• Title/Summary/Keyword: Model compound

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Cutter Interference Avoidance in NC Machining of Compound Surfaces (복합곡면 NC 가공에서의 공구간섭 방지)

  • Jun, Cha-Soo
    • Journal of Korean Institute of Industrial Engineers
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    • v.19 no.3
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    • pp.139-154
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    • 1993
  • Cutter Interference(or part surface gouging) is one of the most critical problems in NC machining of sculptured surfaces. Presented in this paper is and algorithmic procedure that converts CC data obtained from a compound surface(several surfaces without topological relationship) into interference-free CL data. The interference handling procedure consists of following steps: (1) Z-map model is constructed from input surfaces. (2) Interference sources are detected using local properties of the sources. (3) Interference regions are completely identified based on global tests for neighboring CC points of the interference sources (4) Cutter paths are reconstructed after removing the CC data in interference regions, while avoiding any new interferences.

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Finite Element Analysis of Cylinder Head/Block Compound (엔진 실린더 헤드/블록의 유한 요소 해석)

  • Kim, Beom-Keun;Chang, Hoon
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.3
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    • pp.28-38
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    • 2003
  • Finite element analysis of cylinder heat/block compound under assembly, thermal and firing condition were performed. FE model including two cylinders with gasket, head bolts, liners and valve seats was used. FE modeling method and boundary conditions were introduced. Stress distribution and deformation of cylinder head and block under each loading condition were presented. Gasket pressure distribution and bore distortion level were predicted. Measured data of bore distortion was compared with the analysis results. The analysis result showed similar trends with the experimental data. High cycle fatigue analysis on the basis of this result has been performed in order to find the critical areas of the engine assembly.

The Ameliorative Effect of Adenophorae Radix on Atopic Dermatitis in vivo and in vitro

  • Jung, Ji-Wook;Kim, Su-Jin
    • Biomedical Science Letters
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    • v.20 no.3
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    • pp.117-123
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    • 2014
  • Adenophorae Radix (AR) has been used as a traditional medicine for various diseases. However, the regulatory effects of AR in atopic dermatitis are not yet understood. This study attempted to determine the pharmacological effects of AR and its constituent on both compound 48/80 or histamine-induced scratching behaviors and 2, 4-dinitrochlrobenzene (DNCB)-induced atopic dermatitis in mice. The findings of this study demonstrated that AR reduced compound 48/80 or histamine-induced scratching behaviors in mice. Treatment of AR attenuated the AD symptoms such as eczematous, erythema and dryness and serum IgE and IL-6 levels in AD model. Additionally, AR inhibited the TNF-${\alpha}$-induced the Nuclear factor-${\kappa}B$ activation in HaCaT cells. Collectively, the findings of this study provide us with novel insights into the pharmacological actions of AR as a potential molecule for therapeutic agent against atopic dermatitis.

Antihypertensive Activities of Diterpenoid (16,17-dihydroxy-16-${\beta}-(-)$-kaurane-19-oic acid) in Siegesbeckiae pubescens Against Okamoto-Spontaneously Hypertensive Rats (희첨 성분중 디터핀 물질이 오까모토 고혈압 모델 쥐에 미치는 혈압 강하작용)

  • Kim, Jae-Hoon;Yu, Jae-Chun;Chang, Il-Moo;Lee, Jong-Heun;Kim, Joong-Soo
    • Korean Journal of Pharmacognosy
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    • v.11 no.2
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    • pp.61-65
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    • 1980
  • As a folkloric medicine, Siegesbeckia pubescens has been used for treatment of brain stroke and hypertension. Diterpene compound, 16,17-dihydroxy 16-${\beta}-(-)$ kaurane-19-oic acid, was isolated from the plant. Its potential antihypertensive activity was evaluated againstan animal model of hypertension, Okamoto-SHR. When diterpene compound with dose of 50mg/kg/day was orally administered, it exhibited mild antihypertensive activity comparable with propranolol administration dose of 75mg/kg/day.

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A Study on the Tool Interference Detection and Tool Path Correction in Compound Surface Machining (복합곡면 가공시 공구간섭의 탐지와 공구경로 수정에 관한 연구)

  • 조명우
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.8 no.6
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    • pp.105-112
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    • 1999
  • In this paper we deal with tool interference problem in the case of compound surface machining. A new tool interference detection and correction method based on the envelope of the tool path is suggested to identify and correct the tool interference - not only within the local path of tool movement, but also outside of the tool path. Therefore, the developed strategy can be used to check the possible interference in any region of the surface. In order to analyze quantitatively the milled surface error produced by the tool interference, improved surface prediction model is also suggested in cutting process by general cutters. The effectiveness of the proposed method is demonstrated through simulation study.

