• 한국가정과학회지
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• 제7권1호
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• pp.113-129
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• 2004

This study was pursued to examine the differences in housewives' willingness of buying genetically modified(GM) Food by the basic knowledge and recognition toward GMO. The results could provide a basic information for the consumer education and consumer policy about genetically modified food. The final 723 observations collected using a questionnaire were analysed by frequency, percentage. mean, standard deviation, t-test.$X^2$. ANOVA. and duncan-test using the SPSS/WIN 10.0 programs. The main results were following (1) Consumers' basic knowledge about GMO was too low to understand or interpretate information regarding GM food which was provided or would be provided. So consumers education for very basic biology should be offered for consumer to understand and interpretate various information about GM food is provided. (2) Consumers didn't trust GM food information provided by government. however they wanted government to provide information regarding GM food. (3) The more basic biology knowledge consumer has, the better recognition of GM food and the higher possibility that they eat consumer has.

• 한국항공우주학회지
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• 제42권8호
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• pp.674-682
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• 2014

RFTS(Radio Frequency Test Set)은 저궤도 위성과 정지궤도 위성의 AI&T 기간 동안 TC&R RF 서브시스템을 검증하는 필수 장비이다. 본 논문에서는 새로운 RFTS의 상세 설계 내용을 제시하는데 기존의 RFTS와 달리 위성 프로젝트 별 시험 수행 시 수정 없이 바로 적용할 수 있도록 하였다. 하드웨어와 소프트웨어는 이를 만족하도록 설계 되었고 기능 별 모듈화와 상용품 사용의 확장으로 보다 손쉬운 제어와 운용이 될 수 있도록 하였으며 시스템의 신뢰성 향상을 가져오도록 하였다. 또한 보다 정확한 기준 클락을 채택하여 RF 측정에 대한 신뢰도를 높였다.

• Steel and Composite Structures
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• 제46권3호
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• pp.353-366
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• 2023

This paper presents a finite-element analysis (FEA) of aluminum alloy rectangular hollow sections (RHSs) and square hollow sections (SHSs) with circular through-openings under three-point and four-point bending. First, a finite-element model (FEM) was developed and validated against the corresponding test results available in the literature. Next, using the validated FE models, a parametric study comprising 180 FE models was conducted. The cross-section width-to-thickness ratio (b/t) ranged from 2 to 5, the hole size ratio (d/h) ranged from 0.2 to 0.8 and the quantity of holes (n) ranged from 2 to 6, respectively. Third, results obtained from laboratory test and FEA were compared with current design strengths calculated in accordance with the North American Specifications (NAS), the modified direct strength method (DSM) and the modified Continuous strength method (CSM). The comparison shows that the modified CSM are conservative by 15% on average for aluminum alloy RHSs and SHSs with circular through-openings subject to bending. Finally, a new design equation is proposed based on the modified CSM after being validated with results obtained from laboratory test and FEA. The proposed design equation can provide accurate predictions of flexural capacities for aluminum alloy RHSs and SHSs with circular through-openings.

• 공학교육연구
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• 제16권4호
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• pp.15-20
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• 2013

The result of the English test for freshmen showed wide difference in the ability of students, which means the graded class is strongly required. This paper describes the case study about the graded English class that was carried out for the freshman. Every freshman must take an English placement test from problems bank and were classified according to the result of the test. In order to resolve the dissatisfaction of the high level students, the statutes of my university for credit were modified. In order to analyze the effect of the graded class, evaluation test using similar problems was carried out at the end of the semester. The effect of the graded class was analyzed by using the paired samples t-test method and there was a meaningful performance improvement at the average score. Additional improvements in the method of classification and credit granted were made by analyzing the results of the evaluation test and survey.

• 한국전문물리치료학회지
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• 제6권3호
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• pp.51-58
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• 1999

In general, sitting balance is decreased in subjects with spinal cord injury. The purpose of this study was to evaluate the inter- and intra-rater reliability of the Functional Reach Test (FRT) which is used to measure sitting balance. The subjects of this study were 26 persons with spinal cord injury, and they were divided into three groups according to their injury level. Group I, II and III consisted of the following $C_5{\sim}C_8$ quadriplegics, $T_1{\sim}T_4$, and $T_9{\sim}T_12$ paraplegics, respectively. Subjects sat on a mat table that was set at an 80 degree inclination. During three sessions, the length subjects could reach in the FRT test was measured by three physical therapists, and compared to each other. The results showed that intraclass correlation coefficients (2,1) were above 0.97 and inter-rater difference was not statistically significant. The one-way ANOVA demonstrated that reach differed between groups with lower thoracic lesion and the other test groups. In conclusion, we think modified FRT is useful and reliable method to measure the sitting balance in subjects with spinal cord injury.

