• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.6
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• pp.71-75
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• 2006

The application of focused ion beam (FIB) technology in micro/nano machining has become increasingly popular. Its usage in micro/nano machining has advantages over contemporary photolithography or other micro/nano machining technologies such as small feature resolution, the ability to process without masks and being accommodating for a variety of materials and geometries. The target of this paper is the analysis of FIB sputtering process according to tilt angle, dwell time and overlap for application of 3D micro and pattern fabrication and to find the effective beam scanning conditions using Taguchi method. Therefore we make the conclusions that tilt angle is dominant parameter for sputtering yield. Burr size is reduced as tilt angle is higher.

• ETRI Journal
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• v.38 no.6
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• pp.1124-1134
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• 2016

The tone reservation method is one of the most effective pre-distortion methods for peak-to-average power ratio reduction in orthogonal frequency division multiplexing (OFDM) systems. Its direct application to OFDM systems with offset quadrature amplitude modulation (OQAM) is, however, not effective. In this paper, two novel TR-based methods are proposed, specifically designed for OFDM/OQAM systems by taking into consideration the overlapping nature of OQAM signals. These two methods have different approaches to the generation of the peak-cancelling signal. The first one (overlapped scaling tone reservation) generates the peak-cancelling signal using a least squares approximation algorithm with possible adjacent symbol overlap; the second one (multi-kernel tone reservation) generates the peak-cancelling signal by using multiple impulse-like time domain kernels. It is shown by simulation that, when used in OFDM/OQAM systems, the proposed methods can provide better performance than the direct application of the existing controlled clipping tone reservation method, and even outperform the multi-block tone reservation method.

• Journal of The Korean Astronomical Society
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• v.52 no.4
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• pp.121-131
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• 2019

I investigate the origin of arc degeneracies in satellite microlens parallax ${\pi}_E$ measurements with only late time data, e.g., t > $t_0+t_E$ as seen from the satellite. I show that these are due to partial overlap of a series of osculating, exactly circular, degeneracies in the ${\pi}_E$ plane, each from a single measurement. In events with somewhat earlier data, these long arcs break up into two arclets, or (with even earlier data) two points, because these earlier measurements give rise to intersecting rather than osculating circles. The two arclets (or points) then constitute one pair of degeneracies in the well-known four-fold degeneracy of space-based microlens parallax. Using this framework of intersecting circles, I show that next-generation microlens satellite experiments could yield good ${\pi}_E$ determinations with only about five measurements per event, i.e., about 30 observations per day to monitor 1500 events per year. This could plausibly be done with a small (hence cheap, in the spirit of Gould & Yee 2012) satellite telescope, e.g., 20 cm.

• 한국벤처창업학회:학술대회논문집
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• 2022.04a
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• pp.157-161
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• 2022

Building on the DC interaction model between a parent company and its spin-offs, we examine that a dyadic relationship can be differentiated within the functions of space, motivation, and time. We investigate that these three factors encompassing the parent-spin-off DC relationship can be applicable to both linear(i.e., geographic proximity and low spin-off CEO's salary is positive) and nonlinear(i.e., too much frequency of new spin-off creation is as harmful as too little) effects on determining the performance of spin-off firms. The direction of causality is underpinned by social capital, human capital, and compensation-activation theory rather than by the normal consequences of previous empirical research. Further, our results suggest the overlap between DC and entrepreneurship; namely, spin-off firms create, learn, and exploit opportunities through a reconfiguration of parent DC so that DC establishes itself as a key concept in the entrepreneurship domain.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06c
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• pp.129-132
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• 1994

