• Communications for Statistical Applications and Methods
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• 제12권1호
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• pp.101-115
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• 2005

We propose in this article a procedure for testing unit and fractional orders of integration, with the roots simultaneously occurring in the trend, the seasonal and the cyclical component of the time series. The tests have standard null and local limit distributions. However, finite sample critical values are computed, and several Monte Carlo experiments conducted across the paper show that the rejection frequencies against unit (and fractional) orders of integration are relatively high in all cases. The tests are applied to the UK consumption and income series, the results showing the importance of the roots corresponding to the trend and the seasonal components and, though the unit roots are found to be fairly suitable models, we show that fractional processes (including one for the cyclical component) may also be plausible alternatives in some cases.

• 대한임베디드공학회논문지
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• 제5권1호
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• pp.29-38
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• 2010

It is highly requested that the more complicated embedded software is used for high performance and multiple functions of the systems. This is inevitably increasing the errors. Therefore the embedded software testing is getting important recently. There are not general testing methods which are able to be applied for any embedded systems, but via this research, we introduce a testing method which is based on TTCN-3, a testing standard, for embedded systems. A testing environment for network-based embedded software is implemented with considering the features of TTCN-3 testing which is based on message exchange. The testing environment has two additional parts with TTCN-3 test system, the network analyzer to access the network-based systems and the communication interface which is suggested for embedded systems in previous work, and we have implemented the whole testing environment with interacting these two parts. In addition to the normal testing domain, called single node testing as a unit testing of V-model, we suggest another concept to test multiple nodes in network. It could be achieved by adding keywords such as supervisor and object which are describing the feature of TTCN-3 testing component and generating the TTCN-3 Executable code which contains new keywords. The testing has done for embedded software which is based on CAN network and the demonstration of the testing environment has been shown in this paper.

• 대한전기학회논문지
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• 제39권12호
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• pp.1296-1305
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• 1990

Common enclosure type SF6 circuit breakers have been developed in many countries for their compact design and economical merits, but their performance testing method is one of the difficult problems because of the limitation of testing capacity. This paper studies a three phase synthetic testing circuit which consists of 4-unit circuits based on the current injection method. This new synthetic testing circuit can be used in both ways of three phase testing up to 242kV rating and single phase testing up to 800kV rating.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권8호
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• pp.2974-2992
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• 2021

Crowd-based outsourcing is an emerging trend in testing, which integrates advantages of crowd-based outsourcing in software testing. Open call format is used to accomplish various network tasks involving different types of testing levels and techniques at various places by software testers. Crowd-sourced software testing can lead to an improper testing process as if it does not allocate the right task to the right crowd with required skills and not choose the right crowd; it can lead to huge results, which become time-consuming and challenging crowd-source manager for the identification of improper one. The primary purpose of this research is to make crowd-based outsourced software testing more effective and reliable by relating association between the software tester, personality characteristic, and different levels of software testing, i.e., unit, integration, and system, in order to find appropriate personality characteristic for required testing level. This research has shown an observed experiment to determine which software testing level suits which personality characteristic tester in a crowd-based software testing environment. A total of 1000 software testers from different software houses and firms in Pakistan were registered to perform tasks at different software testing levels. The Myers-Briggs Type Indicator (MBTI) test is used to identify each tester's personality characteristic involved in this research study.

• 한국컴퓨터정보학회논문지
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• 제13권2호
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• pp.19-29
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• 2008

단위 시험은 모듈의 소스 코드를 면밀히 검토하면서 논리적 오류나 문장 오류 등이 있는지 분석하는 화이트박스 시험이 가능하다. 반면 시스템 수준의 기능 시험은 규모가 크기 때문에 시험 데이터를 입력한 후 출력된 결과가 예상 결과와 같은지 비교하는 블랙박스 시험이 주를 이룬다. 이러한 시스템 시험 단계에서 사용하는 블랙박스시험은 오류를 발견하더라고 수정을 위해 소스 코드를 추적하기 어려운 문제점이 있다. 뿐만 아니라 시스템 시험 단계에 화이트박스 시험을 사용하는 것은 시험 대상의 추상 수준 달라 쉽지 않다. 이에 본 논문에서는 시스템의 기능처럼 높은 추상 수준을 시험 대상으로 하되 소스 코드 수준까지 화이트박스 스타일로 시험할 수 있는 현실적이고 통합된 시스템 수준의 수직적 시험에 대해 제안한다. 그리고 어떻게 수직적 시험을 적용하는지 UML명세 모델에서 소스코드까지 오류를 추적하는 방법을 사례를 통해 설명하고 더불어 오류 추적의 효과성을 보였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.446-448
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• 2001

We have developed the testing software for KEPCO operators to maintain the small-scale distribution automation system effectively. The testing software is used to monitor the present status, to measure the analog value(voltage, amperage) and to control the switch and FRTU(Feeder Remote Terminal Unit) in order to find out a disabled part of the system. And at the stage of inspection of the switch and FRTU, it can screen the inferior one.

