Traffic Engineering and Manageability for Multicast Traffic in Hybrid SDN

( Cheng Ren ),( Sheng Wang ),( Jing Ren ),( Xiong Wang ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.6

Multicast communication can effectively reduce network resources consumption in contrast with unicast. With the advent of SDN, current researches on multicast traffic are mainly conducted in the SDN scenario, thus to mitigate the problems of IP multicast such as the unavoidable difficulty in traffic engineering and high security risk. However, migration to SDN cannot be achieved in one step, hybrid SDN emerges as a transitional networking form for ISP network. In hybrid SDN, for acquiring similar TE and security performance as in SDN multicast, we redirect every multicast traffic to an appropriate SDN node before reaching the destinations of the multicast group, thus to build up a core-based multicast tree substantially which is first introduced in CBT. Based on the core SDN node, it is possible to realize dynamic control over the routing paths to benefit traffic engineering (TE), while multicast traffic manageability can also be obtained, e.g., access control and middlebox-supported network services. On top of that, multiple core-based multicast trees are constructed for each multicast group by fully taking advantage of the routing flexibility of SDN nodes, in order to further enhance the TE performance. The multicast routing and splitting (MRS) algorithm is proposed whereby we jointly and efficiently determine an appropriate core SDN node for each group, as well as optimizing the traffic splitting fractions for the corresponding multiple core-based trees to minimize the maximum link utilization. We conduct simulations with different SDN deployment rate in real network topologies. The results indicate that, when 40% of the SDN switches are deployed in HSDN as well as calculating 2 trees for each group, HSDN multicast adopting MRS algorithm can obtain a comparable TE performance to SDN multicast.

Simulation and Investigation of Humidity Sensor based on Fiber Grating Fabry-Perot

Xiong Yanling,Liang Huan,Ren Naikui,Han Junsheng,Wu Mingze 보안공학연구지원센터 2015 International Journal of Hybrid Information Techno Vol.8 No.6

In this article we have discussed the relative humidity sensor based on fiber grating Fabry-Perot (FBG-FP) coated with polyimide (PI) as a moisture sensitive film in theory. The moisture expansion coefficient of PI film as moisture strain on the FBG-FP sensor, which will result the change of the fiber core effective refractive index, the length of the F-P cavity and the period and effective refractive index of FBG. For that reason, the interference fringes of the reflection spectrum will be changed also. The shift of peak wavelength of the spectrum is traced by the simulation of Matlab. We discuss three situations: the coating on the FBG, FP cavity and the both, and regardless of the temperature changes, the simulation results show that the RH sensitivity can reach to 3.77pm/%RH, 2.12 pm/%RH, 4.05 pm/%RH, respectively.

Study on FBG Wavelength Demodulation System with the Continuous Dynamic Scanning of Tunable DFB Laser

Xiong Yanling,Li Qiaoyi,Yang Wenlong,Yu Shengzuo,Ren Naikui,Liang Huan 보안공학연구지원센터(IJSIP) 2014 International Journal of Signal Processing, Image Vol.7 No.3

Age-dependent Changes of Differential Gene Expression Profile in Backfat Tissue between Hybrids and Parents in Pigs

Ren, ZH.Q.,Xiong, Yuanzhu,Deng, CH.Y.,Zuo, B.,Liu, Y.G.,Lei, M.G. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.5

Large White, an introduced European pig breed, and Meishan, a Chinese indigenous pig breed, were hybridized directly and reciprocally and a total of 260 pigs, including purebreds, Large White and Meishan, and their hybrids, White${\times}$Meishan (LM) and Meishan${\times}$Large White (ML) pigs, were bred in our laboratory. The mRNA differential display PCR (DD-PCR) was used to detect the age-dependent changes of differential gene expression in backfat tissue between hybrids and parents. Some measures were taken to reduce the false positives in our experiment. Among the total of 2,686 bands obtained, 1,952 bands (about 72.67%) were reproducible and eight patterns (fifteen kinds) of gene expression were observed. The percentage of differentially expressed genes between hybrids and parents is 56.86% at the age of four months and 57.71% at the age of six months. This indicated that the differences of gene expression between hybrids and their parents were very obvious. U-test was used to compare the patterns of gene expression between the age of four and six months, and results showed that bands occurring in only one hybrid and bands displayed in one hybrid and one parent were significantly different at p<0.05, and bands visualized in only two hybrids were significantly different at p<0.01. These indicated that differential gene expression between hybrids and parents changed at different ages.

