• Journal of Institute of Control, Robotics and Systems
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• v.16 no.4
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• pp.391-395
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• 2010

In our paper, we propose an asymmetric single-tracked wheel system, and describe its structure and the method for maintaining the length of a transformable track system. And the method is reducing the gap of lengths. Therefore, we propose an efficient structure for transforming and explain motions with kinematics. Our transformable shape single-tracked mobile system has an advantage to overcome an obstacle or stairs by the variable arms in the single unity track system. But we will make the variable shape of tracked system get a drive that has a force to stand against a wall. In this case, we can consider this system to a rigid body and have a notice that this single tracked system is able to get vary shape with the variable arm angle. Considering forces balance along x-axis and y-axis, and moments balance around the center of the mass we have. If this rigid body is standing against a wall and doesn't put in motion, the force of flat ground and the rigid body sets an equal by a friction. In the same way, the force of a wall and the rigid sets an equal by a friction.

• Fashion & Textile Research Journal
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• v.14 no.3
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• pp.347-362
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• 2012

The analysis results of the characteristics of children's clothes for school girls from the 2006S/S-2010S/S collections reveal that the most frequent type of item composition was 2'PS & 3'PS. T-shirts were the popular kind of item for upper garments and pants for lower garments. The major silhouettes were H and A line. The predominant neckline was U, which was followed by camisole and V. The major collar styles were stand-up and flat. Chromatic colors were used more than achromatic ones and after white the most popular colors were blue, pink, red, black, navy, and green. The dominant color scheme was a two-color or three-color scheme. The percentage of solid and patterned material garments was the highest and the most popular pattern was flowers. The most popular style of garment had no decorative detail that was followed by one-item, two-item, and three-item decoration. The major kinds of decorative detail were frills, pleats, and prints.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.4
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• pp.426-434
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• 2014

The research developed twin keel yacht for everyone which is able to stand erectly on mud flat without list and intended to commercialize the development product for popularization of west coast's marine leisure industry. Yacht's linear was utilized by "Blue Water21" has superior performance among the existing sailing yachts and twin keel model has been tested by calculation of mono keel's extent and its center of gravity. The result was that only 4 % of difference have been identified between mono keel and twin keel's hydrodynamic resistance which was smaller difference than predicted.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.2
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• pp.155-163
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• 2021

This design proposal research is meaningful as Jogakbo can retain the traditional value of the it's design as it becomes a contemporary design proposal. As a specific method of research, history was been investigated to find meaning and formative characteristics defined through prior research under the theme of Jogakbo. Ideas, such as silhouettes, details for design, and the making domestic and foreign designer examples were obtained. The fabric used for the works were recycled from past leather works. All materials are sheep skin. There were various processed surfaces used to avoid monotony. Jogakbo's cotton composition focused on free and radial patterns. The pattern was manufactured using a flat and 3D combination, and the selection of items was mainly made with a simple and light silhouette, so that Jogakbo's details, such as dresses, slip dress, and vests could stand out. Color is an important factor in Jogakbo. However, traditions which are relics of the times, do not need to be preserved in their original form. If changes are inherited with reasonable grounds and directions in line with the changing times, the significance and values are retained are sufficient. It is hoped that these design development studies will continue in the future so that our precious cultural heritage can continue to change and develop positively.

• The Journal of Korea Robotics Society
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• v.17 no.4
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• pp.438-446
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• 2022

In this paper, we propose an intelligent three-legged landing system that can maintain stability and level even on rough terrain than conventional four-legged landing systems. Conventional landing gear has the limitation that it requires flat terrain for landing. The 3-leg landing system proposed in this paper extends the usable range of the legs and reduces the weight, allowing the quadcopter to operate in various environments. To do this, kinematics determine the joint angles and coordinates of the legs of the two-link structure. Based on the angle value of the quadcopter detected via the IMU sensor, the leg control method that corrects the posture is determined. A force sensor attached to the end of the leg is used to detect contact with the ground. At the moment of contact with the ground, landing control starts according to the value of the IMU sensor. The proposed system verifies its reliability in various environments through an indoor landing test stand. Finally, in an outdoor environment, the quadcopter lands on a 20 degree incline and 20 cm rough terrain after flight. This demonstrates the stability and effectiveness of the 3-leg landing system even on rough terrain compared to the 4-leg landing system.

• Korean Journal of Remote Sensing
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• v.38 no.5_1
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• pp.571-585
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• 2022

As the threat of natural disasters such as droughts, floods, forest fires, and landslides increases due to climate change, social demand for high-resolution soil moisture retrieval, such as Synthetic Aperture Radar (SAR), is also increasing. However, the domestic environment has a high proportion of mountainous topography, making it challenging to retrieve soil moisture from SAR data. This study evaluated the usability of Sentinel-1 SAR, which is applied with the Artificial Neural Network (ANN) technique, to retrieve soil moisture. It was confirmed that the backscattering coefficient obtained from Sentinel-1 significantly correlated with soil moisture behavior, and the possibility of stand-alone use to correct vegetation effects without using auxiliary data observed from other satellites or observatories. However, there was a large difference in the characteristics of each site and topographic group. In particular, when the model learned on the mountain and at flat land cross-applied, the soil moisture could not be properly simulated. In addition, when the number of learning points was increased to solve this problem, the soil moisture retrieval model was smoothed. As a result, the overall correlation coefficient of all sites improved, but errors at individual sites gradually increased. Therefore, systematic research must be conducted in order to widely apply high-resolution SAR soil moisture data. It is expected that it can be effectively used in various fields if the scope of learning sites and application targets are specifically limited.

