• The korean journal of orthodontics
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• v.31 no.1 s.84
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• pp.15-24
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• 2001

In order to achieve a desirable tooth movement, it is of great importance to control the M/F ratio and to know the location of the center of resistance. The purpose of this study was to locate the center of resistance and the axis of rotation, and to estimate the stress distribution in the periodontal ligament with experimental model. After preparing a model of an upper canine with a simulated periodontal ligament and alveolar bone, the force and moment were applied. The tooth movement was traced using measuring device with LVDTs(Linear variable differential transformers) that can measure three dimensional tooth movement in real time. The results were as follows. 1. The location of center of resistance by transverse force was $29\%$ of root length measured from alveolar crest to apex regardless of force magnitude. The position of the center of resistance is more coronal than that of two-dimensional model($42\%$). 2. The center of resistance and the axis of rotation coincide when couple moment was applied. 3. As the magnitude of moment increases, tooth tends to extrude irrespective of the direction of the moment. 4. The relationship between location of force and axis of rotation (a x b = $49.6\;mm^2$) was obtained. A tooth movement can be predicted through this formula. 5. The centers of rotation by transverse force were plotted linearly.

• Journal of Navigation and Port Research
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• v.27 no.1
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• pp.41-48
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• 2003

The most great GPS is working on CNS(Car navigation System) and Personal terminal, but ocean has not been. First studied GPS is sailing to ship but We have been connivance that The ship is not need detail navigation. Lately, harbor facilities and transportation service in harbors are complication. We have need accurate ship navigation system. In this paper, author developed algorithms of ellipsoid conversion between WGS84 and BESSEL and develope algorithms of map projection between ellipsoid coordinate system, and plane cartesian system. Author used 3-parameter in covering ellipsoids and used TM and UTM projection in converting between ellipsoid and plane cartesian coordinate. And author analyzed errors through static surveying and dynamic surveying of GPS for proving accuracy of GPS sensor, Furthermore author analyzed deflection error of received position. Finally author developed real time ship navigation system using cheep GPS sensor.

• Journal of Digital Convergence
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• v.13 no.1
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• pp.297-304
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• 2015

Recently, the demand for a PRT(Personal Rapid Transit) system based on autonomous navigation is increasing. Accordingly, the applicability investigations of the PRT system on rail tracks or roadways have been widely studied. In the case of unmanned vehicle operations without physical guideways on roadways, to monitor the position of the vehicle in real time is very important for stable, robust and reliable guidance of an autonomous vehicle. The Global Positioning System (GPS) has been commercially used for vehicle positioning. However, it cannot be applied in environments as tunnels or interiors of buildings. The PRT navigation system based on magnetic markers reference sensing that can overcome these environmental restrictions and the vehicle dynamics model for its H/W configuration are presented in this study. In addition, the design of a control S/W dedicated for unmanned operation of a PRT vehicle and its prototype implementation for experimental validation on a pilot network were successfully achieved.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.6
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• pp.749-754
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• 2011

In this study, we propose the design of optimized pRBFNNs-based face recognition system using two-dimensional Image and ASM algorithm. usually the existing 2 dimensional face recognition methods have the effects of the scale change of the image, position variation or the backgrounds of an image. In this paper, the face region information obtained from the detected face region is used for the compensation of these defects. In this paper, we use a CCD camera to obtain a picture frame directly. By using histogram equalization method, we can partially enhance the distorted image influenced by natural as well as artificial illumination. AdaBoost algorithm is used for the detection of face image between face and non-face image area. We can butt up personal profile by extracting the both face contour and shape using ASM(Active Shape Model) and then reduce dimension of image data using PCA. The proposed pRBFNNs consists of three functional modules such as the condition part, the conclusion part, and the inference part. In the condition part of fuzzy rules, input space is partitioned with Fuzzy C-Means clustering. In the conclusion part of rules, the connection weight of RBFNNs is represented as three kinds of polynomials such as constant, linear, and quadratic. The essential design parameters (including learning rate, momentum coefficient and fuzzification coefficient) of the networks are optimized by means of Differential Evolution. The proposed pRBFNNs are applied to real-time face image database and then demonstrated from viewpoint of the output performance and recognition rate.

