• Current Optics and Photonics
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• v.6 no.1
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• pp.51-59
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• 2022

Holographic display technology is one of the promising 3D display technologies. However, the large amount of computation time required to generate computer-generated holograms (CGH) is a major obstacle to the commercialization of digital hologram. In various systems such as multi-depth head-up-displays with hologram contents, it is important to transmit hologram data in real time. In this paper, we propose a rapid CGH computation method by applying an arraying of a down-scaled hologram with the multiplication of a shifted concave lens function array. Compared to conventional angular spectrum method (ASM) calculation, we achieved about 39 times faster calculation speed for 3840 × 2160 pixel CGH calculation. Through the numerical investigation and experiments, we verified the degradation of reconstructed hologram image quality made by the proposed method is not so much compared to conventional ASM.

• Development and Reproduction
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• v.23 no.1
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• pp.63-72
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• 2019

The head gap gene buttonhead (btd) is required for the patterning of head segments in the early Drosophila embryo. Mutant phenotypes of btd display a gap-like phenotype in which antennal, intercalary, mandibular and the anterior portion of the maxillary segments are eliminated. In agreement with the phenotypes, btd is expressed in a stripe covering the head segments at the blastoderm stage. During the early phase of the germband extension, btd is expressed in stripes with single segmental periodicity, which is required for the formation of the peripheral nervous system. In contrast to the key role of btd in Drosophila embryonic development, it has been suggested that Tribolium ortholog of btd (Tc-btd) is dispensable for embryonic head development. In order for better understanding of the requirement of Tc-btd in the early Tribolium embryo, we re-analyzed the expression patterns and functions of Tc-btd during embryonic segmentation. Tc-btd is expressed in segmental stripes at the stages of blastoderm and germband elongation. Up to 28.3% of embryos in which Tc-btd is knocked down displays the loss of antennal, mandibular and the pregnathal regions in the head, with abdominal segments being disrupted in the trunk. Our findings suggest that Tc-btd is required for the head and trunk development in the early Tribolium embryo.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.3
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• pp.925-932
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• 2018

Virtual reality seems to be the center of the next generation platform, which is founded on various engines that can easily make device progress and content. However, the interaction between virtual reality contents and users is thought of as relatively requiring technological advances. In this paper, we propose a technique to improve the interaction technique based on the case of Virtual Figure Model Crafting (VFMC) to analyze the problem of interaction caused by virtual reality contents. We introduced the concept of Head-Up Display (HUD) to present a more natural interaction method. The HUD is the digital visual interface of the aircraft. The advantage of HUD visual interface is to minimizes the user's visual movement by displaying the information of the scattered view to the forward direction of the pilot. In other words, we can reduce unnecessary left and right movements that make it is possible to expect an effect of reducing fatigue and increasing immersion.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.94-102
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• 2003

This paper describes the development and implementation for the SYMBOLGEN(SYMBOL GENerator) software. The SYMBOL-GEN software is for improving graphic processing speed and decreasing data communication load in ASC by genera ting and downloading off-line symbol file for HUD and MFD , which are the main display equipments in military aircraft. The SYMBOL-GEN is developed on PC using C++ language and MS Visual Studio 6.0 development tool. It is also designed to be modified and extended easily by introducing object-oriented software development technique.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.373-378
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• 2012

The purpose of this study was to develop an electric riding machine for cycle fitting to control riding posture easily, to measure frame size quantitatively, and to overcome disadvantages of the traditional systems. The electric riding machine consisted of actuator, load controller, and display & control unit. The actuator unit by BLDC(BrushLess Direct Current) motor drives the saddle height up and down, the crank forward and backward, the handlebar up and down, and the handlebar forward and backward. The load controller unit controls loads by Eddy current controller with electromagnet and aluminum circular plate. The display & control unit consisted of frame size controller and display panel which shows top tube length(485~663mm), head tube length(85~243mm), seat tube length(481~671mm), and seat tube angle($62.7{\sim}76.4^{\circ}$). The range of frame size control for developed electric riding machine did not have difference compared to traditional commercial systems, but quantitative and precise control with 0.1 mm length and $0.1^{\circ}$ angle was possible through digital measurement. Unlike traditional commercial systems, frame size control was possible during riding through motor driven method, thus fitting duration decreased. It is necessary for further improvement to have feedback from users. It is believed that developed electric riding machine can help to develop domestic fitting system.

