• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.310-315
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• 2017

Although studies evaluating the effects of the blasting vibration on the adjacent structures from various angles have continued, cases of securing the safety of the adjacent buildings and researching the proper blasting method for the field condition by analyzing the vibration waveform of the measuring field while performing the open pit blasting are poor. Therefore, it is necessary to present a remedy for blasting pattern selection through test blasting that is appropriate for field conditions, and is economical and efficient. In this study, open pit blasting work was conducted based on the separation distance applied according to the standard blasting method by test blasting and the vibration regulation standard in the road expansion construction site to measure the blasting vibration value, and the vibration prediction equation by blasting methods was examined using a regression analysis computer program to calculate K, N, and R of the confidence level 95%. By setting the blasting allowed vibration standard of the test blasting target area to 0.3cm/sec, and the charring weight and blasting method by the separation distances according to the blasting vibration estimation equation of the open pit blasting guideline and the blasting vibration estimation equation of the test blasting were compared/analyzed, it was possible to identify the factors that increased the working expenses. In addition, the measurement and analysis of the adjacent structures during open pit blasting and the blasting vibration were performed after selecting the most adjacent structure to the open pit blasting spot to analyze the problems on the test blasting procedure and analysis method in the open pit blasting design/construction guidelines, which appeared in the process of completing open pit blasting construction, and a remedy is presented.

• International Journal of Highway Engineering
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• v.13 no.4
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• pp.81-91
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• 2011

This study was conducted to evaluate the necessity of the anchor lug system in continuously reinforced concrete pavement(CRCP) by comparing longitudinal displacements of CRCPs with and without anchor lugs, and to investigate the effect of horizontal cracking on CRCP performance by measuring the vertical displacements. The measurements before and after the anchor lug section was separated were conducted for 12 days in June, and for 14 days in August after the abrupt displacements according to cutting disappeared, respectively. This short term measurement results showed that when anchor lugs were installed, a daily displacement variation at any location was less than 0.1mm; therefore, longitudinal movements were negligibly small. When there were no anchor lugs, longitudinal displacements mainly occurred near the free end and the displacement variation was small; therefore, an expansion joint system seems to be employed at a CRCP terminus without installing anchor lugs. However, further studies are needed to verify the terminus behavior due to annual temperature changes. The horizontal crack width variation was ignorable and did not affect the vertical displacement of the slab. Therefore, the horizontal crack did not delaminate the slab and did not seem to reduce the structural capacity and performance of CRCP.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1603-1614
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• 2010

As the Kyoto protocol and Bali road-map, our country is expected to be included to the emission reduction controlled country of greenhouse gas, so we are now urgent situation to take an action in the level of government. In this research, environment friendly rail logistics and combined transport were treated to meet with the green growth policy of our government. Major problems of Ui-wang ICD suggested in this research are short of yards, unutilized public CY, inconvenience use by non-share holders. It is necessary to improve rail logistic infrastructure, that is, additional expansion of yard, direct operation by KORAIL and regular unloading system are needed. such improvement can not be solved just by the endeavor of business body. Rail logistic infra & Integrated freight terminal has a tendency of SOC, which require tremendous amount of investment, so there are some limit in doing by private sector itself, now it's time to do by the government level. The improvement of rail logistic infrastructure in the level of government is possible by the policy of environment friendly green logistic support which is related with Logistic Policy Basic Law, so government should prepare detailed directives to activate Integrated freight terminal.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.325-337
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• 2007

Illegal slash-and-bum fields and slash-and-bum farmers in Korea had increased in spite of Japanese Joseon Government's strong regulations and clearance measures, and land reform after the 1945 Liberation of Korea until 1970s. This study is to inquire into the necessary and sufficient conditions to disappear entirely the matters from 1974 to 1979 that illegal slash-and-bum fields and slash-and-burn farmers continued long in existence until the early 1970s. The findings are as follows; Firstly, the population pressure to agricultural lands that main factor of generation of illegal slash-and-bum fields had decreased rapidly because the rural populations and less income farmers have decreased after 1967. Especially, the decrease of the rural populations had never seen to the 1970s. It is recognised that the social condition for the success in 1970s. Secondly, the continuous economic growth from the early 1960s enabled the Korean government to solve the matter through the sufficient financial investment from the Government. For example, the gross national product (GNP) and the government budget in 1974 increased around 25 times after 1960. It is recognised that the economic condition for the success in 1970s. Finally, it was enabled to remove the concealment from the slash-and-bum farmers and to monitor illegal re-cultivation thoroughly because the development of forest inventory technique using an aerial photograph and the expansion of road facilities. It is recognised that the technical condition for the success in the 1970s.

