• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1997.04a
• /
• pp.452-459
• /
• 1997

For computer aided design and construction of low noisy power plants, indoor and outdoor noise prediction program has been developed. The program utilizes the predefined data of noise sources and building materials and has the faculty to estimate the source level using the empirical formula in case of the measured data not being available. In the noise prediction, the mutual noise propagation between indoor and outdoor sites are considered. The outdoor noise source in the calculation of geometric divergence effects is modelled as the omni-directional finite line or planar source according to the source geometry and the receiving points. Outdoor noise prediction is carried out to consider the diffraction effect due to plant structures as well as the attenuation effect due to atmospheric absorption and soft ground. The results of indoor and outdoor noise prediction for a recently constructed diesel engine power plant show good agreement with the measured.

• KIEAE Journal
• /
• v.16 no.2
• /
• pp.5-10
• /
• 2016

Purpose: Recently, many public office buildings which were built by curtain wall increased rapidly, but the results of the investigation of the government, these buildings have been found that the heating and cooling thermal load is high, and showed low energy efficiency. Method: To evaluate the effects by applying outdoor louver and indoor blind, which can control solar radiation in order to reduce the heating and cooling load of public office building which was built by glass curtain wall. The heating and cooling load was calculated via Energyplus, building and outdoor louver, indoor blind were modeled by Google sketchup connected to Energyplus. Result: The results of this study were as follows; the case of applying various outdoor louver, the heating and cooling load all decreased as compared to the case without applying outdoor louver, the case of applying indoor blind, the heating and cooling load decreased as compared to the case without applying indoor blind, but indoor blind showed low energy performance comparing outdoor louver.

• Proceedings of the SAREK Conference
• /
• 2008.06a
• /
• pp.591-596
• /
• 2008

The present study has been conducted to study the performance of dedicated outdoor air handling unit in central and personal air-conditioning. With conventional central and personal air-conditioning systems which are designed according to the maximum load, humidity increase above comfort level can not be avoided as the cooling load decreases. The adoption of dedicated outdoor air handling unit, however, can solve this problem. Moreover, the dedicated outdoor air handling unit has the characteristics of anti-bacteria due to dry coil, energy saving and good indoor air quality. During cooling seasons, dedicated outdoor air handling unit can save energy up to 30% than the conventional cooling+reheating system for controlling both temperature and humidity.

• The Journal of Korea Robotics Society
• /
• v.6 no.3
• /
• pp.292-300
• /
• 2011

Global positioning system (GPS) is widely used to measure the position of a vehicle. However, the accuracy of the GPS can be severely affected by surrounding environmental conditions. To deal with this problem, the GPS and odometry data can be combined using an extended Kalman filter. For stable navigation of an outdoor mobile robot using the GPS, this paper proposes two methods to evaluate the reliability of the GPS data. The first method is to calculate the standard deviation of the GPS data and reflect it to deal with the uncertainty of the GPS data. The second method is to match the GPS data to the traversability map which can be obtained by classifying outdoor terrain data. By matching of the GPS data with the traversability map, we can determine whether to use the GPS data or not. The experimental results show that the proposed methods can enhance the performance of the GPS-based outdoor localization.

• KIEAE Journal
• /
• v.3 no.3
• /
• pp.3-11
• /
• 2003

The purpose of this study is to develope an available outdoor insulation construction for the green roof system in Korea. On its own economical and structural problems of constructional risk, the typical outdoor insulation construction on the korean spot does not function efficiently with the green roof. Therefore, this study consists of four main contents as follows: 1. The objectives of the study are established by analysing the problems of the typical in- and outdoor roof insulation system in korea. 2. The foreign outdoor insulation systems for the green roof are clarified to find out an acceptable prototype for Korea. 3. According to loadtest, the prototype, which has a waterproof on the thermal insulation, is tested to demonstrate the structural safety. 4. The U-value test of the prototype on KS F 2277 brings the thermal performance of the green roof system, which can influence the thickness of the insulation.

• Proceedings of the KSME Conference
• /
• 2008.11b
• /
• pp.2322-2327
• /
• 2008

This paper is to provide analysis model that can be used to investigate the improvement in energy efficiency for cooling tower by using fresh air. Numerical analysis of Air-cooled heat exchanger for single-phase flow with variations of outdoor air temperature has been performed. A complete set of correlations of the heat transfer in both refrigerant and air sides was employed for predicting the heat transfer rate. The numerical results derived from the correlations were verified with experimental results. The energy consumption for a hybrid cooling tower has been compared for variation of a outdoor air temperature. The results showed that the hybrid cooling tower in low outdoor temperature offers a significant improvement in energy efficiency. The thermal analysis aids significantly in the solution of the design problem of hybrid cooling tower.

• 한국태양에너지학회:학술대회논문집
• /
• 2009.11a
• /
• pp.38-43
• /
• 2009

Since most of the existing CFD simulation about thermal environment was limited as indoor environment, it is not appropriate to adopt the same method for external thermal environment, because the solar radiation highly affect the outdoor thermal environment. Thus, in case of assessing the outdoor thermal environment, the radiation calculation is very important. In this study, as a new method to evaluate the outdoor thermal environment, coupled simulation of convection and radiation will be proposed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.05a
• /
• pp.23-28
• /
• 2000

Insulator systems using resin casting apparatus are useful to realize the high capacity, small size, and combined electric power equipments, and are expected to bring various advantages. In Korea, epoxy resin molded apparatus have been restricted to indoor uses till now. On the other hand, in Europe, molded insulators and transformers and so forth have been practically used since the former half of 1960's. Recently, investigation on epoxy resin materials and molded apparatus for outdoor use have ben intensively carried out. Probably, this is because electric power outdoor apparatus such as distribution transformer can be given multi-functions by using outdoor epoxy resin compound This study describes the trend on the development of epoxy mold transformers, and important technologies applied for outdoor use.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.14 no.7
• /
• pp.577-585
• /
• 2004

In this paper, reactive shearing structural intensity method is extended to damping patches placement on outer panels of outdoor unit of air-conditioner to reduce its structural borne noise. The structural intensity is calculated from the normal velocities of structures that are measured by using a laser scanning vibrometer, and $textsc{k}$-space (wave-number domain) signal processing is used to obtain the spatial derivatives in formulation of structural intensity. This method is applied to the outdoor unit of air-conditioner on shaker-exciting mode and operating mode. and then damping patches are placed over area of high reactive shearing structural intensity for reducing the radiated noise. Experimental results show the largest reduction of sound pressure level of an outdoor unit by appling small damping patches to optimal position.

• Hwankyungkyoyuk
• /
• v.24 no.3
• /
• pp.44-55
• /
• 2011

This study examined the effects of RSM (Regional Science education resource Map), developed and provided by Busan metropolitan city Office of Education, at high schools in Busan. Two group of students, who were in the same level of achievement as well as other environmental conditions, participated in this study. Twenty nine of students as an experimental group experienced outdoor activities utilizing RSM, while thirty of students as a control group did not participate in any outdoor activities. The results indicated that compared to the control group of students, the experimental group of students represented a significant improvement in students' environmental attitudes, local ecological interest and eco-friendly behavior. The teachers who guided outdoor activities utilizing RSM suggested that RSM needs to be further subdivided by seasons as well as local districts. They also suggested that RSM needs to be linked with a school curriculum.