Efficient Traffic Engineering for 5G Core and Backhaul Networks

Gang Wang,Gang Feng,Shuang Qin,Ruihan Wen 한국통신학회 2017 Journal of communications and networks Vol.19 No.1

The next generation mobile networks (5G) should beefficient and elastic to accommodate numerous and diverse ser-vices. By explicitly assigning bandwidth to service flows, trafficengineering (TE) is effective to improve network efficiency andelasticity. Unfortunately, existing mobile network TE schemes aremostly focused on core network only, which is inadequate for effi-cient end-to-end traffic delivery in mobile networks. In this paper,we propose a TE framework that incorporates the data gateway(D-GW) selection and exploits the topology and traffic informa-tion of both core and backhaul networks for SDN-based 5G net-works. With ideal flow to D-GW association (IFDA) strategy, weformulate the TE problem as a multicommodity flow problem toachieve network load balancing. Considering the cooperation sig-nalling between D-GWs, we propose multiple BSs to one D-GWassociation (MBODA) and multiple flows to one D-GW associa-tion (MFODA) strategy, and formulate the corresponding TE prob-lems as mixed integer linear programs (MILPs) which are NP-hard. To efficiently solve the IFDA-TE problem, we design an im-proved version of fully polynomial time approximation scheme (i-FPTAS). Moreover, we propose a heuristic method and an LP re-laxation method that both use i-FPTAS to solve the MBODA-TEand MFODA-TE problems respectively. Numerical results showthat i-FPTAS achieves close-optimal solution with significantlylower computational complexity, compared with FPTAS, and theperformance of MFODA-TE is very close to that of the IFDA-TE,while there is a small performance degradation for MBODA-TE asthe cost of computational efficiency.

The Physical Layer Security Beamforming Method based on Large-scale Multi-antenna

Zhou Wen-gang,Li Jing,Guo Hui-ling 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.7

Network security with encryption and decryption technology to complete the application layer, but this technology will bring computing resources and a waste of energy, particularly in these two resources are limited wireless communication system for this problem, we use a large-scale multi-antenna technology, using beamforming algorithm in power and spectrum limited conditions, to maximize the mutual information system security, the simulation results demonstrate the ability to secure transmission algorithms can effectively improve the system.

An Improved Active Damping Method with Capacitor Current Feedback

Yi-Wen Geng,Ya-Wen Qi,Hai-Wei Liu,Fei Guo,Peng-Fei Zheng,Yong-Gang Li,Wen-Ming Dong 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

Proportional capacitor current feedback active damping (CCFAD) has a limited valid damping region in the discrete time domain as (0, fs/6). However, the resonance frequency (fr) of an LCL-type filter is usually designed to be less than half the sampling frequency (fs) with the symmetry regular sampling method. Therefore, (fs/6, fs/2) becomes an invalid damping region. This paper proposes an improved CCFAD method to extend the valid damping region from (0, fs/6) to (0, fs/2), which covers all of the possible resonance frequencies in the design procedure. The full-valid damping region is obtained and the stability margin of the system is analyzed in the discrete time domain with the Nyquist criterion. Results show that the system can operate stably with the proposed CCFAD method when the resonance frequency is in the region (0, fs/2). The performances at the steady and dynamic state are enhanced by the selected feedback coefficient H and controller gain Kp. Finally, the feasibility and effectiveness of the proposed CCFAD method are verified by simulation and experimental results.

Expression of Fatty Acid Synthase Negatively Correlates with PTEN and Predicts Peritoneal Dissemination of Human Gastric Cancer

Xiang, Hong-Gang,Hao, Jun,Zhang, Wen-Jie,Lu, Wen-Jie,Dong, Ping,Liu, Ying-Bin,Chen, Lei Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.16

Background: This study aimed to examine the clinical significance of fatty acid synthase (FASN) expression in gastric cancer (GC), and investigate any prognostic role. Materials and Methods: FASN expression was assessed in gastric cancers by immunohistochemistry using 60 paraffin-embedded tissue specimens, and clinical data were collected by retrospective chart review. Moreover, FASN mRNA expression in 15 fresh resected specimens was evaluated by the reverse transcription-polymerase chain reaction (RT-PCR). Immunohistochemical staining of PTEN was performed to assess the correlation of PTEN with FASN in gastric cancer. Results: Increased expression of FASN was noted in gastric cancers. The frequency of FASN gene amplification was also significantly higher in gastric cancer than in adjacent normal tissue. FASN expression in human gastric cancer tissues was significantly correlated with patient TNM stage and peritoneal dissemination (p<0.05). Moreover, higher FASN expression significantly correlated with shorter overall survival (p<0.05). Here, upregulation of FASN negatively correlated with PTEN expression in gastric cancer. Conclusions: These findings indicate that FASN expression is upregulated in gastric cancer, and increased FASN may be critical to th peritoneal metastasis and survival. Our results suggest that FASN upregulation and PTEN downregualtion may be involved in peritoneal dissemination for gastric cancer progression.