• International Journal of Highway Engineering
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• v.17 no.3
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• pp.85-95
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• 2015

PURPOSES : Recently, bonded concrete overlay has been used as an alternative solution in concrete pavement rehabilitation since its material properties are similar to those of the existing concrete pavements. Deteriorated concrete pavements need rapid rehabilitation in order to prevent traffic jams on Korean expressways. Moreover, speedy and effective repair methods are required. Therefore, the use of bonded concrete overlay with ultra-rapid hardening cement has increased in an effort to reopen promptly the expressways in Korea. However, mobile mixer is required for ultra-rapid hardening cement concrete mixing in the construction site. The use of mobile mixer causes various disadvantages aforementioned such as limitation of the construction supply, open-air storage of mixing materials, increase in construction cost, and etc. In this study, therefore, hydration accelerator in-situ mixing on polymer modified concrete produced in concrete plant is attempted in order to avoid the disadvantages of existing bonded concrete overlay method using ultra-rapid hardening cement. METHODS : Bonded concrete overlay materials using ultra-rapid hardening cement should be meet all the requirements including structural characteristics, compatibility, durability for field application. Therefore, This study aimed to evaluate the application of hydration accelerator in-situ mixing on polymer modified concrete by evaluating structural characteristics, compatibility, durability and economic efficiency for bonded concrete overlay. RESULTS : Test results of structural characteristics showed that the compressive, flexural strength and bond strength were exceed 21MPa, 3.15MPa and 1.4MPa, respectively, which are the target strengths of four hours age for the purpose of prompt traffic reopening. In addition, tests of compatibility, such as drying shrinkage, coefficient of thermal expansion and modulus of elasticity, and durability (chloride ions penetration resistance, freezing-thawing resistance, scaling resistance, abrasion resistance and crack resistance), showed that the hydration accelerator in-situ mixing on polymer modified concrete were satisfied the required criteria. CONCLUSIONS : It was known that the hydration accelerator in-situ mixing on polymer modified concrete overlay method was applicable for bonded concrete overlay and was a good alternative method to substitute the existing bonded concrete overlay method since structural characteristics, compatibility, durability were satisfied the criteria and its economic efficiency was excellent compare to the existing bonded concrete overlay methods.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.1
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• pp.85-91
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• 2020

The descendants of Jang, Chang-woo(張昌雨) reconstructed the Mangwijung (晩歸亭), which is currently located at Seha-dong, Seo-gu, Gangju Metropolitan City, in the context of succeeding the work of their ancestor. This study investigated the management viewpoint of Mangwijung that has been altered in going through the reconstruction and repairs processes, and examined the chronological history for a landscape of the Mangwijung Garden. First, in the Mangwijung Garden, three gazebos such as Mangwijung, Seubhyanggag(襲香閣) and Mukamjeongsa(墨庵精舍) stand in a row with three bridges between each of them in the middle of a wide pond. This is a group of gazebos that is a quite unique structure. Second, Hyowoodang(孝友堂) Jang, Chang-woo (張昌雨) built Mangwijung as a role of thatched cottage in order to teach younger students and enjoy the arts in his later life. The Mangwijung was reconstructed by the descendants of Jang, Chang-woo at the collapsed place later on in order to commemorate the achievements of their ancestor. By the way, it was revealed that the management of Mangwijung has been altered during the process of reconstruction. Third, when comparing the current appearance with those depicted in the 8 scenic views(八景) by Jang, Chang-woo and the literary works of his descendants, it was confirmed that the landscape and shape of the pond were damaged due to a road expansion caused by a construction of Seubhyanggag and Mukamjeongsa as well as an advancement of the city. Fourth, it is speculated that the pond of Mangwijung Garden is probably a spring not a reservoir to store the water stream that flows in.

