• Journal of Radiation Protection and Research
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• v.37 no.4
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• pp.181-190
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• 2012

Naturally occurring radioactive materials (NORM) in building materials are main sources of external radiation exposure to the general public. The objective of this study was to assess external radiation dose in Korean dwellings due to NORM in concrete walls. Reference room model for dose assessment was made by analyzing room structure and housing scale of Korean dwellings. In addition, dose assessments were made for varying room sizes. Absorbed doses to air and effective dose rates were calculated using radiation transport code MCNPX. Assuming a reference room of $3{\times}4{\times}2.8m^3$, absorbed dose rates in air were 0.80, 0.97, 0.08 nGy $h^{-1}$ per Bq $kg^{-1}$ for uranium series, thorium series, and $^{40}K$, respectively. Effective dose rates were 0.57, 0.69, 0.058 nSv $h^{-1}$ per Bq $kg^{-1}$, respectively. Radiation dose resulting from concrete of ceiling and floor increased with room area while radiation dose from concrete of walls decreased with room area. Therefore, total radiation doses were almost the same for the varying room area from 5 to $30m^2$. Effective dose in Korean dwellings was calculated based on measurement data of NORM concentration in concrete and occupancy fraction of Korean population by location. Annual effective dose was 0.59 mSv assuming that indoor occupancy fraction was 0.89 and concentrations of uranium series, thorium series and $^{40}K$ were 26, 39, 596 Bq $kg^{-1}$, respectively. Finally, annual effective dose in Korean dwellings can be calculated by the following equation: Effective dose=indoor occupancy fraction${\times}8760\;h\;y^{-1}{\times}(0.57C_U+0.69C_{Th}+0.058C_K)$.

• Korean Institute of Interior Design Journal
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• v.23 no.2
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• pp.174-181
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• 2014

The purpose of the study for this thesis is to look into the status and issues of government office buildings since the self-government policy through comparing and analyzing government office buildings, between domestically and to provide improvement plans of the citizen cultural space and with the self-government budget, enhance the utility and efficiency of the government office buildings and to take a role of a reference in the future when citizen cultural space is formed in the government office buildings. As the result of the study, the space planning characteristics of government office building's citizen cultural space in terms of cultural administration is as follows. First, percentage of room to strengthen the sense of community is small. Therefore, the place where residents can argue there is a need. Second, it is necessary to expand the venue and art collection that are missing in public government buildings. Third, since the lecture room for lack of civic education, it should be taken into account when making cultural space for the citizens. Fourth, thread observatory and souvenir shops, providing information is not enough, it is to be further expanded. Fifth, rented facility for public is hall be provided with a diversity.

• Advances in nano research
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• v.6 no.1
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• pp.57-80
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• 2018

In this study, the thermal loading effect on free vibration characteristics of carbon nanotubes (CNTs) with multiple cracks is studied. Various boundary conditions for nanotube are taken in to account. In order to take the small scale effect, the nonlocal elasticity of Eringen is employed in the framework of Euler-Bernoulli beam theory. This theory states that the stress at a reference point is a function of strains at all points in the continuum. A cracked nanotube is assumed to be consisted of two segments that are connected by a rotational spring which is located in the position of the cracked section. Hamilton's principle is used to achieve the governing equations. Influences of the nonlocal parameter, crack severity, temperature change and the number of cracks on the system frequencies are investigated. Also, it is found that at room or lower temperature the natural frequency for CNT decreases as the value of temperature change increases, while at temperature higher than room temperature the natural frequency of CNT increases as the value of temperature change increases. Various boundary conditions have been applied to the nanotube.

• Agricultural and Biosystems Engineering
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• v.3 no.2
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• pp.65-72
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• 2002

Temperature is the most influential environment parameter which affects the quality change of agricultural products in cold storage. Therefore, it is essential to keep the uniform temperature distribution in the storage room. This study was performed to analyze the air movement and temperature distribution in the forced recirculating cold storage facility and to simulate optimum storage method of green groceries using 3-D CFD(three dimensional computational fluid dynamics) computer simulation which applied the standard $textsc{k}$-$\varepsilon$ turbulence model and FVM(finite volume method). The simulation was validated by the experimental results for onion storage and the simulation model was used to simulate the temperature and velocity distribution in the storage room with reference to the change of storage method such as location of storage, no stores, bulk storage, and pallet storage. In case of no stores, internal airflow was circulated without stagnation and consequently air movement and temperature distribution were uniform. In case of bulk storage, air movement was stagnated so much and temperature distribution of onion was not uniform. Furthermore, the inner temperature of onion roses more than the initial temperature of storage. In case of pallet storage, air movement and temperature distribution of onion were so uniform that the danger of quality change was decreased.