• 대한공업교육학회지
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• v.41 no.1
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• pp.108-127
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• 2016

We confront incessant choices in life. A person or a group stands at a crossroad continuously and make decisions under limited conditions in each time in order to achieve a goal. These series of processions are referred to as decision making and dominates our actions. Based on this view, the decision making is crucial and it secures its own position in school education as well as in real life. The purpose of this study is to develop decision making skills instructional model that can be applied to improve decision making skills in technological subjects. The components of decision making skills in technological education was problem recognition, problem identification, alternative production, alternative assessment, optimum selection, optimum evaluate. An instructional models for improvement of decision making skills in technology education and examination was designed according to the components of decision making skills in technological education. Depending on the components of decision making skills developed a teaching material to experience each step. And in the teaching material was to verify the improved decision-making skill. Accordingly, a decision making instruction model in technology is expected to contribute to enhance students' decision making skills.

• Journal of Life Science
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• v.23 no.2
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• pp.190-196
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• 2013

The sea squirt, Halocynthia roretzi, has experienced mass mortality due to softness syndrome. The identification of disease-induced genes can provide insights into the development of this syndrome. To identify the genes, we performed differentially expressed gene (DEG) analysis. The expression of the phosphoglycerate kinase (HrPGK) gene was significantly decreased in diseased sea squirts compared to normal ones. We confirmed the result of the DEG analysis through RT-PCR and real-time PCR. In addition, we detected single nucleotide polymorphisms at position -106 (A/T) and -254 (G/T) in the HrPGK gene promoter by genotyping analysis. At the -106 site of the HrPGK gene, the frequency of the AA allele in disease-resistant sea squirts was about two-fold higher than that of sensitive ones, and the frequency of the TT allele in the disease-resistant sea squirts was about six-fold lower. At the -254 site of the HrPGK gene, the frequency of the GT and the GG allele was approximately two-fold higher and two-fold lower, respectively, in the disease-resistant sea squirts compared to the disease-sensitive ones. Analysis of the relationship between the genotypic variation at the -106/-254 promoter and the expression of HrPGK mRNA showed that HrPGK mRNA expression was higher in the -106/-254 AA/GT genotype samples than in the -106/254 TT/GG genotype ones. These results show that sea squirts harboring the AA/GT genotype may have more resistance to mortality than the sea squirts with other genotypes.

• The Journal of Korean Medical History
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• v.26 no.1
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• pp.87-96
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• 2013

This study confirmed that a doctor named Lee, Seok-gan whose name has been widely known but whose real identity has remained unclear, was an active Confucian doctor in the 16th century. In addition, through the newly discovered "Daeyakbu" among his family line, writings, and relics that have been handed down in a family, this study looked into his medical philosophy and medicine culture. The author of "Ieseokgangyeongheombang"(Medical Book by Lee, Seok-gan(李石澗), Seok-gan is the same person as an active famous doctor Lee, Seok-gan(李碩幹, 1509-1574) in the 16th century. Such a fact can be confirmed through "Samuiilheombang", "Sauigyeongheombang" and the newly opened "Ieseokgangyeongheombang". Lee, Seok-gan was born in the 4th ruling year of king Jungjong (1509) and was active as a doctor until the 7th ruling year of king Seonjo(1547); his first name is Jungim with the pen name-Chodang, and he used a doctor name of 'Seokgan.' He was known as a divine doctor, and there have been left lots of anecdotes in relation with Lee, Seok-gan. Legend has it that Seokgan went to China to give treatment to the empress, and a heavenly peach pattern drinking cup and a house, which the emperor bestowed on Seokgan in return for his great services, still have remained up to the present. Usually, Seokgan interacted with Toegye Lee Hwang and his literary persons, and with his excellent medical skills, Seokgan once gave treatment to Toegye at the time of his death free of charge. His medical skills have been handed down in his family, and his descendant Lee, Ui-tae(around 1700) compiled a medical book titled "Gyeongheombangwhipyeon(經驗方彙編)". Out of Lee, Seok-gan's keepsakes which were donated to Sosu museums by his descendant family, 4 sorts of 'Gwabu'(writings of fruit trees) including "Daeyakbu" were discovered. It's rare to find a literary work left by a medical figure like this, so these discoveries have a deep meaning even from a medicine culture level. Particularly, "Daeyakbu" includes the typical "Uigukron". The "Uigukron", which develops its story by contrasting politics with medicine, has a unique writing style as one of the representative explanatory methods of scholars' position during the Joseon Dynasty; in addition, the distinctive feature of "Uigukron" is that it was created in the form of 'Gabu' other than a prose.

