• Journal of Korean Society of Steel Construction
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• v.21 no.3
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• pp.321-330
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• 2009

This paper presents numerical analysis results for the lateral-torsional buckling (LTB) strength of steel I-girder bridges. Current Korean and AASHTO design specifications for LTB consider the buckling strength of a single girder with both its ends constrained. The I-girder bridges are composed of more than one girder, and the girders are interconnected with intermediate cross-beams or cross-frames. Therefore, it should be required to evaluate the effects of cross-beam stiffness and the interactionof girders on LTB strength. It is also necessary to consider the effects of transverse web stiffeners on LTB strength. By considering these parameters, a series of four-girder systemswere numerically modeled using 3D shell elements to estimate the LTB strength while considering initial imperfections and residual stresses.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1346-1350
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• 2009

SWAT 모형에서는 중간유출, 침루, 토양 증발, 식물에 의한 증산 등의 수문과정을 모사하기 위해서 토양 수대를 토양의 물리적 특성에 따라 몇 개의 층으로 구분하고, 각 층별로 순차적으로 각 성분량을 계산한다. 이 때 지표유출로 인한 영양물질 이송이 기작되는 영역을 설정하기 위해서 사용자가 입력한 첫 번째 토양층을 강제적으로 둘로 구분하여 상부 10mm의 새로운 토양층이 자동 생성되도록 알고리즘화되어 있다. 그러나, 동일한 토양 특성을 가진 층을 임의적으로 둘로 구분하는 것은 토양 물리적 관점에서 보면 적절하지 않으며, 또한 생성된 매우 얇은 상부 10 mm 토양층으로 인해서 포장용수량을 초과하는 과잉수가 커서 경사가 급한 유역이나 토양층의 투수성이 매우 큰 지역에 모형을 적용할 경우에는 중간유출량이 비현실적으로 크게 계산되는 문제를 수반한다. 따라서 본 연구에서는 중간유출이 크게 계산되는 문제점을 해결하고 토양층내의 수분 거동을 보다 현실적으로 모사하기 위해서 합체-분리 (combining-partitioning) 방식의 토양층 구조화 기법을 고안하고 SWAT의 지표하 유출 계산 모듈에 새롭게 추가하였다. 모형 개선이 수문 및 수질 성분 모의에 미치는 영향을 평가하기 위해서 충주댐 상류유역을 대상으로 모델링을 수행하고 상대비교를 한 결과, 토양수분, 중간 및 지하수유출, 인 순환에 미치는 영향이 가장 큰 것으로 분석되었다.

• Geotechnical Engineering
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• v.12 no.4
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• pp.101-114
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• 1996

In this study, the characteristics of bearing capacity and deformation of intermediate soils are investigated through centrifuge tests. The experimental parameters are footing width, initial stress condition of soils and relative loading rate defined relationship of loading rate and permeability of soils. It is examined that loading rate influences on the bearing capacities and deformations. Based on the test results, some problem of existing specification are introduced in the view of related loading rates and load intensities. Especially it is showed that load intensities magnitude rlre reversed in the same settlement ratio(s/B(%)), due to partial drained effect as well as loading rates in undrained con dition based on the excess pore pressure and deformations measured under loading.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.4
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• pp.337-346
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• 2020

Traffic jam and congestion in urban areas has caused the need to improve the utility of underground space. In response, research on underground structures is increasingly being conducted. Notably, a double-deck tunnel is one of the most widely used of all those underground structures. This double-deck tunnel is separated by the middle slab into the upper and lower roadways. Both vehicle load and earthquake load cause the middle slab to exhibit dynamic behavior. Earthquake-related response characteristics, in particular, are highly complex and difficult to interpret in a theoretical context, and thus experimental research is required. The aim of the present study is to assess the stability of a double-deck tunnel's middle slab of the Collapse Prevention Level and Seismic Category 1 with regard to the presence of vibration-damping Rubber Bearings. In vibration table tests, the ratio of similitude was set to 1/4. Linings and vibrating platforms were fixed during scaled model tests to represent the integrated behavior of the ground and the applied models. In doing so, it was possible to minimize relative behavior. The standard TBM cross-section for the virtual double-deck tunnel was selected as a test subject. The level of ground motion exerted on the bedrock was set to 0.154 g (artificial seismic wave, Collapse Prevention Level and Seismic Category 1). A seismic wave with the maximum acceleration of 0.154 g was applied to the vibration table input (bedrock) to analyze resultant amplification in the models. As a result, the seismic stability of the middle slab was evaluated and analyzed with respect to the presence of vibration-damping rubber bearings. It was confirmed that the presence of vibration-damping rubber bearings improved its earthquake acceleration damping performance by up to 40%.

