• 한국지능시스템학회논문지
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• 제26권6호
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• pp.485-492
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• 2016

이진화는 컴퓨터 비전 분야에서 전경과 배경을 분리하는 중요한 역할을 한다. 본 연구에서는 적응 퍼지 이진화 방법을 제안한다. 이동 창 내의 화소의 밝기 값 분포에 따라 ${\alpha}$-컷을 구하고, 이 값을 이용하여 이진화를 수행한다. ${\alpha}$-컷을 구하기 위해 수행속도가 빠른 기존의 이진화 방법들을 이용한다. 기존 방법들로 구해진 임계치들을 퍼지 소속 함수들의 중심값으로 설정하고, 화소의 밝기값 분포를 이용하여 퍼지 소속 함수들의 구간을 결정한다. 결정된 퍼지 소속 함수들을 이용하여 ${\alpha}$-컷의 조정율을 구하고, 각 화소의 소속도에 따라 이진화를 수행한다. 실험 결과는 제안한 방법이 기존의 방법들보다 전경과 배경이 효과적으로 분리될 수 있고, 전경의 손실이 적어지는 것을 보여준다.

• Kyungpook Mathematical Journal
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• 제53권3호
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• pp.435-457
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• 2013

Using the Lukasiewicz 3-valued implication operator, the notion of an (${\alpha},{\beta}$)-intuitionistic fuzzy left (right) $h$-ideal of a hemiring is introduced, where ${\alpha},{\beta}{\in}\{{\in},q,{\in}{\wedge}q,{\in}{\vee}q\}$. We define intuitionistic fuzzy left (right) $h$-ideal with thresholds ($s,t$) of a hemiring R and investigate their various properties. We characterize intuitionistic fuzzy left (right) $h$-ideal with thresholds ($s,t$) and (${\alpha},{\beta}$)-intuitionistic fuzzy left (right) $h$-ideal of a hemiring R by its level sets. We establish that an intuitionistic fuzzy set A of a hemiring R is a (${\in},{\in}$) (or (${\in},{\in}{\vee}q$) or (${\in}{\wedge}q,{\in}$)-intuitionistic fuzzy left (right) $h$-ideal of R if and only if A is an intuitionistic fuzzy left (right) $h$-ideal with thresholds (0, 1) (or (0, 0.5) or (0.5, 1)) of R respectively. It is also shown that A is a (${\in},{\in}$) (or (${\in},{\in}{\vee}q$) or (${\in}{\wedge}q,{\in}$))-intuitionistic fuzzy left (right) $h$-ideal if and only if for any $p{\in}$ (0, 1] (or $p{\in}$ (0, 0.5] or $p{\in}$ (0.5, 1] ), $A_p$ is a fuzzy left (right) $h$-ideal. Finally, we prove that an intuitionistic fuzzy set A of a hemiring R is an intuitionistic fuzzy left (right) $h$-ideal with thresholds ($s,t$) of R if and only if for any $p{\in}(s,t]$, the cut set $A_p$ is a fuzzy left (right) $h$-ideal of R.

• 한국콘텐츠학회논문지
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• 제7권10호
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• pp.19-26
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• 2007

협력적 필터링은 아이템에 대한 선호도를 기반으로 이웃 선정 방법을 사용하므로 내용을 반영하지 못할뿐만 아니라 희박성 및 확장성 문제를 가지고 있다. 이러한 문제를 개선하기 위하여 아이템 기반 협력적 필터링이 실용화되었으나 아이템의 속성을 반영하지는 못한다. 본 논문에서는 기존의 개인화 추천 시스템의 문제점을 해결하기 위하여 FP-Tree를 이용한 연관 군집 방법을 제안하였다. 제안된 방법으로는 FP-Tree를 이용하여 후보집합의 발생없이 빈발항목을 구성하고 연관규칙을 생성한다. 생성된 연관 규칙의 신뢰도에 따라서 $\alpha-cut$을 사용하여 효율적인 연관 군집을 한다. 성능평가를 위해 MovieLens 데이터 집합에서 Gibbs Sampling, EM, K-means와 비교 평가하였다.

• Journal of Advanced Marine Engineering and Technology
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• 제16권5호
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• pp.39-49
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• 1992

The dynamic design object of rotor system is to optimize the system in stability at the operating speed, unbalance response in the vicinity of the rotor critical speed, bearing weighting and system weighting. In conventional optimization method, designers have to set mathematical modeling, such as objective function, constraints and design parameters, strictly and quantitavely. But in actual design process, they do not treat all of these values strictly and some of them are somehow "fuzziness". So, considering boundary conditions of seal diameter, clearance, and length in a typical double suction centrifugal pump is fuzzy, this paper is considered fuzzy in constraints. Fuzzy method is used .alpha.-level cut method. Then, the optimum dimensions of seal according to values are obtained and vibration characteristics are investigated.estigated.

