• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.6
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• pp.1215-1221
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• 2009

A novel approach for electrocardiogram (ECG) analysis within a functional sensor node has been developed and evaluated. The main aim is to reduce data collision, traffic overload and power consumption in healthcare applications of wireless sensor networks(WSN). The sensor node attached on the patient's body surface around the heart can perform ECG analysis based on a QRS detection algorithm to detect abnormal condition of the patient. Data transfer is activated only after detected abnormality in the ECG. This system can reduce packet loss during transmission by reducing traffic overload. In addition, it saves power supply energy leading to more reliable, cheap and user-friendly operation in the WSN for ubiquitous health monitoring.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.6
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• pp.688-692
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• 2010

Wireless sensor network system collects and analyzes real-time data that have been requested by the many application nodes. This paper has constructed a sensor network cluster with various elements in the Gunsan City area of Jeollabuk-do, S.korea. The purpose of this paper is to utilize the constructed system in order to illustrate the real-time data in a diagram and analyze it to deduce the change ratio. The resulting analysis contents allow simple data interpretation by illustrating the data in change ratio by time, space, and motional directions. This analytical method will offer great benefit to those users using the wireless sensor network.

• Journal of Convergence Society for SMB
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• v.4 no.4
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• pp.1-6
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• 2014

A wireless sensor network is being actively researched around the world that are connected to the mesh are a plurality of sensor nodes in a wireless manner that span different regions of the techniques. However, wireless communications use the limitation of resources, so it is very weak due to the properties of the network itself secure in comparison to the normal network. Wireless sensor network is divided into tapped-based attacks, forgery based attacks, denial of service attacks based largely by securities laws must defend against various attacks such as insertion of the wrong information being sent eavesdropping or modification of information, which is usually sensor network applications need to do. The countermeasure of sensor network attack is described in this research, and it will contribute to establish a secure sensor network communication.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.768-774
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• 2007

This paper proposes how to reduce the amount of data transmitted in each sensor and cluster head in order to lengthen the lifetime of sensor network. This study proposes hierarchical filtering for reducing the sensor's energy dissipation. Hierarchical filtering is to divide sensor network by two tiers when filtering it. First tier performs filtering when transmitting the data from cluster member to cluster head, and second tier performs filtering when transmitting the data from cluster head to base station. This should increase the efficiency of filtering and decrease the inaccuracy of the data compared to the methods which enlarge the filter width to do more filtering.

• Prospectives of Industrial Chemistry
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• v.21 no.1
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• pp.3-18
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• 2018

전자피부(Electronic skin)는 외부 환경과의 상호작용하는 인간 피부의 기능을 대체하여 외부 자극 신호를 전기적 신호로 변환하는 센서들로 이루어진 인공피부로써, 최근 인간과 전자기기 간의 인터페이스에 대한 관심이 급증하면서 이에 대한 많은 연구들이 진행되고 있다. 그중에서도 피부의 주된 기능인 외부 물리적 자극을 인지하는 촉각을 모방하는 촉각센서는 많은 발전을 거쳐 왔으며, 한계를 극복하고자 다양한 연구들이 진행되고 있다. 촉각센서는 압력, 인장, 굽힘과 같은 물리적 자극에 반응하며, 물리적 자극 신호를 아날로그 및 디지털 신호로 변환하여 인지하는 연구들이 폭넓게 개발되고 있다. 또한, 소자의 구조에 따라 물리적 자극을 전달하는 다양한 변환 방식들이 있으며, 최근에는 각 신호 변환 방식의 민감도, 반응속도, 자극 인지 범위 등의 한계점을 극복하고, 소재의 기계적 물성을 향상시키기 위해 소재의 변형을 주거나 생체의 기관 구조 및 외부 자극 인지 원리 등을 모사한 연구들이 많은 관심을 받고 있다. 본 기고에서는 이러한 촉각센서의 물리적 자극 신호 변환 방식과 소재 변형 및 생체 모사를 통한 다양한 연구들을 소개하고자 하며, 이를 통하여 촉각센서의 나아갈 방향을 제시하고자 한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.11a
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• pp.815-818
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• 2007

