• Korean Journal of Construction Engineering and Management
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• v.11 no.6
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• pp.65-77
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• 2010

Our nation's housing construction is given much weight over 32% in 2007 and especially apartment is taking over 67%. If we put into construction environment consideration, we are having a trouble with price cap policy and the realestate recession due to the global economic crisis. So in order to get competitive power and supply of cheap apartment, the necessity of cost saving is increasing. This research collected the past constructed apartment project's cost saving examples which were influencing on the construction cost, quality and time. We analyzed collected cost saving datum and assorted these in compliance with classification system. By analysis of correlation among datum with exclusion and integration, we make a propose cost saving Checklist that will be a base data to give a chance to use in working level and other research.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.1
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• pp.58-66
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• 2013

Most of steam power plant in Korea are heating the feed water system to prevent freezing water flowing in the pipe in winter time. The heating system is operated whenever the ambient temperature around the power plant area below 5 degree Centigrade. But this kind of heat supplying system cause a lot of energy consuming. If we think about the method that the temperature of the each pipe is controled by attaching the temperature measuring sensor like RTD sensor and heat is supplied only when the outer surface temperature of the pipe is under 5 degree Centigrade, then we can save a plenty of energy. In this study, the computer program package for simulation is used to compare the energy consumption load of both systems. Energy saving rate is calculated for the location of Youngweol area using the data of weather station in winter season, especially the January' severe weather data is analyzed for comparison. Various convection heat transfer coefficients for the ambient air and the flowing water inside the pipe was used for the accurate calculation. And also the various initial flowing water temperature was used for the system. Steady state analysis is done previously to approximate the result before the simulation. The result shows that the temperature control system using RTD sensor represents the high energy saving effect which is more than 90% of energy saving rate. Even in the severe January weather condition, the energy saving rate is almost 60%.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5B
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• pp.317-326
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• 2012

Recently, many researchers have studied to solve the energy consumption of network equipments since the interest of Green IT has been increased. In this paper, we apply Low Power Idle (LPI) to OBS network to reduce energy consumption of network devices. Many previous researches have focused on maximizing the sleep time of network equipments to increase the energy saving efficiency of LPI. But transition overhead caused by LPI might not only depreciate the performance of energy saving but also increase packet delay. In this paper, Transition Decision (TD) algorithm is proposed to improve energy saving efficiency by reducing the number of unnecessary transition and guarantee the required QoS such as packet delay. To evaluate the performance of proposed algorithm, we model OBS edge router with LPI by OPNET and analyze the performance of the proposed algorithm in views of energy saving, transition count and average packet delay.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.154-159
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• 2008

Daylight is an important component for human and energy saving. Also, available daylight in inside provides positive influence on psychological and physiological aspects as well as good visual environment. It is important to lighting design for office building not only designing for artificial lighting but also using daylight for energy savings. Therefore, lighting designers and architectures must consider the effects of the daylight for human environment and energy savings. The BIN Method is one of the methods to predict energy savings using computer simulation but it spends more time than expectation. So, this study performs to simulate a simple space using the RADIANCE for examination and simplification of the BIN Method.

• Journal of the Korea Society of Computer and Information
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• v.21 no.7
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• pp.39-46
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• 2016

In this paper, we proposed an application which can conduct to take repetition images for special effect shooting at movies or drama using Bluetooth of smart device. The proposed application can move a camera with motors several times as the same moving after saving of the control data based on the application during specific time using Bluetooth. At the repetition moving, we do not permit to control motors of the camera by person for keeping the same start position and end position after saving the moving data. The camera motors are only moved remotely by saving data of the proposed application. We developed the proposed application and a hardware which works motors with camera to check performance evaluation. Then, we confirmed that the proposed application exactly did the same moving to the motors with camera several times according to saved data. Therefore, because the proposed application can take a same images as control remotely the motors of camera, it will be a useful technology for special effect shooting of movies or dramas.

