• Journal of the Korean Society for Precision Engineering
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• v.24 no.9
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• pp.103-109
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• 2007

LCD (Liquid Crystal Display) is widely used electronic product. It needs too many processes such as PECVD (Plasma Enhanced Vapor Deposition), Sputtering, Photo-lithography, Dry etch. Each process is important but inspection process is more important because most companies emphasis on the six sigma. Recently, LCD inspection system is composed with inlet, inspector, outlet air pads. LCD is inspected on air pad which is shooting air from air hole. This paper studies on pad design of air bearing for LCD inspection to minimize LCD fluctuation. This design is able to reduce fluctuation and then satisfies CCD inspectional range. Also inspection pad needs to adequate stable area.

• Journal of the Korean Society of Radiology
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• v.16 no.6
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• pp.761-769
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• 2022

Pads with high dielectric materials have been used in a variety of applications to locally improve the field sensitivity and homogeneity of RF pulses in clinical MRI studies. In this study, we aimed to improve such pads in consideration of the practical problems associated with the application of actual clinical images. A high permittivity pad to increase the attenuated B1 field strength was fabricated and tested in 7T MRI. Sim4Life simulation and experimental results show stronger and relatively uniform B1 near field. In order to improve the image quality in the whole cerebellum, known as a region with low sensitivity, a guide was made to reduce the mechanical change of the pad. In order to improve the wearing comfort, the pad was designed by dividing it into upper and lower parts. The facial pad showed an overall signal increase effect in areas such as the turbinate in the nasal cavity. Signal increase was expected in areas such as the frontal lobe and eyes, but the effect was either insignificant or it was difficult to see the effect in the imaging protocol. In conclusion, this paper showed a cerebellar-optimized pad with an improved nasal signal while maintaining its effectiveness.

• The KSFM Journal of Fluid Machinery
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• v.12 no.5
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• pp.47-53
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• 2009

A rotordynamic and detailed stability analysis in accordance with API 617 standard were performed with a turbo-compressor, which is one of key rotating machinery in refinery, petroleum, and power plants. The system is composed of rotor shaft, impeller, sleeve hub, balance drum, and coupling hub. The rotor system is supported by tilting pad bearings, which has 5 pads and pad on loading condition. The rotordynamic analysis specified by API 617 includes the critical speed map, mode shape analysis, Campbell diagram, unbalance response analysis, and stability analysis. In particular, the specifications of stability analysis consist of a Level 1 analysis that approximates the destabilizing effects of the labyrinth seals and aerodynamic excitations, and Level 2 analysis that includes a detailed labyrinth seal aerodynamic analysis. The results of a rotordynamic analysis and stability analysis can evaluate the operating compressor health and can be utilized as a guide of its maintenance, repair and trouble solution.

• Journal of the Korean Society of Costume
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• v.54 no.4
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• pp.55-62
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• 2004

The ceremonies were roughly categorized into four： coming of age, marriage, funeral and ancestral worship. Among them, the funeral was a representative example to show ancestral worship. As it symbolizes the worship to ancestors, its procedure was complicated and formalized. It was undoubtedly certain that formalized mourning dresses and complicated table setting for sacrificial services to ancestors were burdens. Although what was symbolized by mourning dresses was different depending on the wearers purposes, it was thought that no clothing had such unusual symbolism as mourning dress. When the composition of mourning dress was examined, it was shown that Taoism, family relation of Confucianism or symbolic clothing system of Shamanism were combined. Mourning dress first represented the Confucian idea of ancestral worship. For the composition of clothing in which a shamanistic element was inherent, forms of birds were used to guide the dead soul to the other world. In cutting out mourning dress, opposite concepts of Yin and Yang, and closure and openness were used to show a harmony between heaven and the earth. Male and female were represented through sewing techniques. The period of observing the mourning period depended on the degree of kinship. The degree to which the clothing was loose indicated the degree of sadness and kinship. Load blocks and tear pads indicated the degree of sadness. In considering the above indicators, family relation and filial piety to ancestors had a great effect on the form and details of mourning dress. Shamanistic elements as well as Confucian ones were inherent in mourning dress, which resulted in the combination of Taoism and Confucianism.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.1
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• pp.41-51
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• 2005

