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关于矩阵多项式Jordan标准形刻画
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作者 任芳国 王甜甜 《高等数学研究》 2024年第1期18-21,117,共5页
本文利用矩阵运算、矩阵相似关系及矩阵的秩,深化了Jordan矩阵的性质,并在此基础上刻画了矩阵Jordan标准形中Jordan块的个数及阶数,最后讨论了矩阵多项式Jordan标准形,充实了高等代数中Jordan标准形的结果.
关键词 jordan矩阵 矩阵相似关系 矩阵的秩 矩阵多项式
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Formation Mechanisms of Some Features in Siliceous Upper Cretaceous-Lower Tertiary Beds of Jordan-Undulations, Geodes, Boudinages
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作者 Elias Salameh Hani Khoury 《Open Journal of Geology》 CAS 2024年第4期569-577,共9页
Geode, boudinage, and undulation structures are widely distributed in the siliceous beds of the Upper Cretaceous/Tertiary rocks in Jordan. Their formation was attributed to tectonic forces, syngenetic processes, organ... Geode, boudinage, and undulation structures are widely distributed in the siliceous beds of the Upper Cretaceous/Tertiary rocks in Jordan. Their formation was attributed to tectonic forces, syngenetic processes, organic disintegration processes, subaquatic gliding, compaction and settlement, and meteoritic impacts. In this work, the structural features in the siliceous beds of Jordan are attributed to an interplay of load and directed pressures, and mineralogical transformation processes (opal-A to opal-CT to quartz), governed by pH changes. Tectonic directed pressure was acting in an ESE-WSW direction and is common in the silicified limestone of Upper Cretaceous. 展开更多
关键词 UNDULATIONS Geodes Boudinages Opal-A Porcelanite Chert Transformations pH Changes Stress Fields jordan
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Assessment of Heavy Metals Contamination of Topsoil and Street Dust around Cement Factory in Southern Jordan
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作者 Omar Ali Al-Khashman Alia Omar Al-Khashman +2 位作者 Navasingh Rajesh Jesudoss Hynes Hani M. Alnawafleh Pitchumani Shenbaga Velu 《Journal of Environmental Protection》 2024年第6期672-696,共25页
Evaluation of assessment of the metal processes governing the metals distribution in soil and dust samples is very significant and protects the health of human and ecological system. Recently, special attention has gi... Evaluation of assessment of the metal processes governing the metals distribution in soil and dust samples is very significant and protects the health of human and ecological system. Recently, special attention has given to the assessment of metals pollution impact on soil and dust within industrial areas. This study aims to assess the metal contamination levels in the topsoil and street dust around the cement factory in Qadissiya area, southern Jordan. The levels of seven metals (namely Fe, Zn, Cu, Pb, Cr, Cd, and Mn) were analyzed using Flame Atomic Absorption Spec-trophotometer (FAAS) to monitor, evaluate, and to compare topsoil and road dust pollution values of metals of the different types of urban area. The physicochemical parameters which believed to affect the mobility of metals in the soil of the study area were determined such as pH, EC, TOM, CaCO3 and CEC. The levels of metal in soil samples are greater on the surface but decrease in the lower part as a result of the basic nature of soil. The mean values of the metals in soil can be arranged in the following order: Zn > Pb > Mn > Fe > Cu > Cr > Cd. The relatively high concentration of metals in the soil sample was attributed to anthropogenic activities such as traffic emissions, cement factory and agricultural activities. Correlation coefficient analysis and the spatial distribution of indices and the results of statistical analysis indicate three groups of metals: Fe and Mn result by natural origin, Zn, Pb, Cu and Zn result by anthropogenic origin (mainly motor vehicle traffic and abrasion of tires) while Cd is mixed origin. The higher content level values of metals of anthropogenic source in soil samples indicate that it is a source of contamination of air in the studied area. . 展开更多
关键词 Cement Dust Heavy Metals Contamination Risk Assessment Statistical Analysis jordan
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The Need for International Cooperation between Israel and Other Middle East Nations to Protect the Jordan River Landscape
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作者 Kenneth Ray Olson 《Open Journal of Soil Science》 2024年第5期283-307,共25页
