• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.4
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• pp.579-586
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• 2018

Short-term prediction of travel speed has been widely studied using data-driven non-parametric techniques. There is, however, a lack of research on the prediction aimed at urban areas due to their complex dynamics stemming from traffic signals and intersections. The purpose of this study is to develop a hybrid approach combining ensemble empirical mode decomposition (EEMD) and artificial neural network (ANN) for predicting urban travel speed. The EEMD decomposes the time-series data of travel speed into intrinsic mode functions (IMFs) and residue. The decomposed IMFs represent local characteristics of time-scale components and they are predicted using an ANN, respectively. The IMFs can be predicted more accurately than their original travel speed since they mitigate the complexity of the original data such as non-linearity, non-stationarity, and oscillation. The predicted IMFs are summed up to represent the predicted travel speed. To evaluate the proposed method, the travel speed data from the dedicated short range communication (DSRC) in Daegu City are used. Performance evaluations are conducted targeting on the links that are particularly hard to predict. The results show the developed model has the mean absolute error rate of 10.41% in the normal condition and 25.35% in the break down for the 15-min-ahead prediction, respectively, and it outperforms the simple ANN model. The developed model contributes to the provision of the reliable traffic information in urban transportation management systems.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.135-135
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• 2015

Tubes are of extreme importance in industries as for fluid channels or wave guides. Furthermore, some weapon systems such as cannons use the tubes as gun barrels. To increase the service life of such tubes, a protective coating must be applied to the tubes' inner surface. However, the coating methods applicable to the inner surface of the tubes are very limited due to the geometrical restriction. A small-diameter cylindrical magnetron sputtering gun can be used to deposit coating layers on the inner surface of the large-bore tubes. However, for small-bore tubes with the inner diameter of one inch (~25 mm), the magnetron sputtering method can hardly be accommodated due to the space limitation for permanent magnet assembly. In this study, a new approach to coat the inner surface of small-bore tubes with the inside diameter of one inch was developed. Instead of using permanent magnets for magnetron operation, an external electro-magnet assembly was adopted around the tube to confine the plasma and to sustain the discharge. The electro-magnet was operated in pulse mode to provide the strong axial magnetic field for the magnetron operation, which was synchronized with the negative high-voltage pulse applied to the water-cooled coaxial sputtering target installed inside the tube. By moving the electro-magnet assembly along the tube's axial direction, the inner surface of the tube could be uniformly coated. The inner-surface coating system in this study used the tube itself as the vacuum chamber. The SS-304 tube's inner diameter was 22 mm and the length was ~1 m. A water-cooled Cu tube (sputtering target) of the outer diameter of 12 mm was installed inside of the SS tube (substrate) at the axial position. The 50 mm-long electro-magnet assembly was fed by a current pulse of 250 A at the frequency and pulse width of 100 Hz and 100 usec, respectively. The calculated axial magnetic field strength at the center was ~0.6 Tesla. The central Cu tube was synchronously driven by a HiPIMS power supply at the same frequency of 100 Hz as the electro-magnet and the applied pulse voltage was -1200 V with a pulse width of 500 usec. At 150 mTorr of Ar pressure, the Cu deposition rate of ~10 nm/min could be obtained. In this talk, a new method to sputter coat the inner surface of small-bore tubes would be presented and discussed, which might have broad industrial and military application areas.

• Proceedings of the Korea Contents Association Conference
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• 2006.11a
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• pp.652-656
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• 2006

Bibliographic information retrieval systems require bibliographic data such as authors, organizations, source of publication to be uniquely identified using keys. In particular, when authors are represented simply as their names, users bear the burden of manually discriminating different users of the same name. Previous approaches to resolving the problem of same-name authors rely on bibliographic data such as co-author information, titles of articles, etc. However, these methods cannot handle the case of single author articles, or the case when articles do not have common terms in their titles. To complement the previous methods, this study introduces a classification-based approach using similarity between full-text of articles. Experiments using recent domestic proceedings showed that the proposed method has the potential to supplement the previous meta-data based approaches.

