• Convergence Security Journal
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• v.6 no.3
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• pp.145-153
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• 2006

Infinite failure NHPP models for a record value satisfies mode proposed in the literature exhibit either monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, propose comparative study of software reliability model using Erlang distribution, Rayleigh and Gumbel distribution. Equations to estimate the parameters using maximum likelihood estimation of infinite failure NHPP model based on failure data collected in the form of interfailure times are developed. For the sake of proposing distribution, we used to the special pattern. Analysis of failure data set using arithmetic and Laplace trend tests, goodness-of-fit test, bias tests is presented.

• The Korean Journal of Archival Studies
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• no.17
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• pp.85-114
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• 2008

One of the features of record management during the Gabo Reform is that the documents office controled producing and distribution of records. The records completed the operations were sent the record office and classified and arranged. previous researches understood this record management system during Gabo Reform were introduced from Japan. This article clarifies that new record management system settled through Meiji Restoration were introduced from German(Prussian) registry system at the time. However, German registry system managed current records and this system was based on modern record management system which open the records to the public with archives. Japan accepted only registry system, current record management system of German, and didn't established archives at Meiji regime. It is same with Joseon Dynasty during the Gabo Reform regime. Therefore, the record related regulation at the Gabo Reform regime could not be judged to be a modern system. The regulations on records at Gabo Reform regime had no terms about people's right or open the records to the public which decides modern record regulations. The meaning of record system during Gabo Reform regime is that the value of records and name of organizations coincides with record life cycle. The documents office managed current records and record office classified and filed closed records. Concept of "current record=document=documents office, non-current record=record= record office" didn't succeed to today. The term 'record' is used as current record or non-current record without difference.

• Journal of the Chungcheong Mathematical Society
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• v.24 no.3
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• pp.401-407
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• 2011

The paper deals with characterization of standard Gumbel distribution and standard $Fr{\acute{e}}chet$ distribution and was motivated by [4], where the Weibull distribution is characterized. We present criterions using the independence of some suitable functions of lower records in a sequence of independent identically distributed random variables $\{X_n,\;n{\geq}1\}$.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.4
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• pp.194-202
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• 2019

Reliability analysis of the components frequently starts with the data that manufacturer provides. If enough failure data are collected from the field operations, the reliability should be recomputed and updated on the basis of the field failure data. However, when the failure time record for a component contains only a few observations, all statistical methodologies are limited. In this case, where the failure records for multiple number of identical components are available, a valid alternative is combining all the data from each component into one data set with enough sample size and utilizing the useful information in the censored data. The ROK Navy has been operating multiple Patrol Killer Guided missiles (PKGs) for several years. The Korea Multi-Function Control Console (KMFCC) is one of key components in PKG combat system. The maintenance record for the KMFCC contains less than ten failure observations and a censored datum. This paper proposes a Bayesian approach with a Dirichlet mixture model to estimate failure time density for KMFCC. Trends test for each component record indicated that null hypothesis, that failure occurrence is renewal process, is not rejected. Since the KMFCCs have been functioning under different operating environment, the failure time distribution may be a composition of a number of unknown distributions, i.e. a mixture distribution, rather than a single distribution. The Dirichlet mixture model was coded as probabilistic programming in Python using PyMC3. Then Markov Chain Monte Carlo (MCMC) sampling technique employed in PyMC3 probabilistically estimated the parameters' posterior distribution through the Dirichlet mixture model. The simulation results revealed that the mixture models provide superior fits to the combined data set over single models.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.593-598
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• 2005

At-site analysis is not appropriate if the record length is shorter than target return period T. If the record length is longer than 27 years, then at-site analysis may be sufficient(Institute of Hydrology, 1999). However, in such a case, regional frequency analysis is recommended for purpose of comparison. Record lengths of annual maximum rainfall data in Korea are usually shorter than 50 years. It is therefore essential to apply regional frequency analysis for estimating rainfall quantiles of more than 100 years return period. In this research, regional rainfall frequency analysis is performed for hourly rainfall data of South Korea. Homogeneous regions are idntified by clusgter analysis which is a standard method of statistical multivariate analysis for dividing a data set into groups. An appropriate distribution is chosen by goodness-of-fit test. GLO is found to be an appropriate distribution as a result of goodness-of-fit measure (Hosking & Wallis, 1997). Simulation experiments are performed to check the performance of frequency analysis techniques. The effects of discordant sites on quantiles are considered.

