• Title/Summary/Keyword: 결정구조 의존성

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합리적인 터널설계를 위한 정량화 지표(Multiple Index)개발 및 적용에 관한 연구

  • 위용곤;박준경;전성권;김영근
    • Proceedings of the Korean Society for Rock Mechanics Conference
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    • 2002.10a
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    • pp.31-42
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    • 2002
  • 최근 지하철 터널은 사용자 편의성, 도심지 접근성 및 원활한 교통처리 등을 고려하여 지반조건이 불리한 상황에서도 터널로 계획되는 경우가 많아지고 있다 따라서 시공중의 터널안정성확보, 굴착에 따른 인접구조물의 침하영향, 발파진동영향 등을 종합적으로 고려한 지보패턴 및 보조·보강공법의 결정이 매우 중요하나 정량적인 판단기준의 부재로 인하여 주로 경험적인 설계에 의존하는 경우가 많다. 본 연구에서는 도심지 지하철 터널의 복합적인 거동특성을 고려하기 위하여 여러 가지 예상위험요소의 정량화 방안을 제안하고, 다변량 통계분석기법을 활용하여 여러 가지 위험 요소들의 특성을 함축적으로 나타내는 소수의 총합적인 지표(안정성인자, 환경성인자)로 대표화 할 수 있음을 검증하였다. 안정성 인자 및 환경성 인자를 이용한 서울시 지하철 00공구 설계사례를 통해 정량화지표(Multiple Index)의 터널설계에의 적용성을 평가하고 이의 설계시 활용방안을 제안하고자 하였다.

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Electrical Properties of ReMnO3(Re:Y, Ho, Er) Thin Film Prepared by MOCVD Method (화학 기상 증착법으로 제조한 ReMnO3(Re:Y, Ho, Er) 박막의 전기적 특성)

  • Kim, Eung-Soo;Chae, Jung-Hoon;Kang, Seung-Gu
    • Journal of the Korean Ceramic Society
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    • v.39 no.12
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    • pp.1128-1132
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    • 2002
  • $ReMnO_3$(Re:Y, Ho, Er) thin films were prepared by MOCVD method available to non-volatile memory device with MFS-FET structure. $ReMnO_3$ thin films were deposited on the Si(100) substrate at 700${\circ}C$ for 2h. When the films were post-annealed at 900${\circ}C$ for 1h in air, the single phase of hexagonal $ReMnO_3$ thin films were detected. Ferroelectric properties of $ReMnO_3$ thin films were dependent on the degree of c-axis orientation in the single phase of hexagonal structure and remnant polarization (Pr) of $YMnO_3$ thin films with high degree of c-axis orientation was 105 nC/$cm^2$. Leakage current density was dependent on the grain size of microstructure and that of $YMnO_3$ thin films with grain size of 100∼150 nm was $10^{-8}$ A/$cm^2$ at applied voltage of 0.5 V.

A IDE based on Software Engineering Guidelines (소프트웨어 공학 가이드라인 기반 통합개발환경)

  • Choi, Seung-Yong;Hong, Chan-Ki;Kim, Jeong-Ah
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.04a
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    • pp.1009-1012
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    • 2010
  • ALM 구현을 위한 툴들 간의 통합 시도는 툴들 간의 통신 복잡성을 증가시키고 툴을 구성하는 컴포넌트 사이의 의존성과 컴포넌트 내부의 복잡성을 증가시킨다. 이는 통합개발환경의 유지보수를 어렵게 하는 결정적 원인이 된다. 따라서 본 논문은 통합개발환경 구성 컴포넌트들 간 통신 및 레이어 구조를 특성(기능) 관리 영역과 지식 관리 영역으로 이원화하고 가이드라인 MVC 모델로 구조화한 통합개발환경 아키텍처를 제시한 소프트웨어 공학 가이드라인 기반 통합개발환경 모델을 제안한다. 제안한 모델은 통합개발환경 구성 컴포넌트의 재사용성, 확장성, 유지보수성 향상과 더불어 통합개발환경 개발/관리자에게 효율적인 개발/관리 지침을 제공한다.

Temperature Dependence of Bonding Structure of GZO Thin Film Analyzed by X-ray Diffractometer (XRD의 결정구조로 살펴본 GZO 박막의 온도의존성)

  • Oh, Teresa
    • Journal of the Semiconductor & Display Technology
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    • v.15 no.1
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    • pp.52-55
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    • 2016
  • GZO film was prepared on p-type Si wafer and then annealed at various temperatures in an air conditions to research the bonding structures in accordance with the annealing processes. GZO film annealed in an atmosphere showed the various bonding structure depending on annealing temperatures and oxygen gas flow rate during the deposition. The difference of bonding structures of GZO films made by oxygen gas flows between 18 sccm and 22 sccm was so great. The bonding structures of GZO films made by oxygen gas flow of 18 sccm were showed the crystal structure, but that of 22 sccm were showed the amorphous structure in spite of after annealing processes. The bonding structure of GZO as oxide-semiconductor was observed the trend of becoming amorphous structures at the temperature of $200^{\circ}C$. Therefore, the characteristics of oxide semiconductor are needed to research the variation near the annealing at $200^{\circ}C$.

