• 한국통신학회논문지
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• 제28권4C호
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• pp.365-373
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• 2003

본 논문에서는 수정 유클리드 알고리즘을 기반으로 임의의 메시지 길이 k 뿐 아니라 임의의 블록 길이 n를 갖는 RS 부호를 복호할 수 잇는 적응형 RS 복호기를 설계한다. 설계된 복호기는 임의의 길이를 갖는 단축형 RS 부호의 복호 전에 영들을 추가하지 않아도 되므로 단축형 RS 부호에 특히 유리하다. 또한 이들 RS 부호의 오류정정 능력 t의 값을 매 부호어 블록마다 실시간으로 변화시킬수 있으므로 응답 채널이 유용한 경우 채널의 시변 잡음 레벨에 적응적으로 오류 정정 능력을 변화시킬 수 있다. 제시된 복호기 구조는 수정 유클리드 알고리즘에 기반한 4단계는 파이프라인 처리를 수행한다 : (1) 신드롬 계산 (2) MEA 블록 (3) 에러크기 계산 (4) 복호기 실패 검사. 각 단계는 가변 길이의 RS 복호에 적합한 구조를 갖도록 설계된다. 수정 유클리드 알고리즘(MEA) 블록의 새로운 구조를 제시하고, 에러의 크기 계산을 위한 다항식 평가를 위해 역순 출력을 갖는 다항식 평가 회로를 채용한다. MEA 블록은 연산 셀들의 멀티플렉싱 기법과 배속의 전용 클럭 기법(overclocking)을 적용하여 간단한 하드웨어로써 처리 속도를 유지하도록 하였다. 최대 오류정정 능력이 10인 GF($2^8$) 상의 적응형 RS 부호를 VHDL로 설계하고, FPGA에 성공적으로 합성하였다.

• 산업공학
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• 제3권2호
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• pp.39-51
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• 1990

One of the most important and powerful tools available for design and/or study of the operation of complex systems and processes is simulation. Since automated material handling systems like AS/RS are often quite complex, a network-based simulation model is developed to analyze an automobile part supplier's automated storage and retrieval system(AS/RS). The network simulation model is implemented in the SLAM Ⅱ on a VAX 8800 computer. Performance of the AS/RS was tested for 3 dispatching rules, 3 work load levels, 2 storage policies, 3 levels of stacker crane break-down, and 2 conveyor system layouts. Results indicate that the AS/RS performance is primarily affected by the dispatching rule and work load level.

• 한국통신학회논문지
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• 제36권10A호
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• pp.809-815
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• 2011

본 논문에서는 고속 RS(Reed-Solomon) 복호기의 KES(Key Equation Solver) 블록 구현에 ME(Modified Euclidean) 알고리즘을 효율적으로 설계할 수 있는 구조를 제안하고 구현하였다. 제안된 구조에서는 각 PE(Processing Element) 블록을 제어하기 위해 새로운 상대변수를 정의하고 다항식으로 표현함으로써, 입출력 신호가 간단해지고, 차수계산회로가 필요 없기 때문에 회로의 복잡도를 줄일 수 있다. 또한, PE 회로가 오류 정정 능력 t와 무관하기 때문에, t가 증가함에 따라 KES 블록의 하드웨어 복잡도가 선형적으로 증가하는 장점을 가진다. 제안된 구조와 기존의 구조를 비교하기 위해, RS(255,239,8) 복호기에 대한 KES 블록을 구현하고, 0.13um CMOS cell library를 이용하여 합성하였다. 실험 결과로부터, 제안된 구조를 이용하여 적은 gate count로 고속 RS 복호기 구현이 가능함을 알 수 있다.

• ETRI Journal
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• 제34권1호
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• pp.102-105
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• 2012

To serve the growing demand of the bidirectional information exchange, we propose a single relay selection (RS) scheme for physical-layer network coding (PNC) in a bidirectional cooperative network consisting of two sources and multiple relays. This RS scheme selects a single best relay by maximizing the bottleneck of the capacity region of both information flows in the bidirectional network. We show that the proposed RS rule minimizes the outage probability and that it can be used as a performance benchmark for any RS rules with PNC. We derive a closed-form exact expression of the outage probability for the proposed RS rule and show that it achieves full diversity gain. Finally, numerical results demonstrate the validity of our analysis.

