• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.4
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• pp.175-184
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• 2017

With the improvement of living standards, the ventilation for the mitigation of indoor or outdoor air-pollution problems has recently attracted a lot of attention. Consequently, the ventilation for the supply of outdoor fresh air into a room is treated as an important building-design factor. The ventilation is generally divided into the forced and natural types; here, the former can control the ventilation rate by using mechanical devices, but it has the disadvantages of the equipment costs, maintenance costs, and noise generation, while the latter is applied to most workshops due to the absence of noise and the low installation and maintenance costs. In this experimental study, the ventilation performance of a typical rotating-type natural ventilator, which is called a "wind turbine," was investigated with the outdoor-wind velocity and the indoor/outdoor-temperature difference. From the experiment results, it was confirmed that the temperature difference of $10^{\circ}C$ corresponds to the ventilation driving force with an outdoor-wind velocity of 1.0 m/s. Additionally, the intake-opening area of a building also exerts a great effect on the ventilation rates.

• Journal of Bio-Environment Control
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• v.23 no.3
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• pp.174-180
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• 2014

Standard weather data available to greenhouse environmental design are limited in most regions of the country. So, instead of using standard weather data, in order to find the method to build design weather data for greenhouse heating and cooling, design outdoor weather conditions were analyzed and compared by TAC method and frequency analysis using climatological normal and thirty years from 1981 to 2010 hourly weather data provided by KMA and standard weather data provided by KSES. Average TAC values of outdoor temperature, relative humidity and insolation using thirty years hourly weather data showed a good agreement with them using standard weather data. Therefore, in regions which are not available standard weather data, we suggest that design outdoor weather conditions should be analyzed using thirty years hourly weather data. Average of TAC values derived from every year hourly weather data during the whole period can be established as environmental design standards, and also minimum and maximum of them can be used as reference data.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.107-109
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• 2014

Through the economic development, people enjoying the camping and demand of camping goods are increasing since they have free time. So they use portable butane gas range outdoor. In addition to that, many restaurants that offer hotpot or meat in Korea use portable butane gas ranges for their convenience. But 19% of gas accidents are using portable butane gas range, 13.7% of them are using oversized cookware. Despite the high accident rate, there is no safety standards about portable butane gas range using oversized cookware. Therefore we conducted to measure temperature and pressure of portable butane gas ranges for reforming safety standards. As a result. we confirmed relation between bottom temperature of the portable butane gas barrel and pressure of the butane gas. Also we confirmed that portable butane gas ranges operate safely when bottom temperature of the portable butane gas barrel is bellow $50^{\circ}C$.

• Journal of Environmental Health Sciences
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• v.48 no.6
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• pp.291-297
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• 2022

Background: PM_2.5 and black carbon (BC) can be generated from cooking and from vehicle operation. Street vendors may be exposed to PM_2.5 and BC due to their proximity both to roads and to cooking activities. Objectives: The objectives of this study were to evaluate the PM_2.5 and BC concentrations in cooking stalls and to determine the effects of cooking activity and of types of cooking. Methods: Indoor and outdoor PM_2.5 and BC concentrations, temperature, and relative humidity were measured in 32 stalls in April and May 2022. Behavioral factors such as the presence of cooking activity and types of cooking were observed. Student's T-test was performed using the difference of indoor and outdoor PM_2.5 and BC concentrations to compare the effects of cooking activity and to compare types of cooking. Results: One-hour averages of the difference in indoor and outdoor PM_2.5 concentrations for cooking stalls and non-cooking stalls were 9.7±15.7 ㎍/m³ (n=22) and -0.5±0.4 ㎍/m³ (n=10), respectively. The difference in indoor and outdoor PM_2.5 concentrations in cooking stalls was significantly higher than in non-cooking stalls (p<0.05). The indoor PM_2.5 concentration for stalls for Chinese pancakes and teokbokki exceeded the standards for indoor air quality in South Korea (50 ㎍/m³ ). The indoor PM_2.5 concentration for Korean pancake stalls exceeded the standards for outdoor air quality in South Korea (35 ㎍/m³ for 24 hours). Conclusions: The PM_2.5 concentrations in stalls with cooking activity was significantly higher than those in stalls without cooking activity. Some stalls with certain types of foods exceeded standards for indoor and outdoor air quality in South Korea. Better management of indoor air quality in stalls with cooking activities is necessary.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.269-275
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• 2018

