• Korean Journal of Radiology
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• v.22 no.11
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• pp.1850-1857
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• 2021

Objective: The purpose of this study was to assess whether a deep learning (DL) algorithm could enable simultaneous noise reduction and edge sharpening in low-dose lumbar spine CT. Materials and Methods: This retrospective study included 52 patients (26 male and 26 female; median age, 60.5 years) who had undergone CT-guided lumbar bone biopsy between October 2015 and April 2020. Initial 100-mAs survey images and 50-mAs intraprocedural images were reconstructed by filtered back projection. Denoising was performed using a vendor-agnostic DL model (ClariCT.AI^TM, ClariPI) for the 50-mAS images, and the 50-mAs, denoised 50-mAs, and 100-mAs CT images were compared. Noise, signal-to-noise ratio (SNR), and edge rise distance (ERD) for image sharpness were measured. The data were summarized as the mean ± standard deviation for these parameters. Two musculoskeletal radiologists assessed the visibility of the normal anatomical structures. Results: Noise was lower in the denoised 50-mAs images (36.38 ± 7.03 Hounsfield unit [HU]) than the 50-mAs (93.33 ± 25.36 HU) and 100-mAs (63.33 ± 16.09 HU) images (p < 0.001). The SNRs for the images in descending order were as follows: denoised 50-mAs (1.46 ± 0.54), 100-mAs (0.99 ± 0.34), and 50-mAs (0.58 ± 0.18) images (p < 0.001). The denoised 50-mAs images had better edge sharpness than the 100-mAs images at the vertebral body (ERD; 0.94 ± 0.2 mm vs. 1.05 ± 0.24 mm, p = 0.036) and the psoas (ERD; 0.42 ± 0.09 mm vs. 0.50 ± 0.12 mm, p = 0.002). The denoised 50-mAs images significantly improved the visualization of the normal anatomical structures (p < 0.001). Conclusion: DL-based reconstruction may enable simultaneous noise reduction and improvement in image quality with the preservation of edge sharpness on low-dose lumbar spine CT. Investigations on further radiation dose reduction and the clinical applicability of this technique are warranted.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.3
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• pp.341-347
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• 2015

Purpose : This study was to examine a correlation of response AC/A ratio by additional spherical powers with PD(Pupilary distance) and relative accommodation, and was to investigate correlation of CA/C ratio by prism powers. The mean differences between a reciprocal response AC/A ratio and a CA/C ratio were compared, and were suggested to be used as data in the refractive power and prism prescriptions in the clinical. Methods: The open field autorefractometer (Nvision-K 5001, Shin nippon) and Howell target at 40 cm fixation distance to 62 persons with average $22.62{\pm}2.84$ ages were used to measure the response AC/A ratio according to additional Spherical powers. The CA/C ratios were measured using the DOG card at 40cm according to prism powers. Results: When the response accommodation according to Additional Spherical power changes and the response accommodation according to prism power changes were compared, it was larger than the response accommodation according prism power change. These were significant differences statistically. The correlation of response AC/A ratio and PD is showed as r = -0.158, the CA / C ratio is shown as r = 0.093. The correlation of response AC/A ratio and relative accommodation showed as r = -0.253, the CA/C ratio showed as r = 0.566 that is predictable correlation. The correlation of response AC/A ratio and CA/C ratio showed as r = -0.355 that is low minus correlation (p = 0.000). The difference between a reciprocal response AC/A ratio and a CA/C ratio showed $0.12{\pm}0.06D/{\Delta}$ with a significant difference statistically (p=0.000). Conclusions: The correlation of relative accommodation and CA/C ratio showed that depend on the individual, The more a relative accommodation is, the higher a response accommodation of convergence by convergence stimulus is. The reciprocal response AC/A and CA/C ratio showed significant differences statistically. This can have higher CA/C ratio in patients with low AC/A ratio in clinical as an independent variable. Thus when the abnormal binocular vision was prescribed in the clinical, it is necessary to consider the accommodative response even if the AC/A ratio is a normal range.

