• Journal of Korean Society of Steel Construction
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• v.17 no.5 s.78
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• pp.569-580
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• 2005

The postbeam joint connection of the existing steel structure moment flexible frame system did not produce sufficient seismic resistance during the earthquakes in Northridge and Kobe, and it sustained brittle fracturing on the joint connection. This study was performed to execute the high-tensile bolt share connection of H-beams web and the full-scale experiment as a parameter of the existing reinforcement of H-flange rib, by making the shape of the existing joint connection. This experiment was performed to determine the extent of the decrease of the number of high-tensile bolts and how to improve workability of the two-phase shear connection of web beam. In addition, this study was performed to enhance the seismic resistant capacity through the enforcement of rib plates. As a result of the experiment of two-phase shear connection of H-beam web and of joint connection to be reinforced by rib plates, the results of this study showed that the initial stiffness, energy-dissipation capacity, and rotational capacity of plasticity was higher than the existing joint connection. As to the rate of increasing the strength and deformation capacity, there were differences between the tension side and compression side because of the position of shear tap. However, as a whole, they have shown excellent seismic resistant capacity. Also, all the test subjects exceeded 4% (rate of delamination), about 0.029 rad (total plastic capacity), and about 130% (maximum strength of joint connection) of fully plastic moment for the original section. Accordingly, this study was considered as it would be available in the design more than the intermediate-level of moment flexible frame.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.203-215
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• 2015

The study aims to identify the degree and types of spatial recessions in Si/Gun and Eup/Myun units within Chungcheong region in South Korea to contribute to the efforts being made to diagnose the rural recession and the potentials. To this end, we analyzed 27 Sis and Guns to identify the degree of recession and potentials of rural areas in Chungcheong region. We also carried out the diagnosis and K-Means Clustering on 274 Eups and Myuns, smaller administrative units, to figure out the types and characteristics of the rural recessions. In case of the analysis targeting the Sis and Guns, a relatively high degree of rural recession was found in Cheongyang, Seocheon and Taean for Chungcheongnam-do, and in Danyang and Goisan, as well as in Boeun, Okcheon and Youngdong - which are collectively called as 'Southern 3 Areas in Chungcheongbuk-do' as they are conventionally known by their high degree of rural recession. According to the results of the clustering analysis carried out on the 166 Eups and Myuns, there were five outstanding clusters. They were; areas with housing deterioration (29), areas with poor economic foundation (16), areas with poor accessibility to central areas (42), areas with poor residential environment (51) and areas with aged population (28). The findings and results of the present study are likely to serve as a basis for the design and enforcement of forthcoming rural area activation policies. Also, it would be highly recommended that a more comprehensive diagnosis is taken from a community-level perspective and policy suggestions and strategies tailored for rural communities are further discussed.

• Journal of the Korean GEO-environmental Society
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• v.18 no.4
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• pp.23-29
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• 2017

As the Enforcement Ordinance of Environmental Policy Act was revised in 2013, Total Organic Carbon (TOC) was added as an indicative parameter for organic matter in Water and Aquatic Ecosystem Environmental Criteria. Under these imminent circumstances, a regulatory standard is needed to achieve the proposed TOC limitation control water quality from the STP (Sewage Treatment Plant). In this study, a electrolysis utilizing the electrochemical reaction was investigated in lab-scale experiments for the treatment of TOC in sewage effluent. TOC reduction by a electrolysis was investigated response surface methodology using the Box-Begnken methods were applied to the experimental results. A central composite design was used to investigate the effects of the independent variables of electrode space ($x_1$), current density ($x_2$) and electrolyte concentration ($x_3$) on the dependent variables removal efficiency of TOC (y). The optimal conditions for electrolysis were determined: electrode space, current density and electrolyte concentration were 50 mm, $10.3mA/cm^2$ and 0.1M, respectively. Statistical results showed the order of significance of the independent variables to be electrode space > current density > electrolyte concentration.