Experimental investigation on the seismic behavior of reinforced concrete column-steel beam subassemblies

Liquan Xiong,Jinjie Men,Ruyue Ren,Mengke Lei 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.28 No.4

The composite reinforced concrete and steel (RCS) structural systems have larger structural lateral stiffness, higher inherent structural damping, and faster construction speed than either traditional reinforcement concrete or steel structures. In this paper, four RCS subassemblies with or without the RC slab designed following a strong column-weak beam philosophy were constructed and tested under reversed-cyclic loading. Parameters including the width of slab and composite effect of the RC slab and beam were explored. The test results showed that all specimens performed in a ductile manner with plastic hinges formed in the beam ends near the column faces. The seismic responses of composite connections are influenced significantly by different width of slabs. Compared with that of the steel beam without the RC slab, it was found that the load carrying capacity of composite connections with the RC slab increased by 30% on average, and strength degradation, energy dissipation also had better performance, while the ductility of that were almost the same. Furthermore, the contribution of connection deformation to the overall specimen displacement was analyzed and compared. It decreased approximately 10% due to the coupling effect in the columns and beams with the RC slab. Based on the test result, some suggestions are presented for the design of composite RCS joints.

Self-assembled magnetic lamellar hydroxyapatite as an efficient nanovector for gene delivery

Guangyao Xiong,Yizao Wan,Guifu Zuo,Kaijing Ren,Honglin Luo 한국물리학회 2015 Current Applied Physics Vol.15 No.7

Magnetic lamellar hydroxyapatite (ML-HA) nanoparticles were synthesized by a template-assisted selfassembly process. The as-prepared ML-HA nanoparticles self-assembled under different conditions were characterized by XRD, TEM, cytotoxicity assessment, and DNA-loading and transfection efficiency measurements. We found that the structure and morphology of ML-HA were controlled by self-assembly conditions. The ML-HA synthesized in this work exhibited good biocompatibility. The DNA-loading capacity and z-potential of ML-HA were much lower in comparison to bare lamellar HA (L-HA) without magnetic nanoparticles. Despite that, the ML-HA with good lamellar structure showed 47% higher transfection efficiency than L-HA. Results suggested that the ordered lamellar structure is a key factor in controlling transfection efficiency and magnetization is an effective way of improving the transfection efficiency of lamellar HA. Mechanisms were proposed to interpret these experimental results. It is demonstrated that the ML-HA may be a promising gene vector to deliver DNA into the cells effectively and safely.

Determination of optimal conditions for ribonucleic acid production by Candida tropicalis no. 121

Huajing Ren,Hanjie Ying,Xiaochun Chen,Jiaming Cao,Lei Li,Jianxin Bai,Yong Chen,Jian Xiong 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.8

The experiments were based on multivariate statistical concepts, and response surface methodology (RSM)was applied to optimize the fermentation medium for the production of ribonucleic acid (RNA) by Candida tropicalis no. 121. The process involved the individual adjustment and optimization of various medium components at shake flask level. The two-level Plackett-Burman (PB) design was used to screen the medium components, which significantly influenced RNA production. Among seven variables, the concentrations of molasses, ZnSO_4, and H_3PO_4 were found to be the important factors that significantly affected RNA production (confidence levels above 95%). These factors were further optimized using a central composite design (CCD) and RSM. The optimum values for the critical components were as follows: molasses 47.21 g/L: ZnSO_4 0.048 g/L; H_3PO_4 1.19 g/L. Under optimal conditions, RNA production was 2.56 g/L, which was in excellent agreement with the predicted value (2.561 g/L), and led to a 2.1-fold increase compare with that using the original medium in RNA production.

