• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.701-707
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• 2016

Indigenous species are needed for more accurate toxicity assessments in tropical regions. Thus, we determined not only the optimum culture conditions for stable maintenance of Nitocra sp. isolated from tropical regions but also the availability of copepods for marine ecotoxicological evaluation. Experiments on temperature, salinity, and diet as factors for optimum culture conditions as well as acute and chronic toxicity tests for ecotoxicological assessment were carried out. Data on optimum culture conditions were analyzed for statistically significant observations using one-way analysis of variance (ANOVA). Optimum temperature and salinity for Nitocra sp. were $29^{\circ}C$ and 24~39‰, and Nitocra sp. fed Tetraselmis suecica had relatively faster development and higher survival than other microalga. Under optimum culture conditions, toxicity tests were carried out. The $LC_{50}$ level and NOEC (no observed effect concentration) levels of copper and arsenic were calculated in the acute toxicity test. In the chronic test of Cu and As, developmental time and survival traits were usable endpoints for toxicity assessments. As a result, tropical copepod Nitocra sp. seems to be a potential candidate organism for marine ecotoxicological evaluation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.595-603
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• 2016

This study was conducted to identify and analyze the educational needs for key vocational competency in nursing students. The participants were 411 nurse students at five universities and the survey was conducted from June 1 to June 31, 2016. The data were analyzed with SPSS WIN 23.0 using descriptive statistics, a paired T-test, Borich's Needs Analysis, as well as the Locus for Focus Model. Based on the results, the subjects recognized the present level of 'professional ethics,' 'self development' and 'interpersonal skills' to be high and those of 'communication skills' and 'skills for understanding groups' to be low. 'Professional ethics,' 'self development,' 'problem solving skills' and 'communication skills' were the most important sub-elements of vocational competency. A significant difference in recognition levels between present and importance ere found in all components of vocational competency. The four priorities were analyzed based on Borich's needs value. In accordance with the Locus for Focus model, 'communication skills,' 'problem solving,' 'resource management skills' and 'self development' were identified as the highest priority sub-factors of vocational competency to nursing students. Based on the result of this study, it is expected to be used as the basic data to develop the nursing student's vocational curriculum and program.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.158-162
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• 2014

Purpose: Reference material (RM) is defined as material that is safe and homogeneous enough about specified characteristic that is made with a purpose of using test of measurement or nominal characteristic. Certified reference material (CRM), which is issued by authorized organization, is defined as reference material that provides characteristic value, link uncertainty and retroactivity. The purpose of this paper was to evaluate recovery of radioimmunoassay by Certified Reference Material enclosed with a certificate and therefore to enhance reliability of test. Materials and Methods: WHO certified reference material is purchased from NIBSC (National Institute for Biological Standard and Control, United Kingdom) and made of 3 levels that are C-1 (low concentration), C-2 (medium concentration) and C-3 (high concentration) and measured for kit at the Seoul National University Hospital. Recovery rate is evaluated after measurement at four different days. Results: Recovery rate results using WHO certified reference material are T4 90%, Ferritin 88%, PSA 94%, Prolactin 99%, AFP 94% and TSH 93%. Conclusion: A procedure that appropriate accuracy, precision, specificity, sensitivity, reproducibility, and validate on the subject of kit for radioimmunoassay is essential. Recovery rate assay as extraction efficiency of analysis process is percent about already measuring results of analysis result after all measuring process. This is very important assessment standards of performance evaluation of immunoassay kit. Recovery rate results of 6 type used WHO CRM are satisfactory to 88~99%. This demonstrates that the radioimmunoassay is a very accurate measurement, which is very effectively utilized in clinical practice.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.503-509
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• 2008

