• Journal of the Korean Magnetics Society
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• v.11 no.3
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• pp.85-96
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• 2001

Experimental magnetization-temperature curves for melt-spun ribbons of amorphous alloys (Dy$\_$0.33/Fe$\_$0.67/)$\_$1-x/B$\_$x/(x=0 ,0.05, 0.1, and 0.15) and (Sm$\_$0.33/Fe$\_$0.67/)$\_$1-x/B$\_$x/(x=0, 0.01, 0.02, and 0.03) (in atomic fraction) are fitted with theoretical equations based on the mean field theory in order to calculate exchange couplings between constituent elements as a function of the B content. In the case of the DyFe$_2$-B system, the sign of the exchange coupling between Dy and Fe is negative, indicating that the magnetization direction of Dy is antiparallel to that of Fe. The sign of the other two couplings are positive indicating a parallel alignment. The exchange coupling between Fe ions are greatest, while that between Dy ions is negligible. In the case of the SmFe$_2$B alloys, the sign of all the couplings are positive, indicating ferromagnetic coupling between the spins. The exchange couplings between Fe ions, and Fe and Sm are comparable to each other, but they are much greater than that between Sm ions. The high exchange coupling between Fe and Sm, which is considered to occur indirectly, is rather unexpected, but it is considered to be unique characteristics of amorphous Sm-Fe alloys. In both alloy systems, the exchange coupling between Fe ions increases with increasing B content. and this may be explained by the increase of the Fe-Fe separation with increasing B content. The exchange coupling between Fe and RE also increases with increasing B content. As the B content increases, the magnetization decreases over the whole temperature range, and the Curie temperature also decreases.

• The Journal of Korean Society for Radiation Therapy
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• v.16 no.2
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• pp.43-61
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• 2004

Purpose : For qualify improvement in radiotherapy, it is important to set up and evaluate equipment (linac) accurately. In addition, technicians are needed to be fully aware of the equipment's detailed quality and its manual. Therefore, the result of ATP is evaluated and introduced, in order that the technicians are skilled by participating in quality assurance (QA) and understanding the quality of the equipment before clinical use. Method and Material : QA for LINAC 21EX (Varian, US) was done with suppliers its procedure was divided into radiation survey, mechanical test, radiation isocenter test, bean performance, dosimetry, and enhanced dynamic wedge and using X-omat film (Kodak), multidata, densitometer, and electrometer. QA of MLC (Millennium, 120 leaf) attached to LINAC and EPID (Portal vision) were done separately. Result : The leakage dose by survey meter was below the tolerance. In mechanical test, collimater, gantry, and couch rotation were less than 1mm, and the angles were ${\pm}0.1^{\circ}$ for digital and ${\pm}0.5^{\circ}$ for mechanical. The alignment test of the light field and crosshair were evaluated less than 1mm. The (a)symmetrical jaw field was less than ${\pm}0.5mm$. The radiation isocenter test using X-mat film was less than 1mm. The consistency of light field and radiation field was less than ${\pm}0.1mm$. PDD for photon energy was less than ${\pm}1\%$ and for electron energy of $90\%,\;80\%,\;50\%,\;and\;30\%$ were evaluated within the tolerance. Flatness for photon and electron energy was evaluated $2.3\%$ (tolerance $3\%$) and $3\%$ (tolerance $4.5\%$), respectively, and symmetry was $0.45\%$ (tolerance $2\%$) and $0.3\%$ (tolerance $2\%$), respectively. Dosimetry test for short term, MU setting, rep rate, and dose rate accuracy of photon and electron energy was within the tolerance depending on energy, MU, and gantry angle. Conclusion : Accuracy and safety for clinical use of Clinac 21EX was verified through customer acceptance procedure and the quality of the equipment was found out. These can reduce the difficulties in using the equipment. Furthermore, it is useful for clinically treatment of patients by technicians' active participations.

