• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.4
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• pp.375-382
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• 2020

As the 4th Industrial Revolution era in worldwide, interest in autonomous vehicles is increasing. but due to recent safety issues such as pedestrian accidents and car accidents, as a technical model for this, the demand for 3D HD maps (High Definition maps) is increasing in including lanes, road markings, road information, traffic lights and traffic signs etc. However, since some complementary points have been continuously raised according to demand, It is necessary to collect the opinions of institutions and companies utilizing HD maps and to improve HD maps. This study was conducted by utilizing the results of the contest for usability verification of HD Maps hosted by the National Geographic Information Institute and organized by the Spatial Information Industry Promotion Institute. For this study, we researched HD maps' layers and codes for HD maps object usability to improve HD maps, constructed HD maps object usability items accordingly, and contested usability verification of HD maps according to the items The contestants conducted verification and analyzed the results. As a result, the most frequently used code for each layer was the flat intersection, and the code showing the highest usage rate was a safety sign. In addition, the use rate of the sub-section and height obstacles was 16.67% and 8.88%, respectively, showing a low ratio. In order to utilize HD maps in the future, this study is expected to require research to continuously collect opinions from customers and improve data objects and data models that are actually needed by customers.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.1
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• pp.29-43
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• 2007

For effective management of water quality on the southern coast of korea, a three-dimensional eco-hydrodynamic model is used to predict water quality in summer and to estimate the reduction rate in pollutant loads that would be required to restore water quality. Under the current environmental conditions, in particular, pollutant loadings to the study area were very high, chemical oxygen demand (COD) exceeded seawater quality criteria to comply with current legislation, and water quality was in a eutrophic condition. Therefore, we estimated reduction rates of current pollutant loads by modeling. The model reproduced reasonably the flow field and water quality of the study area. If the terrestrial COD, inorganic nitrogen and phosphorus loads were reduced by 90%, the water quality criteria of Region A were still not satisfied. However, when the nutrient loads from polluted sediment and land were each reduced by 70% simultaneously, COD and $Chl-{\alpha}$ were restored. When we reduced the input COD and nutrient loads from the Nakdong River by 80%, $Chl-{\alpha}$ and COD of Region B decreased below $10\;{\mu}g\;1^{-1}$ and $2\;mg\;1^{-1}$, respectively. The water quality criteria of Region C were satisfied when we reduced the terrestrial COD and nutrient loads by 70%. Total allowable loadings of COD and inorganic nutrients in each region were determined by multiplying the reduction rates by current pollutant loads. Estimated high reduction rates, although difficult to achieve at the present time under the prevailing environmental conditions, suggest that water pollution is very severe in this study area, and pollutant loads must be reduced within total allowable loads by continuous and long-term management. To achieve the reduction in pollutant loads, sustainable countermeasures are necessary, including the expansion of sewage and wastewater facilities, polluted sediment control and limited land use.

• Journal of Korea Water Resources Association
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• v.52 no.10
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• pp.743-752
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• 2019

The flow in the meandering channel is characterized by the spiral motion of secondary currents that typically cause the erosion along the outer bank. Hydraulic structures, such as spur dike and groyne, are commonly installed on the channel bottom near the outer bank to mitigate the strength of secondary currents. This study is to investigate the effects of submerged vanes installed in a $90^{\circ}$ meandering channel on the development of secondary currents through three-dimensional numerical modeling using the hybrid RANS/LES method for turbulence and the volume of fluid method, based on OpenFOAM open source toolbox, for capturing the free surface at the Froude number of 0.43. We employ the second-order-accurate finite volume methods in the space and time for the numerical modeling and compare numerical results with experimental measurements for evaluating the numerical predictions. Numerical results show that the present simulations well reproduce the experimental measurements, in terms of the time-averaged streamwise velocity and secondary velocity vector fields in the bend with submerged vanes. The computed flow fields reveal that the streamwise velocity near the bed along the outer bank at the end section of bend dramatically decrease by one third of mean velocity after the installation of vanes, which support that submerged vanes mitigate the strength of primary secondary flow and are helpful for the channel stability along the outer bank. The flow between the top of vanes and the free surface accelerates and the maximum velocity of free surface flow near the flow impingement along the outer bank increases about 20% due to the installation of submerged vanes. Numerical solutions show the formations of the horseshoe vortices at the front of vanes and the lee wakes behind the vanes, which are responsible for strong local scour around vanes. Additional study on the shapes and arrangement of vanes is required for mitigate the local scour.

