• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.7
• /
• pp.2488-2511
• /
• 2015

Data redundancy has high impact on Wireless Sensor Network's (WSN) performance and reliability. Spatial and temporal similarity is an inherent property of sensory data. By reducing this spatio-temporal data redundancy, substantial amount of nodal energy and bandwidth can be conserved. Most of the data gathering approaches use either temporal correlation or spatial correlation to minimize data redundancy. In Collective Prediction exploiting Spatio Temporal correlation (CoPeST), we exploit both the spatial and temporal correlation between sensory data. In the proposed work, the spatial redundancy of sensor data is reduced by similarity based sub clustering, where closely correlated sensor nodes are represented by a single representative node. The temporal redundancy is reduced by model based prediction approach, where only a subset of sensor data is transmitted and the rest is predicted. The proposed work reduces substantial amount of energy expensive communication, while maintaining the data within user define error threshold. Being a distributed approach, the proposed work is highly scalable. The work achieves up to 65% data reduction in a periodical data gathering system with an error tolerance of 0.6℃ on collected data.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.10
• /
• pp.137-145
• /
• 2010

This paper is proposed non-contact plant growth measurement system using infrared sensor based on USN(Ubiquitous Sensor Network) technologies. The proposed system has used noncontact sensors to reduce any potential damage when it measures the growth of the plant. In this system, plant growth parameters such as diameter, cross-sectional area and thickening form are measured in real-time non-contact method. The measured data are transmitted to remote server by using sensor network technologies, stored and analyzed at the server, and the analyzed data are finally provided for users. In this paper, the proposed plant growth measurement system has been designed and implemented using non-contact infrared sensor based measurement methods and devices, and its performances have been verified by actual measurement experiments at the fields.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.10 no.5
• /
• pp.287-291
• /
• 2010

In this paper, we designed and implemented mobile object automatic system based on senor networks for telematics. For developing this system, we gather the various sensing data through wireless communication method using zigbee sensor networks and analyze them in monitoring equipment. And we enable the driver to recognize the car state information on the whole by interfacing analyzed data to telematics unit. And, we implemented automatic controller that can control temperature and humidity in car automatically by actuating air conditioner based on the data that was monitored throughout temperature sensor, humidity sensor and brightness sensor based on sensor networks.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.6 no.2
• /
• pp.161-166
• /
• 2006

Localization of mobile agent within a sensing network is a fundamental requirement for many applications, using networked navigating systems such as the sonar-sensing system or the visual-sensing system. To fully utilize the strengths of both the sonar and visual sensing systems, This paper describes a networked sensor-based navigation method in an indoor environment for an autonomous mobile robot which can navigate and avoid obstacle. In this method, the self-localization of the robot is done with a model-based vision system using networked sensors, and nonstop navigation is realized by a Kalman filter-based STSF(Space and Time Sensor Fusion) method. Stationary obstacles and moving obstacles are avoided with networked sensor data such as CCD camera and sonar ring. We will report on experiments in a hallway using the Pioneer-DX robot. In addition to that, the localization has inevitable uncertainties in the features and in the robot position estimation. Kalman filter scheme is used for the estimation of the mobile robot localization. And Extensive experiments with a robot and a sensor network confirm the validity of the approach.

• 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 Institute of Control, Robotics and Systems
• /
• v.20 no.10
• /
• pp.1051-1056
• /
• 2014

In this paper, we introduce an intelligent robotic arc welding system which exploits sensors like as LVS (Laser Vision Sensor), Hall effect sensor, voltmeter and so on. The use of industrial robot is saturated because of its own limitation, and one of the major limitations is that industrial robot cannot recognize the environment. Lately, sensor-based environmental awareness research of the industrial robot is performed actively to overcome such limitation, and it can expand application field and improve productivity. We classify the sensor-based intelligent arc welding robot system by the goal and the sensing data. The goals can be categorized into detection of a welding start point, tracking of a welding line and correction of a torch deformation. The Sensing data can be categorized into welding data (i.e. current, voltage and short circuit detection) and displacement data (i.e. distance, position). This paper covers not only the explanation of the each category but also its advantage and limitation.

• International Journal of Internet, Broadcasting and Communication
• /
• v.10 no.2
• /
• pp.45-50
• /
• 2018

Recently the water management department advised the water treatment industry to focus on deploy the chemical free and the environmentally responsible process to adopt on water treatment plants in every country. In this objective, water treatment process started using ultrasonic based phycocyanin extraction with fluorescence measurement techniques to detect the change in the yield of phycocyanin. This paper propose the design of optical filter model for fluorescence technique based immersive optical phycocyanin measurement sensor design. The proposed design uses the multi-wavelength sensor module for irradiating part, and this plays a role of removing a wavelength band other than 590 ~ 620 nm. The preliminary study on immersed phycocyanin sensor, the fluorescence value of picocyanin according to the ultrasonic intensity, treatment time and number of cells was measured using JM phycocyanin module to emulate the proposed design, and were compared performance of the proposed sensor emulation. In this design, the phycocyanin fluorescence value increased about 2.1 ~ 4.7 times as the ultrasonic treatment time increased as compared with JM phycocyanin module, and the phycocyanin fluorescence value within the analysis range was obtained by ultrasonic treatment within one minute.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.06a
• /
• pp.390-390
• /
• 2008

In this paper, we have designed and fabricated optical waveguides based on the Mach-Zehnder Interferometer (MZI) for application to sensor. The evanecent-wave sensor based on the MZI principle has sufficiently high sensitivity to measure the change of the refractive index on surface of a waveguide. The waveguides were optimized at a wavelength of 1550 nm and fabricated according to the design rule of 0.45 delta%, which is the difference of refractive index between the core and clad. The fabrication of MZI optical waveguides was performed by a conventional Planar Lightwave Circuit (PLC) fabrication process. The fabricated MZI optical waveguide device was measured. According to the measurement result, the insertion loss of MZI optical waveguide device was below 3.5 dB and the polarization dependent loss (PDL) was within 0.1dB. In addition, we analyzed optical properties of MZI sensor according to the refractive index change of the sensor arm.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39C no.1
• /
• pp.90-96
• /
• 2014

IEEE802.15.4 that is a standard for sensor networks is mainly used the wireless personal area networks such as ZigBee networks and it features low-power, low-speed data communication. However, recently research for interworking sensor network based voice communication and Session Initiation Protocol (SIP) for long-range, multi-user support has been actively conducted. In this paper, we designed a integrated base station based existing systems for interworking sensor networks based voice communication and SIP. We measured number of packet and delay according to increase the number of users to evaluate the performance of designed Base Station.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.24 no.2
• /
• pp.174-182
• /
• 2012

In previous research, most occupant said that they have not operated ventilation system installed in the house, because of increasing of energy consumption and unconcern of ventilation. Therefore, it is necessary to applied the sensor based demand controlled ventilation for the IAQ(Indoor Air Quality) and improvement of energy efficiency in ventilation strategy. The propose of this study is to present a application method of IR(Infrared) sensor for multi-zone DCV(Demand Controlled Ventilation) in the apartment house. It is possible that IR sensor could be used for DCV, because that could detect the occupant and action. IR sensor based DCV strategies are established to evaluate characteristic of application in the apartment house and simulated by Contam program. As a result, they have some week points though, if they would be applied DCV with optimum strategy, it would be useful to improve IAQ, to reduce energy consumption.