• Journal of Internet Computing and Services
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• v.24 no.1
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• pp.1-7
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• 2023

Recently, the technology of device-to-device(D2D) communication has been receiving big attention to improve the system performance since the amount of high quality/large capacity data traffic from smart phones and various devices of Internet of Things increase rapidly in 5G/6G based next generation cellular networks. However, even though the system performance of macro cells increase by reusing the frequency, the performance of macro user equipments(MUEs) decrease because of the strong interference from D2D user equipments(DUEs). Therefore, this paper proposes a dynamic channel management(DCM) scheme for DUEs to guarantee the performance of MUEs as the number of DUEs increases in next generation downlink cellular networks. In the proposed D2D DCM scheme, macro base stations dynamically assign subchannels to DUEs based on the interference information and signal to interference and noise ratio(SINR) of MUEs. Simulation results show that the proposed D2D DCM scheme outperforms other schemes in terms of the mean MUE capacity as the threshold of the SINR of MUEs incareases.

• Korean Journal of Community Nutrition
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• v.27 no.6
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• pp.492-502
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• 2022

Objectives: This study examines the foodservice status of kindergartens attached to elementary schools in Seoul. We further determine the perception of elementary school principals and kindergarten assistant principals on the foodservice management for kindergartens. Methods: This survey was conducted from July 17 to 23, 2019, enrolling 207 kindergartens attached to elementary schools in Seoul. Questionnaires were sent to principals of elementary schools and assistant principals of kindergartens, and the data obtained from 89 kindergartens were included in the analysis. The questionnaire consisted of four parts: general information on subjects, foodservice management status, foodservice management status during elementary school vacations, and the perception of principals of elementary schools and assistant principals of kindergartens on foodservice management. Data are presented as frequency and percentage or mean and standard deviation. Statistical comparison between principals of elementary schools and assistant principals of kindergartens was conducted by paired t-test, chi-square test, and Pearson's correlation analysis. Results: A separate menu (10.1%) or recipe (20.2%) that considers preschooler characteristics was rarely used for foodservice at kindergartens attached to elementary schools. Most kindergartens did not have a separate dining space (3.4%) or a dedicated cook (93.3%). Although most kindergartens (92.1%) had operational foodservice during elementary school vacations, non-professional staff and non-nutrition teacher were mainly in charge of organizing the menu and purchasing ingredients (34.1% and 41.5%, respectively). The rate of using a contract catering company (28.0%, 23.2%) was also high. Both elementary school principals and assistant principals of kindergartens showed a high perception of the necessity for providing responsibility allowances for nutrition teachers and improving the cooking environment for kindergartens during elementary school vacations. Conclusions: There is a need for policies and administrative support measures to improve the quality of foodservices for kindergartens attached to elementary schools.

• The Korea Journal of Herbology
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• v.24 no.2
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• pp.13-20
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• 2009

Objectives: To compare the contents of hazardous substances before/after a decoction. Methods : The heavy metal contents before/after a decoction were measured by Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES) and mercury analyzer. In order to analyze pesticides in 6 samples we used simultaneous multi-residue analysis of pesticides by GC/ECD, which was followed by GC/MSD analysis to confirm the identity of the detected pesticide in each sample. In addition, the contents of sulfur dioxide (S02) were performed by Monier-Williams distillation method. Results : 1. The mean values of heavy metal contents (mg/kg) for the samples were as follows: Socheongryong-tang (before decoction - Pb; 1.115, Cd; 0.179, As; 0.069 and Hg; 0.028, after decoction - Pb; 0.110, Cd; 0.011, As; 0.005 and Hg; 0.002), Insampaedok-san (before decoction - Pb; 1.207, Cd; 0.148, As; 0.171 and Hg; 0.026, after decoction - Pb; 0.075, Cd; 0.006, As; not detected and Hg; O.OOD, Oryung-san (before decoction - Pb; 1.955, Cd; 0.430, As; 0.063 and Hg; 0.027, after decoction - Pb; 0.083, Cd; 0.013, As; 0.006 and Hg; 0.002), Hwangryunhaedok-tang (before decoction - Pb; 1.825, Cd; 0.210, As; 0.050 and Hg; 0.009, after decoction - Pb; 0.107, Cd; 0.010, As; 0.005 and Hg; O.OOD, Bangpungtongseong-san (before decoction - Pb; 1.740, Cd; 0.162, As; 0.585 and Hg; 0.018, after decoction - Pb; 0.041, Cd; 0.006, As; 0.022 and Hg; not detected) and Oyaksungi-san (before decoction - Pb; 1.199, Cd; 0.183, As; 0.321 and Hg; 0.031, after decoction - Pb; 0.096, Cd; 0.008, As; 0.021 and Hg; 0.0004). 2. Contents (mg/kg) of sulfur dioxide (S0$_2$) before a decoction in Socheongryong-tang, Insampaedok-san, Oryung-san, Hwangryunhaedok-tang, Bangpungtongseong-san and Oyaksungi-san exhibited 3.2, 5.7, 4.5, 49.8, 7.8 and 22.4, respectively. However, contents of sulfur dioxide after a decoction in all samples were not detected. 3. Contents (mg/kg) of residual pesticides before/after a decoction in all samples were not detected. Conclusions : These results will be used to establish a criterion of heavy metals, residual pesticides and sulfur dioxide.

