• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.283-289
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• 2009

In level set method, material properties are made to change smoothly across an interface of two materials with different properties by introducing an interpolation or smoothing scheme. So far, the weighted arithmetic mean (WAM) method has been exclusively adopted in level set method, without complete assessment for its validity. We showed here that the weighted harmonic mean (WHM) method for rate constants of various rate processes, including viscosity, thermal conductivity, electrical conductivity, and permittivity, gives much more accurate results than the WAM method. The selection of interpolation scheme is particularly important in multi-phase electrohydrodynamic problems in which driving force for fluid flow is electrical force exerted on the phase interface. Our analysis also showed that WHM method for both electrical conductivity and permittivity gives not only more accurate, but also more physically realistic distribution of electrical force at the interface. Our arguments are confirmed by numerical simulations of drop deformation under DC electric field.

• International Journal of Concrete Structures and Materials
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• v.7 no.3
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• pp.175-182
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• 2013

A damage-based approach for the performance-based seismic assessment of reinforced concrete frame structures is proposed. A new methodology for structural damage assessment is developed that utilizes response information at the material level in each section fiber. The concept of the damage evolution is analyzed at the section level and the computed damage is calibrated with observed experimental data. The material level damage parameter is combined at the element, story and structural level through the use of weighting factors. The damage model is used to compare the performance of two typical 12-story frames that have been designed for different seismic requirements. A series of nonlinear time history analyses is carried out to extract demand measures which are then expressed as damage indices using the proposed model. A probabilistic approach is finally used to quantify the expected seismic performance of the building.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.6 s.99
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• pp.718-723
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• 2005

The purpose of this study is to present a fundamental data for evaluating aircraft noise of building site development. By the field experiments and the predicted equal noise level contours using the INM program, actual condition in the building site development arranged district was investigated. In order to get the results, Analysis of factors effected on noise level, sound level on the rate of increase to aircraft demand and difference on the aircraft noise levels according to floor level in apartment house was carried out. As a result the influence of the take-off and landing direction were appeared greatly. The influences of the height at receiving point, movement number of aircraft and increase to aircraft demand were appeared small And the influence of 1 day average WECPNL must be considered.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1490-1495
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• 2005

In this study, Model test of concrete frame structures with various shapes and locations are carried out by means of applying Peck's(1969) settlement method. The results of the model test indicated that important correlations existed between the behavior of frame structure and ground movement. Also, the damage level of frame structure closely influenced by the phase of excavation. Therefore, prediction of damage level at early phase of construction should be very precise. The damage level graph by Cording et al.(2001), the angular distortion provided gradually more serious damage to frame structures for the all cases. But the damage level graph by Burland(1997), was difficult to confirm because of very small amount of deflection ratio.

• Journal of Engineering Education Research
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• v.16 no.4
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• pp.21-29
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• 2013

Accreditation of engineering education as initiated by Accreditation Board for Engineering Education of Korea (ABEEK) centers around three key issues: program outcomes, assessment/evaluation thereof, and continuous quality improvement (CQI). Most engineering departments, however, are neither adequately familiar with nor well prepared for the issues, especially CQI. The CQI in almost all departments seems to be overly confined in individual courses and the final capstone design courses for seniors; there is no evidence that CQI is not limited to the course level but flows through all courses in the curriculum. This paper presents a sound and viable framework for CQI implementation in which course-level CQI is integrated into the department/program-level CQI.

• East Asian mathematical journal
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• v.30 no.4
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• pp.527-544
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• 2014

The purpose of this thesis is to analyze mathematical errors in descriptive problems of the Mathematics Level Assessment(MLA) which is conducted in P University. We classified mathematical errors, which are easily made in solving the descriptive problems of the MLA, into nine types as misused data, misinterpreted language, logically invalid inference, misunderstood theorem or definition, unmatched solution, technical errors, omission of solving process, ambiguous errors, and unattempted errors. With classifying the errors in nine types, we analyzed the errors of students, who are in intermediate and low level grades, by descriptive problems. On the basis of these analysis results, we suggest plans for improving the implementation of the MLA and the teaching-learning methods about College General Mathematics.

• Journal of Ocean Engineering and Technology
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• v.11 no.3
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• pp.8-19
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• 1997

In this study an adequate type of offshore structure at the Sakhalin region as cold region is proposed and its structural design results are presented based on the reliability analysis. Structural safety assessment has been carried out for the proposed offshore structure at the Sakhalin area as designed by the reliability method. And a rational design procedure is presented based on the reliability analysis. Followings are drawn through the present study : - Four colum TLP structure is proposed as an adequate offshore structure type at the cold region like the Sakhalin region and the reliability-based structural design results are presented. It is seen that the proposed type is a more adequate and economic than the fixed type. - Safety assessment of the proposed structure applying the extended incremental load method is performed. - Referring the allowable safety level for offshore structures it has been found present TLP structure has sufficient structural safety at the system level as well as at the component level.

• Journal of Information Technology Services
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• v.8 no.3
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• pp.159-169
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• 2009

The issue of method of software testing process implementation has recently been in the spotlight in korea and some vendor make every effort to improve the software testing process through the evaluation of TMMi. The level of software process is at initial level, nevertheless, so the high quality of software is not guaranteed. This paper apply to the TMMi Level2 Assessment criteria of Automobile control software testing process. The test policy and strategy, test planning, test monitoring and control, test design and execution, test environment goal. The result need to emerge development process connection on the test policy and strategy process, test planning process etc. Also, the study analyzed the infra structure to reach the repeated level via key process area. As the result the process implementation in organization suggests the policy development and the implementation activity. Finally, the practical can refer to this paper in order to implementation the software testing process.

• Journal of The Korean Association For Science Education
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• v.22 no.2
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• pp.230-239
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• 2002

This study was performed to analyze the secondary students' perceptions and self-efficacy of performance assessments in the science subject. The data was obtained from 236 middle school students and 222 high school students in seoul. The students had generally proper understanding about characteristics of performance assessment which include purposes of assessment and differences from other conventional achievement assessments. They responded that the performance assessments were not useful in their science learning and developing their potential abilities. They were not satisfied with reliability and validity of the performance assessments. The middle school students more positively responded than high school students regarding the reliability of the scoring system and the originality of the evaluating materials. The female students more positively thought than males about the reliability of assessment and the usefulness for learning science. The students' self-efficacy level of performance assessment were not low in comparison with another existing assessments. They had high level of self-efficacy in understanding of experimental procedures, and utilizing of experimental apparatuses, but had low level of self-efficacy in understanding purposes of experiments or issues of discussions, processing of experimental results, answering of problems in experimental discussions. The female students' self-efficacy of performance assessment were higher than male students'. There was statistically correlated with females' scores and their level of self-efficacy of performance assessment.

• Journal of Advanced Navigation Technology
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• v.18 no.6
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• pp.562-568
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• 2014

This study is safety assessment standard for advanced surface movement guidance control system (A-SMGCS) and case study of the past research project. A-SMGCS providing routing, guidance and surveillance for the control of aircraft and vehicles in order to maintain the declared surface movement rate under all weather conditions within the aerodrome visibility operational level while maintaining the required level of safety. Recently, in korea and europe are developing A-SMGCS system for the safety control of the airport movement area. In safety oriented industry such as aviation that it is necessary to verify and ensure for operating system. In this case study, analysis of safety assessment standard for verified A-SMGCS target level of safety (TLS) and previous developed A-SMGCS research project.