A load-balancing mechanism for distributed SDN control plane using response time.

Software-Defined Networking (SDN) has become a popular paradigm for managing large-scale networks including cloud servers and data centers because of its advantages of centralized management and programmability. The issues of scalability and reliability that a single centralized controller suffers makes distributed controller architectures emerge. One key limitation of distributed controllers is the statically configured switch-controller mapping, easily causing uneven load distribution among controllers. Previous works have proposed load-balancing methods with switch migration to address this issue. However, the higher-load controller is always directly considered as the overloaded controller that need to shift its load to other controllers, even if it has no response time delay. The pursuit of absolute load-balancing effect can also result in frequent network delays and service interruptions. Additionally, if there are several overloaded controllers, just one controller with the maximum load can be addressed within a single load-balancing operation, reducing load-balancing efficiency. To address these problems, we propose SMCLBRT, a load-balancing strategy of multiple SDN controllers based on response time, considering the changing features of real-time response times versus controller loads. By selecting the appropriate response time threshold and dealing with multiple overloading controllers simultaneously, it can well solve load-balancing problem in SDN control plane with multiple overloaded controllers. Simulation experiments exhibit the effectiveness of our scheme.N/

An Efficient SDN load balancing scheme based on variance analysis for massive mobile users

In a traditional network, server load balancing is used to satisfy the demand for high data volumes. The technique requires large capital investment while offering poor scalability and flexibility, which difficultly supports highly dynamic workload demands from massive mobile users. To solve these problems, this paper analyses the principle of software-defined networking (SDN) and presents a new probabilistic method of load balancing based on variance analysis. The method can be used to dynamically manage traffic flows for supporting massive mobile users in SDN networks. The paper proposes a solution using the OpenFlow virtual switching technology instead of the traditional hardware switching technology. A SDN controller monitors data traffic of each port by means of variance analysis and provides a probability-based selection algorithm to redirect traffic dynamically with the OpenFlow technology. Compared with the existing load balancing methods which were designed to support traditional networks, this solution has lower cost, higher reliability, and greater scalability which satisfy the needs of mobile users.The work was supported by the National Natural Science Foundation of China (no. 61173188, no. 61572001, and no. 61502008), the Research Fund for the Doctoral Program of Higher Education (no. 20133401110004), the Educational Commission of Anhui Province, China (no. KJ2013A017), the Natural Science Foundation of Anhui Province (no. 1508085QF132), the Tender Project of the Co-Innovation Center for Information Supply & Assurance Technology of Anhui University (no. ADXXBZ2014-7), and the Doctoral Research Startup Funds Project of Anhui University

THE SOLUTION OF FRACTIONAL NONLINEAR GINZBURG-LANDAU EQUATION WITH WEAK INITIAL DATA

Abstract. In this paper, we study the solution of the fractional nonlinear Ginzburg-Landau(FNGL) equation with weak initial data in the weighted Lebesgue spaces. The existence of a solution to this equation is proved by the contraction-mapping principle

In vivo anti-inflammatory activity of Liquidambar formosana Hance infructescence extract

Purpose: To evaluate the anti-inflammatory activity of Liquidambar formosana  Hance infructescence (Liquidambaris fructus, ELF) in vivo, and clarify its underlying mechanisms. Methods: The in vivo anti-inflammatory activity of ELF was examined by xylene-induced ear swelling test in mice as well as carrageenan-induced paw edema method in rats. The levels of inflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-10) in serum were measured by enzyme-linked immunosorbent assay (ELISA), while the expressions of COX-2, iNOS and NF-κB p65 in paw tissue of rats were evaluated by western blot.Results: After ELF treatment, the levels of TNF-α (p < 0.001), IL-1β (p < 0.001) and IL-6 (p < 0.001) in serum decreased and the levels of anti-inflammatory cytokine IL-10 increased (p < 0.01). In addition, ELF treatment resulted in decrease of COX-2 (p < 0.01), iNOS (p < 0.01) and NF-κB p65 (p < 0.01) expressions in Wistar rats.Conclusion: The results reveal that ELF possesses significant anti-inflammatory effect in vivo. The anti-inflammatory activity is associated with the levels of TNF-α, IL-1β, IL-6 and IL-10 in serum. Furthermore, the suppression of NF-κB p65, iNOS and COX-2 is linked to its anti-inflammatory effect. These results provide a rationale for the use of Liquidambaris fructus in inflammatory disease in traditional medicine.Keywords: Anti-inflammatory activity, Liquidambaris fructus, Cytokines, Ear swelling test, Paw edem

A mutation in the interferon regulatory element of HBV may influence the response of interferon treatment in chronic hepatitis B patients

<p>Abstract</p> <p>Background</p> <p>A functional interferon regulatory element (IRE) has been found in the EnhI/X promoter region of hepatitis B virus (HBV) genome. The purpose of this study is to compare the gene order of responder and non-responder to interferon therapy in patients with chronic hepatitis B (CHB), so as to evaluate the relationship between IRE mutation and the response to interferon treatment for CHB patients.</p> <p>Results</p> <p>Synthetic therapeutic effect is divided into complete response (CR), partial response (PR) and non-response (NR). Among the 62 cases included in this study, 40 cases (64.5%) were in the response group (CR and PR) and 22 (35.5%) cases were in the NR group. Wild type sequence of HBV IRE TTTCACTTTC were found in 35 cases (56.5%), and five different IRE gene sequences. included TTTtACTTTC, TTTCAtTTTC, TTTtAtTTTC, TTTtACTTTt and cTTtACcTTC, were found in 22 cases (35.5%), 1 case (1.6%), 1 case (1.6%), 2 cases (3.2%) and 1 case (1.6%) respectively. There were 41.9%cases (26/62) with forth base C→T mutation, consisted of 32.5% (13/40) cases in response group and 59.1% (13/22) cases in NR group. Among the 35 cases with IRE sequences, there were 67.5% (27/40) cases in response group and 36.4% (8/22) in NR group, and the difference in IRE sequences between two groups was statistic significantly (P = 0.027). The result suggested that there is likely relationship between the forth base mutation (C→T) of IRE region and the response of HBV to Interferon therapy, and this mutation may partially decrease the inhibition effect of interferon on HBV.</p> <p>Conclusion</p> <p>The forth base C→T mutation in IRE element of HBV may partially influence the response of Interferon treatment in CHB patients.</p

Forest Soil Heterogeneity and Soil Sampling Protocols on Limestone Outctops: Example from SW China

Forest soil heterogeneity of outcrop karst was studied by testing soil organic carbon at a selected 20 m × 30 m plot set up in Maolan primitive karst forest area, southern Guizhou Province, China. 90 microhabitats in the plot are roughly classified into 7 distinct microhabitat There was great heterogeneity in the plot not only for soil distribution but for great difference of soil organic carbon content. Soil organic carbon (SOC) contents were much higher, ranging from 40.1 g/kg to 203.5 g/kg. The CV (coefficient of variation) value of SOC from 38 soil sampling points, 22 sampling microhabitats, each microhabitat type, and individual microhabitat was 43%, 41%, 2.2% to 42%, 14% to 57.3% respectively. This showed high soil heterogeneity in terms of soil distributing pattern, size and soil organic carbon SOC content in outcropped karst. Different methods were applied to calculate SOC content in the plot. Small discrepancies suggested that the mixed soil samples collected from the major microhabitat types covering 95% soil distributing area were capable of representing soil nutrient status of the whole plot