• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.7 no.2
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• pp.341-352
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• 1995

In this study, thermal parameters were measured and 213 occupants were also questioned in three office buildings located in Seoul during the summer season. Predicted mean vote-predicted percentage of dissatisfied(PMV-PPD) and standard new effective temperature(SET*) were used for evaluating Korean thermal sensation. The distribution of thermal sensation vote(TSV) and percentage of dissatisfied(PD) is very similar to that of PMV and PPD. By regression analysis, the following regression equation was obtained; TSV=0.339SET*-8.583. In this case, neutral temperature and comfort range are $25.3^{\circ}C$, $23.8{\sim}26.8^{\circ}C$ respectively. Present experimental results obtained from the field study is less sensitive to the temperature change than those obtained from the climate chamber study in Korea. But, thermal sensations are similar to each other near the neutral point. The neutral temperature and comfort range obtained by this experiment are higher than those of ANSI/ASHRAE Standard 55-1974 about $1.4{\sim}1.8^{\circ}C$.

• Advances in Energy Research
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• v.5 no.4
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• pp.289-304
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• 2017

Large glazed surfaces and windows become common features in modern buildings. The spread of these features was influenced by the dependence of designers on mechanical and artificial systems to provide occupants with thermal and visual comfort. Countries with hot summer and cold winter conditions, like Jordan, require maximum shading from solar radiation in summer, and maximum exposure in winter to reduce cooling and heating loads respectively. The current research aims at designing optimized double-positioned external shading device systems that help to reduce energy consumption in buildings and provide thermal and visual comfort during both hot and cold seasons. Using energy plus, a whole building energy simulation program, and radiance, Lighting Simulation Tool, with DesignBuilder interface, a series of computer simulations for energy consumption and daylighting performance were conducted for offices with south, east, or west windows. The research was based on comparison to determine the best fit characteristics for two positions of adjustable horizontal louvers on south facade or vertical fins on east and west facades for summer and winter conditions. The adjustable shading systems can be applied for new or retrofitted office or housing buildings. The optimized shading devices for summer and winter positions helped to reduce the net annual energy consumption compared to a base case space with no shading device or with curtains and compared to fix shading devices.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.9
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• pp.207-214
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• 2019

Natural ventilation through openings such as windows in school buildings is an efficient resource for natural cooling during the intermediate season of the year. Because the natural ventilation uses the wind outside the building, the amount of ventilation will depend not only on the wind speed and wind direction but also on the window layout and open window ratio. Therefore, in this study, the natural ventilation plans of school classroom windows are divided into 4 types and 8 cases as shown in Table 1. The characteristics of cooling effect by natural ventilation are simulated by applying Energyplus's Airflow Network Model and the comfort of the occupants is evaluated by the number of hours included in the 80% acceptability range of the ASHRAE Standard 55-2010 adaptive comfort model for the weekdays (Monday-Friday) and the class hours (08: 00-19: 00). Based on the analysis results of the above, this study presents basic data related to classroom cooling plan using intermediate season natural ventilation.

• Advances in concrete construction
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• v.14 no.3
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• pp.215-225
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• 2022

Thermal comfort and energy conservation are critical issues in the building sector. Energy consumption in the building sector should be reduced whilst enhancing the thermal comfort of occupants. Concrete is the most widely used construction material in buildings. Its thermal conductivity (k-value) has a direct effect on thermal comfort perception. This study aims to find the optimum value of replacing the normal aggregate with lightweight expanded clay aggregate (LECA) under high strengths and low thermal conductivity, density and water absorption. The k-value of the LECA concrete and its physical and mechanical properties have varying correlations. Results indicate that the oven-dry density, compressive strength, splitting tensile strength and k-value of concrete decrease when normal coarse aggregates are replaced with LECA. However, water absorption (initial and final) increases. Thermal conductivity and the physical and mechanical properties have a strong correlation. The statistical optimisation of the experimental data shows that the 39% replacement of normal coarse aggregate by LECA is the optimum value for maximising the compressive and splitting tensile strengths whilst maintaining the k-value, density and water absorption at a minimum.

