• Journal of the Korean Society of Radiology
• /
• v.14 no.4
• /
• pp.467-475
• /
• 2020

The purpose of this study is to assess doses to ¹⁸F-FDG, a radioactive drug, during PET examinations, to alleviate anxiety about radiation in patients and carers, to minimize the indiscriminate examination progress caused by medical institution personnel and space clearance problems, and health examination. The dose assessment was measured using a thermo-fluorescent dosimeter (TLD) and an electronic personal dosimeter (EPD) at the location of the cervical (hypothyroid), thorax (heart), and lower abdomen (breeding line) which are the three highest tissue areas of the radiation tissue weighting. In addition, spatial dose rates and radioactivity in urine were measured using GM counters and ion boxes. The results are as follows: First, the personal dosimeter TLD was measured 0.0425±0.0277 mSv in the cervical region, 0.0440±0.0386 mSv in the thorax and 0.0485±0.0436 mSv in the lower abdomen, with little difference in the heart dose depending on radiation sensitivity. The EPD was measured at 0.942±0.141 mSv/h immediately after the cervical position, and 0.192±0.031 mSv/h after 120 minutes. Immediately after the thorax position, 0.516±0.085 mSv/h, 120 minutes later 0.128±0.040 mSv/h. Immediately after the lower abdomen position, 0.468±0.091 mSv/h, and after 120 minutes 0.105±0.021 mSv/h were measured. The spatial dose rate at the GM counter was measured immediately at 0.041±0.005 mSv/h, 120 minutes later at 0.014±0.002 mSv/h. The radioactivity in urine using ion chamber was measured at 0.113±0.24 MBq/cc after 60 minutes and 0.063±0.13 MBq/cc after 120 minutes. As a result, ¹⁸F-FDG should be administered, dose re-evaluated two hours after the PET test is completed, and caregivers should be avoided. In addition, it is deemed necessary to provide patients and carers with sufficient explanations and expected values of exposure dose to avoid reckless testing. It is hoped that the data tested in this study will help patients and families relieve anxiety about radiation, and that the radiation workers' exposure management system and institutional improvements will contribute to the development of medical radiation.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.16 no.3
• /
• pp.147-156
• /
• 2016

A modalized Łukasiewicz three-valued propositional logic will be proposed in this paper which there are three modalities [t]; [m]; [f] to represent the three values t; m; f; respectively. And a Gentzen-typed deduction system will be given so that the the system is sound and complete with respect to the Łukasiewicz three-valued semantics Ł$_3$, which are given in soundness theorem and completeness theorem.

• Journal of IKEEE
• /
• v.13 no.2
• /
• pp.194-199
• /
• 2009

In this study, ultra high-voltage (170kV AC), reliable 80pF mica capacitors for partial discharge system application were investigated. For capacitors design, Program was developed to sampling of series and parallel parameters. Mica was used as the dielectric of the capacitors. Using the conservative design rule, over 3 individual 50$\mu$m thick mica sheets with a size of 30mm$\times$35mm were used with lead foils to form a parallel capacitor element and 20 mica sheets were interleaved with lead foils to form a series stack of parallel capacitor element to meet the requirements of the capacitors. The dimension of the fabricated 80pF capacitor for 17kV AC were 90mm$\times$90mm. The high-frequency characteristics of the capacitance (C) and dissipation factor (D) of the developed capacitors were measured using a capacitance meter. The developed capacitor exhibited C of 79.5pF, had D of 0.001% over the frequency ranges of 150kHz to 50MHz, had a self-resonant frequency of 65MHz.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.10a
• /
• pp.815-817
• /
• 2012

본 논문에서는 차량 충돌 예방 레이더 시스템-온-칩용 77GHz 고주파 전단부(RF front-end)를 제안한다. 이러한 고주파 전단부는 77GHz의 동작주파수를 가진 저 잡음 증폭기와 고주파 전력 증폭기로 구성된다. 이러한 회로는 TSMC $0.13{\mu}m$ 혼성신호/고주파 CMOS 공정 ($f_T/f_{MAX}=120/140GHz$)으로 설계되어 있다. 저잡음 증폭기의 경우 전압이득이 36dB로 최근 발표된 연구결과 중 가장 우수한 수치를 보였다. 전력 증폭기는 포화전력과 출력 $P_{1dB}$이 18dBm과 15dBm으로 기존 연구결과 중 가장 우수한 결과를 각각 보였다.

