• 제목/요약/키워드: Park Yul

검색결과 1,173건 처리시간 0.027초

철도 통신신호에서의 LDPC에 적용에 관한 연구 (The Study of LDPC for Railroad Signal control system)

  • 박주열;김효상;박태기;김봉택;정기석
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.442-446
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    • 2009
  • As the railway transportation is getting faster and its operation speed has increased rapidly, its signal control has been complicated. For real time signal processing it is very important to prohibit any critical error from causing the system to malfunction. Today, most of the railroad's controling communications between wayside and train are made in one way. Therefore, by using a forward error correction technique, which receiver can actively correct the signal error, we can increase the performance and the stability of the railroad signaling system. In this paper, we introduce low density parity check(LDPC) that is used by next generation wireless communications and DMB technique. We verified that we can achieve low bit error rate(BER) in high signal to noise ratio(SNR) by using LDPC.

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System Dynamics 모델을 이용한 국내 3PL 시장의 효율적인 육성 방안에 관한 연구 (A Study on Efficient Supporting Policy of Domestic 3PL Market Using System Dynamics Model)

  • 이재원;김남균;박영재;박찬익;이재율
    • 한국시스템다이내믹스연구
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    • 제9권1호
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    • pp.107-123
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    • 2008
  • Recently, due to the globalization of business, the efficient supply chain management(SCM) is considered as the key initiatives of business activities, and the leading logistics companies are trying to provide the differentiated 3PL services to meet their customers' needs. The domestic 3PL market scale, however, is still small and the logistics companies' competence is not good enough, so that 3PL companies need to concentrate on their logistics strategies and the government's supports and related policies are required. In this point of view, we developed the system dynamics model and forecasted middle or long-term domestic 3PL market. Through the result, we suggest the roles of government and the directions of policies to support the domestic 3PL market effectively.

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키팩트 색인텀에 기반한 정보검색 시스템 (An Information Retrieval System Based on Keyfact Index Term)

  • 박의규;나동열;변성찬;정경택;박세영
    • 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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    • 한국정보과학회언어공학연구회 2000년도 제12회 한글 및 한국어 정보처리 학술대회
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    • pp.245-251
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    • 2000
  • 지금까지의 정보검색 시스템은 소위 키워드 기반 정보검색 시스템으로서 색인이 단일 단어(single word) 즉 키워드의 집합으로 나타내어 진다. 그러나 이 방법은 문서의 내용을 정확히 표현하는 데 한계가 있다. 따라서 최근에는 단어 이상의 구문 단위인 구(phrase)를 이용하여 색인과 검색을 하도록 하는 시스템을 개발하고자 하는 추세에 있다. 따라서, 본 논문에서는 키워드보다는 의미를 좀더 잘 나타내고 일반적인 구보다는 정형화된 형태의 색인 단위인 키팩트를 색인어로 하는 정보검색시스템을 개발하고 이의 성능을 살펴보았다.

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The Change of the Components and Forms of the Counterfeit l00mg VIAGRA$^{TM}$ Tablets

  • Baeck, Seung-Kyung;Yang, Hoo-Yul;Lim, Mie-Ae;Park, Yoo-Sin;Kim, Sun-Chun;Kim, Dong-Woo;Park, She-Youn;Lee, Ju-Seon
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.106.3-107
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    • 2003
  • VIAGRATM, an oral therapeutic agent for erectile dysfunction, is the citrate salt of sildenafil. VIAGRATM is formulated as blue, film-coated rounded-dia-mond-shaped tablets, equivalent to 25mg, 50mg and 100mg of sildenafil for oral administration. ViagraTM has been allowed to be sold at the drug store in Korea officially, but it is still increased to sell or use counterfeits or smuggled goods, because of its high price or strict restriction on both sale and purchase. Discrimination and analysis of 13 cases of VIAGRATM tablets for verification of genuineness or counterfeit were requested to our institute on the period, from January 1999 to July 2003. (omitted)

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$3{\mu}m$ 설계 칫수의 이중금속 CMOS 기술을 이용한 표준셀 라이브러리 (A $3{\mu}m$ Standard Cell Library Implemented in Single Poly Double Metal CMOS Technology)

  • 박종훈;박춘성;김봉열;이문기
    • 대한전자공학회논문지
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    • 제24권2호
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    • pp.254-259
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    • 1987
  • This paper describes the CMOS standard cell library implemented in double metal single poly gate process with 3\ulcornerm design rule, and its results of testing. This standard cell library contains total 33 cells of random logic gates, flip-flop gates and input/output buffers. All of cell was made to have the equal height of 98\ulcornerm, and width in multiple constant grid of 9 \ulcornerm. For cell data base, the electric characteristics of each cell is investigated and delay is characterized in terms of fanout. As the testing results of Ring Oscillator among the cell library, the average delay time for Inverter is 1.05 (ns), and the delay time due to channel routing metal is 0.65(ps)per unit length.