Statement of problem. Anatomic landmarks have been used in the orientation of occlusal plane and the determination of vertical dimension for edentulous patients. Such as labial vestibules of anterior region and hamular notches, retromolar pads of posterior region are very useful anatomic landmarks for fabrication of occlusion rim because they are to be identified on master casts. Therefore, if average distances between landmarks of maxillae and mandible in dentate subjects are measured and applied, not only occlusal plane but also vertical dimension can be established initially. Purpose. The purpose of this study is to measure vertical distances between anatomic landmarks and to present a guide to the orientation of occlusal plane and the determination of vertical dimension of edentulous patients. Material and method. Upper and lower border-molded casts were made in 93 Korean dentulous subjects, mean age 25 years. Incisal edges of central incisors, bottoms of labial vestibules, hamular notches and the half level of retromolar pads were marked on casts. Measurements of vertical distances from incisal edge of central incisor to the bottom of labial vestibule, between upper and lower bottoms of labial vestibules, from hamular notch to retromolar pad and from hamular notch to the occlusal plane established by the incisal edge of maxillary central incisor and mesiopalatal cusps of both maxillary first molars were made on each cast. Results and conclusion. 1. The mean distance from the incisal edge of central incisor to the bottom of labial vestibule was 20.8mm(SD 1.7) on upper casts and 17.3mm(SD 1.4) on lower casts. 2. The mean distance between both bottoms of labial vestibules of upper and lower casts was 35.0mm(SD 2.7). 3 The mean distance from hamular notch to the half level of retromolar pad was 5.0mm(SD 1.3). 4. The mean distance from hamular notch to occlusal plane was 7.9mm(SD 1.5). 5. Distances from incisal edge of central incisor to labial vestibule on lower casts(P<0.01) and from hamular notch to retromolar pad(P<0.0001) were greater in male than in female.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2090-2100
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• 2011

Railway rail fastening system is the critical device which gives big influences to not only the vehicle driving stability and the orbit's structural stability against the impulsive load, but also the noise vibration and the ride comfort. As a part of the low-carbon green growth, the importance of the railroad industry is getting highlights on its excellent energy-efficiency and eco-friendliness. However, so far the Korea's domestic rail fastening system technology is not so good and the technical reliance to abroad is very heavy. In this study, we conducted comparative analysis on the rail fastening system with new and used one of the same type. And those systems are imported by Seoul Metro and are being used by it. With this basis, we developed the components and the materials and then, established the durability assessment methods appropriate to the Korean domestic circumstances. And through the reliability qualification test on the 7 parts of the rail fastening system, we've improved the reliability and guaranteed the 15 years of service lifetime. ($B_{10}Life15$) Establishment and standardization of Reliability Standard on the parts of the rail fastening system such as anti-vibration pads, guide-plate, screw spike made it possible to perform the internationally fair assessment. And it is thought that we can satisfy the manufactures' and consumers' needs of cost-cutting and qualification security by shortening of assessment period on rail fastening system.

• Journal of Information Technology Applications and Management
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• v.28 no.3
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• pp.59-75
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• 2021

This study aims to establish a foundation for autonomous driving on campus and communication of abundant university information in the HCI environment in a VR environment where college freshmen can freely travel around campus facilities. The purpose of this study is to develop a three-dimensional VR-style campus tour system to establish a media environment to provide abundant university information guidance services to freshmen in non-face-to-face situations. This study designed a three-dimensional virtual reality campus tour system to solve the problem of discontinuity in which VR360 filming space does not lead to space like reality, and to solve many problems of expertise in VR technology by constructing an integrated production environment of tour system. We aim to solve the problem of inefficiency, which requires a large amount of momentum in virtual space, by constructing a GUI that utilizes the motion of the field of view focus. The campus environment was designed as a three-dimensional virtual reality using a three-dimensional graphic design. In non-face-to-face situations, college freshmen freely transformed the HMD VR device, smartphone, FPS operation mode of the gyroscope sensor. The design elements of the three-dimensional virtual reality campus tour system were classified as ①Visualization of factual experiences, ②Continuity of space movement, ③Operation, automatic operation mode, ④Natural landscape animation, ⑤Animation according to wind direction, ⑥Actual space movement mode, ⑦Informatization of spatial understanding, ⑧GUI by experience environment, ⑨Text GUI by building, ⑩VR360, 3D360 Studio Environment, ⑪Three-dimensional virtual space coupling block module, ⑫3D360-3D Virtual Space Transmedia Zone, ⑬Transformable GUI(VR Device Dual Viewer-Gyro Sensor Full Viewer-FPS Operation Viewer) and an integrated production environment was established with each element. It is launched online (http://vautu.com/u1) by constructing a GUI for free driving mode and college information screens to adapt to college life for freshmen, and designing an environment that can be used simultaneously by current media such as PCs, Android, and iPads. Therefore, it conducted user research, held a development presentation, a forum on excellence in university innovation support projects, and applied it as a system on the website of a particular university. College freshmen will be able to experience university information directly from the web and app to the virtual reality campus environment.