• 대한예방의학회:학술대회논문집
• /
• 2002.10a
• /
• pp.334-335
• /
• 2002

• Journal of Mechanical Science and Technology
• /
• v.17 no.5
• /
• pp.691-697
• /
• 2003

Extensive researches have been carried out on machine tool chatter to obtain assessment procedure and improvement measures. In this study, chatter limit is predicted on a newly fabricated universal machining center by the combination of structural dynamic characteristics and cutting mechanics. We showed the unstable cutting conditions, and from them we could plot the unstable borderlines. From the chatter simulations we could say that the newly built universal machining center can be well used in the finishing machining of steel as other common machine tools.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.11b
• /
• pp.238-242
• /
• 2001

In this paper, the current-voltage characteristics of a 4H-SiC MESFET is simulated by using the Atlas Simulation tool. we are able to use the simulator to extract more information about the new material 4H-SiC, including the mobility, velocity-field Curve and the Schottky barrier height. We have enabled and used the new simulator to investigate breakdown Voltage and thus predict operation limitiations of 4H-SiC device. Modeling results indicate that the Breakdown Voltage is 197 V and Current is 100 mA

• Journal of The Korean Association of Information Education
• /
• v.1 no.2
• /
• pp.16-34
• /
• 1997

This paper describes a method of building a intelligent learning system consisting of a authoring tool, in the area of language education, and a Intelligent Tutoring System(ITS) to study English. This tool is different from commerical authoring tools, as a tool that has capabilities as a component of an ITS and this ITS is efficient to retrieve the lesson plan from the plan memory than to generate it whenever an instructinoal goal is selected. the results of this research could be used either by a developer of the other area of ITS, or by a human teacher as a curriculum in the actual class.

• Management & Information Systems Review
• /
• v.36 no.3
• /
• pp.131-150
• /
• 2017

The purpose of this study is to observe the spread pattern of open source software (OSS) while establishing relations with surrounding actors during its operation period. In order to investigate the change pattern of participants in the OSS, we use a netnography on the basis of online data, which can trace the change patterns of the OSS depending on the passage of time. For this, the cases of three OSSs (e.g. jQuery, MooTools, and YUI), which are JavaScript frameworks, were compared, and the corresponding data were collected from the open application programming interface (API) of GitHub as well as blog and web searches. This research utilizes the translation process of the actor-network theory to categorize the stages of the change patterns on the OSS translation process. In the project commencement stage, we identified the type of three different OSS-related actors and defined associated relationships among them. The period, when a master commences a project at first, is refined through the course for the maintenance of source codes with persons concerned (i.e. project growth stage). Thereafter, the period when the users have gone through the observation and learning period by being exposed to promotion activities and codes usage respectively, and becoming to active participants, is regarded as the 'leap of participants' stage. Our results emphasize the importance of promotion processes in participants' selection of the OSS for participation and confirm the crowding-out effect that the rapid speed of OSS development retarded the emergence of participants.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.28 no.2
• /
• pp.397-405
• /
• 2018

Blacklist-based tools are most commonly used to effectively detect suspected malicious processes. The blacklist-based tool compares the malicious code extracted from the existing malicious code with the malicious code. Therefore, it is most effective to detect known malicious codes, but there is a limit to detecting malicious code variants. In order to solve this problem, the necessity of a white list-based tool, which is the opposite of black list, has emerged. Whitelist-based tools do not extract features of malicious code processes, but rather collect reliable processes and verify that the process that checks them is a trusted process. In other words, if malicious code is created using a new vulnerability or if variant malicious code appears, it is not in the list of trusted processes, so it can effectively detect malicious code. In this paper, we propose a method for effectively building a whitelist through research that collects reliable processes in the macOS operating system.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.113-113
• /
• 2017

