• Journal of the Korean Chemical Society
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• v.67 no.5
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• pp.362-377
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• 2023

The purpose of this study was to investigate the effect of semantic mapping as a science text reading strategy on high school students' inferential understanding. For this purpose, eight science text reading classes were conducted a reading strategy using semantic mapping for 46 students in two science-focused classes in the third grade of a high school. To investigate the effects of semantic mapping reading strategy on students' inferential comprehension, students' pre- and post-reading ability tests results were analyzed. In order to find out the change in inferential comprehension, the level of the inferential comprehension was analyzed using the analysis framework for developed in this study. For the classification of inferential comprehension, the levels of the inferential comprehension were converted into scores. The results of the analysis of changes in students' inferential comprehension showed that semantic mapping reading strategy classes influenced the changes in high school students' inference, especially bridge inference and elaborative inference among sub-elements of inferential comprehension.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.1
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• pp.126-142
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• 2023

The purpose of this study is to develop unmanned traffic enforcement equipment and standard specifications for the prevention of traffic accidents and violations of the two-wheeled vehicle laws. To this end, we conducted a review of the problems and new technologies of the currently operating unmanned traffic enforcement equipment on two-wheeled vehicles. And through a survey, the feasibility of introducing unmanned traffic enforcement equipment for two-wheeled vehicles and the current status of technology were investigated. In addition, the two-wheeled vehicle enforcement function was implemented through field tests of the development equipment, and the addition of enforcement targets and the number recognition rate were improved through performance improvement. Based on the results of field experiments and performance evaluation, performance standards for unmanned two-wheeled vehicle traffic enforcement equipment were prepared, and in the communication protocol, two-wheeled vehicle-related matters were newly composed in the vehicle classification code and violation items to develop standards.

• Journal of Korean Neurosurgical Society
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• v.66 no.4
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• pp.456-464
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• 2023

Objective : This study aims to investigate the incidence of vestibular schwannoma (VS) and demographic characteristics in Korea using population-based National Health Insurance Service data. Methods : This study analyzed Korean National Health Insurance Service data from 2005 to 2020, based on the International Classification of Diseases, 10th version, Clinical Modification codes D333 and D431. Only those patients who had undergone magnetic resonance imaging and audiologic tests were considered definitive cases. Demographic variables included age, sex, treatment modality, hypertension, diabetics, dyslipidemia, smoking history, alcohol history, and income status. Results : The total number of VS patients was 5751. The average incidence rate was 0.71 per 100000 from 2005 to 2020, and the annual incidence rate increased from 0.33 in 2005 to 1.32 in 2019 but decreased to 0.80 in 2020. Incidence was highest in those aged 60-69 years (1.791) and lowest in those younger than 20 years (0.041). Incidence was higher in females, and the number of patients who received radiosurgery (46.64%) was largest compared to the wait and scan group (37.96%), microsurgery group (12.85%), or the group who received both (2.56%). Diabetes, dyslipidemia, and alcohol consumption increased the risk of VS, while cigarette smoking reduced the risk of VS. Conclusion : The incidence of VS exhibited an increasing trend from 2005 to 2019. Radiosurgery (46.64%) was the most common treatment modality. Diabetes, dyslipidemia, and alcohol consumption increased the risk of VS, while cigarette smoking reduced the risk of VS.

• Journal of the Korea Society of Computer and Information
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• v.28 no.11
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• pp.53-63
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• 2023

This study developed a cognitive impairment predictive model as one of the screening tests for preventing dementia in the elderly by using Automated Machine Learning(AutoML). We used 'Wearable lifelog data for high-risk dementia patients' of National Information Society Agency, then conducted using PyCaret 3.0.0 in the Google Colaboratory environment. This study analysis steps are as follows; first, selecting five models demonstrating excellent classification performance for the model development and lifelog data analysis. Next, using ensemble learning to integrate these models and assess their performance. It was found that Voting Classifier, Gradient Boosting Classifier, Extreme Gradient Boosting, Light Gradient Boosting Machine, Extra Trees Classifier, and Random Forest Classifier model showed high predictive performance in that order. This study findings, furthermore, emphasized on the the crucial importance of 'Average respiration per minute during sleep' and 'Average heart rate per minute during sleep' as the most critical feature variables for accurate predictions. Finally, these study results suggest that consideration of the possibility of using machine learning and lifelog as a means to more effectively manage and prevent cognitive impairment in the elderly.

