• Journal of Ship and Ocean Technology
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• v.4 no.1
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• pp.21-27
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• 2000

The slamming force occurring in the free fall impact of cylindrical bodies on the water surface is analyzed in both compressible and incompressible stages. In the compressible phase the hydrodynamic analysis is carried on by the acoustic approximation, obtaining a closed form expression for the maximum impact force. The incompressible analysis is approached through and unsteady boundary element method to compute the free surface evolution and the slamming force on the body. A similar behavior seems to characterize the maximum slamming force versus a dimensionless mass parameter.

• 한국전산유체공학회:학술대회논문집
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• 2005.04a
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• pp.128-134
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• 2005

In the CFD area, the numerical analysis of high Mach number flow over a blunt-body poses many issues. Various numerical schemes have been developed to cover the issues, but the traditional schemes are still used widely due to the complexities of new schemes and intricacy of modifying the established codes. In the present study, the well-known Roe's FDS based on TVD-MUSCL scheme is used for the solution of very high Mach number three-dimensional flows posing carbuncle and non-physical phenomena in numerical analysis. A parametric study was carried out to account for the effects of the entropy fixing, grid configurations and initial condition. The carbuncle phenomena could be easily overcome by the entropy fixing, and the non-physical solution could be eliminated by the use of the modified initial condition regardless of entropy fixing and grid configurations.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.652-657
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• 2003

A wind-tunnel experiment is carried out to examine the applicability of a new passive device, wake disrupter, to flow over a model vehicle for drag reduction. The wake disrupter is a small-size rectangular body attached to a part of the trailing edge of the model vehicle, designed to perturb an essentially two-dimensional nature of wake. A pair of wake disrupter is mounted on the mid-span at the upper and lower trailing edges. From a parametric study about the size of wake disrupter, it is found that the optimum disrupter increases the base pressure by about 20%. Large eddy simulation is also conducted to confirm the experimental result, and shows that the wake is indeed disrupted by the present device.

• Biomaterials and Biomechanics in Bioengineering
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• v.5 no.1
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• pp.1-10
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• 2020

This paper investigated vibrational behavior of the osteon as bone unit in the different situations. This study can lead to increase our knowledge of our body. In this paper free vibration of the osteon with considering it as composite material has been studied. The effect of numbers of lamellae and radius of those on natural frequency of osteon are subtle; while thickness of lamellae have decreasing trend on natural frequency of osteon. The presence of nerve and blood in haversian canal change trend of natural frequency, absolutely. Using the nonlocal strain gradient theory(NSGT) leads to effectiveness of scale parameter on equations of motion and the obtained results. The governing equations are derived by Hamilton's principles. A parametric study is presented to examine the effect of various parameters on vibrational behaviour of osteon. The results can also be regarded as a benchmark in vibration analysis behavior of osteon as bone unite.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.362-369
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• 2005

In this paper, a research for the knowledge based configuration design software development of a train vehicle has been presented. Parametric design and knowledge based design concepts have been introduced for rapid design changes and analyses using a commercial CAD software, $CATIA^{/circledR}$ Knowledgeware module. Positions and dimensions of door, small window, large window, and number of seats were used as design parameters. It is crucial for train vehicle design because it enables rapid conceptual design by instant configuration changes. The results of this research can be used as one sub module of the multidisciplinary train vehicle design software and provide a basic data for rolling stock behavior and driver cab ergonomics of a train vehicle.

• Science of Emotion and Sensibility
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• v.19 no.2
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• pp.89-100
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• 2016

Inclusive design is increasingly gaining attention, as some people find using products difficult after becoming physically impaired, despite daily use. However, making inclusive products is a challenge for designers or companies, as a lack of knowledge and tools stems their low involvement in it. Developing inclusive design tools is thus needed. This study developed criteria to assess upper extremity capabilities corresponding to specific daily activities. A questionnaire survey was conducted among 58 physiatrists and orthopedists. Non-parametric statistics were employed and medians were adopted as representative scores in the assessment criteria based on normality and reliability test results, non-normal data, and strong reliability of respondents in ranking. Consequently, an assessment tool was developed with 14 criteria (divided into range of motion and strength) and capability scores between 0 and 100, which discerned the moderately impaired from the severely disabled and fully capable. Since the doctors agreed to adopt the criteria but assign numeric values, especially for mild impairments, their capability assessment perception was likely influenced by dichotomy. To compensate for these deficits, qualitative or ergonomic approaches are considered simultaneously.

