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Service-Oriented Network Virtualization Architecture for Internet of Things

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China Communications 2016年第9期13卷 163-172页

作者： yongan guo Hongbo Zhu Longxiang Yang College of Telecommunications&Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu Key Lab of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China

As a key technology to realize smart services of Internet of Things（IoT）, network virtualization technology can support the network diversification and ubiquity, and improve the utilization rate of network resources. This paper studies the service-ori- ented network virtualization architecture for loT services. Firstly the semantic description method for loT services is proposed, then the resource representation model and resource management model in the environment of network virtualization are presented. Based on the above models, the service-oriented virtual network architecture for loT is established. Finally, a smart campus system is designed and deployed based on the service-oriented virtual network architecture. Moreover, the proposed architecture and models are verified in experiments.

关键词： Internet of Things network virtualization virtual network resource management virtual network embedding

Smart Service System(SSS)：A Novel Architecture Enabling Coordination of Heterogeneous Networking Technologies and Devices for Internet of Things

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China Communications 2017年第3期14卷 130-144页

作者： yongan guo hongbo zhu longxiang yang college of telecommunications & information engineering nanjing university of posts and telecommunicationsnanjing 210003China

In Internet of Things(IoT), the devices or terminals are connected with each other, which can be very diverse over the wireless networks. Unfortunately, the current devices are not designed to communicate with the collocated devices which employ different communication technologies. Consequently, the communication between these devices will be realized only by using the gateway nodes. This will cause the inefficient use of wireless resources. Therefore, in this paper, a smart service system(SSS) architecture is proposed, which consists of smart service terminal(SST), and smart service network(SSN), to realize the Io T in a general environment with diverse communication networks, devices, and services. The proposed architecture has the following advantages: i) the devices in this architecture cover multiple types of terminals and sensor-actuator devices; ii) the communications network therein is a converged network, and will coordinate multiple kinds of existing and emerging networks. This converged network offers ubiquitous access for various sensors and terminals; iii) the architecture has services and applications covering all smart service areas. It also provides theadaptability to new services and applications. A SSS architecture-based smart campus system was developed and deployed. Evaluation experiments of the proposed smart campus system demonstrate the SSS's advantages over the existing counterparts, and verify the effectiveness of the proposed architecture.

关键词： Internet of Things network architecture clean slate evolutionary approach network heterogeneity reconfiguration

Thermal Stability of a New Ni-Fe-Cr Base Alloy with Different Ti/Al Ratios

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Journal of Materials Science & Technology 2015年第2期31卷 135-142页

作者： Changshuai Wang Tingting Wang Meilin Tan yongan guo Jianting guo Lanzhang Zhou Institute of Metal Research Chinese Academy of Sciences

Influence of Ti/Al ratios on the thermal stability of a new low cost Ni-Fe-Cr base wrought alloy,designed for application at 700℃ in advanced ultra-supercritical coal-fired power plants(700℃A-USC),was investigated both experimentally and thermodynamically. After standard heat treatment,the alloys with different Ti/Al ratios had the same microstructural characteristics. However,compared with the alloys with high Ti/Al ratio,the low Ti/Al ratio can increase the γ’-solvus temperature,decrease γ’ coarsening rate and reduce the temperature range of η phase precipitation. For the alloys with low Ti/Al ratio,the yield strength has no obvious decrease during long-term thermal exposure at 700 and 750℃,but after thermal exposure at 750℃ for 5000 h,the yield strength of the alloys with high Ti/Al ratio obviously decreases due to the η phase precipitation. The influence of h phase on mechanical properties is related with its size. When the h phase is small,it has no obvious influence on mechanical properties,but h phase becomes the crack initiation site with the further growth of η phase. It can be concluded that the decrease in Ti/Al ratio can improve the thermal stability to meet the requirement of 700℃ A-USC coal-fired power plants.

