• Transactions of the Society of Information Storage Systems
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• v.2 no.3
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• pp.208-213
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• 2006

The present state of the design of swing arm actuators for optical disc drives is to obtain the high efficient dynamic characteristics within a very compact volume. As a necessary consequence, the need of the small form factor (SFF) storage device has been arisen as major interests in the information storage technology. In this paper, we suggest the miniaturized swing arm type actuator that has high efficient dynamic characteristics for SFF optical disk drive (ODD). For the operating mechanism, it uses a tracking electromagnetic (EM) circuit for a focusing motion together. Moreover, due to the size constraint, the thermal stability of optical head is important. Therefore, the actuator is designed to emit the heat, which is generated by optical pick-up, along the actuator body easily. Initial model is designed based on the topology optimization method considering the thermal conductivity. Then, the structural parts of the actuator are modified to maintain the high sensitivity and to have wide control bandwidth by the design of experiments method (DOE) and new concept of decreasing mass and inertia. Finally, a swing arm type actuator for SFF ODD is suggested and its dynamic characteristics are verified.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.813-819
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• 2006

The state of the art for the design of swing ann actuators for optical disc drives is to obtain the high efficient dynamic characteristics, especially for the small size for the mobile information devices, It is affected by the need of consumers who wants the portable digital storage devices maintaining highly functional and removable characteristics of the optical disk drive (ODD). As a necessary consequence, the need of the small form factor (SFF) storage device has been considered as an important part in the information storage technology. In this paper. we suggest a new conceptual miniaturized swing arm type actuator that has high efficient dynamic characteristics as well as satisfies the sensitivity and the heat emission requirements for the SFF-ODD. It also uses a tracking electromagnetic (EM) circuit for a focusing motion. Due to the size constraint, the thermal problem of optical head arises; therefore, we design an efficiently heat emitted structure for the actuator.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.4
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• pp.641-650
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• 2008

In this study, seven models with distinctly different body types were researched and explanatory variables were reviewed. Review was done by using body measurements and the measurements of the appropriate bodice patterns in 1D, 2D, and 3D measurement methods in order to review the pattern making system and the equations for calculating the dimensions of the sleeve caps, which are readily available. Data on human bodies, which can be the criteria for each body part required for the new system for making sleeve cap part, were selected considering conditions such as items with a significantly high contribution rate from the results of regression analysis and the easiness of measurement. As a result of research, an explanatory variable required for the system for making sleeve caps with high general use was extracted. All items with the exception of the waist circumference and upper arm circumference were about the measurement of the form of human bodies, which were newly set in this study. As a result of this study, the equations for calculating the dimensions of each part of the sleeve caps showed distinct differences in comparison to the conventional system of construction.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.6
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• pp.864-875
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• 1999

This study was done to classify type os arms and to correspond these types with partial somatotype of upper body such as lateral views of upper body shapes of shoulder. The subjects of this study were female college students of twenties 58 anthropometric and photographic data were measured. The results were as follows : 1. Form the factor analysis arm girth/armscye size factor arm length factor the slope of lower arm, arm factor the curves of armscye the roundness of arm/shapes of shoulder the slope of upper arm factor were obtained. 2. By using factor scores 4 clusters of arm types were extracted. The characteristics of these clusters were projections of armscy slant of lower arm thick-set canelike. 3. Four types of arm were corresponded with the specified lateral views of upper body directions of shoulder slopes of shoulder.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.5
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• pp.1233-1246
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• 2018

With the proliferation of smart mobiles, disassembly techniques for position-independent code (PIC) composed of ARM architecture instructions in computer security are becoming more important. However, existing techniques have been studied on x86 architecture and are focused on solving problems of non-PIC and generality. Therefore, the accuracy of the collected address information is low to apply to advanced security technologies such as binary measurement. In this paper, we propose a disassembly technique that reflects the characteristics of PIC composed of ARM instructions. For accuratly collecting traceable addresses, we designed value-set analysis having symbol-form domain. To solve the main problem of disassembly, we devised a heuristic using the characteristics of the code generated by the compiler. To verify the accuracy and effectiveness of our technique, we tested 669 shared libraries and executables in the Android 8.1 build, resulting in a total disassembly rate of 91.47%.

