• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.1
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• pp.47-55
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• 2017

As preliminary work for the establishment of a harmonized ship hand signal standard, this paper explores the availability of hand signals as a means of shipboard work communication and considers the validity of standardization. Prior to the feasibility study, shipboard work activities that use hand signals were classified based only on ship safety managers' arbitrary decisions. This survey was carried out to measure shipboard workers' willingness to communicate with hand signals and their preferences regarding the institutional standardization of a hand signal framework if they engage in activities classified as relevant. The results of statistical analysis (a t-test and correlation analysis) showed that respondents are willing to accept harmonized hand signals regardless of both their work type (crew/safety supervisors) and work department (deck/engine room) under working situations where hand signals are an available means of communication. In addition, there was a significant difference in the extent of shipboard workers' frequency of hand signal usages between each type of work activity, indicating a significant positive (+) correlation between frequency of usage and preference for standardization. Finally, it was concluded that shipboard work communication would be effectively improved if a follow-up study is carried out to establish prioritized harmonized hand signal standards for port-related work activities, such as crane operation, windlass/winch operation, line movement/delivery and cargo hold operations.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.38-47
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• 2009

This paper aims to evaluate the freeway traffic management Strategy based on exTMS according to traffic situation of freeway. As freeway user's demands increase, we thus need future-oriented and optimized traffic management. So, through improving the existing system and introducing the advanced system, these systems evaluate for not only preparing the application in real world but also preliminary feasibility. To evaluate effects of the traffic management based on exTMS, in this study, shoulder LCS, advanced VMS(assumption in it is improving next-generation system which it can be offering diverse dynamic traffic information), Ramp-metering system are applicated in simulation. In addition, this study evaluates the effect when all proposed systems are applicated, and compare the individual effect of when independent system is applicated, through considering about traffic condition of V/C=0.5, V/C=0.8, V/C=1.2. The study results show that all assumed cases, the travel speed were improved according to the increasing V/C. Furthermore, the results of evaluated the individual system show that the shoulder LCS was found to be the largest effect, and the effect of VMS(detour rate is 11%) is larger than the other cases.

• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.131-142
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• 2015

The purposes of this study are to develop a measuring instrument for the analysis of science classroom culture from the perspective of Community of Practice (CoP) and to confirm its feasibility. We set the structural factors of CoP and developed preliminary questions through literature review. The validity and reliability of the instrument were examined and modified through the pilot survey participated by a total of 219, 4th, 6th, and 8th grade students. The modified instrument consisted of 5 factors of 'responsibility for learning', 'common interest', 'mutual relationships', 'open participation', and 'practice', comprising a total of 27 items. As the main survey, confirmatory factor analysis and reliability analysis of the instrument were carried out with a total 706 students of the 4th and 6th grade. This measuring instrument was validated and used for analyzing the culture of science classroom CoP of elementary school by comparing the data from the main survey in terms of structural factors, grade, gender, and teacher type. The measuring instrument is expected to be used not only for analyzing science classroom culture from the perspective of CoP, but also for offering implications for the desirable science classroom culture.

• The Journal of Korean Obstetrics and Gynecology
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• v.31 no.1
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• pp.84-98
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• 2018

Objectives: The purpose of this pilot study was to examine the feasibility of recruiting women into a clinical trial designed to examine the effects of acupuncture and electroacupuncture in treating overactive bladder (OAB) in menopause women. We tried to determine if there was preliminary evidence to suggest that acupuncture may be effective in reducing OAB symptoms and improving disease-specific quality of life. We also tried to determine the appropriate treatment duration of OAB, with safety of performing acupuncture and electroacupuncture treatment. Methods: This study was a randomized clinical trial. 7 menopause women were randomly assigned to a electroacupuncture group (EA group) (n=4) or acupuncture group (AC group) (n=3) and received electroacupuncture or acupuncture treatment twice a week (16 sessions) in 8 weeks, and follow up assessment was performed after the end of treatment. Overactive Bladder Symptom Score (OABSS), 3-day bladder diary, and King's Health Questionnaire (KHQ) were performed 4 times (at baseline (visit 0), the middle of treatment (visit 8), after the end of treatment (visit 16), and at 4 weeks of follow-up (visit 17)) and analyzed. 2 subjects were dropped out, and finally 5 subjects completed the study. Statistical analysis was performed using SPSS 18.0 for window program. Results: There was an significant improvement in night-time frequency after the treatment (visit 17) in PP (Per-protocol) group analysis (p=0.042). In additional ITT (Inter-to-treat) group analysis, the OABSS (p=0.042) and night-time frequency (p=p=0.017) were improved significantly after the treatment (visit 17). But there was no significant difference of KHQ before and after the treatment. Also there was no significant difference between EA and AC group after the treatment (visit 16, 17). Conclusions: The results of this pilot study suggested that it was feasible to recruit subjects and perform the study procedures, after reconstructing several details of study protocol in performing further clinical trial.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.9
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• pp.626-636
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• 2009

