• 한국운동역학회지
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• 제32권4호
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• pp.134-140
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• 2022

Objective: This study aims to verify effect of 1-RM direct measurement method of back squat on beginners. Method: Total of 8 healthy adults were recruited for this study (age: 29 ± 3.81 yrs., height: 174 ± 3.83 cm., body mass: 74 ± 11.63 kg., 1RM: 96 ± 19.78 kg). All participants performed the back squat with 80%, 90% and 100% of the pre-measured 1RM. A three-dimensional motion analysis was performed with 8 infrared cameras and 3 channels of EMG were used for this study. One-way ANOVA with repeated measure was used for the statistical analysis with the significant level set to α=.05. Results: The ankle joint ROM in the transverse plane was significantly increased as the weight increased during the concentric contraction phase 2 (p < .05). In addition, the erector spinae and the gluteus maximus, which are synergist for the motion, showed a significant difference according to the increased weight (p < .05). Conclusion: Our results revealed that beginners increase potential dynamic knee valgus as weight increased. Therefore, it is thought that field coaches should pay attention to this to minimize and prevent injuries when measuring 1-RM for beginners.

• The Journal of Korean Physical Therapy
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• 제34권4호
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• pp.168-174
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• 2022

Purpose: The purpose of this study was to analyze the correlation between balance control ability and leg circumference, proprioception, range of motion (ROM), and muscle strength in young adults. Methods: The subjects of this study were 30 university students who were enrolled in D university in Gyeongbuk province. We measured the dynamic balance and static balance using the Biorescue. The muscular strengths of the hip, knee, and ankle joints were measured using a muscle contraction dynamometer. The ROM and proprioception were measured using an inclinometer. Pearson correlation analysis was used to test the correlations between balance control ability and variables. Results: Sway length was significantly correlated with knee and hip joint muscle strength, ROM, and proprioception of hip and ankle joints (p<0.05). Sway speed was significantly correlated with ROM and proprioception in hip joints (p<0.05). Limit of stability was significantly correlated with muscle strength and ROM in ankle joints, and proprioception in hip, knee, and ankle joints (p<0.05). Conclusion: The sway length was most related to hip extension and ankle joint plantar flexion in the range of motion and ankle joint plantar flexion in proprioception. Overall, balance training for young adults will be of effective help if the treatment focuses on the knee and hip joints, range of motion and the ankle and hip joints' proprioception.

• The Journal of Asian Finance, Economics and Business
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• 제9권3호
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• pp.33-42
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• 2022

Oil prices have become more volatile as a result of global economic contraction and control measures. Before and during the COVID-19 crisis, this study examines the relationship between oil price swings and daily stock returns in the power sector. The impact is investigated using a panel Vector Autoregressive (VAR) model. Granger causality tests are used to see if oil prices are effective in predicting returns. The dynamic impact of supply shocks is studied using Impulse Response Functions (IRFs). From January 2011 to May 2021, the study used daily data from all listed power sector enterprises on the Pakistan stock exchange. To investigate the differences in reactions between the Pre-COVID and COVID eras, the sample was separated into two groups. Oil shocks are inversely associated with daily firm stock returns. The conclusions are further supported by the lack of impact of stock prices on oil prices. The relationship, however, deteriorates during the COVID pandemic. We could not uncover any evidence of a significant relationship. In developing countries that rely on oil imports, the study sheds light on the utility of oil price shocks in daily stock return predictions.

• 한국해안·해양공학회논문집
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• 제23권1호
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• pp.34-42
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• 2011

지구온난화로 인한 태풍 강도 증가와 장기해수면 상승에 대처하기 위하여 호안 및 방파제의 마루높이를 고정식으로 증가시키는 것이 일반적이다. 그러나 이와 같은 대처방식은 월파저지에는 효과적이나 수변공간의 바다 조망권을 저하시키는 단점을 가지고 있다. 본 연구에서는 황천 시에 전개시키고 평상 시 격납하여 월파저지와 조망권 확보 기능을 동시에 달성할 수 있는 일종의 동적 가변형 구조물인 고무막체 파라펫의 개발을 시도하였다. 본 구조물은 순전히 공기의 주입 및 배출에 의하여 제어되는 무인 작동 구조물로서 해황에 따라 원격제어가 가능하다. 고무막체 파라펫의 여러 최적형상이 도출되었으며 비선형 유한요소 프로그램을 사용한 수치해석 및 수리모형실험을 통하여 이들 파라펫들의 전개 및 격납 과정, 그리고 월파발생시의 거동 및 구조적 안정성을 검토하였다.

