• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.1
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• pp.55-62
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• 2002

The upper wall-lower frame structures(mixed building structures) are usually composed of shear wall structure in the upper part of structure which is used as residential space and frame structure in the lower part of structure which is used as commercial space centering around the transfer system in the lower part of structure. These structures are characteristics of stiffness irregularity, mass irregularity, and vertical geometric irregularity. The purpose of this study is to investigate the nonlinear response characteristics and the seismic capacity of mixed building structures when the number of stories in the lower frame is varied. The conclusions of this study are following. 1) As the result of push-over analysis of structure such as roof drift(i.e. roof displacement/structural height) and base shear coefficient, when the stories of lower frame system are increased, base shear coefficient is decreased, but roof drift is increased. 2) According to an increase in stories of the lower fame, story drift and ductility ratio of upper wall system are decreased and behavior of upper wall system is closed to elastic. 3) When the stories of lower frame system are increased, the excessive story drift is concentrated on the lower frame system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.7
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• pp.369-374
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• 2015

This study analyzed analyzes the energy performance of six houses in Daejeon completed which were built in 2011. Observed The observed houses, which were all designed and constructed inof the same size and structure, are were highly insulated with triple Low-E coating windows; the insulation level of the walls is was $0.13W/m^2K$ and that of the roof is was $0.10W/m^2K$. As electric houses, all of the energy supplied to the houses, including for cooking, is was supplied by electricity. A and 3~4 kWp of photovoltaic system and a 3~5 kW of ground source heat pump (GSHP) were installed in each house tofor providing provide space heating/and cooling and hot water are installed. We constructed a Web-based remote monitoring system in order to understand energy consumption and the dynamic behavior of the energy system. T, and the results of our metering data analysis of 2013 are as follows. First, the annual residential energy consumption is was 4,400 kWh (${\sigma}=1,209$) and GSHP energy consumption is was 5,182 kWh (${\sigma}=1,164$). Second, residential energy consumption ranked highest in average energy usage, with at 45% of the total, followed by heating with at 30%, hot water supply with at 17% and cooling with at 6%. Third, the average energy independence rate is was 51.8%, the GFA (Gross gross floor area) criteria average energy consumption unit is was $48.7kWh/m^2yr$ (${\sigma}=10.1$), and the net energy consumption unit (except the energy yield of the PV systems) is was $24.7kWh/m^2yr$ (${\sigma}=8.8$).

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.12
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• pp.1070-1079
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• 2012

The impact energy absorbing is a very important characteristic of an aircraft to enhance the survivability of occupants when an aircraft is under the survivable accident such as an emergency landing condition. The impact energy is generally transmitted into the occupant and absorbed through a landing gear, a subfloor (lower structure of fuselage), and a seat. The characteristic of crash energy absorbing of a subfloor depends on the type of an aircraft, a shape of structure, and an applied material. Therefore, the study of crashworthiness characteristics of a subfloor structure is very important work to improve the safety of an aircraft. In this study, a finite element model of a narrow body fuselage section for the 80~90 seats regional aircraft was developed and crash simulation was executed using an explicit finite element analysis. Through survey of the impact energy distribution of each structural part of a fuselage and floor-level acceleration response, the crashworthiness characteristics and performance was evaluated.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.38-45
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• 2017

Objectives: Radon may be second only to smoking as a cause of lung cancer. Radon is a colorless, tasteless radioactive gas that is formed via the radioactive decay of radium. Therefore, radon levels can build up based on the amount of radium contained in construction materials such as phospho-gypsum board or when ventilation rates are low. This study provides our findings from evaluation of radon gas at facilities and offices in an industrial complex. Methods: We evaluated the office rooms and processes of 12 manufacturing factories from May 14, 2014 to September 23, 2014. Short-term data were measured by using real-time monitoring detectors(Model 1030, Sun Nuclear Co., USA) indoors in the office buildings. The radon measurements were recorded at 30-minute intervals over approximately 48 hours. The limit of detection of this instrument is $3.7Bq/m^3$. Also, long-term data were measured by using ${\alpha}-track$ radon detectors(${\alpha}-track$, Rn-tech Co., Korea) in the office and factory buildings. Our detectors were exposed for over 90 days, resulting in a minimum detectable concentration of $7.4Bq/m^3$. Detectors were placed 150-220 cm above the floor. Results: Radon concentrations averaged $20.6{\pm}17.0Bq/m^3$($3.7-115.8Bq/m^3$) in the overall area. The monthly mean concentration of radon by building materials were in the order of gypsum>concrete>cement. Radon concentrations were measured using ${\alpha}-track$ in parallel with direct-reading radon detectors and the two metric methods for radon monitoring were compared. A t-test for the two sampling methods showed that there is no difference between the average radon concentrations(p<0.05). Most of the office buildings did not have central air-conditioning, but several rooms had window- or ceiling-mounted units. Employees could also open windows. The first, second and third floors were used mainly for office work. Conclusions: Radon levels measured during this assessment in the office rooms of buildings and processes in factories were well below the ICRP reference level of $1,000Bq/m^3$ for workplaces and also below the lower USEPA residential guideline of $148Bq/m^3$. The range of indoor annual effective dose due to radon exposure for workers working in the office and factory buildings was 0.01 to 1.45 mSv/yr. Construction materials such as phospho-gypsum board, concrete and cement were the main emission sources for workers' exposure.

