• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.773-784
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• 2023

In this study, we developed a dynamic model and steering controller model for an autonomous tractor and evaluated their performance. The traction force was measured using a 6-component load cell, and the rotational speed of the wheels was monitored using proximity sensors installed on the axles. Torque sensors were employed to measure the axle torque. The PI (proportional integral) controller's coefficients were determined using the trial-error method. The coefficient of the P varied in the range of 0.1 - 0.5 and the I coefficient was determined in 3 increments of 0.01, 0.05, and 0.1. To validate the simulation model, we conducted RMS (root mean square) comparisons between the measured data of axle torque and the simulation results. The performance of the steering controller model was evaluated by analyzing the damping ratio calculated with the first and second overshoots. The average front and rear axle torque ranged from 3.29 - 3.44 and 6.98 - 7.41 kNm, respectively. The average rotational speed of the wheel ranged from 29.21 - 30.55 rpm at the front, and from 21.46 - 21.63 rpm at the rear. The steering controller model exhibited the most stable control performance when the coefficients of P and I were set at 0.5 and 0.01, respectively. The RMS analysis of the axle torque results indicated that the left and right wheel errors were approximately 1.52% and 2.61% (at front) and 7.45% and 7.28% (at rear), respectively.

• Clinical and Experimental Vaccine Research
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• v.12 no.4
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• pp.313-318
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• 2023

Purpose: Globally, 25 million children were either unvaccinated or under-vaccinated in year 2021. Among them, India had the highest number of children unvaccinated. Studies have shown impact of coronavirus disease 2019 (COVID-19) pandemic on routine health-care services. Present study aimed to estimate the impact of COVID-19 on utilization of routine immunization services during years 2020 and 2021 in tertiary-care facility. Materials and Methods: Record based descriptive analytic study was conducted at pediatric tertiary-care hospital, Jaipur. Data of children vaccinated as per the National Immunization Schedule for the period January 2019 to December 2021 were retrieved from the immunization records. Doses administered were assessed as a proxy measure of vaccine coverage. The vaccination trends of 2020 and 2021 were compared assuming base year 2019. Unpaired t-test of significance and Pearson correlation was used for correlation analysis. Results: There was significant drop in the vaccine counts after emergence of COVID-19 pandemic. In year 2020 and 2021, mean monthly vaccine count was 2,190±715.1 and 2,305±393.2, respectively, in which maximum drop was in April 2020 (-79.12%) and May 2021 (-57.16%) when it was compared with matched month of base year. There was negative correlation between percent change in vaccine count and COVID-19 cases in 2020 (r=-0.057, p=0.861) and 2021 (r=-0.827, p=0.001) as compared to year 2019. Conclusion: Study concludes that there was a significant gap in utilization of routine immunization services during the COVID-19 pandemic. This necessitates planning and management of routine immunization services in-case of future pandemics to avoid resurgence of vaccine-preventable diseases in the Rajasthan.

• Journal of Yeungnam Medical Science
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• v.41 no.2
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• pp.80-85
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• 2024

Background: This study aimed to compare and evaluate the marginal fit of nanocomposite computer-aided design/computer-aided manufacturing (CAD/CAM) inlays. Three types of nanocomposite CAD/CAM blocks (HASEM, VITA Enamic, and Lava Ultimate) were used as materials. Methods: Class II disto-occlusal inlay restorations were prepared on a typodont mandibular right first molar using diamond rotary instruments. The inlays were fabricated using CAD/CAM technology and evaluated using the silicone replica technique to measure marginal gaps at five locations on each inlay. The data were analyzed by two-way analysis of variance and Tukey post hoc tests (α=0.05). Results: There were no significant differences in the marginal gaps based on the type of nanocomposite CAD/CAM inlay used (p=0.209). However, there was a significant difference in the marginal gaps between the measurement regions. The gingival region consistently exhibited a larger marginal gap than the axial and occlusal regions (p<0.001). Conclusion: Within the limitations of this in vitro study, the measurement location significantly influenced the marginal fit of class II disto-occlusal inlay restorations. However, there were no significant differences in the marginal gaps among the different types of CAD/CAM blocks. Furthermore, the overall mean marginal fits of the class II disto-occlusal inlay restorations made with the three types of nanocomposite CAD/CAM blocks were within the clinically acceptable range.