• Journal of Digital Convergence
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• v.17 no.10
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• pp.461-468
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• 2019

The aim of this study was to compare and analyse the national players between the winning games and the losing ones by classifying the GPS data measured in the competition. 27 players of Korean national team on field hockey had analysed to collect plenty of data by using GPS system in real time on 16 A-matches for this paper. The result was followed: First, it has revealed that the winning games showed that it had played a lot in the rest of the zone except for zone 1 and zone 5 from zone 1 to zone 6. Second, is has also shown that it had a significant differences into the distance between the winning games and the losing ones. Third, there were no significant differences between Low-speed zone (zone 1 to Zone 3) and High-speed zone (zone 4 to zone 6) into the distance but were a significant differences on the number of high-accelerations in a section of accelerations. Last, in the position-specific, it has shown a significant differences between a distance by the section and the acceleration frequency and the results showed that the difference between the low accelerations and high ones influenced positively related to the performance.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.2
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• pp.44-50
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• 2019

The underwater structures of landing pier are not easy to access and it is difficult to check the damage. Lately, typhoons and earthquakes have occurred frequently, which may cause damage to underwater structures of landing pier. In this study, to prevent collapse of underwater structures and to maintain systematically, the application method of FBG sensors and safety evaluation methods were studied. In order to confirm the application of the FBG sensor to the circular steel pipe used as a pile on the landing pier, we conducted laboratory tests and confirmed that the FBG sensor should be applied by welding. As a result of structural analysis of the landing pier structure, the optimal position of FBG sensor confirmed. The stresses on the dead load were calculated by structural analysis, the stresses on the live load were calculated by using the data obtained from the FBG sensor, and then the stress acting on the pile was calculated by adding the two stresses. The calculated stress was compared with the allowable stress to evaluate the safety of the pile. This study was carried out as a basic study to find a way to evaluate the safety of the landing pier in real time.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.3
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• pp.236-245
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• 2021

In this study, a drifting test using a experimental vessel (2,966 tons) in the northern waters of Jeju was carried out for the first time in order to obtain the fundamental data for drift. During the test, it was shown that the average leeway speed and direction by GPS position were 0.362 m/s and 155.54° respectively and the leeway rate for wind speed was 8.80%. The analysis of linear regression modes about leeway speed and direction of the experimental vessel indicated that wind or current (i.e. explanatory variable) had a greater influence upon response variable (e.g. leeway speed or direction) with the speed of the wind and current rather than their directions. On the other hand, the result of multiple regression model analysis was able to predict that the direction was negative, and it was demonstrated that predicted values of leeway speed and direction using an experimental vessel is to be more influential by current than wind while the leeway speed through variance and covariance was positive. In terms of the leeway direction of the experimental vessel, the same result of the leeway speed appeared except for a possibility of the existence of multi-collinearity. Then, it can be interpreted that the explanatory variables were less descriptive in the predicted values of the leeway direction. As a result, the prediction of leeway speed and direction can be demonstrated as following equations. Ŷ₁= 0.4031-0.0032X₁+0.0631X₂-0.0010X₃+0.4110X₄ Ŷ₂= 0.4031-0.6662X₁+27.1955X₂-0.6787X₃-420.4833X₄ However, many drift tests using actual vessels and various drifting objects will provide reasonable estimations, so that they can help search and rescue fishing gears as well.