期刊：
IEEE INTERNET OF THINGS JOURNAL,2020年7(7):5792-5805 ISSN：2327-4662
通讯作者：
Zhang, SG
作者机构：
[Zhang, SG; Huang, Mingfeng; Zhang, Shigeng; Liu, Anfeng] Cent South Univ, Sch Comp Sci & Engn, Changsha 410083, Peoples R China.;[Liu, Wei] Hunan Univ Chinese Med, Sch Informat, Changsha 410208, Peoples R China.;[Wang, Tian] Huaqiao Univ, Coll Comp Sci & Technol, Xiamen 361021, Peoples R China.;[Zhang, Shigeng] Nanjing Univ, State Key Lab Novel Software Technol, Nanjing 210093, Peoples R China.
通讯机构：
[Zhang, SG ] C;Cent South Univ, Sch Comp Sci & Engn, Changsha 410083, Peoples R China.
关键词：
Task analysis;Cloud computing;Servers;Computational modeling;Delays;Energy consumption;Internet of Things;Delay;energy consumption;Internet of Things (IoT);service orchestration;task offloading decision
摘要：
Billions of devices are connected to the Internet of Things (IoT). These devices generate a large volume of data, which poses an enormous burden on conventional networking infrastructures. As an effective computing model, edge computing is collaborative with cloud computing by moving part intensive computation and storage resources to edge devices, thus optimizing the network latency and energy consumption. Meanwhile, the software-defined networks (SDNs) technology is promising in improving the quality of service (QoS) for complex IoT-driven applications. However, building SDN-based computing platform faces great challenges, making it difficult for the current computing models to meet the low-latency, high-complexity, and high-reliability requirements of emerging applications. Therefore, a cloud-mobile edge computing (MEC) collaborative task offloading scheme with service orchestration (CTOSO) is proposed in this article. First, the CTOSO scheme models the computational consumption, communication consumption, and latency of task offloading and implements differentiated offloading decisions for tasks with different resource demand and delay sensitivity. What is more, the CTOSO scheme introduces orchestrating data as services (ODaS) mechanism based on the SDN technology. The collected metadata are orchestrated as high-quality services by MEC servers, which greatly reduces the network load caused by uploading resources to the cloud on the one hand, and on the other hand, the data processing is completed at the edge layer as much as possible, which achieves the load balancing and also reduces the risk of data leakage. The experimental results demonstrate that compared to the random decision-based task offloading scheme and the maximum cache-based task offloading scheme, the CTOSO scheme reduces delay by approximately 73.82%-74.34% and energy consumption by 10.71%-13.73%.
通讯机构：
[Zeng, ZW ] C;Cent South Univ, Sch Comp Sci & Engn, Changsha 410083, Hunan, Peoples R China.
关键词：
Buffer size;Delay;Energy consumption;Lifetime;Wireless video sensor networks
摘要：
Due to battery-powered wireless video sensor networks (WVSNs) takes on a high video data volume, it becomes a crucial issue to reduce energy consumption to maximize lifetime. At the same time, WVSNs are often applied to important situations for real-time and semi-real-time monitoring, thus ensuring the rapid transmission of these perceived data to sink is another critical issue. In static random-access memory (SRAM) communication buffer-based WVSN node, the radio is turned off during the data buffer-filling period as well as idle period. Because each radio transition contains the additional energy consumed by invalid packet header information and communication connection establishment, and the radio ON/OFF transition incurs extra circuit energy consumption. Therefore, from the perspective of saving energy, we need to reduce the ON/OFF transition frequency, which requires a large-sized buffer. However, the large size of SRAM buffer results in more energy consumption because SRAM energy consumption is proportional to the memory size. More importantly, the large ON/OFF transition frequency will lead to a large data transmission delay, which is harmful to applications. In this paper, an adaption resizing communication buffer (ARCB) scheme is proposed to maximize lifetime and reduce delay for WVSNs. In the ARCB scheme, the buffer size takes the minimum energy consumption optimization value in hotspot areas to maximize lifetime and takes a value smaller than the optimized value in non-hotspot areas to reduce delay. Although this consumes more energy for communication, since nodes in the non-hotspot areas have energy surpluses, it will not affect the lifetime. As a result, ARCB scheme can simultaneously increase the lifetime and reduce the delay in WVSNs. The effectiveness of the ARCB scheme is verified by theoretical analysis. The results show that the proposed ARCB scheme reduces the delay by 27.9%, and increases the effective utilization of energy by 24.1% under the condition that its lifetime is no less than previous schemes.
摘要：
Cyber-physical-social (CPS) systems integrate Big Data Collectors (BDCs), Service Organizers (SOs) and users to build a unified data-centric computing framework. In CPS systems, BDCs leverage a vast variety of sensing devices to collect cyber-physical-social data, and report these data to SOs to orchestrate various services provided to users, thus offering a great potential for solving complex network tasks that are far beyond the capabilities of existing networks. However, due to the lack of an economic model to describe such complex data interactions, their applications are limited. So, a game-based economic model is proposed in this paper to make smart price decisions in CPS systems. Specifically, it has the following innovations: (a) The economic model gives a dynamic game income matrix which can accurately describe the revenue changes of BDCs in the game, so as to help BDCs select appropriate game parameters and strategies, and make BDCs competitive in the game. (b) The economic model can help SOs to make optimized data purchase price and service selling price based on data collection cost and competitor price analysis, so that SOs can have a better Quality of Service (QoS) and users attraction, and maximize the profit. Experimental results demonstrate that the proposed model can help BDCs and SOs find the most suitable game strategy and price adjustment principle, which has great significance in applications.
