• Journal of Mechanical Science and Technology
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• v.15 no.9
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• pp.1217-1225
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• 2001

The governing equations are derived for the analysis of a stepped labyrinth gas seal generally used in high performance compressors, gas turbines, and steam turbines. The bulk-flow is assumed for a single cavity control volume set up in a stepped labyrinth cavity and the flow is assumed to be completely turbulent in the circumferential direction. The Moodys wall-friction-factor model is used for the calculation of wall shear stresses in the single cavity control volume. For the reaction force developed by the stepped labyrinth gas seal, linearized zeroth-order and first-order perturbation equations are developed for small motion about a centered position. Integration of the resultant first-order pressure distribution along and around the seal defines the rotordynamic coefficients of the stepped labyrinth gas seal. The resulting leakage and rotordynamic characteristics of the stepped labyrinth gas seal are presented and compared with Scharrers theoretical analysis using Blasius wall-friction-factor model. The present analysis shows a good qualitative agreement of leakage characteristics with Scharrers analysis, but underpredicts by about 20%. For the rotordynamic coefficients, the present analysis generally yields smaller predictied values compared with Scharrers analysis.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.9 no.2
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• pp.79-89
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• 1999

A quantitative fit test, condensation nuclei counting (Portacount 8025, TSI), was performed concurrently with a banana oil (isoamyl acetate: IAA) qualitative fit test (MSA) to evaluate reliability on IAA QLFT and correlation between two methods. One brands of quarter mask (3M model 7500 medium) was prepared for QLFT with HEPA filter and gas & vapor removing media, i.e., combination cartridge. 110 subjects (65 male, 45 female) were fit tested QNFT and QLFT each three times. For a wearer combination having a FF<10, as determined by CNC QNFT, the point es timate (${\beta}$-error) of the probability of that combination not being rejected by the banana oil QLFT was found to be 0.0 with 95% confidence that this statistic is not expected to exceed 0.15. For a wearer combination having a FF<100, as determined by CNC QNFT, the point estimate of the probability of that combination not being rejected by the banana oil QLFT was found to be 0.07 with 95% confidence that this statistic is not expected to exceed 0.13. The uncertainty associated with each estimate, however, is large due to the small number of study subjects with inadequately fitting respirators.

• Hwankyungkyoyuk
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• v.23 no.1
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• pp.50-63
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• 2010

This study is a qualitative case study aiming at understanding and finding out influential factors and barriers when school teachers choose Environmental Education as their Creative Discretionary Activities. To do this, this study focuses on the process of two teachers' choices of the Creative Discretionary Activities in two other elementary schools. The results of this research are follows. Two teachers' choices are affected by several influential factors, divided into external factors and internal factors. External influential factors include culture of school and education, media, chief education officers, parents and school. Internal influential factors are teachers' value and philosophy of education, teachers' experiences, teachers' capacity. These influential factors' forces aren't the same with each other. These influential factors, are influenced by educational, social, national, local, and school level indicated by Taylor et al's (1974) classification criterion. Especially, however, Korea's particular educational environment focusing on university entrance examination strongly affects teachers' choice. School factors also has a big strong effect on teachers' choice. Among others internal actors are the most serious influential factor affecting on teachers' choice.

• Korean Journal of Construction Engineering and Management
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• v.8 no.4
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• pp.99-109
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• 2007

Risk elements of highway safety facilities are affected by complex environments. Thus, risk-based approach for traffic safety facilities is needed. For this, in this study, qualitative and quantitative risk assessment methodology and procedure for highway safety facilities is proposed, which can be used as risk-based approach incorporating VE process. Also, for the quantitative risk assessment, event tree using EPDO(Equivalent Property Damage Only) with respect to frequency and magnitude of risk events is introduced. As a result, risk index of alternative 1(140cm) and 2(127(cm) which can be used as performance factor in VE approach are estimated.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.1
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• pp.3-14
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• 2020

Dormitories of Korean university are planned to pursue qualitative growth after a period of quantitative growth in the 1970s. However, since the 1990s, the physical plan for qualitative growth has not changed significantly and the effects of these changes on dormitory residents has not been verified. The purpose of this study is to identify the environmental factors influencing dormitory life adaptation and to provide a basis for qualitative growth of university dormitories to help dormitory residents adapt to the environment. The research was conducted in three stages. First, the elements of the residential environment of the dormitory complex, which is an independent variable, were derived. The dormitory life adaptation scale was developed to measure the dependent variable. Secondly, a questionnaire survey was conducted to obtain the environmental factors of current dormitory and previous residence and three elements of dormitory life adaptation; 'acceptance of change', 'familiarity', and 'anxiety'. Third, statistical analysis was conducted to determine whether each factor influenced dormitory life adaptation.

