• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.10
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• pp.902-909
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• 2015

In this paper, monovision based relative navigation for a satellite proximity operation is studied. The chaser satellite only uses one camera sensor to observe the target satellite and conducts image tracking to obtain the target pose information. However, by using only mono-vision, it is hard to get the depth information which is related to the relative distance to the target. In order to resolve the well-known difficulty in computing the depth information with the use of a single camera, the active contour method is adopted for the image tracking process. The active contour method provides the size of target image, which can be utilized to indirectly calculate the relative distance between the chaser and the target. 3D virtual reality is used in order to model the space environment where two satellites make relative motion and produce the virtual camera images. The unscented Kalman filter is used for the chaser satellite to estimate the relative position of the target in the process of glideslope approaching. Closed-loop simulations are conducted to analyze the performance of the relative navigation with the active contour method.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.3
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• pp.220-227
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• 2015

Ultra high performance concrete (UHPC) uses large quantities of steel fiber, silica fume, filler and superplasticizer for a low water-to-binder ratio (W/B). Despite of exceptional mechanical performances, UHPC exhibits increased viscosity due to the adoption of silica fume and its fabrication cost is costlier than ordinary concrete because of the use of large quantities of expensive materials. Following, this study evaluates the mechanical properties of 180MPa-UHPC using zirconium silica fume (Zr) instead of silica fume with respect to the quantity and type of superplasticizer (SP) and the size of filler. The results reveal that the Zr-UHPC using W/B of 20%, 100% of Zr, amount of SP-L of 2 to 3% and $4{\mu}m$-filler with steel fiber in 1.5 vol.% can develop better fluidity than the traditional mix composition using silica fume and secure a compressive strength higher than 180 MPa. In addition, the proposed mix composition is shown to enable a reduction of the fabrication cost by 33% compared to traditional UHPC.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.5
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• pp.599-607
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• 2015

The purpose of this study is to reproduce long-term wave fields in coastal waters of Korea based on wave hind-casting modelling and discuss its applications. To validate wind data(NCEP, ECMWF, JMA-MSM), comparison of wind data was done with wave buoy data. JMA-MSM predicted wind data with high accuracy. But due to relatively longer period of ECMWF wind data as compared to that of JMA-MSM, wind data set of ECMWF(2001~2014) was used to perform wave hind-casting modelling. Results from numerical modelling were verified with the observed data of wave buoys installed by Korea Meteorological Administration(KMA) and Korea Hydrographic and Oceanographic Agency(KHOA) on offshore waters. The results agree well with observations at buoy stations, especially during the event periods such as a typhoon. Consequently, the wave data reproduced by wave hind-casting modelling was used to obtain missing data in wave observation buoys. The obtained missing data indicated underestimation of maximum wave height during the event period at some points of buoys. Reasons for such underestimation may be due to larger time interval and resolution of the input wind data, water depth and grid size etc. The methodology used in present study can be used to analyze coastal erosion data in conjunction with a wave characteristic of the event period in coastal areas. Additionally, the method can be used in the coastal disaster vulnerability assessment to generate wave points of interest.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7485-7493
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• 2015

With the popularity of Korean Wave, making cultural goods specific for Hallyu tourists is getting more important. However, there are mainly daily life goods using celebrity character-based ones. Remarkably, there are only a few cultural goods especially in practicality-based clothing category. In particular, few cultural goods related to children's wear have been developed. Therefore, if children's wear is developed as Korean Wave cultural goods considering Chinese consumers' pattern and Korean Wave cultural goods, it will be helpful for revitalizing the Korean Wave and Korea's fashion market. In this regard, the purpose of this study is to develop children's wear design as Korean Wave cultural goods, thereby presenting empirical research results and fulfilling its following objectives: First, it is to identify the concept of Korean Wave cultural goods, to analyze the current status to finally establish data to develop Korean Wave cultural goods needed at this time. Second, it is to make real-life size works through development of designs to provide the empirical data for Korean Wave cultural goods market. For the research method and contents the review of the previous research, in-depth interview for qualitative research, and empirical research using market research and development of work were performed. Through the final research outcomes, Korean Wave cultural goods, the children's wear that can meet the consumer's needs were presented as empirical data. The study can be used as basic data for domestic fashion market and cultural product market and it is meaningful as a reference for the analysis on the Chinese consumers' needs.

• Journal of Korea Technology Innovation Society
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• v.20 no.4
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• pp.1212-1242
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• 2017

In this study, the effectiveness of the innovative company certification system, which is one of the important means of the SME innovation promotion policies, was examined in terms of technological innovation activity and performance. To this end, we used the results of 'SME Technology Statistical Survey' conducted by the Small and Medium Business Administration and the Korea Federation of Small and Medium Business in 2013~2015 to compare the innovative SMEs that have received the certifications such as Venture Certification, Innobiz Certification, and Mainbiz Certification with the general SMEs that did not. As a result, it was found that the innovative SMEs have comparative advantage in many detailed indicators related to the technological innovation activity and performance. However, the ratio of external use of R&D expenditure, the number of technology development attempts and the number of successes were not different according to the survey year, so it is necessary to strengthen the follow-up management of the system. On the other hand, the proportion of self-procurement R&D expenditure of the general SMEs was significantly higher than that of the innovative SMEs in all three-year surveys. Therefore, it is necessary to regulate the government funding for the innovative SMEs to be used as a complementary material, not as a substitute for their own R&D investment. In addition, the technological innovation activity and performance of a company were more influenced by the size of the company and the participating industry rather than by the certification, so it is necessary to consider it when establishing the technology innovation promotion policies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3099-3110
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• 2015