본 논문에서는 윈도우즈용 음성인식 software "voice access"를 개발하여 연구한 실시간 음성검출 알고리즘에 관해 소개한다. 이 음성검출 알고리즘은 200 sample 단위의 프레임 에너지, 프레임 영교차율, 음성의 길이를 음성검출의 파라메타로 사용한다. 각 파라메타의 문턱값은 신호의 평균값, 잡음의 표준편차, 미디안 표준편차와 한국어의 음성적 특성을 고려하여 설정하였으며 주변의 환경에 적응해 가며 문턱값을 조정하므로 주변 잡음환경의 변화에 대해서도 강인한 음성검출 결과를 보여준다. 또한 실시간으로 음성을 검출하므로 실용성이 높다. 음성의 검출은 일반사운드 카드를 통해 16-bit의 8KHz로 샘플링된 신호를 사용한다. 음성검출을 위한 분석은 200 sample 씩 하고 100 sample 씩 overlap 하면서 수행한다. 음성검출을 위한 모든 분석은 특별한 DSP의 도움없이 486D 이상에서 실시간으로 구현했다.시간으로 구현했다.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1102-1106
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• 2003

In our previous work we developed the Finite Field method in order to calculate the fifth-order Raman response. The method was applied to calculate various polarization components of the two-dimensional response of liquid $CS_2$. So far, all calculations relied on the dipole-induced dipole. Accurate time-dependent density functional theory calculations have shown that this model has big discrepancies, when molecules are close together as in the liquid. We now report results of investigations on the importance of multipole and electron overlap effects on the polarizability and the fifth-order Raman response. It is shown that these collision effects, especially the induced multipoles, are crucial in the description of the fifth-order response. The impact is found to be especially pronounced for the χ_{mmzzzz}^{(5)}$response that is solely due to interaction induced effects. The calculated response will be compared with various experimental results.

• IEIE Transactions on Smart Processing and Computing
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• v.5 no.4
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• pp.235-242
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• 2016

The emerging High-Efficiency Video Coding (HEVC) standard attempts to improve coding efficiency by a factor of two over H.264/Advanced Video Coding (AVC) at the expense of an increase in computational complexity. Mode decision with motion estimation (ME) is still one of the most time-consuming computations in HEVC, as it is with H.264/AVC. Thus, fast mode decisions are not only an important issue to be researched, but also an urgent one. Several schemes for fast mode decisions have been presented in reference software and in other studies. However, the conventional hierarchical mode decision can be useless when block-level parallelism is exploited. This paper proposes operation-level exploration that offers more chances for early termination. An early termination condition is checked between integer and fractional MEs and between the parts of one partition type. The fast decision points of the proposed algorithm do not overlap those in previous works. Thus, the proposed algorithms are easily used with other fast algorithms, and consequently, independent speed-up is possible.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.8 no.4
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• pp.260-263
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• 2008

In this paper we propose Personal Information Management System for Library Database. It manages personal search pattern for the given user and provide specific book list for library book search system. With the proposed system, the conventional overlap searching time will be decreased with personalized information and search history. This system manages the individual data according to personal searching pattern, sequence and usability. Therefore, the user can locate necessary book information more accurately with their distinct interest and search history.

• Bulletin of the Korean Chemical Society
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• v.17 no.7
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• pp.616-621
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• 1996

The transfer of excitation energy from solvent to solute in polystyrene films doped with 2-(2'-hydroxyphenyl)benzothiazole (HBT) which undergoes intramolecular proton transfer in excited electronic state has been studied by employing steady state and time-resolved fluorescence measurements. The degree of Forster overlap between donor and acceptor molecule in this system is estimated to be moderate. Energy transfer efficiency increases with solute concentration at low concentration range and levels off at high concentration. It is observed that the excimer form of polystyrene is largely involved in energy transfer process. Photostability of HBT in polystyrene to UV light is also investigated to get insight into the long wavelength absorption band of HBT which was observed upon electron radiation.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.4
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• pp.687-692
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• 2023

This research began with the intention to create music using the superposition characteristics of quantum computers. Existing music has characteristics that are limited to those composed by composers. However, music using the overlap of quantum computers has musical characteristics that change when executed within a limited range. Using this, you will be able to create music that changes based on specific chords at run time. In this paper, quantum computers and existing computers are connected to generate sound, And it focuses on creating changing sounds by applying the nature of superposition.