Distributed control system architecture for deep submergence rescue vehicles

Yushan Sun,Xiangrui Ran,Guocheng Zhang,Fanyu Wu,Chengrong Du 대한조선학회 2019 International Journal of Naval Architecture and Oc Vol.11 No.1

The control architectures of Chuan Suo (CS) deep submergence rescue vehicle are introduced. The hardware and software architectures are also discussed. The hardware part adopts a distributed control system composed of surface and underwater nodes. A computer is used as a surface control machine. Underwater equipment is based on a multi-board-embedded industrial computer with PC104 BUS, which contains IO, A/D, D/A, eight-channel serial, and power boards. The hardware and software parts complete data transmission through optical fibers. The software part involves an IPC of embedded Vxworks real-time operating system, upon which the operation of I/O, A/D, and D/A boards and serial ports is based on; this setup improves the real-time manipulation. The information flow is controlled by the software part, and the thrust distribution is introduced. A submergence vehicle heeling control method based on ballast water tank regulation is introduced to meet the special heeling requirements of the submergence rescue vehicle during docking. Finally, the feasibility and reliability of the entire system are verified by a pool test.

Distributed control system architecture for deep submergence rescue vehicles

Sun, Yushan,Ran, Xiangrui,Zhang, Guocheng,Wu, Fanyu,Du, Chengrong The Society of Naval Architects of Korea 2019 International Journal of Naval Architecture and Oc Vol.11 No.1

The control architectures of Chuan Suo (CS) deep submergence rescue vehicle are introduced. The hardware and software architectures are also discussed. The hardware part adopts a distributed control system composed of surface and underwater nodes. A computer is used as a surface control machine. Underwater equipment is based on a multi-board-embedded industrial computer with PC104 BUS, which contains IO, A/D, D/A, eight-channel serial, and power boards. The hardware and software parts complete data transmission through optical fibers. The software part involves an IPC of embedded Vxworks real-time operating system, upon which the operation of I/O, A/D, and D/A boards and serial ports is based on; this setup improves the real-time manipulation. The information flow is controlled by the software part, and the thrust distribution is introduced. A submergence vehicle heeling control method based on ballast water tank regulation is introduced to meet the special heeling requirements of the submergence rescue vehicle during docking. Finally, the feasibility and reliability of the entire system are verified by a pool test.

A Fast and Accurate Algorithm for Detecting Community Structure in Social Networks

Junheng Huang,Yushan Sun,Yang Liu,Bailing Wang 보안공학연구지원센터(IJUNESST) 2015 International Journal of u- and e- Service, Scienc Vol.8 No.1

Studies of community structure and evolution in large social networks require fast and accurate algorithms for community detection. Among the existing algorithms for community detection, the label propagation algorithm (LPA) and the Newman modularity Q algorithm (NMA) have been widely used and studied in the community detection in large social networks, since the LPA has the advantages of near-linear running time, easy implementation and without requiring parameters, and the NMA is a relatively fast algorithm and has a clear metrics to measure community structure. However, the LPA has the shortcomings that the result of the community detection is instable and has a low quality. At the same time, disadvantages of the NMA are that it bases its decisions on purely local information about individual communities and gets the local optimal solution. In this paper, combined with these two algorithms, we propose a new community detection algorithm (LP-NMA), which extends the above two algorithms (the LPA and the NMA is a special case of the new algorithm respectively). The new algorithm not only retains the advantages of these two algorithms, but also has improved the stability and quality of community detection. Experiments on real social networks have proved that this method is better than the original LPA and NMA.

Changes in microbial population and chemical composition of corn stover during field exposure and effects on silage fermentation and in vitro digestibility

Lin Sun,Zhijun Wang,Ge Gentu,Yushan Jia,Meiling Hou,Yimin Cai 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.6