• Journal of Environmental Science International
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• v.30 no.6
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• pp.441-454
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• 2021

This study intended to propose an improvement plan to improve user satisfaction by establishing a park and green space masterplan by comparing its current status and surveying the residents' perception of green park services in two regions. The study results showed that the residents are aware of the physical and qualitative aspects of the green park environment. In addition, the quality level of the green park that people may actually use in everyday life was considered a factor for evaluation of satisfaction. In addition, it was found that the residents, who are actual users of the green park services, evaluated the satisfaction of use considering the qualitative characteristics of the green park, such as 'quality of green park' and 'availability of green park.' As a result, efforts are required to create and improve the quality of green parks efficiently based on establishing qualitative indicators, a survey of residents' perception, and quantitative analysis to develop policy directions and guidelines of the park and green space masterplan.

• Korean Institute of Interior Design Journal
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• no.26
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• pp.57-63
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• 2001

The aim of this study is to measure sensitivity reaction of human being with a physical properties of color and average size of particle for building materials and predict the influence of color and average size of particle in evaluation of building materials. As a results, 1) In results of qualitative evaluation construction, all 16 adjectives were extracted by higher evaluation items and ,total 14 adjectives were extracted as evaluation adjectives except adjectives of a contrary concept in each other. 2) According to the result of factor analysis, all 4 group of $\ulcirner$potency$\lrcirner$, $\ulcirner$activity$\lrcirner$, $\ulcirner$evaluation$\lrcirner$, $\ulcirner$warmness$\lrcirner$ were extracted. In this time, $\ulcirner$potency$\lrcirner$ as the first factor indicates the most hign original value. Consequently, $\ulcirner$potency$\lrcirner$ factor have an hign influence in evaluation of building materials. 3) As a influence analysis of evaluation variable by evaluation item $\ulcirner$potency$\lrcirner$ factor have an high influence by influence of average size of a particle, $\ulcirner$activity$\lrcirner$ factor have influence hignly by influence of brightness, $\ulcirner$evaluation$\lrcirner$ factor have an hign influence by influence of average site of a particle and the hue, $\ulcirner$warmness$\lrcirner$ factor have an hign influence mainly by influence of the hue

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.11a
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• pp.33-36
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• 2000

Recently, in the shipping companies have been employing prudently in order to prevent from sea accidents occurred by human factors. Also the students of merchant marine universities are choosing prudently the shipping companies when taking a job. But many qualitative and quantitative factors are considered in decision making for the employment. FSM(Fuzzy Structural Modeling) has been widely used in modeling the system composed of such qualitative and quantitative factor. In this paper, a case study is discussed for the analysis of the consciousness of the employment of shipping companies using FSM. Also this paper proposed the planes for educating and recruitment guiding the student in maritime university.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.1142-1149
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• 2003

Various organizational factors effect successful implementation of IT enabled business transformation. Among them, the most critical success factor is deemed to overcoming change management problem. Lots of studies have been made on Implementation methodologies and business process formalizations to encourage organizational members to accept new business process changes. However, the logic or process redesign still depends on qualitative problem solving techniques mostly depending on basically human intuition such as brainstorming. cause-and-effect analysis. and so on. In this paper, we focused on developing analytic framework to design to-be business process structure. which can complement qualitative problem solving procedures. With effective use of IT as an enabler, we provide algorithmic framework applicable to designing various business process changes such as process automation, business process resequencing, and more radical process integration. The framework follows dynamic programming approach in the literature, which is based on the decision making paradigm of organizations to abstract business processes as quantitative decision models. As such, our research ran fill the gap of limited development of theory based analytic methodologies for business process design, by providing objective rationale to reach the consensus among the organizational members including senior management.

• Journal of Fashion Business
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• v.12 no.6
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• pp.34-45
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• 2008

This research was designed to find decision factors through color assortment planning process by Korean women's clothing merchandisers and to look for if there exists difference with American women's clothing merchandisers. A merchandise assortment is a collection of various quantities of styles, colors, sizes, and prices of related merchandise, usually grouped under one classification within a department. The subjects were 20 women's clothing merchandisers who work for clothing retail stores from 5 to 22 years in US and Korea. The authoring process was done for qualitative data analysis. The decision factors of color assortment planning were identified with four stages; information search, qualitative evaluation, quantitative evaluation, and selection. There were differences of color assortment decision factors due to different business types, business sizes, fashion-ability, sourcing ways, and merchandise turnover. Noticeable color assortment decision factor differences caused by country difference were not found except considering the target market ethnicity and skin color in US market. Korea merchandisers seem to be more sensitive to present sales data usages and spot order availability in color assortments because of more local production use than American merchandisers.