Downy mildew (DM), caused by several species in the Peronosclerospora and Scleropthora genera, is a major maize (Zea mays L.) disease in tropical or subtropical regions. DM is an obligate parasite species in the higher plants and spreads by oospores, wind, and mycelium in seed surface, soil, and living hosts. Owing to its geographical distribution and destructive yield reduction, DM is one of the most severe maize diseases among the maize pathogens. Positional cloning in combination with phenotyping is a general approach to identify disease resistant gene candidates in plants; however, it requires several time-consuming steps including population or fine mapping. Therefore, in the present study, we suggest a new combination strategy to improve the identification of disease resistant gene candidates. Downy mildew (DM) resistant maize was selected from five cultivars using the spreader row technique. Positional cloning and bioinformatics tools identified the DM resistant QTL marker (bnlg1702) and 47 protein coding genes annotations. Eventually, 5 DM resistant gene candidates, including bZIP34, Bak1, and Ppr, were identified by quantitative RT-PCR without fine mapping of the bnlg1702 locus. Specifically, we provided DM resistant gene candidates with our new strategy, including field selection by the spreader row technique without population preparation, the DM resistance region identification by positional cloning using bioinformatics tools, and expression level profiling by quantitative RT-PCR without fine mapping. As whole genome information is available for other crops, we propose applying our novel protocol to other crops or for other diseases with suitable adjustment.

• Journal of Information Technology Services
• /
• v.17 no.3
• /
• pp.171-189
• /
• 2018

To remove software defects and improve performance of software, many developers perform code inspections and use static analysis tools. A code inspection is an activity that is performed manually to detect software defects in the developed source. However, there is no clear criterion which source codes are inspected. A static analysis tool can automatically detect software defects by analyzing the source codes without running the source codes. However, it has disadvantage that analyzes only the codes in the functions without analyzing the relations among source functions. The functions in the source codes are interconnected and formed a social network. Functions that occupy critical locations in a network can be important enough to affect the overall quality. Whereas, a static analysis tool merely suggests which functions were called several times. In this study, the core functions will be elicited by using social network analysis and DEA (Data Envelopment Analysis) for CUBRID open database sources. In addition, we will suggest clear criteria for selecting the target sources for code inspection and will suggest ways to find core functions to minimize defects and improve performance.

• Korean Journal of Acupuncture
• /
• v.25 no.2
• /
• pp.107-114
• /
• 2008

Objectives : Accurate location of acupoints is a prerequisite for both practice and research into acupoint specificity. Given that accurate location of acupoints is one of the most important issues in meridianology education, this study aimed at evaluating if the elastic ruler method for locating acupoints is suitable for meridianology practice class. Methods : Fifty-six students who took meridianology practice class participated in the experiment. Firstly, they were asked to locate PC6, CV12 and ST36 without any assisting tools and the distance between standard acupoint and their acupoint location was measured. Secondly, they were again asked to locate the same points this time with an elastic ruler. Then the first and second measurements were compared using a paired t-test. Results : Analysis of the results found using an elastic ruler significantly improved the difference between the student's acupoint location and the standard acupoint: there was a significant difference between 1st and 2nd measurements for PC6 (1.87${\pm}$0.29mm vs. 1.28${\pm}$0.19mm, P=0.037) and for ST36 (2.70${\pm}$0.22mm vs. 1.38${\pm}$0.15mm, P<0.0001). Conclusions : Using an elastic ruler as an assisting tool for locating acupoints in meridianology practice class should be considered for improving accuracy in acupoint location.

• Environmental Mutagens and Carcinogens
• /
• v.18 no.1
• /
• pp.15-21
• /
• 1998

Transgenic animal and cell line models which are recently developed and used in toxicology fields combined with molecular biological technique, are powerful tools to study the mechanism of mutation in vivo and in vitro, respectively. Transgenic models, which have exogenous DNA incorporated into their genome, carry recoverable shuttle vector containing reporter genes to assess endogenous effects or alteration in specific genes related to disease processes. The lac I and lac Z gnee most widely used as a mutational target in transgenic systems. The assay is performed by treatment with putative mutagenic agents, isolation of genomic DNA from cells or tissues, exposure the isolated DNA to in vitro packaging extract, plating and sequencing. The results from these processes provide not only mutant frequency as quantitative evaluation but also mutational spectrum as qualitative evaluation of various agents. Therefore we introduce and review the principle, detailed procedure and application of transgenic mutagenesis assay system in toxicology fields especially in mutagenesis and carcinogenesis.