Different morphologies of three dimensional ZnO structures synthesized by thermal evaporation method without a catalyst (촉매를 사용하지 않는 열 기화법으로 다양한 형태의 ZnO 3차원 구조체 합성)

  • Bang, Sin Young;Tran, Van Khai;Oh, Dong Keun;Maneeratanasarn, Prachuporn;Choi, Bong Geun;Ham, Heon;Kim, Kyoung Hun;Shim, Kwang Bo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.23 no.1
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    • pp.8-13
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    • 2013
  • ZnO with different morphologies can be used various application depending on their shapes. Different morphologies of ZnO structures were synthesized by a catalysis-free thermal evaporation process. Their morphologies were dependent on the distance from the source to substrate on the same processing condition; in the result were products morphologies of the hollow, cage and star. Their shapes and crystalinity were evaluated by SEM and XRD, respectively. This work demonstrates what kind of growth factors would be involved in the final structure morphologies.

Silica-encapsulated ZnSe Quantum Dots as a Temperature Sensor Media (온도센서용 실리카에 담지된 ZnSe 양자점 소재)

  • Lee, Ae Ri;Park, Sang Joon
    • Applied Chemistry for Engineering
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    • v.26 no.3
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    • pp.362-365
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    • 2015
  • Silica encapsulated ZnSe quantum dots (QDs) were prepared by employing two microemulsion systems: AOT/water/cyclohexane microemulsions containing ZnSe quantum dots with NP5/water/cyclohexane microemulsions containing tetraethylorthosilicate (TEOS). Using this method, cubic zinc blende nanoparticles (3 nm in diameter) were synthesized and encapsulated by silica nanoparticles (20 nm in diameter). The temperature dependence of photoluminescence (PL) for silica-encapsulated ZnSe QDs was investigated to evaluate this material as a temperature sensor media. The fluorescence emission intensity of silica-encapsulated ZnSe nanoparticles (NPs) was decreased with an increase of ambient temperature over the range from $30^{\circ}C$ to $60^{\circ}C$ and a linear relationship between the temperature and the emission intensity was observed. In addition, the temperature dependence of PL intensity for silica-encapsulated ZnSe NPs showed a reversible pattern on ambient temperature. A reversible temperature dependence of the luminescence combined with its insensitivity toward quenching by oxygen due to silica coating established this material as an attractive media for temperature sensor applications.

A Study on the Preparation of UPE Resins with Different Glycol Molar Ratios and Their Physical Properties : 3. Estimation of Viscoelastic and Critical Surface Tension of UPE Liquid Resins (글리콜 몰비가 다른 불포화 폴리에스테르 수지의 제조 및 물성에 관한 연구 : 3. UPE 액상 수지의 임계표면장력 및 점탄성 평가)

  • 이상효;안승국;이장우
    • Polymer(Korea)
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    • v.24 no.5
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    • pp.589-598
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    • 2000
  • In this study, various unsaturated polyester (UPE) resins were prepared from the condensation polymerization of mixtures of saturated (isophthalic acid : IPA) and unsaturated (maleic anhydride : MA) dibasic acids with propylene glycol (PG), neopentyl glycol (NPG). The critical surface tension (Υ$_{c}$) for the surface characteristics of a solid were estimated by Zisman plot, and the structure-property relationship was investigated by measuring the rheology of resins. The values of Υ$_{c}$ for glass of solid were 30.5 mNㆍm$^{-1}$ for UPE resin liquids. As the content of NPG in a PG/NPG glycol mixture increased, both the contact angle and the surface tension of the UPE resin liquids were found to decrease. The dynamic viscoelasticities of UPE resins with different glycol molar ratios were also measured. Shear rate dependence of viscosity and angular frequency dependence of storage, and loss modulus tended to decrease with increasing NPG content.

