• Title/Summary/Keyword: intermediate

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다양한 머리 형상을 갖는 체결구의 냉간 단조 자동 공정 설계 시스템 (Automatic Process Design System for Cold Forging of Fasteners with Various Head Geometries)

  • 김홍석;임용택
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1994년도 추계학술대회 논문집
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    • pp.141-148
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    • 1994
  • In order to improve the productivity of cold forging at low production cost, an integrated system's approach is necessary in handling the material preparation and the optimum process design, considering the forming machines, tooling, and operation including quality control. As the first step toward this approach, an expert system for multi-stage cold forging process design for fasteners with various head geometries is developed using Prolog language on IBM 486 PC. For effective representation of the complex part geometries, the system uses the multiple element input, and the forward inference scheme in determination of the initial billet size and intermediate forging steps. In order to determine intermediate steps, the basic empirical rules for extrusion, heading, and trimming were applied. The required forming loads and global strain distributions at each forging step were calculated and displayed on the PC monitor. The designed process sequence drawing can be obtained by AutoCAD. The developed system will be useful in reducing trial and error of design engineers in determining the diameter and height of the initial cylindrical billet from the final product geometry and the intermediate necessary sequences.

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선형 배열 롤 셋 공정에서의 중간 형상 설계 (Design of intermediate shape in line array roll set (LARS) process)

  • 심도식;양동열;정성욱;한명수
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 춘계학술대회 논문집
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    • pp.215-219
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    • 2009
  • For the effective manufacture of doubly curved metal plates, a line array roll set (LARS) process is proposed. The suggested process utilizes a pair of upper and lower symmetric roll assemblies. In the process, the initial plate is progressed into the final shape in a stepwise or pathwise manner according to the basic principle of the incremental forming process. In this work, the intermediate shape which is closest to a final shape is proposed to fabricate the desired shape effectively in design of forming schedule. The intermediate shape has homogeneous curvature in a longitudinal and transverse direction so that it can be fabricated easily without complicated controls of rolls in the roll set. The method of approximation using genetic algorithm is proposed and applied to some actual ship hulls to evaluate the efficiency of the algorithm.

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영남지방(嶺南地方) 축우(畜牛) 간질충(肝蛭蟲)의 감염율(感染率) 및 간질충(肝蛭蟲)의 형태(形態)에 관(關)하여 (Studies on the infectious. rate and morphology of Fasciola species of Korean native cattle in Young Nam district)

  • 김화식;박준형
    • 대한수의학회지
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    • 제7권2호
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    • pp.42-45
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    • 1967
  • From April to May 1967 3,275 Korean native cattle slaughtered at Taegu public slaughter house were investigated for infection rate of faciola and 222 adult fasciola species taken from the bile duct, of the patients were examined for morphological study. The results were as follows: 1. Among 3,275 Cattle 1,099 Cattle (32.5%) were infected with fasciola species. 2. Seasonal changes of infection rate were 34.7%(Winter). 33.2%(Spring), 30.9%(fall) and 29.1%(Summer). 3. Three different species(large, small and intermediate type) of fasciola were detected from the patients. These large, small and intermediate types were identified morphologically with fasciola gigantica, fasciola hepatica and fasciold indica respectivelly. Distribution of these three kind, were 52.4%(intermediate type), 28.4%(Small type) and 19.0%(large type).

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Antimicrobial Properties of Wheat Gluten-Chitosan Composite Film in Intermediate-Moisture Food Systems

  • Park, Sang-Kyu;Bae, Dong-Ho
    • Food Science and Biotechnology
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    • 제15권1호
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    • pp.133-137
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    • 2006
  • Wheat gluten-chitosan composite film (WGCCF) can prevent moisture migration and enhance the antimicrobial properties of gluten in intermediate-moisture foods like sandwiches. To mimic the structure of actual sandwich-type products we developed multi-layer food models, where moisture content and water activity differ. Water activity gradients direct moisture migration and therefore determine product characteristics and product stability. A 10% wheat gluten film-forming solution was mixed with chitosan film-forming solution (0-3%, w/w) and evaporated to generate WGCCF. Addition of 3% chitosan enhanced the mechanical properties of the film composite, lowered its water vapor permeability, and improved its ability to protect against both, Streptococcus faecalis and Escherichia coli, in a 24 hr sandwich test (reduction of 1.3 and 2.7 log cycles, respectively, compared to controls). Best barrier and antimicrobial performance was found for 3% chitosan WGCCF at pH 5.1. Film of this type may find application as barrier film for intermediate-moisture foods.

주산기 태아 흰쥐의 뇌하수체 전엽에서 분비되는 ACTH의 다형현상 (Polymorphism of ACTH Released by Adenohypophysis of Fetal Rat during Perinatal Period)