In order to establish the criterion for analyzing outdoor weather conditions in the greenhouse heating and cooling system design, we analyzed heating and cooling design outdoor temperatures by the annual percentile method and compared with design outdoor temperatures by the existing seasonal percentile method. In the annual percentile method, 0.4%, 1% and 2% of the total 8,760 hours per year are presented as cooling design outdoor temperatures and 99.6% and 99% as heating design outdoor temperatures. When the annual percentile method was adopted, heating design outdoor temperatures increased by 6.7 to 9.6% compared with the seasonal percentile method, and cooling design outdoor temperatures decreased by 0.6 to 1.1%. The maximum heating load in the same greenhouse condition decreased by 3.0 to 3.6% when the annual percentile method was adopted, but the effect on the maximum cooling load was insignificant. Therefore, it is necessary to consider the change of heating design outdoor temperatures to the annual percentile method, but it is not necessary to change the cooling design outdoor temperatures since there is little difference between the two methods.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.308-319
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• 2016

In order to set the outdoor weather conditions to be applied to the design standard of the greenhouse heating and cooling system, outdoor air temperature and heating degree-hour for heating design, dry bulb temperature, wet bulb temperature and solar irradiance for cooling design were analyzed and presented. For every region in Korea, we used thirty years from 1981 to 2010 hourly weather data for analysis, which is the current standard of climatological normal provided by KMA. Since the use of standard weather data is limited, design weather conditions were obtained using the entire weather data for 30 years, and the average value of the entire data period was presented as a design standard. The design weather data with exceedance probability of 1, 2.5, and 5% were analyzed by the TAC method, and we presented the distribution map with exceedance probability of 1% for heating and 2.5% for cooling which are recommended by design standards. The changes of maximum heating load, seasonal heating load and maximum cooling load were examined by regions, exceedance probabilities, and setpoint temperatures. The proposed outdoor design conditions can be used not only directly for the greenhouse heating and cooling design, but also for the reinforcement of heating and cooling facilities and the establishment of energy saving measures. Recently, due to the climate change, sweltering heat in summer and abnormal temperature in winter are occurring frequently, so we need to analyze weather data periodically and revise the design standard at least every 10 years cycle.

• Land and Housing Review
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• v.2 no.3
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• pp.269-276
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• 2011

Recently, the chance of dew condensation in apartment buildings is increasing because of several reasons. For example, ventilation rate has been decreased because of high-insulations and airtightness for saving energy. Besides, the humidity has been made by drying washes, cooking and bathing inside of apartment buildings. However, there is lack of resonable design criteria for preventing condensation in real life and real surroundings. Therefore, this study is aimed at making a resonable design criteria of preventing condensation by measuring the indoor temperature and humidity in real life. In addition to this, it is aimed at making a resonable outdoor condition and classifying regions by using weather data. The following are the results. The interior criterion for condensation was set up $25^{\circ}C$ and a relative humidity of 55%. The outdoor criterion for condensation was set up $20^{\circ}C$, $-15^{\circ}C$, and $10^{\circ}C$ respectively for the hard frost, middle, and southern areas.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.12
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• pp.15-21
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• 2015

We proposed 50W-LED modules of using Heat-pipe and Stack-fin and produced LED modules was evaluated heat dissipation characteristics with comparison of the conventional die-casting type. It verified the application of products by applying it to 150W-LED road luminaires through simulation. The LED module was measures aimed design temperature of the Stack-fin and showed 26% upward heat dissipation effect than a conventional die-casting type. The luminous efficacy of 150W-LED road luminaires using this LED module reached over 112lm/W, and the simulation results showed average of horizontal luminance, overall luminance uniformity($U_O$) and lane luminance uniformity($U_I$) that is suitable for five-lane road with the KS standards.

• International Journal of High-Rise Buildings
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• v.3 no.2
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• pp.147-154
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• 2014

The purposes of this study were to analyze criteria for measurement chamber design dedicated curtain wall, and how to measure of performance configuration and status of the chamber that is currently being used. Main dealing criteria is AAMA 1503-09. Measurement of data is made in curtain wall Mock-up experiment station with thermal imaging camera. Measurement data using thermal imaging cameras at Mock-up curtain was made at the test site. The results of this study were as follows; There is no U-value test method for actual size of curtain wall. The thermal test outdoor chamber showed heat loss in the connection part of indoor and outdoor chamber. And the indoor chamber showed unstable temperature distribution by height.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.1
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• pp.91-100
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• 2004

Energy efficiency evaluation method for a multi-type air conditioning system still has not been developed. In this study, analysis on capacity range and evaluating method of standards for air conditioners was conducted with world-wide Standards. It is not a proper approach to use the standards for residential air conditioner to multi type air conditioners. Some difficulties and problems are commented in this study with overview of the standards. Through the analytic research, an evaluating method for multi type air conditioner was suggested with Integrated Part Load Value (IPLV). The suggested concept for evaluating energy efficiency during part load condition considers building load pattern and operating hours of the system at different locations. Load was weighted in IPLV to consider not only the concept of occurrence of outdoor temperature such as bin method but also operation hours of the system. An experiment about the IPLV was conducted with variable air volume ducted type air conditioning system and multi-type system through modified code tester to give a glance at quantitative value of the IPLV.