• Journal of Intelligence and Information Systems
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• v.21 no.1
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• pp.83-98
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• 2015

Many TV viewers use mainly portal sites in order to retrieve information related to broadcast while watching TV. However retrieving information that people wanted needs a lot of time to retrieve the information because current internet presents too much information which is not required. Consequentially, this process can't satisfy users who want to consume information immediately. Interactive video is being actively investigated to solve this problem. An interactive video provides clickable objects, areas or hotspots to interact with users. When users click object on the interactive video, they can see additional information, related to video, instantly. The following shows the three basic procedures to make an interactive video using interactive video authoring tool: (1) Create an augmented object; (2) Set an object's area and time to be displayed on the video; (3) Set an interactive action which is related to pages or hyperlink; However users who use existing authoring tools such as Popcorn Maker and Zentrick spend a lot of time in step (2). If users use wireWAX then they can save sufficient time to set object's location and time to be displayed because wireWAX uses vision based annotation method. But they need to wait for time to detect and track object. Therefore, it is required to reduce the process time in step (2) using benefits of manual annotation method and vision-based annotation method effectively. This paper proposes a novel annotation method allows annotator to easily annotate based on face area. For proposing new annotation method, this paper presents two steps: pre-processing step and annotation step. The pre-processing is necessary because system detects shots for users who want to find contents of video easily. Pre-processing step is as follow: 1) Extract shots using color histogram based shot boundary detection method from frames of video; 2) Make shot clusters using similarities of shots and aligns as shot sequences; and 3) Detect and track faces from all shots of shot sequence metadata and save into the shot sequence metadata with each shot. After pre-processing, user can annotates object as follow: 1) Annotator selects a shot sequence, and then selects keyframe of shot in the shot sequence; 2) Annotator annotates objects on the relative position of the actor's face on the selected keyframe. Then same objects will be annotated automatically until the end of shot sequence which has detected face area; and 3) User assigns additional information to the annotated object. In addition, this paper designs the feedback model in order to compensate the defects which are wrong aligned shots, wrong detected faces problem and inaccurate location problem might occur after object annotation. Furthermore, users can use interpolation method to interpolate position of objects which is deleted by feedback. After feedback user can save annotated object data to the interactive object metadata. Finally, this paper shows interactive video authoring system implemented for verifying performance of proposed annotation method which uses presented models. In the experiment presents analysis of object annotation time, and user evaluation. First, result of object annotation average time shows our proposed tool is 2 times faster than existing authoring tools for object annotation. Sometimes, annotation time of proposed tool took longer than existing authoring tools, because wrong shots are detected in the pre-processing. The usefulness and convenience of the system were measured through the user evaluation which was aimed at users who have experienced in interactive video authoring system. Recruited 19 experts evaluates of 11 questions which is out of CSUQ(Computer System Usability Questionnaire). CSUQ is designed by IBM for evaluating system. Through the user evaluation, showed that proposed tool is useful for authoring interactive video than about 10% of the other interactive video authoring systems.

• Journal of Plant Biotechnology
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• v.29 no.3
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• pp.161-170
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• 2002

For the hairy root of Panax ginseng, we have got mass spectrums from MALDI/TOF/MS analysis and Tandem mass spectrums from ESI/Q-TOF/MS analysis. While mass spectrum provides the molecular weights of peptide fragments digested by protease such as trypsin, tandem mass spectrum produces amino acid sequence of digested peptides. Each amino acid sequences can be a query sequence in BLAST search to identify proteins. For the specimens of animals or plants of which genome sequences were known, we can easily identify expressed proteins from mass spectrums with high accuracy. However, for the other specimens such as ginseng, it is difficult to identify proteins with accuracy since all the protein sequences are not available yet. Here we compared the mass spectrums and the peptide amino acid sequences with ginseng expressed sequence tag (EST) DB. The matched EST sequence was used as a query in BLAST search for protein identification. They could offer the correct protein information by the sequence alignment with EST sequences. 90% of peptide sequences of ESI/Q-TOF/MS are matched with EST sequences. Comparing 68% matches of the same sequences with the nr database of NCBI, we got more matches by 22% from ginseng EST sequence search. In case of peptide mass fingerprinting from MALDI/TOF/MS, only about 19% (9 proteins of 47 spots) among peptide matches from nr DB were correlated with ginseng EST DB. From these results, we suggest that amino acid sequencing using tandem mass spectrum analysis may be necessary for protein identification in ginseng proteome analysis.

