• Nuclear Engineering and Technology
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• v.23 no.2
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• pp.174-182
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• 1991

Effects of human error relevant to the periodic test are incorporated in the evaluations of the unavailability and optimal test interval of a safety system. Two types of possible human error with respect to the test and maintenance are considered. One is the possibility that a good safety system is inadvertently left in a bad state after test（Type A human error) and the other is the possibility that a bad safety system is undetected upon the test（Type B human error). An event tree model is developed for the steady-state unavailability of a safety system in order to determine the effects of human errors on the system unavailability and the optimal test interval. A reliability analysis of the Safety Injection System (SIS) was peformed to evaluate the effects of human error on the SIS unavailability. Results of various sensitivity analyses show that ; (1) the steady-state unavailability of the safety system increases as the probabilities of both types of human error increase and it is far more sensitive to Type A human error, (2) the optimal test interval increases slightly as the probability of Type A human error increases but it decreases as the probability of Type B human error increases, and (3) provided that the test interval of the safety injction pump is kept unchanged, the unavailability of SIS increases significantly as the probability of Type A human error increases but slightly as the probability of Type B human error increases. Therefore, to obtain the realistic result of reliability analysis, one should take shorter test interval (not optimal test interval) so that the unavailability of SIS can be maintained at the same level irrespective of human error. Since Type A human error during test & maintenance influeces greatly on the system unavailability, special efforts to reduce the possibility of Type A human error are essential in the course of test & maintenance.

• Biomolecules & Therapeutics
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• v.3 no.3
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• pp.242-244
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• 1995

In vitro cell culture system has been proposed as a promising alternative model to in vivo skin irritation test. These studies were performed to screen the cytotoxicity effects of surfactants using normal human skin fibroblasts. Cell membrane integrity assessed by the leakage of lactate dehydrogenase (LDH) and mitochondrial integrity by MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromides reduction test were affected in a dose dependent manner. The irritation potential of surfactants to human skin patch test, and the changes of capillary permeability by rabbit intradermal safety test were assessed as in vivo methods. Our results suggest that LDH leakage assay and MTT reduction test using cultured human fibroblasts could be predictive for the irritancy of various surfactants in human, and LDH assay is superior correlated with in vivo test (r=0.886) to MTT test with in vivotest (r=0.757).

• Journal of the Korea Society of Computer and Information
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• v.20 no.10
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• pp.45-51
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• 2015

In this paper, we propose a way to reduce the SW reliability test time and human errors by utilizing the Lean Six Sigma methodology as a troubleshooting tool. Recently, SW technology is rapidly changing and the importance of SW management has been recognized. Accordingly, the SW reliable test for the SW development outcomes in one of the methods for SW quality improvement is required. However, it consumes a lot of development costs, has the time constraints and human errors in SW reliable test, so, it is difficult to meet the requirements for SW test.

• Toxicological Research
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• v.33 no.3
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• pp.191-203
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• 2017

Human eyes and skin are frequently exposed to chemicals accidentally or on purpose due to their external location. Therefore, chemicals are required to undergo the evaluation of the ocular and dermal irritancy for their safe handling and use before release into the market. Draize rabbit eye and skin irritation test developed in 1944, has been a gold standard test which was enlisted as OECD TG 404 and OECD TG 405 but it has been criticized with respect to animal welfare due to invasive and cruel procedure. To replace it, diverse alternatives have been developed: (i) For Draize eye irritation test, organotypic assay, in vitro cytotoxicity-based method, in chemico tests, in silico prediction model, and 3D reconstructed human cornealike epithelium (RhCE); (ii) For Draize skin irritation test, in vitro cytotoxicity-based cell model, and 3D reconstructed human epidermis models (RhE). Of these, RhCE and RhE models are getting spotlight as a promising alternative with a wide applicability domain covering cosmetics and personal care products. In this review, we overviewed the current alternatives to Draize test with a focus on 3D human epithelium models to provide an insight into advancing and widening their utility.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.855-860
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• 2007

This paper describes a human driver model developed based on finite preview optimal control method. The human driver steering model is constructed to minimize a performance index which is a quadratic form of lateral position error, yaw angle error and steering input. Simulation studies are conducted using a vehicle simulation software, Carsim. The Carsim vehicle model is validated using vehicle test data. In order to validate the human driving steering model, the human driver steering model is compared to the driving data on a virtual test track(VTT) and the actual vehicle test data. It is shown that human driver steering behaviors can be well represented by the human driver steering model presented in this paper

• Journal of the Ergonomics Society of Korea
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• v.16 no.1
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• pp.107-117
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• 1997

It is necessary to evaluate HMI inaspects of human factors in the design stage of MMIS(man machine interface system) and feedback the result of evaluation because operators performance is mainly influenced by the HMI. Therefore, the MMIS design should be reflected the operators psychological, behavioral and physiological characteristics in the interaction with human machine interface(HMI) in order to improve the safety and availability of the MMIS of a nuclear power plant(NPP) by reduction of human error. The development of human factors experimental evaluation techniques and integrated test facility(ITF) for the human factors evaluation become an important research field to resolve hi,am factors issues on the design of an advanced control room(ACR). We developed am ITF, which is aimed to experiment with the design of the ACR and the human machine interaction as it relates to the control of NPP. This paper presents the development of an ITF that consists of three rooms such as main test room(MTR), supporting test room(STR) and experiment control room(ECR). And, the ITF has a various facilities such as a human machine simulator(HMS), experimental measurement systems and data analysis and experiment evaluation supporting system(DAEXESS). The HMS consists of full-scope simulation model of Korean standard NPP and advanced HMI based on visual display nits (VDUS) such as touch color CRT, large scale display panel(LSDP), flat panel display unit and so on.