关键词： 700℃ A-USC Ni-Fe-Cr base alloy Thermal stability η

An Exact Virtual Network Embedding Algorithm Based on Integer Linear Programming for Virtual Network Request with Location Constraint

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China Communications 2016年第8期13卷 177-183页

作者： Zeheng Yang yongan guo School of Computer Science and Engineering University of Electronic Science and Technology of China(UESTC) College of Telecommunications and Information Engineering Nanjing University of Posts and Telecommunications

Network virtualization is known as a promising technology to tackle the ossification of current Internet and will play an important role in the future network area. Virtual network embedding(VNE) is a key issue in network virtualization. VNE is NP-hard and former VNE algorithms are mostly heuristic in the *** exact algorithms have been developed in recent years. However, the constraints of exact VNE are only node capacity and link *** on these, this paper presents an exact VNE algorithm, ILP-LC, which is based on Integer Linear Programming(ILP), for embedding virtual network request with location constraints. This novel algorithm is aiming at mapping virtual network request(VNR) successfully as many as possible and consuming less substrate *** topology of each VNR is randomly generated by Waxman model. Simulation results show that the proposed ILP-LC algorithm outperforms the typical heuristic algorithms in terms of the VNR acceptance ratio, at least 15%.

关键词： network virtualization virtual network embedding exact VNE algorithm integer linear Programming location constraint VNR acceptance ratio

Pricing Based Power Control for Inter-Cell UAV-Assisted Vehicle-to-Vehicle Underlay Communication

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China Communications 2019年第1期16卷 57-68页

作者： Qin Wang Ye Chen Shu Yin Lei Tian yongan guo Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications School of Engineering & Computing Sciences New York Institute of Technology College of Overseas Education Nanjing University of Posts and Telecommunications

The high-capacity vehicle-to-vehicle(V2 V) communication provides a promising solution to support ubiquitous media streaming and content sharing among *** extend the V2 V links to multiple cells and manage the inter-cell interference,we proposed an UAV-assisted inter-cell V2 V communication model,in which a shared UAV node is placed in the center of V2 V *** charging the V2 V users underlay spectrum access fee,the cellular network earn profit at the cost of encountering co-channel interference from V2 V links.A Stackelberg game is formulated to model the interactions between the V2 V links and the cellular links,which are the game follower and the leader *** utility functions are maximized in terms of accessing price as well as transmit power of V2 V users and UAV *** evaluations verify that the power-price tradeoff between V2 V network and cellular network has significant potentials to enhance their utility.

关键词： UAV-assisted communication inter-cell V2V Stackelberg game IoT economics

A Study on Service-Oriented Smart Medical Systems Combined with Key Algorithms in the IoT Environment

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China Communications 2019年第9期16卷 235-249页

作者： Shan Lu Anzhi Wang Shenqi Jing Tao Shan Xin Zhang yongan guo Yun Liu Department of Geriatrics the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Department of Health Education the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Engineering Research Center of Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing 210003China

A smart medical service system architecture is proposed in this paper to increase medical resource utilization and improve the efficiency of the medical diagnosis process for complex business scenarios in the Medical Internet of Things(MIoT)*** resource representation model theory,multi-terminal aggregation algorithm,and the resource discovery algorithm based on latent factor model are also studied.A smart medical service system within the IoT environment is then developed,based on the open source *** results using real-world datasets illustrate that the proposed smart medical service system architecture can promote the intelligent and efficient management of medical resources to an extent,and assists in the develop towards digitization,intelligence,and precision in the field of medicine.

关键词： Internet of Things resource representationmodel resource discovery algorithm smart medical service system

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面向物联网服务的资源表示模型研究

南京邮电大学学报（自然科学版） 2019年第1期39卷 24-33页

作者：郭永安王安之南京邮电大学江苏省无线通信重点实验室江苏南京210003

为了解决当前物联网应用系统中存在的资源异构性和海量性问题,基于本体描述模型讨论物联网服务和资源的语义化描述方法,并在服务和资源之间建立相应的映射关系,最终形成一种面向物联网服务的资源统一表示模型。该模型为实现物联网服务... 详细信息

为了解决当前物联网应用系统中存在的资源异构性和海量性问题,基于本体描述模型讨论物联网服务和资源的语义化描述方法,并在服务和资源之间建立相应的映射关系,最终形成一种面向物联网服务的资源统一表示模型。该模型为实现物联网服务和资源的最优化调度提供基础,同时能有效缓解当前物联网应用存在的垂直度较高问题。实验结果表明,该模型可以有效地对物联网中的原子服务和组合服务进行抽象表示,并能根据文中所提出的映射算法选择最佳的设备集以提高终端资源的利用率。

