• Journal of the Korean GEO-environmental Society
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• v.19 no.12
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• pp.15-23
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• 2018

The occurrence of soil erosions in Korea is mostly driven by flowing water which has a close relationship with rainfalls. The soil eroded by rainfalls flows into and deposits in the river and it polluted the water resources and making the rivers become difficult to be managed. Recently, the frequency of heavy rainfall events that are more than 30 mm/hr has been increasing in Korea due to the influence of climate change, which creating a favourable condition for the occurrence of soil erosion within a short time. In this study, we proposed a method to estimate the distribution of rainfall intensity and to calculate the energy produced by a single rainfall event using the cumulative distribution function that take into account of the physical characteristics of rainfall. The raindrops kinetic energy estimated by the proposed method are compared with the measured data from the previous studies and it is noticed that the raindrops kinetic energy estimated by the rainfall intensity variation is very similar to the results concluded from the previous studies. In order to develop an equation for estimating rainfall kinetic energy, rainfall particle size data measured at a rainfall intensity of 0.254~152.4 mm/hr were used. The rainfall kinetic energy estimated by applying the cumulative distribution function tended to increase in the form of a power function in the relation of rainfall intensity. Based on the equation obtained from this relationship, the rainfall kinetic energy of 1~80 mm/hr rainfall intensity was estimated to be $0.03{\sim}48.26Jm^{-2}mm^{-1}$. Based on the relationship between rainfall intensity and rainfall energy, rainfall kinetic energy equation is proposed as a power function form and it is expected that it can be used in the design of short-term operated facility such as the sizing of sedimentation basin that requires prediction of soil loss by a single rainfall event.

• The Journal of the Korea Contents Association
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• v.19 no.1
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• pp.682-695
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• 2019

In recent years, using a connected platform, companies have built and implemented a mobile viral marketing strategy to attract new customers and to have long-term relationships with existing customers. The emergence of interactive Web 2.0 has led to an explosive increase in customer engagement, and practitioners have become interested in connected platform to build close relationships with their customers. However, the study on the effectiveness of various customer influx methods using the connected platform that companies utilize for an increase of customer participation is insufficient. Based on the theoretical study of Sashi (2012), this study analyzes the actual mobile viral promotion of company A's open market shopping mall for the purpose of bringing new customers and having a long-term relationship with the new customers[1]. By analyzing the customer engagement type, the implications for the effectiveness of mobile viral promotion are suggested. First, as a result of the immediate effect of online viral promotion, promotions are partially effective in attracting new customers. Second, as a result of examining the change of customer engagement type in order to find out the long - term effect of online viral promotion, it was found that in most cases, new customers were not become satisfied customers and, Laggard Effect, which takes time to become a satisfied customer, has been confirmed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.4
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• pp.231-242
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• 2018

This experiment was carried out to study the effects of different environmental conditions and production techniques on forage productivity of Italian ryegrass (IRG) in central and southern regions of Korea from 2016 to 2017. Average dry matter yield of 27 IRG cultivation regions was 6,940kg/ha. Forage productivity of IRG have positive correlation with cultivation techniques(p<0.01) but not correlated with cultivation environments. Forage productivity of IRG have positive correlation with seeding and field management techniques(p<0.01) but not correlated with fertilization techniques. This results suggests that practices of cultivation techniques are more important than cultivation environments for increasing the forage productivity of IRG. Therefore, yield prediction techniques of IRG in Korea have to be considered the practices of cultivation techniques along with soil and climate conditions.

• Journal of IKEEE
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• v.22 no.4
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• pp.1012-1018
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• 2018

In this paper, CMOS SAR (Successive Approximation Register) A/D converter with 1.8V supply voltage is designed for IoT sensor processing. This paper proposes design of a 12-bit SAR A/D converter with two A / D converters in parallel to improve the sampling rate. A/D converter1 of the two A/D converters determines all the 12-bit bits, and another A/D converter2 uses the upper six bits of the other A/D converters to minimize power consumption and switching energy. Since the second A/D converter2 does not determine the upper 6 bits, the control circuits and SAR Logic are not needed and the area is minimized. In addition, the switching energy increases as the large capacitor capacity and the large voltage change in the C-DAC, and the second A/D converter does not determine the upper 6 bits, thereby reducing the switching energy. It is also possible to reduce the process variation in the C-DAC by proposed structure by the split capacitor capacity in the C-DAC equals the unit capacitor capacity. The proposed SAR A/D converter was designed using 0.18um CMOS process, and the supply voltage of 1.8V, the conversion speed of 10MS/s, and the Effective Number of Bit (ENOB) of 10.2 bits were measured. The area of core block is $600{\times}900um^2$, the total power consumption is $79.58{\mu}W$, and the FOM (Figure of Merit) is 6.716fJ / step.

• Journal of Korean Society of Disaster and Security
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• v.11 no.2
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• pp.1-8
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• 2018

Extreme climate phenomena are occurring around the world caused by global climate change. The heavy rains exceeds the previous record of highest rainfall. In particular, as flash floods generate heavy rainfall on the mountains over a relatively a short period of time, the likelihood of landslides increases. Gangwon region is especially suffered by landslide damages, because the most of the part is mountainous, steep, and having shallow soil. Therefore, in this study, is to predict the risk of disasters by applying topographic classification techniques and landslide risk prediction techniques to mountain watersheds. Classify the hazardous area by calculating the topographic position index (TPI) as a topographic classification technique. The SINMAP method, one of the earth rock predictors, was used to predict possible areas of a landslide. Using the SINMAP method, we predicted the area where the mountainous disaster can occur. As a result, the topographic classification technique classified more than 63% of the total watershed into open slope and upper slope. In the SINMAP analysis, about 58% of the total watershed was analyzed as a hazard area. Due to recent developments, measures to reduce mountain disasters are urgently needed. Stability measures should be established for hazard zone.