• 한국운동역학회지
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• 제29권3호
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• pp.197-204
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• 2019

Objective: The purpose of this study was to identify the effect of high-heels (HH) modification on metatarsal stress in female workers. Method: Seven females who work in clothing stores ($heights=160.4{\pm}3.9cm$; $weights=47.4{\pm}4.1kg$; $age=31.3{\pm}11.1yrs$; $HH\;wear\;career=8{\pm}6.5yrs$) wore two types of HH (original and modified). The modified HH had been grooved with 1.5 cm radius and 0.2 cm depth around the first metatarsal area inside of the shoes using the modified shoe-last. Participants were asked to walk for 15 minutes on a treadmill and to stand for 10 minutes with original and modified HH, respectively. Kinetics data were collected by the F-scan in-shoe system. After each test, participants were asked to rate their perceived exertion using the Borg's 15-grade RPE scale and interviewed about their feeling of HH. Nonparametric Wilcoxon signed-rank test and effect size (Cohen's d) were used to determine the difference of the variables of interest between the original and modified HH. Results: In the present study, modified HH of the peak contact pressure of 1st metatarsal (PCP) left, PCP right, pressure time integral (PTI) left, peak pressure gradient (PPG) left during standing and PPG right during walking are greater than original HH. And even it didn't show statistically significant, the average in all pressure values of modified HH showed bigger than original HH. It surmised to be related to awkward with modified HH. Even though they said to feel the comfortable cause of big space inside of HH in the interview, they seemed to be not enough time to adapt with new HH. So their walking and standing postures were unstable. Conclusion: Modified the fore-medial part of HH can reduce the stress in the first metatarsal head and big toe area during standing and walking.

• 대한통합의학회지
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• 제7권2호
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• pp.189-195
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• 2019

Purpose : The purpose of this study was to investigate the effects of chin tuck exercise (CTE) on the craniovertebral angle (CVA), strength and endurance of deep cervical flexor (DCF) muscles in subjects with forward head posture(FHP). This study was performed on 30 subjects with FHP. Method : Thirty subjects were divided into two groups; modified CTE (n=15), conventional CTE (n=15). Both of the group performed the exercise 4 times a week for 6 weeks. The subjects performed CTE in two different methods; modified CTE, with device designed that help keep cervical lordois curve, and coventional CTE, without using device. The CVA was measured using Image software version. A pressure biofeedback unit was used to measure the strength and endurance of the DCF muscles. The data was analyzed by the paired t-test for comparing before and after changes of variables in each group and the independent t-test for comparing the between groups. Result : There was statistically significant difference of before and after strength and endurance of DCF muscles in modified CTE (p<0.05). There was statistically significant difference of before and after only endurance of DCF muscles in conventional CTE (p<0.05). There was statistically significant difference of between the two group in strength of DCF muscles (p<0.05). Conclusion : Muscle strength to stabilize the spine plays an important role in maintaining a good posture. Therefore, we suggest that the application of CTE with a device designed to maintain the lordotic curvature in the neck is likely to yield better outcomes in FHP subjects in future studies.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2002년도 춘계학술대회논문집
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• pp.197-203
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• 2002

