• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.171.2-171.2
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• 2016

The 2-dimensiona electron gas (2DEG) layers have opened tremendous interests in the heterooxide interfaces formed between two insulating materials, especially between LaAlO3 and $SrTiO_3$. The 2DEG layers exhibit extremely high mobility and carrier concentrations along with metallic transport phenomena unlike the constituent oxide materials, i.e., $LaAlO_3$ and $SrTiO_3$. The current work inserted artificially the interfacial layer, $Sr_xCa_{1-x}TiO_3$ between $LaAlO_3$ and $SrTiO_3$, with the aim to controlling the 2-dimensional transports. The insertion of the additional materials affect significantly their corresponding electrical transports. Such features have been probed using DC and AC-based characterizations. In particular, impedance spectroscopy was employed as an AC-based characterization tool. Frequency-dependent impedance spectroscopy have been widely applied to a number of electroceramic materials, such as varistors, MLCCs, solid electrolytes, etc. Impedance spectroscopy provides powerful information on the materials system: i) the simultaneous measurement of conductivity and dielectric constants, ii) systematic identification of electrical origins among bulk-, grain boundary-, and electrode-based responses, and iii) the numerical estimation on the uniformity of the electrical origins. Impedance spectroscopy was applied to the $LaAlO_3/Sr_xCa_{1-x}TiO_3/SrTiO_3$ system, in order to understand the 2-dimensional transports in terms of the interfacial design concepts. The 2-dimensional conduction behavior system is analyzed with special emphasis on the underlying mechanisms. Such approach is discussed towards rational optimization of the 2-dimensional nanoelectronic devices.

• Journal of the Korea Convergence Society
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• v.7 no.6
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• pp.13-21
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• 2016

In this paper we are trying to explain the effect of temperature on polymer membrane exchange water electrolysis (PEMWE) and polymer membrane exchange fuel cell (PEMFC) simultaneously. A comprehensive studying approach is proposed and applied to a 50Watt PEM fuel cell system in the laboratory. The monitoring process is carried out through wireless LoRa node and gateway network concept. In this experiment, temperature sensor measure the temperature level of electrolyzer, fuel cell stack and $H_2$ storage tank and transmitted the measured value of data to the management control unit (MCU) through the individual node and gateway of each PEMWE and PEMFC. In MCU we can monitor the temperature and its effect on the performance of the fuel cell system and control it to keep the lower heating value to increase the efficiency of the fuel cell system. And we also proposed a mathematical model and operation algorithm for PEMWE and PEMFC. In this model, PEMWE gives higher efficiency at lower heating level where as PEMFC gives higher efficiency at higher heating value. In order to increase the performance of the fuel cell system, we are going to monitor, communicate and control the temperature and pressure of PEMWE and PEMFC by installing these systems in a building of university which is located in the southern part of Korea.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.525-530
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• 2017

Weaning is the most stressful event for nursery pigs because they are moved from familiar to unfamiliar environments. In addition, weaned pigs have immature digestive and immune systems. This situation makes weaned pigs susceptible to diseases and makes the absorption of nutrients from diets difficult. A feed approach, such as dietary enzyme supplementation, can be considered a solution. This study investigated the effects of dietary enzyme cocktail on diarrhea and immune responses of weaned pigs. A total 36 weaned pigs ($5.92{\pm}0.48kg\;BW$; 28 d old) were randomly allotted to 2 dietary treatments (3 pigs/pen, 6 replicates/treatment) in a randomized complete block design. The dietary treatments were a typical diet based on corn and soybean meal (CON) and CON with 0.05% enzyme cocktail (Cocktail; combination of xylanase, ${\alpha}-amylase$, protease, ${\beta}-glucanase$, and pectinase). Pigs were fed their respective diets for 6 wk. Incidence of diarrhea, packed cell volume (PCV), white blood cells (WBC) count, and immunoglobulin content were measured. A significantly lower incidence of diarrhea (p < 0.05) was observed in the Cocktail group as compared with the CON group. The Cocktail group also showed a decreased PCV (p < 0.1) on d 3 after weaning than the CON group. However, no differences were observed for number of WBC and contents of immunoglobulin G, M, and A between the Cocktail and CON groups. Consequently, inclusion of an enzyme cocktail in diets for weaned pigs had a positive influence on gut health by reducing the incidence of diarrhea in the present study.

• Cartoon and Animation Studies
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• s.37
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• pp.143-158
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• 2014

In the modeling processes of 3D computer animation, methods to build optimal work conditions to realize real forms for more efficient works have been advanced. Digital sculpting software, published in 1999, ZBrush has been positioned as an essential factor in character model work requiring of realistic descriptions through different manufacturing methods from previous modeling work processes and easy shape realization. Their functional areas are expanding. So, in this production case paper, as a method to product more optimized animation character models, the efficiency of production method linking digital sculpting software (Z-Brush) and animation production software (Maya) was deliberated and its consequences and implications are suggested. To this end, first the technical features of polygon modeling and Retopology were reviewed. Second, based on it, the efficiency of animation character modeling work processes through step linking ZBrush and Maya suggested in this paper was analyzed. Third, based on the features drawn before, in order to prove the hypothesis on modeling optimization method suggested in this paper, the production process of character Dumvee from a short animation film, 'Cula & Mina' was analyzed as an example. Through this study, it was found that technical approach easiness and high level of completion could be realized through two software linked work processes. This study is considered to be a reference for optimizing production process of related industries or modeling-related classes by deliberating different modeling process linked systems.

• Cartoon and Animation Studies
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• s.37
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• pp.221-245
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• 2014

With the success of the world's first 3D computer animated film, "Toy Story" in 1995, industrial development of 3D computer animation gained considerable momentum. Consequently, various 3D animations for TV were produced; in addition, high quality 3D computer animation games became common. To save a large amount of 3D animation production time and cost, technological development has been conducted actively, in accordance with the expansion of industrial demand in this field. Further, compared with the traditional approach of producing animations through hand-drawings, the efficiency of producing 3D computer animations is infinitely greater. In this study, an experiment and a comparative analysis of markerless motion capture systems for facial expression animation has been conducted that aims to improve the efficiency of 3D computer animation production. Faceware system, which is a product of Image Metrics, provides sophisticated production tools despite the complexity of motion capture recognition and application process. Faceshift system, which is a product of same-named Faceshift, though relatively less sophisticated, provides applications for rapid real-time motion recognition. It is hoped that the results of the comparative analysis presented in this paper become baseline data for selecting the appropriate motion capture and key frame animation method for the most efficient production of facial expression animation in accordance with production time and cost, and the degree of sophistication and media in use, when creating animation.

• 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.