• 한국초전도ㆍ저온공학회논문지
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• 제18권2호
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• pp.1-4
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• 2016

To observe the superconducting current and structural properties of high critical temperature ($T_c$) superconductors (HTS), we suggest the following imaging methods: Room temperature imaging (RTI) through thermal heating, low-temperature bolometric microscopy (LTBM) and Raman scattering imaging. RTI and LTBM images visualize thermal-electric voltages as different thermal gradients at room temperature (RT) and superconducting current dissipation at near-$T_c$, respectively. Using RTI, we can obtain structural information about the surface uniformity and positions of impurities. LTBM images show the flux flow in two dimensions as a function of the local critical currents. Raman imaging is transformed from Raman survey spectra in particular areas, and the Raman vibration modes can be combined. Raman imaging can quantify the vibration modes of the areas. Therefore, we demonstrate the spatial transport properties of superconducting materials by combining the results. In addition, this enables visualization of the effect of current flow on the distribution of impurities in a uniform superconducting crystalline material. These imaging methods facilitate direct examination of the local properties of superconducting materials and wires.

• 산경연구논집
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• 제13권3호
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• pp.13-24
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• 2022

Purpose: The purpose of this paper is to investigate key factors that affect customer dissatisfaction on public transportation system by highlighting the necessity of citizen participation and improved management of advanced technology for sustainability. Research questions applied in this study include following; i) how are factors on dissatisfaction related to types of transportation modes; ii) how do perceived proposed factors affect citizen dissatisfaction; iii) how do the improvement of public transportation service affect the level of expected satisfaction; and iv) how do expected satisfaction affect policy agreement and government trust. Research design, data and methodology: For qualitative research, civil opinions were collected and chi-square analysis was applied using keywords. For quantitative research, online survey was collected and factor and multiple regression analyses were applied. 3) Results: This study found that efficiency of operation system and safety on dissatisfaction showed significant in all three public transportation modes. This study found that perception of government policy and trust on government will increase as expected satisfaction increases. Conclusions: This study provides managerial and policy implications on society and policy makers by addressing necessity of improving strategies for public transportation system with the consideration of citizen relationship management and sustainable development.

• 한국콘텐츠학회논문지
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• 제9권11호
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• pp.140-150
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• 2009

본 연구는 개인의 지적능력 개발을 위한 기초연구로서 개인의 특성 차이를 대뇌모형으로 정의하였으며, 개인의 특성에 따라 선호하는 온라인 게임의 요소가 어떤 차이가 있는지 설문을 통하여 확인하고 활용가능성을 살펴보았다. 뇌 성향은 곧 개인의 지적능력을 관장하며 인격, 기호, 성격, 의사결정 및 행동의 패턴 등을 정의한 것이라 말할 수 있으며 창의성과 밀접한 관련이 있다. 이러한 뇌 성향에 근간을 둔 대뇌반구모델(Cerebral Hemispheric Model-CHM)을 바탕으로 2가지 Model로 개인의 성향을 구분하였다. 설문을 통하여 대뇌반구모형별 게임요소의 요소상관표를 작성, 대뇌반구모형별 게임요소의 차이를 확인 할 수 있었다. 또한 정의된 대뇌반구의 개인성향별 게임 선호요소를 바탕으로 각 개인의 뇌 성향을 확인하고 확인된 뇌 성향 이외의 다른 뇌 성향을 개발하기 위한 컨셉(Concept) 가이드라인을 제시하고, 이를 통하여 개인의 뇌 사고성향 개발을 바탕으로 하는 교육용 게임에서부터 다양한 장르의 컨텐츠를 사용자의 성향에 최적화하여 즐거움을 느끼며 자기개발을 할 수 있는 기초 연구 자료가 될 수 있으며, 개인의 사고성향 개발을 통하여 지적 능력을 향상시킬 수 있을 것이다.