• Maritime Security
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• v.4 no.1
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• pp.57-82
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• 2022

The objective of this treatise is to explore the limitations of the current navy manpower utilization system and the ways to improve it from the perspective of Generation Z. As Generation Z, following Millennials, has finally come of age, this new group is constituting a gradually greater proportion of military personnel. Due to the typical characteristics of naval operations, the harmony between Millennials and Generation Z, which is differentiated from Generation X in view of dispositions and traits, is one of the essential issues to be discussed. Generally, in a naval vessel, there are numerous pieces of equipment necessary to carry out a wide range of missions and a large number of crew members who operate them with consistent levels of fighting power. This is all while members are living together within the narrow space throughout the 24 hours of each day. Under such particular circumstances, any inter-generational conflicts may have a disruptive effect on the successful accomplishment of naval missions. Currently, new generations of military personnel are facing social difficulties in different aspects compared with the previous generations, and also have different viewpoints on the military. In this regard, in order to foster true harmony between generations, it is considered necessary to take a closer look at the inter-generational differences from their respective standpoints and to examine whether the military organization has taken adequate steps to respond to such changes. Accordingly, Chapters 1 and 2 cover the environments in which Millennials and Generation Z were raised during their childhood to young adulthood, which are distinct from those of older generations, their viewpoints formed based on such backgrounds, and the need to resolve various conflicts between generations. In Chapter 3, the current actions taken by overseas military powers to enhance the coexistence with Generation MZ are analyzed to find the significant implications they had. Chapter 4 examines the operation environments specific to the navy; identifies the potential barriers to achieving harmony between generations by assessing the current status of personnel utilization in the Korean navy in terms of the seaman, petty officer, and the officer, as well as policy; and outlines the solutions to drive harmony. Finally, Chapter 5 emphasizes the need to establish a genuine empathy between generations based on the understanding of unique inter-generational characteristics. This section also discusses the importance of addressing difficulties in utilizing technology-centered naval manpower, and forecasts a scenario of a naval organization that resolves the problem of utilizing naval personnel and the inter-generational conflicts in the future.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.2
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• pp.80-98
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• 2023

This study explores the effectiveness of various data preprocessing algorithms for improving subseasonal to seasonal (S2S) climate predictions from six climate forecast models and their Multi-Model Ensemble (MME) using a deep learning-based postprocessing model. A pipeline of data transformation algorithms was constructed to convert raw S2S prediction data into the training data processed with several statistical distribution. A dimensionality reduction algorithm for selecting features through rankings of correlation coefficients between the observed and the input data. The training model in the study was designed with TimeDistributed wrapper applied to all convolutional layers of U-Net: The TimeDistributed wrapper allows a U-Net convolutional layer to be directly applied to 5-dimensional time series data while maintaining the time axis of data, but every input should be at least 3D in U-Net. We found that Robust and Standard transformation algorithms are most suitable for improving S2S predictions. The dimensionality reduction based on feature selections did not significantly improve predictions of daily precipitation for six climate models and even worsened predictions of daily maximum and minimum temperatures. While deep learning-based postprocessing was also improved MME S2S precipitation predictions, it did not have a significant effect on temperature predictions, particularly for the lead time of weeks 1 and 2. Further research is needed to develop an optimal deep learning model for improving S2S temperature predictions by testing various models and parameters.

• Journal of Public Diplomacy
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• v.3 no.1
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• pp.1-19
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• 2023

Objectives: This study aims to discover how the spread of K-POP and the diversification of the Korean Wave affects Korea's national reputation. K-POP stars are diversifying their interactions with fandom by creating an online space to consume various products and services related to their stars and engage in fan activities. Because of this, this study aims to examine the relevance of K-POP to national reputation through a parasocial relationship with K-POP stars by fandom forming a community and utilizing media. Methods: An online survey was conducted in English using the Amazon survey company Mechanical Turk for BTS fans living in the United States. A total of 195 people's data, excluding incomplete responses, were used for the analysis. Results: It was found that BTS fans' social media participation activities themselves did not directly affect Korea's national reputation. But the mediating effect of BTS fans' parasocial relationship was found. That is, BTS fans' social media participation activities had a positive effect on their parasocial relationships with BTS which in turn had a positive effect on their national reputation. Conlusions: The use and participation of BTS fans in social media in Korea's national reputation has no significant effect on itself, but it has been found that it affects the national reputation through forming parasocial relationships. From the study results, the parasocial relationship of K-POP fans can be used as a strategic mechanism to enhance the national image and Korea's national reputation.