• Ultrasonography
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• v.32 no.1
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• pp.59-65
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• 2013

Purpose: The purpose of this study is to establish the methodology regarding synthesis of ultrasound contrast agent imaging, and to evaluate the characteristics of the synthesized ultrasound contrast agents, including size or degradation interval and image quality. Materials and Methods: The ultrasound contrast agent, composed of liposome and SF6, was synthesized from the mixture solution of $21{\mu}mol$ DPPC (1, 2-Dihexadecanoyl-sn-glycero-3-phosphocholine, $C_{40}H_{80}NO_8P$), $9{\mu}mol$ cholesterol, $1.9{\mu}mol$ of DCP (Dihexadecylphosphate, $[CH_3(CH_2)_{15}O]_2P(O)OH$), and chloroform. After evaporation in a warm water bath and drying during a period of 12-24 hours, the contrast agent was synthesized by the sonication process by addition of buffer and SF6 gas. The size of the contrast agent was controlled by use of either extruder or sonication methods. After synthesis of contrast agents, analysis of the size distribution of the bubbles was performed using dynamic light scattering measurement methods. The degradation curve was also evaluated by changes in the number of contrast agents via light microscopy immediate, 12 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72 hours, and 84 hours after synthesis. For evaluation of the role as an US contrast agent, the echogenicity of the synthesized microbubble was compared with commercially available microbubbles (SonoVue, Bracco, Milan, Italy) using a clinical ultrasound machine and phantom. Results: The contrast agents were synthesized successfully using an evaporation-drying-sonication method. The majority of bubbles showed a mean size of 154.2 nanometers, and they showed marked degradation 24 hours after synthesis. ANOVA test revealed a significant difference among SonoVue, synthesized contrast agent, and saline (p < 0.001). Although no significant difference was observed between SonoVue and the synthesized contrast agent, difference in echogenicity was observed between synthesized contrast agent and saline (p < 0.01). Conclusion: We could synthesize ultrasound contrast agents using an evaporation-drying-sonication method. On the basis of these results, many prospective types of research, such as anticancer drug delivery, gene delivery, including siRNA or microRNA, targeted molecular imaging, and targeted therapy can be performed.

• Journal of Digital Convergence
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• v.19 no.4
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• pp.141-149
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• 2021

The purpose of this study was to identify the intention to use of information and communication technology(ICT) for the elderly residing in community based on the theory of planned behavior. The subjects were 99 elderly aged 60 or older living in G and S cities from January 1 to 31 in 2020 using questionnaire. The data was analyzed using the SPSS 23.0 program for descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, multiple regression. As a result, the mean of the attitude to use of ICT for the elderly was 3.79±0.74, subjective norm was 3.43±0.66, perceived behavioral control was 3.12±0.71, behavior intention was 3.23±0.77. The intent to use of ICT for the elderly are subjective norm(β=.35, p<.001), perceived behavior control(β=.35, p<.001), had an explanatory power of 48.7%. Therefore, it is necessary that systematic program considering the above factors for elderly residing in community to promote the intent to use of ICT.

• Therapeutic Science for Rehabilitation
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• v.12 no.3
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• pp.61-77
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• 2023

Objective : This study analyzed the correlation between cognitive function and oral health-related quality of life (OHQoL). Methods : Demographic and clinical characteristics were extracted and utilized for subjects aged 45 years or older who participated in the 8th Korean Longitudinal Study on Aging in 2020. The dependent variable was the Geriatric Oral Health Assessment Index, and the independent variable was the level of cognitive function classified by the Mini-Mental State Examination scores. The analysis method used inverse probability of treatment weighting (IPTW). Then, the association between cognitive function and OHQoL was analyzed by multiple regression analysis. Results : Among the participants, 4,367 (71.40%) had normal cognition, 1,155 (18.89%) had moderate cognitive impairment, and 594 (9.71%) had severe cognitive impairment. As a result of analysis by applying IPTW, there was a negative correlation between the cognitive function group and OHQoL (normal vs. moderate: β = -2.534, p < .0001; normal vs. severe: β = -2.452, p < .0001). Conclusion : After propensity score matching, mild cognitive impairment showed a more negative association than severe cognitive impairment. Therefore, patients with cognitive impairment require oral health management education to improve OHQoL regardless of the level of cognitive impairment.

• Therapeutic Science for Rehabilitation
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• v.12 no.2
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• pp.85-98
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• 2023

Objective : We investigated the efficacy of an artificial intelligence computerized cognitive training program using motion capture to identify changes in cognition, depression, and quality of life in older adults with mild cognitive impairment. Methods : A total of seven older adults (experimental group = 4, control group = 3) participated in this study. During the COVID-19 period from October to December 2021, we used a program, "MOOVE Brain", that we had developed. The experimental group performed the program 30 minutes 3×/week for 1 month. We analyzed patients scores from the Korean version of the Mini-Mental State Examination-2, the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet for Daily Life Evaluation, the short form Geriatric Depression Scale, and Geriatric Quality of Life Scale. Results : We observed positive changes in the mean scores of the Stroop Color Test (attention), Stroop Color/Word Test (executive function), SGDS-K (depression), and GQOL (QoL). However, these changes did not reach statistical significance for each variable. Conclusion : The study results from "MOOVE Brain" can help address cognitive and psychosocial issues in isolated patients with MCI during the COVID-19 pandemic or those unable to access in-person medical services.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1185-1193
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• 2023