• Restorative Dentistry and Endodontics
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• v.31 no.3
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• pp.147-152
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• 2006

The purpose of this study was to evaluate the influence of the AH-26 root canal sealer on the shear bond strength of composite resin to dentin. One hundred and forty four (144) extracted, sound human molars were used. After embedding in a cylindrical mold, the occlusal part of the anatomical crown was cut away and trimmed in order to create a flat dentin surface. The teeth were randomly divided into three groups; the AH-26 sealer was applied to the AH-26 group, and zinc-oxide eugenol (ZOE) paste was applied to the ZOE group. The dentin surface of the control group did not receive any sealer. A mount jig was placed against the surface of the teeth and the One-step dentin bonding agent was applied after acid etching. Charisma composite resin was packed into the mold and light cured. After polymerization, the alignment tube and mold were removed and the specimens were placed in distilled water at $37^{\circ}C$ for twenty four hours. The shear bond strength was measured by an Instron testing machine. The data for each group were subjected to one-way ANOVA and Tukey's studentized rank test so as to make comparisons between the groups. The AH-26 group and the control group showed significantly higher shear bond strength than the ZOE group (p<0.05). There were no significant differences between the AH-26 group and the control one (p>0.05). Under the conditions of this study, the AH-26 root canal sealer did not seem to affect the shear bond strength of the composite resin to dentin while the ZOE sealer did. Therefore, there may be no decrease in bond strength when the composite resin core is built up immediately after a canal filling with AH-26 as a root canal sealer.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.1-2
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• 2011

Hybrid rockets have lately attracted attention as a strong candidate of small, low cost, safe and reliable launch vehicles. A significant topic is that the first commercially sponsored space ship, SpaceShipOne vehicle chose a hybrid rocket. The main factors for the choice were safety of operation, system cost, quick turnaround, and thrust termination. In Japan, five universities including Hokkaido University and three private companies organized "Hybrid Rocket Research Group" from 1998 to 2002. Their main purpose was to downsize the cost and scale of rocket experiments. In 2002, UNISEC (University Space Engineering Consortium) and HASTIC (Hokkaido Aerospace Science and Technology Incubation Center) took over the educational and R&D rocket activities respectively and the research group dissolved. In 2008, JAXA/ISAS and eleven universities formed "Hybrid Rocket Research Working Group" as a subcommittee of the Steering Committee for Space Engineering in ISAS. Their goal is to demonstrate technical feasibility of lowcost and high frequency launches of nano/micro satellites into sun-synchronous orbits. Hybrid rockets use a combination of solid and liquid propellants. Usually the fuel is in a solid phase. A serious problem of hybrid rockets is the low regression rate of the solid fuel. In single port hybrids the low regression rate below 1 mm/s causes large L/D exceeding a hundred and small fuel loading ratio falling below 0.3. Multi-port hybrids are a typical solution to solve this problem. However, this solution is not the mainstream in Japan. Another approach is to use high regression rate fuels. For example, a fuel regression rate of 4 mm/s decreases L/D to around 10 and increases the loading ratio to around 0.75. Liquefying fuels such as paraffins are strong candidates for high regression fuels and subject of active research in Japan too. Nakagawa et al. in Tokai University employed EVA (Ethylene Vinyl Acetate) to modify viscosity of paraffin based fuels and investigated the effect of viscosity on regression rates. Wada et al. in Akita University employed LTP (Low melting ThermoPlastic) as another candidate of liquefying fuels and demonstrated high regression rates comparable to paraffin fuels. Hori et al. in JAXA/ISAS employed glycidylazide-poly(ethylene glycol) (GAP-PEG) copolymers as high regression rate fuels and modified the combustion characteristics by changing the PEG mixing ratio. Regression rate improvement by changing internal ballistics is another stream of research. The author proposed a new fuel configuration named "CAMUI" in 1998. CAMUI comes from an abbreviation of "cascaded multistage impinging-jet" meaning the distinctive flow field. A CAMUI type fuel grain consists of several cylindrical fuel blocks with two ports in axial direction. The port alignment shifts 90 degrees with each other to make jets out of ports impinge on the upstream end face of the downstream fuel block, resulting in intense heat transfer to the fuel. Yuasa et al. in Tokyo Metropolitan University employed swirling injection method and improved regression rates more than three times higher. However, regression rate distribution along the axis is not uniform due to the decay of the swirl strength. Aso et al. in Kyushu University employed multi-swirl injection to solve this problem. Combinations of swirling injection and paraffin based fuel have been tried and some results show very high regression rates exceeding ten times of conventional one. High fuel regression rates by new fuel, new internal ballistics, or combination of them require faster fuel-oxidizer mixing to maintain combustion efficiency. Nakagawa et al. succeeded to improve combustion efficiency of a paraffin-based fuel from 77% to 96% by a baffle plate. Another effective approach some researchers are trying is to use an aft-chamber to increase residence time. Better understanding of the new flow fields is necessary to reveal basic mechanisms of regression enhancement. Yuasa et al. visualized the combustion field in a swirling injection type motor. Nakagawa et al. observed boundary layer combustion of wax-based fuels. To understand detailed flow structures in swirling flow type hybrids, Sawada et al. (Tohoku Univ.), Teramoto et al. (Univ. of Tokyo), Shimada et al. (ISAS), and Tsuboi et al. (Kyushu Inst. Tech.) are trying to simulate the flow field numerically. Main challenges are turbulent reaction, stiffness due to low Mach number flow, fuel regression model, and other non-steady phenomena. Oshima et al. in Hokkaido University simulated CAMUI type flow fields and discussed correspondence relation between regression distribution of a burning surface and the vortex structure over the surface.

