• 화약ㆍ발파
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• 제30권1호
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• pp.1-8
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• 2012

본 연구에서는 충격 하중을 받은 콘크리트 재료의 내부 주응력 변화를 확인하기 위하여 Visual FEA 유한요소 프로그램으로 콘크리트 재료의 단면을 모델링하여 절점에서의 최대주응력을 분석하였다. 결과적으로, 콘크리트 재료의 탄성계수가 작을수록 최대주응력은 증가하는 것으로 나타났고, 콘크리트 재료의 물성 변화에 따라 최대주응력 편차는 2~3배 차이를 나타냈다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.351.1-351
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• 2002

In this research, the relationship between physical measurements and subjective evaluations of floor impact noise in apartment building was quantified by applying the neural network analysis due to its complex and nonlinear characteristics. The neural network analysis was undertaken by setting up L-value, inverse A index, Zwicker parameters and ACF/IACF factors, as input data, which came from the measurements at real suites of apartment building having various sound insulations. (omitted)

• Journal of Biosystems Engineering
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• 제22권1호
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• pp.49-58
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• 1997

Finding of internal quality is crucial for getting under control quality of watermelon after harvest. A maturity sensing device of watermelon using repulsion characteristics was developed and evaluated. In this study, five different sensing probes were used to detect the physical changes after impact on watermelons. Total 15 watermelons were tested and evaluated into two classes: ripe and unripe. It was difficult to detect the overripe watermelons using the proposed sensor. Therefore, the results showed that the developed sensor could be used to separate unripe watermelons after harvest. The results from this study are summarized as follows. 1. It was successful to distinguish between the ripe and unripe watermelon by sensing the elastic characteristics on impact. 2. The hemisphere was best for the shape of sensing part because the hemisphere concentrate stress in impact part. 3. Among the five type developed sensor, the 1, 2, 3. 5-type sensor showed good character in distinguishing between ripe and unripe watermelon.

• 한국안전학회지
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• 제34권5호
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• pp.95-102
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• 2019

Non-destructive methods such as rebound hardness method and ultrasonic method are widely studied for evaluating the physical properties, condition and damage of concrete, but are not suitable for detecting delamination and cracks near the surface due to various constraints of the site as well as the accuracy. Therefore, in this study, the impact resonance method was applied to detect the separation cracks occurring near the surface of the concrete slab and bridge deck. As a next step, the principal component analysis were performed by extracting various features using the FFT data. As a result of principal component analysis, it was analyzed that the reliability was high in distinguishing defects in concrete. This feature extraction and application of principal component analysis can be used as basic data for future use of machine learning technique for the better accuracy.

• 한국인구학
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• 제11권2호
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• pp.3-10
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• 1988

This study is a replication of Clemente and Sturgis' study conducted among 600 American cities in 1972. The impact of population size, physical density, social density, and age of 56 Korean cities upon the extent of their industrial diversification was analyzed. Hypotheses concerning each independent variable were generated from the theory of the development of the division of labor proposed by Durkheim and subsequently adopted by human ecologists. Zero-order correlation analysis and regression analysis were employed to test the hypotheses. The standardized partial regression coefficients indicated that social density and age of cities exert significant positive impact upon industrial diversification. On the other hand, population size showed a significant negative impact upon industrial diversification. In addition, it was discovered that the combined influence of the independent variables account for 34.6 percent of the variation in industrial diversification. The findings of this study were compared with the results of Clemente and Sturgis' study. Some suggestions for future research are presented and discussed.

• Advances in concrete construction
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• 제15권4호
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• pp.287-301
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• 2023

Hockey games attracts many fans around the world. This game requires a specific type of ball and a stick for controlling the motion and trace of the ball. This control of motion involves hitting the ball which is a direct intensive dynamic loading. The impact load transferred directly to the hand of the player and in the professional player may cause long term medical problems. Therefore, dynamic motion of the stick should be understood. In the current study, we analyze the dynamic motion of a hockey stick under impact loading from a hockey ball. In doing so, the stick geometry is simplified as a beam structure and quasi-2D relations of displacement is applied along with classical linear elasticity theory for isotropic materials. The governing equations and natural boundary condition are extracted using Hamilton's principle. The final equations in terms of displacement components are solved using Galerkin's numerical method. The results are presented using indentation and contact force values for variations of different parameters.

• 웰빙융합연구
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• 제7권3호
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• pp.43-53
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• 2024

Purpose: his study aims to explore how healthcare provider service characteristics in telemedicine services, which have become more common since the pandemic, affect rapport formation and service satisfaction with healthcare providers. Research design, data and methodology: A group of actual telemedicine users underwent data collection and empirical analysis. After analyzing reliability and validity, hypotheses were tested using a structural equation model. Results: Key perceived attributes of healthcare providers in telemedicine services were identified as doctor effort, doctor listening, and doctor expertise. Each of these variables had a significant positive impact on trust in telemedicine. Moreover, these attributes significantly positively impacted rapport formation and user service satisfaction, which was mediated by trust. However, the direct impact of rapport formation on service satisfaction was not supported. Conclusions: The study's findings have academic and practical implications for expanding telemedicine services. As an initial empirical study on telemedicine services, it confirms the importance of trust and rapport formation even in non-face-to-face medical situations. In order to overcome the limitations of non-physical contact, telemedicine services should strive to develop UI/UX designs that are more interoperable and boost trust in service apps.

