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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Average Path Length of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Xiaoxuan Li Yangqi 《Journal of Traffic and Transportation Engineering》 2024年第1期11-22,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the node average path length of China aviation network in 1988,1994,2001,2008 and 2015 was calculated.Through regression analysis,it was found that the node degree had a logarithmic relationship with the average length of node path,and the two parameters of the logarithmic relationship had linear evolutionary trace.Key word:China aviation network,complex network,node degree,average length of node path,logarithmic relationship,evolutionary trace. 展开更多
关键词 China aviation network complex network node degree average length of node path logarithmic relationship evolutionary trace.
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ANALYSIS ON GRAY NODES AND GRAYNESS DEGREE IN COMPLEX NETWORK 被引量:1
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作者 崔博 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期125-130,共6页
Based on the theory of complex network and gray system, the sugesstion that there exist two types of gray nodes in complex networks, Gray Node I and Gray Node II, is concluded. The first one refers to the existent unk... Based on the theory of complex network and gray system, the sugesstion that there exist two types of gray nodes in complex networks, Gray Node I and Gray Node II, is concluded. The first one refers to the existent unknown gray nodes, and the second the evolution gray nodes. The relevant definitions are also given. Further- more, grayness degree in complex networks is described and divided into two forms--the relative grayness degree (RGD) and the absolute grayness degree (AGD), which are proved respectively. 展开更多
关键词 gray system complex network gray nodes grayness degree
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Small World Properties Generated by a New Algorithm Under Same Degree of All Nodes 被引量:8
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作者 LI Yong FANG Jin-Qing LIU Qiang LIANG Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期950-954,共5页
Based on the model of the same degree of all nodes we proposed before, a new algorithm, the so-called “spread all over vertices” (SAV) algorithm, is proposed for generating small-world properties from a regular ri... Based on the model of the same degree of all nodes we proposed before, a new algorithm, the so-called “spread all over vertices” (SAV) algorithm, is proposed for generating small-world properties from a regular ring lattices. During randomly rewiring connections the SAV is used to keep the unchanged number of links. Comparing the SAV algorithm with the Watts-Strogatz model and the “spread all over boundaries” algorithm, three methods can have the same topological properties of the small world networks. These results offer diverse formation of small world networks. It is helpful to the research of some applications for dynamics of mutual oscillator inside nodes and interacting automata associated with networks. 展开更多
关键词 small world network the same degree of all nodes in the network “spread all over vertices”algorithm average shortest path length average clustering coefficient
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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Nearest Neighbor Average Degree of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Zhang Xiaoxuan 《Journal of Traffic and Transportation Engineering》 2023年第4期159-171,共13页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the relationship between the node degree and the nearest neighbor average degree and its evolution trace of Chi... In order to reveal the complex network characteristics and evolution principle of China aviation network, the relationship between the node degree and the nearest neighbor average degree and its evolution trace of China aviation network in 1988, 1994, 2001, 2008 and 2015 were studied. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network. According to the statistical data, the node nearest neighbor average degree of China aviation network in 1988, 1994, 2001, 2008 and 2015 was calculated. Through regression analysis, it was found that the node degree had a negative exponential relationship with the nearest neighbor average degree, and the two parameters of the negative exponential relationship had linear evolution trace. 展开更多
关键词 China aviation network complex network node degree nearest neighbor average degree negative exponential relationship evolution trace.
