• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.309-313
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• 2006

Many researchers have studied on the lightness of automobile. These researches are such as a body shell, sub frame, fuel tank, engine etc. The transmission Part is a magnitude one in the aspect of weight. A drive shaft (propeller shaft) transmits the engine power to rear differential gear assembly. It is used in the compact car that is a single drive shaft. But in the case of long body cars such as SUV (Sports Utility Vehicle), truck and large vehicle, two or three divided drive shaft are used to prevent the vibration damage from a drive shaft that has been taken high torsion and rotation. This multi-divided drive shaft structure is so heavy because it is assembled by yoke, center bearing and solid spline axis. When the rear axle move up and down, the spline shaft adjust the variation of a length between the transmission and rear axle gearbox. In this paper, it is studied in the experimental method that is a bending vibration characteristic of slip in tube shaped propeller shaft. This type propeller shaft is developed to combine the spline axis with drive shaft and can be light in weight of transmission part.

• Journal of Powder Materials
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• v.20 no.6
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• pp.474-478
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• 2013

The most general photocatalyst, $TiO_2$ and $WO_3$, are acknowledged to be ineffective in range of visible light. Therefore, many efforts have been directed at improving their activity such as: band-gap narrowing with non-metal element doping and making composites with high specific surface area to effectively separate electrons and holes. In this paper, the method was introduced to prepare a photo-active catalyst to visible irradiation by making a mixture with $TiO_2$ and $WO_3$. In the $TiO_2-WO_3$ composite, $WO_3$ absorbs visible light creating excited electrons and holes while some of the excited electrons move to $TiO_2$ and the holes remain in $WO_3$. This charge separation reduces electron-hole recombination resulting in an enhancement of photocatalytic activity. Added Ag plays the role of electron acceptor, retarding the recombination rate of excited electrons and holes. In making a mixture of $TiO_2-WO_3$ composite, the mixing route affects the photocatalytic activity. The planetary ball-mill method is more effective than magnetic stirring route, owing to a more effective dispersion of aggregated powders. The volume ratio of $TiO_2(4)$ and $WO_3(6)$ shows the most effective photocatalytic activity in the range of visible light in the view point of effective separation of electrons and holes.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.2
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• pp.271-286
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• 2015

This study presented functional designs for development of functional compression wear for men in their forties based on body muscles as well as designed 2D patterns using 3D standard body form data of men in their forties. Patterns with an optimal stretch rate were proposed through a comfort evaluation. Different material was used for different areas such as the sports ability strengthening areas including body parts that often move for sports (such as the shoulders, abdomen and lower arm), areas that require ventilation for perspiration (such as the chest and back center, and armpits), and stable form areas (such as the chest, waist and elbows). The front and back surface areas of the developed pattern was an average 102.4% size compared to the body surface area. The results indicated that the 90% reduction pattern showed changes in pressure value according to area of movement, had the best breathability when worn, and had the best, most comfortable fit compared to the other subjects. The clothing pressure values of the pattern were around 22.1-23.4mmHg for the arm area (which has a big movement range and has many muscles) and 10.4-11.8mmHg for chest and abdomen areas related to major organs and breathing, indicating appropriate clothing pressure. A compression wear top pattern with pressure appropriate to the target age range and excellent appropriateness for the body form will be developed for men in their forties. A study method will be proposed to develop design technology for ergonomic compression wear tops with excellent fit and comfort.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.401-414
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• 2012

Distribution pattern and fishing conditions of sandfish, Arctoscopus japonicus in the East Sae were explored using catch and catch per unit effort (CPUE) by eastern sea Danish seine and coastal gill net fisheries from 2004 to 2008. A. japonicus was one of major target species for the eastern sea Danish seine and coastal gill net fisheries in the East Sea, which were caught from April to October for the eastern Danish seine, and from October to December for the coastal gill net, respectively. In recent, the distribution and centroid of fishing ground moved northward, as seawater temperature increased. The species spawned in the coastal areas of Gangwon, northern East Sea, during winter, started to move to deeper water after spawning from spring, extended widely from Gangwon to Ulsan, southern East Sea, during summer, and migrated back to the spawning ground off Gangwon during autumn.

• Journal of the Ergonomics Society of Korea
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• v.35 no.6
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• pp.493-501
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• 2016

Objective: This study analyzes the effect of angle conditions of rehabilitation equipment used for supporting hemiplegic patients on their rehabilitation training for standing action. The study was performed by adjusting the rear angle of seat inclination through a motion analysis. Background: Owing to a loss of muscle rigidity and degradation of muscle control ability, hemiplegic stroke patients suffer from asymmetrical posture, abnormal body balance, and degraded balance abilities due to poor weight-shifting capacity. The ability to shift and maintain one's weight is extremely essential for mobility, which plays an important role in our daily life. Thus, to improve patients' ability to maintain weight evenly and move normally, they need to undergo orthostatic and ambulatory training. Method: Using a motion analysis system, knee movements on both hemiplegic side and non-hemiplegic side were measured and analyzed in five angles ($0^{\circ}$, $10^{\circ}$, $30^{\circ}$, $50^{\circ}$, $70^{\circ}$) while supported by the sit-to-stand rehabilitation equipment. Results: The knee movements on both sides increased as the angle increased in angle support interval to support a hemiplegic patient's standing up position. In standing up interval, a hemiplegic patient's knee movement deviations on both sides decreased, and the movement differences between hemiplegic and non-hemiplegic legs also decreased as the angle increased. Conclusion: The results of this study showed that the rehabilitation effectiveness increases as the angle increases, leading to a balanced standing posture through the decrease of movement difference between hemiplegic and non-hemiplegic sides and an improved standing up ability through the increase of knee movement on both sides. However, angles higher than $50^{\circ}$ didn't provide a significant effect. Therefore, a support angle under $50^{\circ}$ was proposed in this study. Application: The results of this study are expected to be applicable to the design of sit-to-stand support equipment to improve the effectiveness of the rehabilitation process of hemiplegic patients.