• The Bulletin of The Korean Astronomical Society
• /
• v.36 no.1
• /
• pp.68.1-68.1
• /
• 2011

이 연구에서는 한국과학영재학교 SEMO 천문대 리치크레티앙 16인치 반사망원경에 장착된 CCD를 연구용으로 사용하기 위해 기기적인 특성을 조사하였다. 한국과학영재학교 학생들은 천문대의 장비를 활용하여 2006년부터 개인연구 및 R&E 연구를 수행하고 있다. 최근 2010년 8월에 시야각을 넓히기 위하여 초점비를 f/9에서 f/5.4로 낮추는 리듀서를 장착하였고 CCD 특성을 파악하고자 한다. 이번 연구는 이 관측 시스템에서 얻을 수 있는 자료의 한계와 신뢰성을 검증하고자 하고 사용하고 있는 CCD 의 기기적 특성을 고려하고자 한다. 이 연구에서는 영점 영상, 암전자 영상, 바닥 고르기 영상을 얻었고, 포화 한계, 선형도, 노출시간에 따른 공간적 차이 등을 조사하였다. 최종적으로는 B, V 필터를 이용한 표준성 측광을 수행하여 시스템의 신뢰성을 검증해 보았다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2020.05a
• /
• pp.526-529
• /
• 2020

최근 네트워크 환경에 대한 공격이 급속도로 고도화 및 지능화 되고 있기에, 기존의 시그니처 기반 침입탐지 시스템은 한계점이 명확해지고 있다. 이러한 문제를 해결하기 위해서 기계학습 기반의 침입 탐지 시스템에 대한 연구가 활발히 진행되고 있지만 기계학습을 침입 탐지에 이용하기 위해서는 두 가지 문제에 직면한다. 첫 번째는 실시간 탐지를 위한 학습과 연관된 중요 특징들을 선별하는 문제이며 두 번째는 학습에 사용되는 데이터의 불균형 문제로, 기계학습 알고리즘들은 데이터에 의존적이기에 이러한 문제는 치명적이다. 본 논문에서는 위 제시된 문제들을 해결하기 위해서 Hybrid Feature Selection과 Data Balancing을 통한 심층 신경망 기반의 네트워크 침입 탐지 모델을 제안한다. NSL-KDD 데이터 셋을 통해 학습을 진행하였으며, 평가를 위해 Accuracy, Precision, Recall, F1 Score 지표를 사용하였다. 본 논문에서 제안된 모델은 Random Forest 및 기본 심층 신경망 모델과 비교해 F1 Score를 기준으로 7~9%의 성능 향상을 이루었다.

• 제어로봇시스템학회:학술대회논문집
• /
• 1989.10a
• /
• pp.188-193
• /
• 1989

This paper is proposed of multirate nonlinear controller for robot manipulator. The proposed controller is obtained by structure changes of feedback controller with C.T.M and for time differences commanded in caculating each term of controller, multirate sampling is used. And more robust controller is proposed by considering one-step ahead predictive action. In order to evaluate proposed controller, computer simulation is performed for a 3 D.O.F robot manipulator with varying load.

• The Optical Journal
• /
• s.125
• /
• pp.41-43
• /
• 2010

(주)위오(대표 서동수, www.weeo.co.kr)는 1998년 비디오 도어폰용 카메라 렌즈 제조 전문업체인 M.F. 전광(주)의 자회사로 2003년 1 월 9일 납입자본금 5천만원과 첨단 지능형 자동차 안전시스템용 카메라 렌즈 개발 및 해외 판매 법인으로 출발했다. 2명으로 출발한 직원이 현재 30여명에 이르며 매출 30억원의 내실있는 중소기업으로 발돋움한 이 회사는 2010년 경인년(庚寅年)을 제2 도약의 원년으로 설정하고 2015년까지 첨단 자동차 부품 선도업체로의 도약을 준비하고 있다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 1993.06a
• /
• pp.1171-1174
• /
• 1993

A promising approach to get the benefits of neural networks and fuzzy logic is to combine them into an integrated system to merge the computational power of neural networks and the representation and reasoning properties of fuzzy logic. In this context, this paper presents a fuzzy neural network which is able to code fuzzy knowledge in the form of it-then rules in its structure. The network also provides an efficient structure not only to code knowledge, but also to support fuzzy reasoning and information processing. A learning scheme is also derived for a class of membership functions.

• Proceedings of the IEEK Conference
• /
• 2009.05a
• /
• pp.182-184
• /
• 2009

FlexRay is a new standard of network communication system which provides a high speed serial communication, time triggered bus and fault tolerant communication between electronic devices for future automotive and ship applications. FlexRay communication controller(CC) is the core of the FlexRay protocol specification. In this paper, we first design the FlexRay CC protocol specification and function parts using SDL(Specification and Description Language). Then, the system is re-designed using Verilog HDL based on the SDL source. The FlexRay CC system was synthesized using Samsung $0.35{\mu}m$ technology. It is shown that the designed system can operate in the frequency range above 80 MHz. In addition, to show the validity of the designed FlexRay system, the FlexRay system is combined with sound source localization system in Robot applications. The combined system is implemented using ALTERA Excalibur ARM EPXA4F672C3. It is shown that the implemented system operates successfully.