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Mining and Ranking Important Nodes in Complex Network by K-Shell and Degree Difference 被引量:1
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作者 Jianpei Zhang Hui Xu +1 位作者 Jing Yang Lijun Lun 《国际计算机前沿大会会议论文集》 2018年第1期28-28,共1页
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Degree-Based Probabilistic Caching in Content-Centric Networking 被引量:1
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作者 Meng Zhang Jianqiang Tang +2 位作者 Ying Rao Hongbin Luo Hongke Zhang 《China Communications》 SCIE CSCD 2017年第3期158-168,共11页
Content-Centric Networking is a novel future network architecture that attracts increasing research interests in recent years. In-network caching has been regarded as a prominent feature of Content-Centric Networking ... Content-Centric Networking is a novel future network architecture that attracts increasing research interests in recent years. In-network caching has been regarded as a prominent feature of Content-Centric Networking since it is able to reduce the network traffic, alleviate the server bottleneck and decrease the user access latency. However, the CCN default caching scheme results in a high caching redundancy, causing an urgent need for an efficient caching scheme. To address this issue, we propose a novel implicit cooperative caching scheme to efficiently reduce the caching redundancy and improve the cache resources utilization. The simulation results show that our design achieves a higher hit ratio and a shorter cache hit distance in comparison with the other typical caching schemes. 展开更多
关键词 in-network caching implicit cooperation content-centric networking caching performance node degree
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Research and Analysis of WSN Node Location in Highway Traffic Based on Priority
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作者 Congrong Tang 《Journal of Quantum Computing》 2020年第1期1-9,共9页
With the rapid development of highway transportation in China,intelligent transportation has become an important part of the traffic structure,and wireless sensor networks are also widely used in intelligent transport... With the rapid development of highway transportation in China,intelligent transportation has become an important part of the traffic structure,and wireless sensor networks are also widely used in intelligent transportation.However,in the wireless traffic sensor network,there is a certain error in the positioning of the anchor blind nodes.In the process of tracking the feedback information,the results of determining the position are very different.Based on the maximum degree of tension,the road traffic wireless Research and analysis of blind node location in sensor networks,and propose solutions and measures to reduce monitoring results. 展开更多
关键词 MAXIMUM degree of road traffic WSN blind node positioning order
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取向度对Nd-Fe-B磁体磁性能均匀性的影响 被引量:6
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作者 邹光荣 傅恒志 +2 位作者 胡世平 姜战军 王文照 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2000年第3期149-152,共4页
