• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.3 s.234
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• pp.387-394
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• 2005

Accurate predictions and simulations of the behavior of space structures based on analytical models become more important. In order to perform analysis to support the design of Ku-band transponder panel for the Communications and Broadcasting Satellite(CBS), mathematical models of the panel were generated in the form of finite element models. Test verification of these models is required before the transponder panel can be certified for launch environments. A modal identification was performed to obtain modal parameters which can be compared with the test results using correlation techniques. This paper approaches the sensor placement from the standpoint of the structural dynamicist who uses the modal parameter obtained during launch environmental test. The models were validated by performing a test-analysis correlation and updating analysis. It was proved that the Ku-band transponder panel satisfies the environmental test requirements.

• Journal of Korean Society on Water Environment
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• v.31 no.1
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• pp.49-54
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• 2015

Acute toxicity test with Daphnia magna has a variety of factors such as incubation condition of test species, food quality and proficiency of laboratory workers. Therefore, proper proficiency testing samples were required for evaluating the competence of laboratory workers. This study aims to propose some appropriate proficiency testing samples for laboratory workers of acute toxicity test with Daphnia magna. Proposed four kinds of standard samples (Sample A, B, C, and D) for proficiency testing were selected from reference materials which were recommended from Canada and USA WET(Whole Effluent Toxicity) authorities. Proposed standard samples were tested by trial application of proficiency testing, homogeneity and stability checks using repeatability test. Sample A, C and D were estimated ad the suitable candidates for proficiency test standard samples except for Sample B. In addition, Sample A was proved to be the most suitable sample.

• Toxicological Research
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• v.22 no.4
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• pp.423-429
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• 2006

Recent reports on the photocarcinogenicity and photogerotoxicity of many compounds led to an increasing awareness for the need of a standard approach to test for photogenotoxicity. The comet assay has been recently validated as a sensitive and specific test system for the quantification of DNA damage. Thus, the objectives of this study are to investigate the utility of photo-comet assay for detecting photo-mutagens, and to evaluate its ability to predict rodent photo-carcinogenicity. Photo-comet assays were performed using L5178Y $Tk^{+/-}$ mouse lymphoma cells on five test substances (8-methoxypsoralen, chlorpromazine, lomefloxacin, anthracene and retinoic acid) that demonstrated positive results in photocarcinogenicity tests. For the best discrimination between the test substance-mediated DNA damage and the undesirable DNA damage caused by direct UV absorption, a UV dose-response of the cells in the absence of the test substances was firstly fnalized. Out of 5 test substances, positive comet results were obtained for chlorpromazine, lomefloxacin, anthracene and retinoic acid while 8-methoxypsoralen found negative. An investigation into the predictive value of this photo-comet assay for determining the photocarcinogenicity showed that photo-comet assay has relatively high sensitivity. Therefore, the photo-comet assay with mammalian cells seems to be a good and sensitive predictor of the photocarcinogenic potential of new substances.

• Journal of the Korean Data and Information Science Society
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• v.24 no.1
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• pp.73-83
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• 2013

Among class quantitative tests for the credit rating systems, the credit rating tests for calibration are to test the class homogeneous differences between observed and predicted probabilities. For one time period, binomial test and chi-square test are included, and normal test and extended traffic lights test are also contained for several time peroids. In this work, we consider real data in which there exists correlation among variables, so that these test methods could be applied to the credit rating systems as well as various kinds of the class data such as BWT data and FSI data.

• KSBB Journal
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• v.19 no.2
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• pp.132-137
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• 2004

Biodegradability test for various synthetic lubricant oil bases derived from biodiesel was carried out. The biodegradability was estimated under aerobic aqueous condition, according to the method by OECD 301 B, which is based on CO$_2$ evolution test. The ultimate biodegradability of pentaerythritol methyl esters were estimated as 61.1∼80.3%, at 28 day with which the test compounds were indicated as ultimately biodegradable. Among the tested samples, biodiesel showed the highest biodegradability (83.5%). The validation with several criteria, regarding relative errors of test results, toxicity control and procedure control, was performed through the biodegradability test. The test procedure was validated for all the tested lubricant oil bases and biodiesel, except for petroleum diesel.