• KIEAE Journal
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• v.16 no.6
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• pp.115-122
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• 2016

Purpose: The study is to measure indoor air pollutants concentration of existing housing and to analyze the causes and assess in accordance with the government's criteria. The research result could be used as data for public health through indoor air quality management of existing housing and more as a reference for new housing. Method: It was investigated 24 middle class housings of metropolitan area in summer which have been built for the past 30 years. Concentration of HCHO, TVOC was investigated in living room at morning and night and concentration of $CO_2$ was investigated in living room and master bedroom at morning and night. SKT100-X5 was used for concentration of HCHO, TVOC and ZGm053UK for concentration of $CO_2$. Result: Average concentration of TVOC was 1.31 times more than that of HCHO and standard deviation of that was 1.73 times higher. Average concentration of $CO_2$ was almost nearly close to 1,000ppm being criteria of the Ministry of Environment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.259-264
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• 2001

It is necessary to predict the sound pressure level(SPL) in rooms before designing an apartment when exterior noises are produced. In order to predict SPL for an apartment that has some specific exterior noises, the following should be known: the characteristics of outdoor noise, sound insulation performance and sound level differences of each room. The purpose of this study is to find out the possibility of predicting sound pressure level of rooms in an apartment by analysing sound level differences among rooms. Sound sources used in this experiment are construction noise, aircraft noise, railroad noise, road traffic noise and white noise as a reference to compare with the previous four. These noises were recorded and reproduced by speaker. As a result, we found that within the sound reduction pattern, the sound difference level appeared uniform depending on the sound insulation characteristics of the windows installed when facing the noise source. When the windows having the same acoustic performance were installed, the SPL in each room resulted in nearly the same values.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.17 no.4
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• pp.539-547
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• 2010

Purpose: This study was done to determine the effects of aromatherapy on anxiety and discomfort for patients who were having colonoscopy. Methods: The study used a nonequivalent control group non-synchronized design. The participants were 48 people who were undergoing colonoscopy in a university hospital. The experimental group inhaled a blend of essential oil with neroli, camomile, lavender and lemon through an aroma stone for 5minutes before the examination. Then the aroma stone was put on the side of the pillow to spread the aroma scent in the room. The experimental group could inhale the aroma scent as soon as they came into the room and during the examination process. The control group received only fundamental nursing care. Results: Aromatherapy significantly decreased VAS anxiety. There were also significant differences in facial change and, tone change for objective discomfort. But there were no significant differences in subjective discomfort between the groups nor were there any significant differences in vital signs. Conclusion: Aromatherapy was perceived as an useful intervention to reduce anxiety and objective discomfort of patients receiving colonoscopy. The results of this study could be utilized as a clinical nursing intervention.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.3
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• pp.7-15
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• 2018

Purpose: The purpose of this study is to suggest the improvement of the architectural planning of public hospitals by analyzing the contents of the architectural planning and the trend of the recent ward planning. Methods: The study method was the drawing analysis of the wards in the public hospitals where facilities were improved including the ward-related literature survey. The scope of the study was the general wards. Results: As a result of the study, the area composition of the ward area, the number of beds per nursing unit, the floorplan types, and the unit space planning which is included the room composition, the room size, the bed clearance areas, and the improvements of the nursing space were suggested. Implications: The result of this research would be useful as a reference to design nurse area in the wards.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.7
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• pp.74-80
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• 2020

The ocher jjimjilbang for a single-person household that will be studied in this study is 2.1 ㎡ in size, and this study was conducted to implement well-being room heating that is beneficial to health by supplying radiant heat provided by hot water during room heating by embedding hot water panels in the walls of the ocher jjimjilbang to configure a hot water circulating system. In addition, the ocher bed and the ocher walls, which have been verified through many study findings and reference materials, were constructed so that the living life with a bed and the ocher jjimjilbang would be implemented simultaneously. As the mass flow rate of the hot water increased, the magnitude of the wall temperature rise thanks to the hot water increased, and as the flow rate of the hot water increased, the transfer rate of the heat transferred from the wall of the ocher jjimjilbang to the air inside the wall of the ocher jjimjilbang increased.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.2
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• pp.153-160
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• 2002

As a way to assess the reliability of programs for building energy analysis, verification experiment and calculation of heating load are simultaneously conducted for a well-defined test space. Experimental conditions are carefully set to minimize uncertainties associated with radiation heating, air change, infiltration, and room-to-room interaction. Dyna- mic load calculations using TRNSYS, which are performed for two different computation domains, rely on the energy rate control that represents inherent load characteristics of a space. The predicted instantaneous heating load favorably simulates the overall behavior the measured one, though the latter fluctuates much more rapidly than the former Comparison of the accumulative load between the experiment and calculations shows a close agreement within an engineering tolerance, regardless of the computation model. It is deduced from such findings that the present experimental results along with weather information can serve as a set of reference data for validating load calculation softwares from the users'standpoint. In order to enhance the completeness of this work, a complementary study on the cooling load for the same test space is highly recommended.