用数理统计方法研究了粉末烧结 Nd- Fe- B永磁体磁性能的均匀性。分析发现 ,粉末取向度对均匀性有很大影响 ,随装填密度增加 ,取向度变小 ,磁性减弱 ,分布的离散度变宽。磁体磁通量的分布受成分、取向磁场和密度等多种随机因素的影响 ,... 用数理统计方法研究了粉末烧结 Nd- Fe- B永磁体磁性能的均匀性。分析发现 ,粉末取向度对均匀性有很大影响 ,随装填密度增加 ,取向度变小 ,磁性减弱 ,分布的离散度变宽。磁体磁通量的分布受成分、取向磁场和密度等多种随机因素的影响 ,统计结果比较好地服从正态分布。 展开更多
关键词 nd-FE-B 取向度 磁性能均匀性 永磁体
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影响烧结NdFeB磁性能因素的研究 被引量:6
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作者 张哲旭 孙继兵 +2 位作者 崔春翔 杨薇 郭平 《热加工工艺》 CSCD 北大核心 2008年第10期1-4,共4页
研究了烧结NdFeB磁体中富钕相形态、主相晶粒度和初始粉末颗粒的形态等因素对磁性能的影响。结果表明,只有当富钕相均匀分布,且与主相晶粒边界形状相适应时才能起到提高NdFeB烧结磁体磁性能的作用。介绍了取向度的计算以及对磁性能的影... 研究了烧结NdFeB磁体中富钕相形态、主相晶粒度和初始粉末颗粒的形态等因素对磁性能的影响。结果表明,只有当富钕相均匀分布,且与主相晶粒边界形状相适应时才能起到提高NdFeB烧结磁体磁性能的作用。介绍了取向度的计算以及对磁性能的影响,指出只采用(105)与(006)衍射峰的比值确定NdFeB的取向度不合理,想要获得更精确的取向度应该考虑更多的错取向峰。 展开更多
关键词 烧结ndFEB磁体 富钕相 取向度 磁性能
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Nd-YAG激光辅助治疗牙周-牙髓联合病变的临床疗效观察 被引量:19
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作者 李晓丽 董坚 +1 位作者 刘林 丁芳 《中华老年口腔医学杂志》 2020年第2期81-85,共5页
目的:研究掺钕钇铝石榴石固体(Nd-YAG)激光辅助治疗牙周-牙髓联合病变的临床效果。方法:选取2016年1月~2019年6月我院收治的84例牙周-牙髓联合病变患者,按随机数字表法分为两组,各42例。对照组给予根管治疗和牙周基础治疗,观察组辅助应... 目的:研究掺钕钇铝石榴石固体(Nd-YAG)激光辅助治疗牙周-牙髓联合病变的临床效果。方法:选取2016年1月~2019年6月我院收治的84例牙周-牙髓联合病变患者,按随机数字表法分为两组,各42例。对照组给予根管治疗和牙周基础治疗,观察组辅助应用Nd-YAG激光治疗。比较两组根管填充1d、7d后视觉模拟评分法(VAS)评分、治疗后6个月总有效率、菌斑指数(PLI)、牙周探诊深度(PD)、牙周附着水平(CAL)、改良出血指数(m BI)。结果:观察组总有效率高于对照组,根管填充1d后VAS评分、PD、CAL及m BI低于对照组(P<0.05)。结论:Nd-YAG激光辅助治疗牙周-牙髓联合病变,可减轻患者疼痛,提高舒适度,促进病变恢复,保留患牙,疗效显著。 展开更多
关键词 nd-YAG激光 牙周-牙髓联合病变 疼痛程度 舒适度 炎症反应
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烧结Nd-Fe-B取向度的研究 被引量:5
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作者 何叶青 熊科 +3 位作者 韩丽萍 高学绪 张茂才 周寿增 《功能材料》 EI CAS CSCD 北大核心 1999年第5期470-472,共3页
提出了一种用普通X射线衍射谱定量测量烧结Nd-Fe-B磁体取向度的简单易行的新方法,并与用10~12T强脉冲磁场测量的Br/Js和(Br//→Br)/Br//值进行了比较。通过实验证明,单用X射线衍射谱中(105)与(006)晶面的相对衍射强度... 提出了一种用普通X射线衍射谱定量测量烧结Nd-Fe-B磁体取向度的简单易行的新方法,并与用10~12T强脉冲磁场测量的Br/Js和(Br//→Br)/Br//值进行了比较。通过实验证明,单用X射线衍射谱中(105)与(006)晶面的相对衍射强度比I(015)/I(006)来讲估Nd-Fe-B磁体的取向度是不妥的。为提高在金属模压工艺条件下的取向度,应加大取向外磁场或者采取减小磁粉与模具之间摩擦力的措施。 展开更多
关键词 烧结 取向度 橡皮模压方法 永磁材料
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添加Dy_2O_3对烧结Nd-Fe-B磁体结构与性能的影响 被引量:2
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作者 刘湘涟 《磁性材料及器件》 CAS CSCD 北大核心 2011年第6期35-37,75,共4页
应用常规粉末冶金工艺制备(Pr-Nd)32Gd0.6FebalNb0.55Cu0.20Al0.45B1.12+x%Dy2O3烧结磁体,分析了添加Dy2O3对其磁性能、抗弯强度、显微组织以及取向度的影响。结果表明,适量添加Dy2O3,使内禀矫顽力显著提高,同时剩磁出现一定程度的下降... 应用常规粉末冶金工艺制备(Pr-Nd)32Gd0.6FebalNb0.55Cu0.20Al0.45B1.12+x%Dy2O3烧结磁体,分析了添加Dy2O3对其磁性能、抗弯强度、显微组织以及取向度的影响。结果表明,适量添加Dy2O3,使内禀矫顽力显著提高,同时剩磁出现一定程度的下降。Dy2O3添加数量大于1.2%之后,磁体取向度明显提高,而其显微组织中则存在比较多的孔隙,抗弯强度开始大幅度降低。 展开更多
关键词 烧结nd-FE-B磁体 Dy2O3添加 显微组织 取向度 磁性能 抗弯强度
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烧结过程、粉末粒度及有效稀土含量对Nd-Fe-B永磁材料取向度的影响 被引量:3
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作者 刘湘涟 《磁性材料及器件》 CAS CSCD 2007年第2期26-29,共4页
选择不同设计成分与不同平均粒度的合金粉末,应用粉末冶金工艺制备烧结Nd-Fe-B永磁材料样品,分析了烧结过程、粉末粒度以及有效稀土含量对材料取向度的影响。实验结果表明,当烧结温度为1323K、1353K和1383K时,随着烧结保温时间的延长,... 选择不同设计成分与不同平均粒度的合金粉末,应用粉末冶金工艺制备烧结Nd-Fe-B永磁材料样品,分析了烧结过程、粉末粒度以及有效稀土含量对材料取向度的影响。实验结果表明,当烧结温度为1323K、1353K和1383K时,随着烧结保温时间的延长,材料取向度有着明显提高的趋势;有效稀土含量高或者合金粉末粒度大,皆不利于Nd-Fe-B永磁材料取向度的改善。 展开更多
关键词 nd-FE-B永磁材料 烧结 取向度 有效稀土含量 粉末粒度
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Nd-Fe-B 烧结磁体的高性能化 被引量:4
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作者 吴安国 《磁性材料及器件》 CAS CSCD 1998年第4期12-18,共7页
