Plasma-catalytic decomposition of ethyl acetate over LaMO3 (M = Mn, Fe, and Co) perovskite catalysts

Yuxiang Cai,Xinbo Zhu,Wenshuo Hu,Chenghang Zheng,Yangyang Hu,Menghan Chen,Xiang Gao 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.70 No.-

Plasma-catalytic decomposition of low concentration ethyl acetate with LaMO3 (M = Co, Mn and Fe)perovskite catalyst was investigated in a coaxial dielectric barrier discharge (DBD) reactor. Thecombination of perovskite catalyst and plasma enhanced ethyl acetate decomposition, and the activitysequence was LaCoO3> LaMnO3> LaFeO3. Characterizations results indicated that the activation ofsurface oxygen species and amount of oxygen vacancies contributed to ethyl acetate decompositionremarkably. FT-IR analysis demonstrated that the employment of LaCoO3 catalyst also reduced theamount of unwanted by-products. Based on these results, reaction mechanism of ethyl acetate plasmacatalyticdecomposition process was proposed.

A Mechanism for Configurable Network Service Chaining and Its Implementation

( Gang Xiong ),( Yuxiang Hu ),( Julong Lan ),( Guozhen Cheng ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.8

Recently Service Function Chaining (SFC) is promising to innovate the network service mode in modern networks. However, a feasible implementation of SFC is still difficult due to the need to achieve functional equivalence with traditional modes without sacrificing performance or increasing network complexity. In this paper, we present a configurable network service chaining (CNSC) mechanism to provide services for network traffics in a flexible and optimal way. Firstly, we formulate the problem of network service chaining and design an effective service chain construction framework based on integrating software-defined networking (SDN) with network functions virtualization (NFV). Then, we model the service path computation problem as an integer liner optimization problem and propose an algorithm named SPCM to cooperatively combine service function instances with a network utility maximum policy. In the procedure of SPCM, we achieve the service node mapping by defining a service capacity matrix for substrate nodes, and work out the optimal link mapping policies with segment routing. Finally, the simulation results indicate that the average request acceptance ratio and resources utilization ratio can reach above 85% and 75% by our SPCM algorithm, respectively. Upon the prototype system, it is demonstrated that CNSC outperforms other approaches and can provide flexible and scalable network services.

Hopf Bifurcation Study of Inductively Coupled Power Transfer Systems Based on SS-type Compensation

Chenyang Xia,Ying Yang,Yuxiang Peng,Aiguo Patrick Hu 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.3

In order to analyze the nonlinear phenomena of the bifurcation and chaos caused by the switching of nonlinear switching devices in inductively coupled power transfer (ICPT) systems, a Jacobian matrix model, based on discrete mapping numerical modeling, is established to judge the system stability of the periodic closed orbit and to study the nonlinear behavior of Hopf bifurcation in a system under full resonance. The general flow of the parameter design, based on the stability principle for ICPT systems, is proposed to avoid the chaos and bifurcation phenomena caused by unreasonable parameter selection. Firstly, based on the state equation of SS-type compensation, a three-dimensional bifurcation diagram with the coupling coefficient as the bifurcation parameter is established with a numerical simulation to observe the nonlinear phenomena in the system. Then Filippov’s method based on a Jacobian matrix model is adopted to deduce the boundary of stable operation and to judge the type of the bifurcation in the system. Then the general flow of the parameter design based on the stability principle for ICPT systems is proposed through the above analysis to realize stable operation under the conditions of weak coupling. Finally, an experimental platform is built to confirm the correctness of the numerical simulation and modeling.

