• 동력기계공학회지
• /
• 제15권6호
• /
• pp.95-100
• /
• 2011

In this study, an evaluation equation of energy efficiency of pneumatic driving apparatus is proposed. The evaluation equation is derived from state equation and energy equation of air in a control volume, and, the equation of motion of a moving part of a pneumatic cylinder. As a result, distribution of consumption energy and energy efficiency of pneumatic driving apparatus can be analyzed quantitatively. The effectiveness of the proposed method is proved by a pneumatic cylinder driving apparatus using a meter-out driving method.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2000년도 추계학술대회논문집
• /
• pp.25.2-31
• /
• 2000

Recently, Fuzzy theory has been applied in evaluation problem. Fuzzy evaluation based on Fuzzy theory can accommodate fuzziness of judgement with people through introducing Fuzzy measure. Representative Fuzzy evaluation is Fuzzy Integral using Fuzzy measure. Definite methodology using Fuzzy Integral HFI(Hierarchical Fuzzy Integrals), HFEA(Hierarchical Fuzzy Evaluation Algorithm), HFP(Hierarchical Fuzzy Process), etc. In this paper, we deal with problem identifying evaluation value using Fuzzy Relation Equation at these Fuzzy evaluation. We verify relation between Input data and Output data through @-operation and apply this to HFP. And that we verify evaluation value which objects of evaluation are able to possess.

• 한국철도학회논문집
• /
• 제9권4호
• /
• pp.432-440
• /
• 2006

Prior to the service evaluation, many kinds of its attributes must be identified on the basis of rational decision owing to complexity and ambiguity inherent in logistics service. there are so many evaluation methods but they are not applicable to logistics service the have property of non-additivity and overlapped attributes. Therefore, probability measure can not used to evaluate logistics service but Fuzzy Measure is required. And the method should be easy to calculate it Recently Fuzzy theory has been applied in Various evaluation problem. Fuzzy evaluation based on Fuzzy theory can accommodate fuzziness in judgement with people through introducing Fuzzy Measure. In this paper, Hierarchical Fuzzy Process is applied to evaluate level of logistics service in Korail and the biggest six logistics companies in the korea which is called 3PL Company. Also Fuzzy Relation Equation which is problem identifying evaluation value at these fuzzy evaluation is applied to verify relation between Input and Output data through @-operation. Therefore, we apply this Fuzzy Relation Equation to Hierarchical Fuzzy Process and verify evaluation value which objects of evaluation are able to possess.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
• /
• pp.253-258
• /
• 2002

An evaluation equation of the minimum shear reinforcement content for reinforced concrete beams was theoretically proposed. The proposed equation takes into account the effects of compressive strength of concrete, longitudinal reinforcement content and shear span ratio. The proposed equation was compared with the current ACI 318-99 and CSA A23.3-94 codes.

• 한국소음진동공학회논문집
• /
• 제12권8호
• /
• pp.626-631
• /
• 2002

A modified equation for the evaluation of discomfort of a seated human body exposed to differential vibration at the seat and the floor was proposed in this paper. Through the review and analysis of the preceding studies, effect of phase difference between the seat and the floor vibration on discomfort were quantitatively identified. The phase effect was shown to be governed by not only phase difference between the two vibrations but both their frequency and the magnitude, which means the present equation for the evaluation of perceptual amount of vibration provided by ISO 2631-1 should be modified. The proposed equation was developed such that the correction function was multiplied to the present equation. The correction function consisted of three parts, each of them represented the effect by phase difference, frequency and vibration magnitude on discomfort respectively.

• 산업공학
• /
• 제12권2호
• /
• pp.247-253
• /
• 1999

The main objective of this study is to quantify the appropriateness of the sensibility vocabularies used in sensibility ergonomic evaluation scheme by applying structural equation model. In the conventional sensibility ergonomic evaluation scheme, factor analysis is employed to classify various vocabularies into some common factors. However, since the vocabularies were chosen quite subjectively, it is difficult to ascertain that they represent the product attributes properly. It was shown in a case study that the structural equation model provides the quantitative results to verify whether the selected vocabularies are eligible for further steps of sensibility ergonomic evaluation.

