• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.267-268
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• 2015

The multi-environment probability density function model has been applied to simulate the turbulent $CH_4/H_2$ flames under MILD conditions. The direct quadrature method of moments (DQMOM) has been adopted to solve the transport PDF equation due to its computational efficiency and robustness. The IEM model represents the micromixing process. The numerical results obtained in this study are precisely compared with experimental data in terms of unconditional means and conditional means for scalar field including temperature and species mass fraction.

• 정보과학회 논문지
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• 제43권6호
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• pp.678-685
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• 2016

한국어 개체명 인식에 다양한 연구가 있었지만, 영어 개체명 인식에 비해 자질이 부족한 문제를 가지고 있다. 본 논문에서는 한국어 개체명 인식의 자질 부족 문제를 해결하기 위해 word embedding 자질을 개체명 인식에 사용하는 방법을 제안한다. CBOW(Continuous Bag-of-Words) 모델을 이용하여 word vector를 생성하고, word vector로부터 K-means 알고리즘을 이용하여 군집 정보를 생성한다. word vector와 군집 정보를 word embedding 자질로써 CRFs(Conditional Random Fields)에 사용한다. 실험 결과 TV 도메인과 Sports 도메인, IT 도메인에서 기본 시스템보다 각각 1.17%, 0.61%, 1.19% 성능이 향상되었다. 또한 제안 방법이 다른 개체명 인식 및 분류 시스템보다 성능이 향상되는 것을 보여 그 효용성을 입증했다.

• 정보처리학회논문지C
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• 제8C권1호
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• pp.75-87
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• 2001

이 논문에서는 제한수신시스템의 일반구조 및 암/복호화에 사용되는 키의 안정성을 위한 키관리 메카니즘 그리고 시스템 성능 향상을 위한 키 계층 구조의 개선에 대해서 살펴본다. 또한 시스템 성능 분석을 위한 기본 개념으로 큐잉 이론(queuing theory)을 설명하고, 디지털 방송 유료화 서비스의 실현 및 시스템 성능 향상을 위한 시스템 최적화 방안으로서 몇 가지 산정된 자료를 기초로 하여 최적의 키 생성 및 전달 주기, 최적의 키관리 주기에 따른 최대/최소 키 전달 시간, 과금 데이터처리를 위한 전용선의 용량 및 시스템 용량을 산정 한다.

• 한국콘텐츠학회논문지
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• 제5권3호
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• pp.209-215
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• 2005

본 논문에서는 정의형 질의응답 시스템을 위한 정답 패턴에 대하여 기술한다. 정의형 질의응답 시스템은 정의형 질의에 대한 정답으로 단답형 정답이 아닌 서술형 정답을 제공하기 때문에, 정답 추출 방법이 일반적인 단답형 정답 추출 방법과 다르다. 정의형 정답 패턴을 이용한 정의형 정답 추출은 의미 분석없이 정확한 정의형 정답을 추출할 수 있다. 정의형 정답 패턴은 정확한 정답 추출을 위해 정답 패턴과 패턴별 제약 규칙, 우선순위로 구성된다. 정의형 정답 학습 코퍼스로부터 정답 패턴을 추출하고, 각각의 정답 패턴에 대한F-measure에 따라 최적화하여 패턴별 제약 규칙을 구성한다. 마지막으로 정확률과 정답 패턴 구문 구조를 이용하여 우선순위를 결정한다. 제안한 정의형 정답 패턴을 이용한 정의형 정답 추출은 실험 코퍼스에 대해 정확률 0.8207, 재현율 0.9268, F-measure 0.8705를 보였다. 이것은 제안한 방법이 정의형 질의응답 시스템에 효율적으로 사용될 수 있음을 의미한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권9호
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• pp.4336-4354
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• 2018

Fuzzy C-means (FCM) algorithm is a most usually technique for medical image segmentation. But conventional FCM fails to perform well enough on magnetic resonance imaging (MRI) data with the noise and intensity inhomogeneity (IIH). In the paper, we propose a Gamma correction conditional FCM algorithm with spatial information (GcsFCM) to solve this problem. Firstly, the pre-processing, Gamma correction, is introduced to enhance the details of images. Secondly, the spatial information is introduced to reduce the effect of noise. Then we introduce the effective neighborhood mechanism into the local space information to improve the robustness for the noise and inhomogeneity. And the mechanism describes the degree of participation in generating local membership values and building clusters. Finally, the adjustment mechanism and the spatial information are combined into the weighted membership function. Experimental results on four image volumes with noise and IIH indicate that the proposed GcsFCM algorithm is more effective and robust to noise and IIH than the FCM, sFCM and csFCM algorithms.