• Mass Spectrometry Letters
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• v.10 no.3
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• pp.93-101
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• 2019

Algorithms and software for predicting tandem mass spectra have been developed in recent years. In this work, we explore how distinct in silico $MS^2$ spectra are predicted for isomers, i.e. compounds having the same formula and similar molecular structures, to differentiate between them. We used the CFM-ID 2.0/3.0 predictor with regard to (a) test compounds, whose experimental mass spectra had been randomly sampled from the MassBank of North America (MoNA) collection, and to (b) the most widespread isomers of test compounds searched in the PubChem database. In the first validation test, in silico mass spectra constitute a reference library, and library searches are performed for test experimental spectra of "unknowns". The searches led to the true positive rate (TPR) of ($46-48{\pm}10$)%. In the second test, in silico and experimental spectra were interchanged and this resulted in a TPR of ($58{\pm}10$)%. There were no significant differences between results obtained with different metrics of spectral similarity and predictor versions. In a comparison of test compounds vs. their isomers, a statistically significant correlation between mass spectral data and structural features was observed. The TPR values obtained should be regarded as reasonable results for predicting tandem mass spectra of related chemical structures.

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.776-792
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• 2021

Conventional integral effect test facilities were constructed to enable the precise observation of thermal-hydraulic phenomena and reactor behaviors under postulated accident conditions to prove reactor safety. Although these facilities improved the understanding of thermal-hydraulic phenomena and reactor safety, applications of new technologies and their performance tests have been limited owing to the cost and large scale of the facilities. Various nuclear technologies converging 4th industrial revolution technologies such as artificial intelligence, drone, and 3D printing, are being developed to improve plant management strategies. Additionally, new conceptual passive safety systems are being developed to enhance reactor safety. A new integral effect test facility having a noticeable scaling ratio, i.e., the (UNIST reactor innovation loop (URI-LO), is designed and constructed to improve the technical quality of these technologies by performance and feasibility tests. In particular, the URI-LO, which is constructed using a transparent material, enables better visualization and provides physical insights on multidimensional phenomena inside the reactor system. The facility design based on three-level approach is qualitatively validated with preliminary analyses, and its functionality as a test facility is confirmed through a series of experiments. The design feature, design validation, functionality test, and future utilization of the URI-LO are introduced.

• Journal of the Korean Society of Systems Engineering
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• v.16 no.2
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• pp.110-117
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• 2020

In this paper, we estimated the straight line stability by performing a 3 degree of freedom spiral test simulation of a intact/damaged surface combatant using the hydrodynamic coefficient obtained through the PMM(Planar motion mechanism) test based on system engineering process. A model ship was ONR Tumblehome and damaged compartment was set on the starboard bow. As a result of conducting a spiral test simulation based on the experimental results of J.Ha (2018), the asymmetric straight line stability due to the damaged compartment was confirmed. In the case of a ship in which the starboard bow was damaged, it was confirmed that it had the characteristic to deflect to the left when going straight. Also, when estimating the straight line stability of a both port and starboard asymmetric surface combatant, a separated equation of motion model that sees the port and starboard as different ships seems suitable.

• 대한예방의학회:학술대회논문집
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• 1994.02b
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• pp.137-141
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• 1994

The purpose of this paper is to examine what is meant by a ralid measure of health. Guyatt, Kirshner and Jaeschke propose that health tests should be designed so as to have one of several kinds of validity: 'longitudinal construct validity' for those which are used for longitudinal research designs, and 'cross-sectional construct validity' for those which are used for cross-sectional designs. Williams and Naylor argue that this approach to test classification and validation confuses what a test purports to measure with the purpose for which it is used, and that some tests have multiple uses. A review of the meanings of validity in the psychologica test literature shows that both sets of authors use the term validity in an idiosyncratic way. Although the use of a test (evaluated by content validity) should not be conflated with whether the test actually measures a specified construct (evaluated by construct validity);' if health is actually made up of several constructs (as suggested in Hyland's interactional model) then there may be an association between types of construct and types of purpose. Evidence is reviewed that people make several, independent judgements about their health: cognitive perceptions of health problems are likely to be more sensitive to change in a longitudinal research design. whereas emotional evaluations of health provide less bias in cross-sectional designs. Thus. a classification of health measures in terms of the purpose of the test may parallel a classification in terms of what tests purport to measure.

• Proceedings of the Safety Management and Science Conference
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• 2001.05a
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• pp.77-81
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• 2001

Burn-in is a test procedure to find and eliminate the inherent initial failure of a product during or at the final stage of production process. Software testing is the validation and verification process which is used to cut off the faults from a software. The two have the common function and objective of "debugging". This article summarizes some significant models on the optimal hardware and software burn-in time, and provides the relevant paper lists. The need for the development of the unified burn-in policy of a hardware-software system is addressed.addressed.