• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.2
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• pp.78-90
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• 2016

This report is to introduce detail processes during the restoration/revision project for the Korean Standard Methods for Marine Environment. The processes are composed of 3 steps: questionaries, QA/QC confirming step by CRM(Certified Reference Materials), and advisory council by specialists. The questionaries required four main topics to be included to the restoration/revision protocol: 1. the guidelines to sampling, transportation, storage, and pre-analytical procedures for the marine specimens, 2. the unified analytical method, especially for the organic compounds, 3. the QA/QC test requirement for CRM, 4. introduction of diverse analytical instruments, 5. the customer- friendly express of the protocol. Based on these new protocol, we expect two most important effects: 1, increased insurance of international credibility and equivalence by the QA/QC procedures, 2. increased conformability and representatively from wide-spread use of the protocol. Finally we suggested several residual topics remained to the inter-government cooperation.

• Korean Journal of Radiology
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• v.24 no.4
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• pp.284-293
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• 2023

Objective: To validate a simplified ordinal scoring method, referred to as modified length-based grading, for assessing coronary artery calcium (CAC) severity on non-electrocardiogram (ECG)-gated chest computed tomography (CT). Materials and Methods: This retrospective study enrolled 120 patients (mean age ± standard deviation [SD], 63.1 ± 14.5 years; male, 64) who underwent both non-ECG-gated chest CT and ECG-gated cardiac CT between January 2011 and December 2021. Six radiologists independently assessed CAC severity on chest CT using two scoring methods (visual assessment and modified length-based grading) and categorized the results as none, mild, moderate, or severe. The CAC category on cardiac CT assessed using the Agatston score was used as the reference standard. Agreement among the six observers for CAC category classification was assessed using Fleiss kappa statistics. Agreement between CAC categories on chest CT obtained using either method and the Agatston score categories on cardiac CT was assessed using Cohen's kappa. The time taken to evaluate CAC grading was compared between the observers and two grading methods. Results: For differentiation of the four CAC categories, interobserver agreement was moderate for visual assessment (Fleiss kappa, 0.553 [95% confidence interval {CI}: 0.496-0.610]) and good for modified length-based grading (Fleiss kappa, 0.695 [95% CI: 0.636-0.754]). The modified length-based grading demonstrated better agreement with the reference standard categorization with cardiac CT than visual assessment (Cohen's kappa, 0.565 [95% CI: 0.511-0.619 for visual assessment vs. 0.695 [95% CI: 0.638-0.752] for modified length-based grading). The overall time for evaluating CAC grading was slightly shorter in visual assessment (mean ± SD, 41.8 ± 38.9 s) than in modified length-based grading (43.5 ± 33.2 s) (P < 0.001). Conclusion: The modified length-based grading worked well for evaluating CAC on non-ECG-gated chest CT with better interobserver agreement and agreement with cardiac CT than visual assessment.

• Korean Journal of Radiology
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• v.24 no.11
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• pp.1093-1101
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• 2023

Objective: Cine magnetic resonance imaging (MRI) has emerged as a noninvasive method to quantitatively assess bowel motility. However, its accuracy in measuring various degrees of small bowel motility has not been extensively evaluated. We aimed to draw a quantitative small bowel motility score from cine MRI and evaluate its performance in a population with varying degrees of small bowel motility. Materials and Methods: A total of 174 participants (28.5 ± 7.6 years; 135 males) underwent a 22-second-long cine MRI sequence (2-dimensional balanced turbo-field echo; 0.5 seconds per image) approximately 5 minutes after being intravenously administered 10 mg of scopolamine-N-butyl bromide to deliberately create diverse degrees of small bowel motility. In a manually segmented area of the small bowel, motility was automatically quantified using a nonrigid registration and calculated as a quantitative motility score. The mean value (MV) of motility grades visually assessed by two radiologists was used as a reference standard. The quantitative motility score's correlation (Spearman's ρ) with the reference standard and performance (area under the receiver operating characteristics curve [AUROC], sensitivity, and specificity) for diagnosing adynamic small bowel (MV of 1) were evaluated. Results: For the MV of the quantitative motility scores at grades 1, 1.5, 2, 2.5, and 3, the mean ± standard deviation values were 0.019 ± 0.003, 0.027 ± 0.010, 0.033 ± 0.008, 0.032 ± 0.009, and 0.043 ± 0.013, respectively. There was a significant positive correlation between the quantitative motility score and the MV (ρ = 0.531, P < 0.001). The AUROC value for diagnosing a MV of 1 (i.e., adynamic small bowel) was 0.953 (95% confidence interval, 0.923-0.984). Moreover, the optimal cutoff for the quantitative motility score was 0.024, with a sensitivity of 100% (15/15) and specificity of 89.9% (143/159). Conclusion: The quantitative motility score calculated from a cine MRI enables diagnosis of an adynamic small bowel, and potentially discerns various degrees of bowel motility.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.76-79
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• 2013

