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RAPD Markers and Genetic Information Entropy in Environmental Monitoring: A Case Study with Wild Mushrooms
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作者 Charoula Psallida Dimitrios Argyropoulos 《Journal of Geoscience and Environment Protection》 2023年第9期28-39,共12页
Mushrooms have a remarkable scientific value due to their nutritional, medicinal properties and industrial applications in enzyme production, so that effort in the maintenance of native wild mushroom varieties is incr... Mushrooms have a remarkable scientific value due to their nutritional, medicinal properties and industrial applications in enzyme production, so that effort in the maintenance of native wild mushroom varieties is increasing. The present study focuses on the use of Random Amplified Polymorphic DNA (RAPD) markers for biodiversity measure of wild mushroom species of the Northwest mountainous region of Greece. Data mining of similarity matrices from RAPD analysis was used to extract measurable entropy parameters for mushroom biodiversity monitoring based on Shannon’s information entropy. Shannon information index provides an easy assessment of the entropy of the genetic information of the germplasm per mushroom species while the total equitability index (E<sub>H</sub>) = 0.871 offers an overall estimation of the genetic variation evenness of all species in the population of the studied mushrooms. Application of RAPDs with parallel entropy analysis is an easily applicable and low-cost valuable technology in environmental monitoring, using genetic information of wild mushroom species as an indicator that can lead to future actions in biodiversity maintenance and germplasm protection. The provided methodology can serve as a pilot procedure enriched with other environmental factors to monitor and protect wild mushroom communities native to the Greek countryside or in any part of the world and provide comparable results about biodiversity from different regions using common entropy indices. 展开更多
关键词 Random Amplified Polymorphic DNA shannon’s Index entropy BIODIVERsITY DENDROGRAM
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Entanglement Quantifier Based on Atomic Wehrl Entropy for Non-Linear Interaction between a Single Two-Level Atom and SU(1,1) Quantum System 被引量:1
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作者 Sayed Abdel-Khalek Manal Al-Quthami Mohamed M. A. Ahmed 《Journal of Quantum Information Science》 2014年第1期44-53,共10页
In this paper, we study the dynamics of the atomic inversion, scaled atomic Wehrl entropy and marginal atomic Wehrl density for a single two-level atom interacting with SU(1,1) quantum system. We obtain the expectatio... In this paper, we study the dynamics of the atomic inversion, scaled atomic Wehrl entropy and marginal atomic Wehrl density for a single two-level atom interacting with SU(1,1) quantum system. We obtain the expectation values of the atomic variables using specific initial conditions. We examine the effects of different parameters on the scaled atomic Wehrl entropy and marginal atomic Wehrl density. We observe an interesting monotonic relation between the different physical quantities for different values of the initial atomic position and detuning parameter. 展开更多
关键词 scaled ATOMIC wehrl entropy ATOMIC Q-FUNCTION ATOMIC Inversion
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基于D-S证据理论改进AHP-熵权的流域洪涝灾害评估研究
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作者 苑希民 高瑞梅 +1 位作者 田福昌 侯玮 《水资源与水工程学报》 CSCD 北大核心 2024年第1期9-16,共8页
考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小... 考虑致灾因子危险性、孕灾环境敏感性以及承灾体易损性,选取指标构建小清河流域洪涝灾害风险评估指标体系,提出一种基于D-S证据理论的改进AHP-熵权法计算指标权重,求取洪涝灾害风险指数,运用自然断点分级法确定洪涝灾害风险等级,分析小清河流域洪涝灾害风险空间分布情况。结果表明:小清河流域洪涝灾害风险总体上表现出南低北高的趋势,其中高风险区和较高风险区分别占流域面积的8.7%和14.3%,主要分布在小清河干流以及主要支流两岸。所得评估结果同“利奇马”台风发生期间实际洪灾风险分布情况一致,对比证明基于D-S证据理论的改进AHP-熵权法优于AHP和熵权法,可为小清河流域防洪减灾决策提供依据。 展开更多
关键词 D-s证据理论 AHP 熵权法 洪涝灾害评估 小清河流域
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水泵水轮机S特性区能量损失及流动特性研究
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作者 王李科 姚亮 +3 位作者 冯建军 朱国俊 卢金玲 阮辉 《水利学报》 EI CSCD 北大核心 2024年第3期344-354,366,共12页