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3-D Analysis of Semiconductor Surface by Using Photoacoustic Microscopy (광음향 현미경법을 이용한 반도체 표면의 3차원적 구조 분석)

  • Lee, Eung-Joo;Choi, Ok-Lim;Lim, Jong-Tae;Kim, Ji-Woong;Choi, Joong-Gill
    • Journal of the Korean Chemical Society
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    • v.48 no.6
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    • pp.553-560
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    • 2004
  • In this experiment, a three dimensional structure analysis was carried out to examine the surface defects of semiconductor made artificially on known scale. It was investigated the three dimensional imaging according to the sample depth and the thermal diffusivity as well as the carrier transport properties. The thermal diffusivity measurement of the intrinsic GaAs semiconductor was also analyzed by the difference of frequency-dependence photoacoustic signals from the sample surface of different conditions. Thermal properties such as thermal diffusion length or thermal diffusivity of the Si wafer with and without defects on the surface were obtained by interpreting the frequency dependence of the PA signals. As a result, the photoacoustic signal is found to have the dependency on the shape and depth of the defects so that their structure of the defects can be analyzed. This method demonstrates the possibility of the application to the detection of the defects, cracks, and shortage of circuits on surface or sub-surface of the semiconductors and ceramic materials as a nondestructive testing(NDT) and a nondestructive evaluation(NDE) technique.

Exploiting Chunking for Dependency Parsing in Korean (한국어에서 의존 구문분석을 위한 구묶음의 활용)

  • Namgoong, Young;Kim, Jae-Hoon
    • KIPS Transactions on Software and Data Engineering
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    • v.11 no.7
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    • pp.291-298
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    • 2022
  • In this paper, we present a method for dependency parsing with chunking in Korean. Dependency parsing is a task of determining a governor of every word in a sentence. In general, we used to determine the syntactic governor in Korean and should transform the syntactic structure into semantic structure for further processing like semantic analysis in natural language processing. There is a notorious problem to determine whether syntactic or semantic governor. For example, the syntactic governor of the word "먹고 (eat)" in the sentence "밥을 먹고 싶다 (would like to eat)" is "싶다 (would like to)", which is an auxiliary verb and therefore can not be a semantic governor. In order to mitigate this somewhat, we propose a Korean dependency parsing after chunking, which is a process of segmenting a sentence into constituents. A constituent is a word or a group of words that function as a single unit within a dependency structure and is called a chunk in this paper. Compared to traditional dependency parsing, there are some advantage of the proposed method: (1) The number of input units in parsing can be reduced and then the parsing speed could be faster. (2) The effectiveness of parsing can be improved by considering the relation between two head words in chunks. Through experiments for Sejong dependency corpus, we have shown that the USA and LAS of the proposed method are 86.48% and 84.56%, respectively and the number of input units is reduced by about 22%p.

Definition and Evaluation of Korean Phone-Like Units using Hidden Markov Network (HM-Net을 이용한 한국어 유사음소 단위의 재 정의와 평가)

  • Lim Young-Chun;Oh Se-Jin;Jung Ho-Youl;Chung Hyun-Yeol
    • Proceedings of the Acoustical Society of Korea Conference
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    • spring
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    • pp.183-186
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    • 2002
  • 최근 음성인식의 인식 단위로서 문맥의존 음향 모델이 널리 사용되고 있다. 이는 음소의 음향학적 특징, 즉 선행 및 후행음소에 의한 중심 음소의 변이음 모델이 문맥독립 모델보다 좀 더 정확하게 모델링 될 수 있기 때문이다. 하지만 강건한 문맥의존 음향 모델을 작성하기 위해서는 모델 파라미터의 병합(tying)과 미지의 문맥(unseen context)의 처리를 위한 좀더 정교한 해결 방법이 필요하다. 따라서 본 논문에서는 이점을 고려하여 음향학적 특징과 언어학적 특징을 결합하여 상태 분할을 수행할 수 있도록 SSS(Successive State Splitting) 알고리즘의 문맥 방향 상태 분할에 음소결정트리를 접목한 HM-Net(Hidden Markov Network) 구조 결정법을 도입하였다. 또한 HM-Net은 연속적인 상태 분할에 의해 한국어에서 많이 발생하는 변이음들을 효과적으로 모델링 할 수 있다는 점을 고려하여 본 연구실에서 기존에 사용하던 48 유사음소 단위에서 문맥의존 음향 모델 작성에 불필요한 변이음을 제거하여 39 유사음소 단위를 재 정의하였다. 도입한 방법과 새로 정의한 유사음소 단위의 유효성을 확인하기 위해 고립 단어, 4연속 숫자음, 연속 음성인식에 대해 인식 실험을 수행한 결과, 모든 실험에서 재 정의한 39 유사음소 단위가 문맥종속형 HM-Net 음향모델을 이용한 한국어 음성인식에 효과적임을 확인할 수 있었다. 특히 연속 음성인식 실험의 경우, 기존의 48 유사음소 단위보다 평균 $15.08\%$의 인식률 향상이 있었다.

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