• Communications for Statistical Applications and Methods
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• v.12 no.1
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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.

• IEMEK Journal of Embedded Systems and Applications
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• v.5 no.1
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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.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.12
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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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• v.15 no.8
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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.

• Journal of the Korea Society of Computer and Information
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• v.13 no.2
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• pp.19-29
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• 2008

In case of unit testing, White-box test can be used to closely check source code and to analyze logic and statement errors. On the other hand, in case of function testing of system level, Black-box test can be mainly used to compare actual and expected results by inputting test data because the scale of function is large. This Black-Box test in system testing level has problem in tracing errors in source code when we find errors. Moreover applying White-box test is not easy for system testing level because the levels of test target are different. Therefore this paper suggests the vertical test method of a practical and integrated system level which can checks up to source code level using White-box test style although it aims to test the highly abstract level like a system function. In addition, the experiment explains how to apply the vertical test by displaying an example which traces from UML specification model to the source code and also shows efficiency of error trace.

• Proceedings of the KIEE Conference
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• 2001.07a
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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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• v.40 no.6
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• pp.453-457
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• 2016

In various industrial plants such as power generation plants, petrochemical plants, and unit factories, there is an increasing demand for a system that generates hot water using waste or surplus steam. Compact steam unit (CSU), which produces hot water by using steam, is a good solution considering energy reuse. In this study, as a basic study to develop a high-pressure CSU, heat transfer characteristics of a hybrid heat exchanger were investigated through experiments, in order to use the hybrid heat exchanger instead of a conventional plate heat exchanger as the core component of CSU. The experimental results are the followings. Heat balance between the hot side and cold side was satisfied within ${\pm}5%$. Overall heat transfer coefficient increased linearly as the Reynolds number increased and exceeded $5,524W/m^2K$ when the flow velocity was above 0.5 m/s. In addition, pressure drop also increased as the Reynolds number increased, and pressure drop per unit length was below 50 kPa/m.

• Physical Therapy Korea
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• v.18 no.3
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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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• v.6 no.4
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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.

• Journal of Korean Society for Quality Management
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• v.29 no.4
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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.