• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.163-168
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• 2020

Since the industrialization in the 1960s, Korea has been expanding its transportation infrastructure, such as building bridges. Owing to bridge construction, studies on stability review have been carried out, and stability-securing technology has been developed. On the other hand, these were applied mainly to the upper part of the bridge, so applications to the lower part are limited. In particular, scour at the bridge pier causes erosion in the riverbed and bridge collapse. Hence, prevention studies and countermeasures are needed. In this study, an empirical formula was developed to evaluate the scour depth of a bridge, which was calculated through multiple linear regression analysis using the hydraulic model study data conducted in previous studies. The formula, which had a value of 0.91, was applied to the model test data that was not used for development to verify the developed formula. When the pier scour depths were compared in 23 cases, the error rate was less than 20% in 16 cases (70%). The empirical formula developed in this study is applicable to pier scour-depth calculations. Further research will be needed to develop a more accurate empirical formula for pier scour-depth calculations, and it is expected to reduce bridge damage caused by scour.

• Land and Housing Review
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• v.13 no.4
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• pp.1-12
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• 2022

Clean water is an essential urban infrastructure in human daily life, and water plays a vital role in public health. Due to restrictions on outdoor activities during COVID-19, time staying at home has increased. Therefore, it is plausible to assume that large-scale disaster incidences such as COVID-19 will affect water consumption. In this regard, this research aims to explore the factors that influence household water use during COVID-19. The analysis period of the study is 2020, and the geographical scope covers Seoul and Incheon. A dependent variable was water consumption in the autonomous districts of Seoul and Incheon, and the factors reflecting urban characteristics were used as independent variables. Multiple regression was used for analysis, and the unit of analysis was the autonomous district in Seoul and Incheon. The finding confirmed that the pandemic situation caused an increase in water consumption. In addition, it supports policy for the elderly so that they can use water without financial difficulty. It implies that a stable supply of clean water is essential for managing infectious diseases. The findings of this study are expected to provide some implications for efficient water supply policies and efficient water supply management in the event of the spread of infectious diseases such as COVID-19.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.469-476
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• 2021

An electronic attack (EA) system is an essential weapon system for performing electronic warfare missions that contain signal tracking and jamming against multiple threats using electromagnetic waves, such as air defense radars, wireless command and communication networks, and guided missiles. The combat effectiveness can be maximized, and the survivability of militarily protecting combat power can be enhanced through EA mission operations, such as disabling the functions of multiple threats. The EA system can be used as a radio frequency jamming system to respond to drone attacks on the core infrastructure, such as airports, power plants, and communication broadcasting systems, in the civilian field. This study examined the criteria for classification according to the electronic attack missions of foreign EA systems based on an aviation platform. The foreign R&D trends by those criteria were investigated. Moreover, by analyzing the R&D trends of domestic EA systems and future battlefields in the domestic security environments, this paper proposes technological development plans of EA systems suitable for the future battlefield environments compared to the foreign R&D trends.

• Journal of the Korean Geotechnical Society
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• v.37 no.6
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• pp.29-37
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• 2021

Since many geotechnical structures are constructed on a weathered granite layer, it is important to evaluate their characteristics. As a seismic design is the more important nowadays, the demands to estimate a shear wave velocity (V_S) based on acceptable methods are increasing. In this study, an empirical equation predicting V_S of the weathered granite layer is suggested based on the nonlinear multiple variable regression analysis whose independent variables are both SPT (Standard penetration test)-N₆₀ and chemical weathering index. It is concluded that the accuracy of the empirical equation estimating V_S of the weathered granite layer increases when it considers the chemical weathering index as an additional independent variable compared to the result of simple regression analysis using only N₆₀.

