• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.11a
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• pp.107-111
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• 2003

The need for this study must be considerable, as being activate of green roofs research that the organization and construction obtain access to more development technologies. Nevertheless, the green roofs system has begun to apply since 1980's, the green roofs technology was restricted to develop without verification of technologies such as a load or water leakage. There is a limit as urethane waterproofing to almost domestic waterproofing materials and methods of construction for general green roofs. The introduction of materials and methods of construction which are appropriated to property of green roofs could be a decisive factor in a long-range durability and economical maintenance cost, moreover, it support to variety construction system and organization. This present paper describes a necessity of waterproofing and root barrier system is one of the sub-organization based on green roofs construction, which have enormously large impact on the durability.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.69-75
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• 2014

The priority of repair areas are chosen with the probability distribution of 0.3mm wide crack and carbonation induced corrosion. Data is analyzed and evaluated based on the 28 section of Precise Inspection for Safety and Diagnosis (PISD) in seoul. As the crack is distributed in log-normal, the carbonation and cover are in normal distribution. To have rational in repair sections among 503 sheets of underground structure, it is adopted the reliability index as well as the environment factors: strength, sonic speed, $CO_2$ concentration, corrosion, and content of chloride.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.4
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• pp.149-160
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• 2000

As systematic methodologies are required for the evaluation on the durability of reinforced concrete structure, it is necessary to study and examine every factor which deteriorates the durability of structures. This paper aims to define factors affecting rebar corrosion and to establish a basis for a prediction of serviceability, regarding a state of harmful corrosion as a state when crack begins on the surface of concrete. The study results are followings; The corrosive current has changed by types of mixture, and this property enables the evaluations of corrosion resistance by mixture and concrete cover. The specimen using AE superplasticizer has better corrosion-resistance properties than non-AE specimen, as well those having low W/C and high unit cement weight. The procedure for calculation of durable year in this study is able to use as an indicator to establish mixture factors such as unit cement weight, W/C, amount of admixture, etc.

• Journal of the Korea Society of Computer and Information
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• v.21 no.11
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• pp.135-139
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• 2016

This paper investigates the empirical implications. The research question of this study is to verify the influences of psychological and environmental factors toward performance satisfaction and durability of learning in E-Learning University. For empirical verification, a survey was conducted targeting 500 students in E-learning Universities. The results show that actional environment on academic satisfaction in learning is the most important factor followed by physical environment, internal motivation, and academic burnout. The effect of psychological factors on learning persistence was important in the order of academic vision, internal motivation, actional environment and physical environment. The effect of academic satisfaction on learning durability proved to be statistically significant. The results suggest that actional environment should be considered with top priority to increase the academic satisfaction. learning satisfaction, academic vision, and academic satisfaction to enhance students' intention to continue studies are important. Academic burnout has a negative effect on both academic satisfaction and learning persistence, suggesting that this aspect should be properly addresses. The effects of student background variables in E-learning were explored.

• Journal of the Korea Institute of Building Construction
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• v.4 no.1
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• pp.111-118
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• 2004

The need for this study must be considerable. as being activate of green roofs research that the organization and construction obtain access to more development technologies. Nevertheless, the green roofs system has begun to apply since 1980's, the green roofs technology was restricted to develop without verification of technologies such as a load or water leakage. There is a limit as urethane waterproofing to almost domestic waterproofing materials and methods of construction for general green roofs. The introduction of materials and methods of construction which are appropriated to property of green roofs could be a decisive factor in a long-range durability and economical maintenance cost, moreover, it support to variety construction system and organization. This present paper describes a necessity of waterproofing and root barrier system is one of the sub-organization based on green roofs construction. which have enormously large impact on the durability.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.1
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• pp.122-131
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• 1992

An expert system is developed which can design the power transmission involute cylindrical gears on the basis of strength and durability. Bending strength, surface durability, scoring, and wear probability are considered as the basis. The basic components of the expert system are knowledge base, inference engine, and working memory. The knowledges in knowledge base are classified hierarchically into the knowledges used in selection of gear type, selection of materials, and determination of K factor and are represented by rules. In the inference engine two inference methods are implemented with the depth first search method. For-ward chaining method is introduced in the selection of gear type and materials and in the determination of K factor. Backward chaining method is introduced in the detailed design of module and face width in accordance with the validation of strength. And inference efficiency is achieved by constructing the part needing a lot of numerical calculations in strength estimation separately from inference mechanism. The working memory is established to save the results during inference temporarily. In addition, design database of past design results is built for consultation during design and knowledge acquisition facility, explanation facility, and user interface are included for the usefulness of user. This expert system is written with the PROLOG programming language and the FORTRAN language in numerical calculation part which interfaced with PROLOG and can also be executed on IBM-PC compatible computer operated by MS-DOS alone.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.5
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• pp.66-72
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• 2016