In Mobile IP-enabled wireless LAN (WLAN), packet flows are corrupted due to the handoff of a mobile node (MN) at the link and network layers, which results in burst packet losses and can cause temporary buffer underflow in a streaming client at the MN. This transient behavior hurts time-sensitive streaming media applications severely. Among many suggestions to address this handoff problem, few studies are concerned with empirical issues regarding the practical validation of handoff options on the time-sensitive streaming media applications. In this paper, targeting seamless streaming over Mobile IP-enabled WLAN, we introduce a seamless media streaming framework that estimates accurate pre-buffering level to compensate the handoff latency. In addition, we propose a link-layer (L2) assisted seamless media streaming system as a preliminary version of this framework. The proposed system is designed to reduce the handoff latency and to overcome the playback disruption from an implementation viewpoint. A packet buffering and forwarding mechanism with L2 trigger is implemented to reduce the handoff latency and to eliminate burst packet losses generated during the handoff. A pre-buffering adjustment is also performed to compensate the handoff latency. The experimental results show that the proposed approach eliminates packet losses during the handoff and thus verify the feasibility of seamless media streaming over Mobile IP-enabled WLAN.

• Journal of Korean Neurosurgical Society
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• v.64 no.6
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• pp.891-900
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• 2021

Objective : Vertebral artery dissecting aneurysm (VADA) is a very rare subtype of intracranial aneurysms; when ruptured, it is associated with significantly high rates of morbidity and mortality. Despite several discussions and debates, the optimal treatment for VADA has not yet been established. In the last 10 years, flow diverter devices (FDD) have emerged as a challenging and new treatment method, and various clinical and radiological results have been reported about their safety and effectiveness. The aim of our study was to evaluate the clinical and radiological results with the use of FDD in the treatment of unruptured VADA. Methods : We retrospectively evaluated the data of all patients with unruptured VADA treated with FDD between January 2018 and February 2021 at our hybrid operating room. Nine patients with unruptured VADA, deemed hemodynamically unstable, were treated with FDD. Among other parameters, the technical feasibility of the procedure, procedure-related complications, angiographic results, and clinical outcomes were evaluated. Results : Successful FDD deployment was achieved in all cases, and the immediate follow-up angiography showed intra-aneurysmal contrast stasis with parent artery preservation. A temporary episode of facial numbness and palsy was noted in one patient; however, the symptoms had completely disappeared when followed up at the outpatient clinic 2 weeks after the procedure. The 3-6 months follow-up angiography (n=9) demonstrated complete/near-complete obliteration of the aneurysm in seven patients, and partial obliteration and segmental occlusion in one patient each. In the patient who achieved only partial obliteration, there was a sac 13 mm in size, and there was no change in the 1-year follow-up angiography. In the patient with segmental occlusion, the cause could not be determined. The clinical outcome was modified Rankin Scale 0 in all patients. Conclusion : Our preliminary study using FDD to treat hemodynamically unstable unruptured VADA showed that FDD is safe and effective. Our study has limitations in that the number of cases is small, and it is not a prospective study. However, we believe that the study contributes to evidence regarding the safety and effectiveness of FDD in the treatment of unruptured VADA.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.4
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• pp.207-218
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• 2019

