• 대한원격탐사학회지
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• 제38권4호
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• pp.343-353
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• 2022

An attempt to derive the surface temperature from the Korea Multi-purpose Satellite (KOMPSAT)-3A mid-wave infrared (MWIR) data acquired over the southern California on Nov. 14, 2015 has been made using the MODerate resolution atmospheric TRANsmission (MODTRAN) radiative transfer model. Since after the successful launch on March 25, 2015, the KOMPSAT-3A spacecraft and its two payload instruments - the high-resolution multispectral optical sensor and the scanner infrared imaging system (SIIS) - continue to operate properly. SIIS uses the MWIR spectral band of 3.3-5.2 ㎛ for data acquisition. As input data for the realistic simulation of the KOMPSAT-3A SIIS imaging conditions in the MODTRAN model, we used the National Centers for Environmental Prediction (NCEP) atmospheric profiles, the KOMPSAT-3Asensor response function, the solar and line-of-sight geometry, and the University of Wisconsin emissivity database. The land cover type of the study area includes water,sand, and agricultural (vegetated) land located in the southern California. Results of surface temperature showed the reasonable geographical pattern over water, sand, and agricultural land. It is however worthwhile to note that the surface temperature pattern does not resemble the top-of-atmosphere (TOA) radiance counterpart. This is because MWIR TOA radiances consist of both shortwave (0.2-5 ㎛) and longwave (5-50 ㎛) components and the surface temperature depends solely upon the surface emitted radiance of longwave components. We found in our case that the shortwave surface reflection primarily causes the difference of geographical pattern between surface temperature and TOA radiance. Validation of the surface temperature for this study is practically difficult to perform due to the lack of ground truth data. We therefore made simple comparisons with two datasets over Salton Sea: National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory (JPL) field data and Salton Sea data. The current estimate differs with these datasets by 2.2 K and 1.4 K, respectively, though it seems not possible to quantify factors causing such differences.

• 한국전자파학회논문지
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• 제15권9호
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• pp.896-905
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• 2004

본 논문에서는 이동통신 기지국 안테나로 활용하기 위한 구형 빔 패턴을 갖는 평면 배열 안테나 설계 및 제작 그리고 실험에 대하여 기술하였다. 원하는 구형 빔 패턴을 형성하기 위해 종래에 많이 사용하던 sin(x)/x 전류 분포를 사용하지 않고 급전 회로망의 설계 제작이 용이한 진폭과 위상 성분의 전류 분포로 최적화하였다. 본 논문에서 설계하는 평면 배열 안테나는 직사각형 격자 배열 구조를 가지며, 16${\times}$8 배열 소자로 구성된다. 각 방사 소자는 선형 수직 편파와 동축 여기 구조를 갖는 단일 마이크로스트립 소자이며, 월킨슨 전력 분배기와 180$^{\circ}$ 링 하이브리드 결합기를 기본 소자로 하는 급전 회로망이 설계된다. 평면 배열 안테나는 방위각 방향으로 는 0.55 λ$_{ο}$의 소자 간격을 갖는 16 배열 소자에 의해 90$^{\circ}$ 구형 빔 패턴을 형성하고, 양각 방향으로는 0.65 λ$_{ο}$의 소자 간격을 갖는 8 배열 소자에 의해 $10^{\circ}$의 일반적인 정형 빔 패턴을 형성한다. 또한, 16${\times}$8 배열 안테나는 좌우 상하 대칭적으로 네 부분으로 나뉘어져 있으며, 128개의 방사 소자, 32개의 1-4 행 분배기, 4개의 1-8 열 분배기 그리고 1개의 1-4 입력 전력 분배기로 구성된다. 본 논문에서 제안한 평면 배열 안테나 구조의 전기적인 특성을 검증하기 위하여 1.92～2.17 GHz(IMT2000 대역)에서 동작하는 평면 배열 안테나 실험 시제품을 제작하였으며, 실험 측정 성능들은 시뮬레이션 성능들과 매우 유사함을 보여 주었다.

