• Journal of the korean society of oceanography
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• v.32 no.4
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• pp.181-190
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• 1997

A large subtidal sand ridge (Jungang Satoe) in Asan Bay, on the west coast of Korea, was studied in order to understand the morphology and sediment transport trend in a macrotidal setting, by means of analyzing sediment samples, current data, side-scan sonographs and seismic profiles. The ridge is about 15 km long and 2-5 km wide, with a relief of about 15 m. It is elongated in the flow direction of flood (SE) and ebb (NW) tidal currents, but asymmetrical in cross section. The western and southwestern side of the ridge is characterized by relatively gentle slopes averaging 0.4$^{\circ}$, whereas on the northeastern side, relatively steep slopes were mapped with 1.6$^{\circ}$ slope angles. Tidal currents associated with the ridge are very strong; maximum surface velo-cities range from neap values of 50 cm/s to spring values of 130 cm/s. The shear velocities during flood and ebb are strong enough to erode and transport sands on the ridge. Sand waves and megaripples (dunes) are the most common bedforms produced by the tidal currents, which show regional differences in shape and size on the ridge. The distribution pattern of these bedforms in-dicates that the flood tidal currents are dominant on the offshore (northwest) side of the ridge, whereas the onsho.e (southeast) side of the ridge is ebb-dominated. The sand transport path as inferred from bedform orientations is directed toward the ridge crest on the flanks, whereas on the crest, it is near-longitudinal to the ridge axis. The convergent, upslope movement of sands on the ridge flanks appears to be important in sand ridge building and maintenance. A significant ridge migration toward the northeast can be suspected on the basis of the ridge morphology, which may cause offshore hazards for navigation.

• Journal of the Korean GEO-environmental Society
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• v.14 no.4
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• pp.5-13
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• 2013

The water leakage of reservoir embankment usually occurs around channelling pipes, which gives little influence on the embankment in a normal state. However, the embankment can be destroyed when the water level of reservoir increases with heavy rain and the rainy season in summer. Investigating the water vein and its path is therefore very important from the viewpoint of disaster prevention and embankment maintenance. The water leakage in dams and levees where the channelling pipes are working as weak zone was analyzed by using both numerical simulation and experimental method in this study. To detect the water leakage, an electrical resistivity survey was used and investigated for its' usability. The numerical results show the size and location of weak zone increases the importance of selection of electrode spacing. The leakage experiments of model embankment present the best result is obtained under the conditions of electrode spacing of 0.3m and dipole-dipole array. By studying the water leakage in dams and levees, the electrical resistivity survey is observed it is a very useful method to predict the leakage.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.6
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• pp.530-538
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• 2020

Safety inspections of outdoor advertisements are conducted to determine the aging status, specifications, and compliance with design documents. Regular inspections are conducted on outdoor advertisements from a safety perspective, as they not only undermine the aesthetic elements of the city but also could cause falls on roads or pedestrian paths. However, the current safety inspection methods are at risk of various accidents during the inspection advertisements on the outer wall of the building. And it is difficult to conduct in-depth inspections on them if they are fixed to the elevation of the building. Furthermore, there also is a risk of safety accidents, such as advertising structures falling onto a pedestrian path. Therefore, this paper aims to enhance the safety inspection system of outdoor advertisements using drones. This paper also intends to propose measures for facility inspection history management such as safety inspection cycle, maintenance, and removal of signboards.

• Journal of Aerospace System Engineering
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• v.17 no.1
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• pp.68-78
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• 2023

In this paper, improvement measures were studied for false alarm (abnormal lighting) of emergency hydraulic warning light due to RF radiation signals in aircraft. When the warning lamp of the emergency hydraulic system is lit during flight due to electromagnetic interference caused by RF radiation signals, it affects flight mission and safety which can result in efficiency degradation and maintenance of flight mission. For false alarm of emergency hydraulic warning light, root cause analysis and troubleshooting were carried out. By shielding a composite strip under fuselage of the aircraft located in the path of the RF radiation signal, the RF radiation signal flowing into the emergency hydraulic indicator was blocked. Results of applying the improvement method through ground and flight monitoring were also described.

• Journal of People, Plants, and Environment
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• v.22 no.6
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• pp.629-639
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• 2019

This study was conducted to analyze the characteristics of visitors to Hadong Bukcheon Iceland Poppy (BIP) Festival in order to sustain and enhance local flower festivals as a garden tourism. A questionnaire was distributed to BIP Festival visitors from May 18 to 27, 2018. A total of 167 responses were subject to be analyzed. Descriptive statistics analysis was mainly used and focused on describing the results in direct to explain the BIP Festival as a garden tourism. The number of female visitors and those in their 40s and 50s was high. Most of the visitors were found to live in other cities or counties near the area where BIP Festival was held and to prefer festivals held on the theme of nature and local features. The revisit rate and awareness of BIP Festival were 52.1% and 72.5% respectively. They mainly obtained the information on BIP Festival from people around them including family members, friends and colleagues, or from the Internet. Most answered that BIP festival was the most important destination on their trip. The major motives of BIP Festival visit included "spending quality time with family or friends (34.1%)", "appreciating Iceland poppy and gardens (25.6%)", and "enjoying oneself (tranquility, mental rest, etc.; 21.3%). As a companion, family and friends/colleagues accounted for 62.3% and 26.3% respectively. Most were found to spend 1-2 hours on visiting BIP festival and stay in Hadong county for a quarter of a day. In satisfaction of BIP Festival itself, "display and maintenance of Iceland poppy (3.76)" and "easiness of viewing (places arrangement, path, etc.) (3.57)" were high. In satisfaction of public relation and information, "service and hospitality of guides and desk clerks (3.66)" was high. The intention to revisit BIP Festival was nearly affirmative (3.73-3.80).