• 한국HCI학회:학술대회논문집
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• 2008.02a
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• pp.439-444
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• 2008

The techniques, which locate example motions in abstract parameter space and interpolate them to generate new motion with given parameters, are widely used in real-time animation system for its controllability and efficiency However, as the dimension of parameter space increases for more complex control, the number of example motions for parameterization increases exponentially. This paper proposes a method that uses two different parameter spaces to obtain decoupled control over upper-body and lower-body motion. At each frame time, each parameterized motion space produces a source frame, which satisfies the constraints involving the corresponding body part. Then, the target frame is synthesized by splicing the upper body of one source frame onto the lower body of the other. To generate corresponding source frames to each other, we present a novel scheme for time-warping. This decoupled parameterization alleviates the problems caused by dimensional complexity of the parameter space and provides users with layered control over the character. However, when the examples are parameterized based on their upper body's spatial properties, the parameters of the examples are varied individually with every change of its lower body. To handle this, we provide an approximation technique to change the positions of the examples rapidly in the parameter space.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.4
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• pp.254-262
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• 2015

Parametric study on submerged body shape of an oscillating hemisphere point absorber was conducted to predict the optimal relation between radius and draft of the body. As an additional damping due to power takeoff system, the optimal damping same as wave radiation damping was applied to the PTO system to produce the maximum wave power. Body response spectrum and power spectrum were obtained for various peak frequencies on wave spectra. It was found that the maximum power can be generated when the peak frequency of available wave power was 20% greater than that of wave spectrum.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.7 no.2
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• pp.301-315
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• 2000

The main purpose of this study was to evaluate the effect of a Rhythmical Exercise Program(REP) on physiological functions such as muscle strength, blood pressure, pulse, flexibility and body fat in the elderly. The research employed a non-equivalent control group pre-post test quasi experimental design. REP consisted of 45 minutes of dance, 3 times a week for 10 weeks. The formulated hypothesis were examined using the non-parametric statistics; Wilcoxon Signed rank sum test and Mann-Whitney test. The results are as follows; 1. The upper muscle strength and lower muscle strength of the experimental group were significantly higher than those of the control group following the REP(P<.0 5). And the Period of REP affected the muscle strength; the longer the exercise period, the stronger the muscle strength became. 2. The systolic blood pressure of the experimental group was significantly lower than that of the control group following the REP(p<.05). But there was no significant difference in the diastolic blood pressure between the experimental and control groups. The period of REP affected only systolic pressure; the longer the exercise period, the lower the systolic pressure became. 3. There was no significant difference in heart rate between the experimental and control groups, following the exercise period. 4. The flexibility of the experimental group was significantly higher than those of the control group following the REP(p<.01). And the period of REP affected flexibility; the longer the exercise period, the higher the flexibility(p<.05) became. 5. There was no significant difference of body fat between the experimental and control groups. The body fat of the experimental groups was significantly lower only 10 weeks after exercise(p<.01). Based on these results, it is suggested that rhythmical exercise program improves muscle strength, systolic pressure, and flexibility in the elderly.

• Journal of Adhesion and Interface
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• v.13 no.1
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• pp.9-16
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• 2012

In order to describe external effects on the behavior of the adhesive tape, the semi-rigid body cylinder chain model for adhesive tape has been proposed as follows. Firstly the behavior of the tape is in detail investigated while it's being pulled off from the plate, and subsequently a relevant phenomenological model is designed. Then all the contributors affecting the force to peel out the tape from plate (hereafter, the pull out force) are clearly defined and their sensitivity analyses are made to set up the experimental reference condition, under which the angular dependence of the pull out force is measured in every $10^{\circ}$. The experimental data turn out to be in good agreement with the theoretical ones by our model within the measurement error, and the effects due to other factors are proved to be well explained from the phenomenological viewpoint. From these results, the concept of this study might be expected to be very useful for the test and evaluation of PSA types of adhesive tape.