A Low-Load QoS Routing Method for OpenFlow Networks

As the volume of Internet traffic continues to grow, there is a need for mechanisms that ensure communication quality that is suitable for different applications. OpenFlow implements per-flow routing control but can have adverse effects on communication quality when the number of flow entries is increased. In this study, we propose a routing method that controls traffic flows by labeling them with numbers representing the source switch, destination switch and required communication quality. The OpenFlow controller then sets up flow entries on a per-label basis rather than on a per-flow basis, allowing it to reduce the number of flow entries. In an evaluation test, we confirmed that the labeling method could prevent this reduction in communication quality.

Route Search Method for Railway Replacement Buses Adopting Ant Colony Optimization

In recent years, Japan, and especially rural areas have faced the growing problems of debt-ridden local railway lines along with the population decline and aging population. Therefore, it is best to consider the discontinuation of local railway lines and introduce replacement buses to secure the transportation methods of the local people especially in rural areas. Based on the above background, targeting local railway lines that may be discontinued in the near future, appropriate bus stops when provided with potential bus stops were selected, the present study proposed a method that introduces routes for railway replacement buses adopting ant colony optimization (ACO). The improved ACO was designed and developed based on the requirements set concerning the route length, number of turns, road width, accessibility of railway lines and zones without bus stops as well as the constraint conditions concerning the route length, number of turns and zones without bus stops. Original road network data were generated and processed adopting a geographic information systems (GIS), and these are used to search for the optimal route for railway replacement buses adopting the improved ACO concerning the 8 zones on the target railway line (JR Kakogawa line). By comparing the improved ACO with Dijkstra’s algorithm, its relevance was verified and areas needing further improvements were revealed.

Hydraulic model with roughness coefficient updating method based on Kalman filter for channel flood forecast

A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness updating technique was developed using the Kalman filter method to update Manning＇s roughness coefficient at each time step of the calculation processes. Channel shapes were simplified as rectangles, triangles, and parabolas, and the relationships between hydraulic radius and water depth were developed for plain rivers. Based on the relationship between the Froude number and the inertia terms of the momentum equation in the Saint-Venant equations, the relationship between Manning＇s roughness coefficient and water depth was obtained. Using the channel of the Huaihe River from Wangjiaba to Lutaizi stations as a case, to test the performance and rationality of the present flood routing model, the original hydraulic model was compared with the developed model. Results show that the stage hydrographs calculated by the developed flood routing model with the updated Manning＇s roughness coefficient have a good agreement with the observed stage hydrographs. This model performs better than the original hydraulic model.

Evaluation of repeated exposure systemic toxicity test of PVC with new plasticizer on rats via dual parenteral routes

Systemic toxicity caused by repeated exposure to both polar and nonpolar leachables of di(2-ethylhexyl)-1,2-cyclohexane plasticized polyvinyl chloride(PVC)was evaluated with dual routes of parenteral administration method on rats in the study.Experimental group and control group were designed by researchers.Tail intravenous injection with 0.9%sodium chloride injection extracts and intraperitoneal injection with corn oil extracts were conducted to the experimental rats while tail intravenous injection with 0.9%sodium chloride Injection and intraperitoneal injection with corn oil were conducted to the control rats.After 14 days,blood specimens were collected for clinical pathology(hematology and clinical chemistry)analysis.Selected organs were weighed and a histopathological examination was conducted.As a result,compared with the control animals,there were no toxicity-related changes on the parameters above.The results show that the rats do not show obvious systemic toxicity reaction caused by repeated exposure with dual routes of parenteral administration method on rats after administration with both polar and nonpolar exacts of di(2-ethylhexyl)-1,2-cyclohexane plasticized PVC simultaneously up for 14 days.