• Structural Monitoring and Maintenance
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• v.11 no.2
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• pp.87-100
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• 2024

Traffic-induced vibrations (TIVs) possess the potential to induce structural damage in both historical and critical edifices. Recent investigations have underscored the adverse impact of TIVs within buildings, manifesting as a deleterious influence on the quality of life and operational efficiency of occupants. Consequently, these studies have dichotomized TIVs into two primary limit categories: the threshold for vibrations capable of causing structural damage and the limit values associated with human comfort. In this current research endeavor, an exhaustive analysis of peak ground acceleration (PGA), peak ground velocity (PGV), peak ground displacement (PGD), and the frequency spectrum of ground motions originating from diverse traffic sources has been conducted. Furthermore, the detrimental repercussions of these vibrations on structures, gauged through the assessment of the peak particle velocity (PPV) parameter, have been systematically evaluated. The findings of this study elucidate that TIVs within the examined structures do not attain magnitudes conducive to structural compromise; however, the levels surpassing human comfort limits are evident, attributable to specific sources and distances. Moreover, this investigation sheds light on the absence of comprehensive criteria and guidelines pertaining to the assessment of TIVs in structures within the Turkish Building Seismic Design Code 2018. It seeks to raise awareness among building constructors about the critical importance of addressing this issue, emphasizing the imperative for guidelines in mitigating the impact of TIVs on both structural integrity and human well-being.

• Journal of the Korean housing association
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• v.18 no.2
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• pp.21-27
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• 2007

Various buildings constructed by environmentally friendly resources are being built in KOREA. Especially as the wood has distinctive ecological merits in comparison with reinforced concrete and brick, the buildings made by the wood are acknowledged with its superiority of ecological value. Enough field studies for their thermal environment, however, haven't been done. In this study, to investigate indoor environmental condition and occupants' response to it of Log Cabin in Gyeongsangnam-do Hamyang Country Jirisan Natural Recreation Forest, examination of indoor thermal environment and field subjective evaluation have been done in that fundamental information of thermal environment characteristics can be suggested. The results are following; 1) Thermal environment of the Log Cabins; Indoor and outdoor mean dry bulb temperature were $21.9^{\circ}C$ and $-3.1^{\circ}C$, and Indoor and outdoor average relative humidity were 25.8% and 52.1%. These results are below ASHRAE; dry bulb temp. $22.0^{\circ}C$, humidity 30%, and above domestic standards; dry bulb temp. $18{\sim}20.0^{\circ}C$, humidity $40{\sim}60%$. 2) Result of subjective evaluation; Thermal sensation and its comfort were evaluated as 'slightly uncomfortable' because of 'slightly warm'. And humid sensation and its comfort were evaluated as 'slightly uncomfortable' because of 'slightly warm'. 3) Result of vertical temperature and humidity; Vertical temperature difference from head to ankle was $0.54^{\circ}C$ which means most occupants may feel comfortable.

• Science of Emotion and Sensibility
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• v.16 no.3
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• pp.311-318
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• 2013

This research examined the validity of whether the PMV index-based comfort- or uncomfort-indoor environments could be classified by the facial skin temperature, one of the physiological indicator for human. To do this, we distinguished between a comfort thermal environment and an uncomfort thermal environment using the PMV value, and then facial skin temperatures were measured in both environments. As a result, the facial skin temperature of occupants were different between the comfort- and uncomfort-indoor environments. It suggested that the facial skin temperature could be used in shaping the comfortable indoor environment based on the PMV index. While this result suggested the PMV index-based on comfort and uncomfort indoor environments could not be valid, because the facial skin temperature was lower in the uncomfort thermal environment than in the comfort thermal environment.

