• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.1
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• pp.89-99
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• 2018

The number of traffic accidents in Korea has been increasing since 2014. In most school zones, safety signs are installed to prevent children's traffic accidents. However, it has been known that the effects of those signs are not significant. A variable message sign(VMS), one of the components of Intelligent Transport System(ITS), has emerged as an alternative method. Therefore, this study examines relative effects of two different VMS messages(Timely vs. Continuous) on vehicle speed. Experiments were conducted in two school zones. 6,676 vehicles were measured for speed limit compliance. A counterbalanced multiple baseline design was adopted. The results showed that both types of message are effective in reducing the speed of vehicle. Specifically, A timely message was more effective in slowing down vehicle speed and improving speed limit compliance than a continuous message. The present study suggested that a VMS with human factors can be effective.

• Journal of Digital Contents Society
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• v.16 no.2
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• pp.207-218
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• 2015

This study is to design and implement Smartphone application by applying the principles and processes of narrative therapy for the participants. The application is able for participants to fight out of the difficulty in question centered on the issue, and to be able to find a positive new stories to be evolving the story of their lives as well. Therefore, using the application will help them to live a healthier life out of the problems. As a way of currying the wounded heart of the youth, narrative therapy techniques were applied to Smartphone appliances accustomed to the youth. The youths' wounded minds will not only be easily cured but also can be a important factor in determining the direction of life. In this study, narrative flow was structured into four stages; relationships, externalization, creating new stories and strengthening the new story bsed on Doll & Doll' theory. Based on them, the Smartphone application for curing the wounded heart was designed and developed by utilizing narrative therapy techniques. The application was tested by 30 University students in Jeonbuk province in Korea and the results showed that they were satisfied with the application with relation to improving their heart health.

• Structural Monitoring and Maintenance
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• v.2 no.1
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• pp.77-93
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• 2015

The idea of using measured dynamic characteristics for damage detection is attractive because it allows for a global evaluation of the structural health and condition. However, vibration-based damage detection for complex structures such as long-span cable-supported bridges still remains a challenge. As a suspension or cable-stayed bridge involves in general thousands of structural components, the conventional damage detection methods based on model updating and/or parameter identification might result in ill-conditioning and non-uniqueness in the solution of inverse problems. Alternatively, methods that utilize, to the utmost extent, information from forward problems and avoid direct solution to inverse problems would be more suitable for vibration-based damage detection of long-span cable-supported bridges. The auto-associative neural network (ANN) technique and the probabilistic neural network (PNN) technique, that both eschew inverse problems, have been proposed for identifying and locating damage in suspension and cable-stayed bridges. Without the help of a structural model, ANNs with appropriate configuration can be trained using only the measured modal frequencies from healthy structure under varying environmental conditions, and a new set of modal frequency data acquired from an unknown state of the structure is then fed into the trained ANNs for damage presence identification. With the help of a structural model, PNNs can be configured using the relative changes of modal frequencies before and after damage by assuming damage at different locations, and then the measured modal frequencies from the structure can be presented to locate the damage. However, such formulated ANNs and PNNs may still be incompetent to identify damage occurring at the deck members of a cable-supported bridge because of very low modal sensitivity to the damage. The present study endeavors to enhance the damage identification capability of ANNs and PNNs when being applied for identification of damage incurred at deck members. Effort is first made to construct combined modal parameters which are synthesized from measured modal frequencies and modal shape components to train ANNs for damage alarming. With the purpose of improving identification accuracy, effort is then made to configure PNNs for damage localization by adapting the smoothing parameter in the Bayesian classifier to different values for different pattern classes. The performance of the ANNs with their input being modal frequencies and the combined modal parameters respectively and the PNNs with constant and adaptive smoothing parameters respectively is evaluated through simulation studies of identifying damage inflicted on different deck members of the double-deck suspension Tsing Ma Bridge.

• Journal of the Korean Geotechnical Society
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• v.33 no.3
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• pp.29-36
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• 2017

It has been known that rockbolt is one of important supports improving the support capacity with shotcrete in NATM tunnel. Also, it is necessary for the inclined system bolting to enhance the efficiency of installation in case of a narrow space such as cross passage and enlargement tunnel. However, there is no profound technical study for the effect of inclined rockbolt of systematic installation on the support mechanism and ground behaviour in NATM tunnel. In this study, the effects of the length and installation angle of rockbolt on the characteristics of support and ground reinforcement were analyzed by using 3D finite element numerical study. Through the numerical results for the parametric modelling of inclined rockbolt, the characteristics of mechanical behaviors between the axial force of rockbolt and the effect of ground reinforcement in regard to the various factors of the length and installation angle of rockbolt were verified and reviewed thoroughly. Also, it was shown that the installation angle of rockbolt for enhancing the arching effect in NATM tunnel was $45^{\circ}$, and the difference of the reinforcing effect for support between the installation angles of $75^{\circ}$ and $90^{\circ}$ was insignificant. The additional numerical studies for various condition would be carried out for practical design guideline of inclined rockbolt.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.27 no.1
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• pp.5-25
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• 2016

This study attempts to suggest an improvement plan of the currently prescribed record classification standard table as the guidance to select and assess the public records of local governments. For this purpose, this study utilized the methodologies of literature review, survey, and experts' assessments. It investigated the current situation on unit tasks and preservation periods targeting major functions of 'construction and architecture' in the record management standard table in the 9 provinces, and it also deduced the characteristics and problems of unit task and preservation period by comparing and analyzing the unit task and preservation period utilized in more than 3 provinces. Based on the results from the analysis on the current situation and comparison, this study deduced the new unit tasks and preservation periods. And the evaluation targeting practitioners and expertise was conducted, and then the revised design plan was finally presented 4 medium- function items, 18 small - function items operated in more than 4 provinces, 47 unit task items, which led to the total 69 items. This study can be utilized as a guidance for establishing the record management standard table based on the uniqueness and originality of public record of local governments and the task function and organization of institutions in the future.

