• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.185.2-185.2
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• 2014

We have studied the atomic and electronic structure of graphene nanoribbons (GNRs) on a hexagonal boron nitride (h-BN) sheet with intercalated atoms using first-principles calculations. The h-BN sheet is an insulator with the band gap about 6 eV and then it may a good candidate as a supporting dielectric substrate for graphene-based nanodevices. Especially, the h-BN sheet has the similar bond structure as graphene with a slightly longer lattice constant. For the computation, we use the Vienna ab initio simulation package (VASP). The generalized gradient approximation (GGA) in the form of the PBE-type parameterization is employed. The ions are described via the projector augmented wave potentials, and the cutoff energy for the plane-wave basis is set to 400 eV. To include weak van der Waals (vdW) interactions, we adopt the Grimme's DFT-D2 vdW correction based on a semi-empirical GGA-type theory. Our calculations reveal that the localized states appear at the zigzag edge of the GNR on the h-BN sheet due to the flat band of the zigzag edge at the Fermi level and the localized states rapidly decay into the bulk. The open-edged graphene with a large corrugation allows some space between graphene and h-BN sheet. Therefore, atoms or molecules can be intercalated between them. We have considered various types of atoms for intercalation. The atoms are initially placed at the edge of the GNR or inserted in between GNR and h-BN sheet to find the effect of intercalated atoms on the atomic and electronic structure of graphene. We find that the impurity atoms at the edge of GNR are more stable than in between GNR and h-BN sheet for all cases considered. The nickel atom has the lowest energy difference of ~0.2 eV, which means that it is relatively easy to intercalate the Ni atom in this structure. Finally, the magnetic properties of intercalated atoms between GNR and h-BN sheet are investigated.

• Korean Institute of Interior Design Journal
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• v.22 no.1
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• pp.55-63
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• 2013

The main purpose of (the) performing arts is to efficiently communicate the themes and meanings which performances contain under limited time and place to the audience. Stage design should visually express play writer's scripts and director's interpretations of works, amid limitations. Although it is mostly designed metaphorically, in many cases, it is used only as a tool describing the background of performances but fails to effectively convey the true message of scenes to spectators. On the other hand, Bob Crowley has been recognized for his own design presentation skills to win 'Best Scenic Design of a Musical' of Tony Awards for six times and still exerts great influence on the musical and performing arts fields as a set designer. This study analyzes his reading of scripts and visual metaphor expressions, focusing on the musical, 'Aida' where the skills are mostly notable. To that end, we studied the concept of stage arts and theory of visual metaphoric expression to derive the features of his own technique in visual metaphor. Then, the features were applied to each scene of 'Aida' to see how they are displayed on stage. The result shows that Bob Crowley not only describes the background on stage, but also visualizes characters' personality and emotions in scenes. Such method of his expression is a proof to enhanced performance level by maximizing the atmosphere. Considering that a stage design should be based on the capacity of a designer to reinterpret the space with renewed viewpoints, visual metaphoric expression can serve as an effective tool to deliver clear messages to the audience under limited time and space, which is open to various methods of expressions.

• Resources Recycling
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• v.21 no.3
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• pp.65-73
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• 2012

There are several kinds of displays such as liquid crystal display (LCD), cathode ray tube (CRT), plasma display panel(PDP), light emitting diode (LED), organic light emitting diode (OLED), etc. Nowadays, recycling technologies of waste displays have been widely studied from economy and efficiency points of view. In this paper, patents and literature on the recycling technologies of the waste displays have been comprehensively analyzed. The search was limited to the open patents of USA (US), European Union (EU), Japan (JP), and Korea (KR) and SCI journals published from 1980 to 2011. Patents and journals were systematically compiled and collected using key-words search and filtered by pre-set filtering criteria. The trends of the patents and journals were thus analyzed according to the years, countries, companies, and technologies.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.12
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• pp.1914-1924
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• 2016

In this paper, considering virtualized Evolved Packet Core(vEPC) network for 5G mobile network, we propose architecture for supporting Service Function Chaining(SFC) in 5G mobile network. Using SFC in 5G network, dynamic path configuration and providing network services based on subscriber and traffic information. SFC technology provides logical ordered set of network functions and delivers packet through providing logical path over the physical network. Based on the perspective of 5G core network in distributed manner, we design hierarchical SFC architecture to manage SFC for global path including vEPC and SGi-LAN network, and internal path between virtualized network functions in each cloud. In this paper, we define architecture and call flow for establishing data path using SFC. Finally, we design testbed architecture for real implementation based on open source software.

