• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.110-110
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• 2017

• Journal of the Korea Safety Management & Science
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• v.16 no.2
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• pp.167-174
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• 2014

Heating and air conditioning system is changing rapidly from the traditional HVAC central supply system to the individual supply system with electrical heat pump system (EHP) in Korean school buildings. The individual supply system has advantages to turn on and off individually and to adjust the thermal comfort separately, but energy is wasted in the unoccupied classroom when the last leaving occupant does not turn off the controller. If the controller is to be off automatically while the classroom is not in use, energy consumption would decrease dramatically. This project aims to cease the unnecessary EHP supply in vacant classroom by inputting the class schedule from the central control room to reduce the energy-spending. Experimental measurements were carried out between the controlled classroom that is turned off when not in use and the uncontrolled room that is turned on continually. Occupant's comfort and energy consumption were measured and compared between the controlled case and the uncontrolled case. The energy consumption of controlled classroom case is 30-60% less than that of the uncontrolled classroom case. This result shows that controlling the cooling supply for the unoccupied classroom using the class schedule can decrease the energy consumption remarkably. This supply control system can be used to conserve energy in school structures like universities.

• Journal of the Korea Safety Management & Science
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• v.15 no.1
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• pp.161-167
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• 2013

The purpose of this study was to assess power loss in the computer and office automation equipment and identified a way to save power consumptions through field measurement. In this study, the meaning of standby power was to consume power while waiting for the use of any electronic equipment. This standby consumption was about 11% of total power consumption even though we did not seriously realize it. Therefore, it was very important to measure accurate power consumption at the standby status of electronic equipment. In addition, it also helped to reduce potential risks of electricity associated disasters. This study proposed the way to reduce power losses through automatic turn off switches for power outlets and switches. Finally, this study can evaluate power consumption patterns that can reduce power consumptions and potential risks of power related disasters. This also can achieve the goals of sustainability that can reduce environmental impacts by lowering energy consumptions and greenhouse gas emissions.

• Journal of the Korea Safety Management & Science
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• v.14 no.4
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• pp.147-152
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• 2012

Supply chain including transportation expend the 21% of domestic energy consumption. It is necessary to diminish the excess energy usage at entire supply chain. This paper deals with the application of MFCA(Material Flow Cost Accounting) for SCM to save energy consumption. We construct the material center corresponding to each logistics function in order to apply the MFCA for GCM(Green Chain Management). We also construct the MFCA framework which consists of MFCA Database Management, MFCA Visualization, GCM Data Integration, GCM Data Tracking, and MFCA Data Predict & Assignment. We expect to help determining the range of logistics function to apply the MFCA for GCM.

• Journal of the Korea Safety Management & Science
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• v.13 no.2
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• pp.147-155
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• 2011

For an effective energy management in intelligent buildings it is necessary to gather information about position/absence of people and the level of population. In this paper the smart occupancy detection system based on the active RFID is developed to satisfy such a demand. The performance of the developed system is tested and verified through various experiments. Furthermore the feasibility test of the active RFID tag is performed to verify whether it can be used as a location-based occupancy sensor. The developed core technology can be also applied to other fields such as security, healthcare, smart home, etc.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.171-176
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• 2010

Railway has recently played an important role in preventing global warming caused by green house gases and furthering a low carbon green growth, The various railway research centers have conducted facilitated studies on saving energy. In particular, urban railway has emerged as the best means of public transportation in terms of punctuality, safety and environmentally friendliness. There are various ways to save energy in terms of operation of urban railway system, and they can be generally divided into hardware aspects that pertain to structure of vehicles and development of control system and software aspects that pertain to effective operation of trains based on operation patterns and diagram control. In this paper, we investigated drive assistance system for railway energy efficiency. The railway operation patterns and train diagram management programs were researched.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1345-1347
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• 2000

This paper presents a new method to reducing inrush current and energy saving of capacitor starting single-phase induction motor used in air-conditioner. It can be obtained that proposed system is low cost and small size as compared with other controller. Experiments are focused on a capacitor starting single-phase induction motor. The optimal power saving and in-rush current limiting by phase angle control are verified by experimental results. Also, auxiliary winding was controlled by electronic starting switch.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.1
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• pp.51-58
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• 2001

The use of tailor welded blanks (TWB) in automotive applications is increasing due to the potential of weight and cost saving. The object of this study is development of the front side member by static analysis and crash simulations. Accord-ing to the results , energy absorption and barrier force is very important parameter to control passenger safety and deforma-tion shape. A energy absorbability point of view, tailor welded blanks is most effective to absorb energy than non-twb. Non-TWB front side member and TWB applied front side member were simulated. It shows reduce stmping parts weight reduction and cost down.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.210-216
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• 1998

The most important thing to consider in cold store design are to save cooling energy consumption and to keep goods freshly. Specially there are many efforts to save energy with cold store in Korea. A building energy simulation program should be used to optimally select a cooling system to match the criteria of cooling rate and storage rate in a given cool crop storage building and HVAC system. The low maintenance costs, high degree of safety and environmental impacts are also favouring the underground solution. There are obviously a lot of possibility for cost-effective storage of cooled or frozen goods or liquids in ground water rock.

• International Journal of Fluid Machinery and Systems
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• v.6 no.3
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• pp.160-169
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• 2013

Two-stage turbocharging is an important way to raise engine power density, to realize energy saving and emission reducing. At present, turbine matching of two-stage turbocharger is based on MAP of turbine. The matching method does not take the effect of turbines' interaction into consideration, assuming that flow at high pressure turbine outlet and low pressure turbine inlet is uniform. Actually, there is swirl flow at outlet of high pressure turbine, and the swirl flow will influence performance of low pressure turbine which influencing performance of engine further. Three-dimension models of turbines with two-stage turbocharger were built in this paper. Based on the turbine models, mechanism of swirl flow at high pressure turbine outlet influencing low pressure turbine performance was studied and a two-stage radial counter-rotation turbine system was raised. Mechanisms of the influence of counter-rotation turbine system acting on low-pressure turbine were studied using simulation method. The research result proved that in condition of small turbine flow rate corresponding to engine low-speed working condition, counter-rotation turbine system can effectively decrease the influence of swirl flow at high pressure turbine outlet imposing on low pressure turbine and increases efficiency of the low-pressure turbine, furthermore increases the low-speed performance of the engine.