• Korean Journal of Remote Sensing
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• v.34 no.6_3
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• pp.1369-1382
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• 2018

As the number of multispectral satellites increases, it is expected that it will be possible to acquire and use images for periodically. However, there is a problem of data discrepancy due to different overpass time, period and spatial resolution. In particular, the difference in band bandwidths became different reflectance even for images taken at the same time and affect uncertainty in the analysis of vegetation activity such as vegetation index. The purpose of this study is to estimate the band adjustment factor according to the difference of bandwidth with other multispectral satellites for the application of KOMPSAT-3 satellite in agriculture field. The Spectral band adjustment factor (SBAF) were calculated using the hyperspectral satellite images acquired in the desert area. As a result of applying SBAF to the main crop area, the vegetation index showed a high agreement rate of relative percentage difference within 3% except for the Hapcheon area where the zenith angle was 25. For the estimation of SBAF, this study used only one set of images, which did not consider season and solar zenith angle of SBAF variation. Therefore, long-term analysis is necessary to solve SBAF uncertainty in the future.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.1
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• pp.1-13
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• 2019

With commercial apps popular in EU, MaaS has been emerging around the globe as a new approach to worsening urban traffic problems. In contrast, it is still mainstay in Korea simply discussing the concept and necessities of MaaS, rather than seeking for real-world solutions for the commercialization. The purpose of this research is to analyze the demand-side i1mpacts of travel time and cost changes according to MaaS adoption, and to see its commercial feasibility in Korea. The 2010 KTDB traveler's nationwide OD data is used to estimate the level of fare discount for balancing the mode shift and fare revenue changes followed by MaaS implementation. The analysis results show that MaaS leads to the increase of public transport ridership as a result of the diminishing travel cost and time, and that the time saving works more positively for ridership increase. Also, the optimum level of fare discount is estimated 2.56% without damaging the revenue. This finding reveals that MaaS impact is superior to the other single-sided public transport inventive measures since it can affect both travel cost and time reduction at the same time.

• Journal of Navigation and Port Research
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• v.42 no.6
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• pp.491-500
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• 2018

Due to changes in the distribution industry, inner harbors have been on a sharp decline in the recent past. However, through the application of the right development plans, such harbors can be revitalized into vibrant urban areas again. The importance of inner harbors has been recognized by the relevant authorities in Korea which are now pushing forward with redevelopment plans for its inner harbors. This study proposes a new approach to redevelopment plans based on the recognition that inner harbors have unique characteristics involving both inland areas and the ocean. In the study, representative inner harbors were selected and analyzed comparatively according to two distinct concepts of location: the Gateway Concept and the Central Place Concept. Based on these concepts, the conditions of the inner harbors were examined. Their location can be typed, and development directions were proposed according to their types and conditions. However, difficult points such as isolation and separation between an urban district and the harbor area, can be obstructions to their potential revival. An inner harbor needs to be considered as an intermediary, connecting place between the ocean and the city, not as another ordinary development area. In addition, a redevelopment plan should be accompanied by a strategic viewpoint to make the most of this feature.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.583-593
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• 2018

Le Corbusier is an architect known for his use of mostly white color during the Purism period. On the other hand, he actually utilized polychromy in his works while the principles behind his use of polychromy is not well defined. Through the analysis of the Pessac project, where he deliberately utilized polychromy in the exterior of housing, this study examined not only the principles behind his utilization of colors, but also the fact that this project was a laboratory to set up his architectural language and develop the method of how to employ polychromy. An analysis of this project found that he changed spaces and categorized objects using polychromy based on the white color. He also chose and used colors based on the psychophysiological experience that is related to emotions and habits. To compensate for the problems arising from the architectural space and form in the site, he used various techniques, such as camouflage, optical illusion, 'gift box' technique, and dismantlement method of volume. Therefore, polychromy is used as a method to emphasize his architectural language.

• The Journal of the Korea Contents Association
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• v.19 no.7
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• pp.335-347
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• 2019

China's 'One Belt and One Load' initiative is a mega-infrastructure project that connects China and the Eurasian Economies Area by overland and sea routes. Therefore, if it goes smoothly, It will be a new engine for economic development in China and the world, and It is expected to be a factor that will change the structure of the international economy. Especially, the Eurasian continent is likely to develop into the center of the global economy. But China's 'One Belt and One Load' initiative is not only macro and long-term, but also implies complexity, making it hard to be optimistic about development. China's 'One Belt and One Load' initiative is not only strongly promoted as a long-term national development strategy to be completed by 2049, but also strong economic complementarity between China and 'One Belt and One Load' consecutive countries. And many of the successive countries are expecting 'One Belt and One Load' construction. Therefore, there is no possibility at all. In particular, the possibility of development can not be completely ruled out, given the various policies of 'One Belt and One Load' currently being pursued by China. Even if it doesn't go smoothly, the process alone will have significant economic effects on China and neighboring countries, so it will be meaningful. With the help of information technology.