• The Journal of the Korea Contents Association
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• v.13 no.4
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• pp.440-451
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• 2013

Advancement of science technology, combined with other technologies including smart clothing, enables value added product developments and market creation. Accordingly, it became necessary to identify technology trends promptly and to prepare future technology road map. For this purpose, many bibliometric analysis using thesis and patents have been made. However, few such attempts are made in clothing study. Thus, the study examined the latest technology trends and future technology development directions of smart clothing from empirical bibliometric analysis based on smart clothing patent documents. In addition, comparative analysis was made about the market leadership and technology development capability of core sectors by countries utilizing market reach index expressed as patent families and technology development index. The study revealed that overall smart clothing technology development trends has been continuously increasing since 2000. Also the results confirmed that it is in the development stage from the fact that each year the number of patents and patent applicants in portfolio analysis also has been increasing. In addition, comparative results of patent market share and market reach index, with the highest in electronics/ICT technology sectors, indicated that this is the technology sector with competitive acquisition of comparatively advanced technology and market expansion. The analysis methodology of economic value of technology including the presented market reach index in this report is expected to be utilized in the process to identify the current positioning of core technology and future development direction.

• Convergence Security Journal
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• v.14 no.1
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• pp.23-32
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• 2014

Quantitative rise and This study carried out qualitative research by utilizing NVivo 10 focusing on the contents of mass media such as newspaper or internet on the presidential security service up to the Park Geun-hye government from the 3rd Republic of Korea, which was established the presidential security service. The aim is to present opinion so that the presidential security organization can strengthen capability and function within the governmental organization down the road based on the contents of categories, which were elicited through this. First, there is a need of solidifying the internal stability with the expansion in the activity sphere of organization and of externally approaching the public with removing sense of difference caused by offering personal protection only to some of the privileged class in the meantime. Second, it is the foundation of a reason related to crime in a cause for Discharge by Authority pertinent to "law on security for president and others" in Article 10 in order to prevent a criminal act of having abused the task characteristic and the position superiority or an external pressure act related to intervention in rights. Third, there is a need of making it recognized as very important organization with putting differentiation from other organizations of the government by providing the disciplinary level more strictly than "disciplinary order on public officials" based on particularity and importance dubbed presidential security service along with correspondingly applying "disciplinary order on public officials" in Article 31 in accordance with "enforcement ordinance of law on security for president and others" in terms of service negligence and false-information report in relation to task performance.

• Journal of Korean Society of Transportation
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• v.34 no.4
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• pp.304-317
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• 2016

The advancement in technology including transportation and information communication has accelerated the flow of supplies, and the importance of the national logistics policy has increased following the expansion of the regional range of logistics to a national range. The rapid growth of the domestic logistics market results in the deficit of logistics facilities, inefficient operation of logistics facilities, and a complicated distribution structure. It has precipitated a plan aimed at efficiency improvement by building base logistics facilities, but this market is now undergoing difficulties due to low performance. Many studies on the revitalization of base logistics facilities have been conducted, but a causal analysis focusing on the function overlap of private logistics businesses has been absent. Therefore, this study has analyzed the function overlap of logistics facilities and the irrationality of the system, which resulted from the lost function of Inland Freight bases in the Yeongnam region. By suggesting the cause of disuse of base logistics complexes from the function overlap in the ground transportation of domestic freight, the study can provide the policy implication for the national logistics infrastructure.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.471-476
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• 2021

Personal mobility (PM) is a new concept of transportation used by one or two people using electricity. Personal transportation aims to move quickly and conveniently over an ambiguous distance that is too close to the destination and too far to walk. In particular, as electric kickboard sharing services have become more common in recent years, they are receiving great popularity from citizens. However, it is necessary to come up with an alternative solution as it is acting as a risk not only to users but also to pedestrians and road drivers. Therefore, in order to present measures to establish and improve a safe personal mobility utilization environment, this research was conducted as follows. First, based on GPS data from shared electric kickboards, the usage status in everyday life was examined and analyzed in detail. Second, it is convenient to rent and return shared electric kickboards directly to applications regardless of time, and it is highly accessible to rent them from their location and reach their destination. Based on these findings, this study suggests that careful access to rental and return could have a more positive effect on users and pedestrians by installing a cradle in a place where there is more use than disorderly device placement and expansion.