• Transactions of the Korean Society of Automotive Engineers
• /
• v.15 no.1
• /
• pp.8-15
• /
• 2007

Freeway corridors consist of urban freeways and parallel arterials that drivers can use alternatively. Ramp metering in freeways and signal control in arterials are contemporary traffic control methods that have been developed and applied in order to improve traffic conditions of freeway corridors. However, most of the existing studies have focused on either optimal ramp metering in freeways, or progression signal strategies between arterial intersections. There have been no traffic control systems in Korea that integrates the freeway ramp metering and arterial signal control. The effective control strategies for freeway operations may cause negative effects on arterial traffic. On the other hand, traffic congestion and bottleneck phenomenon of arterials due to the increasing peak-hour travel demand and ineffective signal operation may generate an accessibility problem to freeway ramps. Thus, the main function of the freeway which is the through-traffic process has not been successful. The purpose of this study is to develop an integrated control model that connects freeway ramp metering systems and signal control systems in arterial intersections. And Optimization of integrated control model which consists of ramp metering and signal control is another purpose. The design of experiment, neural network, and simulated annealing are used for optimization.

• Journal of Internet Computing and Services
• /
• v.7 no.6
• /
• pp.51-62
• /
• 2006

The load of this kind of gores, which is heavier than that of any other precedent, and on enormous seamless virtual world characterize the MMORPG(Massively Multiplayer Online Role-Playing Game) genres. In this seamless environment, gamers can usually accept a set of independent spaces, which is being held by independent game servers, os a single big virtual world. Despite the efforts of some developers, gamers are suffered from huge message traffic which comes from the interaction between client and server and the interaction between fold sowers. In this paper, new gore server architecture using MigAgent is proposed which tries to reduce message traffic. Usually, message traffic reaches the climax when a PC(Player Character) is moving to other field server. MigAgent, designed in this thesis, tries to manage this kind of PCs and to ploy o role of user's agent to prepare for the unexpected situation. Improvement of this system is shown by the analysis of the effect of the size ratio of AOI (Area of Interest) and AC (Adjacent Cell).

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.1735-1740
• /
• 2005

In this paper, ways of improving the performances of roundabouts under the assumption that the Advanced Vehicle System is proposed. The situation on a road contains uncertainty and complexity caused by different vehicles having different directions and time-varying traffic flow. This sort of system with high uncertainty is called Multi Agent System (MAS). The MAS is a collective system, including numbers of agents and performs high diversity of the configuration as well as it has nonlinear property and complexity. Hence it is difficult to analyze and control the multi-agent system. A roundabout can be considered as an MAS with numbers of moving vehicles. So it must be difficult to use a centralized control technique to all vehicles in an intersection. Therefore, to improve the performances of roundabouts, multi-agents flow control algorithm for vehicles in Roundabouts using 'self-organization' technique is proposed.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.6 no.7
• /
• pp.993-1000
• /
• 2002

In this paper, we design the CORBA-based Mobile Agent Model (CMAM) which has the capability of the efficient work processing in distributed environment through sensing network traffic and searching the optimal path for migration nodes of mobile agent. In case existing mobile agent model is given various works from user, the network overhead and traffic are increased by increasing of execution module size. Also, if it happens a large quantity of traffics due to migration of nodes according to appointment of the passive host(below node) routing schedule by user, it needs much cost for node search time by traffic. Therefore, in this paper, we design a new mobile agent m()del that assures the reliability of agent's migration through dynamic act on the specific situation according to appointment of the active routing schedule and can minimize agent's work processing time through optimal path search. The proposed model assigns routing schedule of the migration nodes actively using an extended MAFFinder. Also, for decreasing overhead of network by agent's size, it separates the existing mobile agent object by mobile agent including only agent calling module and push agent with work executing module based on distributed object type of CORBA. Also, it reduces the required time for round works of mobile agent through the optimal path search of migration nodes.

• Journal of Navigation and Port Research
• /
• v.44 no.6
• /
• pp.469-476
• /
• 2020

Modeling and Simulation (M&S) systems which deal with situational complexity often require human involvement due to the high-level decision-making that is necessary for ship movement, navigation, control center management, shipping company logistics, meteorological system information, and maritime transportation GIS. In order to properly simulate maritime traffic, it is necessary to accurately model the human decision-making process of the ship officer, including aspects of the ship officer's behavioral tendencies, personal navigation experience, and pattern of voyage errors, as this is the most accurate way in which to reproduce and predict realistic maritime traffic conditions. In this paper, which looks at agent-based maritime traffic simulation, we created a basic survey in order to conduct behavior analysis on ship operators' collision avoidance strategies. Using the information gathered throughout the survey, we developed an agent-based navigational behavior model which attempts to capture the behavioral patterns of a ship officer during an instance of ship collision. These results could be used in the future in further developments for more advanced maritime traffic simulation.