Novel multiple-acidic ionic liquids: Green and efficient catalysts for the synthesis of bis-indolylmethanes under solvent-free conditions

Anguo Ying,Zhifeng Li,Yuxiang Ni,Songlin Xu,Hailiang Hou,Huanan Hu 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.24 No.-

Four novel multiple-acidic ionic liquids based on triethanolamine (TEA) were prepared and used as efficient catalysts to synthesize bis-indolylmethanes at room temperature without any organic solvent. [TEOA][HSO4] showed the best catalytic performance. The optimal amount of catalyst was 10 mol%. Various aldehydes/ketones reacted with indole/substituted indole smoothly and afforded to corresponding products in 70–99% yields within minutes. Additionally, the ionic liquid could be reused up to five times with only a slight decrease in catalytic activity. Finally, a possible reaction mechanism was given. Techniques of acidity test and NMR were introduced to verify the proposed mechanism.

DSL: Dynamic and Self-Learning Schedule Method of Multiple Controllers in SDN

Junfei Li,Jiangxing Wu,Yuxiang Hu,Kan Li 한국전자통신연구원 2017 ETRI Journal Vol.39 No.3

For the reliability of controllers in a software defined network (SDN), a dynamic and self-learning schedule method (DSL) is proposed. This method is original and easy to deploy, and optimizes the combination of multiple controllers. First, we summarize multiple controllers’ combinations and schedule problems in an SDN and analyze its reliability. Then, we introduce the architecture of the schedule method and evaluate multi-controller reliability, the DSL method, and its optimized solution. By continually and statistically learning the information about controller reliability, this method treats it as a metric to schedule controllers. Finally, we compare and test the method using a given testing scenario based on an SDN network simulator. The experiment results show that the DSL method can significantly improve the total reliability of an SDN compared with a random schedule, and the proposed optimization algorithm has higher efficiency than an exhaustive search.

An Optimized Deployment Mechanism for Virtual Middleboxes in NFV- and SDN-Enabling Network

( Gang Xiong ),( Penghao Sun ),( Yuxiang Hu ),( Julong Lan ),( Kan Li ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.8

Network Function Virtualization (NFV) and Software Defined Networking (SDN) are recently considered as very promising drivers of the evolution of existing middlebox services, which play intrinsic and fundamental roles in today`s networks. To address the virtual service deployment issues that caused by introducing NFV or SDN to networks, this paper proposes an optimal solution by combining quantum genetic algorithm with cooperative game theory. Specifically, we first state the concrete content of the service deployment problem and describe the system framework based on the architecture of SDN. Second, for the service location placement sub-problem, an integer linear programming model is built, which aims at minimizing the network transport delay by selecting suitable service locations, and then a heuristic solution is designed based on the improved quantum genetic algorithm. Third, for the service amount placement sub-problem, we apply the rigorous cooperative game-theoretic approach to build the mathematical model, and implement a distributed algorithm corresponding to Nash bargaining solution. Finally, experimental results show that our proposed method can calculate automatically the optimized placement locations, which reduces 30% of the average traffic delay compared to that of the random placement scheme. Meanwhile, the service amount placement approach can achieve the performance that the average metric values of satisfaction degree and fairness index reach above 90%. And evaluation results demonstrate that our proposed mechanism has a comprehensive advantage for network application.

Central Control over Distributed Service Function Path

( Dan Li ),( Julong Lan ),( Yuxiang Hu ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.2

Service Function Chaining (SFC) supports services through linking an ordered list of functions. There may be multiple instances of the same function, which provides a challenge to select available instances for all the functions in an SFC and generate a specific Service Function Path (SFP). Aiming to solve the problem of SFP selection, we propose an architecture consisting of distributed SFP algorithm and central control mechanism. Nodes generate distributed routings based on the first function and destination node in each service request. Controller supervises all of the distributed routing tables and modifies paths as required. The architecture is scalable, robust and quickly reacts to failures because of distributed routings. Besides, it enables centralized and direct control of the forwarding behavior with the help of central control mechanism. Simulation results show that distributed routing tables can generate efficient SFP and the average cost is acceptable. Compared with other algorithms, our design has a good performance on average cost of paths and load balancing, and the response delay to service requests is much lower.

