• Proceedings of the KSME Conference
• /
• 2002.08a
• /
• pp.639-642
• /
• 2002

A tubular centrifugal fin is designed by using various methods of analysis and design. A preliminary design method based on empirical optimum curves for centrifugal fin is used to determine the geometric parameters for tubular centrifugal fan. And, Quasi-3D streamline curvature duct-flow analysis is used to provide the primary position of streamlines and spanwise distribution of flow angle f3r generation of blade geometry based on S1 surface. Three-dimensional CFD solution then is obtained to optimize the blade design. Constriction of flow path in the region of impeller, backward swept blade, and central cone, which are introduced to improve the design, successfully remove or suppress the vortices downstream of the impeller.

• Electronics and Telecommunications Trends
• /
• v.23 no.3
• /
• pp.19-28
• /
• 2008

2007년 3월부터 WFA에서 시작된 "Wi-Fi CERTIFIED(TM)802.11n Draft 2.0" 인증을 통해 현재까지 180가지가 넘는 제품이 출시되고 있는 가운데 이러한 시장의 상황을 반영하듯 여러 매체를 통해 IEEE 802.11n이 2008년 핫이슈로 등장하고 있다. 하지만 차세대무선통신의 기술적인 로드맵을 선도하고 있는 ITU-R WP8F의 IMT-Advanced에서 요구하고 있는 보행시 1Gbps까지 가능하게 하는 기술을 2010년까지 제공한다는 측면에서는 IEEE 802.11n의 성능이 못 미치는 게 사실이며, 이러한 상황을 반영해 IEEE 802.11 내부에서 IEEE 802.11n 후속으로 보행시 Gbps급의 전송 속도를 지원하는 새로운 기술에 대한 표준화 작업에 대한 논의가 꾸준히 있어 왔고, 그 결과 2007년 5월 정식으로 이를 위한 Study Group이 만들어져 작업에 들어갔다. 본 고에서는 이러한 IEEE 802.11에서의 표준화 활동을 중심으로 차세대무선랜에 대한 응용분야, 관련 기술, 표준화 작업 내용에 대해 살펴보고자 한다.

• Journal of Korea Multimedia Society
• /
• v.21 no.9
• /
• pp.1119-1130
• /
• 2018

Writing letters or patterns on a virtual space by moving a person's gaze is called "eye writing," which is a promising tool for various human-computer interface applications. This paper investigates the use of conventional eye writing recognition algorithms for the purpose of user-independent recognition of eye-written characters. Two algorithms are presented to build the user-independent system: eye-written region extraction using wavelet coefficients and template generation. The experimental results of the proposed system demonstrated that with dynamic positional warping, an F1 score of 79.61% was achieved for 12 eye-written patterns, thereby indicating the possibility of user-independent use of eye writing.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.14 no.2
• /
• pp.299-304
• /
• 2011

In this paper, we developed the semiconductor neutron radiation detector and the multi-purpose radiation detection technologies for the next generation military personal surveymeter. The PIN type semiconductor neutron detector and the prototype measure the neutron radiation dose upto 1,000cGy with ${\pm}20%$ error. It also have a good performance about the Gamma, Alpha and Beta radiation and MIL-STD-810F.

• Proceedings of the KACD Conference
• /
• 2001.11a
• /
• pp.585.2-585
• /
• 2001

The purpose of this study was to evaluate the microtensile bond strength of sixth-generation adhesives according to various dentin surface treatments and to observe the interface between resin(Z-100TM) and dentin by SEM. This study employed forty-five non-caries extracted human molars and three adhesive systems were used; All-Bond 2(AB), One-Up Bond F(OU), AQ-Bond(AQ).; group 1, 2, 3 were used AB and were respectively treated by smearing(S), ultrasonic cleansing(US), etching(E).(omitted)

• Journal of the Korean Ceramic Society
• /
• v.34 no.10
• /
• pp.1060-1066
• /
• 1997