• Industry Promotion Research
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• v.8 no.3
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• pp.221-230
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• 2023

With the continuous development of higher education, the academic satisfaction of college students has become one of the important indicators to evaluate the quality of education and student development. Therefore, this study aims to explore the role of gender in academic attitude, sincerity, and academic satisfaction of college students in China. The subject of the study was selected by using the purposive sampling method, and data were collected using the survey method. 400 questionnaires were distributed to college students in Guangzhou, China, and 388 questionnaires were used for the final analysis. For statistical analysis, SPSS PC+ Win. ver. 26.0 and SPSS PROCESS macro ver. 4.2 were used, and frequency analysis, reliability analysis, correlation analysis, and conditional indirect effect analysis were performed. The research results are as follows. First, academic attitude had a significant positive correlation with sincerity, gender, and academic satisfaction. Second, gender moderated the intermediary role of academic attitude on academic satisfaction through sincerity. This study indicated that different strategies are needed according to gender to improve academic satisfaction using academic attitude and sincerity of college students. Based on the results, plans to improve the academic satisfaction of college students were suggested.

• Therapeutic Science for Rehabilitation
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• v.11 no.1
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• pp.35-47
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• 2022

Objective : In this study, we conducted a questionnaire survey of occupational therapists to examine their perceptions on and willingness to provide telerehabilitation dementia prevention education. Methods : From March 13 to 19, 2021, a questionnaire survey targeting occupational therapists in Busan, Ulsan, and Gyeongnam was conducted. 100 questionnaires were distributed but only 70 were collected. The collected data were subjected to frequency analysis and descriptive statistics using the statistical program SPSS version 23.0. Results : The average scores by region were as follows. The average compatibility score was highest at 3.92 score, intention to providing education, doctors 3.89 score, community-centric rehabilitation awareness 3.81 score, cost saving 3.78 score, perceiver usefulness 3.75 score, accessibility 3.62 score, the quality of telerehabilitation service was in order of 3.49 score. Conclusion : All items asking whether occupational therapists participate in community-centered rehabilitation and non-face-to-face dementia prevention education programs showed high scores, indicating the willingness to participate actively. In the future, in addition to follow-up research on the implementation of telerehabilitation dementia prevention education, measures for improving accessibility within the local and national government should be discussed.

• 한국노년학
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• v.29 no.4
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• pp.1577-1589
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• 2009

The purpose of this study was to compare the health status, functional status, and home environment hazards by the fear of falling and explore the factors that contribute to the fear of falling. This was a descriptive study. Data were collected for two years with 973 older adults who enrolled in a health center at A city. Trained nurses visited subjects' home and collected data using Resident Assessment Instrument MDS-HC. The average age of the subjects was 76.8 (±7.6) and female was 74.8%. 20.7% of subjects reported fear of falling. In terms of the fear of falling, two groups were compared. There were significant differences in vision, urinary incontinence, pain that interrupts daily activity, unstable gait, comorbidities, frequency of depressive or anxious sign. The greater the age, IADL and ADL dependency, comorbidities, unstabled gait, the more fear of falling. In conclusion, this study reassured the importance of assessing the major factors related to fear of falling such as age, IADL and ADL, comorbities, gait among older adults. This study will contribute to establish strategies for preventing fall. Reducing the fear of falling through the comprehensive nursing intervention will ultimately improve the quality of life in the elderly.

• Korean Journal of Psychosomatic Medicine
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• v.31 no.2
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• pp.72-78
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• 2023

Objectives : This study aims to identify various psychiatric symptoms and psychosomatic symptoms caused by COVID-19 infection and investigate their long-term impact. Methods : A systematic literature review was conducted, selecting papers from domestic and international databases using keywords such as "COVID-19" and "psychosomatic." A total of 16 papers, including those using structured measurement tools for psychosomatic symptoms, were included in the final analysis. Results : Psychiatric symptoms such as anxiety, depression, and somatic symptoms have been reported in acute COVID-19 infection, while long-term post-COVID symptoms include chest pain and fatigue. The frequency of long-term psychosomatic symptoms has been estimated to be 10%-20%. Factors contributing to these symptoms include psychological and social stress related to infectious diseases, gender, elderly age, a history of psychiatric disorders, and comorbid mental illnesses. It is suggested that systemic inflammation, autoimmune responses, and dysregulation of the autonomic nervous system may be involved. Conclusions : Psychosomatic symptoms arising after COVID-19 infection have a negative impact on quality of life and psychosocial functioning. Understanding and addressing psychiatric aspects are crucial for symptom prevention and treatment.

