• 제목/요약/키워드: Functional block

검색결과 401건 처리시간 0.024초

한국형 고속열차 추진시스템의 신뢰성 평가 (Reliability Assessment of Traction System of Korean High Speed Train)

  • 서승일;박춘수;한영재;이태형;김기환
    • 한국철도학회논문집
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    • 제8권5호
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    • pp.434-438
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    • 2005
  • In this paper, as the first step to assess and enhance the reliability of Korea High Speed Train, an electric traction system is selected and reliability analysis is carried out. The electric traction system is classified into subsystems and functional block diagrams and reliability block diagrams are drawn. Expressions for evaluating the reliability are derived and Mean Kilometer Between Service Failure is calculated using the trial track test results. The calculation results show reliability growth of the proposed system.

Thermally Induced Mesophase Development in Ethanesilica Films via Macromolecular Templating Approach

  • Cho, Whirang;Char, Kook-Heon;Kwon, Su-Yong
    • Macromolecular Research
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    • 제17권9호
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    • pp.697-702
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    • 2009
  • Mesoporous ethanesilica thin film was prepared using PEO-PLGA-PEO triblock copolymers as structure-directing agents and (1,2-bis(triethoxysilyl) ethane BTESE; bridged organosilicates) as inorganic precursors via one-step sol-gel condensation of ethanesilica precursors. The mesostructure of ethanesilica films is critically dependent on the processing experimental parameters after the hydrolyzed silica sol mixture was spin-cast. This study examined the effects of the block copolymer template/organosilica precursor ratio in the casting solution and aging period before calcination of the mesostructure. It was further demonstrated that mesoscopic ordering of organosilicate thin films is induced by the rearrangement of block copolymer template/organosilica hybrid during thermal decomposition of the PEO-PLGA-PEO triblock copolymer. The mesoporous structure and morphology were characterized by SAXS, TEM and solid-state NMR measurement.

Thermoresponsive Phase Transitions of PLA-block-PEO-block-PLA Triblock Stereo-Copolymers in Aqueous Solution

  • Lee, Hyung-Tak;Lee, Doo-Sung
    • Macromolecular Research
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    • 제10권6호
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    • pp.359-364
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    • 2002
  • A series of PLA-PEO-PLA triblock stereo-copolymers with varying PLA/PEO and L-DL-LA ratios were synthesized via ring opening pelymerizations. Aqueous solutions of these copolymers undergo thermo-responsive phase transitions as the temperature monotonically increases. Further study shows that there is a critical gel concentration (CGC), and also lower and upper critical gel temperatures (CGTs), at which the thermo-responsive phase transition occurs. The CGC and CGTs are affected by various factors such as block length, as well as the compositions of the PLA blocks and of the additives. In particular, the changes in the phase diagram produced by varying the L-/DL-LA ratio in the PLA blocks were determined to be mainly due to consequent stereo-regularity changes in the PLA blocks.

Fabrication of Colloidal Clusters of Polymer Microspheres and Nonspherical Hollow Micro-particles from Pickering Emulsions

  • Cho, Young-Sang;Kim, Tae-Yeol;Yi, Gi-Ra;Kim, Young-Kuk;Choi, Chul-Jin
    • Bulletin of the Korean Chemical Society
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    • 제33권1호
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    • pp.159-166
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    • 2012
  • We have introduced the Pickering emulsion systems to generate novel confining geometries for the selforganization of monodisperse polymer microspheres using nanoparticle-stabilized emulsion droplets encapsulating the building block particles. Then, through the slow evaporation of emulsion phases by heating, these microspheres were packed into regular polyhedral colloidal clusters covered with nanoparticle-stabilizers made of silica. Furthermore, polymer composite colloidal clusters were burnt out leaving nonspherical hollow micro-particles, in which the configurations of the cluster structure were preserved during calcination. The selfassembled porous architectures in this study will be potentially useful in various applications such as novel building block particles or supporting materials for catalysis or gas adsorption.

Block Copolymer Thin Films: Nanotemplates for New Functional Nanomaterials

  • Kim, Jin-Kon;Lee, Jeong-In;Yang, Seung-Yun
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.81-82
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    • 2006
  • In this study, the applications of the block copolymer thin films are introduced. For this purpose, we first obtained cylindrical nanodomains in polystyrene-block-poly(methyl methacrylate) copolymer perpendicularly oriented to a substrate. Then, nanoporous templates were prepared after removing the PMMA nanodomains by UV treatment. By using electropolymerization, high density nanowire arrays of conducting polymer of poly(pyrrole) and poly( 3-hexyl thiopene) were obtained and their electric properties were measured. Also, these nanoporous thin films were found to be very useful for the separation of human Rhinovirus type 14 (HRV 14), major pathogen of a common cold in humans, from the buffer solution.

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비선형 시스템 해석을 위한 볼테라 시리지의 응용 (Application of Volterra functional series to the analysis of nonlinear systems)

  • 성단근
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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    • pp.145-149
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    • 1987
  • The input-output relation for nonlinear systems can be explicitly represented by the Voltera functional series and it is characterized by the Volterra Kernels. A block diagram reduction method is introduced to determine the Volterra Kernels for the nonlinear systems represented by nonlinear differential equations. Degree of nonlinearity is defined and analyzed for the analysis of nonlinear systems.