• Fire Science and Engineering
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• v.15 no.1
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• pp.100-107
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• 2001

A Interior material, a main cause of fire-growth and generating toxic gas when it burns, should be dealt with great care in life safety design. Nonetheless, it has been used recklessly with undue attention to its contribution to fire in particular in entertainment occupancy and causes many victims in fire. Therefore, this study attempts to examine the current use of interior material in Korea and find out what to be improved and enhanced in terms of related regulations. Based on the comparison and analysis of the Korea regulation with those of advanced nations, suggestions are made for an effective and efficient improvement and complement to the current system. What can be suggested from this study are as follows. The use of interior material should be controlled under the unified regulation of fire-safety codes. Code should be set up so that the current construction enforcement should be applied in retroactive to those entertainment buildings that obtained a license prior to the implementation of the system certifying that the building is fire-resistant and fire-protective. The legislation should be made to control the fire-protection facilities of small-sized, underground entertainments. It should be obliged to present the blueprint displaying the use of interior material at the time of changing occupancy. Or, it should be compelled to report changes that go way without permit to the administrative office. A compulsory provision should be set up to have a fire-resistant performance to movable furniture. The classification index designating the fire hazard of interior material by flame spread rate and smoke toxicity and its test method should be established.

• Journal of Korean Society of Transportation
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• v.18 no.6
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• pp.7-17
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• 2000

The Purpose of this study is to test the effectiveness of Special Transportation Management Zone system (TZ) when it is applied to Dongdaemoon commercial zone located in downtown Seoul. The study consists of two Parts ; the legal components of TZ and the case study on Dongdaemoon district. The case study includes the analysis of current traffic situation on the study zone, the design of implemention alternative for each component of TZ, the framework of impact analysis system, and the analysis results. The study finds, if 2,000 won mandatory parking fee on drivers parking in the buildings only with over 10 parking spaces and over 3.000$m^2$ in floor area, strong illegal parking enforcement, and Pro-hibition of parking passenger cars whose last digit plate number matches with the last digit of date, are implemented in the zone simultaneously, the traffic speed increases to 20.56km/h which is above the target set in the zone. In conclusion, we find that TZ2 can be an effective tool relieving traffic congestion in Seoul, and that it is necessary for introducing TZ in Seoul that relevant laws should be revised and expecting problems should be overcome.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.49 no.4
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• pp.31-41
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• 2012

The law enforcement agencies in the worldwide are confiscating or retaining computer systems involved in a crime/civil case, if there are any, at the preliminary investigation stage, even though the case does not involve a cyber-crime. They are collecting digital evidences from the suspects's systems and using them in the essential investigation procedure. It requires much time, though, to collect, duplicate and analyze disk images in general crime cases, especially in cases in which rapid response must be taken such as kidnapping and murder cases. The enterprise forensics, moreover, it is impossible to acquire and duplicate hard disk drives in mass storage server, database server and cloud environments. Therefore, it is efficient and effective to selectively collect only traces of the behavior of the user activities on operating systems or particular files in focus of triage investigation. On the other hand, if we acquire essential digital evidences from target computer, it is not forensically sound to collect just files. We need to use standard digital evidence container from various sources to prove integrity and probative of evidence. In this article, we describe a new digital evidence container, we called Xebeg, which is easily able to preserve collected digital evidences selectively for using general technology such as XML and PKZIP compression technology, which is satisfied with generality, integrity, unification, scalability and security.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.3
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• pp.130-139
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• 2016

