• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.697-702
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• 2023

Recently, with the introduction of drones, a core technology of the 4th industrial revolution, various convergence education using drones is being conducted in school education sites. In particular, drone theory and practice education is being conducted in connection with free semester classes and career exploration. The drone convergence education program has higher learner satisfaction than simple demonstration and practice education, and the learning effect is high due to direct practical experience. However, since practical education is being conducted for a large number of learners, it is impossible to restrict and control the flight of a large number of drones in a limited place. In this paper, we propose a monitoring system that allows the instructor to monitor multiple drones in real time and learners to recognize collisions between drones in advance when multiple drones are operated, focusing on education operated in schools. The communication module used in the experiment was equipped with GPS in Murata LoRa, and the server and client were configured to enable monitoring based on the location data received in real time. The performance of the proposed system was evaluated in an open space, and it was confirmed that the communication signal was good up to a distance of about 120m. In other words, it was confirmed that 25 educational drones can be controlled within a range of 240m and the instructor can monitor them.

• Journal of Surface Science and Engineering
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• v.56 no.2
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• pp.147-151
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• 2023

Transparent ZnO (100 nm thick) and ZnO/Ti/ZnO (ZTZ) films were prepared with radio frequency (RF) and direct current (DC) magnetron sputtering on the glass substrate at room temperature. During the ZTZ film deposition, the thickness of the Ti interlayer was varied, such as 6, 9, 12, and 15 nm, while the thickness of ZnO films was kept at 50 nm to investigate the effect of the Ti interlayer on the crystallization and opto-electrical performance of the films. From the XRD pattern, it is concluded that the 9 nm thick Ti interlayer showed some characteristic peaks of Ti (200) and (220), and the grain size of the ZnO (002) enlarged from 13.32 to 15.28 nm as Ti interlayer thickness increased. In an opto-electrical performance observation, ZnO single-layer films show a figure of merit of 1.4×10^-11 Ω^-1, while ZTZ films with a 9 nm-thick Ti interlayer show a higher figure of merit of 2.0×10^-5 Ω^-1.

• Journal of the Korean Geotechnical Society
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• v.22 no.8
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• pp.107-118
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• 2006

Among a variety of influencing components, time-variant seepage and long-term underground motion are important to understand the abnormal behavior of tunnels. Excessiveness of these two components could be the direct cause of severe damage on tunnels, however, it is not easy to quantify the effect of these on the behavior of tunnels. These parameters can be estimated by using inverse methods once the appropriate relationship between inputs and results is clarified. Various inverse methods or parameter estimation techniques such as artificial neural network and least square method can be used depending on the characteristics of given problems. Numerical analyses, experiments, or monitoring results are frequently used to prepare a set of inputs and results to establish the back analysis models. In this study, a back analysis method has been developed to estimate geotechnically hard-to-known parameters such as permeability of tunnel filter, underground water table, long-term rock mass load, size of damaged zone associated with seepage and long-term underground motion. The artificial neural network technique is adopted and the numerical models developed in the first part are used to prepare a set of data for learning process. Tunnel behavior, especially the displacements of the lining, has been exclusively investigated for the back analysis.

• East European & Balkan Studies
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• v.32
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• pp.257-281
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• 2012

Are the policies and strategies which weak and small states choose to follow for ensuring their's own security meaningless? Can the fate of weak states be guaranteed only by the neighboring benign strong states and be in certain international relations favoring for them? In this paper, to answer these questions, what kinds of security policies and foreign policies had small states chosen which were in the face of threats of great powers will be examined. Between the two world war, the series of event which took place in central and eastern European countries(CEEc) have been selected to examine the hypothesis and theories of international relations and foreign policies, and at the same time cited as examples of failed foreign policy and security strategy. During interwar periods, CEEc were the prime examples for examining what kind of policies and strategies had the small states chosen over the international relations in which the smalls had to struggle to survive between neighbouring the powers and between the hostiles. Furthermore, for the measures which the smalls had chosen had no effect when the great power threatened military to them, the main purpose of this paper is to examine what was the best choose to depend their survival. For this purpose, in this paper, several strategies which the smalls can choose and the counterfactuals, that is "if the smalls chosen another strategies, they could...", will be examined.

