• 제목/요약/키워드: Inter-Korean

검색결과 6,046건 처리시간 0.03초

초저온 케스케이드 냉동사이클의 중간압력 및 바이패스 유량 최적화 (Optimization of Middle Pressure and Bypass Mass Flow Rate in Cryogenic Refrigeration Cascade Cycle)

  • 오승택;최원재;이호생;윤정인;유선일;최건형;이상규
    • 동력기계공학회지
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    • 제14권2호
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    • pp.28-33
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    • 2010
  • In this research, cascade liquefaction process was simulated using two-staged direct expansion with inter-cooler. Evaporated gaseous refrigerant which has low pressure and temperature from the inter-cooler is mixed with gaseous refrigerant from outlet of 1st compressor, and flows into 2nd compressor. Therefore this prevents superheating compression. Compressor work of process which includes inter-cooler to all cycles shows the lowest value of 338.68 MW and it is lower 16.34% than that of basic process. Refrigeration capacity shows decreasing tendency as applied inter-cooler and that of process which includes inter-cooler to all cycles shows the lowest value of 449 MW. COP was increased when the inter-cooler was applied, and process which includes inter-cooler to all cycles shows highest value of 1.33. It shows that COP was increased because decrement of compressor work by applying inter-cooler was higher than decrement of refrigeration capacity.

Development of the Korean Handwriting Assessment for Children Using Digital Image Processing

  • Lee, Cho Hee;Kim, Eun Bin;Lee, Onseok;Kim, Eun Young
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제13권8호
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    • pp.4241-4254
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    • 2019
  • The efficiency and accuracy of handwriting measurement could be improved by adopting digital image processing. This study developed a computer-based Korean Handwriting Assessment tool. Second graders participated in this study by performing writing tasks of consonants, vowels, words, and sentences. We extracted boundary parameters for each letter using digital image processing and calculated the variables of size, size coefficient of variation (CV), misalignment, inter-letter space, inter-word space, and ratio of inter-letter space to inter-word space. Children were also administered traditional handwriting and visuomotor tests. Digital variables from image processing were correlated with these previous tests. Using these correlations, we established a three-point scoring system that computed test scores for each variable. We analyzed inter-rater reliability between the computer rater and human rater and test-retest reliability between the first and second performances. The validity was examined by analyzing the relationship between the Korean Handwriting Assessment and previous handwriting and visuomotor tests. We suggested the Korean Handwriting Assessment to measure size, size consistency, misalignment, inter-letter space, inter-word space, and space ratio using digital image processing. This Korean Handwriting Assessment tool proved to have reliability and validity. It is expected to be useful for assessing children's handwriting.

가변형 박막 유전체에 전극을 임베디드 시킨 고가 변형 커패시터 (A High Tunable Capacitor Embedding Its Electrodes in Tunable Thin Film Dielectrics)

  • 이영철;홍영표;고경현
    • 한국전자파학회논문지
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    • 제17권9호
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    • pp.860-865
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    • 2006
  • 본 논문에서는 가변형 $Bi_2O_3-ZnO-Nb_2O_5(BZN)$ Pyrochlore 박막을 이용한 고가변형 inter-digital capacitor를 제안하였다. 가장자리 전계 효과를 이용한 가변성의 향상과 DC 전압의 감소를 위해 inter-digital capacitor의 전극이 박막 내부에 삽입되었다. 2.5D simulator를 이용한 설계 결과, 제 안된 구조의 inter-digital capacitor(IDC)가 일반적인 구조의 IDC에 비해 가변성이 10 % 향상되었다. 제안된 IDC는 설계 결과를 바탕으로 실리콘 기판 위에 BZN 박막을 이용하여 제작되었다. BZN 박막은 reactive RF magnetron sputtering 방법을 이용하여 증착되었다. 제작된 inter-digital capacitor는 5.8 GHz와 18 V의 DC 인가 전압에서 최대 가변율이 50 %였다.

Inter-Pillar 진동 모드를 고려한 1-3형 압전복합체의 구조 최적화 (Optimization of 1-3 Type Piezocomposite Structures Considering Inter-Pillar Vibration Modes)

  • 표성훈;김진욱;노용래
    • 한국전기전자재료학회논문지
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    • 제26권6호
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    • pp.434-440
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    • 2013
  • With polymer properties and ceramic volume fraction as design variables, the optimal structure of 1-3 piezocomposites has been determined to maximize the thickness mode electromechanical coupling factor. When the piezocomposite vibrates in a thickness mode, inter-pillar resonant modes are likely to occur between lattice-structured piezoceramic pillars and polymer matrix, which significantly deteriorates the performance of the piezocomposite. In this work, a new method to design the structure of the 1-3 type piezocomposite is proposed to maximize the thickness mode electromechanical coupling factor while preventing the occurrence of the inter-pillar modes. Genetic algorithm was used for the optimal design, and the finite element analysis method was used for the analysis of the inter-pillar mode.

Up/Downlink Hybrid Inter-Cell Coordination Patterns of the TDD/MC-CDMA System, TDD/MC-CDMA

  • 한상진;이성진;이상훈;길계태
    • 한국통신학회논문지
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    • 제34권5A호
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    • pp.421-428
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    • 2009
  • Inter-cell coordination has been an emerging issue for mitigating inter-cell interference in broadband wireless access networks such as IEEE802.16 and 3GPP LTE (Long Term Evolution). This paper proposes uplink/downlink hybrid inter-cell coordination patterns for a TDD (Time Division Duplex)/MC-CDMA (Multi-Carrier Code Division Multiple Access) system. For the performance analysis, closed forms of inter-cell interferences are derived when uplink and downlink transmissions coexist over a multi-cell environment. In the analysis, we find an optimal ratio of downlink transmit powers of BSs (Base Stations) based on the target outage probability and the performance according to ratios of uplink/downlink transmit powers of MSs (Mobile Stations)/BSs is explored. Our numerical results show that interference mitigation utilizing the characteristics of the uplink and downlink power ratio is very effective in improving system performance in terms of QoS.

