• Journal of Climate Change Research
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• v.8 no.3
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• pp.201-211
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• 2017

This study was conducted to investigate the vascular plants which can be an indicator of environmental change in Seseok of Jirisan National Park. The purpose of this study was to find out the basic information for the subalpine species. This study showed that the area had a total 295 taxa including 63 families, 177 genus, 252 species, 2 subspecies, 36 variants 5 forms and Pte-Q was 1.7. Among them, Korea endemic plants were 15 taxa such as Abies koreana. Rare plants were 14 taxa such as Viola diamantiaca. Naturalized plants consisted of 5 taxa such as Rumex crispus. The floristic regional indicator plants found in surveyed area were 72 taxa comprising 3 taxa of grade V, 7 taxa of grade IV and 24 taxa of grade III. In summary, The subalpine plants of the survey region consisted of 37 taxa including Abies koreana and Gymnadenia cucullata. As rare plants distributed in subalpine zone respond sensitively to climate change, accuracy distribution range, environmental characteristics of habitat and population dynamics of rare plants should be evaluated quantitatively.

• Journal of The Korean Society For Urban Railway
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• v.6 no.4
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• pp.279-286
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• 2018

Recently, a safety control platform to monitor the safety of train operation in real time and prevent accidents and risks through control is under study. In the initial design, DDS communication method supporting distributed network is adopted for real-time processing of large amount of data according to the integration of existing distributed safety data. However, communication between server and console inside the safety control platform is applied to existing TCP socket communication. In the case of TCP socket communication, it is possible to process data for a small system of a safety control test bed by one-to-one communication. However, if the data is expanded all over the country in the future, it becomes difficult to cope with a case where communication traffic occurs due to vast amount of data. In this paper, we propose DDS communication method to support distributed network between server and console of security control platform, and demonstrate TCP socket and DDS method, and compare throughput and speed. As a result, we have found that the scalability and flexibility are improved in case of applying DDS communication to future systems.

• Resources Recycling
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• v.28 no.1
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• pp.55-61
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• 2019

The extraction behavior of Mo(VI) and W(VI) from dilute chloride solution was investigated by employing amine (Alamine308 and TEHA) and neutral extractants (TOP) in the solution pH range from 2 to 9. W (VI) was selectively extracted over Mo(VI) by these three extractants and TEHA led to the highest separation factor. Without the pretreatment protonation of the tertiary amines, the extraction percentage of the two metal ions decreased steadily to zero as solution pH increased to 9. The extraction behavior of the metals was discussed on the basis of the distribution diagram of each metal. Alamine 308 and TEHA were much better than TOP in extracting and separating the two metal ions.

• Journal of Digital Forensics
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• v.12 no.3
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• pp.71-82
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• 2018

Using small cameras such as smartphones, criminals shoot secretly in public restrooms and women's changing rooms. And Revenge porn is also increasing. As a result social damage is increasing. Tumblr is an overseas service and it is very difficult to work with Tumbler on international legal cooperation and deletions. Thus In order to block the distribution of videos, victims must find and report the video URL themselves. But it's hard for victims who lack IT expertise to proceed those procedure. In this study, we automatically collect the URL of stored information and hash values of the images from API permlink of Tumbler blog. It is then saved as a document file with and presented to the victim. Through these technical methods, we can help victims report violations easily and quickly.

• Structural Monitoring and Maintenance
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• v.5 no.4
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• pp.463-488
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• 2018

In the last decades, research efforts have been spent to investigate the effect of prestressing on the dynamic behaviour of prestressed concrete (PSC) beams. Whereas no agreement has been reached among the achievements obtained by different Researchers and among the theoretical and the experimental results for simply supported beams, very few researches have addressed this problem in continuous PSC beams. This topic is, indeed, worthy of consideration bearing in mind that many relevant bridges and viaducts in the road and railway networks have been designed and constructed with this structural scheme. In this paper the attention is, thus, focused on the dynamic features of continuous PSC bridges taking into account the effect of prestressing. This latter, in fact, contributes to the modification of the distribution of the bending stress along the beam, also by means of the secondary moments, and influences the flexural stiffness of the beam itself. The dynamic properties of a continuous, two spans bridge connected by a nonlinear spring have been extracted by solving an eigenvalue problem in different linearized configurations corresponding to different values of the prestress force. The stiffness of the nonlinear spring has been calculated considering the mechanical behaviour of the PSC beam in the uncracked and in the cracked stage. The application of the proposed methodology to several case studies indicates that the shift from the uncracked to the cracked stage due to an excessive prestress loss is clearly detectable looking at the variation of the dynamic properties of the beam. In service conditions, this shift happens for low values of the prestress losses (up to 20%) for structure with a high value of the ratio between the permanent load and the total load, as happens for instance in long span, continuous box bridges. In such conditions, the detection of the dynamic properties can provide meaningful information regarding the structural state of the PSC beam.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.823-824
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• 2016