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.3
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• pp.62-72
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• 2023

Recently, the importance of monitoring and management measures for bicycle road related facilities has been increasing. However, research on the monitoring and evaluation of users' safety and convenience in walking spaces including bicycle path is insufficient. In this study, we would like to construct health monitoring data for cylists-pedestrians mixed road using a mobile mapping system, and propose a plan to calculate the level of service of the mixed roads from the perspective of pedestrians and cyclists using artificial intelligence based object detection techniques. The monitoring and level of service calculation method of cylists-pedestrians mixed roads proposed in this study is expected to be used as basic information for planning and management such as maintenance and reconstruction of walking spaces in preparation for the increase of electric bicycles and personal mobility in the future.

• Composites Research
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• v.36 no.2
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• pp.108-116
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• 2023

In this paper, kinematic design and multi-body dynamics analysis were conducted to develop a small manipulator platform for automating the maintenance of structures made of composite materials. To design manipulator kinematically, the existing composite repair process was considered. The 3D design was conducted after selecting the basic specifications of manipulator and end-effecter in consideration of the patch lamination process for repair. Then, variables necessary for simulation and control were generated in MATLAB through inverse kinematic analysis. To evaluate the structural stability of platform, multibody dynamics analysis was conducted using Altair Inspire and Optistruct. Based on the simulation conducted in Inspire, multibody dynamics analysis was conducted in Optistruct, and structural stability was verified through the results of maximum displacement and Von-Mises stress over time. To verify the design, manufacturing and controlling of platform were conducted and compared with the simulation. It was confirmed that the actual repair process path and the simulation showed a good agreement.

• Journal of Fashion Business
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• v.27 no.3
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• pp.50-62
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• 2023

The e-commerce fashion market has experienced a remarkable growth, leading to an overwhelming availability of shared information and numerous choices for users. In light of this, chatbots have emerged as a promising technological solution to enhance personalized services in this context. This study aimed to develop user-product attributes for a chatbot-based personalized fashion recommendation service using big data text mining techniques. To accomplish this, over one million consumer reviews from Coupang, an e-commerce platform, were collected and analyzed using frequency analyses to identify the upper-level attributes of users and products. Attribute terms were then assigned to each user-product attribute, including user body shape (body proportion, BMI), user needs (functional, expressive, aesthetic), user TPO (time, place, occasion), product design elements (fit, color, material, detail), product size (label, measurement), and product care (laundry, maintenance). The classification of user-product attributes was found to be applicable to the knowledge graph of the Conversational Path Reasoning model. A testing environment was established to evaluate the usefulness of attributes based on real e-commerce users and purchased product information. This study is significant in proposing a new research methodology in the field of Fashion Informatics for constructing the knowledge base of a chatbot based on text mining analysis. The proposed research methodology is expected to enhance fashion technology and improve personalized fashion recommendation service and user experience with a chatbot in the e-commerce market.

• Information Systems Review
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• v.22 no.4
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• pp.41-58
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• 2020

This study addresses the issue of which factors make domestic works have turnover intention. To pursue this research issue, we utilized a public database "2017 Occupational Migration Path Survey", administerd by Korea Employment Information Service (KEIS). Decision tree method was applied to extract crucial factors influencing workers' turnover intention. They include 'the degree of matching the level of education with the level of work', 'the possibility of individual development', 'the job-related education and training', 'the promotion system', 'wage and income', 'social reputation for work' and 'the stability of employment'.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.4
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• pp.81-91
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• 2017

The purpose of this study is to establish a system of planning elements necessary for effective healing garden. We suggested new planning parts and elements for healing garden through analyzing prior literature and evaluated the importance of planning elements through expert surveys. The results of the study are stated as follows. First, we suggested five planning parts and 19 planning elements. $\LARGE{\cdot}$ Planning parts: Physical environment, social environment, cognitive environment, functional environment, psychological environment. $\LARGE{\cdot}$ Planning elements: Plant planting, garden view, hydroponic space, shade space, work space, recreation space, community space, exercise space, landmark element, sign system, safe facilities and materials, disaster safety facility, universal design, accessible path, economical maintenance, sight openness, privacy guaranteed, variety of resting space, artistic element. Second, as a result of analyzing the importance of planning elements, the first place was the planting, the second place was the safety facilities for the disaster, and the third was diversity of rest space. In addition, the artistic elements and the landmark elements were ranked 18th and 19th, respectively. Third, we evaluated the level of importance of planning elements and classified it into three groups. The most important A group included two elements(plant planting, disaster safety facility), the next important B group included eleven elements(variety of resting space, community space, hydroponic space, universal design, safe facilities and materials, economical maintenance, accessible path, privacy guaranteed, garden view, work space, sight openness) and the less important C group included six elements(shade space, exercise space, recreation space, sign system, artistic element, landmark element). We suggest that, in creating a healing garden, the two elements in A group are essential elements and the eleven elements in B group should be importantly applied. In addition, the six elements in C group are recognized as arbitrarily selectable elements due to the relatively low importance levels.