• Smart Structures and Systems
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• v.29 no.2
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• pp.301-309
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• 2022

Protective coatings are most widely used anticorrosive structures for steel structures. The corrosion under the coating damages the host material, but this damage is completely hidden. Therefore, a field-applicable under-coating-corrosion visualization method has been desired for a long time. Laser ultrasonic technology has been studied in various fields as an in situ nondestructive inspection method. In this study, a comparative analysis was carried out between a guided-wave ultrasonic propagation imager (UPI) and pulse-echo UPI, which have the potential to be used in the field of under-coating-corrosion management. Both guided-wave UPI and pulse-echo UPI were able to successfully visualize the corrosion. Regarding the field application, the guided-wave UPI performing Q-switch laser scanning and piezoelectric sensing by magnetic attachment exhibited advantages owing to the larger distance and incident angle in the laser measurement than those of the pulse-echo UPI. Regarding the corrosion visualization methods, the combination of adjacent wave subtraction and variable time window amplitude mapping (VTWAM) provided acceptable results for the guided-wave UPI, while VTWAM was sufficient for the pule-echo UPI. In addition, the capability of multiple sensing in a single channel of the guided-wave UPI could improve the field applicability as well as the relatively smaller size of the system. Thus, we propose a guided-wave UPI as a tool for under-coating-corrosion management.

• Journal of Oriental Neuropsychiatry
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• v.33 no.3
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• pp.259-266
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• 2022

Objectives: The combination of Harm-Avoidance (HA) and Self-Directedness (SD) of Temperament and Character Inventory (TCI) has been reported pivotal for mental health; however its clinical usefulness in integrative medicine has not sufficiently reported. The purpose of this study was to illustrate multi-phasic mental health of subjective satisfaction with life, emotional well-being, and psychopathology, following the HA-SD profile groups. Methods: A total of 527 Korean university students reported HA and SD scores as to render their HA-SD profile, and multi-phasic mental health characteristics using Satisfaction with Life Scale (SWLS), Positive Affect and Negative Affect Schedule (PANAS), and Beck Depression Inventory (BDI) with composite well-being scales of SC (Sum of Self-Directedness and Cooperativeness score) and HI (Happiness Index, subtraction of Negative Affect (NA) score from Positive Affect (PA) score) as standardized. Pearson's correlation was used to report correlation coefficient, and the ANCOVA with age and sex as covariates, to show significant differences in mental health and well-being between the HA-SD profile groups. Results: The HA-SD profile groups showed distinctive multi-phasic mental health characteristics; health related scores of SWLS, PA, SC and HI decreased following the order of hS (low HA and high SD), HS (high HA and high SD), hs (low HA and low SD) and Hs (high HA and low SD) profile groups; however the non-health related scores of NA and BDI showed contrasting order. Conclusions: The HA-SD profile was found to be clinically useful for examining multi-phasic mental health and well-being status, and the TCI may be an imperative personality inventory for integrative medicine.

• Journal of Korean Neurosurgical Society
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• v.65 no.5
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• pp.710-718
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• 2022

Objective : Although endovascular treatment for intracranial aneurysms is considered effective and safe, its durability is still debated. Also, few studies have described angiographic follow-up plan after endovascular treatment of intracranial aneurysm, especially in ruptured cases. Hence, we report the long-term results of follow-up angiography protocol. Methods : Radiological records of 639 cases of coil embolization with ruptured aneurysms from March 2003 to December 2016 were retrospectively reviewed. Patients who received treatment of a saccular aneurysm less than 7 mm resulted with near complete occlusion were included. Two hundred thirty-eight aneuryms which received the follow-up angiography at least once were enrolled. We classified four periods of follow-up as follows : post-treatment 1 year (defined as the first period), from 1 to 2 years (the second period), 2 to 5 years (the third period), and over 5 years (long-term). Results : We identified 14 cases (6.4%) of recurrence from 218 aneurysms in follow-up angiography in the first period. Among 143 aneurysms in the second period, five cases (3.5%) of recurrence were identified. There were no findings suspicious of recanalization in 97 patients in the third period. Of the total 238 cases, there were 19 recurrences, for a recurrence rate of 8.0%. Six (31.6%) out of 19 recurrences showed a tendency toward repeat recurrences even after additional treatment. Twenty-eight received long-term follow-up over 5 years and there was no recurrence. Conclusion : Most of the recurrence were found during the first and the second year. We suggest that at least one digital subtraction angiography examination may be necessary around post-treatment 2 years, especially in ruptured cases. If the angiographic results are favorable at 2 years post-treatment, long-term result should be favorable.

