• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.915-919
• /
• 2005

It is materialized an unmanned vehicle system as a part of Intelligent Transportation System (ITS) which is a fundamental constituent for unmanned vehicle. Remote control system, monitoring system and remote operating system which are consisted of unmanned vehicle system. Network program by TCP/IP socket, and real-time control & operating controlled by servo-motors from a remote place, those are used to verify safety and stability of the unmanned vehicle system in this research. This unmanned vehicle is divided into two major sections which are an unmanned vehicle part and control station part. The server PC is installed on the unmanned vehicle and a client PC is installed at a remote place, which can control the u manned vehicle. In this research work, main theme is that we experimented and tested to check the speed and utilization of the wireless LAN communication.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.9
• /
• pp.4341-4348
• /
• 2012

This paper presents a web-based real-time monitoring system for a photobioreactor using an WiFi wireless network. An WiFi interface can support high speed data transfer, up to 11Mbps and it can be compatible with commercial wireless LAN environment. Thus, the proposed cell culture based on WiFi network can be easily applied to the reconfigurable system and real-time monitoring system. In this paper, we integrate the commercial WiFi module to the various bio-sensors and sensor control board to configure the wireless network. After we evaluate application S/W for monitoring the environment within incubator, we verify the proposed sensor networks for a cell culture system and its monitoring system. This result can be applicable for various bio-applications that require the network configuration and real-time monitoring system.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.1
• /
• pp.202-208
• /
• 2015

A wireless ship area network is required to configure and control various sensors and electrical instruments embedded or boarded in a ship. In such environment, wireless communication protocol adopting relaying function is needed because direct link or communication between two nodes is hardly guaranteed due to spatial constraints in a ship. In this study, we introduce and analyze a WiMedia Distributed MAC (D-MAC) based approach considering throughput and energy constraint of wireless communication module. Performance evaluation results demonstrate that the relay-based wireless communication protocol improves reliability of wireless communication network in a ship.

• Industrial Engineering and Management Systems
• /
• v.15 no.3
• /
• pp.259-267
• /
• 2016

In Wireless Sensor Network, various routing protocols were employed by our Research and Development community to improve the energy efficiency of a network as well as to control the traffic by considering the terms, i.e. Packet delivery rate, the average end-to-end delay, network routing load, average throughput, and total energy consumption. While maintaining network connectivity for a long-term duration, it's necessary that routing protocol must perform in an efficient way. As we discussed Optimized Link State Routing protocol between all of them, we find out that this protocol performs well in the large and dense networks, but with the decrease in network size then scalability of the network decreases. Whenever a link breakage is encountered, OLSR is not able to periodically update its routing table which may create a redundancy problem. To resolve this issue in the OLSR problem of redundancy and predict link breakage, an enhanced protocol, i.e. S-OLSR (More Scalable OLSR) protocol has been proposed. At the end, a comparison among different existing protocols, i.e. DSR, AODV, OLSR with the proposed protocol, i.e. S-OLSR is drawn by using the NS-2 simulator.

• Journal of Institute of Control, Robotics and Systems
• /
• v.10 no.7
• /
• pp.625-633
• /
• 2004

In this paper, position control of a car-like mobile robot using a neural network is presented. positional information of the mobile robot is given by a laser range finder located remotely through wireless communication. The heading angle is measured by a gyro sensor. Considering these two sensor information as a reference, the robot posture is corrected by a cascaded controller. To improve the tracking performance, a neural network with a cascaded controller is used to compensate for any uncertainty in the robot. The neural network functions as a compensator to minimize the positional errors in on-line fashion. A car-like mobile robot is built as a test-bed and experimental studies of several controllers are conducted and compared. Experimental results show that the best position control performance can be achieved by a cascaded controller with a neural network.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.7
• /
• pp.1599-1609
• /
• 2014

TCP does not ensure the bandwidth and delay bound required for multimedia streaming services in broadband wireless network environments. In this paper, we propose a new congestion control scheme for efficient multimedia transmission, called COLO TCP (Concave Increase Slow Start Logarithmic Increase Congestion Avoidance TCP). The COLO TCP prevents the burst packet loss by applying the concave increase algorithm in slow start phase. In the congestion avoidance phase, COLO TCP uses the logarithmic increase algorithm that quickly recovers congestion window after packet loss. To highly utilize network bandwidth and reduce packet loss ratio, COLO TCP uses additive increase algorithm and adaptive decrease algorithm. Through simulation results, we prove that our COLO TCP is more robust for random loss. It is also possible for efficient multimedia transmission.

• Journal of Korea Society of Industrial Information Systems
• /
• v.20 no.4
• /
• pp.47-54
• /
• 2015

With the spread of smart technology, in the personal and office equipment, many of the products are equipped with smart features. These changes have opened the era that can enforce the user's operation from a remote location. In this study, we design and implement a smart multi-plug system to make a multi-plug installed in the home can be operated anytime and anywhere via wireless network technologies add smart feature to a multi-plug that can be seen easily around us, it is intended to complement the limitations of traditional multi-plugs. The smart multi-plug proposed in this paper, by operating the plug remotely from smart devices at anytime and from anywhere, is possible to provide services required for the weak users such as elderly and children, it is expected that the proposed system are widely used in the various areas requiring remote control of the power supply including u-Farming, terrarium, and smart home, and so on.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.5
• /
• pp.57-64
• /
• 2020

In this paper, based on the building's 3D modeling, a digital twin-based building control system using the collection information of wireless sensor box is proposed. The proposed system applies wireless sensors, making sensor modules more expandable and usable, and more intuitive building control possible through three-dimensional modeling. In addition, effective control and visual representation are possible through BIM data. Sensor boxes have been designed for general purpose so that a variety of sensor modules can be added and have been implemented for actual university buildings to demonstrate high availability. The results of this paper could be used to implement a digital twin control platform in the future.

• Journal of Information Technology Applications and Management
• /
• v.14 no.2
• /
• pp.1-10
• /
• 2007

The ubiquitous computing system is expected to be widely utilized in digital home, logistics control, environment/disaster management, medical/health-care services and other applications. The ubiquitous sensor network (USN) is a key infra-structure of this system. Nodes in the USN are exposed to adverse environments and required to perform their missions with very limited power supply only. Also the sensor network is composed of much more nodes. In case some node consumes up its power capacity under a certain required level, the network topology should change and re-routing/ re-transmission of data is necessitated. Resultantly communication protocols studied for conventional wireless networks or ad-hoc networks are not suitable for the sensor network. Schemes should be devised to control the efficient usage of node power in the sensor network. This paper proposes a routing algorithm to enhance the efficiency of power consumption for USN node and analyzes its performance by simulation.

• Journal of information and communication convergence engineering
• /
• v.5 no.3
• /
• pp.200-204
• /
• 2007

The release of IEEE 802.15.4 PHY-MAC standard represents a milestone in developing of commercial wireless sensor network pursuing low power and low cost. In this paper, IEEE 802.15.4 Medium Access Control (MAC) protocol was analysed at the point of power consumption. This analysis measured the amount of the rest of power after transmitting data with beacon enabled mode and the power consumption of each node in the time period. ns-2 simulation is used to verify the analysis.