• Smart Structures and Systems
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• 제15권3호
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• pp.665-682
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• 2015

Structural identification or St-Id is 'the parametric correlation of structural response characteristics predicted by a mathematical model with analogous characteristics derived from experimental measurements'. This paper describes a St-Id exercise on Humber Bridge that adopted a novel two-stage approach to first calibrate and then validate a mathematical model. This model was then used to predict effects of wind and temperature loads on global static deformation that would be practically impossible to observe. The first stage of the process was an ambient vibration survey in 2008 that used operational modal analysis to estimate a set of modes classified as vertical, torsional or lateral. In the more recent second stage a finite element model (FEM) was developed with an appropriate level of refinement to provide a corresponding set of modal properties. A series of manual adjustments to modal parameters such as cable tension and bearing stiffness resulted in a FEM that produced excellent correspondence for vertical and torsional modes, along with correspondence for the lower frequency lateral modes. In the third stage traffic, wind and temperature data along with deformation measurements from a sparse structural health monitoring system installed in 2011 were compared with equivalent predictions from the partially validated FEM. The match of static response between FEM and SHM data proved good enough for the FEM to be used to predict the un-measurable global deformed shape of the bridge due to vehicle and temperature effects but the FEM had limited capability to reproduce static effects of wind. In addition the FEM was used to show internal forces due to a heavy vehicle to to estimate the worst-case bearing movements under extreme combinations of wind, traffic and temperature loads. The paper shows that in this case, but with limitations, such a two-stage FEM calibration/validation process can be an effective tool for performance prognosis.

• 한국유기농업학회지
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• 제10권3호
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• pp.25-39
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• 2002

This paper aims to provide quite recent information on the organic industry in the U.S. Major focuses are on the development of cultivation and marketing of fresh and processed organic produce and foods, newly enforced certification program, consumers' purchasing behaviors toward organic foods, and social survey results administered to the organic farmers in the U.S. The U.S. recorded 8 billion dollars' sale of organic foods in 2000, which was the largest in the world and showed 23% growth compared to the previous year. Yet the organic industry is still a niche market, occupying merely 1.5% of total food sale amount. The natural foods markets have not been so concentrated in the U.S., but it is changing and a few wholesale mart such as Whole Foods is emerging. Recent introduction of new certification program provide unified and sole standard at the federal level to which every certifier needs to adjust itself in order to be acceredited by the government. According to a social survey, consumers purchase organic foods because they concern about health, they stick to their own modes of life favoring natural foods, and so on. Another social survey shows that most organic farmers sell their produces to wholesalers, distributers, or producer coop, and direct sale to visitors at their own farm comprises of about 8 percent of their organic land.

• 한국안전학회지
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• 제38권1호
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• pp.9-17
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• 2023

In this study, we aimed to identify the important hazard factors and determine their criticality in causing serious accidents in vehicle-mounted mobile elevated work platforms (MEWPs). Fuzzy failure modes and effects analysis (FMEA)was performed using accident data and a survey of experts. To determine the hazard factors, the accident data for the last 10 years were used and a questionnaire survey was designed. The questionnaire survey was sent to four experts in the field of occupational safety to determine the severity, occurrence, and detectability of serious accidents in MEWPs. Furthermore, objective RPN scores and risk priority were obtained using fuzzy FMEA. Finally, the criticality of hazard factors in descending order was found to be overloading, non-installation or defective installation of outriggers, breakage due to wire rope aging, and illegal remodeling of vehicle structures. The results were verified by comparing the occurrence data of serious disasters.

