• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.36 no.3
• /
• pp.169-176
• /
• 2020

The authors developed a nodal network model that simulates the flow of moist air and the thermal behavior of a target area. The nodal network model was enhanced using a parameter estimation technique based on the measured temperature, humidity, and schedule data. However, the nodal model is not good enough for predicting humidity of the target space, having 55.6% of CVRMSE. It is because re-evaporation effect could not be modeled due to uncertain factors in the field measurement. Hence, a data-driven model was introduced using an artificial neural network (ANN). It was found that the data-driven model is suitable for predicting the condensation compared to the nodal model satisfying ASHRAE Guideline with 3.36% of CVRMSE for temprature, relative humidity, and surface temperature on average. The model will be embedded in automated devices for real-time predictive control, to minimize the risk of surface condensation at dressroom in an apartment housing.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.9
• /
• pp.1985-1988
• /
• 2009

Poly (lactic-co-glycolic acid) (PLGA) nanoparticles loading paclitaxel have been deposited on coronary stents by self-assembling properties of colloidal particles. The layers of the nanoparticles were enhanced to a sufficient mechanical strength by a thermal process under the proper temperature and humidity conditions. In vitro release studies proved the controlled paclitaxel release of the nanoparticle layers. This technique gives rise to a new range of applications for nanoparticles and drug-eluting stents.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2011.05a
• /
• pp.48.1-48.1
• /
• 2011

In this presentation, We monitored weather data, such as global irradiance, ambient temperature, temperature of PV module, relative humidity and windspeed for 2 years, for determining accelerated test condition. then, we determined the temperature limit of accelerated test through weather data and FEM analysis. Detailed procedures will be summarized in this work. After analysing outdoor stress such as thermal stress, we decided main failure modes and mechanisms of PV module, especially solder joint of ribbon wire. we carried out the measurement of material properties such as thermal expansion coefficient for planning of accelerated test. we designed accelerated test based on FEM analysis results. we carried out thermal cycling test with 1 cell mini module for 3 months. We monitored the change of electrical performance every 1 week such as Voc, Isc, Pmax, etc. and then, we analized the ribbon wire/electrode intefaces. Detailed results will be summarized in this work.

• Journal of the Korean housing association
• /
• v.10 no.4
• /
• pp.111-120
• /
• 1999

The purpose of this study is to evaluate the efficiency of the thermal environment created by the cooling system at the apartment that combines the forced convection cooling(the system reducing humidity from room) with the floor cooling radiation which uses the floor panel from floor heating system, a general residential heating system in Korea. In this study, the combined cooling system in which air supply, spurt temperature difference and interior draft are reduced, is compared with the existing forced convection cooling system. To identify the effect of the comparison concretely, a comparative experiment is carried out on tour conditions, ie, convection cooling, floor radiation convection cooling and floor radiation cooling. Through it the characteristical thermal environment formed within the model room is analyzed, and the conveying system of compressed floor chill and condensation problem are reviewed.

• 유체기계공업학회:학술대회논문집
• /
• 2006.08a
• /
• pp.487-488
• /
• 2006

In these days, demand of a LCD monitor is remarkably increasing with development of the LCD technology. However, there are thermal problems for improvement of efficiency for the LCD monitor. Thus, this research analyzed thermal problems such as convection and conduction heat transfer characteristics in the LCD monitor using an infrared (IR) camera. Also, the results of the outer side of the front LCD panel using the IR camera have been compared with the results of the inner side of the front panel using T-type thermocouples. The equations have been derived for the temperature distribution of the inner side of the front LCD panel by a multiple regression method including variables for ambient temperature, humidity and temperature differences between the front and back panels of the LCD monitor.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
• /
• 1998.11a
• /
• pp.88-93
• /
• 1998

The purpose of this study was to examine theory about indoor thermal comfort-environment as well as to determine thermal sensation and physical responses for men in summer and winter indoor environment, under various air temperature and relative humidity, with male university students. Subjective Evaluation, Heart rate(Electrocardiogram, ECG), Electroencephalo gram(EEG) were examined. We found that comfort of people was achieved at SET*. 24.7$^{\circ}C$, -0.82${\alpha}$-wave) both in summer and in winter.

• Proceedings of the SAREK Conference
• /
• 2007.11a
• /
• pp.76-81
• /
• 2007

The shopping center in underground passage increased for efficient space utilization in urban area. This study describes operation characteristics of all air type and hybrid type with local ventilation and fan coil unit fixed to ceiling. In order to compare energy saving, thermal environment and installation space, etc., integrated simulator with heat production and indoor distribution system is designed and constructed. Energy saving of the hybrid system is calculated as over 30% compared to conventional all air type. And also the results showed that humidity decreased about 6%, also indoor thermal distribution is improved as temperature variation of around $1^{\circ}C$.

• Journal of the Korean Institute of Educational Facilities
• /
• v.6 no.4
• /
• pp.16-23
• /
• 1999

The thermal and condensation performance of steel stud walls are monitored in steel-framed schools of Ee-Wol Elementary School and kindergarten using temperature and humidity sensors installed. The monitoring process carried out during the summer and winter period, shows decrement effect of the external heat flow to be quite remarkable and excellent. And steel stud walls provides a highly efficient time-lag effect in spite of its light weight property, with 30 minutes to 4 hours time-lag for external heat flow, which variation mainly depends on its location of each part of the wall. Any condensation phenomena are not observed in either external or internal surfaces.

• Steel and Composite Structures
• /
• v.31 no.6
• /
• pp.641-653
• /
• 2019

In this paper, wave propagation is studied and analyzed in double-layered nanotubes systems via the nonlocal strain gradient theory. To the author's knowledge, the present paper is the first to investigate the wave propagation characteristics of double-layered porous nanotubes systems. It is generally considered that the material properties of nanotubes are related to the porosity and hygro-thermal effects. The governing equations of the double-layered nanotubes systems are derived by using the Hamilton principle. The dispersion relations and displacement fields of wave propagation in the double nanotubes systems which experience three different types of motion are obtained and discussed. The results show that the phase velocities of the double nanotubes systems depend on porosity, humidity change, temperature change, material composition, non-local parameter, strain gradient parameter, interlayer spring, and wave number.

• Proceeding of Spring/Autumn Annual Conference of KHA
• /
• 2006.11a
• /
• pp.291-296
• /
• 2006

The purpose of this study were to make clear the present condition of indoor thermal and air environment by air-conditioning in school classrooms and to analyze the relation of the living conditions with indoor environment. The measurements on physical elements and observations on living conditions were carried out in 6 classrooms of 3 middle or high schools. Measuring elements were indoor temperature, relative humidity, $PM_{10}$ and $CO_2$ concentration. As results, the averages of indoor temperature each classrooms were 24.9${\sim}$26.6 . Most of classrooms were lower than the Maintenance standard(26${\sim}$28 ) of School Health Law. The means of relative humidity were 51.3${\sim}$72%, all classrooms were ranged within the standard(30${\sim}$80%). The means of $PM_{10}$ concentration were 3.5${\sim}$23.1 ${\mu}g/m^3$, all classrooms were kept within the standard(100 ${\mu}g/m^3$). The means of $CO_2$ concentration were 1218.7${\sim}$4705.4 ppm, all classrooms were exceed the standard(1,000ppm). The results of analysis on relations of living conditions with the physical elements are as follow; the air conditioner set of temperature, windows and doors opening elapsed time, the number of students in classrooms and activities of students had certain effect on indoor environment.