• Bulletin of the Korean Mathematical Society
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• v.50 no.4
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• pp.1109-1126
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• 2013

Let $\mathbb{M}^3_q(c)$ denote the 3-dimensional space form of index $q=0,1$, and constant curvature $c{\neq}0$. A curve ${\alpha}$ immersed in $\mathbb{M}^3_q(c)$ is said to be a Bertrand curve if there exists another curve ${\beta}$ and a one-to-one correspondence between ${\alpha}$ and ${\beta}$ such that both curves have common principal normal geodesics at corresponding points. We obtain characterizations for both the cases of non-null curves and null curves. For non-null curves our theorem formally agrees with the classical one: non-null Bertrand curves in $\mathbb{M}^3_q(c)$ correspond with curves for which there exist two constants ${\lambda}{\neq}0$ and ${\mu}$ such that ${\lambda}{\kappa}+{\mu}{\tau}=1$, where ${\kappa}$ and ${\tau}$ stand for the curvature and torsion of the curve. As a consequence, non-null helices in $\mathbb{M}^3_q(c)$ are the only twisted curves in $\mathbb{M}^3_q(c)$ having infinite non-null Bertrand conjugate curves. In the case of null curves in the 3-dimensional Lorentzian space forms, we show that a null curve is a Bertrand curve if and only if it has non-zero constant second Frenet curvature. In the particular case where null curves are parametrized by the pseudo-arc length parameter, null helices are the only null Bertrand curves.

• Journal of the Korean Society of Costume
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• v.45
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• pp.103-120
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• 1999

The purpose of the study is to show concretely the design features due to cltohes image after classifying the clothes image examining relations between clothes images and design factors. Samples of the study were 507 female university students. Materials of the study were 309 slide film using the spring and fall issues of magazines and catalogues in 1996 and 1997. SAS PC was used to analyze materials and finally priniciple component analysis the analysis by quantification theory 1. The results of the study were as follows. The most important images of clothes were fashion dignity activation and simplicity. In the relationship between the main image and item factor, one-piece jumper half-coat culotte skirt pantaloons and slim pants had an important effect on the fashion image while two-piece jacket, blouse, straight pants had an effect on the dignity image and three-pice, T-shirt, shirt-vest pantaloons normal pants culoote skirt and gather skirt strengthen active image. In the relationship between the main image and silhuette X-silhouette fitting upper and lower clothes upper clothes having waist line or hip bone length and mini-skirt were the factors that raisen fashion image. And in the A-, X-, Y-silhouette having normal fit upper clothes below the knee length skirt and the upper clothes below the hip line were main factors in dignity image. And H-silhouette big size sleeves mini-skirt the upper clothes below hip line were the factors that strengthened the active image. In the relationship between fashion image and detailed factors roll stand and sports collar set-in and shirt sleeves having 5-rate and long sleeves strengthened fashion image. And flat tailored collar boat and high nceckline and bow detail set-i sleeve had an important effect on the dignity image. And shirt collar boat and V-neckline shirt dolman and 7-rate sleeves were the factors that raise active image.

• Journal of Korea Society of Industrial Information Systems
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• v.13 no.4
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• pp.145-154
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• 2008

In this paper, we propose the pet robot control system using hand gesture recognition in image sequences acquired from a camera affixed to the pet robot. The proposed system consists of 4 steps; hand detection, feature extraction, gesture recognition and robot control. The hand region is first detected from the input images using the skin color model in HSI color space and connected component analysis. Next, the hand shape and motion features from the image sequences are extracted. Then we consider the hand shape for classification of meaning gestures. Thereafter the hand gesture is recognized by using HMMs (hidden markov models) which have the input as the quantized symbol sequence by the hand motion. Finally the pet robot is controlled by a order corresponding to the recognized hand gesture. We defined four commands of sit down, stand up, lie flat and shake hands for control of pet robot. And we show that user is able to control of pet robot through proposed system in the experiment.

• Journal of Korean Home Economics Education Association
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• v.21 no.3
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• pp.1-28
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• 2009

The purpose of this research was to provide the information needed for improving the elderly housing education and the elderly housing contents of Technology and Home Economics textbook. Thus, the elderly housing contents of current Technology and Home Economics textbook were categorized. Then, a total of 233 teachers were surveyed to examine their importance perception on the elderly housing contents. Elderly housing contents were grouped into S categories, each of which was named 'safety and safety management', 'room plan for the elderly', 'shrinking stage in family life cycle and dependency stage in housing life cycle','a house for 3-generation extended family', and 'universal design'. Teachers' importance perception was generally high for 'safety and safety management' and especially for 'safety and safety management' of bathroom(protection against slippery floor, safety bar, the appropriate position and height of shower, bathtub, and wash stand) ; the basic guidelines of 'room plan for the elderly'(emergency call, closely located bathroom, flat and non-slippery floor) ; the general guidelines during shrinking stage in family life cycle and dependency stage in housing life cycle'(protection equipments against safety accident, emergency call, flat and non-slippery floor) ; independent life among 3-generation extended family members(bathroom for the elderly, space plan for independent life among extended family members) ; the basic design guidelines of universal design(safety bar in bathroom, flat floor) and the guidelines of universal design which were especially helpful for wheelchair users(enough empty space in front of door and in corridor, wide door and corridor). Recommendations for the elderly housing education and the elderly housing contents of Technology and Home Economics textbook were that 'emergency call','safety bar in bathroom' and 'flat and non-slippery floor' were the most basic guidelines for elderly housing; that 'enough empty space in front of door and in corridor', 'wide door and corridor', 'low and wide steps', 'ramp for wheelchair users' and 'D-type or lever-type door handle' were most recommendable guidelines for universal design; that 'need for elderly housing', 'types of elderly housing', 'alternatives and choices of dependency stage in housing life cycle' and 'house plans for shrinking stage in family life cycle' were required guidelines for increasing elderly-only family.