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일함수 변화를 통한 그래핀 전극의 배리어 튜닝하기 (Study of the Carrier Injection Barrier by Tuning Graphene Electrode Work Function for Organic Light Emitting Diodes OLED)

  • 김지훈;맹민재;홍종암;황주현;최홍규;문제현;이정익;정대율;최성율;박용섭
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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    • pp.111.2-111.2
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    • 2015
  • Typical electrodes (metal or indium tin oxide (ITO)), which were used in conventional organic light emitting devices (OLEDs) structure, have transparency and conductivity, but, it is not suitable as the electrode of the flexible OLEDs (f-OLEDs) due to its brittle property. Although Graphene is the most well-known alternative material for conventional electrode because of present electrode properties as well as flexibility, its carrier injection barrier is comparatively high to use as electrode. In this work, we performed plasma treatment on the graphene surface and alkali metal doping in the organic materials to study for its possibility as anode and cathode, respectively. By using Ultraviolet Photoemission Spectroscopy (UPS), we investigated the interfaces of modified graphene. The plasma treatment is generated by various gas types such as O2 and Ar, to increase the work function of the graphene film. Also, for co-deposition of organic film to do alkali metal doping, we used three different organic materials which are BMPYPB (1,3-Bis(3,5-di-pyrid-3-yl-phenyl)benzene), TMPYPB (1,3,5-Tri[(3-pyridyl)-phen-3-yl]benzene), and 3TPYMB (Tris(2,4,6-trimethyl-3-(pyridin-3-yl)phenyl)borane)). They are well known for ETL materials in OLEDs. From these results, we found that graphene work function can be tuned to overcome the weakness of graphene induced carrier injection barrier, when the interface was treated with plasma (alkali metal) through the value of hole (electron) injection barrier is reduced about 1 eV.

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과맥신품종에 대한 드릴파와 시비수준이 생육 및 수량에 미치는 영향 (The Effects of the Various Fertilizer Level and Drill-Seeding on the Growth and Yield of the Newly Bred Naked-Barley)

  • 최원열;박공열
    • 한국작물학회지
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    • 제21권1호
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    • pp.9-14
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    • 1976
  • 1972년 우리나라에서 맨 처음 육성된 과맥품종으로 내한성이 强하고 다수성인 '광성'과 1974년에 육성된 단간 조숙 다수성인 방사006 두 품종을 가지고 드릴파재배에 따른 방시수준의 효과에 관한 시험결과를 요약하면 다음과 같다. 1. 관행파보다 드릴파가 종실수량이 8%나 많았고 증수요인의 하나인 수수가 현저하게 많았다. 2. 광성보다 방사006가 내도복성이 강하였다. 3. 관행파나 드릴파에서 광성보다 방사006가 시비량 증가에 따른 적응성이 높았다. 4. 품종별로 비교하던 방사006가 광성보다 종실중이 5% 높았다. 5. 시비수준별로 종실중을 비교하면 표준비에 비하여 100% 증비에서는 19% 증수되었다. 6. 드릴파 표준비에서는 광성에 비하여 방사006의 수량이 감소되었으나 증비에서는 크게 증수를 보인 내비성 품종이었다. 7. 광성보다는 방사006가 드릴파종재배에 적합한 품종으로 사료된다.

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Birth of a Siberian Tiger Cub from an Albino Mother Tiger with Help of eCG and hCG

  • Choo, Yoon-Jeong;Park, Myung-Soo;Han, Hyo-Dong;Ham, Gye-Sun;Park, Young-Sun;Kim, Gyeong-Sik;Park, Sun-Duk;Lim, Yang-Mook;Jung, So-Young;Yong, Hwan-Yul
    • 한국수정란이식학회지
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    • 제26권3호
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    • pp.215-217
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    • 2011
  • This is about the successful use of eCG and hCG for producing a Siberian tiger pup born from 10-year-old, primiparous, albino Siberian tiger. From February 2010 to July 2010, natural breeding had been tried three times with no conception. During this period of five months, estrus behaviors appeared to be typically normal and a lot of matings were observed. After consecutive failures, 1000 IU eCG (equine chorionic gonadotropin) were intramuscularly injected on the day showing estrus behavior, followed with an injection of 750 IU hCG (human chorionic gonadotropin) 80 hours later. The tiger stopped recurrence of estrus, and a cub, weighed 780 gram, was born alive 104 days after hCG injection. This study is the first report showing the unique, successful use of exogenous hormones as one of artificial breeding programs in the long history of captive breeding of carnivorous zoo animals in Korea.

마이크로스트립 라인 급전 QMSA의 특성 연구 (A Study of Microstrip Line Fed QMSA Characteristics)

  • 김은용;박옥동;류현;이남렬;박성교;박종백
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.861-864
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    • 1999
  • We designed and fabricated microstrip line fed QMSAs(Quarter-Wavelength Microstrip Antenna) for 850〔MHz〕 band on the CGP-500 Copper-clad Laminates substrate (CHUKOH company) with $\varepsilon$$_{r}$=2.6, H=1.6〔mm〕( $\pm$0.08), where the width of the radiation patch is identical with that of the ground plane. The resonant frequencies and the return losses were measured by reducing the PSW(Partially Shorted Width) to 0〔mm〕, step by step, when the microstrip line width was 1.47〔mm〕, 2.93〔mm〕and 4.4〔mm〕separately. As a result, a good characterized antenna with a 11% reduced resonant length and a return loss -29.44〔㏈〕 was obtained when the total PSW was in the range of 70% of radiated patch width, compared to the conventional QMSA.A.

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