• Journal of the Korean School Mathematics Society
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• v.25 no.4
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• pp.307-332
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• 2022

This action research was carried out to help students learn fractions computation by making and using semi-concrete fraction manipulatives that can be used continuously in math classes. For this purpose, the researcher and students made semi-concrete fraction manipulatives and learned how to use these through reviewing the previously learned fraction contents over 4 class sessions. Afterward, through the 14 classes (7 classes for learning to reduce fractions and to a common denominator, 7 classes for adding and subtracting fractions with different denominators) in which the principle inquiry learning model was applied, students actively engaged in learning activities with fraction manipulatives and explored the principles underneath the manipulations of fraction manipulatives. Students could represent various fractions using fraction manipulatives and solve fraction computation problems using them. The achievement evaluation after class found that the students could connect the semi-concrete fraction manipulatives with fraction representation and symbolic formulas. Moreover, the students showed interest and confidence in mathematics through the classes using fraction manipulatives.

• The Mathematical Education
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• v.62 no.3
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• pp.341-362
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• 2023

This study analyzed student noticing in a lesson that emphasized relational understanding of equal signs for first graders from four aspects: centers of focus, focusing interactions, mathematical tasks, and nature of the mathematical activity. Specifically, the instructional factors that emphasize the relational understanding of equal signs derived from previous research were applied to a first-grade addition and subtraction unit, and then lessons emphasizing the relational understanding of equal signs were conducted. Students' noticing in this lesson was comprehensively analyzed using the focusing framework proposed in the previous study. The results showed that in real classroom contexts centers of focus is affected by the structure of the equation and the form of the task, teacher-student interactions, and normed practices. In particular, we found specific teacher-student interactions, such as emphasizing the meaning of the equals sign or using examples, that helped students recognize the equals sign relationally. We also found that students' noticing of the equation affects reasoning about equation, such as being able to reason about the equation relationally if they focuse on two quantities of the same size or the relationship between both sides. These findings have implications for teaching methods of equal sign.

• Journal of the Korea Society of Computer and Information
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• v.14 no.11
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• pp.179-186
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• 2009

In this paper, we propose a head detection method based on vertical and horizontal pixel histogram analysis in order to overcome drawbacks of the previous head detection approach using Haar-like feature-based face detection. In the proposed method, we create the vertical and horizontal foreground pixel histogram images from the background subtraction image, which represent the number of foreground pixels in the same vertical or horizontal position. Then we extract feature points of a head region by applying Harris corner detection method to the foreground pixel histogram images and by analyzing corner points. The proposal method shows robust head detection results even in the face image covering forelock by hairs or the back view image in which the previous approaches cannot detect the head regions.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1563-1570
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• 2023

In this study, a DeCART/MIG uncertainty quantification (UQ) analysis code system with a multicorrelated cross section stochastic sampling (S.S.) module was established and verified through the UAM (Uncertainty Analysis in Modeling) and the BEAVRS (Benchmark for Evaluation And Validation of Reactor Simulations) benchmark calculations. For the S.S. calculations, a sample of 500 DeCART multigroup cross section sets for two major actinides, i.e., ²³⁵U and ²³⁸U, were generated by the MIG code and covariance data from the ENDF/B-VII.1 evaluated nuclear data library. In the three pin problems (i.e. TMI-1, PB2, and Koz-6) from the UAM benchmark, the uncertainties in k_inf by the DeCART/MIG S.S. calculations agreed very well with the sensitivity and uncertainty (S/U) perturbation results by DeCART/MUSAD and the S/U direct subtraction (S/U-DS) results by the DeCART/MIG. From these results, it was concluded that the multi-group cross section sampling module of the MIG code works correctly and accurately. In the BEAVRS whole benchmark problems, the uncertainties in the control rod bank worth, isothermal temperature coefficient, power distribution, and critical boron concentration due to cross section uncertainties were calculated by the DeCART/MIG code system. Overall, the uncertainties in these design parameters were less than the general design review criteria of a typical pressurized water reactor start-up case. This newly-developed DeCART/MIG UQ analysis code system by the S.S. method can be widely utilized as uncertainty analysis and margin estimation tools for developing and designing new advanced nuclear reactors.

