• The Journal of Advanced Prosthodontics
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• v.14 no.5
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• pp.294-304
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• 2022

PURPOSE. The purpose of this study was to evaluate the influence of different palatal vault configurations on the accuracy and scan speed of intraoral scans (IO) of completely edentulous arches. MATERIALS AND METHODS. Three different virtual models of a completely edentulous maxillary arch with different palatal vault heights- Cl I moderate (U-shaped), Cl II deep (steep) and Cl III shallow (flat)-were digitally designed using CAD software (Meshmixer; Autodesk, USA) and 3D-printed using SLA-based 3D-printer (XFAB; DWS, Italy) (n = 30; 10 specimens per group). Each model was scanned using intraoral scanner (Trios 3; 3Shape^TM, Denmark). Scanning time was recorded for all samples. Scanning accuracy (trueness and precision) were evaluated using digital subtraction technique using Geomagic Control X v2020 (Geomagic; 3DSystems, USA). One-way analysis of variance (ANOVA) test was used to detect differences in scanning time, trueness and precision among the test groups. Statistical significance was set at α = .05. RESULTS. The scan process could not be completed for Class II group and manufacturer's recommended technique had to be modified. ANOVA revealed no statistically significant difference in trueness and precision values among the test groups (P=.959 and P=.658, respectively). Deep palatal vault (Cl II) showed significantly longer scan time compared to Cl I and III. CONCLUSION. The selection of scan protocol in complex cases such as deep palatal vault is of utmost importance. The modified, adopted longer path scan protocol of deep vault cases resulted in increased scan time when compared to the other two groups.

• Communications for Statistical Applications and Methods
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• v.30 no.1
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• pp.95-107
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• 2023

Purpose: The statistical analysis of point processes on linear networks is a recent area of research that studies processes of events happening randomly in space (or space-time) but with locations limited to reside on a linear network. For example, traffic accidents happen at random places that are limited to lying on a network of streets. This paper applies techniques developed for point processes on linear networks and the tools available in the R-package spatstat to estimate the intensity of traffic accidents in Leon County, Florida. Methods: The intensity of accidents on the linear network of streets is estimated using log-linear Poisson models which incorporate cubic basis spline (B-spline) terms which are functions of the x and y coordinates. The splines used equally-spaced knots. Ten different models are fit to the data using a variety of covariates. The models are compared with each other using an analysis of deviance for nested models. Results: We found all covariates contributed significantly to the model. AIC and BIC were used to select 9 as the number of knots. Additionally, covariates have different effects such as increasing the speed limit would decrease traffic accident intensity by 0.9794 but increasing the number of lanes would result in an increase in the intensity of traffic accidents by 1.086. Conclusion: Our analysis shows that if other conditions are held fixed, the number of accidents actually decreases on roads with higher speed limits. The software we currently use allows our models to contain only spatial covariates and does not permit the use of temporal or space-time covariates. We would like to extend our models to include such covariates which would allow us to include weather conditions or the presence of special events (football games or concerts) as covariates.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.174-178
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• 1981

The experiment was dealt with an investigations on the agronomic potential of primary octraploid triticale in comparion with Chokwang, a major common wheat, local rye cultivar and new triticale selection Suweon #1 and Suweon #2. This octaploid triticale was originated from the cross of Jukoku #81 x Local rye cultivar. The results obtained were summarized as follows; Cold tolerance of the P-Tcl was better than those of the wheat cultivar Chokwang, triticale varieties Suweon #1 and Suweon #2, and comparable to local rye. Culm length of P-Tel was 113cm that was intermediate between the wheat and rye, and its culm thickness was thiner than the checks except the rye. Lateness of heading and maturing date of the P-Tel seemed to be over-dominant. However, flowering date after heading was 3 to 7 days earlier than the Suweon #1 and Suweon #2. Yield potential of the P-Tel was poor in comparision with the triticale cultivar Suweon #1 and Suweon #2 which was attributed to the low fertility and less number of the heads per squ are meter. If it was . improved the low fertility and less number of the valid tillers through the cross with the good secondary triticale it seemed to be an useful material for triticale breeding, expecially for improving cold tolerant winter triticale varieties in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.195-200
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• 1985

This experiment was carried out to know the processes of protoplast isolation, culture and plant regeneration in aims of introducing foreign genes into plant cells through plant gene vector, and cellular selection for plant improvement. The main results indicated that 2% cellulase plus 0.5% macerozyme is proper for isolation of protoplasts from leaf mesophyll cells of N. plumbaginifolia, plating efficiency was higher in 1.4-2.0 x 10$^4$ cells/ml, complete cell wall was regenerated after 2 days culture, cell division and cell mass were observed after 4 days and 2 weeks, respectively, colony was developed after 3 weeks culture, addition of 1-2mg/l BA promoted shoot differentiation while root differentiation did not required hormone and seeds were harvested from more than 100 cell lines for further investigation and study.

