• Women's Health Nursing
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• v.20 no.1
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• pp.14-28
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• 2014

Purpose: This study was to identify relationships of maternal psychosocial factors including mother's mood state, childcare stress, social support and sleep satisfaction with breastfeeding adaptation and immune substances in breast milk, especially secretory immunoglobulin A (sIgA) and transforming growth factor-beta 2 (TGF-${\beta}2$). Methods: Data were collected from 84 mothers who delivered full-term infants by natural childbirth. Structured questionnaires and breast milk were collected at 2~4 days and 6 weeks postpartum. Data were analyzed using descriptive statistics, Pearson's correlation, multiple linear regression, and generalized estimating equation (GEE). Results: Scores for the breastfeeding adaptation scale were significantly related with child care stress, mood state and social support. Mother's anger was positively correlated with the level of sIgA in colostrum (p<.01). Immune substances of breastmilk was significantly influenced by time for milk collection (p<.001) and the type of breastfeeding (sIgA, p<.001, TGF-${\beta}2$, p=.003). Regression analysis showed that breastfeeding adaptation could be explained 59.1% by the type of breastfeeding, childcare stress, the Profile of Mood States, emotional support and sleep quality (F=16.67, p<.001). Conclusion: The findings from this study provide important concepts of breastfeeding adaptation program and explanation of psychosocial factors by immune substances in breast milk. Future research, specially, bio-maker research on breast milk should focus on the ways to improve breastfeeding adaptation.

• Smart Structures and Systems
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• v.18 no.3
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• pp.405-423
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• 2016

In this study, the feasibility of using telecommunication single-mode optical fiber (SMF) as a distributed fiber optic strain and crack sensor was evaluated in concrete pavement monitoring. Tensile tests on various sensors indicated that the $SMF-28e^+$ fiber revealed linear elastic behavior to rupture at approximately 26 N load and 2.6% strain. Six full-scale concrete panels were prepared and tested under truck and three-point loads to quantify the performance of sensors with pulse pre-pump Brillouin optical time domain analysis (PPP-BOTDA). The sensors were protected by precast mortar from brutal action during concrete casting. Once air-cured for 2 hours after initial setting, half a mortar cylinder of 12 mm in diameter ensured that the protected sensors remained functional during and after concrete casting. The strains measured from PPP-BOTDA with a sensitivity coefficient of $5.43{\times}10^{-5}GHz/{\mu}{\varepsilon}$ were validated locally by commercial fiber Bragg grating (FBG) sensors. Unlike the point FBG sensors, the distributed PPP-BOTDA sensors can be utilized to effectively locate multiple cracks. Depending on their layout, the distributed sensors can provide one- or two-dimensional strain fields in pavement panels. The width of both micro and major cracks can be linearly related to the peak strain directly measured with the distributed fiber optic sensor.

• Journal of Trauma and Injury
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• v.34 no.3
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• pp.162-169
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• 2021

Purpose: For severe lung injuries or acute respiratory distress syndrome that occurs during critical care due to trauma, extracorporeal membrane oxygenation (ECMO) may be used as a salvage treatment. This study aimed to describe the experiences at a single center with the use of ECMO in trauma patients. Methods: We enrolled a total of 25 trauma patients who were treated with ECMO between January 2015 and December 2019 at a regional trauma center. We analyzed and compared patients' characteristics between survivors and non-survivors through a medical chart review. We also compared the characteristics of patients between direct and indirect lung injury groups. Results: The mean age of the 25 patients was 45.9±19.5 years, and 19 patients (76.0%) were male. The mean Injury Severity Score was 26.1±10.1. Ten patients (40.0%) had an Abbreviated Injury Scale (AIS) 3 score of 4, and six patients (24.0%) had an AIS 3 score of 5. There were 19 cases (76.6%) of direct lung injury. The mortality rate was 60.0% (n=15). Sixteen patients (64.0%) received a loading dose of heparin for the initiation of ECMO. There was no significant difference in heparin use between the survivors and non-survivors (70% in survivors vs. 60% in non-survivors, p=0.691). When comparing the direct and indirect lung injury groups, there were no significant differences in variables other than age and ECMO onset time. Conclusions: If more evidence is gathered, risk factors and indications will be identified and we expect that more trauma patients will receive appropriate treatment with ECMO.