Recently, there are so many music school graduates. In addition, there are many private music institutes. For this reason, there is a fierce competition in music education market. In the past, those who worked in music education market earned big money and so many parents wanted their girls and boys to learn playing a piano and other musical instruments. In the recent times, however, birth ratio was reduced dramatically in Korea and parents do not want their children to learn musical instruments due to economic depression and deteriorated music market. Eventually, the size of music education market was diminished dramatically and the competition in music education market is getting fiercer. Therefore, it is difficult to expect good performance in music education market without having an improved management system. In this respect, this study aims to understand what main factors have an impact on business performance in music institutes. The main areas studied in this paper include successful factors, reason why they start up a business, and successful management factors. The survey of this study targeted music institute owners. Based on the surveyed results, for the owners of the music institute, the method of the venture management approach, in other words, the application of the marketing knowledge, the consideration of the company system, the application of the smart technologies, etc., has been presented.

• Journal of Korea Water Resources Association
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• v.51 no.12
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• pp.1181-1194
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• 2018

This study suggests a novel approach of estimating stream flow discharge using the Synthetic Aperture Radar (SAR) images taken from 2015 to 2017 by European Space Agency Sentinel-1 satellite. Fifteen small to medium sized rivers in the Han River basin were selected as study area, and the SAR satellite images and flow data from water level and flow observation system operated by the Korea Institute of Hydrological Survey were used for model construction. First, we apply the histogram matching technique to 12 SAR images that have undergone various preprocessing processes for error correction to make the brightness distribution of the images the same. Then, the flow estimation model was constructed by deriving the relationship between the area of the stream water body extracted using the threshold classification method and the in-situ flow data. As a result, we could construct a power function type flow estimation model at the fourteen study areas except for one station. The minimum, the mean, and the maximum coefficient of determination ($R^2$) of the models of at fourteen study areas were 0.30, 0.80, and 0.99, respectively.

• The Journal of the Korea Contents Association
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• v.19 no.5
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• pp.48-63
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• 2019

We tried new analysis including social network analysis(SNA) on the transaction network centered on electronic companies using more than 50 thousand company transaction data obtained from Korean enterprise data (KED) for the year of 2015. We found 97 clusters having more than 10 firms and remarkable 13 clusters having more than 90% sales of the electronic industry in Korea. Clusters are the groups of companies having most of their transactions in the clusters they belong to. We found 5 clusters have 83% of sales in the electronic industry. Most of clusters have main single firms having most of the sales in each clusters except a few clusters. However, we found a few firms to have high rear production linkage effect and found the firms with high linkage effect specially for the small and medium size enterprise (SME). The companies with high production linkage (specially on SMEs) should be managed in terms of (SME) growth policy. The last firm group consisting of the small clusters with less than 10 firms has high employment coefficients. The clusters or company having high production linkage effect on this last firm group should be noted in the terms of employment policy. We also note that there exist the firms with the high value of betweenness coefficients meaning high potential of technology development. They should be managed carefully in terms of technology development policy.

• Korea Science and Art Forum
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• v.19
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• pp.405-415
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• 2015

Recently the development of China has attracted all over the world, many scholars of different areas are interested in Chinese Culture and Chinese Market. After sixties of last century development of the economic of the South Korea closer to modernization, but there are many problems, one of them is the urban living style boasts of the features of concentration. Because of this phenomenon the lack of housing space become more serious. It also come to be a social problems. Therefore narrow residential area become inevitability. At the same time, effective utilization of housing space become a demand. Especially for those families with limited living space, it's meaningful for them. Between the China and the South Korea. Chinese have the same situation too, the different is kitchen space of chinese is closed. It means they have to cook in limited space. With increased supplies and more small appliances, an inevitable requirement is opening out the kitchen space, but unreasonable furnishings and living space reduces the efficiency of the kitchen, which has led to the discontent of users. From this, base on the investigation and analysis of diet&living space of most chinese apartment, and through differences kinds and places of storage items. With them I would combine the food culture and feature of storage space of China to solve problems of the efficiency of the kitchen.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.386-388
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• 2021

According to data from the World Meteorological Organization (WMO) in 2019, the global average temperature between 2015 and 2019 increased by 1.1℃ compared to the pre-industrial period (1850-1900). If the average temperature rises by 1.5℃, the occurrence of natural disasters such as extreme high temperatures, heavy rains and droughts will increase, and this change will intensify depending on the speed and size of warming. Due to the effects of global warming, global surface temperatures have gradually risen, and tropical fruits, which could only be grown in tropical regions, can be seen in Korea. According to the 5th report released by the IPCC of the Intergovernmental Panel on Climate Change under the United Nations, the world's average temperature will rise 3.7 degrees Celsius at the end of the 21st century (2081-2100). If the temperature rises gradually, it is believed that Korea's current cultivation area, which can produce good quality fruit, could be turned into an unfavorable area in the future. This paper aims to develop a plant cultivation system that utilizes Arduino to provide a customized environment for the growth of plants desired by growers.