• Proceedings of the Korean Nuclear Society Conference
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• 1996.05a
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• pp.587-593
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• 1996

Vibration analysis is one of the most powerful tools available for the detection and isolation of incipient faults in mechanical systems. The methods of vibration analysis in use today and under continuous study are broad band vibration monitoring, time domain analysis, and frequency domain analysis. In recent years, great interest has been generated concerning the use of time-frequency representation and its application for a machinery diagnostics and condition monitoring system. The objective of the research described in this paper was to develop a new diagnostic tool for the rotating machinery. This paper introduces a new time-frequency representation, Directional Wigner-Ville Distribution, which analyses the time- frequency structure of the rotating machinery vibration.

• Journal of Energy Engineering
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• v.24 no.2
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• pp.179-186
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• 2015

This study suggests a few solutions to improve the post-monitoring activities under the Energy Efficiency Labeling Program. First, samples should be selected from each category for the post-monitoring activities, taking account of the consumer's continuous buying behavior, while it is also important to form and operate a deliberation committee. Second, it is necessary to alleviate the checking process of the label content of 9 items which have never been violated the labeling regulation since 2005. This study suggests the detailed checking of label contents and the reinforcement of the measurement of 17 items which have violated labeling more than once over the past few years. Third, this study suggests that the entire post-monitoring process should be disclosed and be posted on the websites of related agencies and on the Internet in general.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11B
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• pp.1169-1177
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• 2009

This paper presents an energy efficient MAC protocol for delay-sensitive data transmission over wireless sensor network. In general, energy consumption and delay depend on Channel Monitoring Interval and data sensing period at each sensor node. Based on this fact, we propose a new preamble structure to effectively advertise Channel Monitoring Interval and avoid the overhearing problem. In order to pursue an effective tradeoff between energy consumption and delay, we also develop a Channel Monitoring Interval determining algorithm that searches for a sub-optimal solution with a low computational complexity. Finally, experimental results are provided to compare the proposed MAC protocol with existing sensor MAC protocols.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.6
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• pp.895-902
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• 2018

Energy consumption in buildings is close to 40% of the total national energy consumption in developed countries such as US and Japan, and Korea accounts for 24% of total energy consumption. In buildings, HVAC can't freely control the cooling flow rate according to the required calorie, so energy is not used efficiently. Therefore, by using the energy saving valve, the flow rate can be controlled by the required amount of heat and the energy can be saved. In this paper, we define basic conditions and develop control and monitoring boards for building energy saving valves based on PIC processor with low power and high cost-effectiveness. The designed board displays and transmits in real time information about two temperature values, flow values and calculated calories for temperature difference measurement. The developed board will be useful for real - time monitoring of the state of the valve in the future and development of the valve for the offshore.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.896-899
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• 2016

Server management and power management are important to operate a data center stably and efficiently. By this paper, we introduce an web based application that is able to monitor and visualize energy consumption, help to energy consumption analysis of a data center due to provide server monitoring information such as temperatures for server, status of each device, power status using server management interfaces and power management modules in data center, also suggest the methods to implement them. This application takes advantage of IPMI which is server management standard interfaces and server management technology in manufacturer's individual way so it can do integrated monitoring for heterogeneous severs, and there is little monitoring load inside of server system because it doesn't need to install agent program for monitoring target system, and it can be used successfully to energy consumption analysis, server management in a data center due to realtime provided energy consumption and monitoring information.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.6 no.1
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• pp.29-35
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• 2010

Long-term temperature monitoring has been performed for ground heat exchanger at the Earthquake Research Center (ERC) building in Korea Institute of Geoscience and Mineral Resources (KIGAM). For the 3 years of monitoring, overall temperature increases are observed at various depths within a borehole heat exchanger. But monitoring of ground temperature variation at the monitoring well beforehand showed that geothermal utilization is not the only source for the temperature increase, Because various kinds of sources can cause the ground temperature change, more thorough investigation should be followed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.7
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• pp.765-767
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• 2016

Building Energy commissioning is a process in which verifying and making the document during entire lifetime including planning, design, construction, test run of equipment, and maintenance to minimize the operational problems of building energy efficiency. The general commissioning is replacing the equipment or reconstructing the skin to achieve the performance for the design. This process is expensive and has the disadvantage of taking a long payback period by one operation. In this paper, we studied the monitoring-based commissioning (MBCx) to increase the energy efficiency of buildings through analyzing energy use data. MBCx is modeling a building energy, comparing the real energy use with it, detecting the cause of falling the efficiency, and running the optimal operation regularly.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5C
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• pp.403-409
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• 2012

This paper proposes an energy efficient ECG monitoring system by putting some intelligence on the sensor node to reduce the number of transmissions. The sensor node is mostly put into the processing mode and just connects the base station when necessary. Therefore, the transmission energy is greatly reduced while the energy for processing is increased a little bit. Our proposed ECG analysis method classifies ECG cycles by computing the Euclidean distance between the sensed ECG cycle and the reference ECG cycle. This work is a detailed and full explanation of our former work. Extended experimental results show that the proposed trade is very effective in saving energy and the Euclidean distance based classification method is accurate. Furthermore, the PowerTOSSIM energy simulation method is also demonstrated as very accurate in evaluating the energy consumption of the sensor node in our application scenario.

• Journal of Korea Multimedia Society
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• v.22 no.11
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• pp.1324-1337
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• 2019

This study set out to investigate an energy harvesting device to ensure stable energy supply to batteries and data collection devices and a monitoring system for acer pictum sap to check collected data. Acer pictum sap farmers have written down weather information and yield of acer pictum sap manually for data storage. Since the job is done manually, there are many missing values in their data. In addition, it is not easy to manage batteries due to the characteristics of the areas where acer pictum sap is collected. The present study thus decided to build an energy harvesting device based on new renewable energy to ensure stable energy supply by taking into consideration power load, daily power consumption, and number of days with no sunshine for various devices. For a monitoring system, the investigator proposed a JSP-based web page to monitor temperature, humidity, volume of collected water, and battery state in real time. The proposed energy harvesting device was applied to reduce missing values in data. It promoted stable energy supply to the batteries and data collection devices, reducing the percentage of missing values in data from 30.55% to 0%.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.10
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• pp.69-74
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• 2014

With the increasing interest of energy efficiency, several buildings and factories begin to monitor energy usages with a built-in energy management system. However, the built-in energy monitoring system does not reflect the dynamics of buildings and factories energy usage. To overcome the latter, we deploy several sensors to monitor the dynamics of buildings energy usage patterns. In this paper, we are proposing a framework of a sensor based energy monitoring system. Based on our limited experiments, we can monitor power usages by a person, device and time period. As a result, we can plan a better energy usage and improve energy efficiency by the monitored energy usage profile data.