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멀티모드 단말기의 라디오 라이브러리를 위한 표준 기능 블록의 선정 및 구현 (Selection and implementation of Standard Functional Blocks for Radio Library in multi-mode mobile device)

  • 정일도;최승원
    • 디지털산업정보학회논문지
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    • 제12권3호
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    • pp.125-132
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    • 2016
  • The European Telecommunication Standards Institute (ETSI) Technical Committee (TC) Reconfigurable Radio Systems (RRS) is standardizing the multi-mode Mobile Device (MD). The configuration of multi-mode MD is determined by the downloaded mobile communication standard software. In this paper, we introduce the Radio Library concept for multi-mode MD which is one of the key components of RRS standard. This paper also introduces the Standard Functional Block which is a part of Radio Library. A method for selecting efficiency SFBs for multi-mode MD is presented and a Radio Library is generated based on the selected SFBs. This paper also shows sample Standard Functional Block Set which included in Radio Library. In order to verify the compatibility of the generated Radio Library which was made by C language, we implement the LTE Rel-10 and Wi-Fi(802.11b) to show the efficiency of generating a mobile communication standard software based on the Radio Library. Then using the Prograph Visual Programming MartenTM 1.6.4, we compiled our LTE Rel-10 and Wi-Fi(802.11b) source code.

Physical Therapy and Rehabilitation of Complex Regional Pain Syndrome in Shoulder Prosthesis

  • Celik, Derya;Demirhan, Mehmet
    • The Korean Journal of Pain
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    • 제23권4호
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    • pp.258-261
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    • 2010
  • We report a 66-year-old woman with complex regional pain syndrome (CRPS) 1 treated with combined medical and active physical therapy. She was diagnosed with CRPS 1 following partial shoulder prosthesis due to proximal humerus fracture. Despite continuous medication and physical therapy, there was no improvement in her pain and functional outcome. Her overall pain was decreased by stellate ganglion block 3 times in two weeks conducted during the second month of the follow-up period. Following the ganglion blockades, pain and the other symptoms were decreased intermittently but range of motion (ROM) and functional status were not satisfied as much as expected. After the third month of follow-up, her passive and active ROM of the shoulder joint was increased after application of manipulation under general anesthesia. In conclusion, because CRPS 1 remains one of the most difficult pain syndromes, early diagnosis and treatment are important to have adequate functional results from physical therapy. Manipulation under general anesthesia may be an additional effective treatment tool to obtain functional improvement in some patients diagnosed with CRPS 1.

공리적 설계 기반 선체 블록 레벨링 시스템 개발 (A Development of Ship Block Leveling System based on the Axiomatic Design)

  • 노재규;임남원;오정근
    • 해양환경안전학회지
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    • 제21권2호
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    • pp.207-214
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    • 2015
  • 본 연구에서는 공리적 설계 방법론에서 중요한 2가지 공리 중 독립공리를 시스템 개발에서 설계 기준으로 적용하였다. 기능 요구사항과 대응하는 설계 파라메터는 설계행렬을 구성하고 이를 이용하여 독립공리에 부합하는 설계 파라메터의 순서를 정한 후 블록 레벨링 시스템에서의 독립적 구성요소를 판별하였다. 이러한 공리적 설계의 결과로서 설계 순서에 맞는 블록 레벨링 시스템 구성을 도출하였다. 도출된 블록 레벨링 시스템 구성의 검증과 확인을 위해 블록 조립 현장에서 사용하고 있는 3차원 좌표 측정기인 토털 스테이션을 사용하여 실제 조립이 완료된 블록에 대하여 구현된 블록 레벨링 시스템을 적용하여 데이터를 비교하는 시험을 수행하였다. 토털 스테이션의 측정 데이터와 블록 레벨링 시스템의 수신 데이터를 비교하여 1 mm 이내의 정밀도로 블록 레벨링 시스템이 동작함을 검증하고 확인하였다.

Three-dimensional cone beam computed tomography analysis of temporomandibular joint response to the Twin-block functional appliance

  • Jiang, Yuan-yuan;Sun, Lian;Wang, Hua;Zhao, Chun-yang;Zhang, Wei-Bing
    • 대한치과교정학회지
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    • 제50권2호
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    • pp.86-97
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    • 2020
  • Objective: To propose a three-dimensional (3D) method for evaluating temporomandibular joint (TMJ) changes during Twin-block treatment. Methods: Seventeen patients with Class II division 1 malocclusion treated using Twin-block and nine untreated patients with a similar malocclusion were included in this research. We collected their cone beam computed tomography (CBCT) data from before and 8 months after treatment. Segmentations were constructed using ITK-SNAP. Condylar volume and superficial area were measured using 3D Slicer. The 3D landmarks were identified on CBCT images by using Dolphin software to assess the condylar positional relationship. 3D models of the mandible and glenoid fossa of the patients were constructed and registered via voxel-based superimposition using 3D Slicer. Thereafter, skeletal changes could be visualized using 3DMeshMetric in any direction of the superimposition on a color-coded map. All the superimpositions were measured using the same scale on the distance color-coded map, in which red color represents overgrowth and blue color represents resorption. Results: Significant differences were observed in condylar volume, superficial area, and condylar position in both groups after 8 months. Compared with the control group (CG), the Twin-block group exhibited more obvious condyle-fossa modifications and joint positional changes. Moreover, on the color-coded map, more obvious condyle-fossa modifications could be observed in the posterior and superior directions in the Twin-block group than in the CG. Conclusions: We successfully established a 3D method for measuring and evaluating TMJ changes caused by Twin-block treatment. The treatment produced a larger condylar size and caused condylar positional changes.