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Rebuilding the theory of isotope fractionation for evaporation of silicate melts under vacuum condition

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Acta Geochimica 2024年第4期43卷 661-676页

作者： jie Wang yun liu Research Center for Planetary Science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China CAS Center for Excellence in Comparative Planetology Hefei 230026China

Isotope eff ects are pivotal in understanding silicate melt evaporation and planetary accretion *** on the Hertz-Knudsen equation,the current theory often fails to predict observed isotope fractionations of laboratory experiments due to its oversimplified ***,we point out that the Hertz-Knudsen-equation-based theory is incomplete for silicate melt evaporation cases and can only be used for situations where the vaporized species is identical to the one in the *** propose a new model designed for silicate melt evaporation under *** model considers multiple steps including mass transfer,chemical reaction,and *** derivations reveal a kinetic isotopic fractionation factor(KIFF orα)αour model=[m(^(1)species)/m(^(2)species)]^(0.5),where m(species)is the mass of the reactant of reaction/nucleation-limiting step or species of diffusion-limiting step and superscript 1 and 2 represent light and heavy isotopes,*** model can eff ectively reproduce most reported KIFFs of laboratory experiments for various elements,i.e.,Mg,Si,K,Rb,Fe,Ca,and ***,the KIFF-mixing model referring that an overall rate of evaporation can be determined by two steps jointly can account for the eff ects of low P_(H2)pressure,composition,and *** addition,we find that chemical reactions,diffusion,and nucleation can control the overall rate of evaporation of silicate melts by using the fitting slope in ln(−ln f)versus ln(t).Notably,our model allows for the theoretical calculations of parameters like activation energy(E_(a)),providing a novel approach to studying compositional and environmental eff ects on evaporation processes,and shedding light on the formation and evolution of the proto-solar and Earth-Moon systems.

关键词： Evaporation Kinetic isotopic fractionation Chemical kinetics Hertz-Knudsen equation CAIS

Reverse-trace routing scheme in content centric networking

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The Journal of China Universities of Posts and Telecommunications 2013年第5期20卷 22-29页

作者： ZHANG Yan HUANG Tao liu Jiang CHEN Jian-ya liu yun-jie Key Laboratory of Universal Wireless Communications of Ministry of Education Beijing University of Posts and Telecommunications

Content center networking （CCN） is one of the most promising future network architectures. Current researches on CCN routing scheme mainly focus on finding the best single routing path, which may induce to low usage of the in-network caches. In order to overcome this problem, a reverse trace routing （RTR） scheme is proposed in this paper, in which Interest packet is sent to the edge-cache along with the reverse trace of the corresponding former Data packet. By doing this, the Interest packets will have better chances to be routed to the promising in-network caches before reaching the source server, which could increase the in-network hit rate, while decrease the server stress. The simulation results show clearly that the RTR scheme decreases the source server load, while reducing the mean hops of entire data retrieval process under certain circumstances.

关键词： CCN routing RTR next face table (NFT)

New algorithm for hub-and-spoke topological virtual networks embedding problem

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 55-61页

作者： liu Jiang HUANG Tao CHEN Jian-ya liu yun-jie LÜ Bo Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

The virtual network embedding/mapping problem is a core issue of the network virtualization. It＇s mainly concerned with how to map virtual network requests to the substrate network efficiently. Previous researches mainly focus on developing heuristic algorithms for general topology virtual network request. In this paper, we propose a new algorithm for the hub-and-spoke （HAS） topology virtual request. The characters of the HAS topology are exploited to develop the new algorithm. The simulation results show that the new algorithm greatly enhances the performance of revenue/cost （R/C） ratio while the HAS topology request arrives.

关键词： virtual network embedding general topology HAS topology

Fast convergence caching replacement algorithm based on dynamic classification for content-centric networks

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The Journal of China Universities of Posts and Telecommunications 2013年第5期20卷 45-50页

作者： FANG Chao HUANG Tao liu Jiang CHEN Jian-ya liu yun-jie Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications

One of the key research fields of content-centric networking （CCN） is to develop more efficient cache replacement policies to improve the hit ratio of CCN in-network caching. However, most of existing cache strategies designed mainly based on the time or frequency of content access, can not properly deal with the problem of the dynamicity of content popularity in the network. In this paper, we propose a fast convergence caching replacement algorithm based on dynamic classification method for CCN, named as FCDC. It develops a dynamic classification method to reduce the time complexity of cache inquiry, which achieves a higher caching hit rate in comparison to random classification method under dynamic change of content popularity. Meanwhile, in order to relieve the influence brought about by dynamic content popularity, it designs a weighting function to speed up cache hit rate convergence in the CCN router. Experimental results show that the proposed scheme outperforms the replacement policies related to least recently used （LRU） and recent usage frequency （RUF） in cache hit rate and resiliency when content popularity in the network varies.

