• Korean Journal of Radiology
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• v.24 no.2
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• pp.155-165
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• 2023

Objective: Little is known about the effects of using different expert-determined reference standards when evaluating the performance of deep learning-based automatic detection (DLAD) models and their added value to radiologists. We assessed the concordance of expert-determined standards with a clinical gold standard (herein, pathological confirmation) and the effects of different expert-determined reference standards on the estimates of radiologists' diagnostic performance to detect malignant pulmonary nodules on chest radiographs with and without the assistance of a DLAD model. Materials and Methods: This study included chest radiographs from 50 patients with pathologically proven lung cancer and 50 controls. Five expert-determined standards were constructed using the interpretations of 10 experts: individual judgment by the most experienced expert, majority vote, consensus judgments of two and three experts, and a latent class analysis (LCA) model. In separate reader tests, additional 10 radiologists independently interpreted the radiographs and then assisted with the DLAD model. Their diagnostic performance was estimated using the clinical gold standard and various expert-determined standards as the reference standard, and the results were compared using the t test with Bonferroni correction. Results: The LCA model (sensitivity, 72.6%; specificity, 100%) was most similar to the clinical gold standard. When expert-determined standards were used, the sensitivities of radiologists and DLAD model alone were overestimated, and their specificities were underestimated (all p-values < 0.05). DLAD assistance diminished the overestimation of sensitivity but exaggerated the underestimation of specificity (all p-values < 0.001). The DLAD model improved sensitivity and specificity to a greater extent when using the clinical gold standard than when using the expert-determined standards (all p-values < 0.001), except for sensitivity with the LCA model (p = 0.094). Conclusion: The LCA model was most similar to the clinical gold standard for malignant pulmonary nodule detection on chest radiographs. Expert-determined standards caused bias in measuring the diagnostic performance of the artificial intelligence model.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.27 no.3
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• pp.168-175
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• 2024

Purpose: The presence of alcoholic stool in biliary atresia (BA) patients is the basis of a stool color card (SCC), a screening tool that has led to more patients receiving Kasai portoenterostomy earlier. This study aimed to evaluate the color image processing of stool images captured using smartphones. We propose that measuring digital color parameters is a more objective method for identifying BA stools and may improve the sensitivity of BA screening. Methods: A prospective study was conducted in five hospitals in Thailand between October 1, 2020, and December 31, 2021. Stools from infants presenting with jaundice, acholic stool, or dark-colored urine were photographed. Digital image color analysis was performed, and software was developed based on the color on the original SCC. Sensitivity and specificity for predicting BA stools were compared between the SCC and the software. Results: Of 33 infants eligible for data collection, 19 were diagnosed with BA. Saturation and blue were two potential digital color parameters used to differentiate BA stools. The receiver operating characteristic curve was used to determine the optimum cutoff point of both values, and when saturation ≤56 or blue ≥61 was set as a threshold for detecting BA stool, high accuracy was achieved at 81.8% and 78.8%, respectively. Conclusion: Digital image processing is a promising technology. With appropriate cutoff values of saturation in hue, saturation, value and blue in red, green, blue color models, BA stools can be identified, and equivocal-colored stools of non-BA patients can be differentiated with acceptable accuracy in infants presenting with jaundice.

• Tribology and Lubricants
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• v.40 no.3
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• pp.103-110
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• 2024

Gas foil thrust bearings (GFTBs) are oil-free self-acting hydrodynamic bearings that support axial loads with a low friction during airborne operation. They need solid lubricants to reduce dry-friction between the runner and top foil and minimize local wears on their surfaces during start-up and shutdown processes. In this study, we evaluate the lift-off speeds and load capacity performance of a GFTB with Polytetrafluoroethylene (PTFE) surface coating by measuring drag torques during a series of experimental tests at increasing ambient temperatures of 25, 75 and 110℃. An electric heat gun provides hot air to the test GFTB operating in the closed booth to increase the ambient temperature. Test results show that the increasing ambient temperature delays the lift-off speed and decreases the load capacity of the test GFTB. An early developed prediction tool well predicts the measured drag torques at 60 krpm. After all tests, post inspections of the surface coating of the top foil are conducted. Scanning electron microscope (SEM) images imply that abrasive wear and oxidation wear are dominant during the tests at 25℃ and 110℃, respectively. A quantitative energy dispersive spectroscopy (EDS) microanalysis reveals that the weight percentages of carbon, oxygen, and nitrogen decrease, while that of fluorine increases significantly during the highest-temperature tests. The study demonstrates that the increasing ambient temperature noticeably deteriorates the static performances and degrades the surface coating of the test GFTB.