The Jordan River, also referred to as Nahr Al Sharieat in Arabic, is a long river in the Middle East that flows from north to south through the Sea of Galilee to the Dead Sea. The Jordan River is bordered by the Golan... The Jordan River, also referred to as Nahr Al Sharieat in Arabic, is a long river in the Middle East that flows from north to south through the Sea of Galilee to the Dead Sea. The Jordan River is bordered by the Golan Heights and the Hashemite Kingdom of Jordan in the east and by Israel and the Palestinian West Bank (Judea and Samaria) in the west. Soil tunnels, including those in the Jordan River watershed and on the Israel, Syria, and Lebanon borders, have a long history of use for warfare, as invasion pathways, smuggling, and storage of rockets, missiles and ordnance and are causes of serious political tension between the countries. Soil tunnel construction and destruction often has adverse environmental and human health impacts in the Jordan River landscape. Due to agricultural wastes, the discharge of untreated sewage, and diversion of saline springs into the river water there has been serious deterioration in the water quality in the lower courses of the Jordan River. The primary objective of this research is to encourage the development of a multi-country clean-up, mitigation, and protection plan for the Jordan River. 展开更多
关键词 jordan River jordan Israel Lebanon SYRIA Dead Sea Sea of Galilee Six-Day War Soil Tunnels
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Erosion Rates in Dam Catchments in Jordan—Effects of Topography, Geology, and Urbanizations
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作者 Elias Salameh Hakam Al-Alami Ibraheem Hamdan 《Open Journal of Soil Science》 2024年第5期319-331,共13页
Erosion as a natural process produces soils, which are very important natural resources for the fest land plant- and animal kingdoms. Loss of the soil cover reduces agricultural production, biodiversity, and the role ... Erosion as a natural process produces soils, which are very important natural resources for the fest land plant- and animal kingdoms. Loss of the soil cover reduces agricultural production, biodiversity, and the role of soil as a filter for infiltrating water to replenish the groundwater. It also threatens the food supplies. The knowledge of erosion rates of rocks and terrains is important for developing proactive measures to protect soils from erosion and loss. In this study, erosion rates of catchment areas were calculated based on dams’ catchment extensions and the sediment loads transported by flood flows into dams’ lakes. The study results show that the chemically, via floodwater, transported quantities of materials are negligible compared to the solid materials transported by the water. It calculates erosion rates ranging from 0.013 to 0.212 mm/yr (13 - 212 m/10<sup>6</sup> yr) for the different catchment areas. Erosion rates in Jordan are, generally, higher than those calculated for the different parts of the world ranging from 2.5 to 60 m/10<sup>6</sup> yr. This fact can be explained by the very steep topography, calcareous rock cover of the catchment areas and the barren rock exposures. 展开更多
关键词 Erosion Rates jordan DAMS Sediment Load
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Impact of climate change on water resources in the Yarmouk River Basin of Jordan
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作者 Abdelaziz Q BASHABSHEH Kamel K ALZBOON 《Journal of Arid Land》 SCIE CSCD 2024年第12期1633-1647,共15页
Understanding the impact of climate change on water resources is important for developing regional adaptive water management strategies. This study investigated the impact of climate change on water resources in the Y... Understanding the impact of climate change on water resources is important for developing regional adaptive water management strategies. This study investigated the impact of climate change on water resources in the Yarmouk River Basin(YRB) of Jordan by analyzing the historical trends and future projections of temperature, precipitation, and streamflow. Simple linear regression was used to analyze temperature and precipitation trends from 1989 to 2017 at Irbid, Mafraq, and Samar stations. The Statistical Downscaling Model(SDSM) was applied to predict changes in temperature and precipitation from 2018 to 2100 under three Representative Concentration Pathway(RCP) scenarios(i.e., RCP2.6, RCP4.5, and RCP8.5), and the Soil and Water Assessment Tool(SWAT) was utilized to estimate their potential impact on streamflow at Addasiyia station. Analysis of data from 1989 to 2017 revealed that mean maximum and minimum temperatures increased at all stations, with average rises of 1.62℃ and 1.39℃, respectively. The precipitation trends varied across all stations, showing a significant increase at Mafraq station, an insignificant increase at Irbid station, and an insignificant decrease at Samar station. Historical analysis of streamflow data revealed a decreasing trend with a slope of –0.168. Significant increases in both mean minimum and mean maximum temperatures across all stations suggested that evaporation is the dominant process within the basin, leading to reduced streamflow. Under the RCP scenarios, projections indicated that mean maximum temperatures will increase by 0.32℃ to 1.52℃, while precipitation will decrease by 8.5% to 43.0% throughout the 21st century. Future streamflow projections indicated reductions in streamflow ranging from 8.7% to 84.8% over the same period. The mathematical model results showed a 39.4% reduction in streamflow by 2050, nearly double the SWAT model's estimate under RCP8.5 scenario. This research provides novel insights into the regional impact of climate change on water resources, emphasizing the urgent need to address these environmental challenges to ensure a sustainable water supply in Jordan. 展开更多