• Journal of Korea Water Resources Association
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• v.48 no.7
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• pp.553-566
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• 2015

Acoustic Doppler Current Profilers(ADCPs) have capability to concurrently capitalize three-dimensional velocity vector and bathymetry with highly efficient and rapid manner, and thereby enabling ADCPs to document the hydrodynamic and morphologic data in very high spatial and temporal resolution better than other contemporary instruments. However, ADCPs are also limited in terms of the inevitable unmeasured regions near bottom, surface, and edges of a given cross-section. The velocity in those unmeasured regions are usually extrapolated or assumed for calculating flow discharge, which definitely affects the accuracy in the discharge assessment. This study aimed at scrutinizing a conventional extrapolation method(i.e., the 1/6 power law) for estimating the unmeasured regions to figure out the accuracy in ADCP discharge measurements. For the comparative analysis, we collected spatially dense velocity data using ADV as well as stationary ADCP in a real-scale straight river channel, and applied the 1/6 power law for testing its applicability in conjunction with the logarithmic law which is another representative velocity law. As results, the logarithmic law fitted better with actual velocity measurement than the 1/6 power law. In particular, the 1/6 power law showed a tendency to underestimate the velocity in the near surface region and overestimate in the near bottom region. This finding indicated that the 1/6 power law could be unsatisfactory to follow actual flow regime, thus that resulted discharge estimates in both unmeasured top and bottom region can give rise to discharge bias. Therefore, the logarithmic law should be considered as an alternative especially for the stationary ADCP discharge measurement. In addition, it was found that ADCP should be operated in at least more than 0.6 m of water depth in the left and right edges for better estimate edge discharges. In the future, similar comparative analysis might be required for the moving boat ADCP discharge measurement method, which has been more widely used in the field.

• The Korean Journal of Air & Space Law and Policy
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• v.30 no.1
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• pp.207-244
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• 2015

Aviation safety is the stage in which the risk of harm to persons or of property damage is reduced to, and maintained at or below, an acceptable level through a continuing process of hazard identification and risk management. Many accidents and incidents have been taking place since 2014, while there had been relatively safer skies before 2014. International civil aviation community has been exerting great efforts to deal with these emerging issues, thus enhancing and ensuring safety throughout the world over the years. The Preamble of the Chicago Convention emphasizes safety and order of international air transport, and so many Articles in the Convention are related to the safety. Furthermore, most of the Annexes to the Convention are International Standards and Recommended Practices pertaining to the safety. In particular, Annex 19, which was promulgated in Nov. 2013, dealing with safety management system. ICAO, as law-making body, has Air Navigation Commission, Council, Assembly to deliberate and make decisions regarding safety issues. It is also implementing USOAP and USAP to supervise safety functions of member States. After MH 370 disappeared in 2014, ICAO is developing Global Tracking System whereby there should be no loophole in tracking the location of aircraft anywhere in world with the information provided by many stakeholders concerned. MH 17 accident drove ICAO to install web-based repository where information relating to the operation in conflict zones is provided and shared. In addition, ICAO has been initiating various solutions to emerging issues such as ebola outbreak and operation under extreme meteorological conditions. Considering the necessity of protection and sharing of safety data and information to enhance safety level, ICAO is now suggesting enhanced provisions to do so, and getting feedback from member States. It has been observed that ICAO has been approaching issues towards problem-solving from four different dimensions. First regarding time, it analyses past experiences and best practices, and make solutions in short, mid and long terms. Second, from space perspective, ICAO covers States, region and the world as a whole. Third, regarding stakeholders it consults with and hear from as many entities as it could, including airlines, airports, community, consumers, manufacturers, air traffic control centers, air navigation service providers, industry and insurers. Last not but least, in terms of regulatory changes, it identifies best practices, guidance materials and provisions which could become standards and recommended practices.