• 한국노년학
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• v.31 no.4
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• pp.1103-1118
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• 2011

This study aims to examine the effects of employment on the physical health, psychological function, and life satisfaction of the elderly. Participants were 4,165 persons (men 1,739, women 2,426) aged 65 over. Physical health was composed of ADLs(Activities of daily living), pains, and disorders. Psychological function was measured by cognitive functions (subtraction, instruction execution, memory test, and item use) and emotional difficulty. Life satisfaction, work satisfaction, and work level were also measured. Major findings in this study are as follows: First, gender, marriage, and education level had significant effects on the participants' life satisfaction, but religion and financial incomes did not. Second, employment had significant effects on their physical health, psychological function, and life satisfaction. Third, pain, cognitive functions, emotional difficulty, and work satisfaction had significant effects on the life satisfaction of the working elderly. But, work level and incomes had not significant effects on the elderly's life satisfaction. In addition, an interaction between cognitive functions and emotional difficulty on life satisfaction was found.

• Journal of radiological science and technology
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• v.46 no.5
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• pp.427-433
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• 2023

This study aimed to quantitatively compare the diameters measured directly from the coronal plane or sagittal plane of 2D digital subtraction angiography (DSA) and the cross-sectional area-converted diameters calculated from contrast-enhanced MR (CE-MR) imaging. A retrospective analysis was conducted on 20 patients who underwent both 2D DSA and CE-MR imaging. Firstly, the venous diameters of the superior sagittal sinus (SSS) and transverse sinus (TS) were directly measured from 2D DSA. Subsequently, the axial planes for SSS diameter and the sagittal plane for TS in CE-MR imaging were utilized to calculate cross-sectional area-based converted diameters. The numerical values obtained from 2D DSA and CE-MR imaging were compared pairwise at each location. For SSS, the diameter measured by 2D DSA was 27% larger than the conversion-based diameter from CE-MR imaging (9.8±1.4 mm vs. 7.1±1.3 mm, P<0.05). Similarly, for the right TS, the difference was 16% (8.8±3.2 mm vs. 7.4±2.0 mm, P<0.05), and for the left TS, the difference was 22% (8.4±2.8 mm vs. 6.6±1.3 mm, P<0.05). In conclusion, the diameter measured directly in conventional 2D DSA may be larger than the diameter converted based on the cross-sectional area. Therefore, when selecting the size of the stent, it is crucial to make precise determinations while keeping this fact in mind.

• Genomics & Informatics
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• v.21 no.3
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• pp.42.1-42.23
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• 2023

Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis, one of the most deadly infections in humans. The emergence of multidrug-resistant and extensively drug-resistant Mtb strains presents a global challenge. Mtb has shown resistance to many frontline antibiotics, including rifampicin, kanamycin, isoniazid, and capreomycin. The only licensed vaccine, Bacille Calmette-Guerin, does not efficiently protect against adult pulmonary tuberculosis. Therefore, it is urgently necessary to develop new vaccines to prevent infections caused by these strains. We used a subtractive proteomics approach on 23 virulent Mtb strains and identified a conserved membrane protein (MmpL4, NP_214964.1) as both a potential drug target and vaccine candidate. MmpL4 is a non-homologous essential protein in the host and is involved in the pathogen-specific pathway. Furthermore, MmpL4 shows no homology with anti-targets and has limited homology to human gut microflora, potentially reducing the likelihood of adverse effects and cross-reactivity if therapeutics specific to this protein are developed. Subsequently, we constructed a highly soluble, safe, antigenic, and stable multi-subunit vaccine from the MmpL4 protein using immunoinformatics. Molecular dynamics simulations revealed the stability of the vaccine-bound Tolllike receptor-4 complex on a nanosecond scale, and immune simulations indicated strong primary and secondary immune responses in the host. Therefore, our study identifies a new target that could expedite the design of effective therapeutics, and the designed vaccine should be validated. Future directions include an extensive molecular interaction analysis, in silico cloning, wet-lab experiments, and evaluation and comparison of the designed candidate as both a DNA vaccine and protein vaccine.