为了调节电网的稳定性,抽水蓄能电站需要频繁启停和变换工况运行,导致水泵水轮机容易进入S特性区,机组振动增加,并网失败。本文以模型水泵水轮机为研究对象,采用熵产理论详细分析了S特性区不同工况下的能量损失规律,明确了熵产率分布与... 为了调节电网的稳定性,抽水蓄能电站需要频繁启停和变换工况运行,导致水泵水轮机容易进入S特性区,机组振动增加,并网失败。本文以模型水泵水轮机为研究对象,采用熵产理论详细分析了S特性区不同工况下的能量损失规律,明确了熵产率分布与内部流动结构的关系。结果表明:S特性区内近飞逸工况总熵产最大,约为设计工况的5.1倍,脉动熵产占据的比例接近80%,随着流量的减小,转轮熵产占比逐渐降低,活动导叶和尾水管的熵产占比增加。小流量工况转轮进口靠近下环位置首先出现了明显的漩涡,导致了活动导叶出口和转轮进口的高熵产区,随着流量进一步减小,漩涡逐渐向上冠转移,并且切向速度增大,在转轮进口形成挡水环,阻碍水流进入转轮,在无叶区内出现了环状分布的高熵产区。反水泵工况,水流在低压边与逆时针旋转的叶片撞击,导致水流很难进入叶片内部,形成了大尺度的回流涡结构;双列叶栅内充满大量涡结构,导致活动导叶吸力面的熵产率增大,并且向固定导叶传播。 展开更多
关键词 水泵水轮机 s特性 熵产理论 回流涡
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Performance Evaluation of Public Bus Transportation by Using DEA Models and Shannon’s Entropy:An Example From a Company in a Large City of China 被引量:7
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作者 Zicheng Liu Naiqi Wu +1 位作者 Yan Qiao Zhiwu Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第4期779-795,共17页
The purpose of this paper is to assess the operational efficiency of a public bus transportation via a case study from a company in a large city of China by using data envelopment analysis(DEA)model and Shannon’s ent... The purpose of this paper is to assess the operational efficiency of a public bus transportation via a case study from a company in a large city of China by using data envelopment analysis(DEA)model and Shannon’s entropy.This company operates 37 main routes on the backbone roads.Thus,it plays a significant role in public transportation in the city.According to bus industry norms,an efficiency evaluation index system is constructed from the perspective of both company operations and passenger demands.For passenger satisfaction,passenger waiting time and passenger-crowding degree are considered,and they are undesirable indicators.To describe such indicators,a superefficient DEA model is constructed.With this model,by using actual data,efficiency is evaluated for each bus route.Results show that the DEA model with Shannon’s entropy being combined achieves more reasonable results.Also,sensitivity analysis is presented.Therefore,the results are meaningful for the company to improve its operations and management. 展开更多
关键词 Performance evaluation public transportation system shannon’s entropy super-efficiency data envelopment analysis undesirable outputs
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The Topological Entropy Mechanism of Coronavirus Disease 2019 (COVID-19) 被引量:1
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作者 Ruomeng Xu Ludan Lei +2 位作者 Ruihua Qin Zhende Huang Kuo-Chen Chou 《Natural Science》 2020年第12期737-742,共6页
The biological </span><span style="font-family:Verdana;font-size:12px;">principal</span><span style="font-family:Verdana;font-size:12px;"> or its detailed mechanism for the ... The biological </span><span style="font-family:Verdana;font-size:12px;">principal</span><span style="font-family:Verdana;font-size:12px;"> or its detailed mechanism for the pandemic coronavirus disease 2019 (COVID-19) has been investigated and analyzed from the topological entropy approach. The findings thus obtained have provided very useful clues and information for developing both powerful and safe vaccines against the pandemic COVID-19. 展开更多
关键词 VACCINE Cellular CORONAVIRUs Pandemic COVID-19 spatial and Time entropy Topological entropy Chou’s 5-steps Rule
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基于FPGA的AES和ECC算法图像加密
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作者 方应李 方玉明 《电子科技》 2024年第6期92-97,共6页
随着数字图像的使用次数日益增多,保护机密图像数据免受未经授权的访问较为重要。针对数字图像在通信、存储和传输等领域存在的安全问题,文中基于对称算法模型和非对称算法模型的优点提出一种具有高安全性和高速度性的数字信封技术密码... 随着数字图像的使用次数日益增多,保护机密图像数据免受未经授权的访问较为重要。针对数字图像在通信、存储和传输等领域存在的安全问题,文中基于对称算法模型和非对称算法模型的优点提出一种具有高安全性和高速度性的数字信封技术密码方案。该方案以AES(Advanced Encryption Standard)和ECC(Elliptic Curve Cryptography)为基础,经优化后用于对称密钥共享的ECC硬件架构来提高密钥的安全性。通过加入伪随机数、使用列移位替代列混淆运算以及三维S-box等方式对传统AES进行优化,在保持香农扩散和混淆原理的同时降低了时间复杂性。基于FPGA(Field Programmable Gate Array)实现AES算法的数字图像加密仿真以及性能测试。测试结果表明,所提密码方案具有快速性、高安全性和有效性等优点,能够有效地实现图像加密。 展开更多
关键词 数字图像 数字信封 AEs算法 ECC算法 三维s-box FPGA 信息熵 相关系数
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Shear viscosity to entropy density ratio in BUU transport model 被引量:1