Purpose: It is very important to establish the appropriate reference range in the laboratory for preventing mistakes like false positive or false negative. Because the reference range in the laboratory is standard of patient test results interpretation. Proinsulin is precursor hormone of insulin, and the importance is increasing for diagnosing diabetes or insulinoma. Proinsulin reagent used in our laboratory is produced in the USA, and the reference range provided by manufacturer was adapted to our reference range after the validation test. But, it is generally recommend for the every laboratory to establish the their own reference range. So, we decided to re-evaluate the reference range with our patients' test results. Materials and Methods: Among 737 patients who had been to health promotion center in our hospital between Dec. $8^{th}$ 2011 and Dec. $21^{st}$ 2011, 563 patients are chosen with exception of diabetics patients and patients showing abnormal test results in Fasting Glucose, HbA1c, Insulin, and C-peptide. The 563 test results (275 males and 288 females) were classified with three groups(entire, male, female), and analysis of normal distribution was performed with aid of SPSS(version 19.0). Because Each group didn't show normal distribution, the reference range was set from the lowest limit of 2.5% to the highest limit of 97.5% with Percentile method used in non-normal distribution. Results: When evaluation values are sorted in ascending order, the entire range is 4.5~52.0 pM and 5.3~51.9 pM for male and 4.5~52.0 pM for female. The calculated reference range with percentile method shows 6.7~26.5 pM for entire group, 6.8~26.5 pM for male and 6.7~26.5 pM for female, respectively. Conclusion: The reference range provided by reagent manufacturer is 6.4~9.4 pM and the one established in this study is 6.7~26.5 pM. This difference might be caused by racial characteristics between Western people and Koreans. So an ideal reference range can be gotten with normal population visiting to every hospital. Our hospital has been using the newly re-establishing reference range under consultation with the department of endocrinology since Aug. $1^{st}$ 2012.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.2
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• pp.140-146
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• 2008

Marine ecotoxicological standard method using fish larvae was established with the standard test species of Oryzias latipes(Japanese Medaka) and Paralichthys olivaceus(flounder) and with the 7 day $LC_{50}$ as endpoint. Test method referred to the USEPA(1994) with the replacement of test species found in the Korean water. Standard test species were selected in terms of the species supply and ecological importance in Korean waters. Japanese medaka can be reared with small tanks in the lab and has wide tolerance on salinity, and flounder eggs can be easily obtained from commercial fish hatcheries. General conditions for larval fish toxicity test are as follows. The possible salinity ranges for toxicity test were $0{\sim}35\;psu$ for medaka and >20 psu for flounder. Test type was designated as static non-renewal test if the dissolved oxygen in the test chamber does not fall below 4.0 mg/L. Ages of test species were selected as 7 days after hatched for medaka(about 5 mm TL) and 25 days for flounder(about 10 mm TL) because of the low natural mortality after these periods. Test can be accepted when the survival rates are over 80% in control. Also, species sensitivity on standard reference materials(copper, cadmium or zinc) must be provided with the toxicity test results.

• Journal of the Korean Institute of Gas
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• v.25 no.6
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• pp.66-73
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• 2021

In this study, The full load test and WHTC mode test were performed to examine the effect on a heavy duty natural gas engine according to the type of standard gas for certification to check engine performance and exhaust characteristics. Two types of standard gas (G_r, G₂₃) and commercially available natural gas were applied as the fuel used. As a result of the test results of three natural gases with different fuel compositions, G₂₃ with a high nitrogen content was inferior in torque, fuel consumption, and thermal efficiency conditions. In addition, when evaluated in the WHTC mode it was possible to obtain a result that satisfies the EURO VI regulation. However, compared to the other two fuels, the emission characteristics of G₂₃ decreased CO2 and CO, but increased CH4, NOx and PN emissions.