• Genomics & Informatics
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• v.10 no.1
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• pp.1-8
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• 2012

Recently, the technologies of DNA sequence variation and gene expression profiling have been used widely as approaches in the expertise of genome biology and genetics. The application to genome study has been particularly developed with the introduction of the nextgeneration DNA sequencer (NGS) Roche/454 and Illumina/ Solexa systems, along with bioinformation analysis technologies of whole-genome $de$ $novo$ assembly, expression profiling, DNA variation discovery, and genotyping. Both massive whole-genome shotgun paired-end sequencing and mate paired-end sequencing data are important steps for constructing $de$ $novo$ assembly of novel genome sequencing data. It is necessary to have DNA sequence information from a multiplatform NGS with at least $2{\times}$ and $30{\times}$ depth sequence of genome coverage using Roche/454 and Illumina/Solexa, respectively, for effective an way of de novo assembly. Massive shortlength reading data from the Illumina/Solexa system is enough to discover DNA variation, resulting in reducing the cost of DNA sequencing. Whole-genome expression profile data are useful to approach genome system biology with quantification of expressed RNAs from a wholegenome transcriptome, depending on the tissue samples. The hybrid mRNA sequences from Rohce/454 and Illumina/Solexa are more powerful to find novel genes through $de$ $novo$ assembly in any whole-genome sequenced species. The $20{\times}$ and $50{\times}$ coverage of the estimated transcriptome sequences using Roche/454 and Illumina/Solexa, respectively, is effective to create novel expressed reference sequences. However, only an average $30{\times}$ coverage of a transcriptome with short read sequences of Illumina/Solexa is enough to check expression quantification, compared to the reference expressed sequence tag sequence.

• Korean Journal of Social Welfare
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• v.60 no.1
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• pp.53-76
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• 2008

The aim of this study is to understand the ethical struggles of Child Protective Service(CPS) social workers and to indicate some implications for future studies by conducting research focusing on their ethical dilemmas and decision-making. This study used qualitative methods, in particular the phenomenological approach and 14 in-depth semi-structured interviews with CPS social workers, and were conducted and analyzed using the procedures of Colaizzi(1978). This study looks at the following research questions: 1) What kind of ethical dilemmas do CPS social workers encounter? This means what ethical dilemmas do they directly or indirectly encounter because of policy or system inadequacies and huge caseloads. 2) How do the CPS social workers make decisions when they are faced with ethical dilemmas? Making the best decisions with all of their responsibilities and burdens is the focus of this question. This study suggests the following discussions: First, efforts to emphasize 'ethics' at CPS are needed. Second, proper policies and systems based on the Korean situation are needed so that CPS social workers won't have to face 'needless' ethical dilemmas. Third, an index of ethical problems or ethical codes is necessary because principles are important to those social workers who face ethical dilemmas. Fourth, an ethical committee that protects the CPS social workers by supporting their decisions and being responsible for them is needed. Last, a debriefing system that reduces a CPS social worker's psychological trauma caused by ethical dilemmas should be available.

• Journal of Environmental Policy
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• v.10 no.3
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• pp.93-117
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• 2011

The double dividend hypothesis of environmental taxes has been a very widely debated research topic since its introduction in the mid-80s. Unlike the second generation studies, which stated that the double dividend environmental taxes were impossible to realize, the third generation researchers of today are focused on assumptions or conditions that make the hypothesis viable. The third generation studies state that the double dividend hypothesis is possible through functional form assumptions, such as the characteristics of taxes levied on polluting goods and the overall tax efficiency of the initial tax systems. The most notable, however, is the fact that the working mechanisms of third generation studies, upon closer inspection, give homogeneous effect on the labor markets, although at first glance the third generation studies take seemingly unrelated approaches. This thesis stems from such idea, and it attempts to analyze the effects of environmental taxes on the labor market. After a thorough analysis, the results match the intuition, as the viability of the double dividend hypothesis of environmental taxes largely depends on the effects that policy changes generate on the labor market. In order for the hypothesis to be plausible, environmental tax policies have to increase the labor supply.

• Journal of Environmental Impact Assessment
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• v.17 no.2
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• pp.113-124
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• 2008