• Journal of Information Technology Applications and Management
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• v.31 no.1
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• pp.177-188
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• 2024

In this research, a cohort of two children, aged 7-8 years, was selected to participate in a specialized three-week training program aimed at enhancing their working memory. The program consisted of three sessions, each lasting approximately 30 minutes. The primary goal was to investigate the impact and developmental trajectory of working memory in school-aged children. Working memory plays a significant role in young children's learning and daily activities. To address the needs of this demographic, products should offer both educational and enjoyable activities that engage working memory. Digital educational tools, known for their flexibility, are suitable for both older individuals and young children. By updating software or modifying content, these tools can be effectively repurposed for young learners without extensive hardware changes, making them both cost-effective and practical. For example, memory training games initially designed for older adults can be adapted for young children by altering images, music, or storylines. Furthermore, incorporating elements familiar to children, like animals, toys, or fairy tales, can increase their engagement in these activities. Historically, working memory capabilities have been assessed predominantly through traditional intelligence tests. However, recent research questions the adequacy of these behavioral measures in accurately detecting changes in working memory. To bridge this gap, the current study utilized electroencephalography (EEG) as a more sophisticated and precise tool for monitoring potential changes in working memory after the training. The research findings were revealing. Participants showed marked improvement in their performance on n-back tasks, a standard measure for evaluating working memory. This improvement post-training strongly supports the effectiveness of the training program. The results indicate that such targeted and structured training programs can significantly enhance the working memory abilities of children in this age group, providing promising implications for educational strategies and cognitive development interventions.

• 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.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.989-1000
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• 2022

Agricultural operations are performed in uneven environments by attaching an implement on the 3-point hitch of a tractor. A high load is thus placed on the 3-point hitch, and fatigue and failure of the hitch may occur during agricultural operations. In this study, a dynamic simulation model was developed to predict the load occurring on the eyebolt of a 3-point hitch, which is the main damaged component. The simulation model was developed and validated using agricultural data as simulation input and validation data. The dynamics model was developed using the specifications of a 78 kW class tractor. A measurement system was constructed to measure the simulation input and validation data. The simulation model was validated using a traction load on an eye bolt, which was measured during plow tillage operation. The measurement results showed that the average traction load on the left and right lower link and the top link were 8,099.97, 4,943.06, and 636.11 N, respectively. The simulation results and the measured traction load on the left eyebolt were respectively 610.30 and 597.15 N. The simulation results and measured traction load on the left eyebolt were respectively 1,179.78, and 1,145.06 N. The error between the simulation and measurement data was roughly 2% on the left eyebolt and 3% on the right eyebolt.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.537-544
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• 2021

In order to describe the fill-up stages of a near-surface disposal facility vault, a mock-up test is performed, and its behavior during the fil l -up stages is investigated. On an in-site concrete foundation with a l ength of 6600mm, a width of 6600mm and a thickness of 400mm, a reinforced concrete disposal vaul t is manufactured with 4 precast (PC) corner wal l s and 8 PC side wal l s. 36 wasted drums are pl aced on the 1st fl oor in 6 by 6, and then the empty space is fil l ed with grout fil l er. These processes are repeated up to the 5th floor, and the verticality and the joint gaps are measured for each fill-up stage. The verticality is measured using a level at 6 positions on each side wall (3 positions on the left and right sides, respectivel y), i.e. a total of 24 positions on the 4 side wal l s. The joint gaps are measured at 9 positions on each side wal l (3 positions on the left, center and right sides, respectively), I.e. a total 36 positions on the 4 side walls. To measure the joint gaps, crack tips are installed on the left and right sides of every joint gap, and vernier calipers are used. The measured verticality obtained through the mock-up test was found to be ±0.1° based on the initial stage (ST0), and the result of the joint gap was up to 0.38mm. This appears to have a negligible effect on the structure.

