• Journal of the Korean Society of Manufacturing Technology Engineers
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• 제5권2호
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• pp.29-37
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• 1996

High speed engines with high power are increasingly on demands and almost engines employ crankshafts Such problems as bending and torsional vibrations become the point at issue in crankshaft analysis and design. In this study to overcome the diffiiculty with the large amount of computation in finite element vibration analysis of a crankshaft, a reduction method based on influence coefficient and lumped parameter is presented. which reduces the computation amount effectively and can be used in vibrational analysis and design of any types of crankshafts Crank journal and pinparts are meodelled as elements with 6degrees of freedom per node. Crank web part is modelled using equivalent mass and stiffness matices . based up on lumped parameter and influence coefficient respectively to reduce total degrees of freedom considerablely. To confirm the scheme of the study the results are compared with the known data and they are coincident. Also a simple crankshaft is designed and manufactured for experiments. The calculated results using reduction method and the experimental results agree well The scheme of this study can be utilized in evaluation results agree well. The calculated result are compared with the known data and they are coincident. Also a simple crankshaft is designed and manufactured for experiments. The calculated results using reduction method and the experimental results agree well. The scheme of this study can be utilized in evaluation and development of high speed engine.

• Journal of the Korea Fashion and Costume Design Association
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• 제12권3호
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• pp.73-82
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• 2010

The purpose of this study is to help understanding of fashion trend since 2000 years, to play a guideline's role in the development on fashion designs study. The methods of this study are the study of academic literatures as well as practical study through expert investigation and analysis of case studies about actual works. Fashion trends since 2000 years are summarized classic, sporty, elegance, ethnic, natural, romantic, vintage, futurism by expert investigation and analysis of case studies about actual works. Image of fashion trends are abstracted that Classic image is harmony, moderation, accuracy, completeness, neatness, manish from keep an archetype to eliminate additional things, Sporty image is daily, active, enjoyment by the pursuit of a movement and freedom, Elegance image is feminine, grace from the tender moderated and feminity, Ethnic image is folkway, handicraft, vernacular to keep national character, local folkways and traditional ways. Natural image is nature, peaceful, purity, pastoral to the exclusion of artificiality and revert to natural, Romantic image is sensibility, fantastic, ornament, splendid from facing ideal world getting out of the reality, Vintage image is cozy, old, disorder, faden, freedom by expressing the flow of time and the mature beauty, Futurism image is future, experimental, avant-garde, man-made from positive perspective on future.

• Journal of Fashion Business
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• 제22권4호
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• pp.93-105
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• 2018

Using FDM 3D printing, yarn shape and composition were modeled and 3D printed with PLA and TPU filaments currently used for apparel. Based on this, mechanical characteristics were measured to determine 3D printing yarn according to type of filaments in the 3D printed output and deformation and recovery characteristics due to differences in structure type. As a result of examining tensile and shear characteristics of PLA and TPU 3D printing compiles, TPU overall was measured with significantly lower stress than PLA. This is due to high elasticity of TPU's character, revealing that it has better flexibility than PLA. In addition, during deformation due to external forces, the more freedom between the head and foot parts of the loop, and the lower the force associated with each other, the more flexible it is. TPU revealed that it was easier to tension and recovery from tensile deformation than PLA, indicating potential for clothing materials using 3D printing. If high-molecular materials, such as PLA flexibility, it is likely to provide some flexibility through development of styles, including degree of freedom in modeling. Based on this, we provide basic data for developing 3D printing textures that can be satisfied with textile for apparel.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제12권2호
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• pp.81-86
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• 2000

For on-shore structures, dynamic analysis becomes increasingly important as the water depth increases and the structural configuration becoines slenderer. In this study, an estimation method for equivalent three dimensional (30) hydrodynamic coefficients is introduced as a part of beam permutation technique development. The beam pemlUtation technique is being developed for obtaining an equivalent beam to a frame structure in order to reduce the degrees of freedom and thus the analysis time significantly. Two 3D structures are used in order to verify the obtained equivalent 3D hydrodynamic coefficients. Two commercial softwares, ANSYS and SACS, are used for the verification. The results of the present analysis are found to be satisfactory in comparison with those by the two softwares.