• Computers and Concrete
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• v.31 no.2
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• pp.85-95
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• 2023

Natural pozzolans are used as additives in cement to develop more durable and high-performance concrete. Pozzolanic activity index (PAI) is important for assessing the performance of a pozzolan as a binding material and has an important effect on the compressive strength, permeability, and chemical durability of concrete mixtures. However, the determining of the 28 days (short term) and 90 days (long term) PAI of concrete mixtures is a time-consuming process. In this study, to reduce extensive experimental work, it is aimed to predict the short term and long term PAIs as a function of the chemical compositions of various natural pozzolans. For this purpose, the chemical compositions of various natural pozzolans from Central Anatolia were determined with X-ray fluorescence spectroscopy. The mortar samples were prepared with the natural pozzolans and then, the short term and the long term PAIs were calculated based on compressive strength method. The effect of the natural pozzolans' chemical compositions on the short term and the long term PAIs were evaluated and the PAIs were predicted by using multiple linear regression (MLR) and adaptive neuro-fuzzy inference system (ANFIS) model. The prediction model results show that both reactive SiO₂ and SiO₂+Al₂O₃+Fe₂O₃ contents are the most effective parameters on PAI. According to the performance of prediction models determined with metrics such as root mean squared error (RMSE) and coefficient of correlation (R²), ANFIS models are more feasible than the multiple regression model in predicting the 28 days and 90 days pozzolanic activity. Estimation of PAIs based on the chemical component of natural pozzolana with high-performance prediction models is going to make an important contribution to material engineering applications in terms of selection of favorable natural pozzolana and saving time from tedious test processes.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.259-259
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• 2022

Soil salinity is a major factor that reduces crop yields. The amount of soil affected by salinity is about 83 million hectares (FAO 2000), which is increasing due to the effects of climate change. In soybean [Glycine max (L.) Merr.], nutritional properties such as protein, starch, and sucrose content together with biomass and yield tends to reduce due to excessive salt. As a result of QTL mapping using the 169 F_2:3 population from the KA-1285 (salt-tolerant) × Daepung (salt-sensitive) in a previous study, two major QTLs (Gm03_39796778 and Gm03_40600088) related to salt tolerance were found on chromosome 3. In this study, the CDS region of the Gmsalt3 gene was analyzed using the ABI 3730x1 DNA Analyzer (Macrogen, Korea). The sequence of Gmsalt3 gene in KA-1285 was compared with Williams 82.a4.vl and PI483463 (Glycine soja). Two transversions were found at exon6 in KA-1285 and PI483463. Currently, whole genome sequencing and variation analysis using the Illumine Novaseq 6000 machine (Illumina, USA) are in progress. The results of this study can provide useful molecular markers for the selection of salt-tolerant soybeans and can be used as basic data for future salt-tolerant gene research.

• Journal of the Korea Fashion and Costume Design Association
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• v.25 no.3
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• pp.1-16
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• 2023

The purposes of this study were to investigate bag purchasing behaviors and design preferences of male and female adult consumers, and to find the differences depending on sex and age variable. A survey was conducted on 400 male and female adults from 20s to 50s. The questionnaire consisted of bag purchase behaviors, bag design preferences, and the subjects' demographic characteristics. The data were analyzed by Cronbach's α, factor analysis, x² test and t-test using SPSS. The results were as follows. First, as bag selection criteria, four factors (practicality, symbolism, aesthetics, and economics) were derived, and adult consumers considered economics as the most important among the factors. As for purchasing information sources, three factors (media, human resources, and store) were derived, and adult consumers considered human resources and store information sources more important than media. The main motive for purchasing bags was age and damage of the owned products, and Internet shopping malls were the most common purchasing place. The average annual cost of purchasing bags was 100,000 to 300,000 won, and the frequency of purchase was about once a year. Second, as bag preference images, four factors (individual, romantic, active, and classic image) were derived, and adult consumers preferred classic images the most. The shoulder bag was the most preferred as the bag shape, and black was the most preferred bag color. For the material, natural leather was the most preferred, and for the size, medium size was the most preferred. Third, bag purchasing behaviors and design preferences showed many significant differences according to the sex and age of the consumers. Therefore, the results of this study suggests that bag companies need to establish product development and marketing strategies in consideration of differences according to the sex and age group of adult consumers.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.175-187
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• 2023