• 한국사회복지학회:학술대회논문집
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• 1994.11a
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• pp.381-392
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• 1994

• Magazine of the Korean Society of Agricultural Engineers
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• v.61 no.3
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• pp.7-16
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• 2019

• Korean Journal of Comparative Education
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• v.24 no.3
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• pp.245-265
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• 2014

The purpose of this research is to find the features of HLC institutional accreditation model and the implication on the second period institutional accreditation of Korea. This research focus on accreditation model, accreditation period, comprehensive evaluation, criteria, decision making for accreditation status and accreditation supporting system. This research draws following suggestions to the second period institutional accreditation of Korea. 1. The institutional accreditation should apply various accreditation models according to the features of institute. 2. The institutional accreditation should focus on the autonomous quality improvement of institute with the quality assurance. 3. The quantitative evaluation should be reduced and qualitative evaluation based on mission and objects should be reinforced. 4. The interim evaluation should be strictly enforced for quality improvement. 5. The government should enlarge reflection the results of accreditation on financial aid to universities. 6. The web-based accreditation supporting system interworking with "Higher Education in Korea" service is needed.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.759-774
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• 2018

This study was conducted to establish scores according to the importance levels of each HACCP evaluation item in cattle farm. The importance levels and score of each HACCP evaluation item was derived through the non-compliance rate and severity levels of hazard. In order to change the score criteria according to the importance of each HACCP evaluation item, we analyzed the importance of each HACCP evaluation item by using the portfolio mapping method according to the occurrence frequency and severity levels of hazard. The scores were classified into 3 point, 2 point, and 1 point, respectively, by classifying the importance of each category as 'high', 'middle' and 'lower'. Accordingly, we have established a now scoring system of each HACCP evaluation item through this study. Through the result of this study, the objectivity of the comparative evaluation was verified by implementing the currently used HACCP evaluation item to the cattle farm. In conclusion, Implementation of the result of this study to cattle farm may help to increase the objectivity and also improve more safety and hygienic cattle management and raw milk production.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.860-862
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• 2003

기존의 수행평가는 교사 본연의 업무인 교육과 연구 활동에 지장을 초래할 만큼 과중한 업무부담이 발행하는 문제점이 있다. 본 논문에서는 이러한 문제점을 해결하고 보다 효율적인 수행평가를 처리하기 위하여 교무업무지원시스템과 연계한 수행평가시스템을 구현한다. 세부적으로 수행평가 업무처리 과정에서 발생하는 중복 입력 작업을 데이터베이스를 연계하여 최소화하고, 수행평가 계획에서부터 최종 출력물까지 일괄처리하여 오류 발생 가능성이나 중간입력 확인 과정을 생략함으로써 교사의 업무 부담을 경감시켜 교사 본연의 가르치는 업무에 보다 충실할 수 있는 시스템 개발을 목표로 하였다.

• Journal of the Korean Society for Library and Information Science
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• v.52 no.3
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• pp.91-119
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• 2018

The primary focus of this study was on the development of a leadership scale to measure the leadership capacities of university library middle managers. The study included the following research activities. Firstly, broad and narrow scopes were determined and their corresponding questions were selected to develop a leadership scale of university middle managers by analyzing the previous related research findings. Secondly, the scopes and the questions were revised through the Delphi survey method, Thirdly, a survey was conducted to develop a simplified model of the leadership scale. The research outcomes led to three types of leadership scale of the university library middle manager. This study identified the leadership factors of middle managers in the university libraries. The resulting developed leadership scale should serve as the basic information for the existing middle managers' leadership capacity development.