• 한국산림과학회지
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• 제94권2호통권159호
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• pp.82-89
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• 2005

The purpose of this paper is to investigate index numbers by conducting various comparisons among the widely used index formulas. The comparison is considered in three ways; 1) divergences in the magnitudes of index numbers due to the use of different formulas (Laspeyres, Paasche, Fisher, and Tornqvist); 2) the effect of selection of base year (fixed-year base vs. chain-type); 3) the degree of approximation of indirect to direct quantity index. The empirical application is to sawmills and planing mills industry of U.S. using a national time series data covering years of 1948-2000. The results show that the differences between Laspeyres and Paasche index can be substantial in some cases while the difference between Fisher and Tornqvist index is minimal. We also confirm that the selection of base year can cause significant divergences, especially when the variables undergo rapid price or quantity changes over time. We find that indirect quantity index approximates direct quantity index reasonably well in U.S. sawmill industry.

• Geomechanics and Engineering
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• 제12권6호
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• pp.871-882
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• 2017

Indirect measure of the tensile strength of laboratory samples is an important topic in rock engineering. One of the most important tests, the Brazilian strength test is performed to obtain the tensile strength of rock, concrete and other quasi brittle materials. Because the measurements are provided indirectly and the inspected rock materials may have heterogeneous properties, uncertainty quantification is required for a reliable test evaluation. In addition to the conventional measurement evaluation uncertainty methods recommended by the Guide to the Expression of Uncertainty in Measurement (GUM), such as Taylor's and Monte Carlo Methods, a fuzzy set-based approach is also proposed and resulting uncertainties are discussed. The results showed that when a tensile strength measurement is measured by a laboratory test, its uncertainty can also be expressed by one of the methods presented.

• International Journal of Naval Architecture and Ocean Engineering
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• 제5권3호
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• pp.392-403
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• 2013

For the analysis of radiating noise problems in medium-to-high frequency ranges, the Energy Flow Boundary Element Method (EFBEM) was developed. EFBEM is the analysis technique that applies the Boundary Element Method (BEM) to Energy Flow Analysis (EFA). The fundamental solutions representing spherical wave property for radiating noise problems in open field and considering the free surface effect in underwater are developed. Also the directivity factor is developed to express wave's directivity patterns in medium-to-high frequency ranges. Indirect EFBEM by using fundamental solutions and fictitious source was applied to open field and underwater noise problems successfully. Through numerical applications, the acoustic energy density distributions due to vibration of a simple plate model and a sphere model were compared with those of commercial code, and the comparison showed good agreement in the level and pattern of the energy density distributions.

• 대한치과교정학회지
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• 제21권3호
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• pp.513-520
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• 1991

The purpose of this study was to compare the bracket placement and the shear bond strength of indirect-bonded brackets with those of direct-bonded ones. Forty eight extracted human teeth were collected and attached with brackets and tested on shear bond strength, using Instron. Fourteen patients from Wonkwang University Dental Hospital were selected for direct bonding of brackets and their teeth were measured on bracket angulation and bracket height. The obtained results were as follows: 1. The shear bond strengths of incisors were higher in direct-bonding,group, rather than in-direct-bonding group. But, the shear bond strength of premolars showed no significant differences between groups. 2. The bracket angulations of indirect-bonding group were preciser than those of direct-bonding group, especially in upper first premolars, lower lateral incisors, canines, premolars. 3. In bracket height, there were no significant differences between groups.

• 한국기계가공학회지
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• 제10권6호
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• pp.122-127
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• 2011

In this study, it was compared collecting performance according to contact types between heatpipe and manifold of vacuum tube type solar collector. Between two types, direct contact type is better in collecting performance. On the other hand, Indirect type have advantage in maintenance. In the result of numerical analysis, As the temperature of heatpipe and flow rate of working fluid increased, difference of outlet mean temperature of two types became large. Also, it could be confirmed, as contact resistance between heatpipe and copper tube in indirect type increased, the difference increased too. Useful data in selection and design in vacuum tube type solar collector were proposed by the results of numerical analysis.

• Transactions on Control, Automation and Systems Engineering
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• 제3권1호
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• pp.32-42
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• 2001

In this paper, a parameter estimator is developed for the plant model whose structure is represented by the Takagi-Sugeno model. The essential idea behind the on-line estimation is the comparison of the measured stated with the state of an estimation model whose structure is the same as that of the parameterized model. Based on the parameter estimation scheme, and indirect Model Reference Adaptive Fuzzy control(MRAFC) scheme is proposed to provide asymptotic tracking of a reference signal for the systems with uncertain for slowly time-varying parameters. The developed control law and adaptive law guarantee the boundedness of all signals in the closed-loop systems. In addition, the plant state tracks the state of the reference model asymptotically with time for any bounded reference input signal.