• Korean small business review
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• v.41 no.3
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• pp.107-128
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• 2019

The Employment Permit System (EPS), a system of bringing in low-skilled foreign workers, has been implemented since 2004 to relieve labor shortages in SMEs. Despite the increasing number of foreign workers under this system, due to lack of research we have very limited managerial understanding. Moreover, previous studies focused on economic or legal perspectives, which calls for a different perspective of business and management. In this study, we examined how to foster organizational citizenship behaviors (OCB) of low-skilled immigrant workers at the workplace by integrating two analytical frames-social support from management studies and cultural adjustment from immigrant literature. We tested our model using a sample of 661 immigrant workers from 11 countries working in Korea. Our results indicated that, social support perception triggered not only a direct effect on organizational citizenship behaviors of immigrant workers but also indirect effects via the level of cultural adaptation. Our findings indicated that two views are all meaningful in explaining OCB of immigrants, and provided practical implications to SMEs using EPS.

• The Journal of Internal Korean Medicine
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• v.44 no.3
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• pp.485-505
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• 2023

Objective: The purpose of this study is to assess the effectiveness and safety of using Taeksa-tang for dyslipidemia through a systematic review and meta-analysis of randomized controlled trials (RCTs). Methods: The search was conducted using keywords such as "dyslipidemia", "hyperlipidemia", "taeksa tang", "zexie tang", and "takusha to" in 12 databases (Pubmed, Cochrane, Embase, ScienceDirect, CNKI, Wanfang, CiNii, RISS, KISS, ScienceON, OASIS, and DBpia) on April 13, 2023. There were no limits on the publication period and language. Cochrane's risk of bias (RoB) was used to evaluate the quality of the studies. A meta-analysis was conducted according to the outcome measurements such as total effective rate (TER), total cholesterol (TC), triglyceride (TG), HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C), and adverse effects, using the Review Manager web. Results: A total of 9 RCTs were selected. In evaluating the RoB, 2 studies mentioning the random sequence generation, 1 study conducting double blindness, and 8 studies without missing values were evaluated as low risk, while 1 study without mentioning the random sequence generation was evaluated as high risk. All other parts were evaluated as unclear risk. The treatment group (Taeksa-tang or Taeksa-tang-gagam) showed more statistically significant effects compared to the control group (Western medicine or Chinese patent medicine) in TER (RR : 1.24, 95% CI 1.15 to 1.34, P<0.00001), TC (MD : -1.12, 95% CI -1.68 to -0.56, P<0.0001), TG (MD : -1.08, 95% CI -1.65 to -0.51, P=0.0002), HDL-C (MD : 0.63, 95% CI 0.34 to 0.93, P<0.0001), LDL-C (MD : -0.81, 95% CI -1.10 to -0.53, P<0.00001). In addition, the treatment group showed lower adverse effects compared to the control group (RR : 0.30, 95% CI 0.12 to 0.74, P=0.008). Conclusion: This study suggests that Taeksa-tang is effective and safe to use for treating dyslipidemia. However, due to the low quality of the included studies, more clinical studies need to be conducted in the future to increase the possibility of clinical use.

• Journal of the Korean Geotechnical Society
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• v.39 no.7
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• pp.17-30
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• 2023

This study investigates the impact of water immersion and high temperature on the shear strength of cemented sand through direct shear tests. Standard Jumunjin sand was used and cemented with binders, such as ultra-rapid hardening cement and an epoxy aqueous solution. The binder was mixed at concentrations of 4%, 8%, or 12%. Subsequently, cylindrical cemented specimens with a diameter of 64 mm and height of 25 mm were produced using compaction. The curing period was three days, and the specimens were cured under dry air, immersion, and heating conditions. The heating condition involved subjecting the immersed specimens to a microwave oven three times for three minutes to achieve an internal temperature of approximately 90℃. Regardless of the binder type, the cohesion of the cemented sand increased with higher binder content, whereas the internal friction angle exhibited a slight increase or decrease. Compared with ultra-rapid hardening cemented sand, epoxy-cemented sand displayed an average cohesion that was five times higher and an internal friction angle that was 10° higher. Overall, irrespective of binder type, the shear strength decreased during water immersion and increased during heating. Notably, the epoxy-cemented sand exhibited a three-fold increase in cohesion and a more than 20° increase in the internal friction angle during heating.

