• Korean Journal of Applied Biomechanics
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• v.32 no.4
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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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• v.34 no.4
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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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• v.9 no.3
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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.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.1
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• pp.34-42
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• 2011

It's been reported that the global warming effect has invoked the ever increasing typhoon intensity and long-term sea level rise which jointly cause severe wave overtopping over breakwaters or shore dykes. A simple measure to cope with this undesirable change may be just to increase the crest height of the dykes and breakwaters. This is surely effective to prevent wave overtopping, but it also decreases the seaward visibility of coastal waterfront. In this paper, a dynamic deformable rubber membrane parapet which not only reduces wave overtopping in storm period but also secures seascapes in normal days is presented. Several optimal configurations of the parapet are proposed. Through numerical analyses using a nonlinear finite element model and hydraulic experiments, the air controlled expansion and contraction of the parapets, their behavior against wave overtopping and structural stability are investigated.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.385-392
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• 2005

The object of this study is to prove the quality and reliability of recycled aggregate concrete by finding a way to improve the durability of the material through the experiment on the accelerated carbonation, freezing and thaw, and drying shrinkage, analysing the influence on the durability to Promote more active use of recycled aggregate concrete. The result of study as follows. (1) Resistibility to the freeze and thaw of the recycled aggregate concrete showed relative dynamic modulus of elasticity over $90\%$ which is very good, and all cycles show $99.2{\~}91.0\%$ dynamic modulus of elasticity which is improved compared with the $97.5{\~}90.6\%$ relative dynamic modulus of elasticity of ordinary concrete made of broken stone. (2) Carbonated thickness of the recycled aggregate concrete and the normal concrete was similar or it appeared with the tendency which it diminishes more or less. (3) Length change rate in drying contraction of the recycled aggregate concrete made of the recycled aggregate was lower than the ordinary concrete made of the broken stone by $18.5{\~}3.9\%$ in all blending.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.18 no.2
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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.

• Korean Institute of Interior Design Journal
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• v.13 no.3
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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.

• Journal of Environmental Science International
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• v.25 no.6
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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.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.3
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• pp.121-135
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• 2011

We provide an economic evaluation model to help managers make reasonable decision for the investment in the appropriate type of cloud computing. Cloud computing can be classified into public, private and hybrid architecture and we evaluate their attractiveness using traditional NPV and real option methods. We conduct economic analysis by comparing traditional software delivery model with various types of cloud computing. The work compares each mode of cloud computing against each other using passive NPV and dynamic real-option method. For more objective and conservative evaluation of investment alternatives, we eliminate conventional benefits that are often subjective or hard to measure, and count only the reduction of investment cost and maintenance cost as benefit. We argue that hybrid and public cloud computing can be undervalued without their intrinsic options such as abandonment, expansion and contraction.

• Explosives and Blasting
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• v.22 no.4
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• pp.7-15
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• 2004

An explosion modeling technique was developed by using the spherical discrete element code, PFC3D, which can be used to model the dynamic stress wave propagation phenomenon. The modeling technique is simply based on an idea that the explosion pressure should be applied to a PFC3D particle assembly not in the form of an external force (body force), but in the form of a contact force (surface force). According to this concept, the explosion pressure is applied to the wall particles by the scheme of radius expansion/contraction of inner-hole particles. The output wall force is compared to the input hole pressure in every time step, and a correction routine is activated to control the radius multiplier of the inner-hole particles. A comparative blast simulation far a cement mortar block of $80\times90\times80mm$ was conducted by using the conventional explosion modeling method and the new one. The results of the simulation are presented in a qualitative fashion.