• 대한치과보철학회지
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• 제55권3호
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• pp.264-271
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• 2017

목적: 본 연구에서는 4종의 간접복합레진에 대하여 금합금과 Ni-Cr합금에 대한 결합강도의 차이와 각각의 합금에 표면형태를 다르게 하여 일정한 온도의 증류수에 보관 전과 후에 전단결합강도의 차이가 있는지 알아보고자 하였다. 재료 및 방법: 금속 시편을 주조 제작하였는데, 금합금과 Ni-Cr합금의 표면형태를 flatting, bead, loop로 하여 4종의 간접복합레진(Gradia, Tescera Sinfony and in;joy)당 60개씩 총 240개를 준비하였다. 이후 금속표면에 각각의 제조사에서 지시한대로 간접 복합레진을 접착하였다. 간접복합레진의 중합 24시간 후에 만능시험기를 이용하여 전용 지그에 금속시편을 부착 후, 전단결합강도를 측정하였다. 또한 증류수에 240시간 보관 후에 같은 방법으로 전단결합강도를 측정하였다. 결과: 금속의 표면 형태에 따른 전단결합강도 측정에서 4종의 레진 모두 bead군에서 높은 결합강도를 보였고 loop, flatting 순이었다 (P < .05). 수조에서 240시간 보관 후에는 Gradia가 모든 군에서 다른 레진 군에 비해 비슷하거나, 통계적으로 유의하게 높은 (P < .05) 전단결합강도를 나타내었다. 결론: 금속표면의 형태에 따라, 금속의 종류에 따라, 물속 보관 전후에 따라 금속과 간접복합레진의 결합력의 차이를 나타내었고 추가 실험을 통해 최적의 조합에 따른 임상에서의 적용가능성을 보여주었다.

• Journal of Preventive Medicine and Public Health
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• 제34권3호
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• pp.269-276
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• 2001

Objectives : To evaluate the internal burden and hazardous effects associated with smoking in middle and high school students. Methods : We analysed urinary cotinine(U-cotinine) concentrations and the frequency of Sister Chromatid Exchanges (SCE). A comparison was done of U-cotinine concentrations and the frequency of SCE in peripheral lymphocytes across school levels (middle vs. high) and smoking types (direct: daily & occasional smoking, indirect; usual indirect & non-smoking), in 122 males. Results : The middle school student group comprised 6.8% daily smokers, 15.9% occasional smokers, 40.9% daily indirect smokers, and 35.4% nonsmokers, while the high school student group comprised 18.0%, 20.5%, 35.7%, and 21.8%, respectively. The U-cotinine concentration and the frequency of SCE among the middle school students were $79.11{\mu}g/l$ and 2.0 per cell, respectively, which were significantly lower than the $146.85{\mu}g/l$ (p=0.078) and 2.6 per cell (p=0.005) of the high school students. Among the 40 direct smokers, these two biomarkers were $236.66{\mu}g/l$ and 2.59 per cell, significantly higher than the $67.33{\mu}g/l$ (p=0.0001) and 2.1 per cell (p=0.003) among indirect smoking groups. The variation in individual U-cotinine concentration ranged widely in both the indirect and direct smoking groups. Conclusion : Urinary cotinine concentrations and the frequency of Sister Chromatid Exchange seem to objectively and effectively evaluate student exposure whether it was direct or indirect smoking. Consequently, these biomarkers may be useful in monitoring the objective efficacy of anti-smoking programs in adolescent populations.

• 한국소프트웨어감정평가학회 논문지
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• 제16권1호
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• pp.37-44
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• 2020

소프트웨어의 유사성 비교는 소스코드를 대상으로 한다. 소스코드는 프로그램 언어로 표현된 개발자의 지적 저작권으로 보호된다. 문서형식으로 작성된 프로그램 소스코드는 개발자의 전문지식과 아이디어가 포함된 내용을 포함하고 있다. 소프트웨어 저작권의 불법도용을 판단하기 위한 감정 작업은 원본과 비교본의 소스 코드를 대상으로 파일의 구성과 내용을 검증하는 방법으로 수행된다. 그러나 실제적으로 피고소인 측의 불성실한 목적물 제공으로 소스코드의 일대일 비교감정이 어려운 상황이 증가하고 있다. 이 경우 실행코드에 대한 비교감정이 수행되어야 하며, 역어셈블 방법, 역공학기법, 기능실행의 시퀀스 분석 등의 간접적인 방법이 적용된다. 본 논문에서는 소스코드제공이 어려운 상황에서 시스템과 실행코드 파일을 대상하는 하는 감정 사례를 통해 간접적인 비교결과의 유효성에 대해 분석하고, 감정결과에 활용하는 방안을 제시한다.

• 한국소프트웨어감정평가학회 논문지
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• 제17권2호
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• pp.31-38
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• 2021

소스코드 감정목적물의 유사성을 판단하는 경우, 양측의 비교대상 소스코드는 컴파일과 실행이 가능 해야 한다. 또한 시스템 소스의 경우에는 하드웨어와의 인터페이스가 일치하는지 확인이 되어야 한다, 그러나 현실적으로 분쟁당사자의 소스코드가 완전하지 않은 상태로 제공되는 경우가 발생하고 있다. 분쟁을 제기하는 측에서는 동작 특성이 자사의 기능과 유사하고, 출력되는 표현과 기능이 유사한 이유로 소스코드의 핵심부분이 유사한 것으로 판단하고, 감정을 요청하고 있다. 분석과정에서 소스코드의 컴파일 오류 발생 시, 감정인은 소스코드의 흐름도를 작성하고, 함수별 코드의 흐름을 추적하는 방법을 적용하게 된다. 그러나 이 방법은 간접적이고, 감정인의 주관적인 판단이 적용되어 유사성 분석결과에 객관성에 대한 다툼이 우려된다. 본 연구에서는 임베디드 시스템에 적용된 소스코드분쟁의 감정사례를 통해 검증되지 않은 소스코드 유사성 도출의 문제점과 개선 방향을 다룬다.