• Korean Journal of Applied Biomechanics
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• v.15 no.4
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• pp.169-179
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• 2005

In the 500m short track speed skating, the matter of who reaches the first corner first can important factor since each competitor races with all speed from the start to the first line. A filed study was attempted to kinematical estimation six female foreign skaters, who participated in the 500m female final round competition, and two Korea skates during the World Short track Skating Championship. The three dimensional motion analysis with DLT method was executed using four video cameras for analyzing the actual competition situation. In point of analyzing the actual competition situation, it is expected that skaters and coaches the effective informations, and the following conclusions are drawn; The elapsed time by phase in start motion of the foreign skaters appeared shorter those of Korea skaters, so the start training of Korea skaters should be strengthed. Also the displacement of C.G in the foreign skaters appeared shorter displacement than those of Korea skaters. Especially in the starting position, the foreign skaters are superior to Korea skaters in displacement of first(left) and next following stroke(right). The velocity of C.G and maximum velocity of skate blade of foreign skaters art faster than those of Korea skaters. And the foreign skaters show the superior early velocity change. Both of leaning body angle, and left and knee angle of the foreign skaters lead to positive point of having the propulsive force in the early starting position. Observing in the most prominent feature of foreign and Korea skaters in start phase, foreign skaters skate quickly the third stroke. These features of Korea skaters would appear disadvantage of location selection in entering the coner course.

• Journal of Powder Materials
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• v.25 no.1
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• pp.25-29
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• 2018

Porous Cu with a dispersion of nanoscale $Al_2O_3$ particles is fabricated by freeze-drying $CuO-Al_2O_3$/camphene slurry and sintering. Camphene slurries with $CuO-Al_2O_3$ contents of 5 and 10 vol% are unidirectionally frozen at $-30^{\circ}C$, and pores are generated in the frozen specimens by camphene sublimation during air drying. The green bodies are sintered for 1 h at $700^{\circ}C$ and $800^{\circ}C$ in $H_2$ atmosphere. The sintered samples show large pores of $100{\mu}m$ in average size aligned parallel to the camphene growth direction. The internal walls of the large pores feature relatively small pores of ${\sim}10{\mu}m$ in size. The size of the large pores decreases with increasing $CuO-Al_2O_3$ content by the changing degree of powder rearrangement in the slurry. The size of the small pores decreases with increasing sintering temperature. Microstructural analysis reveals that 100-nm $Al_2O_3$ particles are homogeneously dispersed in the Cu matrix. These results suggest that a porous composite body with aligned large pores could be fabricated by a freeze-drying and $H_2$ reducing process.

• Korean Journal of Ichthyology
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• v.20 no.1
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• pp.7-12
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• 2008

Study on spermatid and spermatozoon of a Korean endemic freshwater fish, Microphysogobio yaluensis, has been carried out by transmission electron microscope. Spermiogenesis involves conspicuous modifications intercelluar movement such as centrioles and mitochondria migration, nuclear depression and structural changes for instance chroatin condensation, excess of cytoplasm. The mature spermatozoa are similar to those of other cyprinids as follows: a spherical nucleus with a shallow nuclear fossa, a short midpiece containing several mitochondria and encircling the basal body of the flagellum. However there are some differences in the orientation of the centrioles,the number of the mitochondria and distribution of vesicles from other cyprinids. It could be concluded that the M. yaluensis spermiogenesis belongs to type 2, and its mature spermatozoon is charaterized by a unique feature which may provide a useful systematic character.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.2
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• pp.147-157
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• 2017

In recent years, Super-pixels have become very popular for use in computer vision applications. Super-pixel algorithm transforms pixels into perceptually feasible regions to reduce stiff features of grid pixel. In particular, super-pixels are useful to depth estimation, skeleton works, body labeling, and feature localization, etc. But, it is not easy to generate a good super-pixel partition for doing these tasks. Especially, super-pixels do not satisfy more meaningful features in view of the gestalt aspects such as non-sum, continuation, closure, perceptual constancy. In this paper, we suggest an advanced algorithm which combines simple linear iterative clustering with fuzzy clustering concepts. Simple linear iterative clustering technique has high adherence to image boundaries, speed, memory efficient than conventional methods. But, it does not suggest good compact and regular property to the super-pixel shapes in context of gestalt aspects. Fuzzy similarity measures provide a reasonable graph in view of bounded size and few neighbors. Thus, more compact and regular pixels are obtained, and can extract locally relevant features. Simulation shows that fuzzy similarity based super-pixel building represents natural features as the manner in which humans decompose images.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.7 no.1
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• pp.49-52
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• 1977

The authors had observed a case of cleidocranial dysostosis of 42 years old unmarried woman. The observation was founded upon roentgenogram of skull P-A view, orthopantomograph, cephalometric view, chest P-A view and wrist X-ray view. The patient gave a dwarfic impression with 145㎝ body height and concaved mandibular prognastic facial feature. The palate was narrowed and extremely high arched. The eruption state of teeth were extremely poor, only four teeth were erupted, composed of upper third molar and lower three deformed teeth. The skull P-A view of roentgenogram reveals overlying metopic suture, extends from the nasion to the sagittal suture, and the suture are delayed up to date and many wormian bones are formed. On the cephalometric view the maxilla is underdeveloped and produce the false mandibular prognathism. Twenty four impacted teeth can be detected by orthopantmograph, twelve in upper jaw and twelve in lower jaw. There are many supernumerary teeth, one in upper jaw and seven in lower jaw. On the chest P-A view, the clavicles are totally aplastic, but a vestige of clavicle is visible in the right side. On the wrist roentgenogram, the epiphyseal ossification of distal phalanx, mesial phalanx and proximal phalanx is delayed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.339-342
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• 2017