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作者 LI Shaoxin FANG Deqing +1 位作者 MA Yugang ZHOU Chenglong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2011年第4期235-239,共5页
Shear viscosity (η) is a basic transport coefficient of the medium.In this work,we calculate shear viscosity to entropy density ratio (η/S) of an equilibrated system in intermediate energy heavy ion collisions withi... Shear viscosity (η) is a basic transport coefficient of the medium.In this work,we calculate shear viscosity to entropy density ratio (η/S) of an equilibrated system in intermediate energy heavy ion collisions within the framework of the Boltzmann-Uehling-Uhlenbeck model (BUU) model.After the equilibration of Au + Au system at central collision in a fixed volume is reached,temperature,pressure and energy density are extracted by the phase space information and then η/S is calculated using the Green-Kubo formulas.The results show that η/S drops with the incident energy and its value is not so drastically different from the RHIC results. 展开更多
关键词 剪切粘度 运输模型 密度比 BOLTZMANN 中能重离子碰撞 平衡系统 运输系数
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基于最大信息系数法和邓熵的D-S证据理论改进
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作者 王刚 徐维磊 田裕鹏 《计算机应用文摘》 2024年第4期114-118,123,共6页
物联网中大量传感器采集的数据存在不确定性,针对D-S证据理论在处理冲突证据时融合决策结果与事实相悖的问题,文章提出一种新的基于改进D-S证据理论的多传感器数据融合算法,首先使用最大信息系数法计算证据间的可信度;然后结合信息熵对... 物联网中大量传感器采集的数据存在不确定性,针对D-S证据理论在处理冲突证据时融合决策结果与事实相悖的问题,文章提出一种新的基于改进D-S证据理论的多传感器数据融合算法,首先使用最大信息系数法计算证据间的可信度;然后结合信息熵对证据的不确定度进行分析,以确定新的权重;最后使用Dempster组合规则得到融合结果。算例分析表明,文章所提方法能有效融合冲突证据,较经典算法有较高的基本概率分配。将所提方法用于传感器数据处理,不仅能降低数据中存在的不确定性,还能有效处理D-S理论中的冲突问题,从而得到较为准确的融合结果。 展开更多
关键词 D-s证据理论 最大信息系数 邓熵 数据融合
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Entropy Analysis of Vapor-Compression Refrigeration System by Using the Second Law of Thermodynamics
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作者 杨洪海 《Journal of China Textile University(English Edition)》 EI CAS 1999年第4期42-44,共3页
By means of the Second Law of Thermodynamics,thispaper gives out the entropy analysis method for vapor-comperession refrigeration system.The thermal irrevers-ibility of the system charged with R12 and its hopeful al-t... By means of the Second Law of Thermodynamics,thispaper gives out the entropy analysis method for vapor-comperession refrigeration system.The thermal irrevers-ibility of the system charged with R12 and its hopeful al-ternative refrlgerant R134a have been studied respective-ly.On the basis of all the research results of this paper,the measure used to save energy for vapor-compressionrefrigeration system has been put out. 展开更多
关键词 Vapor - Compression REFRIGERATION system sec-ond Law of THERMODYNAMICs entropy ANALYsIs Alternative REFRIGERANT of CFC’s
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基于改进D-S证据理论的相控阵雷达作战效能评估
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作者 郑丽莎 尹东亮 王旋 《系统工程与电子技术》 EI CSCD 北大核心 2024年第4期1330-1336,共7页
针对相控阵雷达作战效能评估中战场环境等不确定因素的影响,采用改进Dempster-Shafer(D-S)证据理论对其进行作战效能评估方法的优化。首先,通过构建相控阵雷达作战效能评估指标体系,明确评估指标并赋值权。其次,引入Kulsinski差异和模... 针对相控阵雷达作战效能评估中战场环境等不确定因素的影响,采用改进Dempster-Shafer(D-S)证据理论对其进行作战效能评估方法的优化。首先,通过构建相控阵雷达作战效能评估指标体系,明确评估指标并赋值权。其次,引入Kulsinski差异和模糊熵方法,对传统的D-S证据理论进行改进,减少指标在融合过程中的融合权重不确定性的影响。最后,通过改进D-S证据理论对评估指标进行数据融合,建立评估准确性较高的相控阵雷达作战效能评估模型。通过算例验证分析,所提方法能够有效减少融合过程中的不确定性影响,可实现相控阵雷达作战效能评估的目的,提高作战效能评估精度。 展开更多
关键词 相控阵雷达 Dempster-shafer(D-s)证据理论 作战效能评估 Kulsinski差异 模糊熵
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Robot’s Emotion Decision by Energy and Entropy Concepts
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作者 Won-hyong LEE Myung-jin CHUNG 《Journal of Measurement Science and Instrumentation》 CAS 2010年第4期368-371,共4页