关键词：物联网资源表示模型服务语义表示 OWL-S 多终端聚合

Ti/Al比对GH984G合金长期时效过程中γ′沉淀相粗化行为及拉伸性能的影响

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金属学报 2014年第10期50卷 1260-1268页

作者：谭梅林王常帅郭永安郭建亭周兰章中国科学院金属研究所沈阳110016

研究了2种Ti/Al比对新型Ni-Fe-Cr基合金GH984G在长达上万小时高温时效过程中γ′淀相的粗化行为及其拉伸性能的影响规律.结果表明：随时效温度从700℃升高至800℃,球形γ′沉淀相的粗化速率明显增大.在700和750℃长期时效过程中,高Ti/A... 详细信息

研究了2种Ti/Al比对新型Ni-Fe-Cr基合金GH984G在长达上万小时高温时效过程中γ′淀相的粗化行为及其拉伸性能的影响规律.结果表明：随时效温度从700℃升高至800℃,球形γ′沉淀相的粗化速率明显增大.在700和750℃长期时效过程中,高Ti/Al比和低Ti/Al比合金γ′沉淀相的粗化行为均符合Lifshitz-Slyozof-Wagner（LSW）理论,受扩散过程控制,高Ti/Al比合金中γ′沉淀相的粗化速率较高.800℃长期时效过程中,2种Ti/Al比合金γ′沉淀相的粗化行为偏离LSW理论.此外,时效时间小于3×103h时,高Ti/Al比合金的γ′沉淀相长大较快,进一步延长时效时间,低Ti/Al比合金的γ′沉淀相长大速率较快.Ti/Al比对合金标准热处理态和700~800℃时效10480 h后合金的700℃拉伸性能无明显影响.通过选取合适的Ti/Al比,可以控制γ′沉淀相的粗化行为,增强合金组织稳定性.

关键词： Ni-Fe-Cr基合金长期时效 γ′沉淀相粗化行为拉伸性能

一种Ni-Fe-Cr基合金的凝固特征和偏析行为

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稀有金属材料与工程 2018年第12期47卷 3816-3823页

作者：王常帅苏海军郭永安郭建亭周兰章中国科学院金属研究所辽宁沈阳110016 西北工业大学凝固技术国家重点实验室陕西西安710072

采用定向凝固技术结合液淬法研究了一种Ni-Fe-Cr基合金平界面和枝晶生长条件下的凝固特征和溶质偏析行为。结果表明,合金的组成相为γ基体、MC型碳化物和γ′沉淀强化相,凝固顺序为L→L+γ→L+γ+MC→γ+γ′+MC。平界面生长条件下淬火... 详细信息

采用定向凝固技术结合液淬法研究了一种Ni-Fe-Cr基合金平界面和枝晶生长条件下的凝固特征和溶质偏析行为。结果表明,合金的组成相为γ基体、MC型碳化物和γ′沉淀强化相,凝固顺序为L→L+γ→L+γ+MC→γ+γ′+MC。平界面生长条件下淬火界面两侧溶质含量测定结果表明,Ti、Nb和Mo元素富集于液相,溶质分配系数小于1。Fe元素富集于固相,溶质分配系数大于1。Al和Cr元素在液固两相中浓度差别较小,溶质分配系数接近1。此外,固/液界面前沿存在溶质边界层,边界层内溶质原子通过扩散传输,边界层外主要借助流动传输。枝晶与平界面生长的溶质偏析行为基本一致,然而,枝晶生长时糊状区残余液相中溶质浓度与平界面生长时固/液界面前沿溶质浓度存在显著差别。枝晶生长条件下糊状区溶质偏析程度显著高于稳态生长区,固相反扩散和MC型碳化物的析出显著降低枝晶偏析程度。

关键词： Ni-Fe-Cr基合金凝固组织凝固路径溶质分配系数枝晶偏析