关键词 streamflow climate change Soil and Water Assessment Tool(SWAT) Statistical Downscaling Model(SDSM) Yarmouk River Basin jordan
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Public knowledge about and attitudes toward organ donation, and public barriers to donate in Jordan: A cross-sectional study
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作者 Adham Al-Salhi Elham H Othman 《World Journal of Transplantation》 2024年第4期110-122,共13页
BACKGROUND Organ donation is a critical issue that is receiving greater attention worldwide.In Jordan,the public’s knowledge about and attitudes toward organ donation play a significant role in the availability of or... BACKGROUND Organ donation is a critical issue that is receiving greater attention worldwide.In Jordan,the public’s knowledge about and attitudes toward organ donation play a significant role in the availability of organs for transplantation.AIM To assess the public knowledge about and attitudes toward organ donation in Jordan.METHODS A cross-sectional design was used to collect data from 396 Jordanian citizens via an online self-reported questionnaire.RESULTS Overall,396 participants were recruited.Of the entire sample,93.9%of the participants had heard about and had sufficient knowledge about organ donation but they had limited knowledge about brain death.The most common source of information about organ donation was social media networks.Females were found to score significantly higher than males for attitude.Those who had thought about organ donation or registered their names to donate scored signi-ficantly higher in terms of attitudes to donation than their counterparts who had not.The most common reasons for limited organ donation practices in Jordan were a lack of awareness programs and insufficient knowledge in society.CONCLUSION Greater public understanding of organ donation appears to be associated with more positive attitudes toward organ donation.Most participants responded positively regarding their attitude toward organ donation as they believed that this action could give another person a chance to live.Moreover,most agreed that they would donate their organs after their death.Otherwise,the participants had limited general knowledge about brain death,and most had not registered their names to donate their organs.These findings indicate the need for public awareness campaigns and educational programs to encourage more people to become organ donors. 展开更多
关键词 ATTITUDE Barriers jordan KNOWLEDGE Organ donation PUBLIC
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Representations of Hom-Jacobi-Jordan Algebras
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作者 LIU Zhiqing ZHANG Xiufu 《湖州师范学院学报》 2024年第10期7-13,共7页
Some relationships between the representation of Hom-Jacobi-Jordan algebra and that of Jacobi-Jordan algebra are studied.Moreover,by using the notion ofαk-anti-derivation,a property theorem of multiplicative Hom-Jaco... Some relationships between the representation of Hom-Jacobi-Jordan algebra and that of Jacobi-Jordan algebra are studied.Moreover,by using the notion ofαk-anti-derivation,a property theorem of multiplicative Hom-Jacobi-Jordan algebras is also given. 展开更多
关键词 Jacobi-jordan algebra Hom-Jacobi-jordan algebra REPRESENTATION anti-derivation
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The Influence of Information Technology(IT)on Accrual Accounting Adoption:The Case of the Jordanian Public Sector
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作者 Moawiah Awad Alghizzawi Rosnia Masruki 《Journal of Modern Accounting and Auditing》 2024年第2期40-48,共9页