• 복식
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• 제19권
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• pp.105-125
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• 1992

The research, aiming an automatic pattern design of Korean Costume by utilizing CAD system, tried Grading, Seaming and Marking with a theme of girl's color-strip blouse & skirt. The content & conclusion of the research can be outlined as follows; 1) As we reviewed the current situation of Korean costume which becomes more likely celebrational or festival costume, while the demand of it is getting increase, it's being dealt mostly as ready-made dresses with different qualities & designs. Especially childrens ready-made ones were highly demanded to be picked up as the theme. 2) For the original drawing of children's color-strip blouse & skirt, Kyung-Ja Park's drawing method was used here, and for the substitute of particular body parts absolute size, Joo-Won Lee's standard size chart from a size-study by ages. 3) To work with CAD system we had input master pattern, drawn for age 5 as basic size, then graded six step-sizes for 1-11 years old. For add-subtract of particular body parts size, we graded through computing the standard variation among items to get the pattern developed into ready-made standard size, we can make precise plotting by grading wanted size very rapidly if we correct the rule of changed items different from standard size to make utilization possible enough with easy order method of ready-made Korean Dress. 4) We produced Marker after attaching a margin to seam accordingly by parts for each pattern using P/D/S to mark, In mass gament-cutting, the loss of time and material can minimized. In this research the apparel CAD system which has been utilized and only be western fashion industry was introduced for the design of ready-made Korean costume and utilized it in Grading, Marking which are critical steps to improve productivity and have reported the result in the research. Thus we expect that less cost, improved productivity and better quality with minimized loss of material from marking as well as from prompt and precise size-drawing. Furthermore the utilization of CAD system is considered as an effective one in terms of the research & the development to remove effective one in terms of the research & the development to remove irrational elements in the design and production process of Korean costume as well as in terms of the study of Korean Costume development through creative works of Korean Costume.

• 한국해양공학회지
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• 제33권6호
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• pp.564-572
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• 2019

Numerical simulation of the sediment by the Delft3d model was conducted to examine the changes in the sediment budget transport caused by long-term wave changes at the Maengbang beach. Representative waves were generated with input reduction tools using NOAA NCEP wave data for about 40 years, i.e., from January 1979 to May 2019. To determine the adequacy of the model, wave and depth changes were compared and verified using wave and depth data observed for about 23 months beginning in March 2017. As a result of the error analysis, the bias was 0.05 and the root mean square error was 0.23, which indicated that the numerical wave results were satisfactory. Also, the observed change in depth and numerical result were similar. In addition, to examine the effect due to long-term changes in the waves, the NOAA wave data classified into each of the representative wave grades, and then the annual trend of the representative wave was analyzed. After deciding the weight of each wave class considering the changed wave environment in 2100, the amounts of sedimentation, deposition, and the sediment transport budget were reviewed for the same period. The results indicated that the sedimentation pattern did not change significantly compared to the current state, and the amount of the local sediment budget shown in the present state was slightly less. And there has been a local increase in the number of sediment budget transport, but there is no significant difference in the net and amount of sediment movements.

• 한국광학회지
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• 제19권1호
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• pp.9-14
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• 2008

본 논문에서는 테라헤르츠 대역에서 동작하는 새로운 구조의 Yagi-Uda 안테나를 설계하였다. 제안한 Yagi-Uda 안테나는 안테나의 driver를 반 파장 다이폴이 아닌 전 파장 다이폴을 사용함으로써 공진주파수에서 $2000{\Omega}$ 정도의 높은 입력 저항을 얻을 수 있었다. 바이어스 선에 Photonic Bandgap 구조를 적용하여 바이어스 선로로의 전류누설을 최소화 하였고, 안테나를 얇은 기판에 설계함으로써 기판의 비유전율로 인한 안테나의 임피던스 저하를 막고 Yagi-Uda 안테나 고유의 단방향 지향적인 복사특성을 나타나게 하였다. 따라서 제안한 Yagi-Uda 안테나는 포토믹서와의 임피던스 부정합 문제를 개선하여 테라헤르츠파의 출력을 증가 시킬 수 있을 것이라 예상한다.