• Journal of Advanced Marine Engineering and Technology
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• 제40권6호
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• pp.453-457
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• 2016

발전 플랜트, 석유 화학 플랜트, 단위 공장과 같은 다양한 산업 플랜트에서, 사용 후 스팀이나 잉여 스팀을 이용하여 온수나 급탕수를 만드는 시스템의 수요가 증가하고 있다. 스팀을 사용하여 온수를 제조하는 장치인 컴팩트 스팀 유닛(Compact Steam Unit, 이하 CSU)가 에너지 재활용 측면에서 좋은 대안이 되고 있다. 본 연구에서는 고압 CSU 개발을 위한 기초 연구로서, CSU의 핵심 부품인 열교환기로 기존 판형 열교환기 대신 하이브리드 열교환기를 적용하여 위해, 실험적인 방법으로 하이브리드 열교환기의 전열 특성을 파악하고자 하였다. 실험 결과, 온수측과 냉수측 사이의 열 평형은 ${\pm}5%$ 이내를 만족하였다. 레이놀즈 수가 증가함에 따라, 총괄 열전달 계수는 선형적으로 증가하였으며, 채널 유속 0.5 m/s 이상에서 총괄 열전달 계수는 개발 목표치인 $5,524W/m^2K$를 초과하였다. 레이놀즈 수가 증가함에 따라, 압력 강하 또한 증가하였으며, 단위 길이당 압력 강하값은 유속 0.5 m/s에서 50 kPa/m 이하였다.

• 한국전문물리치료학회지
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• 제18권3호
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• pp.67-75
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• 2011

The purpose of this study was to assess the agreement of manual muscle testing (MMT) and test-retest reliability of a hand held dynamometer for the posterior gluteus medius muscle, with and without lumbar stabilization, using a pressure biofeedback unit for patients with low back pain. The pressure biofeedback unit was used to minimize the substitute motion of the lumbopelvic region during hip abduction in patients lying on their side. Fifteen patients with low back pain participated in this study. A tester determined the MMT grades of the posterior gluteus medius with and without the pressure biofeedback unit. Active hip abduction range of motion with an inclinometer and the strength of their posterior gluteus medius using a hand held dynamometer were measured with and without the pressure biofeedback unit in the MMT position. The agreement of the grade of muscle strength in the MMT, and intra-rater reliability of both the active hip abduction range of motion and the strength of posterior gluteus medius were analyzed using the weighted kappa and intraclass correlation coefficient (ICC), respectively. The agreement of MMT with the pressure biofeedback unit (weighted kappa=.92) was higher than the MMT (weighted kappa=.34)(p<.05). The inclinometer with pressure biofeedback unit measurement of the active hip abduction range of motion had an excellent intra-rater reliability (ICC=.90). Also, the hand held dynamometer with pressure biofeedback unit measure of strength of the posterior gluteus medius had a good intra-rater reliability (ICC=.85). Therefore, the test for muscle strength with pressure biofeedback unit will be a reliable method for the determination of the MMT grades or amount of posterior gluteus medius muscle strength and the measurement of the range of motion for hip abduction in patients with low back pain.

• Current Optics and Photonics
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• 제6권4호
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• pp.381-391
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• 2022

Two-photon-polymerization additive-manufacturing systems feature high resolution and precision. However, there are few reports on specific methods and possible problems concerning the use of small lasers to independently build such platforms. In this paper, a femtosecond-laser two-photon-polymerization additive-manufacturing system containing an optical unit, control unit, monitoring unit, and testing unit is built using a miniature femtosecond laser, with a detailed building process and corresponding control software that is developed independently. This system has integrated functions of light-spot detection, interface searching, micro-/nanomanufacturing, and performance testing. In addition, possible problems in the processes of platform establishment, resin preparation, and actual polymerization for two-photon-polymerization additive manufacturing are explained specifically, and the causes of these problems analyzed. Moreover, the impacts of different power levels and scanning speeds on the degree of polymerization are compared, and the influence of the magnification of the object lens on the linewidth is analyzed in detail. A qualitative analysis model is established, and the concepts of the threshold broadening and focus narrowing effects are proposed, with their influences and cooperative relation discussed. Besides, a linear structure with micrometer accuracy is manufactured at the millimeter scale.

• 품질경영학회지
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• 제29권4호
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• pp.92-102
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• 2001

Software testing during development and operation should exercise to obtain the desired software quality and leave failure data set. So far, many software reliability models are classified and can be used to measure a software reliability only based on its failure history But, in practice, developers or testers of software systems must decide which existing software reliability model can be fitted. In this paper, we will show that an appropriate reliability model can be selected by considering relations between characteristics of each testing environment and models' assumptions. Several methods of software testing are presented and discussed. Also, unit test, integrated test, function test and system test that are sequentially exercised during development will be introduced.