• International Journal of Advanced Culture Technology
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• v.7 no.4
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• pp.208-221
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• 2019

The inference for this research was concentrated on client's data protection in cloud computing i.e. data storages protection problems and how to limit unauthenticated access to info by developing access control model then accessible preparations were introduce after that an access control model was recommend. Cloud computing might refer as technology base on internet, having share, adaptable authority that might be utilized as organization by clients. Compositely cloud computing is software's and hardware's are conveying by internet as a service. It is a remarkable technology get well known because of minimal efforts, adaptability and versatility according to client's necessity. Regardless its prevalence large administration, propositions are reluctant to proceed onward cloud computing because of protection problems, particularly client's info protection. Management have communicated worries overs info protection as their classified and delicate info should be put away by specialist management at any areas all around. Several access models were accessible, yet those models do not satisfy the protection obligations as per services producers and cloud is always under assaults of hackers and data integrity, accessibility and protection were traded off. This research presented a model keep in aspect the requirement of services producers that upgrading the info protection in items of integrity, accessibility and security. The developed model helped the reluctant clients to effectively choosing to move on cloud while considerate the uncertainty related with cloud computing.

• Korean Journal of Agricultural Science
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• v.23 no.2
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• pp.227-232
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• 1996

It is a tedious job to handle seedling trays in a green house with human hands because of their fluctuation when they are moving. A robotic gripper for handling a seedling tray has been developed., which has two fingers consisting of the vertical and horizontal bars. The maximum deflections at the center of the seedling trays were measured with various lengths of the horizontal bars. The length of 250 mm was revealed to be optimal one, resulting less than 15 mm deflection with a $540{\times}270mm$ seedling tray, which was acceptable for a practical use. For this study a LM system was adopted to move the fingers. To validate this system the robotic gripper was installed on a Cartesian robotic manipulator and their performance was tested several times with great success. The robotic manipulator used in this study was a general one, so a special one for this robotic gripper needs to be developed in future.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.4
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• pp.511-518
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• 2007

This paper presents an efficient face recognition method by using both centroid shift and mutual information estimation of images. The centroid shift is to move an image to center coordinate calculated by first moment, which is applied to improve the recognition performance by excluding the needless backgrounds in face image. The mutual information which is a measurements of correlations, is applied to efficiently measure the similarity between images. Adaptive partition mutual information(AP-MI) estimation is especially applied to find an accurate dependence information by equally partitioning the samples of input image for calculating the probability density function(PDF). The proposed method has been applied to the problem for recognizing the 48 face images(12 persons * 4 scenes) of 64*64 pixels. The experimental results show that the proposed method has a superior recognition performances(speed, rate) than a conventional method without centroid shift. The proposed method has also robust performance to changes of facial expression, position, and angle, etc. respectively.

• Korean Institute of Interior Design Journal
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• v.16 no.4
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• pp.81-88
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• 2007

The research made a study of the spatial characteristics of $m\'{e}diath\'{e}ques$ based on the twelve case studies of the BMVRs constructed with the financial support of the government since 1992 in France. The $m\'{e}diath\'{e}que$ is the community center for local residents to collect information, to have relationship with others and to shape public opinions. Thus it should have easy accessibility, liberal flow plan and the diversity of the newest information. The architectural elements to offer these faculties are summarized as follows. Firstly, the $m\'{e}diath\'{e}que$ as the public facility should have the easy flow plan and the high recognition for visitors. Second, it should be the efficient space for both managers and visitors. thus, it should not need more managers or have the difficulty to move. Third, it should be planed to support the change of the form of information and the needs of the visitors. It, therefore, should have the wide space with no wall and divide the space by movable furnitures. Lastly, it should be the space with the natural light, and it does not need the special artificial lights like museums. It is considered that the planning of the $m\'{e}diath\'{e}que$ should be from the four principles. Additionally, the program of the $M\'{e}diath\'{e}que$ should reflect the each local traits.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.2
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• pp.195-201
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• 2016

An experimental study has been found the air guide grooves for reducing drag. When a bullet is fired and move in the air, the drag is generated. The vortex which is one of the types of drag hinders the movement of the bullet. To solve this phenomenon, cut a negative grooves that we are called the air guiding grooves at the back of bullet. The grooves bullet has identified that the drag compared to conventional ammunition(KM80 and K193) is reduced to 4.480 and 4.054 : 10 % through a Finite Analysis Program($Ansys^{TM}$). Even pressure center was retreating 0.72 % compared to a Bullet(KM80 and K193). Effect obtained with these results is the accuracy of the grooves bullet in a shooting test was improved by over 32 %(KM80: 2.86, air guide grooves : 1.94) compared to conventional ammunition(KM80 and K193). In addition, muzzle velocity is increased 73 m/s. This is expected to be extended the velocity and effective range of bullet. Also, the velocity of the grooves bullet is increased when moving in the air while the velocity of the bullet(KM80 and K193) is reduced. The gas ejected from the muzzle to be balanced and stable flight of the Bullet. Given these effects, we can reckon the air guide grooves have positive influence.