Natural Science》 2010年第12期1425-1431,共7页
Very recently, we have applied the random walk model to fit the global temperature anomaly, CRUTEM3. With encouraging results, we apply the random walk model to fit the temperature walk that is the conversion of recor... Very recently, we have applied the random walk model to fit the global temperature anomaly, CRUTEM3. With encouraging results, we apply the random walk model to fit the temperature walk that is the conversion of recorded tem-perature and real recorded temperature in 46 gamma world cities from 1901 to 1998 in this study. The results show that the random walk model can fit both temperature walk and real recorded temperature although the fitted results from other climate models are unavailable for comparison in these 46 cities. Therefore, the random walk model can fit not only the global temperature anomaly, but also the real recorded temperatures in various cities around the world. 展开更多
关键词 GAMMA world CITIES Global WARMING modeling Random WALK TEMPERATURE Change
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‘China model'enriches world experience in growth
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作者 王伟光 《China Economist》 2009年第1期11-21,共11页
|Editorial Note| Since reform and opening up,China has embarked on a path of development featuring socialism with Chinese characteristics,scoring remarkable achievements that have drawn attention from all over the wor... |Editorial Note| Since reform and opening up,China has embarked on a path of development featuring socialism with Chinese characteristics,scoring remarkable achievements that have drawn attention from all over the world.What has reform and opening up achieved?What are its experiences?What are the intrinsic values of socialism with Chinese characteristics?How is China’s development path viewed in the international community? This paper gives an overview of these questions,shedding light on the problems that the country faces and optimism about its future. 展开更多
关键词 China model’enriches world experience in growth CPC
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Mathematical Overview of Hypersphere World-Universe Model 被引量:3
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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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Overview of Hypersphere World-Universe Model 被引量:14
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第4期593-632,共40页
This paper provides an overview of the Hypersphere World-Universe Model (WUM). WUM unifies and simplifies existing cosmological models and results into a single coherent picture, and proceeds to discuss the origin, ev... This paper provides an overview of the Hypersphere World-Universe Model (WUM). WUM unifies and simplifies existing cosmological models and results into a single coherent picture, and proceeds to discuss the origin, evolution, structure, ultimate fate, and primary parameters of the World. 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;gamma-ray background and cosmic neutrino background;macrostructure of the world and macroobjects structure. Additionally, the model makes predictions pertaining to masses of dark matter particles, photons, and neutrinos, proposes new types of particle interactions (Super Weak and Extremely Weak), and shows inter-connectivity of primary cosmological parameters of the world and the rise of the solar luminosity during the last 4.6 Byr. The model proposes to introduce a new fundamental parameter Q in the CODATA internationally recommended values. 展开更多
关键词 Hypersphere world-Universe model Medium of the world Macroobjects Structure Gravitoelectromagnetism Dark Matter Particles Intergalactic Plasma Microwave Background Radiation Far-Infrared Background Radiation Gamma-Ray Background Radiation Cosmic Neutrino Background Q-Dependent Cosmological Parameters Emergent Phenomena Grand Unified Theory CODATA
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Ideas on an Alternative Cosmological World Model with Different Initial Conditions
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作者 Guido Zbiral 《Journal of Modern Physics》 2015年第3期346-361,共16页
The actual world model, the “Standard Model of Cosmology” (SMC), which dates back to the 1950s, no longer corresponds to the latest state of knowledge on the cosmos. By way of example, the assumption made in the SMC... The actual world model, the “Standard Model of Cosmology” (SMC), which dates back to the 1950s, no longer corresponds to the latest state of knowledge on the cosmos. By way of example, the assumption made in the SMC that the expansion of the cosmos is continually being reduced due to the effect of the gravitation exerted on all the matter in the universe is now contradicted by recent measurements. The reason for the expansion of cosmic space in accordance with Hubble’s Law is not physically explained by the SMC but merely stated as a fact. Another example is provided by the “dark phenomena”, which make up by far the greatest part of the energy of the cosmos, and exert a dominant influence on its behaviour. In spite of intensive research over the decades to provide answers to these as well as other open issues in cosmology, no satisfactory and plausible answers have hitherto been found. It is indeed time to propose an alternative cosmological world model to the SMC in the light of the latest insights on the universe. 展开更多
关键词 Transition States of PHOTONS GRAVITATION DARK Matter DARK Energy Standard model of Cosmology ALTERNATIVE COSMOLOGICAL world model
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