• 콘크리트학회논문집
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• 제17권3호
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• pp.385-392
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• 2005

본 연구는 재생골재 콘크리트의 적극적인 활용을 위하여 재생굵은골재를 대체율에 따라 혼합골재로 하는 재생골재 콘크리트의 동결응해 저항성, 탄산화 저항성 및 건조수축에 대한 시험을 실시하여 내구특성의 영향요인을 분석하고 내구성 증진방안을 강구함으로써 재생골재 콘크리트의 품질과 신뢰성을 확보하는데 그 목적이 있다. 연구결과는 다음과 같다. (1) 재생굵은골재를 혼합골재로 하는 재생골재 콘크리트의 동결융해 저항성은 모든 대체율에서 $90\%$를 상회하는 상대동탄성계수로 나타나 우수한 결과를 보였으며, 전 사이클에서는 $99.2{\~}91.0\%$의 상대동탄성계수의 범위를 보여 쇄석을 사용한 보통 콘크리트의 상대 동탄성계 수 범위인 $97.5{\~}90.6\%$에 비해 향상된 내동해성으로 나타났다. (2) 재생골재 콘크리트의 촉진탄산화 깊이는 대체율이 증가함에 따라 대체하지 않은 보통 콘크리트와 유사하거나 다소 감소하는 경향으로 나타났다. (3) 재생굵은골재를 혼합골재로 하는 재생골재 콘크리트의 건조수축에 의한 길이변화율은 전 배합에서 쇄석을 사용한 보통 콘크리트보다 $18.5{\~}3.9\%$ 작게 나타났다.

• 대한정형도수물리치료학회지
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• 제18권2호
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• pp.41-47
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• 2012

Background: This study was designed to investigate the correlation between electromyography (EMG) activities in the vastus medialis oblique (VMO) vs vastus lateralis (VL) activity ratio and the valgus collapse knee position while stepping down. Methods: Twenty healthy women volunteered to participate in this study. We measured the frontal-plane projections of the knee valgus angle, knee valgus distance, and hip adduction angle by using a digital camcorder. After 3 repetitions of the step down (dominant side) exercise, the findings of the static and dynamic phases were analyzed. EMG activities data of the VMO:VL activity ratio were recorded during the step down exercise and were normalized to the maximal voluntary isometric contraction (MVIC) of the quadriceps. A paired t-test was used to compare the findings of the static and dynamic phases. We analyzed the Spearman's rank order correlation coefficient between the and VMO:VL ratio. Results: Hip adduction angle, knee valgus angle, VMO activity, VL activity, VMO:VL activity ratio were statistically higher in the dynamic phase than in the static phase (p<.05). Frontal-plane projections of knee valgus angle were significantly correlated with hip adduction angle (r=.459, p<.05) and knee valgus distance (r=.505, p<.05). However, the EMG activity ratio of the VMO and the VL did not show a significant change during step down exercise with respect to hip adduction angle (p=.875), knee valgus angle (p=.618), and knee valgus distance (p=.701). Conclusion: The results from this study indicate that frontal-plane projections of knee valgus angle were associated with hip adduction angle and knee valgus distance. On the basis of these results, the knee valgus distance may be used to determine the valgus collapse knee position while stepping down.

• 한국실내디자인학회논문집
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• 제13권3호
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• pp.84-92
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• 2004

