• 제목/요약/키워드: Rate-Determining

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적층복합재의 자유단 박리에 대한 모드별 스트레인 에너지해방률의 간이계산법 (A Simplified Method for Determining Modal Strain Energy Release Rate of Free-Edge Delaminations in Laminated Composite)

  • 김택현;오택열;김인권
    • 대한기계학회논문집A
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    • 제21권3호
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    • pp.423-429
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    • 1997
  • A simplified method for determining the mode components of the strain energy release rate of free-edge delaminations in laminated composite is proposed. The interlaminar stresses are evaluated as an interface moment and interface shear forces that are obtained from the equilibrium equations at the interface between the adjacent layers. Deformation of an edge-delaminated laminate is calculated by using a generalized quasi-three dimensional classical laminated plate theory developed by the authors. The analysis provides closed-form expression for the three components of the strain energy release rate. Comparison of results with a finite element solution using the virtual crack closure technique shows good agreement. In the present study, laminated composite with stacking sequences of [30/-30/90]$_{s}$ were examined. The simple nature of the method makes it suitable for primary design analysis for the delaminations of laminated composite.e.

특허가치평가를 위한 합리적 로열티율 산정 방안 - 손해액산정모형을 중심으로 (Some Methods Determining Reasonable Royalty Rates for Patent Valuation - An Infringement Damages Model)

  • 양동홍;김성철;강근석
    • 기술혁신학회지
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    • 제15권3호
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    • pp.700-721
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    • 2012
  • 본 연구는 특허권의 경제적 가치를 산정하는데 있어서, 합리적인 로열티율을 구하기 위한 방법에 관한 것이다. 특허권 자체의 합리적인 로열티율을 산정하기 위해, 기존의 25% 룰의 장단점과 최근 동향을 살펴보았으며, 내쉬 협상 방정식의 게임이론을 이용한 산정방법과 재무분석을 통한 투자수익률 방법을 적용하여 합리적인 로열티율을 산출하였다. 손해액 산정 모형에서는 최근의 미국 특허침해 손해액 산정 시 실시료 상당액으로 판결한 미국 법원의 판례를 이용하여 당해 침해 관련 특허를 분석하고, 각 특허의 서지(書誌)사항 항목에서 특허지표를 추출해서 이를 회귀분석을 이용하여 개별 특허권의 합리적인 로열티율을 산정하는 모형을 제시하고 미국의 판례자료를 이용한 분석결과를 제시하였다.

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Kinetics and Mechanism of Azidolysis of Y-Substituted Phenyl Benzoates

  • Um, Ik-Hwan;Kim, Eun-Hee;Han, Hyun-Joo
    • Bulletin of the Korean Chemical Society
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    • 제29권3호
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    • pp.580-584
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    • 2008
  • Second-order rate constants (kN) have been measured spectrophotometrically for reactions of Y-substituted phenyl benzoates (1a-h) with azide ion (N3) in 80 mol % H2O/20 mol % DMSO at 25.0 0.1 oC. The Brnsted-type plot for the azidolysis exhibits a downward curvature, i.e., the slope (b lg) changes from 0.97 to 0.20 as the basicity of the leaving group decreases. The pKao (defined as the pKa at the center of the Brnsted curvature) is 4.8, which is practically identical to the pKa of the conjugate acid of N3 ion (4.73). Hammett plots correlated with s o and s constants exhibit highly scattered points for the azidolysis. On the contrary, the corresponding Yukawa-Tsuno plot results in an excellent linear correlation with r = 2.45 and r = 0.40, indicating that the leaving group departs in the rate-determining step. The curved Brnsted-type plot has been interpreted as a change in the rate-determining step in a stepwise mechanism. The microscopic rate constants (k1 and k2/k1 ratio) have been calculated for the azidolysis and found to be consistent with the proposed mechanism.

Aminolysis of Y-Substituted Phenyl 2-Thiophenecarboxylates and 2-Furoates: Effect of Modification of Nonleaving Group from 2-Furoyl to 2-Thiophenecarbonyl on Reactivity and Mechanism

  • Um, Ik-Hwan;Min, Se-Won
    • Bulletin of the Korean Chemical Society
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    • 제29권3호
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    • pp.585-589
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    • 2008
  • Second-order rate constants (kN) have been measured for reactions of Y-substituted phenyl 2-thiophenecarboxylates (6a-h) with morpholine and piperidine in 80 mol % H2O/20 mol % DMSO at 25.0 0.1 oC. The Brnsted-type plot for the reactions of 6a-h with morpholine is linear with b lg = 1.29, indicating that the reactions proceed through a tetrahedral zwitterionic intermediate (T?). On the other hand, the Brnsted-type plot for the reactions of 6a-h with piperidine exhibits a downward curvature, implying that a change in the rate-determining step occurs on changing the substituent Y in the leaving group. Dissection of kN into microscopic rate constants (i.e., k1 and k2/k1 ratio) has revealed that k1 is smaller for the reactions of 6a-h than for those of Y-substituted phenyl 2-furoates (5a-h), while the k2/k1 ratio is almost the same for the reactions of 5a-h and 6a-h. It is also reported that modification of the nonleaving group from the furoyl (5a-h) to the thiophenecarbonyl (6a-h) does not influence pKao (defined as the pKa at the center of the Brnsted curvature) as well as the k2/k1 ratio.