최근 유비쿼터스 시대가 도래하면서 센서 네트워크의 중요성이 대두되고 있다. 센서 네트워크란 필요한 모든 곳에 전자태그를 부착하고, 이를 통해 사물의 인식 정보를 기본으로 주변의 환경정보까지 각종 센서를 통해 실시간으로 수집하여 관리, 통제할 수 있도록 구성한 네트워크를 말한다. 이러한 센서 네트워크에서 각 노드들은 에너지, 계산 능력, 대역폭 등에 상당한 제한을 받으며, 정보가 저장된 장치를 쉽게 도난 당할 수도 있다. 특히 보안 통신을 하기 위해 키 설정 및 관리는 필수적이며 지금까지 그로 인해 여러 가지 키 분배 및 관리 방법이 제안되었다. 본 논문은 군대 등의 특정 상황과 같이 계층적 구조를 가지는 센서 네트워크에서 더욱 효율적으로 통신을 할 수 있는 키 관리 방법을 소개하고자 한다. 기존의 계층적 구조의 취약점을 분석하고, 이를 바탕으로 레벨 키를 제안하여 같은 레벨에서 다른 그룹간 통신이 가능한 효율적인 키 분배 방안을 제시한다.

• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.180-181
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• 2008

Recently, USN applications are in the early stage of commercialization. But, there are still several problems to develop USN applications. It is mainly due to the current development scheme that solution vendors makes all of them including HW, SW, sensor modules. The development of USN applications could be revitalized if three entities such as PC platform developers, PC device vendors, and application developers would do their best as in PC development. In this paper, we suggest an sensor node platform architecture supporting sensor independency to overcome the difficulty of developing USN applications. Traditional platforms like Tiny-OS and Nano-Q+ do not support such sensor independency. At first, we present a unified API for sensor independency, and also suggest an architecture to support sensor independancy. Our architecture results in the revitalization of developing USN applications.

• Journal of Industrial Technology
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• v.30 no.B
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• pp.55-59
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• 2010

The number of elderly people living alone increases with the trend of nuclear family in recent aging society and advances of health and medical technologies, where the safety of the elderly people becomes a big social issue. One of the safety system for them these days is that security guards regularly visit homes of the elderly living alone to check their safety. However, it is an inefficient system since it costs a great deal. So, a new efficient system with low cost using modern advanced technologies needs to be developed. In this paper, we implement a monitoring system for elderly living alone using ubiquitous sensor and zigbeX. The system can remotely determine the health status of elderly people and report to their hospitals. Since the system can be implemented with low cost and do the same job as security guards do, we expect that it should replace the existing expensive monitoring system.

• Journal of Sensor Science and Technology
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• v.14 no.6
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• pp.444-454
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• 2005

The IEEE 1451.4 standards defines an architectural model for interfacing smart transducers for sensors & actuators. This standard allows analogue transducers to communicate their identification and calibration data in a digital format. A digital format is called the TEDS (transducer electronic data sheet). However, the standard template TEDS of IEEE 1451.4 do not supports sensors to use in electronic tongue system, such as arrayed-potentiometric and voltametric sensors. In this paper, a solution to standardize sensors for E-Tongue (electronic tongue) and electronic tongue systems is presented.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.123-124
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• 2002

최근 인간의 생활환경에 존재하는 유해가스 및 대기환경에 대한 관심이 고조되면서 환경유해가스를 손쉽게 감지할 수 있는 센서의 필요성이 중요하게 인식되고 있다. 그 중 암모니아 가스는 생활환경 내에 존재하는 악취성분일 뿐만 아니라 냉각기의 냉매로 사용되는 가스로써 대기 중 배출허용농도가 50ppm으로 알려져 있다. (중략)