In this study, the daily intake of preservatives in the Korean population was estimated, using data from national health and nutrition studies regarding the concentration of preservatives in each type of food, food intake by sex, age group, and weight. The level of safety of these preservatives was evaluated via comparisons with the acceptable daily intake (ADI) data established by the Joint FAO/WHO expert committee on food additives (JECFA). The Estimated daily intake (EDI) of sorbic acid is 495.85 ${\mu}g$/kg bw, benzoic acid is 215.34 ${\mu}g$/kg bw and parahydroxybenzoate is 5.01 ${\mu}g$/kg bw per day each. Their percentages in relation to ADI are 2, 4.3, and 0.1%, respectively. The comparatively high-consuming groups were taking sorbic acid 1,012.06 ${\mu}g$/kg bw, benzoic acid 229.56 ${\mu}g$/kg bw, and parahydroxybenzoate 11.58 ${\mu}g$/kg bw per day, and their intake levels as a percentage of ADI were 4.1, 4.6, 0.1%, all within safe levels. Males were found to have taken more benzoic acid than women, whereas we detected no sighificant differences in the intakes of sorbic acid and parahydroxybenzoate between males and females. The EDI of sorbic acid, benzoic acid, and parahydroxybenzoate were lower than the ADI in all age groups studied.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.2
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• pp.125-131
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• 2009

Reductive dechlorination of polychlorinated dibenzo-p-dioxins (PCDDs) and its toxicity change were predicted by the linear free energy relationship (LFER) model to assess the zero-valent iron (ZVI) and anaerobic dechlorinating bacteria (ADB) as electron donors in PCDDs dechlorination. Reductive dechlorination of PCDDs involves 256 reactions linking 76 congeners with highly variable toxicities, so is challenging to assess the overall effect of this process on the environmental impact of PCDD contamination. The Gibbs free energies of PCDDs in aqueous solution were updated to density functional theory (DFT) calculation level from thermodynamic results of literatures. All of dechlorination kinetics of PCDDs was evaluated from the linear correlation between the experimental dechlorination kinetics of PCDDs and the calculated thermodynamics of PCDDs. As a result, it was predicted that over 100 years would be taken for the complete dechlorination of octachlorinated dibenzo-p-dioxin (OCDD) to non-chlorinated compound (dibenzo-p-dioxin, DD), and the toxic equivalent quantity (TEQ) of PCDDs could increase to 10 times larger from initial TEQ with the dechlorination process. The results imply that the single reductive dechlorination using ZVI or ADB is not suitable for the treatment strategy of PCDDs contaminated soil, sediment and fly ash. This LFER approach is applicable for the prediction of dechlorination process for organohalogen compounds and for the assessment of electron donating system for treatment strategies.

• 대한공업교육학회지
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• v.40 no.2
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• pp.239-258
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• 2015

The purpose of this study is to provide basic data that can be used in a reasonable assessment of the learning outcomes of STEAM. It presented a learning outcome evaluation method, relative weights of key competencies standard that a learner should cultivate. For this study, a pairwise comparison questionnaire about the key competencies was conducted on the STEAM professionals, and AHP was applied to analyze the priority of main factors of key competencies. The results of this study are as follows. First, the importance of capabilities of convergence accomplishment and capabilities of convergent cognition, in the first layer of key competencies, were 39.4% and 36.8%, respectively. In the education evaluation of the STEAM, capabilities of convergence accomplishment and capabilities of convergent cognition showed similar level of importance, and were considered more important factor than capabilities of convergence attitude (23.8%). Second, the relative importance of capabilities of problem solving (20.0%) was highest in the second layer of key competencies, and followed by capabilities of creative thinking (18.3%), responsibility (15.3%), and understanding convergence knowledge (11.0%). Third, it will be a foundation of a competency evaluation, which reasonably evaluates, based on the relative weights, whether to accomplish educational objectives of the STEAM program In addition, this results is expected to become a guide to develop an education program that can improve the teaching and learning process and raise the learning outcome, as well as an education evaluation of the STEAM.

• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.491-498
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• 2021

In this study, the effective dose was measured using the PCXMC v2.0 program by examining the conditions used to set the diagnostic reference level for intraoral imaging recommended by the government, and the effect of the Al additive filter was confirmed. In oral imaging, the largest effective dose was calculated from the oral mucosa among 11 organs. The effect of the Al additive filter showed an excellent radiation reduction effect at 2mm rather than 1mm. In the case of children aged 5 years, the overall effective dose was calculated to be high in all 11 organs because they are more sensitive to radiation than adults. And as a result of evaluating the image quality according to the use of an additional filter during intraoral imaging, there was no significant difference in SNR and CNR changes compared to before the additional filter was used. Based on this study, it is thought that additional filter settings can be recommended for intraoral imaging.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.403-421
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• 2021