• Journal of the Korea Institute of Building Construction
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• v.11 no.2
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• pp.145-153
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• 2011

Since the early 1990s, Korean construction companies have strived to evolve into global Engineering Construction (EC) companies. However, such efforts have been unsuccessful, partly due to a lack of clear objectives and a misunderstanding of the direction that needed to be taken for such a change. A better understanding is required with respect to the need to transform into an EC company in the context of the rapidly changing global construction environment. This research investigates major EC companies from around the world, and assesses the status of domestic companies' efforts for EC transition. The results of these investigations revealed that domestic firms need to better prioritize their strengths for different markets, i.e., decide whether to implement directly, outsource or limit to process management. In addition, the investigations showed that the global market is shifting from monolithic projects to more complex projects. Such projects require firms with the ability to develop and implement high front-end investment strategies, planning capabilities, and pre-design management skills. Accordingly, we recommend that firms differentiate themselves by developing such a skill set required for specific products.

• Journal of the Korean Electrochemical Society
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• v.12 no.3
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• pp.203-218
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• 2009

The development of lithium-ion battery (LIB) technologies and their application in the field of large-scale power sources, such as electric vehicles (EVs), hybrid EVs, and plug-in EVs require enhanced reliability and superior safety. The main components of LIBs should withstand to the inevitable heating of batteries during high current flow. Carbonate solvents that contribute to the dissociation of lithium salts are volatile and potentially combustible and can lead to the thermal runaway of batteries at any abuse conditions. Recently, an interest in nonflammable materials is greatly growing as a means for improving battery safety. In this review paper, novel approaches are described for designing highly safe electrolytes in detail. Non-flammability of liquid electrolytes and battery safety can be achieved by replacing flammable organic solvents with thermally resistive materials such as flame-retardants, fluorinated organic solvents, and ionic liquids.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.2
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• pp.42-52
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• 2008

This paper categorized the functions of and investigated the characteristics of planting in Pyeonghwa Park near the Seoul World Cup Stadium as a preliminary study for improving tree planting in the park. The functions of planting were deduced based on related theoretical studies and an analysis of the intention of design and environmental factors. The characteristics of planting were analyzed after drawing the distribution and stratification of dominant planting species and setting samples by function. The functions of planting were classified into natural landscape planting, buffer planting, and shade planting. For dominant planting species, pine trees and elm-like trees have been widely observed while various species in addition to pine trees in natural landscape planting areas have been introduced in terms of the function of planting. These trees that were randomly planted before the park was developed have been obstacles in the formation of natural landscapes. For buffer planting and topographical correction, tall trees were planted. However, it seems that comprehensive complementary measures should be taken on the under-story planting.

• Journal of Navigation and Port Research
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• v.42 no.3
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• pp.217-226
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• 2018

International major container terminals are trying to expand automation facilities in order to dominate the competition and grow as central harbors. Recently, system design and development were put underway to fully integrate automation systems in container terminals. This is because it can focus on improving the efficiency of the yard operations in container terminals and facilitates integration with other container terminal operation processes. Automation in the container terminal business today is essential to better serve customers and improve profitability. Real-time position and status of container handling equipment (CHE) have been required for more efficient terminal operations and consequently higher productivity. This study examined the real-time location and status of the container terminal automation equipment using DGPS in container terminals, and reviewed the components and functions of the container terminal automation yard equipment systems that developed, applied, and operated the automation systems. In addition, this study compared the existing yard system and the automation yard system and presented application methods. Also, the results revealed that the productivity of the container terminal and the efficiency of the transportation equipment can be further increased when the optimal yard automation transportation equipment system is used to efficiently operate the transportation equipment, which is the core equipment of the container terminal.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.1B
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• pp.42-48
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• 2002

In broadband wireless networks, the effective meeting of the QoS guarantees may strongly depend on the Contention Resolution Algorithm used in the uplink contention period. The time it takes a station to transmit a successful request to the base station, or request delay, must be kept low even during periods of high contention. If a request suffers many collisions, it cannot rely on the preemptive scheduler to receive low access delays. However, the conventional collision resolution algorithm has a problem that all collided stations are treated equally regardless of their delay from previous contention periods. Some requests may have very long request delay caused by continuous collisions. In this paper, we propose an adaptive collision resolution algorithm for fast random access in broadband wireless networks. The design goal is to provide quick access to the request with a high number of collisions. To do this, the proposed algorithm separates the whole contention region into multiple sub regions and permits access through each sub region only to the requests with equal number of collisions. The sub region is adaptively created according to the feedback information of previous random access. By simulation, the proposed algorithm can improve the performance in terms of throughput, random delay and complementary distribution of random delay by its ability to isolate higher priorities from lower ones. We can notice the algorithm provides efficiency and random access delay in random access environment.