• Korean Journal of Optics and Photonics
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• v.28 no.3
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• pp.108-115
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• 2017

We report the assembly procedure and performance evaluation of a visible and near-infrared spectrometer in the wavelength region of 400-900 nm, which is later to be combined with fore-optics (a telescope) to form a f/2.5 imaging spectrometer with a field of view of ${\pm}7.68^{\circ}$. The detector at the final image plane is a $640{\times}480$ charge-coupled device with a $24{\mu}m$ pixel size. The spectrometer is in an Offner relay configuration consisting of two concentric, spherical mirrors, the secondary of which is replaced by a convex grating mirror. A double-pass test method with an interferometer is often applied in the assembly process of precision optics, but was excluded from our study due to a large residual wavefront error (WFE) in optical design of 210 nm ($0.35{\lambda}$ at 600 nm) root-mean-square (RMS). This results in a single-path test method with a Shack-Hartmann sensor. The final assembly was tested to have a RMS WFE increase of less than 90 nm over the entire field of view, a keystone of 0.08 pixels, a smile of 1.13 pixels and a spectral resolution of 4.32 nm. During the procedure, we confirmed the validity of using a Shack-Hartmann wavefront sensor to monitor alignment in the assembly of an Offner-like spectrometer.

• PNF and Movement
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• v.19 no.3
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• pp.423-433
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• 2021