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Spin Exchange Coupling in Dimethoxo-Bridged Dichromium(III) Complexes: A Density Functional Theory Study

  • Kang, Dae-Bok
    • Bulletin of the Korean Chemical Society
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    • v.29 no.5
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    • pp.963-968
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    • 2008
  • For the [$Cr_2(H_2tmp)_2Cl_4$] compound, simplified models with two bridging methoxo ligands have been studied. The influence of the bridging Cr-O-Cr bond angles on the exchange coupling between metal atoms in the model compound has been analyzed by means of density functional calculations with the broken-symmetry approach. Coupling constant calculated for the full structure is in good agreement with the experimentally reported value, confirming the validity of the computational strategy used in this work to predict the exchange coupling in a family of related dinuclear Cr(III) compounds. The calculations indicate a good correlation between the calculated coupling constant and the sum of the squared energy gap of three pairs of metal $t_{2g}$ OMSOs with a limited variation of the Cr-O-Cr angle. The spin density distribution and the mechanism of magnetic coupling interactions are discussed.

Order Based Performance Evaluation of a CONWIP System with Compound Poisson Demands (복합포아송 수요를 가지는 CONWIP 시스템에서 고객집단의 성능평가)

  • Park Chan-U;Lee Hyo-Seong
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2004.10a
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    • pp.8-12
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    • 2004
  • In this study we consider a CONWIP system in which the processing times at each station follow a Coxian distribution and the demands for the finished products arrive according to a compound Poisson process. The demands that are not satisfied are backordered according to the number of demands that exist at their arrival instants. For this system we develop an approximation method to calculate order based performance measures such as the mean time of fulfilling a customer order and the mean number o: customer orders. For the analysis of the proposed CONWIP system, we model the CONWIP system as a closed queueing network with a synchronization station and analyze the closed queueing network using a product form approximation method. Numerical tests show that the approximation method provides fairly good estimation of the performance measures of interest.

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Action of enzyme food, Green Life Enzyme on systemic and local anaphylaxis

  • Moon, Phil-Dong;Na, Ho-Jeong;Kim, Hyung-Min
    • Advances in Traditional Medicine
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    • v.3 no.1
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    • pp.46-50
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    • 2003
  • We studied the inhibitory effect of Green Life Enzyme (GLE) on compound 48/80-induced anaphylactic response in a murine model. GLE inhibited compound 48/80-induced systemic anaphylactic shock at the dose of 10 g/kg by 87.5%. When GLE was given as pre-treatment at concentrations ranging from 0.01 to 1.0 g/kg, it inhibited passive cutaneous anaphylaxis activated by anti-dinitrophenyl (DNP) IgE. In addition, GLE (0.1 mg/ml) inhibited anti-DNP IgE-induced tumor necrosis $factor-{\alpha}$ production from mast cells by 69% compared to saline value. These results indicate that GLE may possess anti-anaphylactic and anti-inflammatory activity.

Bifunctional Group Participated Nitrile Group Hydrolyzing Enzyme Model Systems: Hydrolysis of the Nitrile Group of $\alpha$-Aminophenylacetonitrile to Phenylglycineamide and Phenylglycine by Various thiol Compounds

  • Lee, Young-Bok;Goo, Yang-Mo;Lee, Jae-Keun
    • Archives of Pharmacal Research
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    • v.11 no.4
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    • pp.285-291
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    • 1988
  • 2-mercaptoethanol, thioglycolic acid, glutathione, 3-mercapto-1, 2-propanediol and 3-mercapto-2-butanol showed catalytic activities on the hydrolysis of $\alpha$-amino-phenylacetonitrile to phenylglycineamide at the rate of 12.19 $\times$ $10^{-2}$, 8.03 $\times$ $10^[-2}$, 6.83 $\times$ $10^{-2}$, 8.60 $\times$ $10^{-2}$ and 6.04 $\times$ $10^{-2}$ mM $min^{-1}$, respectively. hte hydrolysis rate was faster in buffer than in water. The hydrolysis of the nitrile compound to phenylglycine was limited.

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A New Synthetic Route to Poly(benzimidazole) and the Related Model Reactions to Imidazoline and Benzimidazole

  • Shin, G. I.;Kim, Ji Heung
    • Bulletin of the Korean Chemical Society
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    • v.17 no.1
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    • pp.29-33
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    • 1996
  • Mono-, or di-substituted chlorodicyanovinyl benzene compound was reacted with an excess amount of ethylenediamine to give corresponding imidazoline product with high reaction yield. This reaction occurs by stable imidazoline ring-forming process through nucleophilic attack of terminal amine on the enaminonitrile adduct, the reaction intermediate, toward electropositive enamine carbon, which is accompanied by the release of neutral malononitrile moiety. The similar reaction with 1,2-phenylenediamine produced stable enaminonitrile-amine adduct at lower temperature which could be cyclized intramolecularly to thermally stable benzimidazole at elevated temperature in solution or in solid state. From the difunctional compound of both reactants, poly(enaminonitrile-amine) could be prepared as a new soluble precursor polymer for well-known polybenzimidazole (PBI). The thermal cyclization reaction accompanying the release of malononitrile molecules was studied using thermalanalysis and infrared spectroscopy.