• 한국방사선학회논문지
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• 제16권3호
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• pp.217-223
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• 2022

본 연구는 엑스선 흉부촬영에서 격자를 이용하여 촬영법과 Air Gap Technique을 이용한 촬영법에서 얻은 영상을 평가하기 위하여 대학병원 영상의학과에서 10년 이상 근무한 방사선사 선생님 5인에게 주관적 평가 ROC와 객관적 평가 SNR를 시행하였다. 분석한 결과는 Cronbach Alpha 값이 0.714로 유의하게 높았다. Air Gap Technique 촬영법에서 팬톰과 상수용체 간격을 20 cm 띄우고 관전압 100 kVp, 관전류와 촬영시간 8 mAs로 설정하고 촬영한 영상을 ROC 평가에서 18점, SNR 평가에서 6.149로 가장 높은 점수를 얻었다. 또한 격자를 이용하여 촬영법에서는 팬톰과 상수용체 간격을 15 cm 띄우고 관전압 110 kVp, 관전류와 촬영시간을 8 mAs에서 촬영 시 ROC 평가점수가 19점과 객관적평가인 신호대잡음비(SNR)가 6,622으로 가장 높은 점수를 받았다. 이에 격자를 이용하여 나타나는 격자의 cut-off 현상으로 인하여 재촬영뿐만 아니라 판독지연, 환자의 피폭선량 증가, 기계적 수명단축 등의 단점을 벗어나는 Air Gap Technique 촬영법을 활용한다면, 중환자실 및 응급환자를 위한 이동형 엑스선 촬영장비를 사용할 경우를 포함하여 흉부 촬영 시에 많은 도움이 되리라 사료된다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6319-6325
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• 2012

We previously found cytotoxic effects of tomato leaf extract (TLE) on the MCF-7 breast cancer cell line. The aim of this study was to ascertain the molecular mechanisms associated with the usage of TLE as an anticancer agent by microarray analysis using mRNA from MCF-7 breast cancer cells after treatment with TLE for 1 hr and 48 hrs. Approximately 991 genes out of the 30,000 genes in the human genome were significantly (p<0.05) changed after the treatment. Within this gene set, 88 were significantly changed between the TLE treated cells and the untreated MCF-7 cells (control cells) with a cut-off fold change >2.00. In order to focus on genes that were involved in cancer cell growth, only twenty-nine genes were selected, either down-regulated or up-regulated after treatment with TLE. Microarray assay results were confirmed by analyzing 10 of the most up and down regulated genes related to cancer cells progression using real-time PCR. Treatment with TLE induced significant up-regulation in the expression of the CRYAB, PIM1, BTG1, CYR61, HIF1-${\alpha}$ and CEBP-${\beta}$ genes after 1 hr and 48 hrs, whereas the TXNIP and THBS1 genes were up-regulated after 1 hr of treatment but down-regulated after 48 hrs. In addition both the HMG1L1 and HIST2H3D genes were down-regulated after 1 hr and 48 hrs of treatment. These results demonstrate the potent activity of TLE as an anticancer agent.

• Restorative Dentistry and Endodontics
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• 제41권1호
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• pp.1-5
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• 2016

Objectives: The purpose of this study was to assess the ability of ProTaper Gold (PTG, Dentsply Maillefer) in maintaining the original profile of root canal anatomy. For that, ProTaper Universal (PTU, Dentsply Maillefer) was used as reference techniques for comparison. Materials and Methods: Twenty simulated curved canals manufactured in clear resin blocks were randomly assigned to 2 groups (n = 10) according to the system used for canal instrumentation: PTU and PTG groups, upto F2 files (25/0.08). Color stereomicroscopic images from each block were taken exactly at the same position before and after instrumentation. All image processing and data analysis were performed with an open source program (FIJI). Evaluation of canal transportation was obtained for two independent canal regions: straight and curved levels. Student's t test was used with a cut-off for significance set at ${\alpha}=5%$. Results: Instrumentation systems significantly influenced canal transportation (p < 0.0001). A significant interaction between instrumentation system and root canal level (p < 0.0001) was found. PTU and PTG systems produced similar canal transportation at the straight part, while PTG system resulted in lower canal transportation than PTU system at the curved part. Canal transportation was higher at the curved canal portion (p < 0.0001). Conclusions: PTG system produced overall less canal transportation in the curved portion when compared to PTU system.