This study is to introduce concepts of energy and entropy to describe a robot's emoton decisien. It chooses the dimensional approach based on factors of pleasure and arousal for the merit of the interpolation between... This study is to introduce concepts of energy and entropy to describe a robot's emoton decisien. It chooses the dimensional approach based on factors of pleasure and arousal for the merit of the interpolation between enotions. Especially, Circumplex model which has also two axes: pleasure and arousal is used. Besides, the model indicates how emotions are distributed in the two-dimensional plane. Then by the definition of psychodynamicsthe energy states (mental energy and physical energy) are matched to pleasure and arousal respectively that are the basis of Circumplex model. The mental energy is updated by the result of Prospect theory which measures the value of gain and loss as pleasure factor. And the physical energy is updated by the result of hedonic scaling which measures levels of arousal from pleasure computed by Prospect theory, and the result of intensity of stimuli. Then the energy states are fed by entropy. The feedback loop by entropy satisfies the 2nd law of thermodynamics. The energy states generated by stimuli and fed by entropy take a position in the plane of Circumplex model. Then distances between the current position and other emotions are cornputed to get a level of each emotion, proportional to the inverse of the distance. 展开更多
关键词 robot's emotion emotion generation emotion decision energy and entropy
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An Algorithm to Generate Probabilities with Specified Entropy
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作者 Om Parkash Priyanka Kakkar 《Applied Mathematics》 2015年第12期1968-1976,共9页
The present communication offers a method to determine an unknown discrete probability distribution with specified Tsallis entropy close to uniform distribution. The relative error of the distribution obtained has bee... The present communication offers a method to determine an unknown discrete probability distribution with specified Tsallis entropy close to uniform distribution. The relative error of the distribution obtained has been compared with the distribution obtained with the help of mathematica software. The applications of the proposed algorithm with respect to Tsallis source coding, Huffman coding and cross entropy optimization principles have been provided. 展开更多
关键词 entropy source Coding Kraft’s INEQUALITY HUFFMAN CODE Mean CODEWORD Length Uniquely Decipherable CODE
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An Entropy Approach to Tesla’s Discovery of Wireless Power Transmission
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作者 Salama Abdelhady 《Journal of Electromagnetic Analysis and Applications》 2013年第4期157-161,共5页
Following an entropy approach, the electric current can be postulated as a flow of electromagnetic waves that has an electric potential. Such postulate is verified in this article by results of experimental measuremen... Following an entropy approach, the electric current can be postulated as a flow of electromagnetic waves that has an electric potential. Such postulate is verified in this article by results of experimental measurement then it is applied to review Tesla’s discovery of wireless power transmission. Tesla discovered the wireless transmission of electric power during his operation in an entirely new domain of physics based on abrupt discharging of electrostatic charges. He realized that electrons were not responsible for such discovered phenomena. So, he called the new energy as “Radiant Electricity”. He didn’t identify that the true nature of electric current was a flow of electromagnetic waves that can be normally radiated through air. So, he proposed the term “Aether gas” to describe the discovered transfer of the electric charges by radiation from his designed tower, though air, to specified receivers. Following an entropy approach, the nature of the discovered radiated energy can be identified as electromagnetic waves that have an electric potential. So, the followed approach succeeds in eliminating the confusing observations of Tesla’s measurements in his famous experiment and the confusions found in modern literature that deals with such energy as an “Ambiguous Radiant Energy”. 展开更多
关键词 entropy Tesla’s DIsCOVERY Radiant ENERGY ELECTROMAGNETIC WAVEs
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Modeling and Mapping of Urban Sprawl Pattern in Cairo Using Multi-Temporal Landsat Images, and Shannon’s Entropy