• Anxiety and mood
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• v.20 no.1
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• pp.27-34
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• 2024

Objective : Cognitive fusion, or believability, in acceptance and commitment therapy (ACT), refers to the tendency to become entangled in one's thoughts or feelings. It is an important factor in the development and maintenance of anxiety disorders. However, there is a lack of validated self-report measures for cognitive fusion and defusion, particularly for individuals with anxiety. To address this gap, this study aimed to evaluate the Korean Version of Believability of Anxious Feelings and Thoughts Questionnaire (K-BAFT). Methods : A total of 608 university students and 85 patients with obsessive-compulsive disorder (OCD) took part in this study. They were asked to complete various psychological measures, including the K-BAFT, other measures of ACT processes, and symptom scales. The researchers then analyzed the psychometric characteristics of the K-BAFT. Results : The results of the exploratory and confirmatory factor analyses indicated that the three-factor structure of the K-BAFT, which was reported in the original study, was also found in the university sample. Additionally, both the student and the OCD group demonstrated strong internal consistency (α=0.86 and 0.91, respectively). In the university sample, the K-BAFT showed a strong correlation with the Cognitive Fusion Questionnaire (r_s=0.53, p<0.001). However, it had a weak correlation with symptoms scales for depression, anxiety, and stress (all r_s<0.32). Furthermore, the OCD group had higher scores on the K-BAFT compared to the university sample. Conclusion : K-BAFT is considered to be a reliable and valid self-report tool for measuring cognitive fusion with anxious thoughts and feelings.

• Physical Therapy Korea
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• v.31 no.2
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• pp.114-122
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• 2024

Background: The peroneus longus (PL) and peroneus brevis (PB) function as the primary muscles of eversion, a movement closely associated with tibial external rotation for ankle mortise stability. Ankle motion and tibial rotation vary based on different ankle and knee positions. Objects: This study aimed to investigate the PL, PB, and biceps femoris (BF) muscle activation and eversion strength during side-lying isometric eversion exercise based on different ankle positions (neutral [N] and plantarflexion [PF]) and knee positions (90° flexion [KF] and extension [KE]). Methods: Thirty healthy adults with an Ankle Joint Functional Assessment Tool score of ≥ 22 were recruited (mean age = 24.8 ± 3.1 years). Maximal isometric eversion strength and submaximal muscle activation of the PL, PB and BF were measured during isometric eversion exercise in side-lying. A 2 × 2 repeated measures analysis of variance was performed to investigate differences in muscle activation and strength. Results: The PL and PB muscle activation showed significant main effects with the knee and ankle positions (p < 0.05); activation was greater in the KE and PF positions than in the KF and N positions. The BF muscle activation showed a significant interaction effect with knee and ankle positions, which was greater in knee extension and ankle plantarflexed (KEPF) position than in knee flexion and ankle plantarflexed (KFPF) position (p < 0.05). Eversion strength showed a significant main effect only in ankle position (p < 0.05) and was greater in the N position than in the PF position. Conclusion: The results of this study indicate that the KEPF position can be recommended to facilitate contraction of the PL and PB during side-lying eversion exercise. Furthermore, the effects of the knee-ankle positions should be considered for measuring ankle eversion strength and implementing the isometric submaximal side-lying eversion exercise.

• Computers and Concrete
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• v.34 no.2
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• pp.247-265
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• 2024

Measuring the fracture toughness of concrete in laboratory settings is challenging due to various factors, such as complex sample preparation procedures, the requirement for precise instruments, potential sample failure, and the brittleness of the samples. Therefore, there is an urgent need to develop innovative and more effective tools to overcome these limitations. Supervised learning methods offer promising solutions. This study introduces seven machine learning algorithms for predicting concrete's effective fracture toughness (K-eff). The models were trained using 560 datasets obtained from the central straight notched Brazilian disc (CSNBD) test. The concrete samples used in the experiments contained micro silica and powdered stone, which are commonly used additives in the construction industry. The study considered six input parameters that affect concrete's K-eff, including concrete type, sample diameter, sample thickness, crack length, force, and angle of initial crack. All the algorithms demonstrated high accuracy on both the training and testing datasets, with R² values ranging from 0.9456 to 0.9999 and root mean squared error (RMSE) values ranging from 0.000004 to 0.009287. After evaluating their performance, the gated recurrent unit (GRU) algorithm showed the highest predictive accuracy. The ranking of the applied models, from highest to lowest performance in predicting the K-eff of concrete, was as follows: GRU, LSTM, RNN, SFL, ELM, LSSVM, and GEP. In conclusion, it is recommended to use supervised learning models, specifically GRU, for precise estimation of concrete's K-eff. This approach allows engineers to save significant time and costs associated with the CSNBD test. This research contributes to the field by introducing a reliable tool for accurately predicting the K-eff of concrete, enabling efficient decision-making in various engineering applications.