• Trans-
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• v.8
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• pp.95-127
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• 2020

This research is based on using Bartenieff Fundamentals to analyze the fundamentals of Tai Chi Chuan's movements in order to develop the methods of relaxation from Tai Chi Chuan's principle movement movements It also shows that the two techniques have commonalities in many ways. First of all, taking a philosophical approach on the body movements of Tai Chi Chuan and Bartenieff, for both methods the ultimate goal is the integration of mind and body. In other words, there is a thread of connection between the East's body and mind monism and the west's Body Awareness. Secondly, looking at it from a Breath Support standpoint as used in the Bartenieff method, the two methods both use the breathing to naturally move the body and relax the body. In Tai Chi Chuan the Breath is the basis of life and the strength of the Body. So the breathing of Tai Chi chuan is what makes body and mind communicate, harmonize and integrate. In other words, Breathing in Tai Chi is realized through mental fusion and affects the movements. This is the same as the Breath Support of Bartenieff. It is said that in every aspect the Breath Support of Bartenieff influences the movement and changes both the inner and outer form of the body. Thirdly, looking at the Core Support used in the Bartenieff method, both methods emphasize core. At the same time of moving and being conscious of one's core, the usage of muscles can be deeper rather than superficial and this enables strong and flexible movement. In Tai Chi Chuan abdominal muscles used when one coughs are consciously engaged through abdominal breathing and so strength is collected in the core. When one exercises like that the core becomes more stable and breathing becomes more smooth. Fourthly, analyzing the Rotary Factor used in the Bartenieff Fundamentals, they both use rotary movement to reach the goal of physical relaxation. The rotation factor of Bartenieff allows movement to be easier and more free because of the characteristic of joint exercise where the center axis moved in three dimensions, this is the same in Tai Chi chuan. According to Tai Chi chuan's circle and Spiral Movements, it can achieve the relaxation through switching into a seamless flow and access space as much as possible. Finally, when looking at Developmental Patterning through Bonnie Bainbridge Cohen's Body-Mind Centering Work theory, presented from Bartenieff developmental model are similar with the developmental process of Tai Chi chuan Breath, Core-Distal Connectivity/Navel Radiation, Head-Tail Connectivity/Spinal Movement, Upper-Lower Connectivity/Homologous, Body-Half Connectivity/Homo-Lateral Connectivity, Cross-Lateral Connectivity/Contra-Lateral Connectivity. They are all similar. In other words, in Tai Chi Chuan energy is gathered in the core through breathing, upper and lower body are connected through the spine, not only homo-laterally but also cross-laterally. Through this study the expression of the dance movements can be more natural. Additionally based on the Body Awareness balance usage of the central axis, joints and body can develop the relax technique.

• Korean Journal of Heritage: History & Science
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• v.51 no.2
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• pp.22-37
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• 2018

Unmanned aerial vehicles (UAV) have attracted considerable attention both at home and abroad. The UAV is equipped with a camera that shoots images, which is advantageous for access to areas where archaeological investigations are not possible. Moreover, it is possible to acquire three-dimensional spatial image information by modeling the terrain through aerial photographing, and it is possible to specify the interpretation of the terrain of the survey area. In addition, if we understand the change of the terrain through comparison with past aerial photographs, it will be very helpful to grasp the existence of the ruins. The terrain modeling for searching these remains can be divided into two parts. First, we acquire the aerial photographs of the current terrain using the drone. Then, using image registration and post-processing, we complete the image-joining and terrain-modeling using past aerial photographs. The completed modeled terrain can be used to derive several analytical results. In the present terrain modeling, terrain analysis such as DSM, DTM, and altitude analysis can be performed to roughly grasp the characteristics of the change in the form, quality, and micro-topography. Past terrain modeling of aerial photographs allows us to understand the shape of landforms and micro-topography in wetlands. When verified with actual findings and overlapping data on the modelling of each terrain, it is believed that changes in hill shapes and buried Microform can be identified as helpful when used in low-flying applications. Thus, modeling data using aerial photographs is useful for identifying the reasons for the inability to carry out archaeological surveys, the existence of terrain and ruins in a wide area, and to discuss the preservation process of the ruins. Furthermore, it is possible to provide various themes, such as cadastral maps and land use maps, through comparison of past and present topographical data. However, it is certain that it will function as a new investigation methodology for the exploration of ruins in order to discover archaeological cultural properties.