• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2002년도 춘계학술대회 논문집
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• pp.191-194
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• 2002

The tensile properties of materials can be obtained just in accordance with conventional tensile testing methods which are described in several standards. However, the standard testing methods cannot be applicable due to the destructive testing procedure and specimen size requirement for some cases including on-service facility materials. Therefore, simple, non-destructive and advanced indentation technique was proposed. This test measures indentation load-depth curve during indentation and analyzes the mechanical properties related to deformation and fracture. In this paper, the research trend of non-destructive evaluation of tensile properties using advanced indentation system and its application fields are reviewed and discussed.

• 비파괴검사학회지
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• 제31권6호
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• pp.626-634
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• 2011

The investigation of concrete structure typically relies on visual inspection which is one of the basic inspection techniques. Image processing techniques play a crucial role in the growing field of automatic surface inspection technique. However, kinds of inspection equipment, environmental condition and detection algorithm have much influence on the reliability of inspection result. This paper proposes a verification method and testing procedure for the reliability of inspection results and surveys characteristics of image acquisition systems and crack inspection algorithms.

• 비파괴검사학회지
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• 제36권2호
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• pp.149-154
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• 2016

The use of nonlinear ultrasonics wave has been accepted as a promising tool for monitoring material states related to microstructural changes, as it has improved sensitivity compared to conventional non-destructive testing approaches. In this paper, third harmonic generation of shear horizontal guided waves propagating in an isotropic plate is investigated using the perturbation method and modal analysis approach. An experimental procedure is proposed to detect the third harmonics of shear horizontal guided waves by electromagnetic transducers. The strongly nonlinear response of shear horizontal guided waves is measured. The accumulative growth of relative acoustic nonlinear response with an increase of propagation distance is detected in this investigation. The experimental results agree with the theoretical prediction, and thus providing another indication of the feasibility of using higher harmonic generation of electromagnetic shear horizontal guided waves for material characterization.

• 한국압력기기공학회 논문집
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• 제7권1호
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• pp.41-47
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• 2011

Residual stress is the key parameter for reliability and lifetime assessment because it can reduce the fatigue strength and fracture properties of industrial structures. Recently, instrumented indentation testing (IIT) has been widely used for evaluating it, since it does not need specific specimen and time-consuming procedure. However, conventional Oliver-Pharr method, which is used for calibrating contact depth to analyze indentation load-depth curve, cannot estimate plastic pile-up between indenter and surface of specimen. Here, we introduce f parameter which is the ratio of contact depth and maximum depth, to consider pile-up height. And, its application for evaluating residual stress of weldment is introduced.

• 동아시아식생활학회지
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• 제4권1호
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• pp.19-29
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• 1994

In this paper a review of literature on Nuruk(yeast) between 1907 and 1945 was made, which showed that barley, rice bran, oat, rye, and other ingredients were originally used according to region and production quantity. Yeast can be classified into rough (Chokuk) and powder (Bunkuk) types depending on the degree of grinding. Yeast also had seasonal names, being called " Choonkuk", Hakuk", Jeolkuk", and "Dongkuk" in the spring, summer, autumn and wither respectively. The form of yeast in terms of quantity, size, and shape varied greatly by region, Production facilities were composed of plant structures to suit each process, enabling continuous output. The production process included shaping, placement in the fermenting chamber, piling by turns, risk-sifting and final output. Testing procudures were divided into visual inspection, physical testing, and chemical analyses.

• International Journal of Reliability and Applications
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• 제3권1호
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• pp.17-23
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• 2002

The class of “new better than used of a specified age” is a large and practical class of life distributions. Its properties, applicability, and testing was discussed by Hollander, Park and Proschan (1986). Their test, while remaining the yardstick for this class, suffers from weak efficiency and weak power, especially for specified ages below the average age. Thus, it is beneficial to have an alternative testing procedure that would work better for early ages and still work well for later ages. This is exactly the subject of the current note. The test developed here is also simpler than that of Hollander, et. al. (1986).