This study concentrates on a new idea that is formulated as a creative spatialization in contemporary architecture and painting. It is stimulated from the classical baroque, which is expressed with the conceptual instruments, 'excessive', 'decorative', 'accidential' Suggested from that, this study tries to open the actual sense area of 'the baroque' by analysing the architectural ideas of wrenching and folding by Frank O. Gehry and in the same context by elucidating the dynamic deformalising of the figures by Francis Bacon. The redefined 'new baroque' operates in the chain of the transformable and flexible images that must be recognized as 'the real' in the sense of 'the most empirical' and are vulnerable to dispersal. The typical instrument of Gehry's 'new baroque architecture' is the enclosing of the space and its folding, and Bacon, whose painting can be called as the modern baroque, takes as the expressing methods a wrenching of the figures, a relieving of the colored background against the figure and a disappearing of figures into the background. These different ideas meet in the theoretical gravitation field of the philosophy of Deleuze, in which the reconstituted baroque conception means the tension between the folds, on expansion and contraction of which the variable space is dependent, Through the general principle of 'the new baroque', a free dispersal of power, to architect and painter is offered the possibility, not only to make the real world intimate to the real life, but also to produce from there a vivid new space. Finally it brings to enjoyer and viewer the possibility, to perceive the operating power in and around oneself.

• 한국환경과학회지
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• 제25권6호
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• pp.853-864
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• 2016

Meteo-tsunamis are tsunamis that are typically caused by strong atmospheric instability (e.g., pressure jumps) in low pressure systems, but some meteo-tsunamis in winter can be caused by local atmospheric instability in high pressure systems (e.g., the Siberian High). In this study, we investigated a meteo-tsunami event related to a high pressure system that occurred during winter on the Yellow Sea in 2005. Sea level data from tidal stations were analyed with a high-pass filter, and we also performed synoptic weather analyses by using various synoptic weather data (e.g., surface weather charts) collected during the winter season(DJF) of 2005. A numerical weather model (WRF) was used to analyze the atmospheric instability on the day of the selected event (21 Dec. 2005). On the basis of the results, we suggest that the meteo-tsunami triggered by the high pressure system occurred because of dynamic atmospheric instability induced by the expansion and contraction of the Siberian High.

• 한국산업정보학회논문지
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• 제16권3호
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• pp.121-135
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• 2011

본 연구는 클라우드 컴퓨팅 서비스 투자 및 경제적 효과에 관련된 기술의 연구현황 및 사례들을 바탕으로 경제성 분석 모형을 제공한다. 플라우드 컴퓨팅 서비스가 기업에 가져올 수 있는 비용절감 만을 편익으로 계상함으로써 투자안들의 편익 및 비용을 보수적이며 효율적으로 파악할 수 있다. 기존 정보시스템을 대체할 논클라우드, 클라우드 방식의 투자안을 정태적인 NPV 분석방식 그리고 불확실성 및 전략적 옵션을 반영한 동태적인 실물옵션 분석 방식을 활용하여 비교하였다. 정태적인 NPV방식의 경제성 분석은 기업이 가진 전략적인 옵션의 가치를 제대로 평가하지 못하는 단점을 지적하고 있으며 실물옵션에 기반한 경제성 분석은 시장변수들과 기업이 전략적인 옵션이 클라우드 투자안들의 경제성에 미치는 영향을 함께 분석할 수 있다.

• 화약ㆍ발파
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• 제22권4호
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• pp.7-15
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• 2004

본 연구에서는 PFC3D를 사용한 폭원모델링 기법을 제안하고, 제안된 기법을 시멘트 모르타르와 같은 연약재료의 발파에 적용하여 그 적용성을 시험해 보았다. PFC3D는 개별요소법(DEM)을 기반으로 하고 있어 응력파의 전파와 재료의 동적 파괴현상을 모사하는데 적합한 코드로 분류된다. 폭원모델링 과정에서는 공내입자들의 반경을 팽창/수축시키는 기법을 통해 공벽입자들에 접촉력의 형태로 폭발압력을 부여하는 방법을 사용하였으며, 입력하중에 따라 공벽에서 유발되는 접촉력을 계산단계마다 측정 및 보정함으로써 폭발압력의 크기를 제어할 수 있도록 하였다. 시멘트 모르타르 블록의 발파모델링 과정에서는 기존의 외력을 이용하는 방법과 본 연구에서 제안하고 있는 접촉력을 이용하는 기법을 각기 적용함으로써 연약재료의 파괴과정을 정성적으로 비교하여 보았다. 해석결과, 제안된 폭원모델링 기법을 적용한다면 암석이나 콘크리트와 같은 공학재료들이 발파과정에서 보이는 파괴거동을 수치적으로 보다 유사하게 모사 할 수 있을 것으로 판단된다.