• Healthcare Informatics Research
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• v.24 no.4
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• pp.381-386
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• 2018

Objectives: This study aimed to describe the process of utilizing a mobile application for ecological momentary assessment (EMA) to collect data on stress and mood in daily life setting. Methods: A mobile application for the Android operating system was developed and installed with a set of questions regarding momentary mood and stress into a smartphone of a participant. The application sets alarms at semi-random intervals in 60-minute blocks, four times a day for 7 days. After obtaining all momentary affect and stress, the questions to assess the usability of the mobile EMA application were also administered. Results: The data were collected from 97 police officers working in Gyeonggi Province of South Korea. The mean completion rate was 60.0% ranging from 3.5% to 100%. The means of positive and negative affect were 18.34 of 28 and 19.09 of 63. The mean stress was 17.92 of 40. Participants responded that the mobile application correctly measured their affect ($4.34{\pm}0.83$) and stress ($4.48{\pm}0.62$) of 5-point Likert scale. Conclusions: Our study investigated the process of utilizing a mobile application to assess momentary affect and stress at repeated times. We found challenges regarding adherence to the research protocol, such as completion and delay of answering after alarm notification. Despite this inherent issue of adherence to the research protocol, the EMA still has advantages of reducing recall bias and assessing the actual moment of interest at multiple time points that improves ecological validity.

• Earthquakes and Structures
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• v.20 no.1
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• pp.109-122
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• 2021

Significant progress in the oil and gas industry advances the application of pipeline into an intelligent era, which poses rigorous requirements on pipeline safety, reliability, and maintainability, especially when crossing seismic zones. In general, strike-slip faults are prone to induce large deformation leading to local buckling and global rupture eventually. To evaluate the performance and safety of pipelines in this situation, numerical simulations are proved to be a relatively accurate and reliable technique based on the built-in physical models and advanced grid technology. However, the computational cost is prohibitive, so one has to wait for a long time to attain a calculation result for complex large-scale pipelines. In this manuscript, an efficient and accurate surrogate model based on machine learning is proposed for strain demand prediction of buried X80 pipelines subjected to strike-slip faults. Specifically, the support vector regression model serves as a surrogate model to learn the high-dimensional nonlinear relationship which maps multiple input variables, including pipe geometries, internal pressures, and strike-slip displacements, to output variables (namely tensile strains and compressive strains). The effectiveness and efficiency of the proposed method are validated by numerical studies considering different effects caused by structural sizes, internal pressure, and strike-slip movements.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.16 no.1
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• pp.71-77
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• 2006

Several network attacks, such as distributed denial of service (DDoS) attack, present a very serious threat to the stability of the internet. The threat posed by network attacks on large networks, such as the internet, demands effective detection method. Therefore, a simple intrusion detection system on large-scale backbone network is needed for the sake of real-time detection, preemption and detection efficiency. In this paper, in order to discriminate attack traffic from legitimate traffic on backbone links, we suggest a relatively simple statistical measure, entropy, which can track value frequency. Den is conspicuous distinction of entropy values between attack traffic and legitimate traffic. Therefore, we can identify what kind of attack it is as well as detecting the attack traffic using entropy value.

• Journal of Korean Academy of Nursing
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• v.51 no.3
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• pp.294-304
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• 2021

Purpose: This study aimed to investigate objectively measured physical activity (PA) in institutionalized older adults with mild cognitive impairment (MCI) and to elucidate the influence of autonomic nervous function, salivary cortisol, and PA on cognitive functions based on neurovisceral integration model. Methods: Overall cognitive function was evaluated using the mini-mental state examination (MMSE) and executive function was evaluated using semantic verbal fluency test and clock drawing test. Actigraph for PA, HRV and sAA for autonomous function, and the geriatric depression scale for depression were used. Saliva specimens were collected in the morning for sAA and cortisol. Results: Ninety-eight older adults from four regional geriatric hospitals participated in the study. They took 4,499 steps per day on average. They spent 753.93 minutes and 23.12 minutes on average in sedentary and moderate-to-vigorous activity, respectively. In the multiple regression analysis, lower salivary cortisol level (β = - .33, p = .041) and greater step counts (β = .37, p = .029) significantly improved MMSE score. Greater step count (β = .27, p = .016) also exerted a significant influence on verbal fluency, and greater sAA (β= .35, p = .026) was significantly associated with a better clock drawing test result. Conclusion: Salivary cortisol, sAA and physical activity were significantly associated with cognitive functions. To prevent older adults from developing dementia, strategies are needed to increase their overall PA amount by decreasing sedentary time and to decrease salivary cortisol for cognitive function, and to maintain their sympathetic nervous activity for executive function.