Triple Layer Passivation for Organic Thin-Film Transistors

  • Ryoo, Ki-Hyun;Lee, Cheon-An;Jin, Sung-Hun;Jung, Keum-Dong;Park, Chang-Bum;Lee, Jong-Duk;Shin, Hyung-Cheol;Park, Byung-Gook
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1310-1312
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    • 2005
  • Passivation of organic thin-film transistors (OTFTs) using organic and metal thin-film was presented. Parylene-C and titanium were used as an organic and metal layer, respectively. With the proposed passivation method the degradation of electric parameters of OTFTs was relieved compared with non-passivated devices. Several electric parameters such as on/off current, field-effect mobility, and threshold voltage were shown.

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Electrical performance and contact resistance with the substrate temperature in the pentacene organic thin-film transistors

  • Lee, Cheon-An;Jang, Kyoung-Chul;Kim, Sung-Won;Ryoo, Ki-Hyun;Jin, Sung-Hun;Lee, Jong-Duk;Shin, Hyung-Cheol;Park, Byung-Gook
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1317-1319
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    • 2005
  • Bottom contact pentacene organic thin-film transistors are fabricated at three different substrate temperatures, $70^{\circ}C$, $80^{\circ}C$ and $90^{\circ}C$. The maximum effective mobility was obtained at $80^{\circ}C$. The contact resistance was extracted by applying two different methods, TLM method and channel-resistance method, and the value shows the minimum at $80^{\circ}C$, which is thought to be the important reason for the best performance.

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Assessing Resilience of Inter-Domain Routing System under Regional Failures

  • Liu, Yujing;Peng, Wei;Su, Jinshu;Wang, Zhilin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권4호
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    • pp.1630-1642
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    • 2016
  • Inter-domain routing is the most critical function of the Internet. The routing system is a logical network relying on the physical infrastructure with geographical characteristics. Nature disasters or disruptive accidents such as earthquakes, cable cuts and power outages could cause regional failures which fail down geographically co-located network nodes and links, therefore, affect the resilience of inter-domain routing system. This paper presents a model for regional failures in inter-domain routing system called REFER for the first time. Based on REFER, the resilience of the inter-domain routing system could be evaluated on a finer level of the Internet, considering different routing policies of intra-domain and inter-domain routing systems. Under this model, we perform simulations on an empirical topology of the Internet with geographical characteristics to simulate a regional failure locating at a city with important IXP (Internet eXchange Point). Results indicate that the Internet is robust under a city-level regional failure. The reachability is almost the same after the failure, and the reroutings occur at the edge of the Internet, hardly affecting the core of inter-domain routing system.

남북상사중재 제도 활성화를 위한 남북협력방안 -북한의 대외경제중재법(1980) 평가를 중심으로- (A Study on Cooperation Ways of South-North Korea for Revitalization of Inter-Korean Commercial Arbitration System - Centering around Evaluation of the Foreign Economic Arbitration Act(2008) of North Korea -)

  • 김광수
    • 한국중재학회지:중재연구
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    • 제21권1호
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    • pp.259-277
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    • 2011
  • In 2008, North Korea revised its Foreign Economic Arbitration Act. To some extent, the new Act reflected such international standard of arbitration as UNCITRAL Arbitration Rules. In this paper, the said Act will be evaluated, and then cooperation ways of South-North Korea on Inter-Korean Commercial Arbitration will be suggested. In 2007, the Ministry of Unification has designated the Korean Commercial Arbitration Board as Inter-Korean Arbitration Committee and has made efforts to prepare follow-up measures on the two Agreements of Inter-Korean Commercial Arbitration. In 2008 however, the follow-up measures has in fact been suspended. In order to revitalize the Inter-Korean commercial arbitration, some prerequisites must be satisfied. First, Inter-Korean Arbitration Committee for Inter-Korean commercial arbitration should re-open as soon as possible. Second, as North Korea recently shows interest in joining the New York Convention on the Recognition and Enforcement of Foreign Arbitral Awards(now so called New York Convention), Governmental Authority of Rep. of Korea should also actively assist and support their joining in New York Convention. Third, both Korean governments should carry out joint study on raising the efficiency of the arbitration system which they will use. Fourth, comparative study on arbitration systems used in both countries should be conducted. Also, it may is very timely to discuss the issue in international arbitration community such as "North-East Asia International Arbitration Conference" or other similar events. In conclusion, continuous study on prevention of commercial disputes between South-North Korea and ways to resolve disputes when they arise should be conducted.

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Inter-Level Causal Reasoning in Stock Price Index Prediction Model

  • Kim, Myoung-Jong;Ingoo Han
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 1998년도 추계학술대회 논문집
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    • pp.224-227
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    • 1998
  • This paper proposes inter-level causal reasoning to implement synergistic approach. We decompose KOSPI prediction model into economy and industry level. Two kinds of intra-level QCOM are combined in inter-level QCOM via Inter-level relations. Downward reasoning is achieved by propagating the disturbance in the higher level to lower level while upward reasoning is to analyze the reverse cases.

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