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A Study on the Utilization of 4K/UHD Camera with 2/3" Sensor : Focused on Application of HD Lens (2/3" 센서를 활용한 4K/UHD 카메라 활용방안 연구 : HD 렌즈 활용을 중심으로)

  • Kim, Sang-il;Park, Sung-chul;Kwon, Soon-chul;Lee, Seung-hyun;Hamacher, Alaric
    • Journal of Digital Contents Society
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    • v.16 no.2
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    • pp.227-234
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    • 2015
  • Recently, there is more and more demand on broadcasting display environment that provides a sense of realism basically with high quality and high definition as in UHDTV, so various kinds of 4K cameras have been released. Super 35mm sensor 4K/UHD cameras being generally used can be usefully applied to the single camera-based system such as advertisements, dramas, nature documentaries, and culture programs. However, in the multicamera-based system such as entertaining programs, sports, and concerts, relay broadcasting may face limitations as there are restrictions of close-up or tight shots according to the distance. Besides, 4K lenses are not enough compared with the previous HD lenses' group, so there are limitations in camera photographing shots that have been realized in HD filming. Therefore, to complement this, the use of 2/3 inch sensor 4K/UHD cameras is being demanded, and it is also needed to use various lenses' groups to produce UHD image contents. Accordingly, this study used Grass Valley's LDX 4K/UHD camera to analyze its applicability based on the picture quality test at the use of HD lenses in 2/3 sensors and also the possibility of its efficient application.

Neural Activation in the Somatosensory Cortex by Electrotactile Stimulation of the Fingers: A Human fMRI Study

  • Seok, Ji-Woo;Jang, Un-Jung;Sohn, Jin-Hun
    • Journal of the Ergonomics Society of Korea
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    • v.33 no.5
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    • pp.395-405
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    • 2014
  • Objective: The aim of this study is to investigate 1) somatotopic arrangement of the second and third fingers in SI area 2) difference of neural activation in the SI area produced by stimulation with different frequencies 3) correlation between the intensity of tactile perception by different stimulus intensity and the level of brain activation measurable by means of fMRI. Background: Somatosensory cortex can obtain the information of environmental stimuli about "where" (e.g., on the left palm), "what" (e.g., a book or a dog), and "how" (e.g., scrub gently or scrub roughly) to organism. However, compared to visual sense, the neural mechanism underlying the processing of specific electrotactile stimulus is still unknown. Method: 10 right-handed subjects participated in this study. Non-painful electrotactile stimuli were delivered to two different finger tips of right hand. Functional brain images were collected from 3.0T MRI using the single-shot EPI method. The scanning parameters were as follows: TR and TE were 3000, 35ms, respectively, flip angle 60, FOV $24{\times}24cm$, matrix size $64{\times}64$, slice thickness 4mm (no gap). SPM5 was used to analyze the fMRI data. Results: Significant activations produced by the stimulation were found in the SI, SII, the subcentral gyrus, the precentral gyrus, and the insula. In all participants, statistically significant activation was observed in the contralateral SI area and the bilateral SII areas by the stimulation on the fingers but ipsilaterally dominant. The SI area representing the second finger generally located in the more lateral and inferior side than that of the third finger across all the subjects. But no difference in brain area was found for the stimulation of the fingers by different frequencies. And two typical patterns were observed on the relationship between the perceived psychological intensity and the amount of voxels in the primary sensory cortex during the stimulation. Conclusion: It was possible to discriminate the representation sites in the SI by electrotactile stimulation of digit2 and digit3. But we could not find the differences of the brain areas according to different stimulation frequencies from 3 to 300Hz. Application: The results of the study can provide a deeper understanding of somatosensory cortex and offer the information for tactile display for blinds.