The estimation of pile bearing capacity is important since the design details are determined from the result. There are numerous ways of determining the pile design load, but only few of them are chosen in the actual design. According to the recent investigation in Korea, the formulas proposed by Meyerhof based on the SPT N values are most frequently chosen in the design stage. In the study, various static and dynamic formulas have been used in predicting the allowable bearing capacity of a pile. Further, the reliability of these formulas has been verified by comparing the perdicted values with the static and dynamic load test measurements. Also in cases, these methods of pile bearing capacity determination do not take the time effect consideration, the actual allowable load as determined from pile load test indicates severe deviation from the design value. The principle results of this study are summarized as follows : A a result of estimate the reliability in criterion of the Davisson method, in was showed that Terzaghi & Peck > Chin > Meyerhof > Modified Meyerhof method was the most reliable method for the prediction of bearing capacity. Comparisons of the various pile-driving formulas showed that Modified Engineering News was the most reliable method. However, a significant error happened between dynamic bearing capacity equation was judged that uncertainty of hammer efficiency, characteristics of variable , time effect etc... was not considered. As a result of considering time effect increased skin friction capacity higher than end bearing capacity. It was found out that it would be possible to increase the skin friction capacity 1.99 times higher than a driving. As a result of considering 7 day's time effect, it was obtained that Engineering News. Modified Engineering News. Hiley, Danish, Gates, CAPWAP(CAse Pile Wave Analysis Program ) analysis for relation, respectively, $Q_{u(Restrike)}$ $Q_{u(EOID)}$ = 0.971 $t_{0.1}$, 0.968 $t_{0.1}$, 1.192 $t_{0.1}$, 0.88 $t_{0.1}$, 0.889 $t_{0.1}$, 0.966 $t_{0.1}$, 0.889 $t_{0.1}$, 0.966 $t_{0.1}$

• 한국콘텐츠학회논문지
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• 제11권4호
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• pp.273-282
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• 2011

본 연구는 국소 허혈성 뇌손상 흰쥐 모델에서 tDCS의 자극 적용시간을 달리하였을 때, 앞다리 운동감각 기능변화와 신경영양인자(GAP-43)발현에 미치는 영향을 알아보고자 하였다. 뇌손상 모델은 Sprague -Dawley계 흰쥐 80마리를 'Longa'방법을 이용하여 중대뇌동맥(middle cerebral artery)을 폐색하여 유발하였고, 실험군을 4개로 나누었다; 실험군I은 허혈성 뇌손상 유발군(n=20), 실험군II는 허혈성 뇌손상 유발 후 tDCS(10분) 적용군(n=20), 실험군III은 허혈성 뇌손상 유발 후 tDCS(20분) 적용군(n=20), 실험군IV는 허혈성 뇌손상 유발 후 tDCS(30분) 적용군(n=20)으로 나누었다. 앞다리운동감각 기능검사를 위해 수정된 앞다리배치 검사와 단일 팰릿 닿기 검사를 실시하였으며, 신경가소성에 대한 면역조직화학적 검사로 운동감각 영역에서의 GAP-43 단백질 발현을 관찰하였다. 앞다리운동감각 검사는 14일에서 실험군III (p<0.05)이 다른 군들에 비해 유의한 차이를 보였으며, 단일 팰릿 닿기 검사는 14일에서 실험군III(p<0.01)과 실험군IV(p<0.05)에서 유의한 차이를 보였다. 또한, 면역조직학적 검사는 14일에 실험군III이 다른 군들에 비해 현저한 면역양성반응의 증가를 보였다. 따라서, 0.1 mA의 강도로 20분간 적용했을 때가 앞다리운동감각 기능과 신경가역성 인자 GAP-43 발현에 가장 좋은 조건임을 알 수 있었다.

• Advances in concrete construction
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• 제7권2호
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• pp.97-105
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• 2019

In this paper, the workability and static stability were evaluated using a proposed test method. Workability and static stability represent a key property of self-compacting concrete (SCC) in fresh state. A number of standardized test methods were developed to assess these properties. However, no accelerated test method reliably predicts both workability and static stability of SCC. In the present work, a modified K-slump test method was developed to evaluate workability and static stability of SCC. In order to take implicit mixture variations of SCC constituents that can affect fresh SCC properties, a central composite design was adopted to highlight the effect of gravel to sand ratio (G/S), gravel 3/8 to gravel 8/15 ratio (G1/G2), water to cement ratio (W/C), marble powder to cement ratio (MP/C) and superplasticizer content (SP) on workability measured with slump and flow time (T50) tests and static stability measured with sieve stability test (Pi), segregation test index (SSI), Penetration test (Pd) and the proposed K-slump test (Km). The obtained results show that G/S ratio close to 1 and G1/G2 ratio close to 60% can be considered as optimal values to achieve a good workability while ensuring a sufficient static stability of SCC. Acceptable relationships were obtained between Slump flow, Pi, Pd and Km. Results show that the proposed K-slump test allow to assess both workability and static stability of fresh SCC mixtures.