• Korean journal of communication and information
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• v.30
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• pp.203-237
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• 2005

The purpose of this study is to find a model that can measure the public relations programs based on the assumption that the public relations should aim to lift the corporate reputation. It is a trend that corporate's activities are to be measured from the standpoint of cost-benefit efficiency. However, public relations fields in Korea is left behind this trend because the fields lack in sophisticated model. In order to fill this gap, the researchers introduce the reputation measurement model that can calculate individual corporate public relations programs. In addition, this reputation model Is applied to Korean companies with the expectation of producing a PR index which ran be used to measure the reputation as corporate asset, or superbrand. This study examines the effects of superbrand on consumers according to the media use. Based on the expert group interviews and surveys on consumers, the factors of reputation are drawn. These factors contribute to find reputation model and measurement index which are again applied to measure the Korean companies' public relations programs. Using superbrand as dependent variables and managing abilities, corporate responsibility, corporate communication, and product/employee quality, this study seeks to find which factor specifically attribute to lift corporate reputation. Results show that each factor influences the corporate reputation positively. In addition, the researchers find that media use is moderately related to the superbrand building process in cognitive dimension.

• Journal of Nutrition and Health
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• v.44 no.6
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• pp.481-487
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• 2011

Obesity not only reduces bone mineral density but also increases inflammatory markers. Therefore, we examined the change in inflammatory markers and morphological microstructure of the bones using a mouse model fed a high-fat diet. C57BL/6J 4-week-old male mice were divided into a control group (n = 6) and a experimental group (n = 6); the control group was provided with 10% Kcal fat diet, and the high-fat diet group was provided with 45% Kcal fat diet for 12 weeks using the free provision method. Blood was analyzed for inflammatory markers, and micro-computed tomography was used to measure the morphological microstructure of the femoral bone. The weight increases in the control group and high-fat diet group were $5.85{\pm}1.84g$ and $16.06{\pm}5.64g$, respectively (p < 0.01), glucose was $115.00{\pm}16.88mg/dL$ and $188.33{\pm}13.29mg/dL$ (p < 0.01), and triglycerides were $65.00{\pm}6.19mg/dL$ and $103.33{\pm}8.02mg/dL$ (p < 0.05) respectively. Leptin and interleukin (IL)-6 were significantly higher in the high-fat diet group than that in the control group (p < 0.01). As a result of a biochemical index analysis of bone metabolism, osteocalcin tended to be lower in the high-fat diet group, whereas CTx was significantly higher in the high-fat diet group compared to that in the control group (p < 0.01). The thickness of the bony trabecula was significantly narrower in the high-fat diet group than that in the control group (p < 0.05), and the gap in the bony trabecula was significantly wider in the high-fat diet group than that in the control group (p < 0.05). IL-6 and the gap in the bone trabecula, which was a morphological microstructure of the bones, showed a positive correlation (p < 0.05). Taken together, inducing obesity through a high-fat diet in mice during the growth phase caused a change in bone microstructure and was correlated with the inflammation index. Accordingly, restriction of excessive fat intake may be needed to suppress the inflammatory reactions and promote normal bone formation.

• Korean journal of communication and information
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• v.43
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• pp.173-208
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• 2008

This study analyses the business performance according to the business diversification of Korean mass media enterprises from year 2003 to 2006. The conclusions drawn which could be divided into five main parts are the followings: First, newspaper companies pursue unrelated diversification in various industrial areas, in order to gain maximum profit while broadcasting companies exert themselves to provide better service by diversifying the major contents. Second, overall the interviewed companies display a constant decline in profit gained from their major business area thus establishing strategies to broaden their focus on diversification of any sort. Third, the researcher completed group analysis in regard of diversification measure resulting in division of three groups. The group which had the most immense diversification range gained the highest ROE, the lowest ROE volatility, and lesser probability of risk taking. The analysis adresses the companies broadening their business areas by researching and focusing on diversification are relatively stable in terms of the profit they gain. Fourth, the middle level group in terms of sales scale, debts, enterprise history, major share rate and high ROE group carry out diversification progressively. The sales scale affects positively to diversification, while the major share rate affects negatively to diversification. Fifth, in accordance to the research, diversification overall contributes to obtainance of successful outcome. Since there was not an immense amount of studies to be referred in the media area, the researcher interviewed and did panel discussion with numerous strategists and managers who are in charge of diversification of media companies. However, collection of only 4 years of data limits the research to be considered to be a generalized study, and does not reflect time gap between business diversification and business performance. Development is required in future studies to be established regarding the media companies' specificity different to other industries, classified the media companies into media types, and consider the time gap in the diversification activities and business performance.