• Journal of the Korea Computer Industry Society
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• v.6 no.5
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• pp.741-748
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• 2005

Power saving module which is consisted of ferroelectric ceramic capacitor and time delay switching circuit was installed into electronic ballast in order to enhance energy efficacy and extend life time of fluorescent lamp. The impedance matching of negative resistance characteristics of F/L was optimized with the characteristics of ferroelectric ceramics capacitor to increase the light efficiency of the electronic ballast. The high efficiency of the electronic ballast was achieved by minimizing wasted power at the filament of F/L during the lighting by using the switching function of time delay circuit from preheating mode to non-preheating mode. The life time of F/L was also extended by eliminating the reverse electromotive force using time delay circuits to minimize the impacts to the filament of F/L from unwanted high voltage peaks during light-up period. As the results, the electronic ballast with the first grade energy efficiency was developed using ferroelectric ceramics and time delay module.

• International Journal of High-Rise Buildings
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• v.2 no.4
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• pp.331-340
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• 2013

The main topic of this paper is to show a possibility of indoor air quality enhancement and the fan energy savings in underground parking facilities by applying the demand-controlled ventilation (DCV) strategy based on the real-time variation of the traffic load. The established ventilation rate is estimated by considering the passing distance, CO emission rate, idling time of a vehicle, and the floor area of the parking facility. However, they are hard to be integrated into the real-time DCV control. As a solution to this problem, the minimum ventilation rate per a single vehicle is derived in this research based on the actual ventilation data acquired from several existing underground parking facilities. And then its applicability to the DCV based on the real-time variation of the traffic load is verified by simulating the real-time carbon monoxide concentration variation. The energy saving potentials of the proposed DCV strategy is also checked by comparing it with those for the current underground parking facility ventilation systems found in the open literature.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.10
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• pp.161-167
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• 2015

This paper presented an occupancy-based energy saving system for appliance energy saving in smart house. The developed system is composed of a sensing system and a home gateway system. The sensing system is set of wireless sensor nodes which have pyroelectric infrared (PIR) sensor to detect a motion of human and set of smart plugs which measure the current using CT (current transformer) sensor and send the current to home gateway wirelessly. We measured current consumption of appliances in real time using smart plugs, and checked the occupation of residents using occupancy sensors installed on the door and room. The proposed system saves electric energy to switch off the supply power of unnecessary usages in the unoccupied spaces. Experiments conducted have shown that electric energy usage of appliances can be saved about 34% checked by using occupation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.1
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• pp.67-74
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• 2014

Most of steam power plants in Korea are using the method of heating the feed water whenever the ambient temperature around the power plant area below $5^{\circ}C$ to prevent freezing water flowing in the pipe in winter time. But this kind of heat supplying system is not useful to save energy. If we take the method that the temperature of the each pipe is controled by direct measure of temperature by attaching sensor on the outside surface of the feed water tubes, then we can expect that a plenty of energy can be saved. In this study, the computer simulation is used to compare the energy consumption loads of both systems. Energy saving rate is calculated for the location of Incheon area in winter season. Four convection heat transfer coefficients for the ambient air and three initial flowing water temperature inside the tube were used. The result shows that the temperature control system using sensor represents more than 95% of energy saving rate in Incheon area. Even in the severe January weather condition, the energy saving rate is almost 75% in two days basis and even 83% in one day basis.

• Journal of Korean Institute of Fire Investigation
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• v.11 no.1
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• pp.66-73
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• 2008

In this research, the electric power consumptions of the electrical machinery and appliances selected in the Seoul division of Korea Electrical Safety Corporation were measured. The power-saving efficiency was investigated by comparing the amounts of the reserved electric power when the Saver was on or off through measuring that of the reserved electric power before and after equipping the selected appliances with the Saver, a cutoff of the reserved electric power. As a result, the power-saving efficiency was around 18% when the Saver was installed. It can be ascribed to the removal of the source wasting electrical energy. Furthermore, by blocking the reserved electric power, the electric fire can be originally prevented and also the life time of the electrical machinery and appliances can be postponed.