• 한국멀티미디어학회논문지
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• 제20권3호
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• pp.511-519
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• 2017

This Paper introduces the design and communication method between PLC (Programmable Logic Controller) and Arduino based on MODBUS Protocol. MODBUS connection can be established in a new or existing system very easily, therefore we used this protocol in our proposed system. In the field of automatic devices, multi-function serial port such as RS232, RS422, RS485, and so on creates a great convenience to the developer. This proposed system used RS485 as a key mediator for data exchanging on a connected network. We also believe that it will reduce the development cost in various automated industry because this system can be reused or can be implemented any such PLC installed machines. RS485 is used as a communication interface between PLC (as a slave) and Arduino (as a master), through which a reliable network is created for safe and fast communication. Furthermore, RS485 allows multiple devices(up to 32) to communicate at half duplex on a single pair of wires and provides a long connectivity area (up to 1200 meters) as compare to other device, which makes it a user-friendly for various devices in the automated industry. Moreover, Arduino can play as a mediator by connecting third party device and setup a communication network with PLC.

• Journal of Korean Vacuum Science & Technology
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• 제3권2호
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• pp.101-106
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• 1999

The main consideration factor to design a magnetron of the sputtering system for TFT-LCD metallization is high sheet resistance (Rs) uniformity which is provided by the high target erosion and high current efficiency. The present study has developed a rectangular magnetron for TFT-LCD to bve considered full target erosion and high film uniformity. After an aluminum-2 at.% and alloy target was installed in a magnetron source and the film was deposited on the glass of 600${\times}$720 mm, the Rs uniformity of the deposited film was measured as functions of the magnet tilt and magnet scanning configuration. And the target erosion profile was observed with the target voltage. When sputtered at 4mtorr and 10kW, the magnet tilt for the high Rs uniformity of 8.38% was 7mm. The plasma voltage at the dwell home and end for full-face target erosion, when scanned the magnetron was 120% compared to the mean voltage of the other area.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.487-494
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• 1992

This experiment was conducted to study the effect of addition of Lucerne juice (LJ) obtained by mechanical extraction of freshly harvested crop on the nutritive value of rice straw silage. Rice straw (RS) was ensiled with intact, NaOH or $NH_3$ treated LJ at 3:7 ratio on fresh weight basis (LJ RS, LJ NaOH RS and LJ $NH_3$ RS, respectively). Each alkali was mixed with fresh juice at a level of 4% of rice straw dry matter just before ensiling. Rice straw ensiled with water was prepared as the control (W RS). In the digestion trial, goats were allocated in a $4{\times}4$ Latin-square design and fed the diet containing three parts of RS silage and one part of wheat bran (DM basis). For the goats receiving the control silage, urea was supplemented at feeding time so as to adjust the nitrogen intake except for goats on LJ $NH_3$ RS silage. Crude protein content of RS silage was increased from 5.2 to 9.1% (DM basis) by the addition of intact LJ and to about 24% by $NH_3$ treated LJ. The control W RS silage contained only trace amount of lactic acid and was dominated by acetic and butyric acid. The addition of intact LJ reduced butyric acid content and $NH_3-N/TN$ of the silage whereas the addition of alkalized LJ increased those values and shifted to a butyrate type fermentation. Nutrient digestibilities and nitrogen balance of goats were almost the same when they were fed W RS and LJ RS silage indicating the addition of intact LJ did not improve the nutritive value. The addition of alkalized LJ significantly increased the fiber digestibilities of RS silage and $NH_3$ treatment was more effective than NaOH treatment. Postprandial ruminal $NH_3-N$ and blood urea nitrogen (BUN) concentrations were decreased by feeding LJ NaOH RS silage suggesting ruminal protein synthesis was enhanced along with the increase of energy supply for supply for rumen microbes by the alkali treatment. The advantageous fiber digestibilities of LJ $NH_3$ RS silage compared with those of LJ NaOH RS silage might be attributable to a sufficient nitrogen supply for microbial fiber digestion in the rumen.

