• Journal of the Korean Society of Combustion
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• v.5 no.2
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• pp.63-68
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• 2000

Combustion phenomenon in scale-downed combustor is investigated. As the combustor scale decreases surface to volume ratio increases and chamber size approaches quenching distance. As the combustor scales down surface to volume ratio increases resulting increased heat loss. And this heat loss can affect quenching and instability of the flame. To investigate this effect plastic mini combustor is made. Stoichiometricaly premixed Hydrogen / air gas is used as fuel. Initial chamber pressure and chamber size are varied and the effects are evaluated. Peak pressure decreased with the decrease in chamber height. As initial chamber pressure decreases peak pressure decreases and this change is more important than scale down effect till the chamber height of 1mm. With this result and further information following the experiments design parameter for micro engine can be established.

• The Journal of Sustainable Design and Educational Environment Research
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• v.2 no.2
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• pp.35-51
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• 2002

This study is on the architectural planning and factors for secondary schools. The methods in the approach to the results were settled. A sample of factors that affect architectural scale design were drawn from architectural design direction for a secondary school architectural scale estimation direction. These factors arc broken into primary elements and situational elements. Primary elements include students, teachers, and time. Situational elements include public use percentage, classroom percentage, unit area, coefficient of utilization, etc. The 7 architectural planning criteria to cover changes of various architectural scale design elements are the following; 1) consideration of students selection percentage, 2) consideration of the number of teachers, 3) a variety of possible classrooms, 4) organic operation, 5) efficient time management, 6) consideration of different teaching method depending on subjects, 7) coefficient of utilization with flexibility.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.2
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• pp.110-116
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• 2011

The current study investigated the friction property of angle and width effect for micro-scale grooved crosshatch pattern on SKD11 steel surface against bearing steel using pin-on-disk type. The samples fabricated by photolithography process and then these are carry out the electrochemical etching process. We discuss the friction property due to the influence of a hatched-angle and a width of groove on contact surface. We could be explained the lubrication mechanism for a Stribeck curve. So It was found that the friction coefficient depend on an angle of the crosshatch on contact surface. It was thus verified that micro-scale crosshatch grooved pattern could affect the friction reduction. Also, it is play an important a width of groove to be improved the friction property. I was found that friction property has a relationship between a width and an angle for micro-grooved pattern.

• KSTLE International Journal
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• v.6 no.2
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• pp.51-57
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• 2005

Surface texturing of tribological applications is an attractive technology of engineered surface. Therefore, reduction of friction is considered to be necessary for improved efficiency of machines. The current study investigated the potential of textured micro-scale grooves on bearing steel flat mated with pin-on-disk. We discuss reducing friction due to the influence of sliding direction at surface pattern. We can indicate lubrication mechanism as a Stribeck curve, which has a relationship between the friction coefficient and a dimensionless parameter for the lubrication condition. It was found that the friction coefficient was changed by the surface pattern and sliding direction, even when surface pattern was the same. It was thus verified that micro-scale grooves could affect the friction reduction considerably under mixed and hydrodynamic lubrication conditions. The lubrication regime influences the friction coefficient induced by the sliding direction of groove pattern. The friction coefficient depends on a combination of resistance force and hydrodynamic.

• Journal of Sensor Science and Technology
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• v.28 no.4
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• pp.246-250
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• 2019

In this study, in conjunction with a SIMULINK program based on system modeling of a voice-coil-actuator (VCA)-driven balancing scale, a proportional-integral-derivative control algorithm is implemented, and weighing characteristics are investigated through experiments and simulations. The extent to which the back electromotive force induced in the VCA-driven circuit and the magnetic damping induced by the coil wound bobbin of VCA affect the weighing speed is also investigated.

• Korean Journal of Acupuncture
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• v.24 no.2
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• pp.77-97
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• 2007

Objectives : The aim of this study is to introduce pain measurement tools that are considered suitable for clinical practice and research for Korean Medicine Doctors. Methods : We analysed some widely used and also useful pain measurement tools in terms of their methods and dimensions. Results : Diagrams, scales and questions are usually used to measure pain intensity, temporal pattern, treatment including exacerbating and/or relieving factors, pain location, pain interference, pain quality, pain affect, pain duration, pain beliefs and pain history. Specific pain measurements are also available for specific conditions such as Western Ontario and McMaster Universities Osteoarthritis Index, Oswestry Disability Index and Neck Disability Index. Conclusions : Faces Pain Rating Scale, numeric rating scale, visual analogue scale, McGill Pain Questionnaire and Brief Pain Inventory and commonly used pain measurements. Specific measurements should be considered depending on research topics.