• 한국산학기술학회논문지
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• 제11권9호
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• pp.3380-3389
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• 2010

본 연구의 목적은 대학생들의 교양체육 수업만족도가 운동지속의사에 미치는 영향을 규명하여 대학교 교양체육 수업을 더욱 활성화시키고 확대할 수 있는 방안을 모색하여 학생들이 지속적으로 체육활동에 참여할 수 있는 기초 자료를 제시하고자 하였다. 따라서 본 연구에서는 2009년 현재 대전시 및 충남에 소재한 4년제 대학에 재학 중인 남 여를 대상으로 486명을 표집하여 설문지를 실시하였다. 수집된 자료는SPSS 14.0을 사용하여 빈도분석, 신뢰도 분석, 기술통계분석, t-test와 일원변량분석(one-way ANOVA) 및 상관분석을 실시하였고, 다음과 같은 결론을 얻었다. 대상자의 일반적 특성에 따른 수업만족의 하위요인 및 운동지속의사 차이에서 성별, 전공별, 학년에서 부분적으로 유의한 차이가 나타났으며, 상관관계에서 수업만족도의 하위요인과 운동지속의사 간의 모두 정적(+) 상관을 나타내었다. 또한 교양체육의 수업만족도는 운동지속의사에 높은 영향을 미치는 것으로 나타났다. 이는 수업만족도가 높을수록 운동지속의사가 높음을 의미하며, 차후 평생체육에 참여를 유도하기 위해 대학 교양체육의 역할을 제시하고 있다.

• The Journal of Korean Physical Therapy
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• 제35권3호
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• pp.57-63
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• 2023

Purpose: The aim of this study was to conduct a systematic review of randomized controlled studies from 2012 to present that explore the diagnostic accuracy of clinical tests used for diagnosing anterior cruciate ligament (ACL) injury. Methods: Study design: Systematic review. Literature search of the PubMed and Scholar databases was conducted using keywords related to diagnostic accuracy of clinical tests for ACL injury. The PRISMA Guidelines were followed to conduct this study. The Cochrane Risk of Bias Tool was utilized to assess the quality of each included study. Results: As a result, 8 studies were included, and 6 clinical tests used in ACL tears were evaluated for diagnostic accuracy. The pivot shift test was reported as having the highest +LR (29.5) value with a sensitivity of 59% and a specificity of 98%. However, the test with the lowest -LR value was the lever test, and the values were as follows: -LR (0.08), +LR (4.7), specificity (80%), sensitivity (94%). Conclusion: In this study, it was concluded that a single clinical test is not sufficient to determine the presence of ACL injury. Test combinations have a higher diagnostic accuracy than a single test. In this study, the accuracy of the clinical tests was examined without considering the amount of ACL rupture and acute-chronic condition. Further research is required to examine the impact of these two factors on diagnostic accuracy of clinical test.

• 환경정책연구
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• 제8권2호
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• pp.63-82
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• 2009

도로, 철도, 공항을 포함하는 교통시설에 의한 교통소음으로 인하여 많은 사람들이 신체적 및 정신적인 피해를 받고 있는 가운데 선진국의 경우 교통소음에 노출된 인체 건강의 위험성을 인지하고 그것을 해결하기 위한 많은 연구가 수행되고 있다. 이러한 연구흐름에 따라 본 연구에서는 교통소음의 건강영향에 대한 국내외 연구결과를 바탕으로 하여 국내 교통소음에 의한 건강위해성을 평가할 수 있는 기본적인 방안을 모색해 보고자 한다. 교통소음의 건강영향에 대한 평가방법 중에서 많은 연구가 진행되고 있는 교통소음에 의한 성가심 및 수면방해 연구는 교통소음의 측정자료 및 설문조사결과를 바탕으로 소음지표에 대한 불쾌감 및 수면방해 호소비율의 관계를 보여주고 있다. 이에 대한 국내외의 노출-반응 예측결과를 비교해 보면 우리나라 사람들이 다른 나라 사람들보다 교통소음에 대해 대체로 더 높은 소음성 불쾌감 및 수면방해를 호소하는 것을 알 수 있다. 교통소음의 건강영향에 대한 연구결과 및 외국의 사례를 바탕으로 교통소음의 건강위해성을 평가할 수 있는 기본적인 방안을 제시하였는데 그에 대한 내용은 국내 교통소음 건강영향 예측모델의 개선을 통한 객관적인 평가기준 마련과 아울러 교통소음에 대한 사람들의 인식정도나 소음환경의 질을 향상시킬 수 있는 저감방안 마련을 포함한다.