OVERVIEW OF KSTAR INTEGRATED CONTROL SYSTEM

  • Park, Mi-Kyung;Kim, Kuk-Hee;Lee, Tae-Gu;Kim, Myung-Kyu;Hong, Jae-Sic;Baek, Sul-Hee;Lee, Sang-Il;Park, Jin-Seop;Chu, Yong;Kim, Young-Ok;Hahn, Sang-Hee;Oh, Yeong-Kook;Bak, Joo-Shik
    • Nuclear Engineering and Technology
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    • v.40 no.6
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    • pp.451-458
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    • 2008
  • After more than 10 years construction, KSTAR (Korea Superconducting Tokamak Advanced Research) had finally completed its assembly in June 2007, and then achieved the goal of first-plasma in July 2008 through the four month's commissioning. KSTAR was constructed with fully superconducting magnets with material of $Nb_3Sn$ and NbTi, and their operation temperatures are maintained below 4.5K by the help of Helium Refrigerator System. During the first-plasma operation, plasmas of maximum current of 133kA and maximum pulse width of 865ms were obtained. The KSTAR Integrated Control System (KICS) has successfully fulfilled its missions of surveillance, device operation, machine protection interlock, and data acquisition and management. These and more were all KSTAR commissioning requirements. For reliable and safe operation of KSTAR, 17 local control systems were developed. Those systems must be integrated into the logically single control system, and operate regardless of their platforms and location installed. In order to meet these requirements, KICS was developed as a network-based distributed system and adopted a new framework, named as EPICS (Experimental Physics and Industrial Control System). Also, KICS has some features in KSTAR operation. It performs not only 24 hour continuous plant operation, but the shot-based real-time feedback control by exchanging the initiatives of operation between a central controller and a plasma control system in accordance with the operation sequence. For the diagnosis and analysis of plasma, 11 types of diagnostic system were implemented in KSTAR, and the acquired data from them were archived using MDSpius (Model Driven System), which is widely used in data management of fusion control systems. This paper will cover the design and implementation of the KSTAR integrated control system and the data management and visualization systems. Commissioning results will be introduced in brief.

Software development for the visualization of brain fiber tract by using 24-bit color coding in diffusion tensor image

  • Oh, Jung-Su;Song, In-Chan;Ik hwan Cho;Kim, Jong-Hyo;Chang, Kee-Hyun;Park, Kwang-Suk
    • Proceedings of the KSMRM Conference
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    • 2002.11a
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    • pp.133-133
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    • 2002
  • Purpose: The purpose of paper is to implement software to visualize brain fiber tract using a 24-bit color coding scheme and to test its feasibility. Materials and Methods: MR imaging was performed on GE 1.5 T Signa scanner. For diffusion tensor image, we used a single shot spin-echo EPI sequence with 7 non-colinear pulsed-field gradient directions: (x, y, z):(1,1,0),(-1,1,0),(1,0,1),(-1,0,1),(0,1,1),(0,1,-1) and without diffusion gradient. B-factor was 500 sec/$\textrm{mm}^2$. Acquisition parameters are as follows: TUTE=10000ms/99ms, FOV=240mm, matrix=128${\times}$128, slice thickness/gap=6mm/0mm, total slice number=30. Subjects consisted of 10 normal young volunteers (age:21∼26 yrs, 5 men, 5 women). All DTI images were smoothed with Gaussian kernel with the FWHM of 2 pixels. Color coding schemes for visualization of directional information was as follows. HSV(Hue, Saturation, Value) color system is appropriate for assigning RGB(Red, Green, and Blue) value for every different directions because of its volumetric directional expression. Each of HSV are assigned due to (r,$\theta$,${\Phi}$) in spherical coordinate. HSV calculated by this way can be transformed into RGB color system by general HSV to RGB conversion formula. Symmetry schemes: It is natural to code the antipodal direction to be same color(antipodal symmetry). So even with no symmetry scheme, the antipodal symmetry must be included. With no symmetry scheme, we can assign every different colors for every different orientation.(H =${\Phi}$, S=2$\theta$/$\pi$, V=λw, where λw is anisotropy). But that may assign very discontinuous color even between adjacent yokels. On the other hand, Full symmetry or absolute value scheme includes symmetry for 180$^{\circ}$ rotation about xy-plane of color coordinate (rotational symmetry) and for both hemisphere (mirror symmetry). In absolute value scheme, each of RGB value can be expressed as follows. R=λw|Vx|, G=λw|Vy|, B=λw|Vz|, where (Vx, Vy, Vz) is eigenvector corresponding to the largest eigenvalue of diffusion tensor. With applying full symmetry or absolute value scheme, we can get more continuous color coding at the expense of coding same color for symmetric direction. For better visualization of fiber tract directions, Gamma and brightness correction had done. All of these implementations were done on the IDL 5.4 platform.