• Composites Research
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• v.13 no.6
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• pp.39-46
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• 2000

Electrical discharge machining (EDM) cuts metal by discharging electric current across a thin gap between tool and workpiece. Electrical discharge wire cutting, a special form of EDM, uses a continuously moving conductive wire as an electrode, and is widely used for the manufacture of punches, dies and stripper plates. In the wire cutting process, the moving wire is usually supported by cantilever arm and wire guides. As the wire traveling speed has been increased in recent years to improve productivity, the vibration of the cantilever arm occurs, which reduces the positional accuracy of the machine. Therefore, the design and manufacture of the cantilever arm with high dynamic characteristics have become important as the machining speed increases. In this paper, the cantilever arm for guiding the moving wire was designed and manufactured using carbon fiber epoxy composite in order to improve the static and dynamic characteristics. Specimens for the composite cantilever arm were manufactured and tested to investigate the effect of the number of reinforcing plies and length fitted to steel flange on the load capacity. Also, the finite element analysis using layer and contact elements was performed to compare the calculated results with the experimental ones. From the results, the prototype of the composite cantilever arm for the electrical discharge wire cutting machine was manufactured and the static and dynamic characteristics were compared with those of the conventional steel cantilever arm.

• Transactions of the Society of Information Storage Systems
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• v.2 no.1
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• pp.21-25
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• 2006

The new multimedia information environment requires smaller optical data storage systems. However, one of the difficulties encountered in designing small form factor(SFF) optical pick-up is to emit the heat which is generated from laser diode(LD). Heat generated at the LD can reduce the optical performance of the system and the lifetime of LD. Therefore, it is important to include the thermal design in the design stage of SFF optical pick-up system for high performance and the longer lifetime of LD, and furthermore, to analyze the thermal characteristics of LD in detail micro heat transfer analysis is necessary. In the present study, micro heat transfer analysis was performed using the finite element method for the $28{\times}11{\times}2mm^3$ super slim swing-arm type optical pick-up actuator for Blu-ray disk. Two different materials were used for a swing-arm; a double layer polycarbonate/steel structure and a single aluminum structure.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.6
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• pp.1031-1040
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• 1997

This study was done to analyze the body surface developments of armhole area. The major conclusions of this study are: 1. The body surface developments showed the characteristics of expansion and contraction of body at armhole area. By arm movements, front armhole lines on the body surface developments of upper arm were slow going, but back armhole lines were full and round. As a whole, armhole line of the back torso was swollen outside especially at backarmpit point area, it seemed like a line of raglan sleeve. 2. Regression Analysis was carried out to adapt armhole line on the upper arm and upper body to bodice and sleeve pattern, following the axillary circumference line and chest breadth line changed to the basic pattern form. As the result, armhole lines of 90$^{\circ}$ and 135-180$^{\circ}$ movements deviated from those of standard posture. U-type, clear armhole curve of standard posture turned to V-type, slanting line by arm movements.

• Korean Journal of Applied Biomechanics
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• v.21 no.5
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• pp.573-584
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• 2011

The purpose of this study was to perform a kinematic analysis of the high jump techniques of the three men's medalists at the 2011 IAAF Championships in Daegu (August 27-September 4, 2011). In particular, a three-dimensional coordinates method was used to analyze the last three strides before touchdown, the touchdown techniques, and the movements after takeoff toward the bar. An analysis of the, data for the biomechanical characteristics of the world's best high jumpers could contribute to an improvement in the performance of a national high jumper. The first conclusion of the data analysis was that the arm movements of the gold medalist, J. Williams, had a single arm form, whereas the arm movements of the other medalists were a double arm form. Second, the difference in the knee joint angles upon touchdown and toe-off was $10^{\circ}$. Third, J. Williams achieved his maximum CM height after takeoff (1.26 m) using the maximum flexion of his knee joint. Fourth, the foot contact duration of A. Dmitrik (0.11 s) was the shortest among the medalists, and the ratio for his transformation of horizontal velocity to vertical velocity was the greatest (75.25%) among the three. Last, the maximum CM height of T. Barry was the greatest, and his foot contact duration was the longest.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.5
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• pp.468-474
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• 2002

In this paper a novel two-arm microstrip spiral antenna with a circular slot on the ground plane is presented. The proposed antenna structure is constructed in a planar form without a balun circuit and the radiation characteristics of conventional and eccentric spiral antennas are obtained simultaneously. The main beam direction is normal to the plane of the spiral for characteristic frequency band and the direction of the main beam moves linearly into $\theta$ and $\phi$ direction as the frequency increases.