• Journal of Information Processing Systems
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• 제15권6호
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• pp.1326-1334
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• 2019

Knowledge base means a library stored in computer system providing useful information or appropriate solutions to specific area. Knowledge base associated with autism is the complex multidimensional information set related to the disease autism for its pathogenic factor and therapy. This paper focuses on the knowledge of biological molecular information extracted from massive biomedical texts with the aid of widespread used machine learning methods. Six classes of biological molecular information (such as protein, DNA, RNA, cell line, cell component, and cell type) are concerned and the probability statistics method, conditional random fields (CRFs), is utilized to discover these knowledges in this work. The knowledge base can help biologists to etiological analysis and pharmacists to drug development, which can at least answer four questions in question-answering (QA) system, i.e., which proteins are most related to the disease autism, which DNAs play important role to the development of autism, which cell types have the correlation to autism and which cell components participate the process to autism. The work can be visited by the address http://134.175.110.97/bioinfo/index.jsp.

• 아태비즈니스연구
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• 제12권4호
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• pp.63-86
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• 2021

Purpose - The purpose of this study is to explore the impact of the application of accounting conservatism on the investment efficiency of listed companies in China under the background of the current rising environmental uncertainty. Design/methodology/approach - This study collected 14,934 observations of A-share listed companies in Shanghai and Shenzhen from 2013 to 2020, and analyzed the data by means of moderating effect test and multiple regression analysis. Findings - The results show that environmental uncertainty deteriorates the company's investment efficiency. The higher the level of environmental uncertainty, the more prone to over-investment and under-investment. Accounting conservatism plays moderating role between environmental uncertainty and investment efficiency. Among them, the moderating effect of conditional conservatism is to alleviate under-investment of the company under high financing constraints and the over-investment, while it intensifies the under-investment under low financing constraints. The moderating effect of unconditional conservatism is to alleviate the under-investment. Research implications or Originality - This study finds out the internal mechanism of accounting conservatism affecting investment efficiency, which not only helps to understand about the value of accounting conservatism standards, but also helps to improve the investment efficiency of listed companies.

• Asian-Australasian Journal of Animal Sciences
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• 제15권7호
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• pp.925-931
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• 2002

Gibbs sampling algorithms were implemented to the multi-trait threshold animal models with any combinations of multiple binary, ordered categorical, and linear traits and investigate the amount of bias on these models with two kinds of parameterization and algorithms for generating underlying liabilities. Statistical models which included additive genetic and residual effects as random and contemporary group effects as fixed were considered on the models using simulated data. The fully conditional posterior means of heritabilities and genetic (residual) correlations were calculated from 1,000 samples retained every 10th samples after 15,000 samples discarded as "burn-in" period. Under the models considered, several combinations of three traits with binary, multiple ordered categories, and continuous were analyzed. Five replicates were carried out. Estimates for heritabilities and genetic (residual) correlations as the posterior means were unbiased when underlying liabilities for a categorical trait were generated given by underlying liabilities of the other traits and threshold estimates were rescaled. Otherwise, when parameterizing threshold of zero and residual variance of one for binary traits, heritability estimates were inflated 7-10% upward. Genetic correlation estimates were biased upward if positively correlated and downward if negatively correlated when underling liabilities were generated without accounting for correlated traits on prior information. Residual correlation estimates were, consequently, much biased downward if positively correlated and upward if negatively correlated in that case. The more categorical trait had categories, the better mixing rate was shown.

• 동력기계공학회지
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• 제13권2호
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• pp.63-70
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• 2009

This paper discusses the influence on long-tenn predictions of the ship response in ocean by using the Global Wave Statistics data, GWS, and wave information from the remote sensing satellites. GWS's standard scatter diagrams of significant wave height and zero-crossing wave period are suggested to be corrected to a round number of 0.01/1000 fitted with a statistical analytic model of the conditional lognormal distribution for zero-crossing wave period. The GEOSAT satellite data are utilized which presented by I. R. Young and G. J. Holland (1996, named as GEOSAT data). At first, qualities of this data are investigated, and statistical characteristic trends are studied by means of applying known probability distribution functions. The wave height data of GEOSAT are compared to the data observed onboard merchant ships, the data observed by measure instrument installed on the ocean-going container ship and so on. To execute a long-tenn prediction of ship response, joint probability functions between wave height and wave period are introduced, therefore long-term statistical predictions are executed by using the functions.

• 한국영어학회지:영어학
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• 제2권3호
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• pp.403-430
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• 2002

With a view to providing a unitary interpretation of a lexical item, even, this paper proposes that even be understood as a quantifier. To countenance this idea, the quantifier theories will be evaluated against the implicature accounts on the basis of conceptual and empirical evidence. With the help of Bach (1999), the quantifier theories of even are regarded as most viable and plausible. On the other hand, from among different quantifier approaches even will be viewed as a quasi-universal quantifier, which means that even is similar to the universal quantifier but still it is different from it. That is, even introduces a comparison set that is context-dependent and only the salient members of this comparison set will be taken into account when an even-sentence is to be uttered. This observation is based on the formal representation for a universal quantifier in general on the one hand and the truth-conditional contribution of even to the sentence containing it.