• KIPS Transactions on Computer and Communication Systems
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• v.10 no.4
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• pp.117-122
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• 2021

In recent years, human damage and loss of money due to various disasters such as typhoons, earthquakes, forest fires, landslides, and wars are steadily occurring, and a lot of manpower and funds are required to prevent and recover them. In this paper, we designed and developed a disaster drone system based on artificial intelligence in order to monitor these various disaster situations in advance and to quickly recognize and respond to disaster occurrence. In this study, multiple disaster drones are used in areas where it is difficult for humans to monitor, and each drone performs an efficient search with an optimal path by applying a deep learning-based optimal path algorithm. In addition, in order to solve the problem of insufficient battery capacity, which is a fundamental problem of drones, the optimal route of each drone is determined using Ant Colony Optimization (ACO) technology. In order to implement the proposed system, it was applied to a forest fire situation among various disaster situations, and a forest fire map was created based on the transmitted data, and a forest fire map was visually shown to the fire fighters dispatched by a drone equipped with a beam projector. In the proposed system, multiple drones can detect a disaster situation in a short time by simultaneously performing optimal path search and object recognition. Based on this research, it can be used to build disaster drone infrastructure, search for victims (sea, mountain, jungle), self-extinguishing fire using drones, and security drones.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.11
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• pp.933-940
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• 2017

The modern society is changing paradigm by the 4th industrial revolution. In these changes, the importance of geospatial information leading to the fusion and connection of persons and objects is increasing day by day. GNSS CORS(Continuously Operating Reference Station) plays a pivotal role in the geospatial information by providing basic data for surveying control points, mapping, navigation, geophysical research, and so on. On the other hand, the satellite surveying technologies are developing rapidly and it is necessary to investigate the status of the satellite surveying environment and search for future directions. In this study, the environment related to satellite survey by operation status of domestic and overseas CORS(Continuously Operating Reference Station) was tried to analyze. Through the research, The operation status of NGII and IGS CORS were presented. It was found that the availability ratio of multiple satellites to the CORS of NGII are lower than that of IGS CORS. Considering the improvement of positioning performance by using multiple GNSS, it is necessary to use multi-satellites in the future.

• The Journal of Bigdata
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• v.8 no.1
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• pp.83-97
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• 2023

Project evaluation is the process of evaluating the progress and results of a project. Smart city projects can be divided into system components (infrastructure, services, platforms), or projects can run simultaneously for multiple services. In addition, services are developed and expanded through additional projects. In order to ensure that the smart city, which is composed of various projects, proceeds in accordance with the goals and strategies, periodic project evaluation is required during the project implementation process. The smart city project evaluation system proposed in this paper is designed to provide comprehensive and objective indicators by reflecting various factors that must be considered for projects occurring in all stages of planning, design, construction, and operation of smart cities. The indicators derived from the evaluation system can be used by decision makers to determine the direction of smart city project development. In addition, it is designed so that the performance of the project can be evaluated interim before the end of the project and the feedback obtained from it can be reflected. To introduce the application method of the smart city project evaluation system proposed in this study, the evaluation system developed in this study was applied to the smart city project case of Incheon Free Economic Zone (IFEZ). Based on the evaluation results, items that can maximize the improvement effect of each smart city project item were presented, and the direction of smart city project implementation was suggested. By utilizing a smart city project evaluation system that reflects the characteristics of smart city projects that are composed of multiple projects, comprehensive planning and management of smart city projects will be possible, and this study will serve as a reference for identifying priority improvement factors for projects.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.1
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• pp.59-70
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• 2020

This study was proceeded to empirically identify the start-up support policy as an element that affects the performance of the early start-ups and measure the effectiveness of the current start-up support policy, in order to suggest the direction future policies according to the study. To accomplish this the influence of the start-up support policy on the early start-ups was analyzed, and the differences according to the industry and growth stage of the start-ups, as the characteristics of the start-ups, were identified. The research subjects collected real data of 297 start-ups of the past three years that were selected for the Initial Start-Up Package project, and performed multiple regression analysis on the influence between variables, and hierarchical regression analysis on moderating effects. The summary of the study is as follows. First, as a result of identifying the influential relationship between the start-up support policy and the performance of the start-up, sales had made a significant impact on the start-up fund, start-up mentoring, and start-up infrastructure(space), while start-up education failed to show a significant effect on the increase in sales. In terms of employment, start-up mentoring was the only field that showed a significant influential relationship. Second, as a result of identifying the moderating effect of the start-up's industry and growth stage, the industry did not have a statistically significant influence, but the interactive effect was seen in start-up education. To be more specific in terms of the sales relationship of each industry, knowledge services turned out to be helpful in improving sales, while manufacturing turned out to be effective in improving sales regardless of being supported with start-up mentoring and start-up infrastructure (space). The sales relationship regarding the start-up growth stage was identified to be statistically significant. The preliminary stage was not statistically significant, while providing start-up mentoring and start-up funding were effective for start-up stage and growing stage, respectively. On the other hand, employment did not perform a significant influence on the start-up growth stage. This study analyzes the effectiveness the start-up support policy for early start-ups, identifies the need in differentiated support policies according to the characteristics of the start-ups, and suggests implications for the direction in which future policies should be made towards.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.1
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• pp.55-73
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• 2024