• Journal of the korean academy of Pediatric Dentistry
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• v.51 no.3
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• pp.299-309
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• 2024

This study aimed to assess the competency of artificial intelligence (AI) in pediatric dentistry and compare it with that of dentists. We used open-source data obtained from the Korea Health Personnel Licensing Examination Institute. A total of 32 item multiple-choice pediatric dentistry exam questions were included. Two AI-based chatbots (ChatGPT 3.5 and Gemini) were evaluated. Each chatbot received the same questions seven times in separate chat sessions initiated on April 25, 2024. The accuracy was assessed by measuring the percentage of correct answers, and consistency was evaluated using Cronbach's alpha coefficient. Both ChatGPT 3.5 and Gemini demonstrated similar accuracy, with no significant differences observed between them. However, neither chatbot achieved the minimum passing score set by the Pediatric Dentistry National Examination. However, both chatbots exhibited acceptable consistency in their responses. Within the limits of this study, both AI-based chatbots did not sufficiently answer the pediatric dentistry exam questions. This finding suggests that pediatric dentists should be aware of the advantages and limitations of this new tool and effectively utilize it to promote patient health.

• Asian Oncology Nursing
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• v.1 no.2
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• pp.191-203
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• 2001

The health of a nurse is very important because her mental and physical health can influence toward nursing patients directly, Especially, Cancer patients are growing annually. Also, terminal cancer patients' nursing and dead place are increasingly using hospital and the period of nursing for cancer patients are increasing. Nursing for cancer patients are different with acute disease. Therefore, I analysed comparing nurses' health working in cancer and general ward so that nurses working at cancer ward could be developed as a professional nurse, and I wanted to establish the foundation of nursing administration and reasonable manpower management to supply good quality of nursing to patients. In my research, I selected 117 nurses working in cancer ward and 134 nurses working in general word to analyse the stress rate and nurse's health comparing nurses working in general ward and cancer ward. The survey was conducted of nurses working in cancer ward nurses in 2 university hospitals, nurses working in a cancer hospital, and general ward nurses working in 3 public hospital. Also, the data was collected from Sep. 13, 2001 to Sep. 28, 2001. As health measuring tool, I used Cornell Medical Index(CMI) which are developed to fit Koreans by Ko Ungrin and Park Hang-bas (1980) using Cornell Medical Services which were designed by Weiser, Brosman, Mittelman, Wechler, Wolff in Cornell University(1945). As working stress measuring tool, I used Questionaries which were designed by Kim Mae-ja and Ku Mi-ok(1984) and then developed by Bae In-sook(1996). For managing the data, I used frequency, percentage, ${\chi}^2$ verification, t-test, and F-test (ANOVA). And in the case of significant data(p<.05). I did Duncan's test for post verification. The mutual relation between health condition and working stress rate have been conducted using Pearson's Correlation Coefficient. Followings are the results of my research. 1. Two groups showed significant differency at age after testing homogeneous character between two groups (${\chi}^2$ =9.919, p=.007). 2. Comparing two group's health condition, cancer ward(average 19.35${\pm}$18.34) were higher than general ward(14.42${\pm}$10.59) and showed statistical significant differency(p=.009). And, comparing two group's mental condition, cancer ward(9.00${\pm}$9.79) were higher than general ward(7.13${\pm}$6.35) and statistically no differency. 3. After comparing two group's working stress rate, the rate of cancer ward nurse's working stress(3.36${\pm}$.50) is higher than general ward nurse (3.32${\pm}$.48). There are no significant differency. However, in the detailed verification test, there were significant differency at inappropriate compensation (t=3.254, p=.001) and medication issue (t=2.170, p=.031). 4. After comparing health condition at general points, physical health condition showed significant differency at age(p=.020), the number of children (p=.015), religion (p=.015), position(p=.005), career(p=.008), working satisfaction(p=.003), activity after office hour(p=.045); and mental health condition showed significant differency at position(p=.010), career (p=.017), working satisfaction (p=.003). 5. After comparing the working stress rate according to general points, there were significant differency at working satisfaction (F=5.285, p=.006), predicted nursing(F=3.822, p=.023). 6. At the relation of health condition and working stress rate between two groups. physical and mental condition showed significant relation with working stress rate. i.e, if a nurse's health condition is not good, she are feeling much more stress than others. After considering all the factors in my research, I found that the health condition and stress rate of cancer ward nurses is much higher than general ward nurses. Considering that cancer ward nurses is necessary to care for increasing cancer patients with mental and physical nursing, the less stress for cancer ward nurses is very important to develop nursing quality and working efficiency by keeping good health condition, specializing cancer ward nurses. Therefore, we need following studies to find the factors which are effecting to cancer ward nurses' health and specialization. Also, we need to improve managing working condition to decrease working stress by improving working condition.

