• Title/Summary/Keyword: Structure Transformation

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A Small-Area ISDB-T Time Deinterleaver Structure with Buffer Transformation (버퍼 변환을 이용한 저면적 ISDB-T 시간 디인터리버 구조)

  • Kang, Hyeong-Ju
    • Journal of Advanced Navigation Technology
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    • v.15 no.2
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    • pp.227-233
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    • 2011
  • This paper presents a small-area ISDB-T time deinterleaver structure. ISDB-T is an mobile TV standard that is widely used in Japan and many South American countries. One of the strong points of the standard is the long interleaving depth, which enhance the communication performance. However, long interleaving requires many delay buffers, in other words many pointer registers. This paper reduces the number of pointer registers with the deinterleaver equivalent transformation. The experimental results show that the area is reduced with the proposed structure.

Diffraction Characteristics of Mechanically Alloyed Nanocrystalline FeAl (기계적합금화한 FeAl 나노결정립의 회절특성)

  • Choi, Keun-Seob;Kim, Do-Hyang;Hong, Kyung-Tae
    • Applied Microscopy
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    • v.27 no.4
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    • pp.473-481
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    • 1997
  • Disorder-order transformation of nanocrystalline FeAl have been investigated by a combination of electron and X-ray diffraction analysis including high resolution electron microscopy and differential scanning calorimetry. Fe-50at.%Al powders mechanically alloyed for 90 hours consist of $5\sim10$ nm size grains haying either disordered b.c.c. structure or amorphous structure. X-ray and electron diffraction of mechanically alloyed FeAl powders show that disorder-order transformation occurs at the temperature range of $300^{\circ}C\sim320^{\circ}C$. Such a low-temperature ordering behavior exhibiting an exothermic reaction is attributable to the nm-scale grain structure with a large amount of defects accumulated during mechanical alloying process.

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An Investigation of the Transformation Sequence from Kaolinite to Mullite (카올리나이트의 상전이반응 과정 연구)

  • 이수정;김윤중;문희수
    • Journal of the Mineralogical Society of Korea
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    • v.11 no.1
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    • pp.32-44
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    • 1998
  • The transformation sequence of kaolinite to mullite is examined with new electron diffraction data obtained mainly by an energy filtering transmission electron microscope. Kaolinite is transformed finally into mullite and cristobalite through several steps of continuous reactions by heating, which result in metakaolinite, microcrystalline spinel-type phase and amorphous silica. Metakaolinite maintains a short-range order in its structure ven at $920^{\circ}C$. Spinel phase results from a topotactictransformation of metakaolinite apart from the breakdown of metakaolinite structure. the first strong exothermic peak on DTA curve is mainly due to the extraction of amorphous silica from metakaolinite and the gradual nucleation of mullite. Metakaolinite decomposes around$ 940^{\circ}C$ to mullite that doesn't show a clear crystallographic relationship to the parent metakaolinite structure. However, spinel phase produced previously is maintained. The initially formed spinel and mullite phases are suggested to be Al-rich, but progressively gain Si in their structures at higher temperatures. Spinel phase decomposes completely through a second weak exothermic reaction promoting the growth of mullite, and crystallization of amorphous silica to cristobalite.

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Influence of soil-structure interaction on seismic responses of offshore wind turbine considering earthquake incident angle

  • Sharmin, Faria;Hussan, Mosaruf;Kim, Dookie;Cho, Sung Gook
    • Earthquakes and Structures
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    • v.13 no.1
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    • pp.39-50
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    • 2017
  • Displacement response and corresponding maximum response energy of structures are key parameters to assess the dynamic effect or even more destructive structural damage of the structures. By employing them, this research has compared the structural responses of jacket supported offshore wind turbine (OWT) subjected to seismic excitations apprehending earthquake incidence, when (a) soil-structure interaction (SSI) has been ignored and (b) SSI has been considered. The effect of earthquakes under arbitrary angle of excitation on the OWT has been investigated by means of the energy based wavelet transformation method. Displacement based fragility analysis is then utilized to convey the probability of exceedance of the OWT at different soil site conditions. The results show that the uncertainty arises due to multi-component seismic excitations along with the diminution trend of shear wave velocity of soil and it tends to reduce the efficiency of the OWT to stand against the ground motions.

UML Class Diagram for XDR Schema (XDR 스키마를 위한 UML 클래스 다이어그램)

  • Yoo Moon-sung
    • Journal of Internet Computing and Services
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    • v.4 no.4
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    • pp.35-44
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    • 2003
  • XML becomes the standard for exchanging documents and data on the Web. Schema is used to define XML documents. Among schema, XDR schema, developed chiefly by Microsoft, is a leading schema for practical use. UML is a notation in object-oriented software development and a useful tool to represent the structure of a system. In this paper, we study the transformation method and algorithm from XDR schema to UML diagram. By this transformation, the structure of XDR schema is represented graphically. Thus we can easily understand the structure of XDR schema and we can create XML documents effectively by enhancing reusability and flexibility.

