• Structural Engineering and Mechanics
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• v.59 no.4
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• pp.683-701
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• 2016

Safety is the prime concern for a high-speed railway bridge, especially when it is subjected to a collision. In this paper, an analysis framework for the dynamic responses of train-bridge systems under collision load is established. A multi-body dynamics model is employed to represent the moving vehicle, the modal decomposition method is adopted to describe the bridge structure, and the time history of a collision load is used as the external load on the train-bridge system. A (180+216+180) m continuous steel trussed-arch bridge is considered as an illustrative case study. With the vessel collision acting on the pier, the displacements and accelerations at the pier-top and the mid-span of the bridge are calculated when a CRH2 high-speed train running through the bridge, and the influence of bridge vibration on the running safety indices of the train, including derailment factors, offload factors and lateral wheel/rail forces, are analyzed. The results demonstrate that under the vessel collision load, the dynamic responses of the bridge are greatly enlarged, threatening the running safety of high-speed train on the bridge, which is affected by both the collision intensity and the train speed.

• Biomolecules & Therapeutics
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• v.22 no.4
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• pp.334-340
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• 2014

In this study, 23 oleanane-type triterpenoid saponins were isolated from a methanol extract of the roots of Pulsatilla koreana. The NF-${\kappa}B$ inhibitory activity of the isolated compounds was measured in $TNF{\alpha}$-treated HepG2 cells using a luciferase reporter system. Compounds 19-23 inhibited $TNF{\alpha}$-stimulated NF-${\kappa}B$ activation in a dose-dependent manner, with $IC_{50}$ values ranging from $0.75-8.30{\mu}M$. Compounds 19 and 20 also inhibited the $TNF{\alpha}$-induced expression of iNOS and ICAM-1 mRNA. Moreover, effect of the isolated compounds on PPARs transcriptional activity was assessed. Compounds 7-11 and 19-23 activated PPARs the transcriptional activity significantly in a dose-dependent manner, with $EC_{50}$ values ranging from $0.9-10.8{\mu}M$. These results suggest the presence of potent anti-inflammatory components in P. koreana, and will facilitate the development of novel anti-inflammatory agents.

• Korean journal of food and cookery science
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• v.29 no.3
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• pp.275-281
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• 2013

This study was performed to evaluate the quality characteristics and antioxidative activities of cookies prepared with different amounts of purple sweet potato powder. Moisture and crude ash contents were lowest in the control group followed in order by the 10%, 20%, and 30% purple sweet potato powder addition groups. The lightness and yellowness values measured by Hunter color system decreased based on the amount of purple sweet potato powder concentration added to cookies. The total phenolic compound and anthocyanin contents were the highest in 30% purple sweet potato powder added cookies. The DPPH radical scavenging activity of 30% purple sweet potato powder added cookies showed the highest values among groups. In the sensory evaluation, the scores for taste, texture and overall preference were significantly highest in cookies with 10% and 20% purple sweet potato powder. Considering the scores of antioxidant activity and sensory evaluation, the concentration of between 10% and 20% addition of purple sweet potato powder would be ideal for development of functional cookies.

• Structural Engineering and Mechanics
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• v.54 no.2
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• pp.305-317
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• 2015

Optimal sensor placement (OSP) is an integral component in the design of an effective structural health monitoring (SHM) system. This paper describes the implementation of a novel collaborative-climb monkey algorithm (CMA), which combines the artificial fish swarm algorithm (AFSA) with the monkey algorithm (MA), as a strategy for the optimal placement of a predefined number of sensors. Different from the original MA, the dual-structure coding method is adopted for the representation of design variables. The collaborative-climb process that can make the full use of the monkeys' experiences to guide the movement is proposed and incorporated in the CMA to speed up the search efficiency of the algorithm. The effectiveness of the proposed algorithm is demonstrated by a numerical example with a high-rise structure. The results show that the proposed CMA algorithm can provide a robust design for sensor networks, which exhibits superior convergence characteristics when compared to the original MA using the dual-structure coding method.

• Structural Monitoring and Maintenance
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• v.4 no.1
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• pp.33-52
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• 2017

A cantilever beam with a breathing crack is studied to improve the breathing crack identification sensitivity by the parametric optimization of sample entropy and wavelet transformation. Crack breathing is a special bi-linear phenomenon experienced by fatigue cracks which are under dynamic loadings. Entropy is a measure, which can quantify the complexity or irregularity in system dynamics, and hence employed to quantify the bi-linearity/irregularity of the vibration response, which is induced by the breathing phenomenon of a fatigue crack. To improve the sensitivity of entropy measurement for crack identification, wavelet transformation is merged with entropy. The crack identification is studied under different sinusoidal excitation frequencies of the cantilever beam. It is found that, for the excitation frequencies close to the first modal frequency of the beam structure, the method is capable of detecting only 22% of the crack depth percentage ratio with respect to the thickness of the beam. Using parametric optimization of sample entropy and wavelet transformation, this crack identification sensitivity is improved up to 8%. The experimental studies are carried out, and experimental results successfully validate the numerical parametric optimization process.