• Therapeutic Science for Rehabilitation
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• v.11 no.1
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• pp.21-33
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• 2022

Purpose : The purpose of this study was to establish scientific evidence though a systematic review, of the existing interventional methods and their respective effects, for swallowing disorders among dementia patients. The interventional methods were based on patient characteristics. Methods : An electronic literature search was performed using five electronic databases from 2010 to 2020. The keywords were 'Dementia', 'Alzheimer disease', 'Deglutition disorder', 'Swallowing disorder', 'Dysphagia'. Five articles met the inclusion criteria. Results : One study with moderate-to-severe and four studies with severe dementia patients were included. The interventions consisted of one remedial intervention, three compensatory interventions, and one comprehensive intervention. Compensatory intervention, including behavioral and psychological management, were used in moderate-to-severe patients. For the severe patients, remedial, compensatory, and comprehensive intervention were used to address the feeding tube problem. The interventions used in each study had a positive effect on the outcome variables associated with swallowing ability. Conclusion : The purpose of the intervention and the intervention factors changed depending on the patient's dementia stage. The intervention was effective when considering the progressive stage of the patient. These results may serve as a guide in designing effective interventions for swallowing disorders in dementia patients.

• 한국노년학
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• v.31 no.3
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• pp.653-672
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• 2011

The present study empirically confirmed Korean elder's four major pains consisted of poverty, disease, role loss, loneliness and investigated the mediating role of depression between the four major pains and the elder's suicidal thought. To investigate the cause and effect of factors, we conveniently collected 309 samples from 16 Gyungrodangs evenly located in Jeonju and 291 samples, survived the data cleaning such as missing values, outliers, normality and covariance conditions, were analyzed by frequency, factor analysis, reliability, confirmatory factor analysis and structural model analysis. Followed were the selected contributions of the present study. First, the constructs of four major pains such as poverty, disease, role loss, loneliness were predictors of suicidal thought mediated by depression. Second, the elder's poverty, that was the heaviest factor of the four major pain constructs, was a predictor of role loss leading to loneliness. Third, four major pains were predictors of the elder's depression. Note that poverty were not direct but indirect predictor of depression. The present study confirmed the concept of four major pains. Also those who practice in the area of the elderly care should consider the four major pains as well as depression while intervening in the elderly's suicidal thought.

• 한국노년학
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• v.30 no.4
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• pp.1163-1177
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• 2010

This study was conducted to establish the appropriate facilities criteria of the Korean welfare devices center. We e-mail surveyed 194 welfare devices centers and analysed 13 blueprints of them. We established the following proper principles of facilities. First, consist type and area of room should depend on the type of welfare devices centers. Second, The flow of human and welfare devices should be simple. Third, the area calculated on the base of intent of center owner and the size of beds, wheelchairs, etc. Fourth, exhibit room facing with roadside may obtain advertising effect. Fifth, the storage and disinfecting room should use different entrance, and avoid the intersection of flow to prevent cross-contamination. Sixth, the access road to the exhibition and consulting room should be able to approach by the wheelchair. seventh, office room should be invisible to keep customer's privacy. Direct Cleaning-disinfecting type center on the premise that the maximum 165m², middle 150m², intermediate 140m², display at least Consultation, Cleaning-disinfecting room, storage (clean, contaminated), the office, equipped with a parking space. Entrust Cleaning-disinfecting type center on the premise that a maximum 134m², middle 119m², intermediate 109m² exhibited minimal activity room, consultation room, office, equipped with a parking space, collecting welfare when importing equipment warehouse (clean, pollution) have been proposed to equip up to.