• Journal of KIISE:Software and Applications
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• v.41 no.8
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• pp.557-568
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• 2014

Recently, software projects have been increasing and getting complex. Due to the large number of submitted bug reports, developers' workload increases. Generally in bug triage process, the triagers assign the bug report to fixer (developer) in order to resolve the bug. However, bug reports have been reassigned to other developers because fixers are not suitable. This is why the triagers did not correctly check and understand the bug report and decide the appropriate developers to fix the bug. This results in increase of developers' time and efforts in software maintenance. To resolve these problems, in this paper, we propose a novel method for developer recommendation based on topic model and social network. First, we build a basis of topic(s) from bug reports. Next, when a new bug report (test data set) comes, we select the most similar topic(s) and extract the participated developers from the topic(s). Finally, by applying social network, we analyze the developers' behavior (comment and commit activity) and recommend the appropriate developers. In this paper we compare our work with related studies through performance experiments on open source projects. The results show that our approach is more effective than other studies in bug triage.

• Journal of Conservation Science
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• v.5 no.1 s.5
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• pp.69-86
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• 1996

More than eighty thousands of wooden printing blocks of the Tripitaka Koreans are accommodated in the Changkyeonggak which consists of two open structured wooden buildings, Peoppojeon and Sudarajang. These blocks are virtually in pristine state even after three quarters of a millennium. The excellent preservation could be attributed to the careful preparation and meticulous finish of the blocks. But the meteorological environment or microclimate should be one of the key factors for the preservation. To keep the blocks intact as it is or at least do not accelerate the deterioration, we should study the blocks and its microclimatic environment supplied by the Changgyeonggak and the topology of the site. As a Part of this effort we designed a computerized meteorological data acquisition system, which can handle up to 4,096 sensors. A partial but operative installation of 16 temperature/humidity sensors was set up in the Peoppojeon. We hope to have a chance to install a full fledged system in the near future for the compilation of the fuller environmental data base.

• Journal of Crop Science and Biotechnology
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• v.10 no.3
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• pp.185-192
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• 2007

Near-infrared spectroscopy(NIRS) was used to develop a rapid and efficient method to determine lignan glucosides in intact seeds of sesame(Sesamum indicum L.) germplasm accessions in Korea. A total of 93 samples(about 2 g of intact seeds) were scanned in the reflectance mode of a scanning monochromator, and the reference values for lignan glucosides contents were measured by high performance liquid chromatography. Calibration equations for sesaminol triglucoside, sesaminol($1{\rightarrow}2$) diglucoside, sesamolinol diglucoside, sesaminol($1{\rightarrow}6$) diglucoside, and total amount of lignan glucosides were developed using modified partial least square regression with internal cross validation(n=63), which exhibited lower SECV(standard errors of cross-validation), higher $R^2$(coefficient of determination in calibration), and higher 1-VR(ratio of unexplained variance divided by variance) values. Prediction of an external validation set(n=30) showed a significant correlation between reference values and NIRS estimated values based on the SEP(standard error of prediction), $r^2$(coefficient of determination in prediction), and the ratio of standard deviation(SD) of reference data to SEP, as factors used to evaluate the accuracy of equations. The models for each glucoside content had relatively higher values of SD/SEP(C) and $r^2$(more than 2.0 and 0.80, respectively), thereby characterizing those equations as having good quantitative information, while those of sesaminol($1{\rightarrow}2$) diglucoside showing a minor quantity had the lowest SD/SEP(C) and $r^2$ values(1.7 and 0.74, respectively), indicating a poor correlation between reference values and NIRS estimated values. The results indicated that NIRS could be used to rapidly determine lignan glucosides content in sesame seeds in the breeding programs for high quality sesame varieties.