• Restorative Dentistry and Endodontics
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• v.49 no.1
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• pp.4.1-4.9
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• 2024

Objectives: This study aims to correlate caries-causing microorganism load, lactic acid estimation, and blood groups to high caries risk in diabetic and non-diabetic individuals and low caries risk in healthy individuals. Materials and Methods: This study includes 30 participants divided into 3 groups: Group A, High-risk caries diabetic individuals; Group B, High-risk caries non-diabetic individuals; and Group C, Low-risk caries individuals. The medical condition, oral hygiene, and caries risk assessment (American Dental Association classification and International Caries Detection and Assessment System scoring) were documented. Each individual's 3 mL of saliva was analyzed for microbial load and lactic acid as follows: Part I: 2 mL for microbial quantity estimation using nutrient agar and blood agar medium, biochemical investigation, and carbohydrate fermentation tests; Part II: 0.5 mL for lactic acid estimation using spectrophotometric analysis. Among the selected individuals, blood group correlation was assessed. The χ² test, Kruskal-Wallis test, and post hoc analysis were done using Dunn's test (p < 0.05). Results: Group A had the highest microbial load and lactic acid concentration, followed by Groups B and C. The predominant bacteria were Lactobacilli (63.00 ± 15.49) and Streptococcus mutans (76.00 ± 13.90) in saliva. Blood Group B is prevalent in diabetic and non-diabetic high-risk caries patients but statistically insignificant. Conclusions: Diabetic individuals are more susceptible to dental caries due to high microbial loads and increased lactic acid production. These factors also lower the executing tendency of neutrophils, which accelerates microbial accumulation and increases the risk of caries in diabetic individuals.

• Korean Journal of Head & Neck Oncology
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• v.40 no.1
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• pp.1-5
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• 2024

The Bethesda System for Reporting Thyroid Cytopathology (TBSRCT) is crucial for cytopathologists to use a standardized, category-based reporting system for thyroid fine needle aspirations and is effective for clear communication with the referring physicians. The new Bethesda System for Reporting Thyroid Cytopathology, the third edition in 2023, provides several key updates. The most important update is the assignment of only single name for each of the six diagnostic categories: (I) nondiagnostic; (II) benign; (III) atypia of undetermined significance; (IV) follicular neoplasm; (V) suspicious for malignancy; and (VI) malignant. An implied risk of malignancy (ROM) for each of six categories has been updated based on extensively published data since the second edition of TBSRTC in 2017 and offers both an average ROM for each category and the expected range of cancer risk. Estimated final ROM after excluding "Noninvasive Follicular Thyroid Neoplasm with Papillary Like Nuclear Features (NIFTP)" for each of six categories has been updated based on the reported mean decreases in the ROM if excluding NIFTP. For atypia of undetermined significance (AUS) category, the subcategorization is simplified and more formalized into 2 subgroups, AUS-nuclear atypia or AUS-other, based on the implied ROM and molecular profiling. For the pediatric thyroid disease, pediatric ROMs and management algorithms are newly added for the same six reporting categories for this age group. New or revised disease nomenclatures including high-grade follicular-derived carcinoma has been updated according to the recently published 2022 World Health Organization Classification of Thyroid Neoplasms. Brand new two chapters are added including clinical perspectives and imaging studies (Chap. 13) and the use of molecular and other ancillary tests (Chap. 14). The atlas is updated with new images to illustrate more effectively for new disease entity and diagnostic criteria.

• Structural Engineering and Mechanics
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• v.89 no.6
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• pp.617-626
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• 2024

The study investigated the behavior of plain and fibered Ultra-High Performance Concrete (UHPC) beams under varying loading conditions using integrated analysis of the flexure and acoustic emission tests. The loading rate of testing is -0.25 -2 mm/min. It is observed that on increasing loading rate, flexural strength increases, and toughness decreases. The acoustic emission testing revealed that higher loading rates accelerate crack propagation. Fiber effect and matrix cracking are identified as significant contributors to the release of acoustic emission energy, with fiber rupture/failure and matrix cracking showing rate-dependent behavior. Crack classification analysis indicated that the rise angle (RA) value decreased under quasi-static loading. The average frequency (AF) value increased with the loading rate, but this trend reversed under rate-dependent conditions. K-means analysis identified distinct clusters of crack types with unique frequency and duration characteristics at different loading rates. Furthermore, the historic index and signal strength decreased with increasing loading rate after peak capacity, while the severity index increased in the post-peak zone, indicating more severe damage. The sudden rise in the historic index and cumulative signal strength indicates the possibility of several occurrences, such as the emergence of a significant crack, shifts in cracking modes, abrupt failure, or notable fiber debonding/pull-out. Moreover, there is a distinct rise in the number of AE knees corresponding to the increase in loading rate. The crack mapping from acoustic emission testing aligned with observed failure patterns, validating its use in structural health monitoring.