• Journal of Physiology & Pathology in Korean Medicine
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• v.35 no.5
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• pp.162-168
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• 2021

This study was conducted to investigate the current status of online classes and evaluations during the COVID-19 pandemic and the satisfaction of students attending the College of Korean Medicine. A survey was conducted with students enrolled in Dongguk University's College of Korean Medicine. The questionnaire was divided into four areas asking about online lectures, laboratory practice, clinical practice, and evaluation experience. The items were composed of multiple-choice, a 5-point scale, and subjective type. After distributing the Google form address through SNS and LMS, only those who agreed to the questionnaire were responded anonymously. 149 out of 457 enrolled students responded. 98.7% of students experienced online lectures, and more frequently experienced real-time online lectures (98.6%) than recorded lectures (43.5%). Overall satisfaction with online lectures was 3.99 on average. 80.5% of the students experienced the online experiment and practice class, and the overall satisfaction with it was 3.29 on average. 1.3% of students experienced online clinical practice. 86.6% of students experienced online evaluation, and when asked about the fairness of the test, the average score was 3.99. Satisfaction with online lectures and evaluations is generally high, so it is expected to be used as an effective learning tool in the future. However, it seems that facility improvement and technical training of instructors are necessary. In experimental and practical education, the satisfaction level is lower than that of online lectures, so it seems necessary to develop a new online program and to prepare a safe offline education system.

• Journal of Society of Preventive Korean Medicine
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• v.25 no.3
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• pp.57-71
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• 2021

Objectives : Computer-based test (CBT) will be introduced in the national examination of Korean medicine doctors from 2023. This study was aimed to provide some information, including prior considerations, to those preparing for CBT, by presenting a summary of the survey results from participants in a CBT simulation test. Methods : In December 2020, applicants from the graduating class of the college of Korean medicine from four universities participated in the simulation test for CBT. An online anonymous survey on the applicants' preference for CBT versus paper-based tests (PBT) was conducted. The questionnaire consisted of multiple-choice questions on a 5-point Likert scale and free-form questions. Results : A total of 176 students responded to the survey. Their response to CBT was generally positive. The item with the highest agreement was that it should provide a sufficient opportunity to experience CBT in the undergraduate exam (4.38±0.839). Concerns about the possibility of cheating or poor concentration were also detected. In addition to guaranteeing the stability of the CBT system, there were many comments expressing the need to supplement functions within the CBT system, including the memo or highlighter function. Conclusions : This study confirmed the feasibility of CBT including multimedia questions in the field of Korean medicine education and identified overall positive responses from those who experienced the CBT simulation test. Although time is short and there is so much to prepare, we hope this will be a leap forward for effective educational innovation in line with the changing environment of the health care education field.

• Journal of Forest and Environmental Science
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• v.38 no.4
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• pp.239-248
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• 2022

Forestry crane work in a forest harvester or forwarder is regarded as one of most hard work requiring a very high level of operation skill. The operator must handle two or more multi-axes joysticks simultaneously to control the multiple manipulators for maneuvering the crane-tip to its intended location. This study has been carried out to develop a crane-tip controller which can intuitively maneuver the crane-tip, resulting in improving the productivity by decreasing the technical difficulty of control as well as reducing the workload. The crane-tip controller consists of a single 2-axis joystick and a control algorithm run on microcontroller. Lab-scale forestry crane was constructed using electric cylinders. The crane-tip control algorithm has the crane-tip follow the waypoints generated on the given path considering the dead band region using LBO (Lateral Boundary Offset). A speed control gain to change the speed of relevant cylinders relatively is applied as well. By the P (Proportional) control within the control interval of 20 msec, the average error of crane-tip control on the predefined straight path turned out to be 14.5 mm in all directions. When the joystick is used the waypoints are generated in real time by the direction signal from the joystick. In this case, the average error of path control was 12.4 mm for straight up, straight forward and straight down movements successively at a certain constant speed setting. In the slant movement of crane-tip by controlling two axes of joystick simultaneously, the movement of crane-tip was controlled in the average error of 15.9 mm when the crane-tip is moved up and down while moving toward forward direction. It concluded that the crane-tip control was possible using the control algorithm developed in this study.