Objective: To effectively use corn stover resources as animal feed, the changes in microbial population and chemical composition of corn stover during field exposure, and their silage fermentation and in vitro digestibility were studied. Methods: Corn cultivars (Jintian, Jinnuo, and Xianyu) stovers from 4 random sections of the field were harvested at the preliminary dough stage of maturity on September 2, 2015. The corn stover exposed in the field for 0, 7, 15, 30, 60, 90, and 180 d, and their silages at 60 d of ensiling were used for the analysis of microbial population, chemical composition, fermentation quality, and in vitro digestibility. Data were analyzed with a completely randomized 3×6 [corn stover cultivar (C)×exposure d (D)] factorial treatment design. Analysis of variance was performed using SAS ver. 9.0 software (SAS Institute Inc., Cary, NC, USA). Results: Aerobic bacteria were dominant population in fresh corn stover. After ensiling, the lactic acid bacteria (LAB) became the dominant bacteria, while other microbes decreased or dropped below the detection level. The crude protein (CP) and water-soluble carbohydrate (WSC) for fresh stover were 6.74% to 9.51% and 11.75% to 13.21% on a dry matter basis, respectively. After exposure, the CP and WSC contents decreased greatly. Fresh stover had a relatively low dry matter while high WSC content and LAB counts, producing silage of good quality, but the dry stover did not. Silage fermentation inhibited nutrient loss and improved the fermentation quality and in vitro digestibility. Conclusion: The results confirm that fresh corn stover has good ensiling characteristics and that it can produce silage of good quality.

Finite-time Controller Design for Four-wheel-steering of Electric Vehicle Driven by Four In-wheel Motors

Qing-Hua Meng,Zong-Yao Sun,Yushan Li 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.4

A smooth control method may do not obtain a desired convergence. On the other hand, a no-continuous method may cause a close-loop system to chatter. In order to avoid the aforementioned disadvantages, a non-smooth finite-time control method is proposed and applied on an active four-wheel-steering electric vehicle driven by four in-wheel motors to improve the safety and manoeuvrability in this paper. Based on an ideal electric vehicle steering tracking model, a non-smooth finite-time convergence controller is constructed for controlling the four wheels’ steering angles of an electric vehicle. The front wheel cornering stiffness, rear wheel cornering stiffness and external disturbance of a practical car are regarded as bounded uncertain parameters according to practical conditions. An A-class car model in the Carsim software is utilized to simulate the designed controller. The simulation results show that the controller based on finite-time convergence can track the ideal vehicle steering model better to obtain zero sideslip angle and expected yaw rate even when there exist perturbation of cornering stiffness and disturbance of lateral wind. It means the control system of the electric vehicle is robust with uncertainty. The simulation results also show that the non-smooth finite-time control method is better than the slide mode control method for the active four-wheel-steering system of the electric vehicle.

Stretchable Wire-Shaped Asymmetric Supercapacitors Based on Pristine and MnO₂ Coated Carbon Nanotube Fibers

Xu, Ping,Wei, Bingqing,Cao, Zeyuan,Zheng, Jie,Gong, Ke,Li, Faxue,Yu, Jianyong,Li, Qingwen,Lu, Weibang,Byun, Joon-Hyung,Kim, Byung-Sun,Yan, Yushan,Chou, Tsu-Wei American Chemical Society 2015 ACS NANO Vol.9 No.6

<P>While the emerging wire-shaped supercapacitors (WSS) have been demonstrated as promising energy storage devices to be implemented in smart textiles, challenges in achieving the combination of both high mechanical stretchability and excellent electrochemical performance still exist. Here, an asymmetric configuration is applied to the WSS, extending the potential window from 0.8 to 1.5 V, achieving tripled energy density and doubled power density compared to its asymmetric counterpart while accomplishing stretchability of up to 100% through the prestrainning-then-buckling approach. The stretchable asymmetric WSS constituted of MnO<SUB>2</SUB>/CNT hybrid fiber positive electrode, aerogel CNT fiber negative electrode and KOH-PVA electrolyte possesses a high specific capacitance of around 157.53 μF cm<SUP>–1</SUP> at 50 mV s<SUP>–1</SUP> and a high energy density varying from 17.26 to 46.59 nWh cm<SUP>–1</SUP> with the corresponding power density changing from 7.63 to 61.55 μW cm<SUP>–1</SUP>. Remarkably, a cyclic tensile strain of up to 100% exerts negligible effects on the electrochemical performance of the stretchable asymmetric WSS. Moreover, after 10 000 galvanostatic charge–discharge cycles, the specific capacitance retains over 99%, demonstrating a long cyclic stability.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2015/ancac3.2015.9.issue-6/acsnano.5b01244/production/images/medium/nn-2015-012442_0007.gif'></P>