• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2132-2134
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• 2002

최근 분산제어시스템 설계시 CAN(Controller Area Network)을 적용하는 연구가 활발히 진행되고 있다. 본 논문에서는 분산제어에 필요한 각종 입출력 데이터를 CAN버스 상에서 송수신할 수 있는 Smart Sensor/Actuator Node를 직접 개발하고, 이를 이용한 실험용 Network를 구축하였다. Sensor Node에서 획득된 외부의 Analog신호를 CAN Bus를 통해 전송한 후, 원격지의 Actuator Node에서 출력하는 Data 송수신 실험을 통해서 설계된 Network와 각 Node의 효율성을 입증하였다.

• Journal of IKEEE
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• v.20 no.4
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• pp.449-453
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• 2016

Failures would occur because of the hostile nature environment in Wireless Sensor Networks (WSNs) which is deployed randomly. Therefore, considering faults in WSNs is essential when we design WSN. This paper classified fault model in the sensor node. Especially, this paper proposed new error correcting code scheme and fault recovery algorithm in the CH(Cluster Head) node. For the range of the small size information (<16), the parity size of the proposed code scheme has the same parity length compared with the Hamming code, and it has a benefit to generate code word very simple way. This is very essential to maintain reliability in WSN with increase power efficiency.

• Journal of Sensor Science and Technology
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• v.16 no.5
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• pp.361-368
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• 2007

Small size real-time ECG signal analysis function by QRS-complex detection was put into sensor nodes. Wireless sensor nodes attached on the patient’s body transmit ECG data continuously in normal u-healthcare system. So there are heavy communication traffics between sensor nodes and gateways. New developed platform for real-time analysis of ECG signals on sensor node can be used as an advanced diagnosis and alarming system for healthcare. Sensor node does not need to transmit ECG data all the time in wireless sensor network and to server PC via gateway. When sensor node detects suspicion or abnormality in ECG, then the ECG data in the network was transmitted to the server PC for further powerful analysis. This system can reduce data packet overload and save some power in wireless sensor network. It can also increase the server performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.7
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• pp.1549-1555
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• 2009

The Relay node placement problem is one of the most important requirements for many wireless sensor networks because the lifetime of sensor networks is closely related with the placement of relay nodes which receive sensed data from sensor nodes and forward them to the base station. Relay node placement problem has focused at minimization of dissipated total energy of the sensor nodes in whole networks. However, minimum total energy causes the unbalance of consumed energy in sensor nodes due to different distances between relay nodes and sensor nodes. This paper proposes the concept of energy balance ratio and finds the locations of relay nodes using objective functions which maximize the energy balance ratio. Maximizing this ratio results in maximizing the network lifetime by minimizing the energy consumption of large-scale sensor networks. However, finding a solution to relay node placement problem is NP-hard and it is very difficult to get exact solutions. Therefore, we get approximate solutions to EBR-RNP problem which considers both energy balance ratio and relay node placement using constraint programming.

• Fire Science and Engineering
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• v.23 no.6
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• pp.75-81
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• 2009

In this paper, USN of wireless communication with easy to install and effectiveness with variety information gathering has been proposed as a alternative of wired-based line for transmission of fire sensing data. But, The sensor node using USN should be considered for wireless transmission range and reliability of information. In this study, the zigbee protocol sensor node was implemented and then tested transmission range of sensor node as 10m interval using voltage information of DC 3V & 5V. Here, maximum transmission distance was confirmed 90m inside-outside. When used mesh routing relay node, distance was not limited. In USN network building, when fire sensing data transmitted, the sensing data same between direct sensing data from sensor and collecting data at USN. Therefore, was confirmed reliability for transmission range and information of proposed zigbee sensor node.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.6
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• pp.761-769
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• 2012

In this paper, we propose a low-power design strategy to minimize energy-consumption for surveillance and reconnaissance sensor networks. The sensor network consists of many different nodes with various operations such as target detection, packet relay, video monitoring, changing protocols, and etc. Each sensor node consists of sensing, computing, communication, and power components. These components are integrated on a single or multiple boards. Therefore, the power consumption of each component can be different on various operation types. First, we identified the list of components and measured power consumption for them from the first prototype nodes. Next, we focus on which components are the main sources of energy consumption. We propose many energy-efficient approaches to reduce energy consumption for each operation type.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.1035-1037
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• 2009

Common to use fixed-node sensor network and wireless sensor networks, unlike the recent move of the node happens frequently. These wireless sensor networks by taking into account the mobility of sensor nodes dynamically self-configurable routing protocol is required. In this paper, a fixed-node configuration and energy efficiency in the self-LEACH protocol is based on the useful movement of the nodes of the cluster is dynamically self-configuring routing protocols offer M-LEACH.

• Journal of Advanced Navigation Technology
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• v.14 no.2
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• pp.227-232
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• 2010

According to the development of ubiquitous and computer techniques, the application fields of sensor network have been enlarged. We present the design and implementation of sensor node which is the most important component of sensor network techniques in this paper. The proposed sensor node is implemented with 8-bit microprocessor, and temperature and humidity sensing device to gather temperature and humidity data in real world. It achieves low production cost and user convenience, and also has the feature os existing commercial sensor node. Though our experiments, we show that deviation of temperature and humidity are $5^{\circ}C$ and 23.2% respectively, and the proposed sensor node is reliable in real applications.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.10
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• pp.1905-1913
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• 2006

The researches about the hardware and the software implementing ubiquitous sensor network have great rush in recent years. This paper deals the development of a sensor node with the dual interface which also has an RF wireless interface while has an Bluetooth interface used widely in present. This sensor node includes a Atmeg32 microcontroller, a Bluetooth module, a RF module. a temperature-humidity sensor. and I also develop the F/Ws controlling each modules with C language using GCC compiler. The sensor node developed can reaches 15m with Bluetooth interface and 60m with RF interface. It works stably with the voltage above 5V and it consumes currents 21mA average in idle mode, 63mA average in active mode.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.9A
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• pp.884-891
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• 2006

A wireless sensor node is typically battery operated and energy constrained. Therefore it is critical to design efficient power management technique and scheduling technique. In this paper, we propose an OS-level power management technique for energy saving of wireless sensor node, it is called EA-SENTAS (Energy-Aware Sensor Node TAsk Scheduling). It can decrease the energy consumption of a wireless sensor node to use task scheduling technique that shut down components or use low power mode of each component when not needed. Simulation results show that EA-SENTAS saves energy up to 56 percent to compare with conventional duty cycle.