An Improved Active Damping Method with Capacitor Current Feedback

Geng, Yi-Wen,Qi, Ya-Wen,Liu, Hai-Wei,Guo, Fei,Zheng, Peng-Fei,Li, Yong-Gang,Dong, Wen-Ming The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

Proportional capacitor current feedback active damping (CCFAD) has a limited valid damping region in the discrete time domain as (0, $f_s/6$. However, the resonance frequency ($f_r$) of an LCL-type filter is usually designed to be less than half the sampling frequency ($f_s$) with the symmetry regular sampling method. Therefore, ($f_s/6$, $f_s/2$) becomes an invalid damping region. This paper proposes an improved CCFAD method to extend the valid damping region from (0, $f_s/6$ to (0, $f_s/2$), which covers all of the possible resonance frequencies in the design procedure. The full-valid damping region is obtained and the stability margin of the system is analyzed in the discrete time domain with the Nyquist criterion. Results show that the system can operate stably with the proposed CCFAD method when the resonance frequency is in the region (0, $f_s/2$). The performances at the steady and dynamic state are enhanced by the selected feedback coefficient H and controller gain $K_p$. Finally, the feasibility and effectiveness of the proposed CCFAD method are verified by simulation and experimental results.

Improving Cellulase Production in Trichoderma koningii Through RNA Interference on ace1 Gene Expression

( Wang Shao Wen ),( Miao Xing ),( Gang Liu ),( Shao Wen Yu ),( Juan Wang ),( Sheng Li Tian ) 한국미생물 · 생명공학회 2012 Journal of microbiology and biotechnology Vol.22 No.8

Ribonucleic acid interference (RNAi) inhibits the expression of target genes in a sequence-specific manner, and shows potential for gene knockdown in filamentous fungi, in which the locus-specific gene knockout occurs in low frequency. In this study, the function of the repressor of cellulase expression I (ACEI) was verified in Trichoderma koningii (T. koningii) YC01 through RNAi, and ace1-silenced strains with improved cellulase productivity were obtained. An expression cassette that transcribed the interfering double-stranded RNA (dsRNA) of ace1 was constructed and transformed into T. koningii, and the transformants, in which the expression of ace1 was successfully silenced, were selected. As a result of the ace1 gene silencing, the expression levels of the main cellulase and xylanase genes were elevated, and the enhanced production of total proteins, cellulase, and xylanase was observed in the cultivation. In addition, the downregulation of ace1 resulted in an increasing expression of xyr1, but no clear variation in the expression of cre1, which suggested that ACEI acted as a repressor of the xyr1 transcription, but was not involved in the regulation of the cre1 expression. The results of this work indicate that ace1 is a valid target gene for enhancing enzyme production in T. koningii, and RNAi is an appropriate tool for improving the properties of industrial fungi.

Online Monitoring System of Fish Behavior

Gang Xiao,Wen Zhang,Yong-Liang Zhang,Jiu-Jun Chen,Shan-Shan Huang,Lu-Ming Zhu 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10

In order to overcome the defect of physic-chemical monitoring system and enhance the intelligence of biological monitoring technology, an online monitoring system of fish behavior is proposed in this paper. The main contributions of this system are as follows: 1) adaptive background updating algorithm (ABU); 2) automatic camshift tracking algorithm (ACT) with twice searching; 3) particle filter tracking (PFT) algorithm; 4) persistent turning walker (PTW) model; 5) artificial immune algorithm (AIA). This online system is used to monitor and analyse the fish behavior continuously, establish a normal behavior model and detect the anormal behavior. Experimental results show that the system is running stably and has achieved well effect in the simulation environment.