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作者 Hala A. Effat Mohamed A. El Shobaky 《Advances in Remote Sensing》 2015年第4期303-318,共16页
Cairo city, being the Egypt’s industrial and cultural center, has a problem of rapid urban sprawl. The city has an extremely high population density which is continuously increasing through informal settlements that ... Cairo city, being the Egypt’s industrial and cultural center, has a problem of rapid urban sprawl. The city has an extremely high population density which is continuously increasing through informal settlements that grow by sprawling due to migration from the Nile Delta villages and the high population growth rates. The present study attempts to understand, detect and quantify the spatial pattern of Cairo’s urban sprawl using Shannon’s entropy and multi-temporal Landsat TM and ETM images acquired for the period from 1984 to 2013. Supervised classification was applied to extract the built-up areas and to measure the changes in the urban land-use class among the city wards. Shannon’s entropy was applied to model the city’s urban sprawl, trend and spatial change. The entropy values for the city’s electoral wards were modeled and used in an interpolation function to create an entropy surface (index) for each acquired temporal image. Such index indicates the spatial pattern of the urban sprawl and provides a visual comparison of the entropy phenomenon in such wards. Results indicate that Shannon’s entropy index increased from (1.4615) in year 1984 to (2.1023) in year 2013, indicating more dispersed urban growth, a sign of urban sprawl. The maximum entropy values are found in the eastern wards namely El Nozha, Awal Nasr District, Thany Nasr-District, El Salam, El Marg and El Bassatein. A regression analysis was carried for the population growth rate and the built-up areas. Findings help in understanding the sprawl patterns and dynamics among Cairo’s electoral wards and provide a visual comparison. The applied methodology provides explanations and facilitates tracing and measuring the urban sprawl which is needed by decision makers and city planners of mega cities. 展开更多
关键词 shannon’s entropy Urban Growth sPRAWL Patterns LANDsAT CAIRO EGYPT
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An Extended Interpretation of the Concept of Entropy Opening a Link between Thermodynamics and Relativity
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作者 Jean-Louis Tane 《Natural Science》 2014年第7期503-513,共11页
It is well known that thermodynamics raises conceptual difficulties. Far to be limited to students having to learn the subject, this impression is sometimes mentioned by specialists themselves who confess not being to... It is well known that thermodynamics raises conceptual difficulties. Far to be limited to students having to learn the subject, this impression is sometimes mentioned by specialists themselves who confess not being totally sure of the consistency of the thermodynamic theory, despite the fact that its practical usefulness is indisputable. The present paper deals with this interesting question and leads to the idea that there is an imperfect convergence between the way of using the thermodynamic tool and the way of understanding its significance. Illustrated by a very simple example, the discussion can be followed by every scientist having the fundamental basis in thermodynamics. The suggested hypothesis is that the Einstein mass-energy relation is closely associated to the concept of entropy, opening a link between thermodynamics and relativity. 展开更多
关键词 THERMODYNAMICs REVERsIBILITY IRREVERsIBILITY ENERGY entropy Einstein’s Mass-Energy Relation RELATIVITY Gravitation
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A NUMERICAL METHOD OF K-S ENTROPY CALCULATION FOR A STRANGE ATTRACTOR
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作者 赵南 刘曾荣 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1992年第1期16-20,共5页
Based directly on the original definition of K-S entropy, a new algorithm for calculating K-S entropy from chaotic time series is developed by using some techniques of coding and code operation.