Purpose: Proprioceptive neuromuscular facilitation (PNF) is a method for promoting functional movements by facilitating neuromuscular responses through the stimulation of proprioceptors in the body using spiral and diagonal patterns. Irradiation, a basic principle of PNF, is a phenomenon in which the muscle activity of a body part caused by resistance is increased or spread into muscles in other parts via their connected muscles. Resistance training can be divided by body alignment into closed and open chain exercises. Methods: In this study, 19 healthy men in their 20s and 30s were selected as subjects. They performed PNF hip flexion, abduction, and internal rotation motions on their dominant side in an open chain exercise posture in which the nondominant sole was away from the wall, and in a closed chain exercise posture in which the sole was fixed to the wall. The nondominant leg's muscle activity was measured while resistance was maintained with applied pressure at 0%, 25%, 50%, 75%, and 100% of the maximum muscle strength in the last range of motions. A two-way analysis of variance (ANOVA) was conducted for a comparative analysis of the contralateral leg's muscle activity according to the chain exercise postures and the intensity of resistance intensity during PNF hip flexion, abduction, and internal rotation. In addition, an independent sample T-test was conducted for a comparative analysis of each chain exercise posture according to the intensity of resistance. A one-way ANOVA and a Scheffe post-hoc test were also performed to analyze the contralateral leg's muscle activity according to the intensity of resistance in the closed and open chain exercise postures. Results: Results of the two-way ANOVA found that the gluteus medius and the biceps femoris had statistically significant differences in both the chain exercise postures and resistance intensity (p<0.05), and that the vastus medialis and the gastrocnemius did not exhibit statistically significant differences in the chain exercise postures (p>0.05) but showed statistically significant differences in resistance intensity (p<0.05). As a result of the independent sample T-test, the application of the PNF hip flexion-abduction-internal rotation pattern led to a statistically significant difference in the contralateral gluteus medius during the closed chain exercise posture (p<0.05). According to the results of the one-way ANOVA and the Scheffe post-analysis, statistically significant differences were observed in the gluteus medius at 50%, biceps femoris at 75%, vastus medialis at 100%, and gastrocnemius at 100% during the closed chain exercise posture based on a resistance intensity of 0% (p<0.05). In the open chain exercise posture, statistically significant differences were found in the gluteus medius at 50%, biceps femoris at 50%, and vastus medialis at 75% based on the resistance intensity of 0% (p<0.05). In the same posture, there was no significant difference in the gastrocnemius's resistance intensity (p>0.05). Conclusion: When the PNF leg pattern is applied, each muscle requires effective chain exercise postures and resistance intensity to generate the contralateral leg muscle's irradiation.

• Journal of the Korean Orthopaedic Association
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• v.53 no.6
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• pp.498-504
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• 2018

Purpose: To evaluate the clinical and radiological outcomes, and the complications of unicompartmental knee arthroplasty (UKA) using a fixed bearing prosthesis after 5-year follow-up. Materials and Methods: Twenty-six knees (25 patients) that underwent fixed bearing UKA between May 2003 and August 2011 were included. The subjects were 3 males (3 knees) and 22 females (23 knees), and the average age was 63.5 years. The preoperative diagnosis was osteoarthritis (23 knees) and osteonecrosis (3 knees). The mean follow-up duration was 67 months (from 60 to 149 months). The clinical evaluation included pre- and postoperative American knee society knee and function score, and range of motion. The radiology evaluation included standing antero-posterior, lateral view, and fluoroscopic film to analyze the postoperative alignment and osteolysis. Results: The mean American Knee Society knee score and function score were improved from 42.0 and 57.5 to 87.9 and 85.0, respectively (p<0.001). The mean preoperative and postoperative range of motion was $132.9^{\circ}$ and $132.5^{\circ}$, respectively. The mean femorotibial angle were varus $0.5^{\circ}$ preoperatively and valgus $2.2^{\circ}$ postoperatively. A radiolucent line was observed in 2 knees; one knee had a stable implant, while in the other knee, patellofemoral arthritis was identified during UKA. Diffuse pain of the knee joint with tenderness of the medial joint line was identified at the follow-up, so conversion to total knee arthroplasty was recommended. No other complications, such as osteolysis, infections, postoperative stiffness, and dislocation, were encountered. Conclusion: The midterm results of fixed bearing UKA were clinically and radiologically satisfactory.

• The korean journal of orthodontics
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• v.49 no.2
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• pp.124-136
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• 2019

Orthodontic treatment is more complicated when both soft and hard tissues must be considered because an impacted maxillary canine has important effects on function and esthetics. Compared with extraction of impacted maxillary canines, exposure followed by orthodontic traction can improve esthetics and better protect the patient's teeth and alveolar bone. Therefore, in order to achieve desirable tooth movement with minimal unexpected complications, a precise diagnosis is indispensable to establish an effective and efficient force system. In this report, we describe the case of a 31-year-old patient who had a labio-palatal horizontally impacted maxillary left canine with a severe occlusal alveolar bone defect and a missing maxillary left first premolar. Herein, with the aid of three-dimensional imaging, sequential traction was performed with a three-directional force device that finally achieved acceptable occlusion by bringing the horizontally impacted maxillary left canine into alignment. The maxillary left canine had normal gingival contours and was surrounded by a substantial amount of regenerated alveolar bone. The 1-year follow-up stability assessment demonstrated that the esthetic and functional outcomes were successful.