Jordan is one of many countries that intends to reform its public sector by adopting accrual accounting,which is primarily carried out through the International Public Sector Accounting Standards(IPSAS)implementation ... Jordan is one of many countries that intends to reform its public sector by adopting accrual accounting,which is primarily carried out through the International Public Sector Accounting Standards(IPSAS)implementation plan,scheduled to be completed by 2021.Considering the difficulties of adoption,this process cannot be completed without an appropriate Information Technology(IT)system capable of providing the accounting information required for this reform.Therefore,this study aims to examine the influence of IT on accrual accounting adoption in the Jordanian public sector.The study employed the quantitative survey approach.Based on 331 usable questionnaires,the descriptive findings showed that the use of IT in the Jordanian public sector is relevant to daily accounting transactions in general and to accrual accounting in particular.The regression analysis showed a positive,significant relationship between IT use and accrual accounting practice.The IT specialist should be able to understand the needs of public sector in adopting accrual-based accounting.In line with today’s digitalization age,which integrates advanced technologies and numerous techniques,this study suggests that a combination of accounting and IT experts is a value added to sharpen the competitiveness of public sector reform.This study contributes to the extant literature in public sector,concerning the relationship between IT and accrual accounting adoption in the context of Jordan. 展开更多
关键词 public sector accrual accounting adoption information technology jordan
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基于Born-Jordan分布的LFM-BPSK信号的参数估计
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作者 张宏业 舒汀 何劲 《现代雷达》 CSCD 北大核心 2024年第11期22-28,共7页
对线性调频-二进制相位编码(LFM-BPSK)复合调制信号的参数估计,现有方法在低信噪比(SNR)环境下估计精度较低。针对该问题,文中推导出了LFM-BPSK信号的Born-Jordan(BJD)时频分布,分析了LFM-BPSK信号的时频特性,并提出了基于BJD时频分布... 对线性调频-二进制相位编码(LFM-BPSK)复合调制信号的参数估计,现有方法在低信噪比(SNR)环境下估计精度较低。针对该问题,文中推导出了LFM-BPSK信号的Born-Jordan(BJD)时频分布,分析了LFM-BPSK信号的时频特性,并提出了基于BJD时频分布的参数估计算法。首先,该算法在BJD时频变换的基础上使用霍夫变换对LFM-BPSK信号初始频率和调频斜率进行估计,并将二维的BJD时频变换转化为一维时域信号,通过降维后的时域信号求解码元宽度;然后,为了探寻参数估计的理论下界,文中还推导了LFM-BPSK信号参数估计的修正克拉美罗下界(MCRLB);最后,利用蒙特卡洛实验对三个参数进行了测试。仿真实验表明,文中算法在低SNR下的参数估计精度明显优于现有的算法,其性能接近MCRLB。 展开更多
关键词 线性调频-二进制相位编码复合调制信号 参数估计 修正克拉美罗下界 Born-jordan时频分布 蒙特卡洛实验
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The Impact of Transformational Leadership on Commitment to Change Among Jordanian Government Accountant Toward IPSAS Implementation
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作者 Mohammad Abu Zraiq Rosnia Masruki 《Journal of Modern Accounting and Auditing》 2024年第3期73-88,共16页
IPSAS was accepted by Jordan’s government in accordance with worldwide trends.The Jordanian Ministry of Finance launched cash-basis IPSAS in 2015 and planned to implement accrual accounting by January 1,2021.However,... IPSAS was accepted by Jordan’s government in accordance with worldwide trends.The Jordanian Ministry of Finance launched cash-basis IPSAS in 2015 and planned to implement accrual accounting by January 1,2021.However,the commitment to change remains uneven,hindering the full shift.Moving from old accounting processes to new ones is tough.Even then,it hasn’t been implemented,creating a gap due to the difficulty in committing to new accounting standards throughout implementation due to obstacles.Thus,knowing government accountants’issues is essential to applying IPSAS in government accounting.This study examines how transformational leadership affects government accountants’commitment to IPSAS adoption in Jordan’s public sector.This study used a quantitative approach to survey Jordanian Ministry of Finance accountants.The 384-person study had a 78%response rate.Additionally,PLS-SEM was used to confirm variable relationships.Transformational leadership positively predicted IPSAS implementation,according to the study. 展开更多
关键词 IPSAS commitment to change transformational leadership government accountant Ministry of Finance jordan
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δ-Hom-Jordan李超代数的泛中心扩张
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作者 刘思廷 孙冰 《东北师大学报(自然科学版)》 CAS 北大核心 2024年第3期5-10,共6页
对δ-Hom-Jordan李超代数的泛中心扩张理论进行了研究,得出两个δ-Hom-Jordan李超代数的中心扩张的复合并不是中心扩张,从而引进了α-中心扩张的定义,进而定义泛α-中心扩张,并且构造出δ-Hom-Jordan李超代数的泛中心扩张.
关键词 泛中心扩张 泛α-中心扩张 δ-Hom-jordan李超代数
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Jordan李代数的分解与Frattini理论 被引量:5
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作者 温启军 钱玲 陈良云 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2010年第4期12-16,共5页
证明了中心为零的Jordan李代数能够分解成不可分解理想的直和,这种分解在不计理想次序的前提下是唯一的,并运用Jordan李代数的Engel定理,得到了Jordan李代数的Frattini子代数的若干性质和幂零Jordan李代数的几个判定方法.
关键词 jordan李代数 Engel定理 分解唯一性 Frattini理论
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二次矩阵广义Jordan积秩的不变性 被引量:4
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作者 吕洪斌 杨忠鹏 +1 位作者 陈梅香 冯晓霞 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2017年第6期1416-1424,共9页
通过给出二次矩阵与二次多项式的互为确定关系,利用矩阵变换得到了二次矩阵广义Jordan积秩的不变性及一种新的与二次矩阵相关的秩等式,所得结果概括并推广了关于(数量)幂等矩阵、(数量)对合矩阵等秩等式的相关结果.
关键词 二次矩阵 矩阵jordan 不变性
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Jordan李代数的Engel定理及其应用 被引量:4
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作者 钱玲 周佳 陈良云 《数学年刊(A辑)》 CSCD 北大核心 2012年第5期517-526,共10页
证明了有限维Jordan李代数的Engel定理,并应用它得到了Jordan李代数的Cartan子代数的若干性质.