• Parasites, Hosts and Diseases
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• v.53 no.5
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• pp.553-559
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• 2015

Research on micro-level assessment of the changes of socio-economic status following health interventions is very scarce. The use of household asset data to determine wealth indices is a common procedure for estimating socio-economic position in resource poor settings. In such settings information about income is usually lacking, and the collection of individual consumption or expenditure data would require in-depth interviews, posing a considerable risk of bias. In this study, we determined the socio-economic status of 213 households in a community population in an island in the north-western Tanzania before and 3 year after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention to control schistosomiasis and intestinal worm infections. We constructed a household 'wealth index' based housing construction features (e.g., type of roof, walls, and floor) and durable assets ownership (e.g., bicycle, radio, etc.). We employed principal components analysis and classified households into wealth quintiles. The study revealed that asset variables with positive factor scores were associated with higher socio-economic status, whereas asset variables with negative factor scores were associated with lower socio-economic status. Overall, households which were rated as the poorest and very poor were on the decrease, whereas those rated as poor, less poor, and the least poor were on the increase after PHAST intervention. This decrease/increase was significant. The median shifted from -0.4376677 to 0.5001073, and the mean from -0.2605787 (SD; 2.005688) to 0.2605787 (SD; 1.831199). The difference in socio-economic status of the people between the 2 phases was highly statistically significant (P<0.001). We argue that finding of this study should be treated with caution as there were other interventions to control schistosomiasis and intestinal worm infections which were running concurrently on Kome Island apart from PHAST intervention.

• The Korean Journal of Petroleum Geology
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• v.10 no.1_2 s.11
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• pp.18-22
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• 2004

To identify and interpret the distribution and the characteristics of the gas hydrate layers in the Ulleung Basin, we have surveyed and gathered the multi-channel seismic data, Chirp sub-bottom profiler, SeaBeam and 12 m piston core samples since 1996. In previous works, high-resolution seismic profiles showed acoustic anomalies such as acoustic void, acoustic turbidity and pock mark which indicate the presence of gas-charged sediments. The patterns of horizontal degassing cracks originated from free methane expansion is the strong indicator of shallow gas-charged sediments in the core samples. The observation of submarine slides and slumps from destabilizing the sediments in the southern part of the Ulleung Basin may also point out that the gas had been released from gas hydrate dissociation during lowstand of sea level. The multi-channel seismic data show BSR, blanking and phase reversal. The gas hydrate layers above which large-scale shallow gases are distributed exist at the depth of about 200 m from the sea-floor with water depth of 2,100 m. From the interpretation of seismic sections in the southern Ulleung Basin, gas hydrate layers occur in the Pleistocene-Holocene sediments. These gas-charged sediments, acoustic anomalies and BSR may be all related to the existence of gas hydrate layers in the study area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.131-138
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• 2016

This study reviewed the status of domestic and foreign Architectural Information Systems and related laws, analyzed the state of the architectural service industry, and proposed the phased introduction of BIM into Architectural Information Systems. The adoption of BIM in Architectural Information Systems both at home and abroad is generally at an unsatisfactory level, with only Singapore assuming a leading role in this area through activities such as the provision of a separate BIM submission service. Since it is desirable for BIM to be applied to additional types of architecture when the architectural licensing procedure is introduced, the different phases of adoption were set after analyzing the scales and types of architecture as defined in related laws. By analyzing the participation rates of architectural design firms in each scale of architecture design, the results demonstrated that, as the number of floors and total floor area in the building increases, the proportion of small scale architectural design firms involved decreases, while that of large-scale architectural design firms increases. The adoption of BIM is occurring mostly within large-scale architectural design firms, which is why it is desirable for its introduction into Architectural Information Systems to be separated into phases from large-scale buildings to increasingly small-scale architecture. In conclusion, this study divided the adoption of BIM in Architectural Information Systems into 6 stages and, following the Architectural administration procedure, established a segmented road map for the gradual activation of BIM.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.468-477
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• 2019