Gearboxes are mechanical components that transmit power by adjusting input and output speed and torque. Their design requirements include small size, light weight, and long lifespan. We have investigated the effects of carrier pinhole position error on the load sharing and load distribution characteristics of a planetary gear set with four planet gears. The simulation model for a simple planetary gear set was developed and verified by comparing analytical results with a putative model. Then, we derived the load sharing and load distribution characteristics under various pinhole position error conditions using the prototypical simulation model. The results showed that the mesh load factor and face load factor increased with the pinhole position error, which then influenced the safety factor for tooth bending strength and surface durability.

• Journal of Fashion Business
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• v.21 no.2
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• pp.91-104
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• 2017

This study analyzed the difference of selection criteria when buying socks and wearing satisfaction related to socks according to demographic characteristics and fashion interest degree for the adults in their from 20s to 40s. Factor analysis, t-test, ANOVA, and Duncan multiple range test were used for data analysis. The result of factor analysis for selection criteria when buying socks showed that the drawn factors were design and coordination, hygiene and wearing comfort and practicality. The difference analysis results about selection criteria when buying socks showed that design and coordination, hygiene and wearing comfort, and practicality were significantly different according to gender, age, and occupation, and that design and coordination and practicality were significantly different according to marital status. The result of difference analysis for selection criteria when buying socks according to fashion interest degree showed that design, coordination, hygiene, wearing comfort and practicality were significantly different. The result of factor analysis for wearing satisfaction of socks showed that the drawn factors were wearing comfort, hygiene, durability, and design. The difference analysis results about wearing satisfaction of socks showed that design was significantly different according to gender and marital status, wearing comfort and design significantly different according to age, wearing comfort, hygiene, and design were significantly different according to occupation. According to fashion interest degree, wearing comfort and design showed the significant difference.

• Journal of the Korea Fashion and Costume Design Association
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• v.12 no.2
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• pp.75-90
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• 2010

Teenagers are considered as one of important consumer groups by marketers because of their high purchasing power and impulsive purchasing propensity. Especially high school girls are most significant purchasing group of them. The purpose of this study is to investigate the effect of high school girls' lifestyle on shoes purchasing behavior and shoes wearing satisfaction. This study surveyed 428 high school girls in Seoul and Chonbuk area. Data were statistically analyzed using SAS 9.1.3 for Window. Major statistical methods are factor analysis, Cronbach's ${\alpha}$ coefficient, cluster analysis, frequency analysis, Chi-square test, multiple regression analysis, ANOVA and Duncan test. The shoes purchasing behavior is significantly different according to students' lifestyle. Activity-pursuing group's major shoes purchasing factor is practical use and fashion & scholar-pursuing group's major shoes purchasing factors are fashion and brand. Relationship between lifestyle and shoes purchasing pattern is as follows. Activity-pursuing group and fashion & scholar-pursuing group purchased shoes more frequently than family-pursuing group. Fashion & scholar-pursuing-group purchased shoes for the harmony of suit and shoes. As for wearing satisfaction, design is the primary factor and price was the least significant factor in sports shoes, while durability is the primary factor and material is the least significant factor for the casual shoes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.1 no.1
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• pp.9-19
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• 1981

Using superplasticizer or the methods of autoclave curing is the most typical and practical of the ways to make high strength concrete. In this study the high strength concrete piles by way of centrifugal forming and hand compacting, are put to the freezing and thawing test after the process of autoclave curing, water curing after steam curing, or stand water curing. And the relation of such piles to durability, the rate of strength decrease, and the rate of weight variation is shown. The durability of those test piles throughout freezing and thawing test proves to be comparatively sufficient in the above-mentioned curings when the piles contain a proper quantity of air. But it is also acknowledged that without A.E agent, the high strength concrete piles of autoclave curing is higher than those of the other curing in strength, but lower in modulus of dynamic elasticity and their durability factor after the test is much lower.