  • 김희승
    • The Korean Journal of Physiology
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    • 제19권2호
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    • pp.215-225
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    • 1985
  • 흰쥐의 태아에서 ACTH의 분비양상을 알아보기 위하여, 태아의 제태일수에 따라 혈장 및 뇌하수체 전엽에서 여러 분자형태의 ACTH를 방사면역측정법으로 측정하였다. 태아의 혈장 ACTH농도는 제태 19일에서 가장 높았으며 그후 계속 감소하여 출생후 1주에서 가장 낮은 값을 보였다. 출생 1주후부터 ACTH농도는 다시 증가하기 시작하여 출생후 21일에서는 거의 성체의 값에 도달하였다. 측정된 ACTH는 chromatogram상에서 항상 3가지 peak가 나타났다. 즉 'big'형 ('big' ACTH, $MW\approx44,000$), 'intermediate'형 ('intermediate' ACTH, $MW\approx13,000$)및 'little'형 ('little' ACTH, $MW\approx4,500$)으로 구분되었다. 임신말기 (제태기간 17일에서 21일 사이)에서 태아 혈장의 ACTH는 'little'형의 비율이 증가한 반면 'big'형의 비율은 감소하였다. 그러나 뇌하수체 전엽에서 분비된 ACTH는 3가지 형이 같은 비율이었다. 뇌하수체 전엽에서 분리한 'big'형의 ACTH를 시침관내에서 trypsin을 처리한 결과 'intermediate'형과 little'형이 출현하였다. 이 결과로 미루어 태아 흰쥐의 뇌하수체에서 분비된 ACTH가 순환도증 다른 형으로 전환될 수 있음이 시사된다.

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산화막중간층에 의한 수직자기기록층의 입자크기 미세화 (Fine Granulation of Recording Layer in Perpendicular Magnetic Recording Media Using Oxide-interlayer)

  • 김경환;공석현
    • 한국표면공학회지
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    • 제37권4호
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    • pp.196-199
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    • 2004
  • Seedlayers with low surface energy which increases the density of nucleation sites in the initial growth region of the recording layer deposited on them was studied to reduce grain size in recording layer. The seedlayer with low surface energy was so effective to attain finer grain in magnetic upper-layers. The Ni-Fe-O intermediate layer with low surface energy was found to be effective in reduction of grain size as well as magnetic cluster size of Co-Cr-Ta-Pt recording layer. Furthermore, the reduction of grain size in Co-Cr-Ta-Pt recording layer on Ni-Fe-O intermediate layer with low surface energy led to decrease the noise level in the high recording density region.

Flexural strength of roller compacted concrete pavements reinforced with glass-roved textiles

  • Madhkhan, Morteza;Nowroozi, Saeid;Torki, Mohammad E.
    • Structural Engineering and Mechanics
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    • 제55권1호
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    • pp.137-160
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    • 2015
  • The one-way (two-way) flexural strength of RCC prisms (circular slabs) reinforced with glass fiber textiles is addressed. To this end, alkaline-resistant glass fiber textiles with three surface weights were used in the composite, the matrix concrete was designed with zero/nonzero slump, and the textiles were used with/without an intermediate layer provided by epoxy resin and sand mortar. Prisms were tested under a four-point loading apparatus and circular slabs were placed on simple supports under a central load. Effects of the amount and geometry of reinforcement, matrix workability, and the intermediate layer on the ultimate load and deflection were investigated. Results revealed that, with a specific reinforcement amount, there is an optimum textile tex for each case, depending on the matrix mix design and the presence of intermediate layer. Similar results were obtained in one-way and two-way bending tests.

Thermal buckling load optimization of laminated plates with different intermediate line supports

  • Topal, Umut
    • Steel and Composite Structures
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    • 제13권3호
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    • pp.207-223
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    • 2012
  • This paper deals with critical thermal buckling load optimization of symmetrically laminated four layered angle-ply plates with one or two different intermediate line supports. The design objective is the maximization of the critical thermal buckling load and a design variable is the fibre orientation in the layers. The first order shear deformation theory and nine-node isoparametric finite element model are used for the finite element solution of the laminates. The modified feasible direction (MFD) method is used for the optimization routine. For this purpose, a program based on FORTRAN is used. Finally, the numerical analysis is carried out to investigate the effects of location of the internal line supports, plate aspect ratios and boundary conditions on the optimal designs and the results are compared.

Antitumorigenic Effects of Tannin From Persimmon Leaves on Sarcoma 180-induced Tumor in Mice

  • Moon, Sung-Chai;Park, Kyong-Hee;Rhew, Tae-Hyong;Park, Kun-Young;Kim, Byeong-Gee
    • Preventive Nutrition and Food Science
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    • 제3권1호
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    • pp.92-97
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    • 1998
  • The changes of morphology and protein pattern of sarcoma 180 cells treated with or without trannins extracted from persimmon leaves were evaluated by light microscopy, electrophoresis and Western blotting. The sarcoma 180 cells treated with tannins increased the amount of proteins which presumably were intermediate filament cytokeratins detected by electrophoresis and Western blot. Tannins was indirectly cytotoxic to the sarcoma 180 cells and increased the intermediate filament protein level in the cells.

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최소비용문제의 퇴화 정점 최적해에 대한 감도분석 (Sensitivity Analysis on the Degenerate Tree Solution of the Minimum Cost Flow Problem)

  • 정호연;박순달
    • 산업공학
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    • 제7권3호
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    • pp.193-199
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    • 1994
  • The purpose of this paper is to develop a method of the sensitivity analysis that can be applicable to a degenerate tree solution of the minimum cost flow problem. First, we introduce two types of sensitivity analysis. A sensitivity analysis of Type 1 is the well known method applicable to a spanning tree solution. However, this method have some difficulties in case of being applied to a degenerate tree solution. So we propose a sensitivity analysis of Type 2 that keeps solutions of upper bounds remaining at upper bounds, those of lower bounds at lower bounds, and those of intermediate values at intermediate values. For the cost coefficient, we present a method that the sensitivity analysis of Type 2 is solved by using the method of a sensitivity analysis of Type 1. Besides we also show that the results of sensitivity analysis of Type 2 are union set of those of Type 1 sensitivity analysis. For the right-hand side constant or the capacity, we present a simple method for the sensitivity analysis of Type 2 which uses arcs with intermediate values.

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