• Journal of the Korean Society of Clothing and Textiles
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• 제46권2호
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• pp.199-218
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• 2022

Considering increasing demand for improved waist protectors for the elderly, in this study we sought to design a waist protector that reflects the body characteristics, preferences, and satisfactions of the elderly. A survey conducted to investigate elderly satisfaction with existing waist protectors, as well as their preferences in product function, design, and characteristics, found that consumers are not satisfied with current waist protector offerings and would prefer protectors that allow greater freedom to perform physical activities and that are more easily accessible. Based on the survey, we developed a guideline on function, design, and characteristics, resulting in four new waist protector designs: A and B for men, and C and D for women. Significant preference differences according to gender were reflected in the designs. For example, designs for female waist protectors focused much more on improving tightness, size, freedom of movement, and easy attachment or detachment than designs for male waist protectors did. Evaluation of satisfaction with new designs suggests that new designs meet the satisfaction criteria of elderly consumers, who express willingness to purchase and use them.

• Journal of the Korean Society of Clothing and Textiles
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• 제46권5호
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• pp.910-926
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• 2022

Suitability for the human body, freedom to move and thermal insulation are important design considerations in military clothing. This study investigates the performance and wearer-satisfaction of the functional inner winter uniform currently used in Korea; it is hoped that our data can inform the development of a future version. Interviews were conducted, in which the participants suggested various improvements. The uniforms were mainly worn for guard duty or as daily attire in cold weather. The participants chose how many layers to wear according to the current situation, rather than sticking to the layering recommended in the manual. Layering choices did not significantly affect combat efficiency but were found to affect wearers' comfort. Wearers' satisfaction was found to depend on the convenience of the clothing, whether it was in the appropriate size, freedom to move and thermal insulation. Also, this study suggests a problem with the current size system, as the analysis of size distribution, across all sizes, the range of current production is insufficient to cover the demand.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1083-1086
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• 2003

Recently, the study on bearingless motors which integrate both motor and magnetic bearing function in one stator is very active, as many machines have high rotational speed, high precision, smaller size and lighter weight. In this paper, we propose a novel rotary actuator including function of axial bearing using Lorentz force as a preceding research for development of a bearingless motor. As using Lorentz force, this type has some merits such as the linearity of control force, freedom from flux saturation and high efficiency unlike conventional rotary actuators using a reluctance force. This type is cotrolled independently in levitation and rotational directions respectively. It shows by mathematical expression of levitation force and torque in the proposed rotary actuator. And also, the levitation force is generated by magnetic interaction between the magnetic materials and the rotational torque is generated by Lorentz force. Finally. for verification of this proposed system, a prototype is made and some experiments will be performed in the near future.

• Journal of the Korean Arthroscopy Society
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• 제2권1호
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• pp.77-79
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• 1998

Ganglion in the anterior cruciate ligament is quite rare finding at the time of knee arthroscopy. We experienced a 58 years old female pateint with a ganglion in the anterior cruciate ligamentwho complained gradual development of flexion contracture of left knee joint and treated with arthroscopic excision of ganglion resulted in freedom from flexion contracture of her knee joint.

• Journal of the Korea Institute of Military Science and Technology
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• 제22권4호
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• pp.517-526
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• 2019

In the present study, unsteady flows around a projectile ejected from an aircraft platform have been numerically investigated by using a three dimensional compressible RANS flow solver based on unstructured meshes. The relative motion between the platform and projectile was described by six degrees of freedom(6DOF) equations of motion with Euler angles and a chimera technique. Initial behavior of the projectile for varying conditions, such as roll and pitch-yaw command on the control surface of the projectile, flight Mach number, and platform pitch angle, was investigated. The ejection stability of the projectile was degraded as Mach number increases. In the transonic condition, the initial behavior of the projectile was found to be unstable as increase of platform pitch angle. By applying the command to control surfaces of the projectile, initial stability was highly enhanced. It was concluded that the proposed simulation data are useful for estimating the ejection behavior of a projectile in design phase.

• International Journal of Aeronautical and Space Sciences
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• 제11권3호
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• pp.175-183
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• 2010

The increased demand for a higher performing magnetic suspension and balance system (MSBS) resulted in an increase in costs for the efforts necessary for achieving an improved MSBS. Therefore, MSBS performance should be predicted during the design in order to reduce risk. This paper presents the modeling and simulation of an MSBS that controls 6-degree of freedom (DOF) of an aerodynamic body within the MSBS. Permanent magnets and electromagnets were modeled as coils, and this assumption was verified by experimental results. Finally, an MSBS simulator was developed, predicting that the MSBS is able to contain the model within a bounded region as well as measure external forces acting on the body during wind tunnel tests.