Most of the urban tunnels in Korea, which are represented by the 1st to 3rd subways, use the drainage tunnel by NATM. Recently, when a construction project that actively utilizes large-scale urban space is promoted, negative effects that do not conform to the existing empirical rules of urban tunnels may occur. In particular, there is a high possibility that groundwater fluctuations and hydrodynamic behavior will occur owing to the practice of tunnel technology in Korea, which has mainly applied the drainage tunnel. In order to solve the problem of the drainage tunnel, attempts are being made to control groundwater fluctuations. For this, the establishment of tunnel groundwater management standard concept and the analysis of the tunnel hydraulic behavior were performed. To prevent the problem of groundwater fluctuations caused by the construction of large-scale tunnels in urban areas, it was suggested that the conceptual transformation of the empirical technical practice, which is applied only in the underground safety impact assessment stage, to the direction of controlling the inflow in the tunnel, is required. And the relationship between the groundwater level and the inflow of the tunnel required for setting the allowable inflow when planning the tunnel was derived. The introduction of a tunnel groundwater management concept is expected to help solve problems such as groundwater fluctuations, ground settlement, depletion of groundwater resources, and decline of maintenance performance in various urban deep tunnel construction projects to be promoted in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.147-166
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• 2023

Seed color is controlled by several genes and is a key trait in determining the metabolite content and biological activities of legume genotypes. In this study, 296 adzuki bean accessions, including 159 grey, 99 red, and 38 white adzuki beans, were grown in Korea. Variations in total phenolic content (TPC), total saponin content (TSC), DPPH^• scavenging activity, ABTS^•+ scavenging activity, and ferric reducing antioxidant power (FRAP) were assessed and were reported to be in the ranges of 1.52-8.24 mg GAE/g, 14.36-114.22 mg DE/g, 0.23-12.84 mg AAE/g, 1.05-17.66 mg TE/g, and 0.59-13.14 mg AAE/g, respectively, with a wide variation across adzuki beans. Except for DPPH^• scavenging activity, the average values declined in the order gray > red > white adzuki beans, each demonstrating a significant variation (p < 0.05). White adzuki beans, which showed low metabolite content and antioxidant activity, were clearly separated from the gray and red genotypes using principal component and hierarchical cluster analyses. Moreover, TPC, TSC, and antioxidant activities were strongly correlated, regardless of seed color. Overall, the diversity of the TPC, TSC, and antioxidant activity in a broad population of adzuki bean genotypes was determined. Furthermore, this study found that seed color variation in adzuki beans had a significant effect on the metabolite content and antioxidant activity. Superior accessions with high levels of TPC, TSC, and antioxidant activity were also discovered and could be used for functional plant breeding and human consumption. The findings of this study may be useful for understanding the relationship between seed coat color and metabolite concentration in adzuki beans, paving the way for molecular-level analyses.

• Journal of the Korea Institute of Building Construction
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• v.23 no.5
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• pp.607-618
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• 2023

Pervasive research underscores the direct correlation between an enhanced safety climate and a marked reduction in accidents. The intricacies of safety climate are governed by three pivotal strata: organizational management, on-site operations, and the broader enterprise framework. Within an organizational context, sustaining optimal performance across these layers poses a considerable challenge, often attributable to the constraints of available managerial bandwidth. It becomes imperative, then, to conceive a phased enhancement blueprint for the safety climate. To orchestrate this blueprint with precision, a discerning understanding of the hierarchy of safety climate metrics is essential, which subsequently guides judicious managerial resource allocation. This investigation is anchored in elucidating the hierarchical significance of safety climate metrics through the Analytical Hierarchy Process(AHP). Implementing the AHP framework, both a questionnaire was disseminated and a subsequent analysis undertaken, culminating in the extraction of relative priorities of safety climate determinants. Consequent to this analysis, "workers' safety prioritization and risk aversion" emerged as the foremost dimension, holding a significance weight of 0.1900. Furthermore, within the detailed elements, "unwavering adherence to safety mandates amidst demanding operational constraints" ranked supreme, manifesting a weight of 0.6663. The findings encapsulated in this study are poised to be foundational in sculpting improvements at an institutional level and devising policies, all with the end goal of fostering an exemplar safety climate within construction arenas.