• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.7
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• pp.1-6
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• 2009

This paper presents new high speed architecture using DBI(Data Bus Inversion) in DRAM. The DBI is one of the general methods in the signaling circuits to decrease the known problems such as SSO and LSI. Many architectures have been proposed to reduce the number of transitions on the data bus. In this paper, the DBI, the Analog Majority Voter (AMV) circuit, the GIO control circuit and the SSO algorithm are newly proposed. The power consumption can he reduced with the help of direct GIO inversion method and the eye diagram of data can be increased to 40ps. Using proposed DBI scheme can produce almost stable SI of DQs against high speed operation. The DBI is fabricated in 90nm CMOS Technology.

• Journal of the Korean Society of Safety
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• v.33 no.1
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• pp.1-6
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• 2018

The effects of the fiber direction, specimen size and temperature on the compressive strength of carbon fiber reinforced silicon carbide composite (C/SiC composite) manufactured by liquid silicon infiltration(LSI) is investigated. Tests were conducted in accordance with ASTM C 695 at room temperature and elevated temperatures. Experiments are conducted with two different specimens considering grain direction. With grain (W/G) specimens have a carbon fibers parallel to the load direction, but across grain (A/G) specimens have a perpendicular carbon fibers. To verify the specimen size effect of C/SiC composite, two types of specimens are manufactured. One has a one to two ratio of diameter to height and the other has a one to one ratio. The compressive strength of C/SiC composite increased as temperature rise. As specimens are larger, compressive strength of A/G specimens increased, however compressive strength of W/G decreased.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.5
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• pp.1004-1010
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• 1992

In recent years, along with the development of ultrasonic probe with wide frequency range, the digitization of measuring instrument, and the development of operating process technics, it is possible to analyze ultrasonic pulse in frequency range. In this paper, applying to flaw model the ultrasonic spectroscopy method that can analyze ultrassonic pulse in frequency range, we examine the possibility of quantification of flaw and apply its result to the void and seperation in LSI package. Consequently, by using the change in frequency distribution and central frequency of sltrasonic pulse detected from flaw, the estimation of shape, size, and depth of flaw is possible. The change in central frequency is changed minutely by the sample materals and position of flaw, but changed mainly by the shape and size of flaw. And we can quantify the shape and size of flaw in LSI pakcage using the experimental result through flaw model.

• Annual Conference on Human and Language Technology
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• 2009.10a
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• pp.165-169
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• 2009

오늘날 인터넷 검색은 하루가 다르게 발전되고 있다. 주로 키워드 매칭에 의존을 둔 지금의 검색 서비스들은 사용자 중심의 아이템들을 개발해 정보검색의 경과시간 및 결과의 분류면에서 우수함을 보여주고 있다. 질의어의 의미에 유사한 검색은 아직은 발전하는 단계로, 내용에 기반을 둔 검색 환경에 초점이 맞춰지고 있다. 이와 관련하여 행렬의 특이치 분해(SVD)를 이용한 잠재적 의미 색인 기법(LSI)을 본 연구에서 다루고자 한다. 구축한 시스템의 성능 평가는 재현도 계산으로 비교되었는데 작은 크기의 특이값(singular value)들 생략에 의한 SVD의 성능과 그것을 재이용, 질의어에 대한 의미 구조상 근접한 용어들을 찾아 질의어를 확장한 후 적합한 문서들의 검색을 사용한 특이값 개수, 유사단어 확장 개수를 달리하여 실험하였다. 실험 결과, 특이값 2개를 사용한 잠재적 의미 색인이 특이값 3개를 사용한 잠재적 의미 색인보다 보다 나은 성능을 보였다. 그리고 조건을 달리한 모든 잠재적 의미 색인의 경우 단어 매칭에 의한 적합문서 검색보다 별 뚜렷한 나은 결과는 보이지 않았다. 하지만 의미적으로 관계가 깊은 유사어들을 찾아냈고, 의미적으로 가장 관계 깊은 문서를 대부분의 경우에서 순위 1위로 찾아내는 부분적 우수함을 보였다.

• Electronics and Telecommunications Trends
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• v.3 no.2
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• pp.116-133
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• 1988