• 한국정보통신학회논문지
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• 제7권8호
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• pp.1743-1750
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• 2003

근래에는 정확성과 신뢰성이 강한 센서리스 속도추정방법으로 전동기를 구동하기 위한 노력이 전개되고 있으며, 본 논문은 외란에 대한 강인성이 뛰어난 신경회로망을 이용하여 직류전동기의 센서리스 속도제어를 실현한 연구 결과이다. 〔6­8〕 신경회로망은 사람의 뇌가 경험을 통해 학습하듯이 주어진 입력에 대해 학습을 통하여 최적의 출력을 발생한다. 학습은 직류전동기의 수식모델을 통해 얻어진 전압$.$전류 및 회전자 속도를 입$.$출력 데이터로 사용하여 역전파 학습 알고리즘〔8〕을 통해 행하여지며, 학습 완료 후 얻은 최적의 연결강도를 이용하여 속도를 추정한다. 신경회로망에 의한 방식은 복잡한 알고리즘을 사용하지 않고도 정확한 속도 추정이 가능하며, 직류전동기의 문제점인 회전자 권선의 열에 의한 전동기의 성능 악화 및 속도 제어의 어려움을 해소하여 운전 조건에 따른 외란 등에도 강인한 제어 특성을 가질 뿐만 아니라 전 속도 영역에서 속도 응답 특성이 우수한 결과를 얻을 수 있었다.

• 조명전기설비학회논문지
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• 제13권2호
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• pp.80-87
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• 1999

본 논문은 신경회로망을 이용하여 배전선로상의 고저항 사고검출기법을 제안하였다. 다양한 토양에서 실시한 고저항 사고 데이터를 통해 $\upsilon-i$ 특성곡선을 얻고, 이 특성곡선으로 EMTP를 이용하여 고저항 사고를 모의하였다. 배전선로 고저항 사고검출을 위해 훈련 모델은 강자갈을 사용하였고, 토양의 조건을 달리하여 신경회로망의 사고검출 성능을 평가하였다. 신경회로망의 입력으로 사고 전류를 주파수 분석한 후, 이를 한 주기 평균하여 얻어진 짝.홀수 고조파, 기본파, 실효치 지수을 이용하였다. 신겨회로망의 검출성능을 테스트한 결과 제안된 방법이 뛰어남을 확인하였다.

• 대한기계학회논문집A
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• 제22권3호
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• pp.663-670
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• 1998

Most of feedback shift controllers developed in the past have fixed control parameters tuned by experts using a trial and error method. Therefore, those controllers cannot satisfy the best control performance under various driving conditions. To improve the shift quality under various driving conditions, a new self-organizing controller(SOC) that has an optimal control performance through self-learning of driving conditions and driver's pattern is designed in this study. The proposed SOC algorithm for the shift controller uses simple descent method and has less calculation time than complex fuzzy relation, thus makes real-time control passible. PCSV (Pressure Control Solenoid Valve) control current is used as a control input, and turbine speed of the torque converter is used indirectly to monitor the transient torque as a feedback signal, which is more convenient to use and economic than the torque signal measured directoly by a torque sensor. The results of computer simulations show that an apparent reduction of shift-transient torque is obtained through the process of each run without initial fuzzy rules and a good control performance in the shift-transient torque is also obtained.

• 한국인쇄학회지
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• 제29권2호
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• pp.1-13
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• 2011

The recent spotlight on electronic touch-screen display, a rapid breakthrough in the information society is evolving. Touch panel input device such as a keyboard or mouse without the use of, the on-screen character or a specific location or object on the person's hand touches a particular feature to identify the location of a panel is to be handled. The touch screen on the touch panel is used in the Ag paste is used mostly for low-curable paste. The thermal-curing paste according to the drying process of thermal energy consumption and improve the working environment of organic solvents have problems. In this study, Ag paste used in the non-thermal curing friendly and cost-effective UV curable paste was prepared. Current commercially available thermal-curable binder, was used instead of the flow characteristics of UV-curable oligomers and monomers with functional groups to give a single conductive Ag paste with the addition of a pattern could be formed. Ag paste as a result, thermal-curing adhesive, hardness, resistance and excellent reproduction of fine patterns and was available with screen printing environmentally friendly could see its potential as a patterning technology.

• 로봇학회논문지
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• 제8권3호
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• pp.143-149
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• 2013

This paper presents a new miniature haptic display to convey ample haptic information to a user of a handheld interface. There are buttons on interfaces or general electronic devices, but existing buttons provide haptic feedback of only one passive pattern to a user. Because humans perceive tactile and kinesthetic information simultaneously when they handle objects the proposed actuator provides both sensations at once. It is able to generate various levels of kinesthetic sensations when pressing a button under diverse situations. Also, vibrotactile feedback can be delivered for exciting haptic effects with numerous patterns. Its performance was evaluated in accordance with the resistive force by changing the intensity of the input current. Experiments show that the proposed actuator has the ability to provide numerous haptic sensations for more realistic and complex haptic experiences.