• The Journal of Advanced Prosthodontics
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• v.10 no.6
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• pp.401-407
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• 2018

PURPOSE. When performing an occlusal procedure, it is recommended that the patient should be sitting straight with the head in a natural position. An inappropriate mandibular position caused by an incorrect occlusal record registration or occlusal adjustment can result in damaged teeth and cause functional disorders in muscles and temporomandibular joints. The purpose of this study was to clarify the influence of horizontal cephalic rotation on mandibular position by investigating the three-dimensional positions of condylar and incisal points. MATERIALS AND METHODS. A three-dimensional jaw movement measurement device with six degrees of freedom (the WinJaw System) was used to measure condylar and incisal points. The subjects were asked to sit straight with the head in a natural position. The subjects were then instructed to rotate their head horizontally $0^{\circ}$, $10^{\circ}$, $20^{\circ}$, $30^{\circ}$, $40^{\circ}$, $50^{\circ}$and $60^{\circ}$ in the right or left direction. RESULTS. The results indicated that horizontal cephalic rotation made the condyle on the rotating side shift forward, downward, and toward the inside, and the condyle on the counter rotating side shift backward, upward, and toward the outside. Significant differences in deviations were found for angles of rotation higher than $20^{\circ}$. The incisal point shifted in the forward and counterrotating directions, and significant differences were found for angles of rotation higher than $20^{\circ}$. CONCLUSION. The mandibular position was altered by horizontal cephalic rotations of more than $20^{\circ}$. It is essential to consider the possibility of deviation of the mandibular position during occlusal procedures.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.11
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• pp.1518-1523
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• 2018

A method for designing a DDQYA fed by a CPW is proposed in this paper. The proposed CPW-fed DDQYA consists of two series-connected strip dipoles, a ground reflector, and a strip-pair director. Instead of the conventional microstrip feed line in which the signal line is located on the substrate opposite to the antenna, a CPW is used because CPW is located on the same side with the antenna, and so the fabrication is easy. The strip-pair director is composed of two horizontally-separated strips, and it is added above the second dipole to enhance the gain in the high frequency region. A prototype of the proposed CPW-fed DDQYA is fabricated on an FR4 substrate. The fabricated antenna has a frequency band of 1.66-3.38 GHz(68.3%) for a voltage standing wave ratio < 2, and measured gain ranges 5.0-7.3 dBi over a frequency band of 1.60-2.90 GHz.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.4
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• pp.103-112
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• 2019

This study proposes a system to control the bulging phenomenon occurring in the reinforced earth retaining wall and to evaluate the reliability of the system by field experiment. In this study, drainage facilities were not installed in order to induce reinforcement earth retaining wall bulging, and the bulging was induced by rainfall. The induced bulging displacement exceeded the horizontal displacement criterion during the construction of FHWA. The retaining wall block was drilled and grouting was performed by inserting the nail into the drilling hole. The wire mesh is installed on the reinforcing surface and the head of the nail is connected horizontally so that the blocks of the reinforcing earth retaining wall can be supported with each other. In order to protect the reinforcements, the reinforcement surface was closed with shotcrete and a measuring device was installed to detect the progress of the displacement. After the reinforcement, the bulging were not found to progress any more, confirming the reliability of the system.

• Korean Journal of Heritage: History & Science
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• v.42 no.1
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• pp.158-186
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• 2009

The Gossi Cave, Natural Monument 219, extends horizontally for 3,388m with 215m elevation. 620m of the horizontal cave length was opened to the public in 1974. The Gosu Cave, Natural Monument 256, also was opened the public for only 685m of the horizontal cave length, 1,700m, in 1976 in order to preserve its ecological cave environment. The surface of the speleothems in two caves have been turning black due to pollutants after the caves were opened to the public. The degrees of temperature, humidity and partial pressure of carbon dioxide in the caves were related the seasonal variation. Specially, the value of partial pressure of carbon dioxide($CO_2$) in the cave higher in the summer than any other seasons. The partial pressure of $CO_2$ continues to build in the summer because of exceed the self-purification limit in the caves. The value of $CO_2$ variation in the caves was mainly controlled by the amount of visitors. As a result, we have to controlled the amount of visitors to preserve the cave environment.

• Restorative Dentistry and Endodontics
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• v.44 no.1
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• pp.5.1-5.9
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• 2019

Objectives: The aim of this in vitro study was to evaluate the push-out bond strength of a novel calcium silicate-based root repair material-BIOfactor MTA to root canal dentin in comparison with white MTA-Angelus (Angelus) and Biodentine (Septodont). Materials and Methods: The coronal parts of 12 central incisors were removed and the roots were embedded in acrylic resin blocks. Midroot dentin of each sample was horizontally sectioned into 1.1 mm slices and 3 slices were obtained from each root. Three canal-like standardized holes having 1 mm in diameter were created parallel to the root canal on each dentin slice with a diamond bur. The holes were filled with MTA-Angelus, Biodentine, or BIOfactor MTA. Wet gauze was placed over the specimens and samples were stored in an incubator at $37^{\circ}C$ for 7 days to allow complete setting. Then samples were subjected to the push-out test method using a universal test machine with the loading speed of 1 mm/min. Data was statistically analyzed using Friedman test and post hoc Wilcoxon signed rank test with Bonferroni correction. Results: There were no significant differences among the push-out bond strength values of MTA-Angelus, Biodentine, and BIOfactor MTA (p > 0.017). Most of the specimens exhibited cohesive failure in all groups, with the highest rate found in Biodentine group. Conclusions: Based on the results of this study, MTA-Angelus, Biodentine, and BIOfactor MTA showed similar resistances to the push-out testing.