关键词 jordan李代数 Engel定理 CARTAN子代数 幂零性
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Jordan三系的次理想的几个性质(英文) 被引量:3
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作者 张知学 董磊 《河北大学学报(自然科学版)》 CAS 2002年第3期215-218,共4页
首先给出了Jordan三元系的次理想的定义与Jordan三元系的次理想的几条简单性质 ,举例说明了次理想与理想是 2个不同的概念 .然后 ,对一类重要的Jordan三元系———正则Jordan三元系 ,证明了它的次理想成为理想的几个充分条件 .
关键词 jordan三元系 次理想 正则jordan三元系 充分条件
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三角代数上的Jordan-triple初等映射及Jordan同构 被引量:3
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作者 魏妙 张建华 《纺织高校基础科学学报》 CAS 2009年第2期193-197,共5页
设U是三角代数,V为任意代数,证明了若映射M:U→V,M*:V→U为满射,并且满足Jordan-trip le初等映射的形式,则M,M*可加.并进一步讨论了映射M,M*在什么条件下具有Jordan同构形式.
关键词 三角代数 jordan—triple初等映射 可加性 jordan同构
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球面栅格空间中的Jordan曲线性质及其拓扑矛盾分析 被引量:3
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作者 侯妙乐 赵学胜 陈军 《武汉大学学报(信息科学版)》 EI CSCD 北大核心 2006年第2期148-151,共4页
定义了球面栅格空间的拓扑元素,给出球面栅格空间中邻近、连通和空间目标的内部、边界和外部等空间目标的拓扑定义及形式化描述,讨论了Jordan曲线在球面栅格空间中的性质及由此引起的拓扑矛盾。
关键词 全球离散格网 球面栅格空间 3连通 12连通 jordan曲线 拓扑矛盾
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含幂等元的环上的Jordan导子的刻画—在零点Jordan可导的可加映射 被引量:4
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作者 安润玲 侯晋川 《数学年刊(A辑)》 CSCD 北大核心 2010年第4期463-474,共12页
设A为包含非平凡幂等元且有单位的环(或代数),δ:A→A是可加(或线性)映射.称δ在零点Jordan可导,若δ(A)B+Aδ(B)+δ(B)A+Bδ(A)=0对任意满足AB+BA=0的A,B∈A成立.在一定条件下,证明了δ在零点Jordan可导当且仅当存在... 设A为包含非平凡幂等元且有单位的环(或代数),δ:A→A是可加(或线性)映射.称δ在零点Jordan可导,若δ(A)B+Aδ(B)+δ(B)A+Bδ(A)=0对任意满足AB+BA=0的A,B∈A成立.在一定条件下,证明了δ在零点Jordan可导当且仅当存在可加Jordan导子τ,使得δ(A)=τ(A)+δ(I)A对任意的A∈A成立.利用此结论,完全刻画了因子von Neumann代数上在零点Jordan可导的可加映射.此外,还刻画了一般von Neumann代数和C~*代数上在零点Jordan可导的有界线性映射. 展开更多
关键词 jordan可导点 von NEUMANN代数 C~*代数
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基于Laplace矩阵Jordan型的复杂网络聚类算法 被引量:1
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作者 牛建伟 戴彬 +2 位作者 童超 霍冠英 彭井 《通信学报》 EI CSCD 北大核心 2014年第3期11-21,共11页
在目前复杂网络聚类算法中,基于Laplace特征值的谱聚类方法具有严密的数学理论和较高的精度,但受限于该方法对簇结构数量、规模等先验知识的依赖,难以实际应用。针对这一问题,基于Laplace矩阵的Jordan型变换,提出了一种先验知识的自动... 在目前复杂网络聚类算法中,基于Laplace特征值的谱聚类方法具有严密的数学理论和较高的精度,但受限于该方法对簇结构数量、规模等先验知识的依赖,难以实际应用。针对这一问题,基于Laplace矩阵的Jordan型变换,提出了一种先验知识的自动获取方法,实现了基于Jordan矩阵特征向量的初始划分。基于Jordan型特征值定义了簇结构的模块化密度函数,并使用该函数和初始划分结果完成了高精度聚类算法。该算法在多个数据集中的实验结果表明,与目前主流的Fast-Newman算法、Girvan-Newman算法相比,基于Laplace矩阵Jordan型聚类算法在不依赖先验知识的情况下,实现了更高的聚类精度,验证了先验知识获取方法的有效性和合理性。 展开更多
关键词 复杂网络 聚类算法 LAPLACE矩阵 jordan 先验知识获取
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