Effects of Nutritional and Environmental Conditions on Planktonic Growth and Biofilm Formation of Citrobacter werkmanii BF-6

( Gang Zhou ),( Long Jie Li ),( Qing Shan Shi ),( You Sheng Ouyang ),( Yi Ben Chen ),( Wen Feng Hu ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.12

Citrobacter sp. is a cause of significant opportunistic nosocomial infection and is frequently found in human and animal feces, soil, and sewage water, and even in industrial waste or putrefaction. Biofilm formation is an important virulence trait of Citrobacter sp. pathogens but the process and characteristics of this formation are unclear. Therefore, we employed in vitro assays to study the nutritional and environmental parameters that might influence biofilm formation of C. werkmanii BF-6 using 96-well microtiter plates. In addition, we detected the relative transcript levels of biofilm formation genes by RT-PCR. Our results indicated that the capacity of C. werkmanii BF-6 to form biofilms was affected by culture temperature, media, time, pH, and the osmotic agents glucose, sucrose, NaCl, and KCl. Confocal laser scanning microscopy results illustrated that the structure of biofilms and extracellular polysaccharide was influenced by 100 mM NaCl or 100 mM KCl. In addition, nine biofilm formation genes (bsmA, bssR, bssS, csgD, csgE, csgF, mrkA, mrkB, and mrkE) were found to contribute to planktonic and biofilm growth. Our data suggest that biofilm formation by C. werkmanii BF-6 is affected by nutritional and environmental factors, which could pave the way to the prevention and elimination of biofilm formation using proper strategies.

Protective association of Klotho rs495392 gene polymorphism against hepatic steatosis in non-alcoholic fatty liver disease patients

Wen-Yue Liu,Xiaofang Zhang,Gang Li,Liang-Jie Tang,Pei-Wu Zhu,Rafael S. Rios,Kenneth I. Zheng,Hong-Lei Ma,Xiao-Dong Wang,Qiuwei Pan,Robert J. de Knegt,Luca Valenti,Mohsen Ghanbari,Ming-Hua Zheng 대한간학회 2022 Clinical and Molecular Hepatology(대한간학회지) Vol.28 No.2

Background/Aims: Non-alcoholic fatty liver disease (NAFLD) is closely associated with metabolic dysfunction. Among the multiple factors, genetic variation acts as important modifiers. Klotho, an enzyme encoded by the klotho (KL) gene in human, has been implicated in the pathogenesis of metabolic dysfunctions. However, the impact of variants in KL on NAFLD risk remains poorly understood. The aim of this study was to investigate the impact of KL rs495392 C>A polymorphism on the histological severity of NAFLD. Methods: We evaluated the impact of the KL rs495392 polymorphism on liver histology in 531 Chinese with NAFLD and replicated that in the population-based Rotterdam Study cohort. The interactions between the rs495392, vitamin D, and patatin-like phospholipase domain containing 3 (PNPLA3) rs738409 polymorphism were also analyzed. Results: Carriage of the rs495392 A allele had a protective effect on steatosis severity (odds ratio [OR], 0.61; 95% confidence interval [CI], 0.42–0.89; P=0.010) in Chinese patients. After adjustment for potential confounders, the A allele remained significant with a protective effect (OR, 0.66; 95% CI, 0.45–0.98; P=0.040). The effect on hepatic steatosis was confirmed in the Rotterdam Study cohort. Additional analysis showed the association between serum vitamin D levels and NAFLD specifically in rs495392 A allele carriers, but not in non-carriers. Moreover, we found that the rs495392 A allele attenuated the detrimental impact of PNPLA3 rs738409 G allele on the risk of severe hepatic steatosis. Conclusions: The KL rs495392 polymorphism has a protective effect against hepatic steatosis in patients with NAFLD.

Structural analysis and optimization of large cooling tower subjected to wind loads based on the iteration of pressure

Gang Li,Wen-bin Cao 국제구조공학회 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.46 No.5

The wind load is always the dominant load of cooling tower due to its large size, complex geometry and thin-wall structure. At present, when computing the wind-induced response of the large-scale cooling tower, the wind pressure distribution is obtained based on code regulations, wind tunnel test or computational fluid dynamic (CFD) analysis, and then is imposed on the tower structure. However, such method fails to consider the change of the wind load with the deformation of cooling tower, which may result in error of the wind load. In this paper, the analysis of the large cooling tower based on the iterative method for wind pressure is studied, in which the advantages of CFD and finite element method (FEM) are combined in order to improve the accuracy. The comparative study of the results obtained from the code regulations and iterative method is conducted. The results show that with the increase of the mean wind speed, the difference between the methods becomes bigger. On the other hand, based on the design of experiment (DOE), an approximate model is built for the optimal design of the large-scale cooling tower by a two-level optimization strategy, which makes use of code-based design method and the proposed iterative method. The results of the numerical example demonstrate the feasibility and efficiency of the proposed method.