• Journal of Advanced Navigation Technology
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• v.16 no.4
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• pp.571-577
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• 2012

In this paper, we design a flight controller using a dynamic compensator for a small unmanned aerial vehicle. The proposed method ensures flight stability during altitude holding and waypoints passing by improving the transient response and steady state error. The control system consists of dual feedback loops with an inner loop and a outer loop. The inner loop has a PD controller to improves the transient response and the outer loop has a dynamic compensator to reduce overshoot in the transient response and improve the steady state error. The performance of the proposed method is evaluated by flight test on a small UAV.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.3
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• pp.1-6
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• 1990

The dynamic behaviour of a four-span continuous girder railway bridge subjected to multiple support excitations is investigated using the response spectrum method. Small-amplitude oscillations and linear-elastic material behaviour are assumed. Soil-structure interaction effects are disregarded and only the out-of-plane response of the bridge is considered. The results of the response spectrum analysis are compared with those from a time history analysis. Different combination rules for the superposition of modal maxima as well as supports are employed, such as square-root-of-sum-squares, double sum and p-norm methods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.437-444
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• 2016

This study was carried out to investigate food label perception and utilization classified by age and sex. Questionnaires were collected from 938 male and female customers aged in their 20's to 50's from February 4th to March 30th 2014. Regarding checking food labels at the time of purchase, 73.8% of consumers checked food labels, and there was a significant difference by age and sex. Female more often checked food labels than males, and the 40's group showed a higher ratio of checking food labels than other age groups. The main reason for checking food label was 'confirming expiration date' (60%), 'ingredients' (16.4%), and 'nutrition contents' (13.7%). The main reason not checking food labels was 'too small and insufficient to understand' (50.3%), 'too difficult to understand' (16.4%), and 'have no concern' (14.9%). There was a significant difference by age, as in the 50's group showed a higher ratio of 'too small and insufficient to understand' than the other age groups, and 20's and 30's groups showed a higher ratio of 'too difficult to understand'. The overall satisfaction score was 2.96, awareness score was 2.88, and reliability score was 2.93. A total of 96% answered that food labelling education is needed. Therefore, food labelling education for consumers is required to encourage consumers to purchase healthy foods.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.6
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• pp.523-530
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• 2017

In this study, a method of probabilistic evaluation of the performance point of the structure obtained by capacity spectrum method (CSM) is presented. The performance point of the 4-story and 1-bay steel structure was determined by using CSM according to ATC-40. In order to analyze whether the demand spectrums exceed the performance limit of the structure, the limit displacements are derived for the performance limit of the structure defined from the plastic deformation angle of the structural member. In addition, by selecting a total of 30 artificial seismic wave having the response spectrum similar to the design response spectrum, the fragility curves were derived by examining whether the response spectrum obtained from the artificial seismic wave were exceeded each performance limit according to the spectral acceleration. The maximum likelihood method was used to derive the fragility curve using observed excess probabilities. It has been confirmed that there exists a probability that the response acceleration value of the design response spectrum corresponding to each performance limit exceeds the performance limit. This method has a merit that the stochastic evaluation can be performed considering the uncertainty of the seismic waves with respect to the performance point of the structure, and the analysis time can be shortened because the incremental dynamic analysis (IDA) is not necessary.

• 한국노년학
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• v.25 no.2
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• pp.143-154
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• 2005

This study was conducted to examine the environmental status, FIM(Function Independence Measure), Illness intrusiveness of home stayed stroke patients. Data were collected on 145 patients living in K city and the neighborhood located in southern part of Korea. The data were analyzed by means of SPSS program. Results : In assessment of environmental safety, 46.2%(67) felt unsafe around their residential area. The most dangerous facilities in their residence was stairs(58.2%), gas/electric facilities(14.9%). For sanitary problems, 28.2%(41) felt they have problems at their home. The most important problems were outdoor polluted toilet(22.0%) and scattered and dirty residential circumstances(22.0%). The average FIM score was 74.52(4.14) of total score 126(7). In motor area FIM was lowest at stair walking(3.01) and bathing(3.16). In cognitive area FIM was lowest at social activities(3.36). The mean score of Illness intrusiveness was 58.86(4.52) of total score 91(7). The major area largely impacted by stroke were health(5.61), working(5.68), active leisure activities(5.56). There was significant reverse correlation between FIM and illness intrusiveness(r=-0.66, p=0.00). Conclusion : It was needed environmental improvement and rehabilitation program for stroke patients, and repeated follow up study.