• Journal of Fashion Business
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• v.24 no.2
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• pp.32-43
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• 2020

The purpose of this study is to analyze the granny look of the new-tro trend via Alessandro Michele's Gucci collection and to provide a reference standard for future design developments by identifying the representation of the granny look. To analyze the new-tro trend and the granny look, basic concepts were analyzed through aesthetic and art books and the photographic data were collected through Internet sites. A total of 186 fashion images were considered as granny look by five clothing experts. The images were subdivided into silhouettes and items, materials, patterns, and colors to analyze the modeling factors and identify the intrinsic inner meaning based on the theory of Nostalgia. The analysis showed that the silhouette was expressed naturally without exaggeration or shrinkage. The thermosetting materials included fur, velvet, knit and quilted materials, while the colors showed raw and faded shades based on the use of natural colors. The patterns were mostly natural, such as flowers, leaves, and stalks, which were aimed at nature. The inner meaning of the granny look is based on the theory of Nostalgia, primarily because it is an emotional fairy tale and second, it reflected the sessions of nature. Also, it is a reinterpretation of the narrative. In conclusion, the academic and fashion industries need to understand the various emerging trends in accordance with the social and cultural backgrounds to derive a positive benefit.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.6
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• pp.82-89
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• 2014

The purpose of this study is to propose a simple model to evaluate the compressive strength development of concrete with various supplementary cementitious materials (SCMs) and cured under different temperatures. For the generalization of the model, the ACI 209 parabola equation was modified based on the maturity function and then experimental constants A and B and 28-day compressive strength were determined from the regression analysis using a total of 265 data-sets compiled from the available literature. To verify the proposed model, concrete specimens classified into 3 Groups were prepared according to the SCM level as a partial replacement of cement and curing temperature. The analysis of existing data clearly revealed that the 28-day compressive strength decreases when the curing temperature is higher and/or lower than the reference curing temperature ($20^{\circ}C$). Furthermore, test results showed that the compressive strength development of concrete cured under $20^{\circ}C$ until an early age of 3 days was marginally affected by the curing temperature afterward. The proposed model accurately predicts the compressive strength development of concrete tested, indicating that the mean and standard deviation of the ratios between predictions and experiments are 1.00 and 0.08, respectively.

• Journal of Environmental Health Sciences
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• v.35 no.5
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• pp.402-410
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• 2009

This study was carried out to examine the optimal analytical method for determination of urinary toxic arsenic (inorganic arsenic and its metabolites) by HG-AAS (hydride generation-atomic absorption spectrometry). In the analysis of SRMs (standard reference materials), method E (addition of 0.4% L-cysteine to pre-reductant and use 0.04M HCl as carrier acid) showed the most accurate results compared with the reference values. In the analysis of 30 urinary samples, analytical results were significantly different depend on the component of pre-reductant and the concentration of carrier acid. When the concentration of carrier acid was higher, the analytical result was lower. The recovery rates of MMA (monomethylarsonic acid) and DMA (dimethylarsenic acid) were varied by the concentration of pre-treatment acid and carrier acid and hydride generation reagents. When the concentration of carrier acid was 1.62 M (5% HCl), the recovery rates of DMA was 1%. The recovery rates of MMA and DMA in method E (=V) were 102% and 100%, respectively. The results of this study suggest that the component and concentration of pre-reductant and carrier acid must be carefully adjusted in the analysis of urinary arsenic, and method E is recommendable as the most precise analytical method for determination of urinary toxic arsenic.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.1
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• pp.43-48
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• 2011

Introduction: This study examined the anatomical morphology of the medial surface of the posterior mandible using 3-dimensional cone-beam computed tomography (CT) images to reduce the number of complications related to dental implant placement. Materials and Methods: Fifty patients were enrolled in this study with an average age (${\pm}$standard deviation) of 44.28 (${\pm}13.05$). On the coronal views cone-beam CT of the first molars, the distance between the top of the canal and alveolar crest vertical distance (VD), the distance between the upper-most point of the canal and the point perpendicular to the lingual cortical margin of the mandible lingual distance (LD), the location of the starting point of VD for reducing from the vertical reference line (VD point), and the inclination of the mandibular medial surface (lingual inclination) were measured, and a statistical evaluation was performed using SPSS for Windows version 15.0. Results: The mean VD0 was $16.91{\pm}2.47\;mm$ and VDx decreased with increasing x value. The mean LD was $5.27{\pm}1.36\;mm$. The VD began to decrease at the mean location of $6.12{\pm}0.96\;mm$ from the vertical reference line. The mean lingual inclination was $1.52{\pm}0.72^{\circ}$. Conclusion: These results will assist in the accurate placement of dental implants and the reduction of complications, particularly in the case of preoperative implant planning using only 2-dimensional imaging methods. (ex. panoramic radiography)