作者机构：
[Kui, Xiaoyan; Teng, Haojun; Kui, XY] Cent South Univ, Sch Comp Sci & Engn, Changsha 410083, Hunan, Peoples R China.;[Liu, Wei] Hunan Univ Chinese Med, Sch Informat, Changsha 410208, Hunan, Peoples R China.;[Wang, Tian] Huaqiao Univ, Dept Comp Sci & Technol, Xiamen 361021, Fujian, Peoples R China.;[Zhang, Shaobo] Hunan Univ Sci & Technol, Sch Comp Sci & Engn, Xiangtan 411201, Peoples R China.;[Xiong, Neal N.] Northeastern State Univ, Dept Math & Comp Sci, Tahlequah, OK 74464 USA.
通讯机构：
[Kui, XY ] C;Cent South Univ, Sch Comp Sci & Engn, Changsha 410083, Hunan, Peoples R China.
关键词：
collaborative code dissemination;Urban computing;vehicle to everything;vehicles as code mules
摘要：
Urban computing creates novel solutions for smart city systems by integrating with ubiquitous sensing, cooperative communication, and data/code collection or dissemination technologies. In this paper, a collaborative code dissemination (CCD) approach with two-way vehicle to everything (V2X) paradigm is proposed by using vehicles act as code mules to disseminate code with fast and low cost style for urban Computing. The main innovation of the CCD-V2X scheme, which is different from the previous code dissemination method, is the use of three cooperative communication methods to speed up the dissemination of code. They are Roadside Smart Devices (RSDs) to vehicle (R2V), vehicle to vehicle (V2V) and R2V combined V2V (R2V-V2V) communications method. The corresponding three code dissemination schemes are proposed as follow: (1) The Code Dissemination with Roadside Smart Device Assisted (short as CDRSDA) scheme is proposed for vehicles to fast disseminate code in which the vehicles can receive code from RSDs that have get update code. (2) A Code Dissemination with V2V Transmission Assisted (short as CDVVA) scheme is proposed to improve the performance of code dissemination by enabling the transmission from code mules that have update code to the code mules that have no update code. (3) The R2V combined V2V (R2V-V2V) scheme is proposed which can further improve the performance by using both R2V and V2V communication method. The CCD scheme has been extensively experimentally verified by using real vehicle trajectory data. The experimental results show that: Compared with the Traditional Scheme, the CDRSDA scheme, CDVVA scheme, R2V-V2V scheme can be increased by up to 35.42%, 35.42%, 34.72%, respectively from the code diffusion coverage performance index, and from the speed performance indicators, the three schemes increased by at least 68.4%, 89.3% and 90.3%.
期刊：
International Journal of Circuits, Systems and Signal Processing,2018年12:215-219 ISSN：1998-4464
通讯作者：
Hu, Zhigang(zghu@csu.edu.cn)
作者机构：
[Hu, Zhigang; He, Feng; Zhou, Yuanyuan] Software College, Central South University, Changsha, Hunan, 410075, China;[Liu, Wei] School of Management and Information Engineering, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China
通讯机构：
Software College, Central South University, Changsha, Hunan, China
通讯机构：
[Zeng, JG ] H;Hunan Agr Univ, Hunan Key Lab Tradit Chinese Vet Med, Changsha 410128, Hunan, Peoples R China.;Hunan Agr Univ, Coll Hort & Landscape, Changsha 410128, Hunan, Peoples R China.;Hunan Agr Univ, Natl & Local Union Engn Res Ctr, Vet Herbal Med Resource & Initiat, Changsha 410128, Hunan, Peoples R China.
摘要：
Sanguinarine is currently widely used to replace antibiotic growth promoters in animal feeding and has demonstrated useful anticancer activity. Currently, the main source of sanguinarine is from an important medicinal plant, Macleaya cordata. To obtain a new source of sanguinarine production, we established hairy root cultures of M. cordata by co-cultivating leaf and stem explants with Agrobacterium rhizogenes. Except the co-cultivation medium, all growth media contained 200 mg/L timentin to eliminate A. rhizogenes. Through comparing the metabolic profiles and gene expression of hairy roots and wild-type roots sampled at five time points, we found that the sanguinarine and dihydrosanguinarine contents of hairy roots were far higher than those of wild-type roots, and we revealed the molecular mechanism that causes these metabolites to increase. Consequently, this study demonstrated that the hairy root system has further potential for bioengineering and sustainable production of sanguinarine on a commercial scale. To the best of our knowledge, this is the first efficient protocol reported for the establishment of hairy root cultures in M. cordata using A. rhizogenes.