• 천문학회보
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• 제44권2호
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• pp.68.2-68.2
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• 2019

Most of the stellar mass accretes during the early evolutionary stage of protostars. However, the accretion process in protostars is in a veil of the thick envelope. Monitoring the submillimeter emission from the envelope is a way to trace the accretion process in protostars since the submillimeter emission linearly responses to the temperature of the envelope, which is heated by the accretion process at the center. In the JCMT transient Survey, we detected a submillimeter variable, EC 53. EC 53 is a Class 1 protostar that was known to have a periodic variation at NIR. EC 53 has been monitored with United Kingdom InfraRed Telescope (UKIRT), Liverpool telescope, and JCMT/SCUBA-2 since we detected the 850 ㎛ flux enhancement in the JCMT transient survey. We also adopt the photometric data sets of Wide-field Infrared Survey Explorer (WISE). Over all wavelengths from NIR to submillimeter, we see two modes of variation, a 1.5-years periodic variation and a long-term increase. We present the light curves of EC 53 at multi-wavelengths and discuss the cause of variability in EC 53.

• 사상체질의학회지
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• 제29권3호
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• pp.224-231
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• 2017

Objectives Several researches have been done to develop instruments or questionnaire for diagnosis of sasang constitution. In this study, we developed a user-friendly web system to enhance the utilization of KS-15. Methods The KS-15 Web application was constructed by considering the responsive web design and easy survey answer. This system is designed only to authorized users for security purposes, and provides two modes, simple mode and expert mode, depending on the purpose of using the system. A simple mode do not keep user information and survey answer in the database. An expert mode support management of patients, diagnosis of sasang constitution and statistical functions. Results & Conclusions The developed KS-15 system can be operated from any smart device's web browser. In order to use information in clinic field, it was developed so that it can be accessed only by authorized users. It can be divided into an account which can use only simple mode and an account which can use expert mode by using a difference in access authority. These functions can enhance the applicability of sasang constitution in real life such as clinical or education.

• 대한교통학회지
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• 제18권1호
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• pp.27-34
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• 2000

이 연구는 최근 소비자 행동분석에서 많이 사용되고 있는 설문조사에 의한 Stated Preference의 방법론을 채택하여 항공여객수요의 가격탄력성을 분석하였다. 우리나라의 국내선 항공은 항공요금이 지금가지 인가제나 신고제로 규제되어 왔기 때문에 통상의 총량자료에 의한 회귀분석으로는 가격탄력성 도출이 어려우며 특별한 분석방법론을 필요로 한다. 이 연구에서는 항공여객에 대한 설문조사로 항공편과 철도, 버스, 승용차 등 대체교통수단과의 선택 여부에 대한 자료를 입수한 후, SP기법에 따른 Logit model로 분석하여 항공수요의 가격탄력성과 대체교통수단으로의 모드별 쉐어 변환율을 Sample Enumeration 방식에 의해 추정하였다 대체 가격탄력성은 -0.6∼-0.9의 값으로 밝혀졌으며 대체교통수단으로는 주로 철도를 선택하고 일부 버스를 선택하며 승용차는 거의 선택하지 않는 것으로 조사되었다.

• 유통과학연구
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• 제19권10호
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• pp.17-22
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• 2021

Purpose: Covid-19 has caused an unprecedented situation for the tourism industry with slumping demand during the outbreak and many uncertainties about tourist behavior in the post-pandemic. This study is aimed to discover the distribution in the behavior of tourists in Vietnam, whose government has taken serious and early actions towards the health crisis and among the earliest to reopen the economy. Research design, data, and methodology: We adopted a mixed-method approach - combining qualitative interviews with quantitative research using a questionnaire survey. Through the form of the online survey through social networking channels: Facebook, Gmail. The study received 261 valid responses for analysis. Multivariate analysis techniques were used: descriptive statistics, exploratory factor analysis (EFA). Results: From the data and result of EFA, the result showed that the distribution of tourist behavior could be grouped into four main factors, including (1) the general impacts, (2) travel-related behaviors; (3) attitudes and preferences regarding modes of tours and destinations; (4) awareness of safety and hygiene. Conclusions: These results highlighted the importance of the theory of perceived risks in explaining the travelers' prudent decisions. In addition, this study provides practical implications for policymakers and various stakeholders of Vietnam's tourism industry in formulating the recovery strategy.