• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.161-172
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• 2008

The level of service (LOS) evaluation method of the Highway Capacity Manual (HCM) is limited to intersections with pre-timed signal operation, while advanced real-time traffic control systems have been expending in the field. This paper proposes a preliminary framework for LOS analysis at isolated intersections controlled by COSMOS, the real-time traffic control systems robustly utilizing the degree of saturation as basic inputs. The proposed LOS evaluation framework was devised with a pilot model developed to estimate the average cycle length and green times of COSMOS. The validation test showed that the proposed framework was able to accurately project the LOS, which was separately evaluated based upon field data.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.10
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• pp.1866-1872
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• 2007

Information system contains various components, md these components can be categorized into some types. When preparing security level management activity, it is most important to define the target of management activity. And after deciding these targets, security level management activity can be started. This paper defines management targets by dividing information system into some parts, and these targets can be managed variously according to operation environments and characteristics. By doing so, security level management activity can be processed easily.

• Journal of Science Education
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• v.36 no.2
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• pp.216-234
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• 2012

This study examined the characteristics of verbal interactions presented in TS activities with different tasks' openness levels by the cognitive levels of students through the implementation of TS program to 14 fifth graders in gifted class. Results of this study revealed that the open-type TS activities showed higher percentages of verbal interactions than the guiding-type TS activities showed and that the higher the open level of tasks was, the more high-level verbal interactions occurred. These results were showed in almost all subcomponents of verbal interactions. The results according to the students' cognitive levels showed that the higher the cognitive level of students was, higher frequency of interactions, high-level verbal interactions and a variety of verbal interactions occurred. The influence of both cognitive level of students and the task's openness on verbal interactions among students seemed to be interactive, however. In guiding-type activities, the percentage of high-level verbal interactions was not high although the cognitive level of students was high. And students in low level of cognition showed far lower frequency of interactions and their percentage of high-level verbal interactions was low even though the openness of the tasks was high. The results of this study meant that although open-type activities drew higher level verbal interactions by stimulating students' thought, the effects would be limited owing to their low cognitive level. Based on these findings, an implication was suggested that it is important to design instructional strategies and adjust openness level of TS activities to students' cognitive level so as to stimulate the thinking of students in lower cognitive level and to highten their engagement in activities.

• Korea journal of population studies
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• v.26 no.1
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• pp.79-113
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• 2003

This study is intended to explore an income level necessart for the old-age by income Status. Firstly, it is verified whether there is significant difference between old-age and working age or not. Secondly, if their difference is found, it will be identified that it is determined by certain factors. Thirdly, it is brought out needful income level for the old-age living through analysing old-age consumption expenditure level over working age. The results in this research are as follows. Firstly, there is a significant difference between old-age and working age. Secondly, the major factors which generated difference between old-age and working age consumption expenditure are income, household size, and age. Thirdly, the income level necessary for oldage living is on average 61 %. By income status, it is 90-100% for low income status, 60-70% for middle income status, 50-60% for high income status.

• Journal of Gifted/Talented Education
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• v.21 no.2
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• pp.287-307
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• 2011

The purpose of this study is to investigate levels of mathematically gifted students' understanding of statistical samples through comparison with non-gifted students. For this purpose, rubric for understanding of samples was developed based on the students' responses to tasks: no recognition of a part of population (level 0), consideration of samples as subsets of population (level 1), consideration of samples as a quasi-proportional, small-scale version of population (level 2), recognition of the importance of unbiased samples (level 3), and recognition of the effect of random sampling (level 4). Based on the rubric, levels of each student's understanding of samples were identified. t tests were conducted to test for statistically significant differences between mathematically gifted students and non-gifted students. For both of elementary and middle school graders, the t tests show that there is a statistically significant difference between mathematically gifted students and non-gifted students. Table of frequencies of each level, however, shows that levels of mathematically gifted students' understanding of samples were not distributed at the high levels but were overlapped with levels of non-gifted students' understanding of samples.