In this paper, the effects of La addition of PLZT thin film prepared by sol-gel method on the capacitor characteristics are investigated for gigabit generation DRAM applications. The addition of La on the PLZT capacitor results in a trade-off between charge storage density(Qc') and leakage current density(Jl). As La content increases, Qc' and permeability(εr) at 0V are reduced while Jl is significantly decreased. It is demonstrated that 5% La doping of PZT can substantially reduce Jl and also improve resistance to fatigue while incurring only minimal degradation of Qc'. Very low leakage current density (5×10-7 A/㎠ even at 125℃) and high charge storage density (100fC/㎛2) under VDD/2=1V conditions are achieved using 5% La doped PZT thin films for gigabit DRAM capacitor dielectrics. In addition, the fatigue and TDDB measurements indicate good reliability of the PLZT capacitors.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.22 no.6
• /
• pp.13-18
• /
• 1985

A set of utility programs for automatic generation, minimization and verification of high density PLA layout was developed, which includes equation-to-truth table translator, logic minimizer, PLA product term sorter, file generator for plotting stick diagram, dynamic CMOS PLA layout generator and bipartite row folded CMOS PLA layout generator. Size reduction is performed mainly by logic minimizer and bipartite row folder, and the maximal delay is reduced by sorter. The fOe for automatically generated layout is stored in CIF. Each program was written in Clanguage, and was run on VAX-11/750 (UNIX).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.11a
• /
• pp.283-286
• /
• 2000

In this paper, generation form of displacement current was compared and measured induce monolayers which 8A5H with Pure azobenzene. Light response of two monolayers which compared and measured though they are the same isomer. The experimental results are as following; In case of ultraviolet($\lambda_1$) and visible($\lambda_2$) irradiation on 8A5H induce monolayers depositioned on board the peak of current was detected about 10[fA]. but light irradiation on pure azobenzene any particular reaction for detailed. This is the reason of hydrophobicity construct in molecule structures its molecule dynamic behaviour in cis and trans was not due to activated.

• Nuclear Engineering and Technology
• /
• v.53 no.7
• /
• pp.2126-2132
• /
• 2021

Various research groups and private interprises are pursuing the design of a Molten Salt Reactor (MSR) as one of the Generation-IV concepts. In the current work a fast neutron MSR using chloride fuel is analyzed, specially analyzing the power production and neutron flux level in the Intermediate Heat Exchanger (IHX). The neutronic analysis in this work is based on a chloride-fuel MSR with 600 MW thermal power. The core power density was set to 100 MW m-3 with a core H/D [[EQUATION]] 1.0 amd four Intermediate Heat Exchanger (IHX). This leads to a power of 150 MW per IHX; this power is also comparable to the IHX proposed in the SAMOFAR framework. In this work, a preliminary design of a 150 MW helical-coil IHX for a chloride-fueled MSR is prepared and the fission rate, capture rate, and inelastic scatter rate are evaluated.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2022.11a
• /
• pp.390-392
• /
• 2022

기계학습 분야에서 모델을 학습시키려면 많은 양의 데이터가 필요하다. 최근에는 컴퓨터 비전 분야에서 데이터가 적은 환경에서 모델을 학습하는 다양한 방법들이 소개되고 있다. 하지만 대부분의 방법을 사용하기 위해서는 어느 정도 최소한의 학습 데이터가 필요하기 때문에 극심하게 데이터가 부족한 환경에서는 사용하기 어렵다. 본 논문에서는 컴퓨터 비전 분야에서 기계학습을 사용할 때 극심하게 데이터가 부족한 환경에서 시뮬레이션 도구를 활용한 인조 데이터 생성 방법을 제안한다. 실험 결과를 통해 시뮬레이션 도구를 활용하여 생성한 인조 데이터로 학습한 모델이 실제 데이터만을 학습한 모델을 대체할 수 있음을 확인하였고, F-1 점수와 정확도가 향상함을 실험적으로 확인하였다.