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Effects of Gradient Switching Noise on ECD Source Localization with the EEG Data Simultaneously Recorded with MRI (MRI와 동시에 측정한 뇌전도 신호로 전류원 국지화를 할 때 경사자계 유발 잡음의 영향 분석)

  • Lee H. R.;Han J. Y.;Cho M. H.;Im C. H.;Jung H. K.;Lee S. Y.
    • Investigative Magnetic Resonance Imaging
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    • v.7 no.2
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    • pp.108-115
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    • 2003
  • Purpose : To evaluate the effect of the gradient switching noise on the ECD source localization with the EEG data recorded during the MRI scan. Materials and Methods : We have fabricated a spherical EEG phantom that emulates a human head on which multiple electrodes are attached. Inside the phantom, electric current dipole(ECD) sources are located to evaluate the source localization error. The EEG phantom was placed in the center of the whole-body 3.0 Tesla MRI magnet, and a sinusoidal current was fed to the ECD sources. With an MRI-compatible EEG measurement system, we recorded the multi channel electric potential signals during gradient echo single-shot EPI scans. To evaluate the effect of the gradient switching noise on the ECD source localization, we controlled the gradient noise level by changing the FOV of the EPI scan. With the measured potential signals, we have performed the ECD source localization. Results : The source localization error depends on the gradient switching noise level and the ECD source position. The gradient switching noise has much bigger negative effects on the source localization than the Gaussian noise. We have found that the ECD source localization works reasonably when the gradient switching noise power is smaller than $10\%$ of the EEG signal power. Conclusion : We think that the results of the present study can be used as a guideline to determine the degree of gradient switching noise suppression in EEG when the EEG data are to be used to enhance the performance of fMRI.

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Measurement of two-dimensional vibration and calibration using the low-cost machine vision camera (저가의 머신 비전 카메라를 이용한 2차원 진동의 측정 및 교정)

  • Kim, Seo Woo;Ih, Jeong-Guon
    • The Journal of the Acoustical Society of Korea
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    • v.37 no.2
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    • pp.99-109
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    • 2018
  • The precision of the vibration-sensors, contact or non-contact types, is usually satisfactory for the practical measurement applications, but a sensor is confined to the measurement of a point or a direction. Although the precision and frequency span of the low-cost camera are inferior to these sensors, it has the merits in the cost and in the capability of simultaneous measurement of a large vibrating area. Furthermore, a camera can measure multi-degrees-of-freedom of a vibrating object simultaneously. In this study, the calibration method and the dynamic characteristics of the low-cost machine vision camera as a sensor are studied with a demonstrating example of the two-dimensional vibration of a cantilever beam. The planar image of the camera shot reveals two rectilinear and one rotational motion. The rectilinear vibration motion of a single point is first measured using a camera and the camera is experimentally calibrated by calculating error referencing the LDV (Laser Doppler Vibrometer) measurement. Then, by measuring the motion of multiple points at once, the rotational vibration motion and the whole vibration motion of the cantilever beam are measured. The whole vibration motion of the cantilever beam is analyzed both in time and frequency domain.

Seismic exploration for understanding the subsurface condition of the Ilwall-dong housing construction site in Pohang-city, Kyongbook (경북 포항시 일월동 택지개발지구의 지반상태 파악을 위한 탄성파탐사)

  • Seo, Man Cheol
    • Journal of the Korean Geophysical Society
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    • v.2 no.1
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    • pp.45-56
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    • 1999
  • Seismic refracrion and reflection surveys were conducted along an E-W trending track of 482 m long in Ilwall-dong, Pohang. End-on spread was employed as source-receiver configuration with 2 m for both geophone interval and offset. Seismic data were acquired using 24 channels at every shot fired every 2 m along the track. Refraction data were interpreted using equations for multi-horizontal layers. Reflection data were processed in the sequence of trace edit, gain control, CMP sorting, NMO correction, mute, common offset gathering, and filtering to produce a single fold seismic section. There are two layers in shallow subsurface of the study area. Upper layer has the P-wave velocities ranging from 267 to 566 m/s and is interpreted as a layer of unconsolidated sediments. Lower layer has P-wave velocities of 1096-3108 m/s and is interpreted as weathered rock to hard rock. Most of the lower layer classified as soft rock. Upper layer has lateral variations in both P-wave velocity and thickness. The upper layer in the eastern part of the seismic line is 3-5 m thick and has P-wave velocity of 400 m/s in average. The upper layer in the western part is 8-10 m thick and has P-wave velocity of 340 m/s in average. The eastern part is interpreted as unconsolidated beach sand, while the western part is interpreted as infilled soil to develop a construction site. Three fault systems of high angle are imaged in seismic reflection section. It is interpreted that the area between these fault systems are relatively safe. Large buildings should be located in the safe ground condition of no fault and footings should be designed to be in the basement rock of 3-10 m deep below the surface.