Aminolyses of 2,4-Dinitrophenyl 2-Furoate and Benzoate: Effect of Nonleaving Group on Reactivity and Mechanism

  • Um, Ik-Hwan;Chun, Sun-Mee;Akhtar, Kalsoom
    • Bulletin of the Korean Chemical Society
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    • 제28권2호
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    • pp.220-224
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    • 2007
  • Second-order rate constants (kN) have been determined spectrophotometrically for reactions of 2,4-dintrophenyl 2-furoate (2) with a series of alicyclic secondary amines in 80 mol % H2O/20 mol % dimethyl sulfoxide (DMSO) at 25.0 oC. The furoate 2 is more reactive than 2,4-dintrophenyl benzoate (1) toward all the amines studied. The higher acidity of 2-furoic acid (pKa = 3.16) compared with benzoic acid (pKa = 4.20) has been suggested to be responsible for the reactivity order, at least in part. The Brønsted-type plots for the reactions of 1 and 2 are curved downwardly, indicating that the aminolyses of both 1 and 2 proceed through a zwitterionic tetrahedral intermediate (T±) with a change in the rate-determining step on changing the amine basicity. Dissection of the kN values into their microscopic rate constants has revealed that the pKao and k2/k-1 ratios for the reactions of 1 and 2 are identical, indicating that the nature of the nonleaving group (i.e., benzoyl and 2-furoyl) does not affect the reaction mechanism. The k1 values have been found to be larger for the reactions of 2 than for those of 1, which is fully responsible for the fact that the former is more reactive than the latter.

도시부 신호교차로의 기본용량 및 기하구조 보정계수 (Ideal Saturation Flow Rate and Geometric Adjustment Factors at Urban Signalized Intersection)

  • 오영태;심대영
    • 대한교통학회지
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    • 제10권2호
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    • pp.5-24
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    • 1992
  • This research presets the method of determining basic capacity of signalized intersection using the concept of ideal saturation flow rate. Vehicle discharge rates during green time were collected and studied as part of the preparation of Korean Highway Capacity Manual. From the result of this study the ideal saturation flow rate and saturation queue position were determined. In addition, based on the ideal saturation flow rate two geometric adjustment factors(lane width and grade adjustment factors) were studied. The results were presented in this paper.

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오프셋 인쇄 잉크의 유화 속도에 영향을 미치는 인자에 관한 연구 (A Study on the Factors Determining the Emulsion Velocity of Off-Set Ink)

  • 김인겸;김성빈;김종래
    • 한국인쇄학회지
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    • 제19권1호
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    • pp.28-41
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    • 2001
  • Rheological properties of ink and Ink-Water balance are the important factors in lithographic printing. Laboratory test method which determines the emulsification rate of dampening solution and ink has been described. The emulsification theory and laboratory test method deduced from Surland and it has become a useful tool for the industry. The effects of pH value and surface tension of dampening solution on the emulsification rate has been tested by many researcher. In this paper we focused on the factors which influence in the emulsification such as pH and surface tension of dampening solution and emulsifying temperature. To study on the factors determining the emulsion velocity, we have measured water pickup and calculated emulsion velocity constant 'k' and activation energy.

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신경망을 이용한 방전 조건의 적응적 결정 방법 (Adaptive Identification Method of EDM Parameters Using Neural Network)

  • 이건범;주상윤;왕지남
    • 한국정밀공학회지
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    • 제15권5호
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    • pp.43-49
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    • 1998
  • Adaptive neural network approach is presented for determining Electrical Discharge Machining (EDM) parameters. Electrical Discharge Machining has been widely used with its capability of machining hard metals and tough shapes. In the past few years, EDM has been established in tool-room and large-scale production. However. in spite of it's wide application, an universal selection method of EDM parameters has not been established yet. No attempt has been tried before to suggest a logical method in determining essential machine parameters considering the machining rate and resulting surface roughness integrity. The paper presents a method, which is focusing on determining appropriate machining parameters. Depending on the electrode wear and surface roughness, an adaptive neural network is designed for providing suitable machining guideline.

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외상 환자의 중증도 판단과 예후 예측을 위한 개별 인자들의 유용성 평가 (Evaluation the Usefulness of Individual factors for Determining the Severity and Predicting Prognosis of Trauma Victims)

  • 김성윤;소병학;김형민;정원중;차경만;최승필
    • Journal of Trauma and Injury
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    • 제28권3호
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    • pp.134-143
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    • 2015
  • Purpose: Many patients are injured by trauma. And some of them expire due to severity of trauma. Various scoring systems have been introduced in grading severity and predicting mortality of trauma patients. This study is to evaluation the usefulness of factors for determining the severity and predicting the prognosis of the trauma victims. Methods: Data on the patients who visited our Emergency departments from January 2010 to December 2011 were retrospectively reviewed using electronic medical records. The patients were activated severe trauma team calling system. The patients were categorized as survivors and non-survivors. Univariated associations were calculated, and a multiple logistic regression analysis was used to determine variables associated with hospital mortality. Results: Two hundred sixty two(262) patients were enrolled, and the mortality rate was 25.6%. By multivariate analysis, lower respiration rate, lower Glasgow Coma Score, higher International Normalized Ratio and emergency transfusion within 6 hours were expected as severity and prognosis predict factors (each of odds ratio were 24.907, 14.282, 2.667 and 16.144). Conclusion: As predict factors, respiration rate, Glasgow Coma Score, International Normalized Ratio and emergency transfusion, are useful determining the severity and predicting prognosis of trauma victims.

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