Geometric transform of an image is used to image correction. Ridid-Body, Simlilary transform, etc, many correction methods are exist in computer vision. Image warping is used to correction for image with perspective. To image warping I extracted 4 feature point about warping position. But It is difficult to extract 4 points accurately and warping result with these point is occurs error over 3 or 4 pixel at warping position. So I used template matching to extract 4 points correctly and selected repeatedly 2 points of 4 points because to confirm result correctly. positions of 2 points are changed in near of 3 by 3 pixel and warped each change. So I selected optimal 4 points with a error of less than 1 pixel and finally, warped image using optimal points. For this way is possible to obtain optimum result.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.1
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• pp.8-22
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• 2014

In the past few decades, CMOS logic technologies and devices have been successfully developed with the steady miniaturization of the feature size. At the sub-30-nm CMOS technology nodes, one of the main hurdles for continuously and successfully scaling down CMOS devices is the parametric failure caused by random variations such as line edge roughness (LER), random dopant fluctuation (RDF), and work-function variation (WFV). The characteristics of each random variation source and its effect on advanced device structures such as multigate and ultra-thin-body devices (vs. conventional planar bulk MOSFET) are discussed in detail. Further, suggested are suppression methods for the LER-, RDF-, and WFV-induced threshold voltage (VTH) variations in advanced CMOS logic technologies including the double-patterning and double-etching (2P2E) technique and in advanced device structures including the fully depleted silicon-on-insulator (FD-SOI) MOSFET and FinFET/tri-gate MOSFET at the sub-30-nm nodes. The segmented-channel MOSFET (SegFET) and junctionless transistor (JLT) that can suppress the random variations and the SegFET-/JLT-based static random access memory (SRAM) cell that enhance the read and write margins at a time, though generally with a trade-off between the read and the write margins, are introduced.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.262-270
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• 2004

Basic experiments were carried out using the THT-IV low-power Hall thruster to examine the influences of magnetic field shape and strength, and acceleration channel length on thruster performance and to establish guidelines for design of high-performance Hall thrusters. Thrusts were measured with varying magnetic field and channel structure. Exhaust plasma diagnostic measurement was also made to evaluate plume divergent angles and voltage utilization efficiencies. Ion current spatial profiles were measured with a Faraday cup, and ion energy distribution functions were estimated from data with a retarding potential analyzer. The thruster was stably operated with a highest performance under an optimum acceleration channel length of 20 mm and an optimum magnetic field with a maximum strength of about 150 Gauss near the channel exit and with some shape considering ion acceleration directions. Accordingly, an optimum magnetic field and channel structure is considered to exist under an operational condition, related to inner physical phenomena of plasma production, ion acceleration and exhaust plasma feature. A new Hall thruster was designed with basic research data of the THT-IV thruster. With the thruster with many considerations, long stable operations were achieved. In all experiments at 200-400 V with 1.5-3 mg/s, the thrust and the specific impulse ranged from 15 to 70 mN and from 1100 to 2300 see, respectively, in a low electric power range of 300~1300 W. The thrust efficiency reached 55 %. Hence, a large map of the thruster performance was successfully made. The thermal characteristics were also examined with data of both measured and calculated temperatures in the thruster body. Thermally safe conditions were achieved with all input powers.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.4C
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• pp.226-231
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• 2011

To improve the conventional illustrated fish book, this paper introduces the concept of an electronic illustrated fish book which applies IT techniques to the conventional one, and proposes the image retrieval for it. The image retrieval is a core technology of the electronic illustrated fish book and make it overwhelm the conventional one. Since fishes, even if the same kind, have different features in shape, color, and texture and the same fish can even have different features by its pose or environment at that time for taking a picture, the conventional image retrieval, that uses simple features in shape, color, and texture, is not suitable for the electronic illustrated fish book. The proposed image retrieval adopts detail shape features extracted from head, body, and tail of a fish and different weights are given to the features depending on their invariability. The simulation results show that the proposed algorithm is far superior to the conventional algorithm.

• Journal of Society of Preventive Korean Medicine
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• v.14 no.3
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• pp.77-92
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• 2010

Objectives : There has been little known about the Tibetan medicine in the society for Korean medicine. The aim of this study is to review the system of Tibetan medicine and compare with Korean medicine. Methods : The authors investigated several literatures that mentioned Tibetan medicine and organized in physiology, pathology, diagnostics, and treatment. And then, we interpreted the characteristics of Tibetan medicine as well as compared Tibetan medicine with Korean medicine. After that, we analyzed the commons and the differences, and also found out the meaning of Tibetan medicine. Results : The theory of Tibetan medicine is basically constituted of three elements of Lung, Tripa, and Peken in every parts of physiology, pathology, diagnostics, and treatment. Many organs of human body are compared to the fabrications of building. There is a detail explanation about the process of the development of fetus in Tibetan medicine. Tibetan medicine uses taking pulse in wrist, analysis of urine, watching of tongue, sperm, and menstruation, and etc. for diagnosis. In Tibetan medicine, regimen is prior to other treatments such as surgical treatment and medications. Conclusions : There is the oriental thought of '3' in Tibetan medicine, and esoteric buddhism is solved in Tibetan medicine. The anatomy and the diagnostics using urine, sperm, and menstruation have especially been developed in Tibetan medicine. Tibetan medicine emphasizes the feature of preventive medicine.