• 콘크리트학회논문집
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• 제28권5호
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• pp.571-579
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• 2016

타설 후 3시간 만에 교통개방이 가능하기 때문에 최근 교량상판 교면개량공사 재료로 RS-LMC가 많이 사용되고 있다. 고속도로 상의 보수공사는 차량의 통행제한이 어렵기 때문에 RS-LMC를 사용한 교량의 교면개량공사는 초기양생단계에서부터 진동에 노출되게 되고 차량진동에 의해 균열이 발생한다. 본 연구에서는 RS-LMC의 초기양생단계에서 진동에 의한 균열특성을 파악하고자 12개의 실험체를 제작하여 실험을 수행하였다. 주요 실험변수는 라텍스-시멘트비(L/C)와 진폭이며 실제 교량의 진동환경을 모사할 수 있는 포장진동시험장치(Pavement Shaking Table)를 이용하여 진동실험을 하였다. 실험결과, 라텍스-시멘트비(L/C)가 증가할수록 균열 개수와 균열의 총 길이가 감소하는 경향이 나타났으나 15% 이상에서는 수렴하였다. 또한 Walter, D, G와 설계기준들이 제시하고 있는 균열 발생 변형률보다 훨씬 작은 변형률에서 균열이 발생하였다.

• 한국통신학회논문지
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• 제23권6호
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• pp.1575-1582
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• 1998

본 논문에서는 연집에러에 대한 대처방안으로 효과적인 RS(Reed-Solomon) 부호를 이용한 FEC(forward error correcting) 기법에 대한 연구가 이루어졌다. RS 부호화기 및 복호화기의 ASIC 구현을 위한 회로를 수정된 유클리드 알고리듬을 사용하여 설계 및 제안하였다. 제안된 회로의 동작을 흉내내는 방법으로 C 프로그램을 작성하여, 여러 가지의 에러 및 삭제 오류가 발생한 통신 선로를 가장하여 동작을 확인하였다. 이를 바탕으로 RS 부호화기 및 복호화기의 단일칩 구현을 위한 회로를 VHDL을 사용하여 시스톨릭 어레이 형태를 사용한 파이프라인 구조로 VLSI 설계하고 로직 시뮬레이션을 통해 검증하였으며 최종적으로 회로 합성에 성공하였다.

• Asia pacific journal of information systems
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• 제29권4호
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• pp.856-874
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• 2019

The performance of recommender systems (RS) has been measured mainly in terms of accuracy. However, there are other aspects of performance that are difficult to understand in terms of accuracy, such as coverage, serendipity, and satisfaction with recommended results. Moreover, particularly with RSs that suggest multiple items at a time, such as YouTube, user satisfaction with recommended results may vary not only depending on their accuracy, but also on their configuration, content, and design displayed to the user. This is true when classifying an RS as a single RS with one recommended result and as a multiple RS with diverse results. No empirical analysis has been conducted on the influence of the content and distribution of recommendation items on user satisfaction. In this study, we propose a research model representing the content and distribution of recommended items and how they affect user satisfaction with the RS. We focus on RSs that recommend multiple items. We performed an empirical analysis involving 149 YouTube users. The results suggest that user satisfaction with recommended results is significantly affected according to the HHI (Herfindahl-Hirschman Index). In addition, satisfaction significantly increased when the recommended item on the top of the list was the same category in terms of content that users were currently watching. Particularly when the purpose of using RS is hedonic, not utilitarian, the results showed greater satisfaction when the number of views of the recommended items was evenly distributed. However, other characteristics of selected content, such as view count and playback time, had relatively less impact on satisfaction with recommended items. To the best of our knowledge, this study is the first to show that the category concentration of items impacts user satisfaction on websites recommending diverse items in different categories using a content-based filtering system, such as YouTube. In addition, our use of the HHI index, which has been extensively used in economics research, to show the distributional characteristics of recommended items, is also unique. The HHI for categories of recommended items was useful in explaining user satisfaction.