• Journal of Elementary Mathematics Education in Korea
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• v.21 no.4
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• pp.575-598
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• 2017

This study aims to explore the level-specific characteristics of arithmetical thinking based on the arithmetical thinking factors and develop an arithmetical thinking level test that can identify students' arithmetical thinking levels by specifying the levels of arithmetical thinking based on the factors. In order to solve the research problems, we categorized the arithmetical thinking factors into 1~4 levels based on the literature review and constructed items of the arithmetical thinking level test considering both content and process based on the arithmetical thinking factors and the level-specific characteristics of the arithmetical thinking which conformed to the Guttman scale. To investigate the adequacy of the analysis of the arithmetical thinking levels, we reanalyzed the level-specific characteristics of the arithmetical thinking by checking that it matched the factors classified to the test developed by the Guttman scale. From the results of this research, the following conclusions were drawn. First, the arithmetical thinking factors are categorized into four levels which have different characteristics. Second, the arithmetical thinking level test of this study was developed satisfying the Guttman scale and it reflects the level-specific characteristics of the arithmetical thinking levels from 1 to 4. It is possible to determine the students' arithmetical thinking level using this test. Third, according to the results of the final application of the arithmetical thinking level test for 5th and 6th graders, teachers should provide more abundant learning experiences related to the relation level (the level 3) and the application level (the level 4) to increase students' arithmetical thinking level.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.1
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• pp.17-26
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• 2008

The 1st order level network of Korea was adjusted simultaneously in 1987. After that, the 1 st order level network of Korea was adjusted simultaneously by National Geographic Information Institute in 2006. The levelling data were acquired by digital level with invar staff from 2001 through 2006. The 1st order level network consists of 36 level lines. Among them, 34 level lines comprise 11 level loops. Among 36 level lines, 4 level lines have fore & back error larger than the regulations for the 1st order levelling of NGII, Korea. Also, the closing error of 3 loops of level network exceed the regulation for the 1st order levelling of NGII. The standard error of fore and back leveling between bench marks(${\eta}_1$) are distributed between 0.2 $mm/{\surd}km$ and 1.7 $mm/{\surd}km$. The standard error of loop closing(${\eta}_2$) is 2.0 $mm/{\surd}km$. This result means that the 1st order level network of Korea qualifies for the high precision leveling defined by International Geodetic Association in 1948. As the result of the 1st order level network adjustment, the reference standard error($\hat{{\sigma}_0}$) of the level network was 1.8 $mm/{\surd}km$, which is twice as good as that of the 1st adjustment of level networks in 1987.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.3
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• pp.173-184
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• 2023

Presently, the general seismic fragility evaluation method for a bridge system composed of member elements with different nonlinear behaviors against strong earthquakes has been to evaluate at the element-level. This study aims to develop a system-level seismic fragility evaluation method that represents a structural system. Because the seismic behavior of bridges is generally divided into transverse and longitudinal directions, this study evaluated the system-level seismic fragility in both directions separately. The element-level seismic fragility evaluation in the longitudinal direction was performed for piers, bridge bearings, pounding, abutments, and unseating. Because pounding, abutment, and unseating do not affect the transverse directional damages, the element-level seismic fragility evaluation was limited to piers and bridge bearings. Seismic analysis using nonlinear models of various structural members was performed using the OpenSEES program. System-level seismic fragility was evaluated assuming that damage between element-levels was serially connected. Pier damage was identified to have a dominant effect on system-level seismic fragility than other element-level damages. In other words, the most vulnerable element-level seismic fragility has the most dominant effect on the system-level seismic fragility.

• Journal of the Korean association of regional geographers
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• v.11 no.5
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• pp.474-487
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• 2005

This paper aims to provide empirical evidence required to describe the level of achievement by analyzing students' item response in NAEP implemented in the United States in 2001. The geography assessment in the NAEP is aimed to test students of 4th, 8th, and 12th grades, and consists of content dimension and cognitive dimension, The former includes 'space and place' 'environment and society' and 'spatial dynamics and connections,' and the latter includes 'knowing' 'understanding' and 'applying,' The level of achievement is defined as three levels for each grade: Basic, Proficient, and Advanced. In this paper, descriptions of achievement is derived inductively from an analysis of student's responses to the items which were selected by using item-mapping method. As a result, there is a great difference between the level of achievement derived empirically from students' response and the level of achievement designed principally suggested by the expert committee. The former could have a contribution to the improvement in geography curriculum.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4496-4505
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• 2012

As the result of this study, total 27 core competencies are developed and categorized into four competence groups; common competence group, teamwork formation competence group, data-processing and analysis group and resource management and application competence group. The result of diagnosing of competency level, the required level of competencies were more higher than possessed level. This result supports that it is essential to raise the competency level of employees entirely through the education programs. The data analysis with two independent variances, rank and type of occupation, shows the significant difference between the required and current competency level in terms of ranks, staff, senior and principle. Therefore, it is necessary to provide a differentiated educational programs considering ranks.