Unicorn companies are attracting attention around the world as they are recognized for their high corporate value in a short period of time as an innovative business models. Their growth process presents good lessons for the startup ecosystem and have a positive impact on national economic development and job creation. However, previous studies related to unicorn companies are focused on 'event studies' and 'case studies' such as characteristics of founders, environmental factors, business models and success/failure cases of companies already recognized as unicorns rather than a multifaceted approach. The occurrence of unicorn companies and Macroscopic analysis of related factors is lacking. Against this background, this study are considering the characteristics of unicorns examined through previous research and the current status unicorns with a high proportion of technology companies, the purpose was to analyze the impact of the country's technological competitiveness, such as 'technology human resource index', 'R&D index', and 'technology infrastructure index', on the increase in unicorn companies. For statistical analysis, data published by various international organizations, the Bank of Korea, and Statistics Korea from 2017 to 2020 and unicorn company data compiled by CB Insights were used as panel data for 44 countries to be tested by multiple regression analysis. As a result of the study, it was confirmed that the number of science majors had a positive (+) effect on the increase of unicorn companies in the case of technology human resource index, and in the case of R&D index, the total amount of R&D investment had a positive (+) effect on the increase of unicorn companies, while the number of Triad Patents Families and the number of scientific and technological papers published had a negative (-) effect on the increase of unicorn companies. Finally, in the case of technology infrastructure index, it was confirmed that the number of the world's 500th-ranked universities had a positive (+) effect on the increase of unicorn companies. This study is the first to reveal the causal relationship between national technological competitiveness and unicorn company growth based on country-specific and time-series empirical data, which were insufficiently covered in previous studies. and compared to the UN's ranking of the global industrial competitiveness index and the OECD's total R&D investment by country, Korea is considered to have technological and growth potential, while the number of unicorn companies driving growth as leaders of the innovative economy is relatively small, so the research results can be used when establishing policies to discover and foster unicorn companies in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.1
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• pp.72-85
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• 2018

This study focused on cases that led sustainable urban development through the construction and utilization of organic greenery systems linking green spaces of urban peripheries with metropolitan areas. To that end, Berlin - Brandenburg's regional parks in Germany and Milan's Raggi Verdi, a radial green axis project, in Italy were selected for analysis as case studies. As frameworks for this analysis, this study has established existing infrastructure accessibility and linkage, recycling and cooperative management. The results of the case study analysis are as follows: First, the specialized spatial strategy based on the individuality of the green space outside the city rather than a uniform landscape was used as the foundation of the sustainable development plan. Second, physical linkage from the center of the city to the periphery contributed to the sustainable development of the overall metropolis by improving the economic value of the surrounding area as well as ecological and environmental values. Third, the central management system was established to reduce the administrative inconvenience caused by multiple administrative districts in the green space of urban periphery. The implications of applying the above results to Seoul, Korea are as follows. First, it is necessary to establish a differentiation strategy by re-establishing the identity of a green landscape in the urban periphery, because the green spaces of Seoul's periphery are dispersed and mostly have a repetitious mountain landscape. Also, it is necessary to actively link peripheral mountains and urban green areas to create ecological value and economic value, and ultimately to help the sustainable development of the city. Finally, building an integrated management system is required to solve fragmented green space management departments in most of the urban periphery's green spaces. In conclusion, this study shows the significant possibility that the sustainable development of a metropolis can be derived from the utilization, linkage, and management of the green space in the urban peripheries, which is extraordinary compared to normal centralized urban development.