简述了高性能Nd-Fe-B烧结磁体对微结构和相组成的要求;综述了各种因素(添加元素、磁粉和晶粒的粒度、定向度、含氧量)对Nd-Fe-B烧结磁体的影响;最后讨论了Nd-Fe-B磁体的高温稳定性。
关键词 烧结磁体 添加元素 粒度 定向度 永磁合金 性能
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(Nd,Dy)_(13.5)Fe_(80)B_(6.5)合金铸片的微结构研究
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作者 刘汉强 高汝伟 +1 位作者 王标 韩广兵 《中国稀土学报》 CAS CSCD 北大核心 2003年第4期403-405,共3页
研究了铸片工艺制备的(Nd,Dy)13.5Fe80B6.5铸片的微结构。结果表明:铸片主要由2∶14∶1相片状晶组成且存在明显的择优取向,晶粒沿[00l]方向择优生长;取向度随轮速改变发生明显的变化,在v=1.5~2m·s-1时取最大值。当v=2m·s-1... 研究了铸片工艺制备的(Nd,Dy)13.5Fe80B6.5铸片的微结构。结果表明:铸片主要由2∶14∶1相片状晶组成且存在明显的择优取向,晶粒沿[00l]方向择优生长;取向度随轮速改变发生明显的变化,在v=1.5~2m·s-1时取最大值。当v=2m·s-1时铸片由厚度约3μm、且被0.2~0.5μm的富Nd相薄层隔开的2∶14∶1相片状晶组成,铸片中不存在α Fe枝状晶。 展开更多
关键词 凝聚态物理 铸片 取向度 nd-FE-B 微观结构 晶粒 稀土
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液相烧结对Nd-Fe-B粉末压坯及磁体取向度的影响 被引量:3
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作者 何叶青 王震西 +2 位作者 周寿增 张臻蓉 韩宝善 《中国稀土学报》 CAS CSCD 北大核心 2003年第4期367-370,共4页
XRD,SEM及MFM观察表明,Nd Fe B粉末压坯在液相烧结过程中同时存在两种影响主相晶粒取向度的机制:烧结过程中大颗粒吞并吸附在其表面的取向不良的小晶粒并择优长大,使磁体的取向度提高;在液相烧结过程中,被液相所包围的主相晶粒的自由转... XRD,SEM及MFM观察表明,Nd Fe B粉末压坯在液相烧结过程中同时存在两种影响主相晶粒取向度的机制:烧结过程中大颗粒吞并吸附在其表面的取向不良的小晶粒并择优长大,使磁体的取向度提高;在液相烧结过程中,被液相所包围的主相晶粒的自由转动,造成磁体的取向度降低。对于取向度较低的DP生坯,烧结中影响Nd Fe B磁体取向度的前一种机制是主导的;而对于取向度较高的振动RIP生坯,烧结过程中后一种机制起主导作用。 展开更多
关键词 凝聚态物理 烧结nd-FE-B 压坯 X射线 取向度 磁力显微镜 稀土
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Circulation system complex networks and teleconnections 被引量:4
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作者 龚志强 王晓娟 +1 位作者 支蓉 冯爱霞 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第7期495-503,共9页
In terms of the characteristic topology parameters of climate complex networks, the spatial connection structural complexity of the circulation system and the influence of four teleconnection patterns are quantitative... In terms of the characteristic topology parameters of climate complex networks, the spatial connection structural complexity of the circulation system and the influence of four teleconnection patterns are quantitatively described. Results of node degrees for the Northern Hemisphere (NH) mid-high latitude (30° N-90°N) circulation system (NHS) networks with and without the Arctic Oscillations (AO), the North Atlantic Oscillations (NAO) and the Pacific-North American pattern (PNA) demonstrate that the teleconnections greatly shorten the mean shortest path length of the networks, thus being advantageous to the rapid transfer of local fluctuation information over the network and to the stability of the NHS. The impact of the AO on the NHS connection structure is most important and the impact of the NAO is the next important. The PNA is a relatively independent teleconnection, and its role in the NHS is mainly manifested in the connection between the NHS and the tropical circulation system (TRS). As to the Southern Hemisphere mid-high latitude (30°S-90°S) circulation system (SHS), the impact of the Antarctic Arctic Oscillations (AAO) on the structural stability of the system is most important. In addition, there might be a stable correlation dipole (AACD) in the SHS, which also has important influence on the structure of the SHS networks. 展开更多
关键词 complex network structural feature circulation system node degree
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A compound objective reconfiguration of distribution networks using hierarchical encoded particle swarm optimization 被引量:3