• Korean Journal of Child Studies
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• v.37 no.6
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• pp.35-56
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• 2016

Objective: This study aimed to develop and validate the Childcare Adaptation Scale for Infants and Toddlers (CASIT), which is rated by teachers of Korean children. Methods: The participants consisted of 326 childcare teachers working with infants (ages 0-2 years). Content validity, discriminant validity, convergent validity, concurrent validity, internal consistency, inter-rater reliability, and item discrimination were examined using PASW 18.0 and AMOS 19.0. Results: The results of an exploratory factor analysis identified the 29-item scale and six dimensions of the scale, including group life adaptation, negative behaviors, positive affect, regular routines, activity/interest, and peer interaction. Convergent validity was examined via confirmatory factor analysis, average variation extracted (AVE), and construct reliability, and acceptable evidences of convergent validity was established. The scales were shown to be highly consistent internally and among raters. Also, the mean between the upper group and lower group of each item regarding item discrimination showed a significant difference. Conclusion: It was concluded that the CASIT, which is a quick and convenient tool for teachers to use, is a valid and reliable instrument.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.3
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• pp.316-325
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• 1998

The objective of this study is to investigate the role of large-scale coherent structures in a spatially developing plane mixing layers. To achieve this, we have to look into the mutual interactions between three-dimensional large-scale coherent structures and the mean flow. Our attention will be focused on the energy exchange mechanism between the various modes, and the effects of the nonlinear evolution of the phases of the interacting modes. Linear stability of the three-dimensional viscous shear layer is formulated and solved as the basis for the solution of the nonlinear formulation based on the energy method. The importance of the initial conditions that may affect the evolution of the flow has been examined. It has been numerically calculated the nonlinear effects arising from the interactions among the three-dimensional large-scale coherent structures in a spatially developing plane mixing layers. The results of this study provide useful parametric information for the control of shear layer in practical applications in the mixing and transport augmentation.

• The Research Journal of the Costume Culture
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• v.27 no.4
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• pp.323-335
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• 2019

Identifying the selection criteria of wedding planners, who are the main human resource that contribute to the overall satisfaction level of a wedding's preparation, can produce important data for the wedding industry as it faces a transition period. To develop a scale for wedding planner selection criteria, preliminary items were prepared based on in-depth interviews with an experienced wedding planner group and a comprehensive review of previous studies, such as studies on selection criteria in the wedding industry and service work similar to wedding planners and wedding planner selection criteria. The preliminary items were tested for content validity using a focus group interview, comprising people in the wedding industry, and were refined accordingly. Then, the definitive quantitative questionnaire items were developed after conducting a preliminary survey. The main survey for this study was conducted using the responses of 295 consumers taking an Internet questionnaire. Exploratory factor analysis, Cronbach's alpha, and confirmatory factor analysis were adopted to develop the scale, which was tested for convergent validity and discriminant validity. This study is academically significant in that it developed a selection criteria scale tailored to wedding planners to address an area that has not been covered in previous studies. It is recommended that future studies conduct empirical analyses using the selection criteria developed in this study to compare influential variables that could affect behavior intention.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.7
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• pp.219-229
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• 2022

This study aims to analyze the economies of scale of the cottage industry for coconut sugar production in Banyumas, Indonesia. This study applies a survey method to coconut sugar craftsmen. Data analysis was performed by regression analysis based on the Cobb-Douglas production function approach. The findings indicated that decreasing returns to scale was a problem for the domestic production of coconut sugar. These findings show that the production of coconut sugar is not very productive. Labor and financial capital inputs have a significant positive share but the resulting increase in output is less proportional than the increase in the two inputs. Social capital, experience, and education do not affect industrial performance. To increase input productivity and production efficiency, it is necessary to apply more effective production techniques and technologies to produce quality products so that the selling price can be higher. Additionally, it is required to enhance the sap's quality through its extraction methods and the regrowth of high-yielding coconut tree varieties. From the institutional aspect, the development of this industry requires stronger partnerships with related parties such as local governments, exporting companies, cooperatives, and universities through research and development.