• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.10
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• pp.61-70
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• 1999

In this paper, we analyze several exposure time schedules to obtain uniform multiple hologram and measure the diffraction efficiencies of holograms stored in $LiNbO_3$:Fe(0.015wt%) crystal through experiments. The minimum angular selectivity and the intensity ration of two incident beams are investigated precisely by the high resolution system(minimum angle : $0.0028^{\circ}$). Considering initial recording time, total exposure time and time constants, the efficiency distribution(0.014 ${\pm}$ 0.005%) of 100 holograms is measured and the 330 analog images are recorded in the same place. Also, total 500 holograms are retrieved by spatial multiplexing.

• Journal of radiological science and technology
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• v.5 no.1
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• pp.15-19
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• 1982

Authors made an experiment to know the relation of surface doses and multiple factors of exposure by using grids, fields, tube voltages objects and distances and obtained the results as follows: 1. Surface doses were increased in proportion to the thickness of objects. 2. Surface doses were more influenced when irradiated fields were small and tube voltages were low. 3. Surface doses were a logarthmic proportion to the focus-object distance. 4. Multiple factors of exposure by using grid were under the control of the thickness of objects, irradiated fields and tube voltages but the relation of them were not fixed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.04b
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• pp.132-135
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• 2002

In this paper, a new method to implement the photopolymer-based VHOE using the optimized exposure time schedule is proposed. The cumulative grating strength dependence on the exposure energy is mathematically modeled by using the fourth-order polynomial function and then using this model, the optimized exposure-time schedule of the photopolymer for recording the given multiple gratings is calculated.

• Molecular & Cellular Toxicology
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• v.4 no.4
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• pp.360-365
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• 2008

In the last several years, studies on the association of oxidative stress damage with exposure in the work place have been conducted. Xenobiotics create an imbalance of the homeostasis between oxidant molecules and antioxidant defense. By monitoring oxidative stress biomarkers, information was obtained on damages induced by oxidative stress and the toxicity of xenobiotics. In the present study, a Job Exposure Matrix (JEM) was constructed using the data from the Working Environment Measurement (WEM) of painters in the shipyard industry from the past 3 years to assess the exposure status. Additionally, by measuring the concentration of urinary malondialdehyde (MDA), the effect of lipid peroxidation was examined. The subjects consisted of 68 workers who were exposed to mixed organic solvents in the painting process and 25 non-exposure controls. The exposure indices of the exposure groups were significantly different (sprayer: 0.83, touchup: 0.54, assistant: 0.13, P<0.05). The urinary MDA concentration of the exposure group was 48.60${\pm}$ 39.23 ${\mu}mol$/mol creatinine, which was significantly higher than 18.03${\pm}$16.33 ${\mu}mol$/mol creatinine of the control group (P<0.05). From the multiple regression analysis of urinary MDA, the regression coefficient for exposure grade was statistically significant. In future studies, evaluation of the antioxidant levels of subjects should be performed simultaneously with quantitative exposure measurements.

• Korean Journal of Occupational Health Nursing
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• v.28 no.4
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• pp.285-292
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• 2019

Purpose: This study aimed to examine the factors associated with behavior that reduces exposure to environmental hormones among nursing students. Methods: Data were collected from 160 nursing students in D and B cities, using self-report questionnaires. Data were analyzed using SPSS 22.0, and the analyses included descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient test, and stepwise multiple regression. Results: Behavior that reduces exposure to environmental hormones differed significantly in terms of the participants' knowledge about environmental hormones. Behavior that reduces exposure to environmental hormones was negatively correlated with knowledge of environmental hormones, attitude towards pro-environmental behavior, and environmental self-efficacy; these factors were significant predictors of behavior that reduces exposure to environmental hormones, and accounted for 27.0% of the variance. Conclusion: Environmental self-efficacy was identified as the most significant factor affecting behavior that reduces exposure to environmental hormones in nursing students. Therefore, it is necessary to develop programs to improve pro-environmental behavior and environmental self-efficacy in nursing students.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.9
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• pp.3322-3347
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• 2021

Cloud Storage is the primary component of many businesses on cloud. Majority of the enterprises today are adopting a multicloud strategy to keep away from vendor lock-in and to optimize cost. Auditing schemes are used to ascertain the integrity of cloud data. Of these schemes, only the Provable Data Possession schemes (PDP) are resilient to key-exposure. These PDP schemes are devised using Public Key Infrastructure (PKI-) based cryptography, Identity-based cryptography, etc. PKI-based systems suffer from certificate-related communication/computational complexities. The Identity-based schemes deal with the exposure of only the auditing secret key (audit key). But with the exposure of both the audit key and the secret key used to update the audit key, the auditing process itself becomes a complete failure. So, an Identity-based PDP scheme with Parallel Key-Insulation is proposed for multiple cloud storage. It reduces the risk of exposure of both the audit key and the secret key used to update the audit key. It preserves the data privacy from the Third Party Auditor, secure against malicious Cloud Service Providers and facilitates batch auditing. The resilience to key-exposure is proved using the CDH assumption. Compared to the existing Identity-based multicloud schemes, it is efficient in integrity verification.