Separating VNF and Network Control for Hardware-Acceleration of SDN/NFV Architecture

Tong Duan,Julong Lan,Yuxiang Hu,Penghao Sun 한국전자통신연구원 2017 ETRI Journal Vol.39 No.4

A hardware-acceleration architecture that separates virtual network functions (VNFs) and network control (called HSN) is proposed to solve the mismatch between the simple flow steering requirements and strong packet processing abilities of software-defined networking (SDN) forwarding elements (FEs) in SDN/network function virtualization (NFV) architecture, while improving the efficiency of NFV infrastructure and the performance of network-intensive functions. HSN makes full use of FEs and accelerates VNFs through two mechanisms: (1) separation of traffic steering and packet processing in the FEs; (2) separation of SDN and NFV control in the FEs. Our HSN prototype, built on NetFPGA-10G, demonstrates that the processing performance can be greatly improved with only a small modification of the traditional SDN/NFV architecture.

Hopf Bifurcation Study of Inductively Coupled Power Transfer Systems Based on SS-type Compensation

Xia, Chenyang,Yang, Ying,Peng, Yuxiang,Hu, Aiguo Patrick The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.3

In order to analyze the nonlinear phenomena of the bifurcation and chaos caused by the switching of nonlinear switching devices in inductively coupled power transfer (ICPT) systems, a Jacobian matrix model, based on discrete mapping numerical modeling, is established to judge the system stability of the periodic closed orbit and to study the nonlinear behavior of Hopf bifurcation in a system under full resonance. The general flow of the parameter design, based on the stability principle for ICPT systems, is proposed to avoid the chaos and bifurcation phenomena caused by unreasonable parameter selection. Firstly, based on the state equation of SS-type compensation, a three-dimensional bifurcation diagram with the coupling coefficient as the bifurcation parameter is established with a numerical simulation to observe the nonlinear phenomena in the system. Then Filippov's method based on a Jacobian matrix model is adopted to deduce the boundary of stable operation and to judge the type of the bifurcation in the system. Then the general flow of the parameter design based on the stability principle for ICPT systems is proposed through the above analysis to realize stable operation under the conditions of weak coupling. Finally, an experimental platform is built to confirm the correctness of the numerical simulation and modeling.

Microsatellite Markers Linked to Quantitative Trait Loci Affecting Fatness in Divergently Selected Chicken Lines for Abdominal Fat

Zhang, Hui,Wang, Shouzhi,Li, Hui,Yu, Xijiang,Li, Ning,Zhang, Qin,Liu, Xiaofeng,Wang, Qigui,Hu, Xiaoxiang,Wang, Yuxiang,Tang, Zhiquan Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.10

Abdominal fat characters are complex and economically important in the poultry industry. Their selection may benefit from the implementation of marker-assisted selection (MAS). The objective of this study was to identify the markers linked to QTL responsible for fatness traits. The Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF) were used in the study. A total of 596 individuals from the divergent tails from the 6th to the 10th generations were genotyped at 23 microsatellite markers on chromosome 1. The differences of allele frequencies of all marker alleles between the divergent tails across the five generations were recorded. The allele frequencies of five markers, including LEI0209, LEI0146, MCW0036, ADL328 and MCW0115, had significant differences between the two tails in all five generations. The resulting p-values using Fisher's exact test on eleven markers, containing MCW248, MCW0010, MCW0106, LEI0252, LEI0068, MCW0018, MCW0061, LEI0088, MCW200, MCW283 and ROS0025, had a decreasing tendency from the 6th to the 10th generation. Statistical analysis showed that polymorphisms of the eight markers, including LEI0209, LEI0146, ROS0025, MCW0115, MCW0010, MCW0036, MCW283, ADL328, were significantly (p<0.0011) or suggestively (p<0.05) associated with abdominal fat content (AFW and AFP) across generations. It is concluded that the eight markers could be associated with the QTL affecting the deposition of abdominal fat in broiler chickens.