This study analyzed the major contents and results of revision through an analysis of the specifications and the field survey to revise the construction cost calculation criteria. The result of the survey found that the background processing difficulty was reduced due to an improvement of the quality level of the field floor, and the enhancement of the material's function brought a decrease in construction time and the application of various construction methods. In addition, the application of combined waterproofing methods using more than one material was increasing and the productivity differed according to the site and location. Based on these results, waterproof items were subdivided and applied to the composite construction method, and the input items were differentiated according to the material and construction method. The adequacy of the construction calculation criteria was ensured by presenting the criteria classified according to the construction area, and deleting the items that are not applicable and amending them to make them suitable for the specifications by reflecting the actual conditions of the construction on the site.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.4
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• pp.39-45
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• 2018

Purpose : The purpose of this study is to investigate the effect of core motion pattern on abdominal muscle thickness on unstable support surface using sling suspension system and to provide an effective exercise program for therapeutic rehabilitation in clinical practice. Methods : In this study, we used the flank exercise using a sling. It was intended for 21 healthy men and 9 healthy women. Before and after the exercise of the subjects, abdominal muscles (EO, IO, TrA the thickness of the muscle) was determined using a diagnostic ultrasonic apparatus. The period of exercise was 3 times a week for 6 weeks. The exercise for each group started with 3 sets per week and 1 set per week was added. A description of the method and attitude of each exercise is as follows. First, the push-up flank 's exercise position is to put both feet on the sling and hold the floor with both hands. Second, the side flank's exercise postures take the side flanks, while the two legs hang on the sling and one arm supports the body with an articulated bend (about $90^{\circ}$). Third, the elbow flank's exercise position is to put the two legs on the sling, and take a flank posture with the arms bent and joint bending (about $90^{\circ}$). Results : There was a significant difference in the thickness of the muscle in the three flank movements after the exercise (p<.05). The most significant difference was in the change of the muscle thickness in the abdominal muscle, the outer muscle, and the stomach in the elbow flank exercise after exercise. There was a significant difference between the mean thickness of the abdominal muscles according to the flank type after exercise (p<.05). Conclusion : In flank exercise for core stabilization using sling, it is considered effective to strengthen the abdominal muscles by considering the support surface, difficulty level, change of movement pattern.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.4
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• pp.175-185
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• 2022

Purpose : This study was conducted to determine the effect of Kegel exercise using a pressure biofeedback unit (PBU) for 2 weeks on maximum voluntary ventilation (MVV) and abdominal muscle thickness based on previous studies. Methods : The subjects of this study were 20 healthy female students in their 20s. Subjects were randomly assigned to two groups. Eleven subjects were assigned to the experimental group (EG) and 9 subjects were assigned to the control group (CG). Subjects measured MVV with a spirometer. In hooklying position, transverse abdominis (TrA), internal oblique (IO), and external oblique (EO) of the dominant side were measured using ultrasound. For the measurement value, the average value of three times was adopted. After 2 weeks of intervention, the measurements were measured in the same way. In the EG, pelvic setting training using PBU was performed before Kegel exercise. The PBU was first placed at the waist in the Kegel exercise position and the starting pressure was set at 40 mmHg and adjusted to 60 mmHg through pelvic floor muscle contraction. After performing pelvic control using PBU, Kegel exercise was performed with 8 seconds of contraction, 8 seconds of relaxation, and 3 sets of 10 reps per set. A significance level of 𝛼=.05 was used to verify statistical significance. Results : In the variable of MVV, a significant increase was confirmed in the EG (p<.05). In the abdominal muscle thickness variable, significant increases were confirmed in IO and TrA in the EG (p<.05). In addition, a significant increase in IO was confirmed in the CG (p<.05). Significant increases in IO and TrA were confirmed between groups (p<.05). Conclusion : Based on the previous study, this study confirmed that Kegel exercise using a PBU had a positive effect on MVV and abdominal muscle thickness based on a 2-week intervention.