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A Study on the Formation of Working-Class Residential Areas md the Transformation of Housing Types of Firenze, Italy (이탈리아 피렌체의 서민주거지역의 형성과 주거형식의 변화에 관한 연구)

  • Sohn, Sei-Kwan
    • Journal of architectural history
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    • v.13 no.2 s.38
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    • pp.21-38
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    • 2004
  • This study provides a descriptive and analytical account of major aspects of urban development and transformation of housing types of Italian Firenze from the 13th century to the 19th century. It is a typo-morphological depiction of urban spatial structure of the extraordinary city, Firenze, the center of Italian Renaissance. And this study has proceeded on the assumption that the evolving form of the urban structure and housing types cannot be understood without reference to the larger context of political, economic, and social life. Based on these backgrounds, the purpose of this study is threefold: to provide a comprehensive discussion of general characteristics of urban spatial structure of Firenze, and to explain the process of formation of working-class neighborhoods by constructing new city wall in later 13th century, and to discuss transformation of housing types of the working-class neighborhood with understanding the mechanism of existence of housing in the newly formed residential neighborhoods. The development of residential neighborhoods was pursued by 'planned' manner through forming square-shaped blocks, and characterized by the subdivision of larger properties into standardized building lots for the construction of houses. On the bases of documentary evidences, several ecclesiastical institutions are identified as the agents of a distinctive type of development. While the institutions did the major role for developing lands, the construction of houses was done by small scale construction agents with moderate amount of properties. The major housing type of working-class neighborhoods of Firenze has been the 'casa a schiera' characterized by the form of narrow front and long depth. The type was generalized by the newly formed middle and working-class of Firenze which grew their body very rapidly, Even though the type assumed very uniform in its fen there were many variations. And through passing time, the casa a schiera developed to be multi-family housing, and the level of variation became deepen. Eventually, transformation of housing type of Firenze was ended by appearance of the 'casa in linea', which was very similar to modern apartment in its spatial organization.

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XML Schema Transformation Considering Semantic Constraint (의미적 제약조건을 고려한 XML 스키마의 변환)

  • Cho, Jung-Gil
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.3
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    • pp.53-63
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    • 2011
  • Many techniques have been proposed to store and query XML data efficiently. One way achieving this goal is using relational database by transforming XML data into relational format. It is important to transform schema to preserve the content, the structure and the constraints of the semantics information of the XML document. Especially, key constraints are an important part of database theory. Therefore, the proposal technique has considered the semantics of XML as expressed by primary keys and foreign keys. And, the proposal technique can preserve not only XML data constraints but also the content and the structure and the semantics of XML data thru transformation process. Transforming information is the content and the structure of the document(the parent-child relationship), the functional dependencies, semantics of the document as captured by XML key and keyref constraints. Because of XML schema transformation ensures that preserving semantic constraints, the advantages of these transformation techniques do not need to use the stored procedure or trigger which these data ensures data integrity in the relational database. In this paper, there is not chosen the ID/IDREF key which supported in DTD, the inheritance relationship, the implicit referential integrity.

Formation of Ferrite-Cementite Microstructure by Strain Induced Dynamic Transformation in Medium Carbon Steels (중 탄소강의 변형유기 동적변태에 의한 페라이트-시멘타이트 형성거동에 대한 연구)

  • Lee Y. H.;Lee D. L.;Choo W. Y.;Lee C. S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2004.10a
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    • pp.211-214
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    • 2004
  • In the present study, the effect of SIDT (Strain Induced Dynamic Transformation) on the microstructure of medium carbon steels was investigated to develop spheroidized annealing-free steel wire rods. When $0.45\%C$ steels were hot-deformed under the conditions of heavy reduction at low temperatures, a microstructure quite different from conventional ferrite-pearlite structure was obtained. It was considered that this ferrite-cementite microstructure was obtained because very small retained austenite grains existing between fine SIDT ferrites prefer to transform to cementite and ferrite instead of pearlite during cooling. Through the present study, $0.45\%C$ steels containing ferrite-cementite (FC) structure instead of ferrite-pearlite structure was obtained in as-rolled state by introducing SIDT. The specimen containing the FC structure was much softer than that containing conventional ferrite-pearlite structure. Therefore, it is concluded that deforming medium carbon steels under the conditions of SIDT is a very powerful method to obtain soft steel wire rods which could be cold-forged without softening heat-treatment

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A Study on the Transformation of Traditional Houses in Seongeup Folk Village in Jeju (성읍민속마을 민가의 안거리 평면변용에 관한 연구)

  • Sung, Dae-Chul;Lee, Sang-Sun
    • Journal of the Korean Institute of Rural Architecture
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    • v.14 no.1
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    • pp.99-106
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    • 2012
  • Transformation which is the major damage factor of living space in folk village is caused by improvement behaviors reflecting real requirements of residents who are the subjects of life. Such a process changes traditional space structure gradually and lowers preservative value of folk village. Therefore this study examines transformational conditions of living space centering around changes of spatial components and plane forms through literature and field research and analyzes characteristics of transformational phenomenon. This study examined changes of components and transformation of Seongeup folk village. While main room plane was diversified by residents' requirements, it was not harmonized with traditional image of Seongeup folk village. Transformation of living space at Seongeup Folk Village was positive from the side of residents' living requirements, but negative in that it damaged unique identity of folk village. Accordingly, it is thought that deliberation considering residents' living requirements as the field of their life with maintenance of original form for the purpose of preserving folk village and professionals' support and legal study for revision of approval system are continuously required.

Molecular Dynamic Simulation of Nano Indentation and Phase Transformation (분자동역학을 이용한 나노 인덴테이션과 상변화 해석 연구)

  • 김동언;손영기;임성한;오수익
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2003.10a
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    • pp.339-346
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    • 2003
  • Molecular dynamic simulations of nano indentation on single-crystal silicon (100) surface were performed using diamond indentor. Silicon substrate and diamond indentor were modeled diamond structure with Tersoff potential model. Phase transformation of silicon, incipient plastic deformation, change of incident temperature distribution are investigated through the change of potential energy distribution, displacement-load diagram, the change of kinetic energy distribution and displacements of silicon atoms. Phase transformation is highly localized and consists of a high-density region surrounding the tip. Axial load linearly increased according to the indenting depth. Number of atoms with high kinetic energy increased at the interface between substrate and indentor tip.

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