A frequency of earthquake occurrence in the Republic of Korea is increasing over the past few decades. In this situation, an importance of earthquake prevention comes to the fore because the earthquake does damage to structures and causes severe damage of human life. For the earthquake prevention, a real-time vibration measurement for structures is important. As an example, the United States of America and Japan have already been monitoring real-time earthquake acceleration for the important structures and the measured acceleration data has been managed by forming database. This database could be used for revising the seismic design specifications or predicting the damage caused by earthquake. In Korea, Earthquake Recovery Plans Act and Enforcement Regulations are revised and declared lately. Ministry of Public Safety and Security is constructing a integrated management system for the measured earthquake acceleration data. The purpose of this research is to develop a real-time vibration monitoring and analysis system for structures which links to the integrated management system. The developed system contains not only a monitoring function to show real-time acceleration data but also an analysis system to perform fast fourier transform, to obtain natural frequency and earthquake magnitude, to show response spectrum and power spectrum, and to evaluate structural health. Additionally, this system is designed to be able to link to the integrated management system of Ministry of Public Safety and Security. It is concluded that the developed system can be useful to build a safety management network, minimize maintenance cost of structures, and prevention of the structural damage due to earthquake.

• Journal of Korean Society of Disaster and Security
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• v.13 no.1
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• pp.13-23
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• 2020

In 2005, Urban railway seismic design was introduced in Rep. Of Korea, and many studies on seismic performance evaluation and reinforcement methods were conducted. In accordance with the Enforcement Decree of the Earthquake Disaster Countermeasures Act issued in March 2009, during April 2010 to October 2013, some of local governments established detailed evaluation and reinforcement measures for seismic performance of the urban railway underground structure. Afterwards, the seismic performance reinforcement of the existing urban railway structures was conducted for the sections that a long period of used until the end of 2018, and the reinforcement works are carried out by various methods using the previously studied methods. However, various reinforcing materials and construction methods using have been studied, but the classification research on the construction methods currently applied to reinforcement construction of urban railways is insufficient. The purpose of study is to analysis the cases currently applied to seismic reinforcement construction and to show the characteristics of each construction method, the reasons for its application and problems.

• The Journal of Society for e-Business Studies
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• v.25 no.4
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• pp.15-32
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• 2020

Increasing uncertainties in the technological innovation environment and increasing technology competition also present new challenges in terms of industrial technology security. Therefore, the purpose of this study was to identify the direction of policy change necessary for the improvement of related policies in the future by examining the importance and implementation of the government's industrial technology security support policies for small and medium-sized enterprises engaged in industrial technology innovation activities. As a result of the analysis, first of all, small and medium-sized enterprises that responded to the government's industrial technology security support policy were perceived to be less performing than the importance of the program. These results can be said to mean that selective budget expansion for related policy programs may be necessary, along with efforts to improve the quality of each program. Second, an analysis of the differences in group recognition between new technology certification firms and industrial technology verification(certification) companies showed that significant differences exist between groups for the program. These results suggest that more effective operation of the relevant policies may require policy enforcement in consideration of the level of security and will of each company in industrial technology, as much as the quantitative characteristics of the entity. This study is meaningful in providing the necessary policy directional basic information for the design and execution of more specific and effective industrial technology security policies by presenting empirical research results that domestic small and medium-sized enterprises are aware of about the government's industrial technology security policies.

• Journal of Digital Convergence
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• v.13 no.1
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• pp.205-213
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• 2015

Era of multi-channel digital multimedia on the Internet, cable, satellite and IPTV and the growth of new media such as terrestrial broadcast advertising with the poor rating has also dropped sharply. In this situation, terrestrial TV suggesting the introduction for total amount system appearing comments. In this study, the introduction of these intermediate advertising the public and professional awareness about the issue by comparing the introduction for total amount advertising feasibility was done in the purpose. The results were as follows. First, Studies on terrestrial TV suggesting the introduction of total amount system and public opinion about the differences in perception between experts is high. Second, Both the public and professionals about the total amount system preferred application stage were in favor of gradual for/limited permit cross-media. Third, the general population was higher than the positive response from experts about the benefits of the total amount system. Finally, the general public about the disadvantages of the total amount system they were more positive response than the experts. The introduction for total amount system validity of these data for future total amouny system to provide a basis for enforcement is expected to give.