• Earthquakes and Structures
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• v.11 no.5
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• pp.905-924
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• 2016

Several two-dimensional analytical beam column joint models with varying complexities have been proposed in quantifying joint flexibility during seismic vulnerability assessment of non-ductile reinforced concrete (RC) frames. Notable models are the single component rotational spring element and the super element joint model that can effectively capture the governing inelastic mechanisms under severe ground motions. Even though both models have been extensively calibrated and verified using quasi-static test of joint sub-assemblages, a comparative study of the inelastic seismic responses under nonlinear time history analysis (NTHA) of RC frames has not been thoroughly evaluated. This study employs three hypothetical case study RC frames subjected to increasing ground motion intensities to study their inherent variations. Results indicate that the super element joint model overestimates the transient drift ratio at the first story and becomes highly un-conservative by under-predicting the drift ratios at the roof level when compared to the single-component model and the conventional rigid joint assumption. In addition, between these story levels, a decline in the drift ratios is observed as the story level increased. However, from this limited study, there is no consistent evidence to suggest that care should be taken in selecting either a single or multi component joint model for seismic risk assessment of buildings when a global demand measure such as maximum inter-storey drift is employed in the seismic assessment framework.

• Journal of Soil and Groundwater Environment
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• v.20 no.3
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• pp.15-24
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• 2015

The soil ecosystem is a complex system performing particularly complicated and varied functions, such as providing a habitat for organisms, acting as a medium for plant cultivation and growth, and functioning as a buffer against external materials in the environment. To assess whether these important functions of the soil ecosystem are executed appropriately, the concept of soil ecosystem health has been introduced, which is defined as the ability to perform the specific functions of the soil ecosystem. Understanding soil properties and soil indicators related to soil functions is essential to assess the soil health. In this study, systems, the indicators, and evaluation factors for assessing soil ecosystem health employed in a number of countries were investigated and discussed. In particular, it is necessary to introduce a technique for the evaluation of soil ecosystem health in Korea and to develop techniques and indicators appropriate to the soil ecosystem and status in Korea.

• Journal of Environmental Impact Assessment
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• v.18 no.5
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• pp.313-319
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• 2009

A complex maritime resort combined marina and with course of Korea is required to improve international tourism competitiveness by taking advantage of her environmental favorable circumstances. The development of tourism, however, is focused on land-oriented that incurred lower tourism efficiency and international tourism competitiveness. In addition, the regulation of "Preliminary environmental assessment for golf courses" by the Ministry of Environment is emphasized on land geography and geology that can cause damage of tourist attractions in an island region. In particular, the development of 6th or 7th ridges in mountainous island region within 2km from the sea, that holds scenic and academic value, can go against environment-friendly by geographical and geological damage. According to the regulation for consultation for golf courses and forestry is to preserve regional ecosystem over 6th ridge, but it cannot be applicable to island region because that can form excessive slopes where marine ecosystem is required to be maintained. It, therefore, can be desirable that the development of over 6th ridge in an island region. It is suggested that continuous comparative studies of geographical and geological characteristics between land and island region will be carried on to establish feasible and reasonable development model so that balanced development of land and island, and versatile international environment-friendly maritime resort can be achieved and developed.

• Proceedings of the Korea Contents Association Conference
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• 2016.05a
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• pp.383-384
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• 2016

The Special Needs Education Assessment Tool (SNEAT) were verified of reliability and validity. However, the reliability and validity has been verified is only Okinawa Prefecture, the national data has not been analyzed. Therefore, this study aimed to verify the reliability and construct validity of SNEAT in Miyagi Prefecture as part of the national survey. SNEAT using 55 children collected from the classes on independent activities of daily living for children with disabilities in Miyagi Prefecture between November and December 2015. Survey data were collected in a longitudinal prospective cohort study. The reliability of SNEAT was verified via the internal consistency method; the coefficient of Cronbach's ${\alpha}$ were over 0.7. The validity of SNEAT was also verified via the latent growth curve model. SNEAT is valid based on its goodness-of-fit values obtained using the latent growth curve model, where the values of comparative fit index (0.997), tucker-lewis index (0.996) and root mean square error of approximation (0.025) were within the goodness-of-fit range. These results indicate that SNEAT has high reliability and construct validity.

• Journal of Environmental Science International
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• v.16 no.6
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• pp.715-723
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• 2007

The air pollutant emission is mainly caused by line sources in urban area. For example, the annually totaled air pollutant emission is known to consist of about 80% of line sources in Daegu. Hence, the appropriate assessment on the air pollutants of line sources is very important for the atmospheric environmental management in urban area. In this study, we made a comparative study to evaluate suitable dispersion model for estimating the air pollution from line sources. Two air pollution dispersion models, ISCST3 and CALINE4 were the subject of this study. The results were as follows; In the assessment of air pollution model, ISCST3 was found to have 4 times higher concentration than CALINE4. In addition, actual data obtained by measurement and estimated values by CALINE4 were generally identical. The air pollution assessment based on ISC3 model produced significantly lower values than actual data. The air pollution levels estimated by ISCST3 were very low in comparison with the observational values.