• Journal of the Korean Society of Fashion and Beauty
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• v.5 no.4
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• pp.149-157
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• 2007

Hair style was mean of visual symbol that display position or wealth about human life. Also, have spoken for cultural value as human body plastic art that speak for the age. I wished to study about modeling of hair style and interrelationship of color by analyzing systematically laying stress on color through contest creation work consisted in beauty art congress. Urpose of this study is as following. First, examines domestic' outside great council work head change by era, and studies Hair Work's change in work head. Second, Hair Color's change that appear in domestic' outside contest work head studies effect that get in work. Method of study runs parallel literature study and supporting research, utilized domestic' outside literature, connection paper, magazine, picture data etc. To literature study, and work picture data examined laying stress on work that is choosesed picture dataworld beauty use association (OMC) data etc. that appear in domestic' outside beauty art magazine to examine closely specification and stability of beauty art game style and participates in domestic and world beauty art contest. In this study, domestic' characteristic, and effect that collar gets in work head of collar that collects outside contest participating in an athletic contest hair style by ($1981{\sim}$until present) by year and appears in contest work head and in work since analyzing study forward $2007{\sim}2008$ year direction of collar. First, stream of whole color of the 1980s Brown gave highlight color point partially to basis, and was consisted of creative style and do Gold base color on the whole in Hair by Night item. Second, various Hair color was popularized in the 199Os, and Tuton's color appeared in beauty art game work, and I contributed to improve technique that step-up gradation color appears and does technique to highlight in neon orange in creative style and Hair by Night item by entrance on the stage of neuter gender color.

• ETRI Journal
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• v.40 no.3
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• pp.366-375
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• 2018

Recently, techniques involving head-mounted displays (HMDs) have attracted much attention from academia and industry owing to the increased demand for virtual reality and augmented reality applications. Because HMDs are positioned near to users' eyes, it is important to solve the accommodation-vergence conflict problem to prevent dizziness. Therefore, holography is considered ideal for implementing HMDs. However, within the Nyquist region, the accommodation effect is limited by the space-bandwidth-product of the signal, which is determined by the sampling number of spatial light modulators. In addition, information about the angular spectrum is duplicated over the Fourier domain, and it is necessary to filter out the redundancy. The size of the exit-pupil of the HMD is limited by the Nyquist sampling theory. We newly propose a holographic HMD with an expanded exit-pupil over the Nyquist region by using the time-multiplexing method, and the accommodation effect is enhanced. We realize time-multiplexing by synchronizing a high-speed digital micromirror device and a liquid-crystal shutter array. We also demonstrate the accommodation effect experimentally.

• Journal of the Korea Safety Management & Science
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• v.15 no.3
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• pp.163-170
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• 2013

There are many pros and cons for whether smart glasses and watch would be further going technology or not beyond smart phone. What have to do domestically is to find acting ways to catch up with technological gap in short term basis through analyses and investigations in technological issues, patents profile, market forecast. In this paper, firstly we investigate and review technological issues and form factors of smart glasses and HMD, and secondly analyze technological tendency and identify their core technology and intension from global key player's patents analyses connected with smart glasses, and conclusively suggest technological prospects and it's countermeasures.

• The KSFM Journal of Fluid Machinery
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• v.16 no.2
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• pp.21-26
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• 2013

Super-cavitating vehicle which is operating under water speeds up to 100m/s. In this process super-cavitation around body reduces frictional resistance. This paper introduces experimental study on different width of suction path as there is a warhead in the torpedo. Hydraulic performances of turbopump at non-cavitating condition does not display a significant differences depending on different width of suction path. However, cavitation performance of each model shows obvious differences in the same condition of experience. In case of radial inlet, the value of critical NPSH(which indicates 3% head drop) increases about 20% in comparison of axial inlet.

• Journal of Positioning, Navigation, and Timing
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• v.5 no.3
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• pp.119-129
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• 2016

This paper presents an integrated navigation system for accurate navigation solution-based safety and convenience services in the vehicular augmented reality (AR)-head up display (HUD) system. For lane-level guidance service, especially, an accurate navigation system is essential. To achieve this, an inertial navigation system (INS)/global positioning system (GPS)/vision/digital map (IGVM) integrated navigation system has been developing. In this paper, the concept of the integrated navigation system is introduced and is implemented based on a multi-model switching filter and vehicle status decided by using the GPS data and inertial measurement unit (IMU) measurements. The performance of the implemented navigation system is verified experimentally.