关键词 CHAOs K-s entropy numerical method CODING
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An Entropy Approach to the Natures of the Electric Charge and Magnetic Flux
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作者 Salama Abdelhady Mohamed S. Abdelhady 《Journal of Electromagnetic Analysis and Applications》 2015年第11期265-275,共11页
As a result of investigating analytically and experimentally the interchangeability between thermal, electrical and magnetic energies, it is proved in the presented study that the electric and magnetic energies have a... As a result of investigating analytically and experimentally the interchangeability between thermal, electrical and magnetic energies, it is proved in the presented study that the electric and magnetic energies have an equivalent grade and nature as the thermal energy. So, the natural flow of electric charges and magnetic flux is associated also by increase of entropy of universe, similar to the heat, and has the same nature of waves as the electromagnetic heat radiation. Casting the Maxwell’s wave equation into an energy frame of reference that replaces the time in wave equations by entropy, it is possible to represent the electric charges and magnetic flux as electromagnetic waves of electric and magnetic potentials. Such results lead to modify exclusively the definition of the physical nature of the electric charge and magnetic flux which is unavailable in literature. 展开更多
关键词 Heat Electric Current Magnetic FLUX entropy ELECTROMAGNETIC WAVEs Maxwell’s WAVE EQUATION
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Multi-Threshold Algorithm Based on Havrda and Charvat Entropy for Edge Detection in Satellite Grayscale Images
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作者 Mohamed A. El-Sayed Hamida A. M. Sennari 《Journal of Software Engineering and Applications》 2014年第1期42-52,共11页
Automatic edge detection of an image is considered a type of crucial information that can be extracted by applying detectors with different techniques. It is a main tool in pattern recognition, image segmentation, and... Automatic edge detection of an image is considered a type of crucial information that can be extracted by applying detectors with different techniques. It is a main tool in pattern recognition, image segmentation, and scene analysis. This paper introduces an edge-detection algorithm, which generates multi-threshold values. It is based on non-Shannon measures such as Havrda & Charvat’s entropy, which is commonly used in gray level image analysis in many types of images such as satellite grayscale images. The proposed edge detection performance is compared to the previous classic methods, such as Roberts, Prewitt, and Sobel methods. Numerical results underline the robustness of the presented approach and different applications are shown. 展开更多
关键词 MULTI-THREsHOLD EDGE Detection MEAsURE entropy Havrda & Charvat’s entropy
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The “Dead Universe” Theory: Natural Separation of Galaxies Driven by the Remnants of a Supermassive Dead Universe
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作者 Joel Almeida 《Natural Science》 2024年第6期65-101,共37页
This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This per... This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This perspective challenges the conventional Big Bang theory, particularly concerning dark matter, the expansion of the universe, and the interpretation of phenomena such as gravitational waves. 展开更多
关键词 Dead Universe Theory Heat Death of the Universe Big Bang Theory Universe’s Ultimate Fate Universe Expansion Big Freeze Universe Cosmological Models End of Universe Theories Natural Galaxy Drift Future of the Universe Universe Cooling Down Cosmology and entropy
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