• Journal of Nutrition and Health
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• v.42 no.6
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• pp.536-546
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• 2009

This study was done to investigate the effect of stress on appetite and eating habits, and other health-related behaviors. The subjects of this study consisted of 188 males and 224 females in Ulsan area. The results were as follows: When stressed, 56% (n = 231) of the subjects experienced a change in appetite and of these, 32% (n = 132) experienced an increased appetite. Stress-induced eating may be one factor contributing to the development of obesity. There was a gender-specific response to stress in which women are more likely to use food to deal with stress, whereas men are more likely to use alcohol consumption or smoking. It was found that types of stressors were individual (52.9%), social (50.7%), family relations (34.5%), work demands (34.2%) and physical environment (32.3%). Stress-induced symptoms of the subjects were anxiety (38.3%), headache (36.7%) and neck or shoulder aches (36.2%), and females experienced those symptoms more than males. Those older than 50 years had a higher eating habit score and lower stress score compared with younger subjects. There were significant differences between sex, age, occupation, family type, BMI, exercise, sleeping hours and eating habits or stress level. This study may be helpful in advancing findings in this area to better provide health professionals with appropriate counseling tools to improve the health of all individuals.

• Journal of KSNVE
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• v.7 no.6
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• pp.899-908
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• 1997

본 글에서는 소형 압축기 셸과 같은 비교적 복잡한 기계 구조물의 간접적 입력 측정에 대한 결과 및 직접 측정과의 비교를 기술하였고 다수 응답의 동시 측정에 따른 문제점을 해결코자 기준점을 이용한 전달함수의 측정 방법을 제시 하였다. 하부 빈 셸에 대한 실험 결과, 압축기의 셸과 같은 비교적 복잡한 구조물에 대해서도 간접 입력 측정을 상당한 신뢰성을 갖고 시도할 수 있으며 특히 공진점이나 영점 부근에서의 추정 오차는 측정점의 갯수를 증대시킴으로써 크게 개선 시킬수 있음을 보여주었다.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.25-27
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• 1998

나프탈렌으로부터 제조된 메조페이스 핏치(NMP)와 개질된 등방성 콜타르 핏치(MCP)의 방사성을 유변학적거동에 기초해 설명하고자 시도되었다. 기본적으로, 방사성은 l/4, l/l, 4/1(wt. NMP/wt. MCP)로 블렌드비를 달리 하면서 shear rate를 증가시켰을 때 등방성의 농도가 클 경우 급격한 점도 감소로 cohesive fracture의 원인이 됨을 관찰할 수 있었고 NMP가 증가할수록 탄성에너지 값이 전형적인 고분자의 거동처럼 응답하는 tan $\delta$값의 임계점이 고주파수영역으로 이전되어 최대값을 나타내었고 임계점보다 낮은영역에서 상대적인 크기는 NMP가 증가함에 따라 작아지는 현상을 관찰할 수 있었다.(중략)

• Product Safety
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• no.2 s.158
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• pp.68-68
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• 2007

우리나라의 전기용품안전관리법은 1974년 1월 4일자로 공포되어 30년이 넘게 운영되어 오고 있습니다. 그동안 크고 작은 개정이 여러번 있었고 2000년 7월 1일자로 형식승인이 안전인증으로 바뀌는 등 대폭 개정되어 지금에 이르고 있습니다. 이와 관련하여 업체에서 궁금한 점을 질의한 것을 기술표준원 제품안전정책과에서 응답한 내용중 꼭 숙지하여야 한다고 판단되는 질의와 응답을 여기에 게재하오니 전기용품제조∙수입업체의 많은 참조가 있기를 바랍니다.

• Product Safety
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• no.4 s.160
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• pp.62-62
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• 2007

우리나라의 전기용품안전관리법은 1974년 1월 4일자로 공포되어 30년이 넘게 운영되어 오고 있습니다. 그동안 크고 작은 개정이 여러번 있었고 2000년 7월 1일자로 형식승인이 안전인증으로 바뀌는 등 대폭 개정되어 지금에 이르고 있습니다. 이와 관련하여 업체에서 궁금한 점을 질의한 것을 기술표준원 제품안전정책과에서 응답한 내용중 꼭 숙지하여야 한다고 판단되는 질의와 응답을 여기에 게재하오니 전기용품제조∙수입업체의 많은 참조가 있기를 바랍니다.