The increasing interest in soil moisture data from satellite imagery for applications in hydrology, meteorology, and agriculture has led to the development of methods to produce variable-resolution soil moisture maps. Research on accurate soil moisture estimation using satellite imagery is essential for remote sensing applications. The purpose of this study is to generate a soil moisture estimation map for a test area using KOMPSAT-3/3A and KOMPSAT-5 SAR imagery and to quantitatively compare the results with soil moisture data from the Soil Moisture Active Passive (SMAP) mission provided by NASA, with a focus on accuracy validation. In addition, the Korean Environmental Geographic Information Service (EGIS) land cover map was used to determine soil moisture, especially in agricultural and forested regions. The selected test area for this study is the western part of Jeju, South Korea, where input data were available for the soil moisture estimation algorithm based on the Water Cloud Model (WCM). Synthetic Aperture Radar (SAR) imagery from KOMPSAT-5 HV and Sentinel-1 VV were used for soil moisture estimation, while vegetation indices were calculated from the surface reflectance of KOMPSAT-3 imagery. Comparison of the derived soil moisture results with SMAP (L-3) and SMAP (L-4) data by differencing showed a mean difference of 4.13±3.60 p% and 14.24±2.10 p%, respectively, indicating a level of agreement. This research suggests the potential for producing highly accurate and precise soil moisture maps using future South Korean satellite imagery and publicly available data sources, as demonstrated in this study.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.1143-1149
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• 2023

The purpose of this study was to the effects of case-based learning (CBL) on problem solving ability and academic self-efficacy in nursing students and was a quasi-experimental study with a one-group pretest-posttest design. The subjects of this study were 121 grade 4 students, and the data collection period was from Aprill 24 to June 12, 2023. The research procedure was scenario development, preliminary investigation, application of case-based learning classes, and follow-up investigation, and the CBL was conducted for 2 weeks, 50 minutes per week. The general characteristics of the subjects were obtained by frequency, percentage, mean, and standard deviation and the effects of CBL on problem solving ability and academic self-efficacy was tested using a paired t-test. The results of this study showed that nursing students' problem solving ability (t=-5.70, p<.001) and academic self-efficacy (t=-3.25, p<.002) improved after applying CBL compared to before applying it. We suggest the use of case-based learning as a strategy to improve problem-solving skills and academic self-efficacy in nursing education. In the future, follow-up research is needed to verify the effectiveness by developing and applying step-by-step clinical cases at an appropriate level according to the learning content of nursing major subjects by grade.

• Journal of Digital Convergence
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• v.13 no.11
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• pp.255-265
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• 2015

This study was done to identify the levels of knowledge and attitude toward HIV/AIDS in professional graduate medical school students. A cross-sectional survey was used, and data were collected in 2014. Participants were 97 students in South Korea. Data were analyzed using SPSS WIN 19.0 program. The mean score for HIV/AIDS knowledge was 8.91 and attitude was 7.00 out of 15. The levels of HIV/AIDS knowledge and attitude were not statistically significantly different according to participants' general characteristics. There was a statistically significant correlation between the levels of HIV/AIDS knowledge and attitude. Medical students having a high HIV/AIDS knowledge level tended more towards a positive attitude. These findings can be used in developing effective education strategies for medical students and health care providers to increase knowledge and decrease negative attitude toward HIV/AIDS.

• Journal of Industrial Convergence
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• v.18 no.3
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• pp.35-43
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• 2020

This study was to identify the factors influencing the person centered care competency in nursing students. Data were conducted on 294 nursing students from September 1st to 25th 2019. The mean score of critical thinking disposition was 3.72, the interpersonal relationship was 3.90 and person centered care competency was 4.01. Nursing students with high degree of major satisfaction had higher level of critical thinking disposition, the interpersonal relationship and person centered care competency than students with low degree. Significant factors influencing person centered care competency were critical thinking disposition, the interpersonal relationship and grade which explained 33%. The programs that develop critical thinking disposition and interpersonal relationship are necessary for college nursing students in order to promote person centered care competency.