• Title/Summary/Keyword: Fixed length

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A Study on the Vibration Mode Measurement of Rectangular Plate with Two Parallel Sides Fixed by Electronic Speckle Pattern Interferometry (전자처리 스페클 간섭법에 의한 양단이 고정된 직사각형 평판의 진동모드 측정에 관 한 연구)

  • 김경석
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1996.03a
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    • pp.85-90
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    • 1996
  • In the word, there is varied types of vibration, and these affect the mechanical industry. In this paper is plates with two parallel sides fixed. Electronic speckle pattern interferometry (ESPI) is one of the optical nondestructive testing technique. By using the ESPI, vibration modes for excitation point, a/b(ratio of longuitudinal and lateral length), and kind of specimen are measured and compared qualitatively with theoritical analysis that Warburton proposed.

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CONTROLLING TRAFFIC LIGHTS AT A BOTTLENECK: THE OBJECTIVE FUNCTION AND ITS PROPERTIES

  • Grycho, E.;Moeschlin, O.
    • Journal of the Korean Mathematical Society
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    • v.35 no.3
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    • pp.727-740
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    • 1998
  • Controlling traffic lights at a bottleneck, in [5] a time of open passage is called optimal, if it minimizes the first moment of the asymptotic distribution of the queue length. The discussion of the first moment as function of the time of open passage is based on an analysis of the behavior of a fixed point when varying control parameters and delivers theoretical and computational aspects of the traffic problem.

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Design of the Fixed-Bed Catalytic Reactor for Phthalic Anhydride Production: Optimal Reactor Length and Radius Estimation (무수프탈산 생산을 위한 고정층 촉매 반응기 설계: 최적 촉매층 길이 및 반경 추정)

  • Yoon, Young-Sam;Koo, Eun Hwa;Park, Pan-Wook
    • Applied Chemistry for Engineering
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    • v.10 no.8
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    • pp.1200-1209
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    • 1999
  • Prediction model was composed by optimal parameter estimation from best fitting on reactant temperature profile, inlet and outlet temperature of coolant and yield of dual fixed-bed catalytic reactor(FBCR) which was measured in the industrial field. In order to design the FBCR which could obtain maximum conversion and yield, we investigated the effect of catalyst bed length and reactor radius changes. An uniform activity FBCR showed the best performance at z = 2.8 m of total catalysst bed length in case of reactor radius r = 0.01241 m and z =2.80 m(upper layer: 1.88 m, lower layer: 0.92 m) under reactor radius r = 0.01254 m for a dual activities FCBR. In case of reactor radius changes, the axial temperature profile and maximum radial temperature was rapidly risen for radius increase. The reactor radius decrease showed the opposite result.

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Parallel Approximate String Matching with k-Mismatches for Multiple Fixed-Length Patterns in DNA Sequences on Graphics Processing Units (GPU을 이용한 다중 고정 길이 패턴을 갖는 DNA 시퀀스에 대한 k-Mismatches에 의한 근사적 병열 스트링 매칭)

  • Ho, ThienLuan;Kim, HyunJin;Oh, SeungRohk
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.6
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    • pp.955-961
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    • 2017
  • In this paper, we propose a parallel approximate string matching algorithm with k-mismatches for multiple fixed-length patterns (PMASM) in DNA sequences. PMASM is developed from parallel single pattern approximate string matching algorithms to effectively calculate the Hamming distances for multiple patterns with a fixed-length. In the preprocessing phase of PMASM, all target patterns are binary encoded and stored into a look-up memory. With each input character from the input string, the Hamming distances between a substring and all patterns can be updated at the same time based on the binary encoding information in the look-up memory. Moreover, PMASM adopts graphics processing units (GPUs) to process the data computations in parallel. This paper presents three kinds of PMASM implementation methods in GPUs: thread PMASM, block-thread PMASM, and shared-mem PMASM methods. The shared-mem PMASM method gives an example to effectively make use of the GPU parallel capacity. Moreover, it also exploits special features of the CUDA (Compute Unified Device Architecture) memory structure to optimize the performance. In the experiments with DNA sequences, the proposed PMASM on GPU is 385, 77, and 64 times faster than the traditional naive algorithm, the shift-add algorithm and the single thread PMASM implementation on CPU. With the same NVIDIA GPU model, the performance of the proposed approach is enhanced up to 44% and 21%, compared with the naive, and the shift-add algorithms.

Effect of Polymerization Procedure on Thermal and Mechanical Properties of Polyether Based Thermoplastic Polyurethanes

  • Kim, Seong-Geun;Lee, Dai-Soo
    • Macromolecular Research
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    • v.10 no.6
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    • pp.365-368
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    • 2002
  • Thermoplastic polyurethanes (TPUs) with different hard segment length has been prepared from a fixed molar ratio of poly(tetramethylene ether glycol), 4,4'-diphenylmethane diisocyanate, and 1,4-butanediol by different polymerization procedures. Results reveal that the on-set temperature of endotherms ( $T_{cc}$ ) due to the crystallization of hard segments by cooling the TPUs from melt and the peak temperature of endotherms due to the melting of hard segments ( $T_{mh}$ ) by heating the TPUs increased and levelled off with increasing the hard segment length of TPUs. It has also been observed that soft segment glass transition temperature ( $T_{gs}$ ) of TPU decreased slightly with increasing the hard segment length, which explains less mixing of soft segments and hard segments. In tensile measurement of TPUs, strain hardening is observed with increasing the hard segment length, which is attributed to the strain induced crystallization of soft segments.