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Study of the error chsracteristics in a mirror loss measurement system using an exqonential decay metod (지수감쇠 기법을 이용한 반사경 손실측정 시스템의 오차특성 연구)

  • 조민식
    • Korean Journal of Optics and Photonics
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    • v.12 no.2
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    • pp.77-82
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    • 2001
  • Error characteristics of a mirror loss measurement system using an exponential decay method were studied, with the two samples having about 200-ppm-loss and 30-ppm-loss, respectively. In order to minimize the decay signal deviation from an exponential curve due to cavity length fluctuation, a data average method was tried. The data average method significantly improved the exponential curve fitting error of the decay signal, so that for a 6 decay signal data average the loss measurement error was reduced by about 2.4 times for the 200-ppm-loss mirror and 1.3 times for the 30-ppm-loss mirror compared with a single shot measurement. Day-to-day mirror loss repeatability error for the two samples was investigated. The repeatability error was measured to be about 5% for the 200-ppm-loss mirror and about 26.4% for the 30-ppm-loss mirror. Low decay signal average effect and high repeatability error in the low loss mirror measurement were explained with non-uniform spatial loss distribution of the sample and contamination from the environment, in addition to the error sources of the mirror loss measurement system itself. The influence of cavity length fluctuation and cavity length measurement error on the mirror loss measurement system performance was theoretically calculated. It confirmed that the requirement for the cavity length parameters was not so strict in the mirror loss measurement system of several ppm resolution. ution.

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A New Japanese Apricot (Prunus mume) Cultivar, "Okboseok" for High Yield (다수확 매실 신품종 "옥보석")

  • Jeong, Sang-Bouk;Kim, Yoon-Kyeong;Kang, Sam-Seok;Cho, Kwang-Sik;Choi, Jang-jeon
    • Korean Journal of Breeding Science
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    • v.41 no.4
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    • pp.534-538
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    • 2009
  • Japanese apricot (Prunus mume) "Okboseok" was released from a cross between "Nanko" and "Yoseibai" in 1993 at the Pear Research Station of National Institute of Horticultural and Herbal Science, Rural Development Administration. It was preliminarily selected in 2001 and named in 2006. It produces high yield with a flesh about average 88.3% of fruit, although the fruit size is small (approximately 14.0g). Horticultural and physiological harvest time of this cultivar is mid and late June respectively. It has single flowers with pink petal color and its flowering time is about 4 days later than that of "Nanko". Its fruit is tolerant to bacterial shot hole (Xanthomonas arboricola pv. Pruni) and pear scab (Venturia nashicola). "Okboseok" has abundant pollen grains (about 96 mg/100 flowers), thus it could be a pollinizer. To obtain stable yields, however, its compatibility with major cultivars is needed to be confirmed as pollinizer cultivar. "Okboseok" is recommended for being preserved in sugar and liquor.

Effect of Hypersonic Missiles on Maritime Strategy: Focus on Securing and Exploiting Sea Control (극초음속 미사일이 해양전략에 미치는 영향: 해양통제의 확보와 행사를 중심으로)

  • Cho, Seongjin
    • Maritime Security
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    • v.1 no.1
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    • pp.241-271
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    • 2020
  • The military technology currently receiving the most attention is the hypersonic missile. hypersonic is faster than the speed of sound or Mach 5+. The vast majority of the ballistic missiles that it inspired achieved hypersonic speeds as they fell from the sky. Rather than speed, today's renewed attention to hypersonic weapons owes to developments that enable controlled flight. These new systems have two sub-varieties: hypersonic glide vehicles and hypersonic cruise missiles. Hypersonic weapons could challenge detection and defense due to their speed, maneuverability, and low altitude of flight. The fundamental question of this study is: 'What effect will the hypersonic missile have on the maritime strategy?' It is quite prudent to analyze and predict the impact of technology in the development stage on strategy in advance. However, strategy is essential because it affect future force construction. hypersonic missiles act as a limiting factor in securing sea control. The high speed and powerful destructive power of the hypersonic missile are not only difficult to intercept, but it also causes massive ship damage at a single shot. As a result, it is analyzed that the Securing sea control will be as difficult as the capacity of sea denial will be improved geographically and qualitatively. In addition, the concept of Fortress Fleet, which was criticized for its passive strategy in the past, could be reborn in a modern era. There are maritime power projection/defence, SLOC attack/defence in exploiting sea control. The effects of hypersonic missiles on exploiting sea control could be seen as both limiting and opportunity factors.

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