关键词： CCN cache replacement policy dynamic classification fast convergence category popularity

Interference of human's ankle to the channel characteristics of near surface WUSN

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 36-42页

作者： LI Li WU Wei CHEN Jian-ya liu yun-jie State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

Because of its potential applications in agriculture, environment monitoring and so on, wireless underground sensor network（WUSN） has been researched more and more extensively in recent years. The main and most important difference of WUSN to terrestrial wireless sensor network（WSN） is the channel characteristics, which determines the design methodology of it. In this paper, the propagation character of electromagnetic（EM） wave in the near surface WUSN is analyzed, as well as the path loss model of it is given. In addition, the influence of human＇s ankle to the channel characteristics of near surface WUSN is investigated by electromagnetic theory analysis, simulation and experiment. A novel path loss model of near surface WUSN which takes the interference of human＇s ankle into consideration is proposed. It is verified that the existing of human above the WUSN system may cause additional attenuation to the signal of near surface WUSN which propagates as lateral wave along the ground. Moreover, the relation of the attenuation and operating frequency is deduced, which gives a reference to extend the frequency band applied in WUSN.

关键词： WUSN lateral wave human tissue path loss model EM wave attenuation

Hierarchical network with diversified customer edge access

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 104-110,117页

作者： LI Rui HUANG Tao CHEN Jian-ya liu yun-jie Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China China Unicorn Beijing 100140 China

The Internet today originates from the advanced research project agency network （ARPANET） and evolves constantly during the past years. However, with incremental ＇patches＇ on the Internet, the current network architecture faces many problems which are too difficult to solve. In the light of recent interest in re-designing the Internet, the separation of core network and customer edge network, and the separation of identifier and locator receive wide consensus among scientists. We follow this direction and propose a new hierarchical network with diversified customer edge access （HNDCE） in this paper. We use switching addresses, routing addresses and identifiers to implement a true core/edge and locator/identifier split. In the core network, hierarchical switching addresses combined with tree topology makes routing replaced by switching. The Viliant load-balancing （VLB） structure is used here to compensate the topology＇s reliability and scalability. In the customer edge network, the split of locator and identifier makes it possible to deploy various routing schemes and new services. Hierarchical mapping system is also designed to support this new architecture.

关键词： hierarchical, identification, switching separation, VLB

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物联网中的分布式能源管理与优化

In-network caching for energy efficiency in content-centric networking

科学与信息化 2024年第2期 31-33页

作者：李敬刘运杰钟连鑫泰山科技学院山东泰安 271000

物联网的快速发展和能源管理的重要性使得分布式能源管理与优化成为一个备受关注的领域.本文探讨了分布式能源管理与优化的关键技术,包括能源数据采集与分析技术、能源调度与优化算法以及分布式能源管理系统的设计与实施方法.通过案例... 详细信息

物联网的快速发展和能源管理的重要性使得分布式能源管理与优化成为一个备受关注的领域.本文探讨了分布式能源管理与优化的关键技术,包括能源数据采集与分析技术、能源调度与优化算法以及分布式能源管理系统的设计与实施方法.通过案例分析和研究,验证了物联网在分布式能源管理与优化中的效果和效益,并提出了改进和优化的措施.

关键词：物联网分布式能源管理优化

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The Journal of China Universities of Posts and Telecommunications 2014年第4期21卷 25-31页

作者： WANG Guo-qing HUANG Tao liu Jiang XIE Ren-chao liu yun-jie State Key Laboratory of Networking and Switching Technology School of Telecommunication EngineeringBeijing University of Posts and Telecommunications

Recently, Internet energy efficiency is paid more and more attention. New Internet architectures with more energy efficiency were proposed to promote the scalability in energy consumption. The eontent-eentrie networking （CCN） proposed a content-centric paradigm which was proven to have higher energy efficiency. Based on the energy optimization model of CCN with in-network caching, the authors derive expressions to tradeoff the caching energy and the transport energy, and then design a new energy efficiency cache scheme based on virtual round trip time （EV） in CCN. Simulation results show that the EV scheme is better than the least recently used （LRU） and popularity based cache policies on the network average energy consumption, and its average hop is also much better than LRU policy.

关键词： CCN EV cache scheme energy efficiency

Modeling in-network caching and bandwidth sharing performance in information-centric networking

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The Journal of China Universities of Posts and Telecommunications 2013年第2期20卷 99-105页

作者： WANG Guo-qing HUANG Tao liu Jiang CHEN Jian-ya liu yun-jie Key Laboratory of Universal Wireless Communications of Ministry of Education Beijing University of Posts and Telecommunications School of Telecommunication Engineering Beijing University of Posts and Telecommunications

Information-centric networking （ICN） proposes a content-centric paradigm which has some attractive advantages, such as network load reduction, low dissemination latency, and energy efficiency. In this paper, based on the analytical model of ICN with receiver-driven transport protocol employing least-recently used （LRU） replacement policy, we derive expressions to compute the average content delivery time of the requests＇ arrival sequence of a single cache, and then we extend the expressions to a cascade of caches＇ scenario. From the expressions, we know the quantitative relationship among the delivery time, cache size and bandwidth. Our results, analyzing the trade-offs between performance and resources in ICN, can be used as a guide to design ICN and to evaluation its performance.

关键词： ICN LRU miss probability content delivery time