• Journal of the Korean Society of Safety
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• v.28 no.5
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• pp.71-77
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• 2013

This Study aims at investigating actual condition on attending school road of children and analyzing empirically the characteristics of cognition and the influence of safety on school road. This study findings are as follows : 1) Walking alone to go to school is the highest rates among Commuting Mode, and Commuting distance to school is nearly doubles than range of school zone(300 m). 2) Among characteristics of urban spatial structure affecting on influence classify safety of school road, 'Commuting Distance' has been drawn to most influential variable. Especially, there are 4 types classified by commuting distance and it became obvious that the longer the distance, the lower the safety score(under 127 m=76.9 points, Over 451 m=58.3 points). 3) As a result of investigating the influence of Safety on attending school road, Vehicle commuting speed urder 127 m as internal of school zone, and Walking and crossing convenience over 451 m as external of school zone have a lot of influence on safety cognition on school road. Therefore Safety on school road should be considering the commuting distance to school among surrounding characteristics, needed for improvement plan and program based on real safety cognition of children.

• Progress in Superconductivity and Cryogenics
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• v.25 no.3
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• pp.28-33
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• 2023

Magnetic relaxation properties of pure MgB₂ powder samples and diluted water-treated MgB₂ powder samples were investigated. The magnetic field H-dependence, m(H), and the time t-dependence, m(t), of the magnetic moment m were measured and analyzed using the PPMS-VSM magnetometer equipment, respectively. The m(t) reduction rates of pure MgB₂ powder samples and diluted water-treated MgB₂ powder samples decreased to about 0.7 ~ 1.8% and 0.6 ~ 1.0% for about 7200 s, respectively, at temperature T = 15 K. The magnetic relaxation properties of the two types of MgB₂ powders were analyzed by calculating the magnetic relaxation rate S = -dln(M_irr)/dln(t) values according to Anderson-Kim theory. The magnetic relaxation ratio S values of the two types of MgB₂ powder samples were almost similar. As a result of the quantum creep effect, the constant magnetic relaxation rate S characteristic was confirmed at a temperature range of T = 10 K or less.

• Journal of the Korean housing association
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• v.14 no.4
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• pp.57-67
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• 2003

The purpose of the study is to propose the basic data for an aged residential building suitable for Korean environment and it is based on the outcomes of investigation on The Aged Care Residential Service in Australia including the scale and arrangement of private zone and specific characteristics of each compartment. The brief outcomes of the research are follows as. - The Aged Care Residential Services have been functionally running divided into Nursing home, Hostel and Retirement Village by the classification standard of the residential classification scale. - Single bed rooms have 75% of total residential area and the square of single bed room is about $20\textrm{m}^2$and that of two-bed room is about $31\textrm{m}^2$. - There are two types of ensuite such as one single-bed room and one ensuite and bed room for two or three persons and ensuite type. The square of ensuite varies as single is 50∼60%, single for public is 25∼30%, and double for public is 15∼20%. - Assisted bathrooms are generally located in the middle of building and it is suggested to be occupied about $1.25\textrm{m}^2$ per person. Sitting rooms are two types such as room type whose square has about $12\textrm{m}^2$ and a lounge type has $16\textrm{m}^2$.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.2
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• pp.100-108
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• 2000

As U.S. congress and I.M.O. have recently adopted strengthened MARPOL73/78 regulations on marine pollution, it is necessary to develope a new type of tankers such as Double hull tanker(D/H Tanker) and Mid-deck tanker(M/D Tanker) and so on. Because most of researches are concentrated on the volume of oil spill due to collision of ships, in this paper, a structural design program for D/H Tankers and M/D Tankers is developed to suggest the effective type of tankers by comparing structural characteristics between their types. By this program, minimum hull weight designs of D/H tankers and M/D tankers considering tank arrangement are performed and the design results are compared each other. The efficient types of hull structure for the minimum weight design between D/H tankers and M/D tankers is proposed.

• Journal of the Korean housing association
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• v.17 no.5
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• pp.147-157
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• 2006

A study on Composing Unit Spaces of Apartment Houses according to the Differentiation in Lifestyle by survey on preferences. The purpose of this study is to propose composition models of unit spaces for 85m2 net area apartment houses by lifestyle types. This study set up a hypothesis that there is a critical divergence of preferences in composition types of unit spaces according to lifestyle. To prove the hypothesis, investigation on variable floor plans of apartments to extract spatial composition types of units and questionnaire survey on lifestyleand preferences for composition types were implemented. To extract several factors regarding, characteristics of lifestyle, factor analysis, was implemented for each variable. Cluster analysis was conducted to cluster interviewees by similarity of lifestyle. To identify and define how each factor reacts, ANOVA and cross tabulation analysis between factors and clusters were used. The type of spatial composition was analyzed by plane characteristic, spatial relation and spatial usability on the basis of apartment plate type. As a result, lifestyle was divided into three types: reasonable lifestyle, trend-seeking lifestyle and conservative lifestyle. As, the result of investigating characteristics for the type of spatial composition according to the type of lifestyle, preferred types and main districts were different. Therefore, the hypothesis was proved.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.2
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• pp.147-158
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• 2016