• Korean Journal of Human Ecology
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• v.18 no.3
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• pp.769-773
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• 2009

The purpose of this study is to examine the food consumption behavior, the attitudes to food sanitation and the HACCP(?) knowledge of college students. Questionnaires were collected from 130 students in Daejeon University. The subjects mainly purchased their food at big discount stores and thought of expiration date as a most important factor considered. When purchasing the grocery, female students seldom took the convenience cooking into consideration, however, 10.3% of male students concerned it(p<0.05). In subjects' knowledge of food hygiene, the average score was 16.21 and in their performance(p<0.05)of it, the average score was 11.14. Especially in their knowledge of separate food storage, the average point was 5.03 and in their performance of it(p<0.05), the average point was 2.84. 72% of respondents had ever experienced food sanitation education. Of students who answered that food sanitation education was very helpful, the number of students living in university dormitory or boarding houses was as much again as that of students living in their own places. 82.2% of students did not know about HACCP system. They wanted to know 'the meaning(43%)', 'the necessity' (19.6%), 'the advantage(9.3%)' of HACCP and 'the kinds of food products adopting HACCP(28%)'.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.1319-1322
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• 2005

최근 컴퓨터 기술의 발달로 공공 분야에서 구조물 감시 시스템의 중요성이 대두 되고 있다. 현재 구조물 감시 시스템은 감지 능력, 데이터 처리, 피해의 양, 구조물의 상태 예상을 기본 목적으로 하여 운영된다. 기존 감시 시스템은 센서의 측정으로 얻은 데이터를 유선을 통해 기지노드로 전송한다. 유선으로 연결된 감시 시스템에는 많은 초기 설치비용, 네트워크 전송 케이블의 유실 문제와 같은 문제점이 있다. 본 논문에서는 이러한 문제점을 개선하기 위해 전송 장치, 센싱 보드, 무선 장치로 구성된 무선 네트워크 환경에서 동작하는 무선 감시 시스템을 구성하였다. 구현된 시스템은 하중에 따른 변화를 실시간으로 감시하므로 구조물의 안전성 향상에 기여한다.

• The Korean Journal of Rehabilitation Nursing
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• v.2 no.1
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• pp.45-60
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• 1999

This study was conducted to investigate the nursing diagnosis applying to rehabilitation unit. The subject of this study was consisted of 101 nurses who have been working over 1 year in rehabilitation unit. The clssification of nursing diagnosis used NANDA's system and analysis of the validity was based on Fehring's model. In summury of this study. some dirrerences were found in related factors in nursing diagnosis between rehabilitation and general unit. Major related factors of nursing diagnosis were physical factors associated with neuromuscular disorder. Valid related factors in altered nutrition more than body requirements was not found for rehabilitation unit. It is helpful for the nurses who work at rehabilitation unit to apply the nursing diagnosis validated in this study. This finding can be used as the database for accomplished nursing diagnosis appropriate for improving the rehabilitation nursing practice.

• Journal of the Korean Geographical Society
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• v.38 no.4
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• pp.591-609
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• 2003

The purpose of this study is to exhibit the characteristics and changes of city network in China through the analyses railway structures and movement of passengers and goods in China. On the basis of accessibility analysis., central China area shows the highest level of accessibility, and it declines toward periphery areas. The center of City network was transfered from the central area to the east. Three main lines from north to south and the central status of main cities remain unchanged. The city network stratum structure of China can be divided into three levels. The first level is in a pattern of linear distribution within provices along main lines. The second level, shows a pattern of strengthened linear distribution and crossed influencial regions. The third level includes 5 areas.

• Communications of Mathematical Education
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• v.29 no.2
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• pp.197-214
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• 2015

This study is to design Flipped Learning classrooms of learner-centered education on the pre-service math teachers education. The study aims to explore the feasibility of teaching and learning method. To achieve the objectives of the study was to explore the teaching and learning model. Flipped learing classroom design includes a main step of a typical process of teaching system. And we designed the model based on the ADDIE Model. This model contains the design steps and the Flipped learning component of the teaching and learning design model. Designed classroom presented in three steps that are before classroom, during classroom and after classroom.