Peanuts, also known as groundnuts (Arachis hypogaea L.), are globally recognized as a vital oilseed crop. Peanuts are rich in proteins (e.g., arginine), oils (e.g., oleic acid and linoleic acid), fiber, vitamins (e.g., niacin and tocopherol), and carbohydrates and are consumed worldwide. However, the presence of aflatoxin (AF) has garnered substantial attention since its initial discovery as the causative agent of Tukey's X disease in the United Kingdom in 1960. Among the 18 aflatoxins identified, aflatoxin B₁ (AFB₁) has the highest toxic activity and causes hepatocellular carcinoma. It is classified as Group I by the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO). The present study was conducted to evaluate aflatoxin B₁ resistance of 102 peanut accessions and select putative aflatoxin B₁-resistant peanut accessions to aflatoxin B₁. One hundred and one Korean germplasms harvested in 2020 were inoculated with A. flavus to identify aflatoxin-resistant cultivars, and the aflatoxin B₁ concentration was measured using an ultra-performance liquid chromatography-photodiode array detector. Twenty-six accessions with aflatoxin B₁ concentrations lower than those of the check plant 55-437 were chosen for the development of aflatoxin-resistant varieties in Korea. As Korean aflatoxin-resistant varieties have not yet been developed, the findings of the present study are expected to provide useful information for the development of aflatoxin-resistant cultivars.

• Korean Journal of Radiology
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• v.22 no.1
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• pp.63-71
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• 2021

Objective: To identify the CT findings associated with treatment failure after antibiotic therapy for acute appendicitis. Materials and Methods: Altogether, 198 patients who received antibiotic therapy for appendicitis were identified by searching the hospital's surgery database. Selection criteria for antibiotic therapy were uncomplicated appendicitis with an appendiceal diameter equal to or less than 11 mm. The 86 patients included in the study were divided into a treatment success group and a treatment failure group. Treatment failure was defined as a resistance to antibiotic therapy or recurrent appendicitis during a 1-year follow-up period. Two radiologists independently evaluated the following CT findings: appendix-location, involved extent, maximal diameter, thickness, wall enhancement, focal wall defect, periappendiceal fat infiltration, and so on. For the quantitative analysis, two readers independently measured the CT values at the least attenuated wall of the appendix by drawing a round region of interest on the enhanced CT (HU_post) and non-enhanced CT (HU_pre). The degree of appendiceal wall enhancement (HU_sub) was calculated as the subtracted value between HU_post and HU_pre. A logistic regression analysis was used to identify the CT findings associated with treatment failure. Results: Sixty-four of 86 (74.4%) patients were successfully treated with antibiotic therapy, with treatment failure occurring in the remaining 22 (25.5%). The treatment failure group showed a higher frequency of hypoenhancement of the appendiceal wall than the success group (31.8% vs. 7.8%; p = 0.005). Upon quantitative analysis, both HU_post (46.7 ± 21.3 HU vs. 58.9 ± 22.0 HU; p = 0.027) and HU_sub (26.9 ± 17.3 HU vs. 35.4 ± 16.6 HU; p = 0.042) values were significantly lower in the treatment failure group than in the success group. Conclusion: Hypoenhancement of the appendiceal wall was significantly associated with treatment failure after antibiotic therapy for acute appendicitis.

• The Korean Journal of Nuclear Medicine Technology
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• v.19 no.2
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• pp.55-62
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• 2015

Purpose Various methods for reducing radiation exposure have been continuously being developed. The aim of this study is to evaluate effectiveness of dose reduction, image quality and PET SUV changes by applying combination of automatic exposure dose(AEC), automated dose-optimized selection of X-ray tube voltage(CAREkV) and sinogram affirmed iterative reconstruction(SAFIRE) which can be controled by user. Materials and Methods Torso, AAPM CT performance and IEC body phantom images were acquired using biograph mCT64, (Siemens, Germany) PET/CT scanner. Standard CT condition was 120 kV, 40 mAs. Radiation exposure and noise were evaluated by applying AEC, CAREkV(120 kV, 40 mAs) and SAFIRE(120 kV, 25 mAs) with torso phantom compare to standard CT condition. And torso, AAPM and IEC phantom images were acquired with combination of 3 methods in condition of 120 kV, 25 mAs to evaluate radiation exposure, noise, spatial resolution and SUV changes. Results When applying AEC, CTDIvol and DLP were decreased by 50.52% and 50.62% compare to images which is not applying AEC. mAs was increased by 61.5% to compensate image quality according to decreasing 20 kV when applying CAREkV. However, CTDIvol and DLP were decreased by 6.2% and 5.5%. When reference mAs was the lower and strength was the higher, reduction of radiation exposure rate was the bigger. Mean SD and DLP were decreased by 2.2% and 38% when applying SAFIRE even though mAs was decreased by 37.5%(from 40 mAs to 25 mAs). Combination of 3 methods test, SD decreased by 5.17% and there was no significant differences in spatial resolution. And mean SD and DLP were decreased by 6.7% and 36.9% compare to 120 kV, 40 mAs with AEC. For SUV test, there was no statistical differences(P>0.05). Conclusion Combination of 3 methods shows dose reduction effect without degrading image quality and SUV changes. To reduce radiation exposure in PET/CT study, continuous effort is needed by optimizing various dose reduction methods.