• Tuberculosis and Respiratory Diseases
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• v.58 no.6
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• pp.570-575
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• 2005

Introduction : Diffuse interstitial lung diseases (DILD) comprise of a large group of lung diseases with diverse etiologies. They are classified into four categories based on the etiology and pathological findings. In Korea, epidemiological data on DILD has never been reported in a prospective manner. Method : From May 2002 to April 2004, total 487 patients with DILD were prospectively registered at Samsung Medical Center. The prospective observational analysis of the etiologies, its classification based on 2002 ATS/ERS (American Thoracic Society/European Respiratory Society) guidelines, as well as diagnostic tests and the retrospective analysis of the treatment modalities were carried out. Any infectious and malignant causes were excluded. Results : 1) The patients were classified into idiopathic interstitial pneumonia (IIP) in 269 patients (55.2%), known causes of DILD in 168 patients (34.5%), sarcoidosis in 27 patients (5.5%), other forms of DILD in 14 patients (2.9%), and undetermined DILD in 9 patients (1.9%). 2) The diagnostic test showed that most patients had undergone chest high resolution computed tomography (HRCT) and pulmonary function test (PFT) (97%, 89%). Transbronchial lung biopsy (TBLB) and surgical lung biopsy (SLB) were performed in limited patients (38%, 29%). 3) Among 269 patients with IIP, 220 (82%) had idiopathic pulmonary fibrosis (IPF) while 23 (9%) had nonspecific interstitial pneumonia. SLB was carried out in 36% of patients with IIP. 4) Symptomatic supportive care was given to 67% of IPF, but specific medical treatment including corticosteroids was administered to 89% of non-IPF patients. Conclusion : A nationwide registry of DILD patients is required to determine the annual incidence, etiology, and practice pattern of diagnosis and treatment in Korea.

• Clinical and Experimental Pediatrics
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• v.49 no.11
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• pp.1158-1166
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• 2006

Purpose : The purpose of this study is to make a diagnostic classification and discuss a diagnostic strategy of floppy infants by investigating clinical, neurological, electrophysiological, and genetic analysis of infants admitted to intensive care units with the complaint of hypotonia. Methods : A retrospective study was performed from Jan. 1993 to Dec. 2005 in neonatal and pediatric intensive care units of Seoul National University Children's Hospital. Clinical features and all tests related to hypotonia were investigated. Results : There were 21 cases of floppy infants admitted to intensive care units. Final diagnosis was classified as centra (7 cases[33.3 percent]), peripheral (11 cases [52.4 percent]), and unspecified (3 cases [14.3 percent]). Among the central group, three patients were diagnosed as hypoxic ischemic encephalopathy, two patients as Prader-Willi syndrome, one patient as chromosomal disorder, and one patient as transient hypotonia. Among the peripheral group, four patients were diagnosed as myotubular myopathy, three patients as SMA type 1, two patients as congenital myotonic dystrophy, one patient as congenital muscular dystrophy, and one as unspecified motor-neuron disease. Motor power was above grade 3 on average, and deep tendon reflex was brisk in the central group. Among investigations, electromyography showed 66 percent sensitivity in the peripheral group, and muscle biopsy was all diagnostic in the peripheral group. Brain image was diagnostic in the central group, and Prader-Willi FISH or karyotyping was helpful in diagnosis in central group. Morbidity and mortality was more severe in the peripheral group Conclusion : Classification of diagnosis by clinical characteristics in this study, and application of investigations step by step, may provide an effective diagnostic strategy.

• Clinical and Experimental Pediatrics
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• v.46 no.9
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• pp.883-888
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• 2003

Purpose : The etiology of hemolytic anemia can be classified as either cellular or extracellular defects of red blood cells. The aim of this study was to investigate the clinical and laboratory findings of hemolytic anemia concerning its etiological classification. Methods : Clinical and laboratory findings of the patients with hemolytic anemia treated from January 1987 to May 2002 at Severance Hospital were analyzed retrospectively. They were divided into two groups based on the types of red cell defects(group I : erythrocytic defect, group II : extraerythrocytic defect). Results : Twenty one cases were included in group I, thirty four cases in group II, and three cases were unclassified. In group I, nineteen cases(90.5%) were diagnosed as hereditary spherocytosis and were proved to have red cell membrane disorders while two cases(9.5%) were shown to have red cell enzyme deficiencies. In group II, thirteen cases(38.2%) were noted as autoimmune hemolytic anemia, eleven cases(32.4%) as traumatic or microangiopathic hemolytic anemia, four cases(11.8%) as drug induced hemolytic anemia, two cases(5.9%) were related with systemic lupus erythematosus and one case(2.9%) with malignancy. Hemoglobin at the time of diagnosis(7.5 g/dL vs. 6.2 g/dL, P<0.05) and the incidence of splenomegaly(85.7% vs. 18.2%, P<0.05) were higher in group I though blood urea nitrogen(9.0/0.4 mg/dL vs. 27.8/1.6 mg/dL, P<0.05) was higher in group II. Conclusion : Comparing the clinical features of pediatric hemolytic anemia, we concluded as following : In cases associated with extraerythrocytic defect, blood tests revealed significant initial lower hematocrit with higher level of BUN and Cr while cases with erythrocytic defect, splenomegaly were more common noted.