Fiber-Optic Current Sensor Head Based on the Giant Magnetostrictive Materials

Naikui Ren,Yanling Xiong,Mingze Wu,Yuelan Lv,Lianjin Hong 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.6

A current sensing method based on giant magnetostrictive material (GMM) and fiber Bragg grating (FBG) was proposed, which not only combines the advantages of FBG such as wavelength encoding, compatibility with fiber and distributed measurement system realization, but also the advantages of GMM as large flexible coefficient, high electromechanical coupling coefficient and short response time. The minimal residual method was put forward to effectively identify the Jiles-Atherton model parameters of ferro-magnetic material. The parameters of the giant magnetostrictive ( Terfenol-D bar ) and the Jiles-Atherton model was established and optimized by using the Mathematica software. Then the optical fiber current test system with ferromagnetic loop was set up to investigate the current sensing properties of the sensor. The relationship between current excitation and GMM-FBG reflected wavelength was obtained, which provides basic support for further current sensing experiment research.

Isolation, Expression Pattern, Polymorphism and Association Analysis of Porcine TIAF1 Gene

Wang, Y.,Xiong, Y.Z.,Ren, Z.Q.,Zuo, B.,Lei, M.G.,Deng, C.Y. Asian Australasian Association of Animal Productio 2009 Animal Bioscience Vol.22 No.3

TIAF1 is a TGF-${\beta}$1-induced anti-apoptotic factor that plays a critical role in blocking TNF (tumor necrosis factor) cytotoxicity in mouse fibroblasts and participates in TGF-${\beta}$-mediated growth regulation. In this study, we obtained the full-length cDNA sequence of the porcine TIAF1 gene. Real-time PCR further revealed that the TIAF1 gene was expressed at the highest level in liver and kidney with prominent expressions detected in uterus, and lower levels detected in heart, spleen, lung, stomach, small intestine, skeletal muscle and fat of Large White pigs. Sequence analysis indicated that a 6 base-pair deletion mutation existed in the exon of the TIAF1 gene between Meishan and Large White pigs. This mutation induced deletion of Gln and Val amino acids. PCR-RFLP was used to detect the polymorphism in 394 pigs of a "Large White${\times}$Meishan" $F_{2}$ resource population and four purebred pig populations. The frequencies of the A allele (with a 6 bp deletion) were dominant in Chinese Meishan and Bamei pigs, and the frequencies of the B allele (no 6 bp deletion) were dominant in Large White and Landrace pigs. Association analyses revealed that the deletion mutation had highly significant associations (p<0.01) with meat marbling score of the thorax-waist longissimus dorsi (LD) muscle (MM1) and intramuscular fat percentage (IMF), and significant associations (p<0.05) with carcass length (CL). The results presented here supply evidence that the 6 bp deletion mutation in the TIAF1 gene affects porcine meat quality and provides useful information for further porcine breeding.

Routing Optimization For Cloud Services in SDN-based Internet of Things With TCAM Capacity Constraint

Shizhong Xu,Xiong Wang,Guangxu Yang,Jing Ren,Sheng Wang 한국통신학회 2020 Journal of communications and networks Vol.22 No.2

Distributed in-network cloud architecture is a promisingsolution to efficiently host next generation internet-of-things (IoT)services. With the rapid increase of IoT devices and applications,the backhaul or backbone networks, which transmit IoT trafficto various in-network clouds, will experience a predicted explosionin the volume of carried traffic. To guarantee the QoS of IoTcloud services and improve the network performance, it is crucialfor network operator to implement efficient routing optimizationstrategies for IoT traffic. As a promising networking paradigm,software-defined networking (SDN) has flexible and programmablecontrol capability for fine-grained flows. The emergence of SDNpaves a way for implementing high-performance routing optimizationin networks. In SDN networks, the routing strategies are realizedthrough flow rules, which are usually stored in TCAM withvery limited capacity. However, the number of IoT flows are enormous. Thus, in this paper, we address the routing optimizationproblem in SDN-based IoT with TCAM capacity constraint. Wefirst formulate the problem as a mixed integer linear programmingproblem and prove the problem is NP-hard. Then to solve theproblem efficiently, we propose several approximate algorithms,which solve the problem in two stages. In the first stage, the algorithmscalculate the routing strategies for flows without consideringthe TCAM capacity constraint. To meet the TCAM capacityconstraint, the algorithms using different strategies to adjust thepaths of some flows in the second stage. Extensive simulations areconducted on both real ISP and synthetic topologies to evaluate theperformance of the algorithms. The simulation results verify thatthe algorithms can achieve promising load balancing performancein SDN-based IoT, where the capacity of TCAM in SDN switches isvery limited.