• Journal of Species Research
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• v.11 no.1
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• pp.38-46
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• 2022

This study is based on crane fly specimens collected during more than 80 years, starting from 1938 through 2019, in the Republic of Korea and Democratic People's Republic of Korea and are in collections maintained at the United States National Museum, Smithsonian Institution, Washington DC, USA; the Snow Entomological Museum, University of Kansas, Lawrence, KS, USA; and the National Institute of Biological Resources, Incheon, South Korea. Pilaria crane flies are aquatic and semiaquatic, developing in fast running and stagnant water bodies and in wet muddy places at the margins of water pools. Such habitats usually prevail at lower altitudes, but these areas most often are used for agriculture and human settlement, making natural habitats scarce and fragmented. Pilaria crane flies are rare, thus it is not surprising that genus was left unnoticed by previous researchers. The genus Pilaria Sintenis, 1889 with two species P. melanota Alexander, 1922 and P. simulans Savchenko, 1983, is a new record for the Korean Peninsula. We present general information on the genus, redescriptions of species based on Korean specimens, illustrations of both sexes, elevation range, period of activity, habitat information, general distribution, and a distribution map for the Korean Peninsula for each species.

• Korean Association of Arts Management
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• no.60
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• pp.37-68
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• 2021

The purpose of this study is to understand the attractiveness of the vinyl record industry and derive implications by analyzing the structure of the industry. A few previous studies pay attention to the rapidly increasing demand for vinyl records, especially from a consumer point of view, and unlike the analysis of the consumption and vinyl record industry, this study focuses on the subjects of production and distribution of vinyl records. This paper collects data through in-depth interviews with experts in the vinyl record industry and various secondary data, which is analyzed by Porter(1980/2008)'s Five Forces Model. According to the analysis, the attractiveness of the vinyl record industry is positive in terms of the appropriate competitive strength in the industry and weak bargaining power of buyers, but negative in terms of the strong bargaining power of new entrants and substitutes. The outcome of this research has significance as basic data implying that companies that are trying to enter the vinyl record industry need to make strategic decisions.

• Korean Journal of Plant Taxonomy
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• v.48 no.2
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• pp.123-128
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• 2018

Earlier taxonomic studies of Korean Scutellaria reported a new record of Scutellaria hastifolia L. in Korea based on three herbarium sheets. During a reexamination of these specimens, we found that the leaf characters of these specimens differ from those in the type specimen of S. hastifolia. Based on a literature survey and confirmation of the type specimen, the specimens identified as S. hastifolia thus far were a misidentification of S. barbata D. Don. S. hastifolia is clearly different from S. barbata by single conspicuous teeth on both sides of the leaf margins and larger leaves. In addition to the distribution sites of the three specimens used in the previous study, a distribution site of the S. barbata was newly found in the southern part of Korea. In this study, we report a new distribution of S. barbata in Korea, correct a previous report of S. hastifolia, describe the morphological characters of S. barbata, and suggest a taxonomic key to Korean Scutellaria including S. barbata.

• Mycobiology
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• v.37 no.1
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• pp.1-4
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• 2009

Calyptella capula is reported for the first time in Korea. It was found in spring in Chungcheongbuk-do, central Korea, growing in a dead stalk of Sesamum indicum. A description and molecular phylogenetic analyses are reported.

• Journal of Species Research
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• v.7 no.4
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• pp.333-339
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• 2018

Rotifers collected from Duung and Gyeongpo wetlands in Korea were investigated. Five species belonging to five genera in four families of monogonont rotifers were identified: Cephalodella ventripes (Dixon-Nuttall), Dicranophorus grandis (Ehrenberg), Lecane undulata Hauer, Taphrocampa selenura Gosse, and Testudinella emarginula (Stenroos). All these species are new to the Korean fauna, even though they have very wide or cosmopolitan distributions. The present study is the first report on the genus Taphrocampa Gosse from Korea. The taxonomy and distribution of each new Korean record are briefly discussed here. The diagnostic characteristics, photomicrographs and the deposition of voucher specimen are provided for each new Korean record.