ASIC (Application Specific Integrated Circuit)은 직역하면 응용특정 IC, 혹은 특정용도 IC로서 LSI시장의 조사회사인 Dataquest사가 '84년경부터 사용하기 시작한 말이다. ASIC이 최근 크게 주목을 끌고있는 것은, 반도체 사용자가 자신의 제품에 개성을 불어넣기 위해서는 범용IC를 사용해온 것으로는 기술적 우위성이 확보되지 않는다고 판단했기 때문에 주문형 LSI를 강하게 추진해 왔다는 것과 반도체 메이커도 메모리IC를 중심으로 한 범용IC시장의 부진, 더우기 날로 더해가는 반도체 시장의 시장쟁탈 및 무역마찰로 인해 ASIC 시장에로의 참여가 강화되어 왔다는 점 등을 들수있다. 집적화 기술은 매년 진보하여 지금은 100만개 이상의 트랜지스터를 집적할 수 있게 되었다. 따라서 지금까지 SSI/MSI를 사용해서 회로설계한 기능단위의 칩을 프린터 기판위에 조합시켜 시스팀을 구축해 왔으나, 앞으로는 하나의 칩위에 시스팀을 구성하는 시대로 변하고 있다. ASIC은 그 요청에 따라서 one-chip화의 개념에 따라서 만들어진 것으로서, 시장환경에 대단히 유익한 디바이스로 생각할 수 있다. 시스팀의 one-chip화의 실현결과 압도적으로 소형화, 경량화, 성자원화가 달성됨과 동시에 신뢰성 및 동작성능도 우수하게 되었다. ASIC기술은 현재 주류로 되어있는 게이트 어레이를 볼때, 개발비용은 크게 감소하여 개발기간도 논리회로가 완성된다면 3~4주 정도로 단축시킬수 있다. ASIC 설계에는 각 공정에 있어서 고도의 컴퓨터 지원설계가 채용되고 제조공정에서는 첨단의 프로세서 기술 등이 이용되므로 ASIC기술은 종합적인 첨단기술의 집약이라고 불러도 좋을것이다. 이러한 기술추세에 맞추어 전자통신 동향분석지 제3권 제1호(1988.3.)에 발표된 최신 ASIC기술동향의 후속편으로 ASIC에 관련된 중요용어 50개를 선정, 알파벳 순으로 나열하여 설명하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.8
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• pp.1782-1789
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• 1997

Most systems that retrieve distributed information on the Internet have difficulties in retrieving relevant information for they are not able to reflect exact semantics on retrieval queries that usersrequest. In this paepr, we propose an automatic query expansion based on ter distribution which reflects semantics of retrieval term to emhance the performance of information retrieval. We computed weight, indicating its overal imoritance in the collection documents and user's query and we use LSI's SVD technique to measure the term distribution which appears similar to query. And also, we measure the similarity to compared numerical value with query terms. Also we researched the method to reduce additional terms automatically and evaluated the performance of the proposed method.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.3
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• pp.285-293
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• 1999

In this paper, the novel digital frequency/phase controller, to control the invelter fed traveling wave type ultra-sonic m motor(USM) is proposed. This controller is used to control the drive frequency, phase difference and applied voltages of e each phase of the motor. Proposed digital controller has constructed with digital logic only, no more use digitallongleftarrowanalog h hybrid method of the conventional controller, in order to generate drive frequency and phase difference. Therefore, the c control system has become to velY simple structure. T\rvo types of controllers are designed, one is to control drive f frequency and phase difference, another has added voltage control function of each phase. Two full digital voltage/phase c controllers are implemented by using custom LSI and EPLD, the control pelformance and the simplicity ofthe proposed c controller is verified by expeJimental results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.545-551
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• 2011

Recently, demands for generating high quality tap waters are increasing with high concern of water pollution and corrosion of water pipelines. For the reasons, developing water quality stabilization technique in water purification system is sought rather than replacing to a new pipelines. In this study, high-purity liquid lime($Ca(OH)_2$) was introduced for a water quality stabilization technique in water purification process and simulated water distribution system of pilot-scale size was applied to evaluate anti-corrosion control effect. The effect of anti-corrosion control was calculated in terms of LSI(Langelier Saturation Index) In conclusion, the result of pilot plant showed improvement of corrosiveness by liquid lime($Ca(OH)_2$) with reduction of released iron(Fe). Application of anti-corrosion control technique to the mild steel coupon and the copper coupon were effective by indicating 35.4, 44.5% of improvements. Besides, sample pipes which were treated with liquid lime had formated more thicker layer of corrosion product inside of pipes. As a result, the process of injecting water stabilizer can greatly contribute to the high quality of tap water.

• Communications of Mathematical Education
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• v.27 no.4
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• pp.473-486
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• 2013

This study examines the learning styles of freshmen enrolled in a college of science and engineering, and analyses the relationship between learning styles and academic achievement in mathematics to provide basic data for the teaching-learning methods, which are more suitable to learning styles of students. For the purpose of this research, a reliability analysis of Kolb's LSI is applied to 282 freshmen enrolled in a college of science and engineering of the medium-sized university. The outcomes of this survey are followings. Firstly, students hold higher positions in the order of converger, assimilator, accommodator, diverger among 4 learning styles. Secondly, while there is a positive corelation between abstract conceptualization[AC] and academic achievement, there is a negative corelation between concrete experience[CE] and academic achievement. Thirdly, as for academic achievement in mathematics, converger is superior to assimilator and accommodator. Finally, the correlation between learning styles and academic achievement is different by demographic characteristics. Based on these results, this study suggests the necessity for various teaching-learning strategies, which are adjusted to both academic characteristics of mathematics and learning styles. Also, the need for teaching methods, which help students to develop effectively four learning cycles, is proposed.

• Journal of Korean Electronics
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• v.3 no.6
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• pp.29-31
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• 1983

우리나라 반도체 산업의 수출은 82년의 6.3억불에서 90년에는 30억불로 확대되고 기초 소재 부분의 국산화가 현재 리드프례임 정도에 불과하나 90년에 가서는 수지 및 화공약품까지 자급화를 목표로 하고 있다. 86년까지는 컴퓨터 에이디드 디자인 활용으로 설계 능력을 보유토록 할 것이며 웨이퍼 가공 부분에서 현재 3인치 웨이퍼 가공을 4~5인치 가공으로 확대하고 가공 품목을 LSI급으로 높이며 자동화 착수 수단인 조립공정을 완전 자동화하도록 향상시킬 것이다.