• Journal of Korean Dental Science
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• v.14 no.2
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• pp.51-60
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• 2021

Purpose: Measuring viability of a three-dimensional in vitro organotypic human oral tissue model has been suggested as an alternative test method to the oral mucosa irritation test of oral care products. The aim of this study was to investigate the production of two different cytokines using organotypic human oral tissue model following exposure to chemicals that are commonly used in oral care products. Materials and Methods: The organotypic human oral tissues were exposed to ethanol, sodium lauryl sulphate or hydrogen peroxide for 90 minutes. Following exposure, interleukin (IL)-1α and IL-8 productions were assessed and correlated with cell viability testing as well as histology of the organotypic human oral tissues. Result: High levels of IL-8 were released from organotypic human oral tissues in all of the test and control groups without any significant differences between them. In contrast, differences were found in IL-1α release between the test and control groups. Additionally, the trend of IL-1α release corresponded to the phenotypes observed in histological analysis while different trend existed between IL-1α release and cell viability. Conclusion: The study concluded the non-specific release of IL-8 for the assessment of oral care product chemicals' toxicity, while potential of measuring IL-1α cytokine level as the possible alternative test method.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.693-697
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• 2015

Our aims were to evaluate the clinical performance of human telomerase RNA gene component (hTERC gene) amplification assay with high-risk human papillomavirus (HR-HPV) DNA test of Hybrid Capture 2 DNA test (HC2), for the detection of high grade cervical precancerous lesions and cancer (CIN 2+). In addition, the association shown between hTERC gene amplification and HPV DNA test positive in women with and without cervical neoplasia was assessed. There were 92 women who underwent cytology, HR-HPV DNA test, hTERC gene amplification test, colposcopy and biopsy. We compared the clinical performance of hTERC gene test along with HR-HPV DNA test of women with colposcopy and routine screening. The samples were histology-confirmed high-grade cervical intraepithelial neoplasia (CIN 2) or worse (CIN2+) as the positive criterion. The test of hTERC gene showed the hTERC gene amplification positivity increased with the severity of histological abnormality and cytological abnormality. The test of hTERC gene showed higher specificity than HR-HPV DNA test for high-grade lesions (84.4% versus 50%) and also higher positive predictive value (90.4% versus 76.5%). Our results predicted that hTERC gene amplification demonstrated more specific performance for predicting the risk of progression and offer a strong potential as a tool for triage in cervical cancer screening, with the limited sensitive as HR-HPV DNA test.

• Journal of Korean Academy of Nursing
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• v.28 no.4
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• pp.1003-1012
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• 1998

The purpose of this research was to identify the effect of human potential seminars on the perceived stigma of adults with epilepsy. The research employed a quasi experimental design and unequivalent control group pre-post design. The test was conducted on 15 adults with epilepsy attending one psychiartric out-patient clinic in Masan City, Korea. The stigma questionnaire was used as a pre-test to these patients. HPS was done ten times for five weeks from May 6, to July 26, 1996. The stigma questionnaire was again given, but this time as a post test. The control group of 14 adults with epilepsy were receiving medication at the same clinic. The human potential seminars were structured by McHolland(1972) and translated by Lee, Hae Seung(1990). The stigma research tool was modified and revised to be appropriate to Korean culture. It consisted of 15 sentences. The internal consistency was 0.92 with Cronbach's α. Research results are as follows. 1) To determine the homogenity of the experimental and control groups, the pre-stigma results were used and democratic-sociologic characteristics, job characteristics and disease related variables were compared. There was no significant difference between the two groups. 2) To identify the relationship between stigma and patient characteristics a pre-test was done. The study used both Mann-Whitney U-test and ANOVA test for statistical analysis. The variables related to stigma were the reason of unemployment and age at onset of epilepsy. 3) The test results of the effect of the human potential seminars on stigma in the patients with epilepsy, showed that stigma in the experimental group was lower than in the control group. The statistical method used to determine the difference between pre and post stigma results was the Wilcoxon signed rank test. The test results were statistically significant at the one percent level. 4) As a follow-up evaluation ten more patients(66.7% of the total) were additionally tested. In order to investigate if the stigmas were different between the pre, post and follow-up, Repeated measure ANOVA was used. The test results showed that the stigma scores were statistically different between the three groups at the one percent level(F=10.06, d.f.=2, p=0.00).

• Biomolecules & Therapeutics
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• v.6 no.1
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• pp.50-55
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• 1998

Antigenic potential of a recombinant human erythropoietin (rhEPO) produced by Dong-A charm. Co. Ltd. was examined by active systemic anaphylaxis (ASA) test in guinea pigs, mouse-rat passive cutaneous anaphylaxis (PCA) reaction and passive hemagglutination (PHA) test. In ASA test, rhEPO induced the signs of restlessness, rubbing or licking nose, sneezing and coughing in the animals immunized with rhEPO 1000 lU/kg alone or rhEPO 1000 lU/kg incorporated into Freund\\\\`s complete adjuvant. In the mouse-rat PCA test, only one of six sera from the animals immunized with rhEPO 1000 lUng incorporated into Alum showed positive result. In the PHA test, rhEPO revealed negative results in all of the rhEPO-immunized groups. From these results, rhEPO was considered to produce IgE in guinea pigs and mice, but not IgG and/or IsM in mice. The results of this study were similar to those of the other recombinant human erythropoietin and these positive results were thought to be caused due to the fact that rhEPO were heterogeneous proteins to guinea pigs and mice. Considering the fact that rhErO has an identical structure with indigenous human erythropoietin, rhEPO is not thought to cause immunological problems in clinical use.