It is necessary to investigate the efficacy of commercial Korean herbal medicine for cognitive disorder. The purpose of this study is to select candidates among licensed herbal medicines that are expected to be effective in the treatment of cognitive disorders and can be used in future clinical trial. From laboratory experiments, we first found individual single herbal drugs that could be effective for cognitive disorder, and then through experts recommendation, selected five priorities of single herbal drug and obtained the information of the best herb as a combination of each herbal drug. To derive the final herbal prescriptions, we searched the KFDA drug information system for licensed herbal medicines containing each drug and its combination. As a result of laboratory experiments and experts recommendation, we found that the five effective single herbal drugs for cognitive disorders. They are Ginseng Radix, Acori Graminei Rhizoma, Cyperi Rhizoma, Coptidis Rhizoma, Pinelliae Rhizoma, Hoelen cum Pini Radix, and Rehmanniae Radix Preparata(Pinelliae Rhizoma, Hoelen cum Pini Radix, and Rehmanniae Radix Preparata were tied for $5^{th}$). And licensed herbal prescriptions derived from the planned search are Palbohoichoon-tang, Taehwa-hwan, Bosim-hwan, and so on. Among these, in consideration of the feasibility of research and possibility of success in development, Yukgunja-tang, Samhwangjichul-hwan can be selected as future study subjects. Through experimental studies and expert recommendations, we have derived herbal prescriptions that can be effective in treating cognitive disorders from licensed herbal medicines.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.572-586
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• 2021

With the advent of the 4th Industrial Revolution, the modern economy is transforming into a service-oriented economic society, and there is a growing need for companies to reorganize organizational culture, values, and human resources to suit the changing environment. Especially, even when times change, human capital is the most important factor in maintaining sustainable development and Corporate value, since all work is done by people. Therefore, in this study, in order to recognize the importance of human resources and verify the appropriate human resources for the changing service economy era, we reviewed the literature and that drew the human resources suitable for the recent service economy era Based on this, an empirical study was conducted on whether the suggested human resources factors were useful. To this end, a feasibility analysis, reliability analysis, correlation analysis, confirmatory factor analysis, and reference validity were conducted by dividing into a preliminary survey and a main survey. As a result, it was finally drawn with 30 items, 7 factors. The results of this study are expected to be used as basic data in various fields of research on human resources in the service economy era, and in-depth empirical studies are needed in the future.

• Journal of Wetlands Research
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• v.23 no.1
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• pp.85-93
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• 2021

Sewage separation which often involves installing a new pipe to separate wastewater flow from stormwater runoff flow can be costly and depends highly on its feasibility in a site. To be able to develop a potentially more economical alternative that can also lessen major road traffic disturbance during this process, a different approach where a smaller sewage separator pipe is installed inside an existing combined sewer pipe was investigated. A small-scale of a box sewer and the proposed sewage separator pipe was constructed in the laboratory to observe and compare the deposition of solids and other solid-associated major pollutants at different flow rates. In addition, three-dimensional flow simulations considering five different scenarios were conducted using Ansys Fluent to observe the effect of the proposed sewage separator pipe to the hydraulic flow if installed inside the combined sewer pipe. Results revealed that the deposition of TSS, TCOD, TN, and TP were reduced by at least 60% when the wastewater was conveyed by the sewage separator pipe instead of the combined sewer pipe. Moreover, the flow simulations conducted showed that there was little to no major disturbance in hydraulic flow and velocity distribution when the sewage separator was installed inside a straight pipe and even at pipe transitions such as intersections, turns, and drop in elevation. Considering the pipe dimensions and the results of the study, the proposed approach can be promising in terms of reduction in pollutant deposition without a major effect on the hydraulic flow. Further investigation and cost-analysis should be done in the future to support these preliminary findings and help alleviate the problems caused by combined sewer overflows by introducing an alternative approach.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.6
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• pp.1145-1156
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• 2022

In order to effectively secure site suitability for the development of large-scale offshore wind farms, it is essential to minimize the environmental impact of development and analyze the conflicts of benefit between social, ecological, and economic core values. In addition, a preliminary review of site adequacy must be preceded in order not to collide with other used areas in the marine spatial plan. In addition, it is necessary to conduct local meteorological characteristics analysis including wind resources near Jeollanam-do area before project feasibility study. Therefore, wind resource analysis was performed using the observation data of the meteorological mast installed in Wangdeungnyeo near Anmado, Yeonggwang, and the optimal site was selected after excluding geographical constraints related to the location of the offshore wind farm. In addition, the annual energy production was calculated by deriving the optimal wind farm arrangement results suitable for the local wind resources characteristics based on WindSim SW, and it is intended to be used as basic research data for site discovery and selection of suitable sites for future offshore wind farm projects.