Estimation of Depth-Length Ratios with the Han-River Basin's Simultaneous Rainfall Data (한강유역 동시강우량 자료를 이용한 강우량-거리비의 산정)

  • 이원환;이길춘
    • Water for future
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    • v.20 no.1
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    • pp.55-61
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    • 1987
  • This Study is to estimate depth-length ratios by the frequency analysis of simultaneous rainfall data on fixed points in the Han -River basin. The depth-length ratios are based on examination of spatial and temporal correlation structures of the Han-River basin's rainfall. This Study reveals that the depth-length ratios are decreasing as the distance of the basin increases and that they are increasing as the duration of rainfall increases. This study also shows that the ratios tend to decrease as the return period increase. The results present general equations and characteristic equations of depth-length ratios, figures and characteristic parameter tables which explain the temporal and spatial structures of rainfall in the Han-River basin.

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A STUDY OF THE STRESS DISTRIBUTION ON THE SECOND ABUTMENT AND SUPPORTING TISSUES IN FIXED PARTIAL DENTURE USING THREE DIMENSIONAL FINITE ELEMENT ANALYSIS METHOD (고정성 가공의치에서 이차 지대치에 발생하는 응력의 삼차원 유한요소법적 분석)

  • Kim, Jeong-Hee;Jo, Kwang-Hun;Lee, Cheong-Hee
    • The Journal of Korean Academy of Prosthodontics
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    • v.38 no.5
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    • pp.675-694
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    • 2000
  • The purpose of this study was to investigate the displacement of and the stress distribution on the prosthesis, abutment, and its supporting tissues under functional load, and the effect of alteration in root length of 2nd abutment. The 3-dimensional finite element method was used and the finite element models were prepared in which the abutments of left mandibular 5 unit axed partial denture were canine, the 1st pre-molar and the 2nd molar, and the root lengths of canines were as follows. Model I : Root length of canine was 2mm longer than the 1st premolar Model II : Root length of canine was 2mm shorter than the 1st premolar Static compressive force of 300N was applied to connector between 2nd premolar & 1st molar, and then von Mises stress, displacement and reaction force were obtained. The results were as follows : 1. In fixed partial denture, prosthesis under load on pontic was rotated around mesio-distal long axis of it from longual side to buccal, and simultaneously bended in buccal and gingival direction with mesial end deformed in gingival direction and distolingual end in occlusal. 2. Clinical crowns of abutments were bended in the same directions with those in which prosthesis deforms. Due to that, roots of anterior abutments were twisted in counterclockwise with concentration of shear stress on distal or distobuccal sides of their cervices, and that of posterior was in clockwise with concentration of shear stress on mesiobuccal side of it in the same level with anterior abutments. 3. In case that root length of the 2nd abutment was longer than that of the 1st abutment, its displacement and reaction force which means the force tooth exerts on the surrounding periodontal tissues were smaller but shear stress on itself was larger than in the case root length of 2nd abutment was shorter.

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Numerical Study of Flow Characteristics in Elementary Paths of Velocity-Control Trim (속도 제어형 트림의 단위 요소 유로의 유동특성에 관한 수치적 연구)

  • Kim, Dae-Kwon;Sohn, Chae-Hoon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.3
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    • pp.245-253
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    • 2011
  • We investigate the flow characteristics of elementary-flow paths with $90^{\circ}$ bends; a velocity-control trim consists of such paths. For geometric similarity, the width and length of each path are selected, and the number of bends is 0, 4, or 8. The flow tests are conducted with the same flow-path elements. The numerical results are in good agreement with the experimental data. In elements without bends, the volume flow rate decreases with the length of the flow path, with a constant pressure drop between the inlet and the outlet. However, in flow paths with $90^{\circ}$ bends, it increases and then decreases with the length of the flow path. For a fixed number of $90^{\circ}$ bends, better pressure-drop characteristics are observed as the length of the flow path increases. For a fixed flow-path length, a flow-path element with more bends has a smoother pressure drop along the path.

Morphological Diversity of Various Divisions of the Rabbit Colon (집토끼 결장 각 부위의 구조에 대한 광학 및 주사전자현미경적 관찰)

  • Chung, J.W.;Chun, M.H.;Oh, S.J.;Kwun, H.S.
    • Applied Microscopy
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    • v.14 no.2
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    • pp.81-93
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    • 1984
  • Structural differences in various divisions of the rabbit colon were investigated using light and scanning electron microscopy. For light microscopic study, various Portions of the colon from seven rabbits (2.5 kg body weight) were fixed in 10% neutral buffered formalin, and paraffin sections were stained with hematoxylin-eosin. Tissues for scanning electron microscopy were fixed in 1% glutaraldehyde-1.5% paraformaldehyde and postfixed in 1% $OsO_4$, dehydrated to 100% alcohol, transfered to isoamilacetate and dried by the critical point method. Subsequently, specimens were coated with gold and viewed with a JSM-35C scanning electron microscope. The colon displays a morphological diversity along its proximo-distal axis. Five regions can be discerned based on the macroscopic and microscopic characteristics. 1) The first segment immediately distal to the cecocolical junction possessing three teniae is approximately 5 cm ($4{\sim}6cm$) in length, and displays irregular folds of the mucosa oriented transversely similar to those of the cecum. 2) The second segment possessing three teniae is about 7 cm ($5{\sim}8cm$) in length, and is characterized by the papilla-like protrusions on the mucosal surface. 3) The third segment, possessing a single tenia is about 16 cm ($12{\sim}20cm$) in length, and also displays the papilla-like protrusions similar to the aforegoing segment. 4) Fusus coli, approximately 4 cm ($3{\sim}5cm$) in length, is free of teniae and exhibits longitudinal folds on the mucosal surface. These four portions together constitute the proximal colon. 5) The distal colon reaches a length of about 58 cm ($53{\sim}55cm$) and shows a pattern of surface irregularities with minor ridges on the mucosal folds.

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