• 한국산학기술학회논문지
• /
• 제21권6호
• /
• pp.317-324
• /
• 2020

본 논문의 목적은 육상구조물과 비교하여 특수한 설치환경 및 목적을 가지고 있는 항만 외곽시설에 대한 보다 현실적인 침하 평가기준을 제안하는데 있다. 최근 신항만 개발 사업으로 축조된 외곽시설 특히 방파제는 먼 바다의 연약 지반에 설치되는 경우가 많다. 외곽시설은 자중으로 파랑 등의 외력에 직접 저항하는 구조물로 그 중량이 상당하여 연약 지반 위에 설치되는 경우에는 침하가 쉽게 발생하지만 구조물의 안정성 또는 기능성에 큰 영향을 주지 않는다. 하지만 현행의 안전점검 세부지침은 이러한 외곽시설의 특성을 고려하지 않은 침하 평가기준을 제시하고 있다. 이에 보다 현실적으로 외곽시설의 침하를 평가할 수 있는 간편식을 제안하였다. 간편식은 설계에서 고려한 허용잔류침하량과 침하 안정성평가 결과를 적용하여 최대 침하량을 선정하도록 하였다. 제안된 간편식의 적정성을 검증하기 위하여 최근 실시한 방파제 6개소의 측량 평가결과와 제안된 간편식 적용결과를 비교하였다. 간편식을 적용하였을 때, 기존 평가결과보다 침하 평가등급이 상향되었으며, 안정성평가 결과 적용 시에는 실제 측량결과와 거의 유사한 결과가 얻어짐을 확인할 수 있었다. 본 간편식을 활용하여 침하평가를 실시할 경우, 구조물에 안정성 및 기능수행 여부와는 무관하게 낮게 평가되는 기존의 침하평가를 보다 현실적으로 실시할 수 있을 것으로 기대된다.

• 대한기계학회논문집A
• /
• 제27권5호
• /
• pp.779-788
• /
• 2003

This study evaluates the approximation errors of the existing linearized equation for a servovalve nonlinear flowrate characteristic. At first, the errors are evaluated on flowrate/pressure characteristics diagrams. Subsequently, they are investigated with time response simulation results for several hydraulic control systems. To enable systematic evaluation of computational error, the authors propose three kinds of equations with restructured forms of the existing linearized equation. As results of the evaluations, it is ascertained that comparatively good computational accuracy can be achieved with the existing linearized equation when both an operating point for the linearized equation and operating range of the hydraulic system stay near the flowrate axis of the flowrate/pressure characteristics diagram. In addition, the results show that comparatively big computational error may occur when operating range of a hydraulic system stay apart from the flowrate axis of the flowrate/pressure characteristics diagram.

• 한국근적외분광분석학회:학술대회논문집
• /
• 한국근적외분광분석학회 2001년도 NIR-2001
• /
• pp.4113-4113
• /
• 2001

This study developed effective assay method of pharmaceutical quality control was developed by near-infrared spectroscopy (NIRS). The calibration equation model of assay was developed by 2nd deriviative PLS(Partial Least Squares) regression method with NIRS over the wavelength range from 1100 to 1400nm using diazepam tablets (2mg, 5mg). Although diazepam tablets are made by 5-different manufacture, they have similar formulation. When the correlation was compared with values by NIRS and HPLC, the R-2s and standard error of calibration (SEC) for 2mg were 0.9300 and 0.98%, the R-2s and SEC for 5mg were 0.9165 and 0.63%. The validation of the calibration equation model yield that the R-2s and standard error of prediction (SEP) for 2mg were 0.9611 and 0.995%, the R-2s and SEP for 5mg were 0.9114 and 0.842%. The method was validated on assay method for diazepam tablets by the calibration equation.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2003년도 가을 학술발표회 논문집
• /
• pp.227-234
• /
• 2003

This study presents the stress evaluation equations of circular column-box beam connection in steel frame piers. FEM analysis were carried out for circular column-box beam connection. Analysis models were made for design parameters such as joint angle, span length-width ratio(L/B), sectional-area ratio(S=A/sub w/A/sub f/), and circular column-box beam stiffness ratio(Ic/Ib). Analysis results were compared to the existing equation. Based on analysis results the stress evaluation equations of circular column-box beam connection are proposed by regression analysis.