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作者 WEN Juan TAN Yang-hong +1 位作者 JIANG Lin XU Zu-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第3期600-615,共16页
With the development of automation in smart grids,network reconfiguration is becoming a feasible approach for improving the operation of distribution systems.A novel reconfiguration strategy was presented to get the o... With the development of automation in smart grids,network reconfiguration is becoming a feasible approach for improving the operation of distribution systems.A novel reconfiguration strategy was presented to get the optimal configuration of improving economy of the system,and then identifying the important nodes.In this strategy,the objectives increase the node importance degree and decrease the active power loss subjected to operational constraints.A compound objective function with weight coefficients is formulated to balance the conflict of the objectives.Then a novel quantum particle swarm optimization based on loop switches hierarchical encoded was employed to address the compound objective reconfiguration problem.Its main contribution is the presentation of the hierarchical encoded scheme which is used to generate the population swarm particles of representing only radial connected solutions.Because the candidate solutions are feasible,the search efficiency would improve dramatically during the optimization process without tedious topology verification.To validate the proposed strategy,simulations are carried out on the test systems.The results are compared with other techniques in order to evaluate the performance of the proposed method. 展开更多
关键词 distribution network reconfiguration node importance degree compound objective function hierarchical encoded
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烧结Nd-Fe-B磁体的角度差与取向度
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作者 何若冲 王发立 胡季帆 《功能材料》 EI CAS CSCD 北大核心 2012年第20期2863-2866,共4页
用Helmholtz线圈测量了烧结Nd-Fe-B小立方磁体组合成大组件磁体的总磁矩,实验结果表明,高取向烧结Nd-Fe-B磁体的有效宏观磁矩符合矢量线性叠加原理。烧结Nd-Fe-B磁体的取向度越高磁矩角度差越小,但磁矩角度差小的磁体其取向度不一定高... 用Helmholtz线圈测量了烧结Nd-Fe-B小立方磁体组合成大组件磁体的总磁矩,实验结果表明,高取向烧结Nd-Fe-B磁体的有效宏观磁矩符合矢量线性叠加原理。烧结Nd-Fe-B磁体的取向度越高磁矩角度差越小,但磁矩角度差小的磁体其取向度不一定高。同时利用有限元方法计算了Halbach阵列的磁力线分布。 展开更多
关键词 烧结nd-FE-B磁体 磁矩角度差 取向度
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IT Asset Management of Industrial Automation Systems
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《可编程控制器与工厂自动化(PLC FA)》 2005年第12期29-31,共3页
1. Introduction The installation and administration of large heterogeneous IT infrastructures, for enterprises as well industrial automation systems, are becoming more and more complex and time consuming. The growing ... 1. Introduction The installation and administration of large heterogeneous IT infrastructures, for enterprises as well industrial automation systems, are becoming more and more complex and time consuming. The growing number of interconnections between networks, the development of new intelligent IT devices, and increasingly sophisticated computer hard- 展开更多
关键词 In Man work ABB ndS SNMP WMI node IT Asset Management of Industrial Automation Systems DMTF
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