• Journal of Microbiology and Biotechnology
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• v.21 no.6
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• pp.646-651
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• 2011

Cultures of Saccharomyces cerevisiae were treated with pulsed electric fields to improve accumulation of zinc in the biomass. Under optimized conditions, that is, on 15 min exposure of the 20 h grown culture to PEFs of 1500 V and 10 ${\mu}s$ pulse width, accumulation of zinc in the yeast biomass reached a maximum of 15.57 mg/g d.m. Under optimum zinc concentration (100 ${\mu}g$/ml nutrient medium), its accumulation in the cells was higher by 63% in comparison with the control (without PEFs). That accumulation significantly correlated against zinc concentration in the medium. Neither multiple exposure of the cultures to PEFs nor intermittent supplementation of the cultures with zinc increased the zinc accumulation. The intermittent supplementation of the cultures with zinc and multiple exposures on PEFs could even reduce the accumulation efficiency, respectively, by 57% and 47%.

• Journal of the Korean Home Economics Association
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• v.33 no.4
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• pp.11-23
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• 1995

The purpose of this study is to investigate some influencing factors related to the urban housewives' homemanagement and management behavior on the problems of the environment. Questionaire Survey method was used and the sample was taken from 490 housewives who lives in Seoul and has husband and more than one child. The Research for this study was operated by frequency, mean, percentage, Factor Analysis, t-test, ANOVA, Duncan's multiple range test, and multiple regression analysis through the SAS program package. Based on the findings of this study, housewives' value, degree of exposure to mass communications, housewives' level of education were most influencial variables on Housewives' home management behavior pattern. And Housewives' home management behavior pattern, degree of exposure to mass communications, housewives' age, knowledge of the problems of the environment were most influencial variables on Housewives' management behavior onthe problesm of the environment.

• 대한예방의학회:학술대회논문집
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• 1994.02a
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• pp.651-657
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• 1994

To assess quantitatively the association between benzene exposure and leukemia, we examined the mortality rate of a cohort with occupational exposure to benzene. Cumulative exposure for each cohort member was estimated from historical air-sampling data and, when no sampling data existed, from interpolation on the basis of existing data. The overall standardized mortality ratio (a measure of relative risk multiplied by 100) for leukemia was 337 (95 percent confidence interval, 154 to 641), and that for multiple myeloma was 409 (95 percent confidence interval, 110 to 1047). With stratification according to levels of cumulative exposure, the standardized mortality ratios for leukemia increased from 109 to 322, 1186, and 6637 with increases in cumulative benzene exposure from less than 40 parts per million-years (ppm-years), to 40 to 199, 200 to 399, and 400 or more. respectively. A cumulative benzene exposure of 400 ppm years is equivalent to a mean annual exposure of 10 ppm over a 40-year working lifetime; 10 ppm is the currently enforceable standard in the United States for occupational exposure to benzene. To examine the shape of the exposure-response relation, we performed a conditional logistic-regression analysis, in which 10 controls were matched to each cohort member with leukemia. From this model, it can be calculated that protection from benzene induced leukemia would increase exponentially with any reduction in the permissible exposure limit.

• Journal of Korean society of Dental Hygiene
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• v.10 no.4
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• pp.717-725
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• 2010

Objectives : This study was to determine the level of occupational exposure and quality of life and to investigate the effect of variables related occupational exposure on quality of life in dental hygienists. Methods : A survey questionnaire was mailed to dental hygienists from April 4 to May 15, 2010. The subjects were 256(56.9%), who were worked in dental hospital and clinic with mean age of $29.59{\pm}7.30$. Quality of life was measured using the WHOQOL-BREF. It consists of 26 items, each with 5-point likert scale. Self control of occupational exposure was measured using the 3-items. The data were analyzed with chi-square, t-test, one-way ANOVA, pearson correlation coefficients and multiple regression using the SPSS WIN 17.0 program. Results : Regarding quality of life, the subjects was a mean of 90.73 out of a maximum 130 points. The level of self control occupational exposure a mean of 3.20 out of a maximum 5 points. Self control of occupational exposure, frequency of panorama radiography, work experience of radiography had a significant impact on quality of life in dental hygienists. Conclusions : Based on the findings, occupational exposure is negatively associated with quality of life in dental hygienists. These results suggest that health promotion program should be considered various factors related occupational exposure in dental hygienists.