• The Research Journal of the Costume Culture
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• v.27 no.5
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• pp.433-448
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• 2019

Oversized fashion is again in the spotlight due to the influence of retro fashion. This has created new fashion trends with methods different from those of the past. This analysis examines recent trends by sorting these looks according to new and different methods of judging their appearance. A new categorization of the oversized look and its configurations has been created, one which separates "big" looks, partial changes, and layered looks. This research was based on historical review and previous studies. Three thousand one hundred thirty-six photos of oversized looks that have appeared in collections over the past five years were gathered, and their appearance was categorized according to type. The categorization results showed that big looks (55.1%) were most prevalent, followed by partial alterations (36.35%), and layered looks (8.45%). In comparison to prior oversized clothing production, new permutations of the "Big" look expanded the silhouettes of torso, shoulders, neckline and collar. Partial changes have expanded from the broadened shoulders of the 1980s. Today these styles expand the shoulders and armholes vertically or horizontally, which dramatically exaggerates the sleeves and collar. The layered look no longer simply features overlapping layers but takes the form of over-layering through cuts and insertions. Through such analysis it is clear that modern oversized looks break away from the simple expanded forms and production methods of the past. They now attempt to realize an exaggerated beauty of form regarding each clothing component and also maximize decorative effects through innovative drafting or sewing methods.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.2
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• pp.183-189
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• 2019

The purpose of this study was to investigate the changes of the position of the mental foramen according to age by using panorama of children with mixed and early permanent dentition. 180 panorama of 6 to 13-year-old boys and girls were analyzed and PiView(Infinitt, Korea) program was used. The horizontal position of the mental foramen was evaluated by the relative position of the teeth. The vertical position of the mental foramen was evaluated by the ratios between the distance from the center of the mental foramen to the inferior border of the mandible and the distance from to the alveolar crest to the inferior border of the mandible. The mental foramen was horizontally located in the anterior aspect of the second primary molar(premolar), and vertically slight below the half of mandibular body. As the age increased, it moved to the posterior and the downward and showed a significant correlation with age.

• The korean journal of orthodontics
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• v.49 no.3
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• pp.188-193
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• 2019

Objective: The aim of this finite element study was to clarify the mechanics of tooth movement in palatal en-masse retraction of segmented maxillary anterior teeth by using anchor screws and lever arms. Methods: A three-dimensional finite element method was used to simulate overall orthodontic tooth movements. The line of action of the force was varied by changing both the lever arm height and anchor screw position. Results: When the line of action of the force passed through the center of resistance (CR), the anterior teeth showed translation. However, when the line of action was not perpendicular to the long axis of the anterior teeth, the anterior teeth moved bodily with an unexpected intrusion even though the force was transmitted horizontally. To move the anterior teeth bodily without intrusion and extrusion, a downward force passing through the CR was necessary. When the line of action of the force passed apical to the CR, the anterior teeth tipped counterclockwise during retraction, and when the line of action of the force passed coronal to the CR, the anterior teeth tipped clockwise during retraction. Conclusions: The movement pattern of the anterior teeth changed depending on the combination of lever arm height and anchor screw position. However, this pattern may be unpredictable in clinical settings because the movement direction is not always equal to the force direction.

• Database Research
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• v.34 no.3
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• pp.124-136
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• 2018

There have been active research activities to use neural networks to analyze OCT images and make medical decisions. One requirement for these approaches to be promising solutions is that the trained network must be generalized to new devices without a substantial loss of performance. In this paper, we use a deep convolutional neural network to distinguish AMD from normal patients. The network was trained using a data set generated from an OCT device. We observed a significant performance degradation when it was applied to a new data set obtained from a different OCT device. To overcome this performance degradation, we propose an image normalization method which performs segmentation of OCT images to identify the retina area and aligns images so that the retina region lies horizontally in the image. We experimentally evaluated the performance of the proposed method. The experiment confirmed a significant performance improvement of our approach.

• Journal of The Geomorphological Association of Korea
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• v.24 no.3
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• pp.27-45
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• 2017

At the upper part of terrace deposits at Jeongdongjin area, there is a structure in which reddish brown and grayish white layers laying horizontally. Previous studies have reported the existence of these structures within the deposits and suggested the theoretical background related to the formation process. However, the analysis of physical properties and chemical composition such as particle size, classification, etc. of the materials constituting the reddish brown and grayish white layers is scarcely done. In this study, the physico - chemical properties of gray - white and reddish brown beds are investigated. The mean grain size of the particles was less than $4{\varphi}$ in both layers and the reddish brown layer was more coarse. The results shows that the sorting of the grayish white layer is better. The chemical composition of both layers shows that the average concentration of $SiO_2$, $Al_2O_3$ and $K_2O$ of the grayish white layer was higher than those of the reddish brown layer. The concentration of $Fe_2O_3$ of reddish brown lyaer was 3 times higher than those of the grayish white layer. The degree of chemical weathering (CIA) is 90 or so in both the reddish brown and grayish white layers, indicating a significant level of chemical weathering. In conclusion, reddish brown layers had been formed by the processes related to the migration of iron and the migration of water that induced aggregation after the formation of sediments (psudo-gleization). In this study area, a vertical layer of grayish white which cuts off horizontal reddish brown and grayish white color was found. The vertical layer or wedge similar to a ice-wedge or columnar structure that in a cold environment, and there is a difference in shape and size. The vertical layer appears to have occurred three or more cycles. The vertical layers begin to form at a certain height within the outcrop and descend downwards, which of course is difficult to see as directing certain times.