• International conference on construction engineering and project management
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• 2024.07a
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• pp.540-549
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• 2024

Despite the acknowledged benefits by incorporating daylighting in the lighting system of office buildings to enhance energy efficiency and ensure occupants' well-being, a significant gap in understanding the integration of daylighting control system (DCS) with Building Information Modeling (BIM) exists, which can lead to improved energy efficiency and enhanced building design, specifically regarding the impact of daylight on occupant comfort. Previous studies have highlighted the potential of BIM to revolutionize both architectural design and building performance. However, an untapped potential of BIM in facilitating daylighting control in office areas is yet to be explored. The significance of this study lies in prioritizing occupants' well-being and enhancing building performance. This research identifies the feasibility of BIM-enabled DCS through a literature review from three perspectives: BIM-enabled DCS and daylight strategies, BIM-assisted façade system improvement, and user-centric daylight utilization within BIM platforms. As for results, a sensor network diagram illustrating network structure, data flow, and connections between devices of BIM enabled daylight control system for office buildings are established. Additionally, a BIM assisted daylight control strategy diagram is presented to outline user-centric control facilitated by BIM platform. In terms of contribution to the body of knowledge, this research will provide a comprehensive synthesis of existing literature in this domain. Additionally, this research could provide architects, DCS designers, and sustainable building professionals with potential advancements and inspirations to promote energy-efficient and user-centric building design in the future.

• The Journal of the Acoustical Society of Korea
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• v.42 no.1
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• pp.42-49
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• 2023

Poor indoor acoustic environments negatively affect occupants. Previous research has shown that indoor acoustic environments affect not only task performance and job satisfaction of the occupants, but also their health and well-being. This study aimed for evaluating indoor acoustic environments of open-plan offices located in public buildings in Korea. It also aimed to review the matters that need to be considered in order to improve occupants' acoustic comfort. Indoor noise levels were measured in 13 sites; the measurements were conducted for five consecutive working days from Monday to Friday. The noise levels were evaluated based on the levels recommended by the ISO and the EU ALDREN project. The study found that most of the indoor noise levels measured in the sampled sites during the working hours met the ISO standard. In the case of the levels under unoccupied conditions at night, those at three sites did not meet the recommendation of the ALDREN. In addition, some characteristics of the sites had significant effects on the noise level. Since the exact acoustic performance of the building envelope could not be identified, future research is needed for investigating the relationship between accurate building performance and indoor acoustic environments.

• KIEAE Journal
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• v.16 no.5
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• pp.29-37
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• 2016

Purpose: Indoor thermal comfort can be identified by combination of temperature, humidity, and air flow, etc. However, most thermal indexes in regard to thermal comfort are temperature dominant since it has been considered as a significant factor affecting to indoor thermal comfort The purposes of this study are to investigate indoor neutral temperature range of young Koreans with humidity perception, and to introduce a neutral temperature for temperature preference as well as temperature sensation in order to define the neutral temperature range chosen by occupants. It could be used as basic data for heating and cooling. Method: 26 research participants volunteered in 7 thermal conditions ($18^{\circ}C$ RH 30%, $18^{\circ}C$ RH 60%, $24^{\circ}C$ RH 30%, $24^{\circ}C$ RH 40%, $24^{\circ}C$ RH 60%, $30^{\circ}C$ RH 30%, $30^{\circ}C$ RH 60%) and completed subjective assessment in regard to temperature/humidity sensation and preference twice per condition in an indoor environmental chamber. Result: In RH 30%, sensation neutral temperature was $25.1^{\circ}C$ for men and $27.0^{\circ}C$ for women, and preference neutral temperature was $25.5^{\circ}C$ for men and $27.8^{\circ}C$ for women. In RH 60%, sensation neutral temperature was $23.6^{\circ}C$ for men and $25.9^{\circ}C$ for women, and preference neutral temperature was $23.4^{\circ}C$ for men and $26.3^{\circ}C$ for women. Neutral temperature increased with increasing relative humidity. Women were sensitive to humidity changes. Men expressed humidity changes as temperature variations. In most conditions, preference neutral temperatures were higher than sensation neutral temperatures, however, the preference neutral temperature for men in humid condition was lower than the sensation neutral temperature.