• Journal of the Korea Society of Computer and Information
• /
• v.5 no.4
• /
• pp.120-125
• /
• 2000

SNMP(Simple Network Management Protocol) could have the overhead of network, if the number of the agent system which is managed by the management system is increased by the polling for the collection of network management information and the reply traffic for it. In this Paper, the polling method used in SNMP is improved, and Group Polling method is proposed. This can reduce the overhead of network, on case that the agent system is to be increased. The proposed method collects information by grouping agent systems, and have smaller reply latency time and communication overhead than the previous method. So if the number of agent system or the Polling count is numerous, the proposed method is more efficient. As the result of the prototype test, the increasement of agent system can have small variation of traffic and transmission delay time.

• Proceedings of the IEEK Conference
• /
• 2002.06a
• /
• pp.105-108
• /
• 2002

This paper analytical models of a centralized approach based on SNMP Protocol, distributed approach based on mobile agent, and mixed model which is tile existing mobile agent model in order to overcome large communication numbers of SNMP and accumulated data of mobile agent. And then, we compare and analyze these analytical models. Performance evaluation results show that performance of mobile agent and the mixed model is less sensitive to the network traffic and more profitable for complex network environment than that of SNMP.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2002.11a
• /
• pp.550-554
• /
• 2002

In this paper, we design the CORBA-based Mobile-Agent Model (CMAM) which has the capability of the efficient work processing in distributed environment through sensing network traffic and searching the optimal path for migration nodes of mobile agent. In case existing mobile agent model is given various works from user, the network overhead and traffic are increased by increasing of execution module size. Also, if it happens a large quantity of traffics due to migration of nodes according to appointment of the passive host(node) muting schedule by user, it needs much cost for node search time by traffic. Therefore, in this paper, we design a new mobile agent model that assures the reliability of agent's migration through dynamic act on the specific situation according to appointment of the active routing schedule and can minimize agent's work processing time through optimal path search. The proposed model assigns routing schedule of the migration nodes actively using an extended MAFFinder. Also, for decreasing overhead of network by agent's size, it separated by mobile agent including oかy agent calling module and push agent with work executing module based on distributed object type of CORBA. Also, it can reduce the required time for round works of mobile agent through the optimal path search of migration nodes.

• Journal of the Korea Society of Computer and Information
• /
• v.11 no.3
• /
• pp.117-124
• /
• 2006

In this paper, we propose the optimal migration path searching method including path adjustment and reassignment techniques for an efficient migration of mobile agent which has an autonomous ability for some task processing. In traditional agent system, if the various and large quantify of task processing were required from the users, it could be derive excessive network traffic and overload due to increasing the size of agent. And also, if an agent migrates from node to node according to routing schedules specified by the user at which the most of network traffic occurs, it could not actively cope with particular situations such as communication loss and node obstacles and required much cost for node traversal Therefore. this paper presents the migration method of agent which can try to adjust and reassign path to the destination automatically through the optimal path search using by network traffic perception in stead of the passive routing schedule by the user. An optimal migration path searching and adjustment methods ensure the migration reliability on distributed nodes and reduce the traversal task processing time of mobile agent by avoiding network traffic paths and node obstacles.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.5
• /
• pp.91-98
• /
• 2020

The mobile agent, which handles a given task while migrating between the sensor nodes, moves including the execution commands and task processing results. This increases the size of the mobile agent, causing the network to load, leading to the migration time delay and the loss of migration reliability. This paper presents the method of lightening the mobile agent using distributed object technology and the algorithm for exploring and providing the optimal migration path that is actively performed in the event of network traffic, and it proposes a method to ensure the reliability of the mobile agent migration by applying them. In addition, through the comparative analysis experiments based on agent size and network traffic for the migration time of mobile agent equipped with active rules in sensor network-based mobile agent middleware environment, applying the proposed methods proves to ensure the autonomy and migration reliability of the mobile agent.