Junpei Arai

A selective border-casting zone routing protocol for ad-hoc networks

One of well-known routing protocol for ad hoc networks is zone routing protocol (ZRP). The performance of ZRP is better than other protocols. However, many useless control packets are used resulting in the increase of network load and decrease of network performance. In this paper, we propose a selective border-casting zone routing protocol (SBZRP) to reduce the network load by limiting the number of control packets when the protocol searches for a new route. The performance evaluation via simulations shows that the SBZRP has better performance than ZRP.

Design and implementation of a ubiquitous health monitoring system

In recent years, because of the decline in birth-rate and the growth in the population of elderly people, the lack of doctors and the increase of the medical cost is becoming a big problem. One of solutions for this problem is to prevent the humans from contracting diseases in order to reduce the medical cost (e.g., by using the hospital as few times as possible). In this research, we have developed a wearable vital sensor which can be used anywhere without disrupting the everyday life of the patient. Furthermore, we have implemented a ubiquitous health monitoring system, which can confirm and share the sensor information received from a cellular phone attached to the wearable vital sensor immediately through the browser. This system can also send an emergency report based on sensor information to the family and the doctor. In addition, we verified the systems effectiveness by evaluating the implemented system.

An enhanced zone-based routing protocol for mobile ad-hoc networks based on route reliability

In mobile ad-hoc networks (MANET), the nodes intercommunicate through single-hop and multi-hop paths in a peer-to-peer fashion. Intermediate nodes between two pairs of communication nodes act as routers. Thus the nodes operate both as hosts and routers. The nodes are mobile, so the topology of the network may change rapidly and unexpectedly. One of well-known routing protocol for ad-hoc networks is zone routing protocol (ZRP). However when the protocol searches for a new route, it sends many useless control packets, which increase the network load and decrease the network performance. In this paper, we propose an enhanced zone routing protocol (EZRP). In EZRP, each node calculates the reliability of the route. In the case of reliable route, the source node sends the data packet directly to the destination node using that route without route searching. While, in the case of unreliable route, the source node searches for a new route again. We show that the network performance can be improved by using EZRP.

A GA-based QoS multicast routing algorithm for large-scale networks

For multimedia applications, the routing algorithms should consider many Quality of Service (QoS) parameters. However, to find routes with two or more QoS parameters is an NP-hard problem. Therefore, recently many researchers are trying to use heuristic methods such as Genetic Algorithm (GA). In a previous work, a QoS multicast routing based on GA was proposed. However, in this algorithm, the multicast routing falls in the local minimum and cannot satisfy the application requirements. In this paper, we propose a new QoS multicast routing protocol, which has better genetic operations than the conventional algorithm, resulting in a better performance.

A new quality of service multicast routing protocol based on genetic algorithm

Multicast service is becoming a key requirement of computer networks supporting multimedia applications. For multimedia applications, the routing algorithms should consider many quality of service (QoS) parameters such as delay, cost and so on to find a new route. However, to find routes with two or more QoS parameters is a NP-hard problem. Therefore, many researchers are trying to use heuristic methods such as genetic algorithm (GA) to find good routes satisfying application request. In a previous work, a QoS multicast routing based on GA was proposed. The routing algorithm uses as QoS parameters for multicasting the delay and cost. However, in this algorithm, the multicast routing falls in the local minimum and can not satisfy the application requirement. In this paper, we propose a new QoS multicast routing protocol which has better genetic operations than the conventional algorithm, resulting in a better search success ratio and computation time compared with the conventional algorithm.

AN EFFICIENT MULTI-PURPOSE OPTIMIZATION METHOD FOR QOS ROUTING USING GENETIC ALGORITHM

In order to support multimedia communication, it is necessary to develop routing algorithms that make decisions based on multiple Quality of Service (QoS) parameters. This is because new services such as video on demand and remote meeting systems have multiple QoS requirements. However, the problem of QoS routing is difficult because finding a feasible route with two independent path constraints is NP-complete problem. Also, QoS routing algorithms for broadband networks must be adaptive, flexible, and intelligent for efficient network management. In this paper, we propose a multi-purpose optimization method for QoS routing based on Genetic Algorithm (GA). The simulation results show that the proposed method has a good performance and therefore is a promising method for QoS routing.

An adaptive reservation time division multiple access control protocol for robot inter-communication

In autonomous distributed robot systems, many robots cooperate together to carry out many difficult tasks that single robots cannot realise. But, in order to cooperate together the robots should communicate with each other. Therefore, the inter-communication among robots is a very important problem to be solved. In this paper, we propose an Adaptive Reservation-Time Division Multiple Access (AR-TDMA) medium access control protocol which can realise a real-time communication among robots in a heterogeneous environment by using a reservation mechanism. Also, by using an adaptive time slot allocation method, the protocol has a flexible behaviour and can deal with the changes of number of robots. Furthermore, the proposed protocol can reduce the packet collision probability.

Implementation and Evaluation of a Ubiquitous Health Monitoring System

In recent years, because of the birthrate declining and the elderly people’s population growing, the lack of doctors and the increase of the medical cost is becoming a big problem. One of solution for this problem is to prevent the humans from diseases in order to reduce the medical cost (e.g. by using the hospital as few times as possible). In this research, we have developed a wearable vital sensor which can be used anywhere without disrupting the everyday life of the patient. Furthermore, we have implemented a ubiquitous health monitoring system, which can confirm and share the sensor information received from a cellular phone attached to the wearable vital sensor immediately through the browser. This system can also send emergency report based on sensor information to the family and the doctor. In addition, we verified the system effectiveness by evaluating the implemented system.

Design and Implementation of a Remote Medical-Care Supporting System

In the last few years we have observed an explosive growth of multimedia computing, communication and applications. Information technology (IT) has a great effect in our everyday life and is transforming the way people live, work, and interact with each other, and is impacting the way businesses, government services, education, entertainment, and medical-care are operating. In this research, we propose and develop a remote medical-care system for supporting nurses, care managers and care helpers during their work. The proposed system has three functions: a multi-point communication function using video images and voice, vital signs data auto-uploading and referring function, and a drip infusion monitoring function. In this paper, we present the proposed remote medical-care support system

Performance Evaluation of Load-Balancing Multi-path Routing Protocol for Mobile Ad-Hoc Networks

An ad hoc network is composed by autonomous, potentially mobile, wireless nodes that operate without the benefit of any existing infrastructure. Each node is can move arbitrary and carries out self-administration and self-organization. For this reason, there are cases in which non-planned routes construction may lead to a decline of the network performance. In this paper, we present a new routing protocol that uses the load balancing and multi-path solution to send data with a probabilistic dispersion. In this research, the total load on a route is evaluated based on the relay nodes queue size. Simulation experiments have been made to compare some of the existing protocols with the proposed routing protocol. We have shown by simulations results that our proposed solution efficiently disperses the load and improves the network performance.