• Journal of Advanced Navigation Technology
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• v.25 no.6
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• pp.536-542
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• 2021

In this paper, we proposed a triple band printed monopole antenna with a bent branch strips for WiFi / 5G. An antenna structure in which bent strips for generating multiple resonance are attached in the form of branches was newly proposed based on a typical monopole strip vertically erected as a triple band antenna structure. The proposed antenna is designed on a FR-4 substrate with dielectric constant 4.3, thickness of 1.6 mm, and size of 28×40 mm². The measured impedance bandwidth is 430 MHz (2.22~2.65 GHz) in the 2.4 GHz WLAN, 450 MHz (3.38~3.83 GHz) in the 3.5 GHz and 2390 MHz (4.95~7.34 GHz), In particular, it has been observed that antenna has a stable omnidirectional radiation patterns as well as gain of 1.537 dBi, 1.878 dBi and 2.337 dBi in the entire frequency band of interest.

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3874-3897
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• 2023

A high-fidelity computational fluid dynamics (CFD) analysis was performed using the Large Eddy Simulation (LES) model for the lower plenum of the High-Temperature Test Facility (HTTF), a ¼ scale test facility of the modular high temperature gas-cooled reactor (MHTGR) managed by Oregon State University. In most next-generation nuclear reactors, thermal stress due to thermal striping is one of the risks to be curiously considered. This is also true for HTGRs, especially since the exhaust helium gas temperature is high. In order to evaluate these risks and performance, organizations in the United States led by the OECD NEA are conducting a thermal hydraulic code benchmark for HTGR, and the test facility used for this benchmark is HTTF. HTTF can perform experiments in both normal and accident situations and provide high-quality experimental data. However, it is difficult to provide sufficient data for benchmarking through experiments, and there is a problem with the reliability of CFD analysis results based on Reynolds-averaged Navier-Stokes to analyze thermal hydraulic behavior without verification. To solve this problem, high-fidelity 3-D CFD analysis was performed using the LES model for HTTF. It was also verified that the LES model can properly simulate this jet mixing phenomenon via a unit cell test that provides experimental information. As a result of CFD analysis, the lower the dependency of the sub-grid scale model, the closer to the actual analysis result. In the case of unit cell test CFD analysis and HTTF CFD analysis, the volume-averaged sub-grid scale model dependency was calculated to be 13.0% and 9.16%, respectively. As a result of HTTF analysis, quantitative data of the fluid inside the HTTF lower plenum was provided in this paper. As a result of qualitative analysis, the temperature was highest at the center of the lower plenum, while the temperature fluctuation was highest near the edge of the lower plenum wall. The power spectral density of temperature was analyzed via fast Fourier transform (FFT) for specific points on the center and side of the lower plenum. FFT results did not reveal specific frequency-dominant temperature fluctuations in the center part. It was confirmed that the temperature power spectral density (PSD) at the top increased from the center to the wake. The vortex was visualized using the well-known scalar Q-criterion, and as a result, the closer to the outlet duct, the greater the influence of the mainstream, so that the inflow jet vortex was dissipated and mixed at the top of the lower plenum. Additionally, FFT analysis was performed on the support structure near the corner of the lower plenum with large temperature fluctuations, and as a result, it was confirmed that the temperature fluctuation of the flow did not have a significant effect near the corner wall. In addition, the vortices generated from the lower plenum to the outlet duct were identified in this paper. It is considered that the quantitative and qualitative results presented in this paper will serve as reference data for the benchmark.

• Korean Journal of Culture and Social Issue
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• v.15 no.1
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• pp.169-186
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• 2009

This study aims to investigate the relationship between personality, especially temperament and subjective well-being. The participants were 681 college students (211 males and 470 females), whose ages ranged from 17 to 37 (M=20.91, SD=2.36). The instruments utilized in the present study were Korean Version of BAS/BIS Scale, The Big Five Locator, Satisfaction with Life Scale, Life Satisfaction Motivation Scale, Life Satisfaction Expectancy Scale, Emotion Frequency Test, and Subjective Happiness Scale. Result indicated that women expected more positive future than men did, while no gender differences were found in any other well-being variables. Correlational analyses revealed that emotional stability and extroversion were closely associated with life satisfaction, happiness, positive and negative emotion, whereas behavioral activation system (BAS) and behavioral inhibition system (BIS) were more closely associated with motivation to live and expectancy of satisfactory life. There was close relationship between conscientiousness and subjective well-being, because they were college students. As a internal factor, personality was better predictor for subjective well-being of female students. For instance, it accounted for around 35% variance of female's subjective happiness. The present findings reiterate the role of personality in quality of life, and it was discussed with characteristics of subjects, situational factors, and previous studies.