In general, distribution board, panel board and motor control center can be installed over a wide area such as residence of group, building, schools, factories, ports, airports, water service and sewerage, substation and heavy industries that are used to supply converts the voltages extra high voltage into optimal voltage. There are electrical accidents due to rise of contact temperature, loose contact of bus bar, deterioration of the contact resistance, overtemperatue of the bus bars. In this paper, we propose bus bar joints monitoring system with loose connection of bus bar, measuring the joint resistance of busbars and monitoring internal and external heat. The proposed system can be reduced the electrical accidents by maintenance of busbar joints and the temperature of the conductive contact surface of busbars.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.933-936
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• 2014

The government has the duty to prevent abuses of monopoly and promote competition in order to maximize consumer welfare. In order to promote competition we have to address the asymmetry in the information as possible and to ensure consumer choice. The subsidy seems to reduce the burden on the consumer service charges and handset prices but it virtually distort the market through price discrimination. The government caused the principal-agent problem by avoiding their appropriate role to prevent distortion of the mobile telecom market. The money used as subsidy could be transferred to down the price of cell phone and charges and it would be a benefit to consumers. Separate notice of subsidies by Mobile Communications Terminal Distribution Structure Improvement Act is a developed policy but it was too late. It, the market price close to that from perfect competition structure, is plausible, ultimately.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.917-920
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• 2014

In Korea mobile phone subscribers exceeded 1 million people in 1995, and ten million people in 1998. Prevalence of the mobile phone increased dramatically over 110% compared to the population. And all family members including children and students use one or two mobile terminal. Mobile phone is obviously necessary good more than washer, vacuum cleaner, passenger car. Our daily life with mobile communication are conveniently positioned, but communication related costs including the price of the device has become a big burden on the household. But the government does not seem to do the right role at the right time to prevent the failure of the market to further maximize consumer welfare and social welfare through fair competition. This principal-agent problems exist especially in perspective of joint use of the mobile communication network, number portability, separation of phone distribution and phone service and network neutrality among in mobile communication policies since the early 1990s up to now.

• Journal of Digital Convergence
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• v.17 no.9
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• pp.399-406
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• 2019

The purpose of this study is to examine the relationship between corporate reputation and the profitability. In this study, Big Data Analysis was conducted for Hyundai Motor, Shinsegae Department Store, SK Telecom, and Amorepacific to solve research problems. The results of this study show that the effect of each corporate reputation on the profitability is different according to the company. For products such as Hyundai Motor and Amorepacific that are used directly by consumers, the corporate reputation formed by the comments was more influential. In addition, distribution Service company such as Shinsegae Department Store showed more influence by online news. On the other hand, SK Telecom did not have a significant effect on profitability. Based on the results, this study emphasizes the importance of online news and comments on corporate reputation management, and aims to contribute to establishing an efficient reputation management strategy by examining the relationship between corporate reputation and profitability.

• Journal of Korean Society of Rural Planning
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• v.25 no.3
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• pp.115-128
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• 2019

The A1B scenario predicts that the mean air temperature of South Korea will rise up to $3.8^{\circ}C$ by 2071. However, the effects of ecosystem services are declining because of various environmental problems, including climate change, land use change, stream intensification, non-point pollution, and untreated garbage. Moreover, horticultural sites which have various ecosystem services suffer highly absorbed heat from the heat island phenomenon associated with climate change. Therefore, we analyzed the heat island phenomenon occurring in an protected horticulture estimated area in Saemanguem, South Korea. Using an advanced measurement method, we examined the air temperature change derived from water channels as well as open spaces. The CFD analysis of coverage ratio 85% design showed wind speed of 2.09 m/s and temperature of $38.07^{\circ}C$. At a coverage ratio of 70%, the wind speed was improved to 2.61 m/s and the temperature was improved to $36.89^{\circ}C$. In Alternative 2 with wetlands and trees, the wind speed was 2.71 m/s and the temperature was $35.90^{\circ}C$. When the coverage ratio decreases to 55%, the wind speed increases showing 3.06 m/s and the temperature decreases showing $35.18^{\circ}C$.