• The Mathematical Education
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• v.49 no.4
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• pp.523-540
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• 2010

The purpose of the study were to analyze MathThematics textbooks and Korean middle school mathematics and to investigate the difference among the textbooks in the view of mathematical communication. According to the results, the textbook developers made a variety of efforts to develope students' mathematical communication ability. Students were encouraged to communicate with others about their mathematical ideas or problem solving processes in words or writing by means of discussion, oral report, presentation, journal, etc. MathThematics textbooks provided student self-assessment opportunity to improve student performance in problem solving, reasoning, and communication. In communication assessment, students can assess their use of mathematical vocabulary, notation, and symbols, the use of graphs, tables, models, diagrams and equation to solve problem and their presentation skills. The assessment activities would make a positive impact on the development of students' mathematical communication ability. MathThematics textbooks provided a variety of problem situation including history, science, sports, culture, art, and real world as a topic for communication, however, the researcher found that some of Korean textbooks depends heavily on mathematical problem situations.

• The Journal of Asian Finance, Economics and Business
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• v.2 no.2
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• pp.19-25
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• 2015

This research is aimed the furthest development of the conception of Human capital formation. The study made on the base of methods of scientific classification and systematization; dialectical method and the method of scientific abstraction, systematic and comparative analysis; expert assessment and ratings. Formation of the competitive human capital is one of the most important goals of modern development of Kazakhstan in condition of the innovative economy construction. In this context the necessity of formation and development of the effective human capital considerably increases. Realization of this requires definition of a technique of measurement of its cost as well. The authors attempt to calculate the value of human capital for Kazakhstan during independency time. In order to determine the methods of its quantitative and qualitative assessment different methodological ways for human capital research are studied. On the basis of the study, it was revealed that formation of the competitive human capital can't be considered in a separation from development and modernization of system of quality education, improvement of the employment sphere, worthy payment for work.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.1
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• pp.165-173
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• 2023

Various linear system solvers with multi-physics analysis schemes are compared focusing on the near-field region considering thermal-hydraulic-chemical (THC) coupled multi-physics phenomena. APro, developed at KAERI for total system performance assessment (TSPA), performs a finite element analysis with COMSOL, for which the various combinations of linear system solvers and multi-physics analysis schemes should to be compared. The KBS-3 type disposal system proposed by Sweden is set as the target system and the near-field region, which accounts for most of the computational burden is considered. For comparison of numerical analysis methods, the computing time and memory requirement are the main concerns and thus the simulation time is set up to one year. With a single deposition hole problem, PARDISO and GMRES-SSOR are selected as representative direct and iterative solvers respectively. The performance of representative linear system solvers is then examined through a problem with an increasing number of deposition holes and the GMRES-SSOR solver with a segregated scheme shows the best performance with respect to the computing time and memory requirement. The results of the comparative analysis are expected to provide a good guideline to choose better numerical analysis methods for TSPA.

• Journal of the Korean Society of Safety
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• v.38 no.6
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• pp.72-78
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• 2023

The purpose of this paper is to derive a quantified approach for Operator Manual Actions (OMAs) based on the existing fire Human Reliability Analysis (HRA) methodology developed by the Korea Atomic Energy Research Institute (KAERI). The existing fire HRA method was reviewed, and supplementary considerations for OMA quantification were established through a comparative analysis with NUREG-1852 criteria and the review of the existing literature. The OMA quantification approach involves a timeline that considers the occurrence of Multiple Spurious Operations (MSOs) during a Main Control Room Abandonment (MCRA) determination and movement towards the Remote Shutdown Panel (RSP) in the event of a Main Control Room (MCR) fire. The derived failure probability of an OMA from the approach proposed in this paper is expected to enhance the understanding of its reliability. Therefore, it allows moving beyond the deterministic classification of "reliable" or "unreliable" in NUREG-1852. Also, in the event of a nuclear power plant fire where multiple OMAs are required within a critical time range, it is anticipated that the OMA failure probability could serve as a criterion for prioritizing OMAs and determining their order of importance.

• Structural Engineering and Mechanics
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• v.89 no.5
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• pp.491-505
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• 2024

This study evaluates the seismic performance of a premodern six story reinforced concrete building typology designed during the communism period of Albania and build throughout the country. During the November 26, 2019 Earthquake in Albania, the most affected reinforced concrete buildings were among the old templates, lacking shear walls and inadequate reinforcement details which suffer from concrete aging. The mathematical model of the selected building is done in the environments of ZeusNL software, developed especially for earthquake engineering applications. The capacity curve of the structure is gained using the conventional static nonlinear analysis. On the other hand, the demand estimation is utilized using one of the recent methods known as Incremental Dynamic Analysis with a set of 18 ground motion records. The limit states in both curves are defined based on the modern guidelines. For the pushover, immediate occupancy (IO), life safety (LS) and collapse prevention (CP) are plotted in the same graph with capacity curve. Furthermore, on each IDA derived, the IO, CP and global instability (GI) are determined. Moreover, the IDA fractiles are generated as suggested by the literature, 16%, 50% (median) and 84%. In addition, the comparative assessment of the IDA median with capacity curve shows good correlation points. Lastly, this study shows the approach of determination of LS in IDA fractiles for further vulnerability assessment based on the local seismic hazard map with 95 and 475 return period.