• Journal of agricultural medicine and community health
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• v.26 no.1
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• pp.81-103
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• 2001

This study was conducted to identify the health behavior of middle-aged rural women and the factors that have an effect on them. For the purpose of the study, examinations were made from March 01, 2000 to March 31, 2000 with 468 women aged 40 to 64 out of 2,263 people whom four Primary Health Posts located in Yechon County, Kyongsangbuk-do Province, are in charge of. The results are summarized as follows. 17.5% of the subjects responded that the extent of their own interest in health were high. For the subjects having a chronic disease, a nuclear family, or an open family atmosphere, the extent appeared to be relatively higher, 15.4% responded that the extent of family's interest in their health was high. It was significantly high if the extent of education was high or if the family atmosphere was open. The subjects' average score of self-efficacy was 49.9 out of 68. The score significantly varied depending on religion, education, living together with a spouse or not, and the extent of the subjects' interest in health. The family pattern, family atmosphere, family's interest in the subjects' health were the variables that significantly influenced the self-efficacy. The average score of family function was 5.51 out of 10. The score significantly varies depending on age, education, occupation, financial status, the extent of the subjects' own interest in health, family atmosphere and family's interest in the subjects' health. In the practice of health behavior, the nonsmoking rate was 89.5%, the nondrinking rate 63.0%, the rate of exercising practice 6.6%, the rate of normal sleeping 75.6%, the rate of eating breakfast 91.7%, the rate of not eating between meals 18.2%, and the standard BMI 69.2%. In the frequency of health behavior, the subjects with the Breslow Index of 0-3, 4-5 and 6-7 accounted for 4.5%, 53.2%, and 42.3%, respectively. The average score of health behavior was 5.20 out of 7, in which significant variables were living together with a spouse or not, financial status, absence or presence of a chronic disease, and family atmosphere. In the multiple regression analysis with health behavior as a dependent variable, it was shown that living together with a spouse or not, financial status, and family atmosphere were the significantly substantial variables. The subjects were found to do health behavior well if they had not a spouse, a good financial status, or an open family atmosphere. They were also found to do health behavior well if the extent of self-efficacy was high or if the extent of family function was low, but these were not the significant variables. It is needed to develop a standard measuring tool fit for our environment and perform more studies in the future because the measuring tool used in this study was a tool developed in a foreign county. In promoting community health projects, it is required not to provide all community people with a uniform health program but to identify the health behavior of individuals and other variables such as living together with a spouse or not, financial status and family atmosphere before arranging for a proper health program.

• 한국노년학
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• v.41 no.2
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• pp.197-215
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• 2021

This study aims to evaluate Person Centered Care practice and characteristics of care services in Korean long-term care facilities using Dementia Care Mapping as a tool. DCM, systematic observational evaluation tool for measuring dementia patients' QOL, was transformed into self-report rating scale. The process of transforming DCM into a scale of 34 items involves operationalization of DCM concepts and it's adaptation into Korean long-term care practices. Review by research team of Bradford university was added to maintain DCM concept and meaning in this scale. The scale with Cronbach alpha of .88 was surveyed on 343 care workers. Survey result shows PCC value practiced by them is 3.77(of 5 likert scale) and values on each categories of PCC reveal the characteristics of care in Korean facilities; attachment(4.02), comfort(3.95), inclusion(3.89), identity(3.67) and occupation(3.41). Dementia care in Korean facilities focuses on recipients'safety, comfort but lacks individualistic care and the meaningful and fulfilling occupation for patients. Looking at the organizational and individual factors influencing DCM values, the small facilities showed higher PCC values and there are no significant difference in PCC values between public and private facilities. Managers and care workers with career of 1~2 years showed higher PCC values compared to other career ranks and lengthes. This study suggests care practice should be centered on personhood of patients in long-term care facilities, for which introduction of unit care and education of PCC for service providers including support personnel are needed. DCM and Korean DCM scale developed in this study are suggested for the PCC-based assessment on care quality.