Objectives: The objective of this study was to evaluate the assessment of exposure to welding fume and heavy metals among construction welders. Methods: Activity-specific personal air samplings(n=206) were carried out at construction sites of three apartment, two office buildings, and two plant buildings using PVC(poly vinyl chloride) filters with personal air samplers. The concentration of fumes and heavy metals were evaluated for five different types of construction welding jobs: general building pipefitter, chemical plant pipefitter, boiler maker, ironworker, metal finishing welder. Results: The concentration of welding fumes was highest among general building pipefitters($4.753mg/m^3$) followed by ironworkers($3.765mg/m^3$), boilermakers($1.384mg/m^3$), metal finishing welders($0.783mg/m^3$), chemical pipefitters($0.710mg/m^3$). Among the different types of welding methods, the concentration of welding fumes was highest with the $CO_2$ welding method($2.08mg/m^3$) followed by SMAW(shield metal arc welding, $1.54mg/m^3$) and TIG(tungsten inert gas, $0.70mg/m^3$). Among the different types of workplace, the concentration of welding fumes was highest in underground workplaces($1.97mg/m^3$) followed by outdoor($0.93mg/m^3$) and indoor(wall opening as $0.87mg/m^3$). Specifically comparing the workplaces of general building welders, the concentration of welding fumes was highest in underground workplaces($7.75mg/m^3$) followed by indoor(wall opening as $2.15mg/m^3$). Conclusions: It was found that construction welders experience a risk of expose to welding hazards at a level exceeding the exposure limits. In particular, for high-risk welding jobs such as general building pipefitters and ironworkers, underground welding work and $CO_2$ welding operations require special occupational health management regarding the use of air supply and exhaust equipment and special safety and health education and fume mask are necessary. In addition, there is a need to establish construction work monitoring systems, health planning and management practices.

• Journal of the Korean Society of Costume
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• v.62 no.7
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• pp.13-28
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• 2012

This study examines history of Korean peony patterns and characteristics of peony patterns on the fabric. It is classified according to expression methods, and it analyzes the characteristics of 71 kinds of peony woven on 66 Korean fabrics. First, it was observed that 38 of the 66 studied fabrics (57.6%) were relics from the 17th century, and from this it can be deduced that the peony patterns began to appear regularly around the latter half of the 16th century and were used habitually in the 17th century. Second, 71 kinds on 66 fabrics can be divided into Real Type, Design Type, and Abstraction Type according to expression methods. Among these types, 49 kinds of them are Real Types (69.0%), forming the greatest part and 19 kinds belonging to the Design Type (26.8%), and lastly, 3 kinds were under the Abstraction Type (4.2%). In particular, peony patterns of Design Types and Abstraction Types from the 17th century and from the 19th century to the 20th century were more prevalent, compared with those before the 16th century or the 18th century. Third, Real Types shown on the Korean fabrics are subdivided into 9 types, and the Real Type A among them, which describes to be as real as possible, is 12 kinds, the largest number of them. Therefore, real and natural pattern of peony is the favorite type in Korea, while rather emphasized pattern of peony is the more preferred pattern in China. And also Design Types are subdivided into 6 types again; There are 6 kinds of design type A, the largest part of Design Types. Patterns of Design Type A are most similar to real peony flowers, but more simplified than the Real Type A. This result also contrasted with the trend in China, where the Design Type C, expressed petals in detail was the favored pattern. Fourth, 9 kinds of unique types are found in Korean fabrics, especially Real Type M has not been shown on Chinese fabrics. Real type M, consisting of two parts, inner and outer, where two curve lines between two parts appear as antennas of a butterfly.

• Journal of Korean Society of Steel Construction
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• v.20 no.6
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• pp.793-805
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• 2008

Recently, steel modular systems are developed and have been applied to the projects requiring fast construction such as military barracks and vertical expansion of school buildings. The existing modular system with standard module of ${6m\times3m}$ has a problem that many columns are duplicated in the module connection and the wall thickness increases. In this study, $12m{\times}3m$ module is proposed to solve this problem. Various types of beam-middle column connection which are essential for realizing the $12m{\times}3m$ module are proposed and their maximum load capacity and failure mode are analytically and experimentally evaluated. The comparison between analytical and experimental results shows that the maximum axial load and failure mode can be accurately estimated by finite element analysis. Some connection types which have higher failure load than the design load of the column, can be used as the beam-middle column connection detail of the $12m{\times}3m$ module.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.12
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• pp.1569-1575
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• 2012

In this study, ballistic impact effects on a helmet were investigated using the AUTODYN-3D program. Two types of materials were used for manufacturing the helmet: single Kevlar and Steel/Kevlar hybrid composites. Furthermore, two types of bullets were used in the simulation: steel spherical and 7.62 mm full-jacketed. In the simulation, the shape deformation of the projectile and internal energy were calculated. From the results, impact velocities above 655 m/s and 845 m/s were required to perforate the Steel/Kevlar helmet with steel spherical and 7.62 mm full-jacketed bullets, respectively. The results show that there was a large difference between the ballistic resistance of the Kevlar and Steel/Kevlar helmets. For the simulation on an NIJ-STD-0106.01 Type II helmet, a 7.62 mm fulljacketed bullet with a striking velocity of 358 m/s was used. Simulation results show that the Steel/Kevlar helmet could resist a 7.62 mm full-jacketed bullet traveling at 358 m/s.

• The Journal of Korean Association of Computer Education
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• v.16 no.6
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• pp.71-81
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• 2013

This study was executed to give a help in planning and implementing online learning. For this purpose this study investigated the effect of contents presentation types, levels and metacognition on concept map composition and learning process in online learning. Learning contents types were two, meaning-centered or context-centered. Contents levels were divided into two; basic or deficient. Metacognition was divided into two levels according to the scores of scale. Results showed that meaning-centered type(M=45.00, SE=1.97) got better scores in concept map than context-centered(M=34.71, SE=1.98), Presentation levels and metacognition had no significant influence on concept map. There were interaction effect(F=.002, p>.05) between presentation levels and metacogntion levels. The upper group in metacognition got higher score in deficient types whereas the lower group got higher score in basic type. In online learning process, learner's metacognition was an important factor to complement the contents' defect and lack.