• Journal of Animal Science and Technology
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• 제46권2호
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• pp.129-136
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• 2004

The objective of present study was to ascertain parentage of Thoroughbred(TB) horses in Korea. A total of 2,029 TB horse samples including 993 foal samples for parentage testing were genotyped for nine international minimum standard markers(AHT4, 5, ASB2, HMS3, 6, 7, HTG4, 10, and VHL20). This method consisted of multiplexing PCR procedure, and showed reasonable amplification of all PCR products. Genotyping was performed with an ABI 310 genetic analyzer. The number of alleles per locus varied from 5 to 11 with a mean value of 7.33 in TB. Expected heterozygosity was ranged from 0.544 to 0.837(mean 0.709) and the total exclusion probability of 9 microsatellites loci was 0.9978. Of the 9 markers, ASB2, HMS7 and HTG10 loci have relatively high PIC value(>0.7). All of the 993 foals were qualified by compatibility according to Mendelian fashion in the present DNA typing for parentage testing. These results suggest that the present DNA typing has high potential for parentage verification of TB horses.

• Journal of Positioning, Navigation, and Timing
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• 제13권2호
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• pp.167-177
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• 2024

The Korea Augmentation Satellite System (KASS) has been certified by the Ministry of Land, Infrastructure and Transport (MOLIT) and commenced Safety-of-Life (SoL) service at the end of 2023. KASS complies with the APV-I signal-in-space performance requirements defined in the International Civil Aviation Organization (ICAO) Standards and Recommendation Practices (SARPs). The performance of KASS is verified through two steps. In the first step, design conformity from the aspect of performance is verified by both review and analysis of design and simulation. In the second step, operational conformity is tested and assessed by operational testing using real data and a deployed system with operational SWs and configurations. This paper presents a methodology, a procedure and results for the KASS operational testing. Finally, performance degradation events and results by month and region during the operational testing are presented and analyzed.

• 충청수학회지
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• 제3권1호
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• pp.97-101
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• 1990

For testing a hypothesis $H:{\theta}={\theta}_1$, vs $A:{\theta}={\theta}_2$ (${\theta}_1$ < ${\theta}_2$, we obtain a truncated sequential bayes procedure which minimizes the average sample size between ${\theta}_1$ and ${\theta}_2$.

• 정보보호학회논문지
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• 제17권2호
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• pp.51-59
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• 2007

소프트웨어 테스팅은 소프트웨어의 버그 및 잘못 구현된 부분 등을 찾아내는 과정을 통해 품질을 평가하는 방법이다. 퍼징(fuzzing)은 소프트웨어 테스팅 기술의 여러 가지 방법 중 하나로써 난수를 발생시켜 테스팅하고자 하는 소프트웨어에 주입하는 방법으로써 보안에 중점을 두어 테스팅하는 방법이다. 퍼징은 단위 시간 당 테스팅 효율성, 비용 절감 등 여러 가지 장점을 이유로 다수 사용되고 있으나 퍼징 수행 시 전문가의 개입이 많은 단점이 존재한다. 예를 들면 해당 소프트웨어가 사용하는 프로토콜 혹은 퍼징 대상이 파일인 경우 파일 포맷에 대한 분석을 수행한 후에야 가능하기 때문에 테스팅 기간이 길어질 수 있으며 퍼징 도구를 이용해도 퍼징 대상의 프로토콜 및 포맷에 대한 분석이 난해한 경우 테스팅 대상에 대한 퍼징을 수행하지 못할 수도 있다. 본 논문에서 설계한 ROAD는 RPC 기반 프로토콜 및 소프트웨어를 자동으로 퍼징할 수 있는 도구이다. RPC는 다수의 취약점이 발견된 구성요소로써 본 논문에서는 이를 자동으로 퍼징할 수 있는 도구의 구현을 목표로 하였다. 기존의 도구 중 RPC 기반 소프트웨어를 퍼징하는 도구가 존재하지만 자동화되어 있지 않을 뿐만 아니라 소프트웨어에 따라 도구를 수정해야만 사용이 가능하다. 본 논문은 이러한 단점을 극복하고자 자동화 도구를 설계 및 구현하여 실제 RPC 기반 프로토콜 및 소프트웨어에 적용하였다. 또한 실험을 통해 도구의 효용성을 검증하였다.