A worldwide trend of permitting system for industrial installation to achieve a high level of protection of the environment has been moved from single media to multimedia in approach. The Council of the European Community issued the Directive 96/61/EC, the IPPC Directive, concerning integrated pollution prevention and control in 1996. The IPPC Directive is one of the most ambitious legal measures that the European Union (EU) has initiated with a view to applying the prevention principle for industrial activities. The IPPC aims to achieve the integrated prevention and reduction of environmental pollution emitted by those industrial installations with a higher potential of emissions to the environment. Organization for Economic Cooperation and Development (OECD) recommended on Environmental Performance Reviews of Korea in 2006 that IPPC permitting concept should be considered for large stationary sources at the national and regional levels. Any Korean law doesn't provide for integrated pollution control with a single process covering all pollution from economic activities. However, one exception might be the "environmentally-friendly companies" certification scheme, introduced in 1995, in which participants agree to meet targets beyond the legal emission limit values in exchange for government technical and financial support to operate environmental management systems. The other exception might be Environmental impact assessment (EIA) of projects, in 1977, which has been strengthened and reinforced to be more preventive through development of the prior environmental review system (PERS) in 1999. The aim of this work is to introduce the contents of IPPC Directive at the viewpoint of Korea policy and to survey the integrated approaching concept of Environmentally-Friendly Companies (EFC) Certification Scheme and EIA policy of Korea. The study will be helpful in the future to prepare the infrastructure of integrated permitting system and to enforce the integrated permit which the authorities of local government issues on industrial activities. It can be said that the data calculated through both EFC Certification Scheme and EIA will be discussed as worthful information to determine Korean BAT reference notes for integrated permitting process.

• Science of Emotion and Sensibility
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• v.13 no.3
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• pp.501-510
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• 2010

The knowledge base on emotional information is one of the key elements in the implementation of emotion retrieval systems for contents design of Mobile devices. This study proposed a new approach to the knowledge base implementation by automatically extracting color components from full-color images. In this study, the validity of the proposed method was empirically tested. Database was developed using 100 interior images as visual stimuli and a total of 48 subjects participated in the experiment. In order to test the reliability of the proposed 'emotional information knowledge base', firstly 'recall ratio' that refers to frequencies of correct images from the retrieved images was derived. Secondly, correlation Analysis was performed to compare the ratings by the subjects to what the system calculated. Finally, the rating comparison was used to run a paired-sample t-test. The analysis demonstrated satisfactory recall ration of 62.1%. Also, a significant positive correlation (p<.01) was observed from all the emotion keywords. The paired Sample t-test found that all the emotion keywords except "casual" retrieved the images in the order from more relevant to less relevant images and the difference was statistically significant (t(9)=5.528, p<.05). Findings of this study support that the proposed 'emotional information knowledge base' established only with color information automatically extracted from images can be effectively used for such visual stimuli search tasks as commercial interior images.

• The KIPS Transactions:PartC
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• v.15C no.5
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• pp.351-358
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• 2008

Recently, as network flooding attacks such as DoS/DDoS and Internet Worm have posed devastating threats to network services, rapid detection and proper response mechanisms are the major concern for secure and reliable network services. However, most of the current Intrusion Detection Systems(IDSs) focus on detail analysis of packet data, which results in late detection and a high system burden to cope with high-speed network environment. In this paper we propose a lightweight and fast detection mechanism for traffic flooding attacks. Firstly, we use SNMP MIB statistical data gathered from SNMP agents, instead of raw packet data from network links. Secondly, we use a machine learning approach based on a Support Vector Machine(SVM) for attack classification. Using MIB and SVM, we achieved fast detection with high accuracy, the minimization of the system burden, and extendibility for system deployment. The proposed mechanism is constructed in a hierarchical structure, which first distinguishes attack traffic from normal traffic and then determines the type of attacks in detail. Using MIB data sets collected from real experiments involving a DDoS attack, we validate the possibility of our approaches. It is shown that network attacks are detected with high efficiency, and classified with low false alarms.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.1
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• pp.39-48
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• 2005

According to traditional 2D animation techniques, anticipation makes an animation much convincing and expressive. We present an automatic method for inserting anticipation effects to an existing facial animation. Our approach assumes that an anticipatory facial expression can be found within an existing facial animation if it is long enough. Vertices of the face model are classified into a set of components using principal components analysis directly from a given hey-framed and/or motion -captured facial animation data. The vortices in a single component will have similar directions of motion in the animation. For each component, the animation is examined to find an anticipation effect for the given facial expression. One of those anticipation effects is selected as the best anticipation effect, which preserves the topology of the face model. The best anticipation effect is automatically blended with the original facial animation while preserving the continuity and the entire duration of the animation. We show experimental results for given motion-captured and key-framed facial animations. This paper deals with a part of broad subject an application of the principles of traditional 2D animation techniques to 3D animation. We show how to incorporate anticipation into 3D facial animation. Animators can produce 3D facial animation with anticipation simply by selecting the facial expression in the animation.