• The Plant Pathology Journal
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• v.20 no.1
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• pp.52-57
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• 2004

Sclerotinia sp. (isolate BWC98-105) causes stem blight and root rot in Leghum sp., and is presently being evaluated as a potential mycoherbicide for the control of Trifoliorium repens. Bioassays have shown that Sclerotinia sp. produces phytotoxic substance which is biologically active against T. repens. Two biologically active compounds, designated as compoundsI and II, were produced in vitro from the culture filtrate of BWC98-105 isolate Sclerotium sp. Compounds I and II were purified by means of liquid-liquid extraction and $C_{18}$ open column chromatography (300 ${\times}$ 30 mm, i.d). To determine the purity, the purified compounds were analyzed by RP-HPLC. The analytical RP-HPLC column was a TOSOH ODS-120T (150 ${\times}$ 4.6 mm i.d, Japan), of which the flow rate was set at 0.7 mL/min using the linear gradient solvent system initiated with 15 % methanol to 85 % methanol for 50 min with monitoring at 254 nm. Under these RP-HPLC conditions, compounds I and II eluted at 3.49 and 4.13 min, respectively. Compound II was found to be most potent and host specific. However, compound I had a unique antibiotic activity against phytopathogenic bacteria like bacterial leaf blight (Xanthomonas oryzae) on rice, where it played a less important role in producing toxicity on T. repens. No toxin activity was detected in the water fraction after partitioning with several organic solvents. However, toxin activity was detected in the ethyl acetate and butanol fractions. In the leaf bioassay using compound II, the disease first appeared within 4-5 h as water soaked rot, which subsequently developed into well-defined blight affecting the whole plant.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.2
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• pp.146-155
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• 2015

Objectives: The aims of this study were to set up benzene exposure matrices according to industry and process and to assess the risk of those occupational exposure to benzene. Methods: The benzene exposure matrices were assembled depending on industry and process, based on an exposure database provided by KOSHA(the Korean Occupational Safety and Health Agency), which was gathered from a workplace hazards evaluation program in Korea. These exposure matrices were assessed by Hallmark Risk Assessment tool. Results: The benzene was treated 412 industries sector(36%), 2,747 business places, and 471 industrial processes according to database. The arithmetic mean of past decade 8 hours time-weighted average of airborne benzene concentrations in the workplace was 0.10722 ppm. 1.07% of the total sample were greater than OEL, and 59.8% were showed less than the limit of detection. The highest risk values(Danger Value) were seen 36 industries including manufacture of general paints and similar product and 12 processes, such as other painting of manufacture of metal fabricated members. Exposure matrices based on employee exposure data base may provide exposure histories and can be used in epidemiological studies. Conclusions: It was found that more attentions should be paid to 36 among 412 industries and 12 of 471 processes, with a higher risk value.

• Archives of design research
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• v.16 no.1
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• pp.93-102
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• 2003

This thesis is a study for the standardization of the design of ginseng cultivating facility (also known as the sun off facility) for the improvement of farming environment. The core background of this study is to propose a basic study for introducing, for the first time, the modern ginseng cultivating facility that matches the position of korea as a main nation cultivating ginseng and to secure the production and quality value of Koryo Ginseng, which is a special world-level agricultural product of Korea, under the present WTO agricultural product open system. Right now, wood, rice straw, or vinyls, which are non-standardized or are for one-time use only are used. Therefore, as a concept of the design, 1 tried to revise the fact that these materials are being used to set up the facility repeatedly every year which is creating environmental pollution and wasting of our countries labor and resource. Concrete factors to be improved are as follows: First, standardization of the form and structure of mass production system; Second, introduction of new materials such as semi-permanent resin etc., for standardization of materials; 1 tried to make the above two factors into a shape based on a Korean image. As for the design, designed a standard unit model of the ginseng cultivation facility especially keeping in mind to design it so the facility can be freely connected and assembled according to the size and shape of the cultivation area.