• 제목/요약/키워드: GMMA

검색결과 6건 처리시간 0.019초

가변 스텝 크기 MSAG-GMMA 적응 블라인드 등화 알고리즘의 성능 평가 (A Performance Evaluation of Blind Equalization Algorithma for a Variable Step-Size MSAG-GMMA)

  • 정영화
    • 한국인터넷방송통신학회논문지
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    • 제18권3호
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    • pp.77-82
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    • 2018
  • 본 논문은 가변 스텝 크기를 가지는 MSAG-GMMA(modified Stop-and-Go generalized multi modulus algorithm) 적응 블라인드 등화 알고리즘의 성능 분석에 관한 것이다. 제안한 알고리즘은 등화 계수 갱신 식에서 고정 스텝 크기에 결정지향 알고리즘의 오차신호의 크기를 곱하여 오차크기에 따라서 스텝 크기가 변하도록 하였다. 또한 결정지향 알고리즘의 오차신호의 크기를 판단하여 어느 임계값 이상에서는 정상상태로의 빠른 수렴 속도를 유지하도록 스텝 크기가 고정인 값을 가지는 MSAG-GMMA가 동작하고, 미만일 때는 스텝 크기가 가변되는 MSAG-GMMA가 동작하도록 하였다. 제안한 알고리즘의 성능을 평가하기 위하여 성능 지수로 앙상블 ISI, 앙상블-평균 MSE, 그리고 등화기의 출력으로 얻어지는 등화 후 신호점도를 사용하였다. 모의실험을 통하여 제안한 알고리즘이 MMA, GMMA, 그리고 MSAG-GMMA보다 빠른 수렴 속도와 정상상태에서 작은 잔류 오차를 가짐을 확인하였다.

Evaluation of anxiety level changes during the first three months of orthodontic treatment

  • Yildirim, Ersin;Karacay, Seniz
    • 대한치과교정학회지
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    • 제42권4호
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    • pp.201-206
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    • 2012
  • Objective: To determine the changes in dental anxiety, state anxiety, and trait anxiety levels of patients and their parents after 3 months of active orthodontic treatment. Methods: We evaluated 120 patients and one parent of each patient. State Anxiety (STAI-S), Trait Anxiety (STAI-T), and Corah's Dental Anxiety Scale (DAS) were administered before orthodontic treatment (T1) and after 3 months of treatment (T2). Differences in scores between T1 and T2 were compared using paired-sample t-tests and the relationship between the scores of the DAS and the STAI were analyzed using a bivariate two-tailed Pearson correlation test. Results: Dental anxiety and state anxiety levels decreased among the patients after adjustment to orthodontic treatment (p < 0.001). However, 3 months of treatment was not sufficient to decrease the anxiety levels of parents (p > 0.05). Patient trait anxiety affected patient state anxiety and dental anxiety (p < 0.01). Additionally, a significant correlation was found between patient dental anxiety and parent dental anxiety (p < 0.05). Conclusions: Dental anxiety and state anxiety levels decrease after patients become familiar with their orthodontist and they became accustomed to orthodontic treatment. However, 3 months is not a sufficient length of time to decrease parental anxiety levels.

Determining the Awareness of and Compliance with Breast Cancer Screening among Turkish Residential Women

  • Yilmaz, Demet;Bebis, Hatice;Ortabag, Tulay
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권5호
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    • pp.3281-3288
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    • 2013
  • Background: Breast cancer is the leading cause of cancer-related deaths in women. Despite being associated with high morbidity and mortality, breast cancer is a disease that can be diagnosed and treated early. Materials and Methods: In this cross-sectional study of 321 women, data were collected by Questionnaire, Breast Cancer Risk Assessment Form and Champion's Health Belief Model Scale. Mann-Whitney U, Kruskal-Wallis, Chisquared tests and logistic regression were used in the statistical analysis. Results: It was found that only 2.2% of women have high and very high risk levels of breast cancer risk. There is a positive correlation between early diagnosis techniques and Health Belief Model Sub-Dimension scores which are sensibility, health motivation, BSE (Breast self-examination) self-efficient perception and negative correlation between mammography barrier score and BSE barrier score (p 0.05). When factors for not having BSE were examined, it was determined that the women who do not have information about breast cancer and the women who smoke have a higher risk of not having BSE. Conclusions: It is important to determine health beliefs and breast cancer risk levels of women to increase the frequency of early diagnosis. Women's health beliefs are thought to be a good guide for planning health education programs for nurses working in this area.

곽향(Agastache rugosa)을 포함한 21종의 한약재가 대식세포주 RAW 264.7 세포의 nitric oxide(NO) 생산 조절에 미치는 효과 (Modulatory Effects of 21 kinds of Medicinal Herbs Including Herba Pogostemi (Agastache rugosa) on Nitric Oxide Production in Macrophage Cell line RAW 264.7 cells)

  • 김승현;강미영;남석현
    • Applied Biological Chemistry
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    • 제48권4호
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    • pp.411-417
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    • 2005
  • 마우스 대식세포주인 RAW264.7 세포에서 곽향(Agastache rugosa)을 포함한 21종의 한약재에서 제조한 열수추출물의 NO생산에 대한 조절효과를 조사하였다. 모든 한약재 추출물은 LPS자극으로 생산된 NO에 대하여 뚜렷한 소거활성을 보이지 않았으나, LPS 무처리 조건에서 곽향이 RAW264.7 세포의 NO생산을 강력하게 유도하였다. $200{\mu}M$의 NOS2의 저해제인 $N^G-monomethyl-L-arginine(N^GMMA$)의 처리에 의하여 곽향이 유도하는 NO 생산은 유의적으로 감소되었다. 또한 $NF-{\kappa}B$ 저해제인 pyrrolidine dithiocarbamate(PDTC)의 처리로 NO 생산이 $100{\mu}M$에서 약 79%까지 감소하였다. 이상의 실험 결과는 곽향 열수추출물이 RAW264.7 세포의 NOS2 발현의 이차적인 세포 내 신호를 발생시킬 수 있으며, NO는 L-arginine 의존적 경로에 의하여 생성된다는 사실을 시사하였다.

Fabrication and Characterization of Modified Poly(2-hydroxyethyl methacrylate)(PHEMA) Hydrogels by Thermal/Photo Polymerization

  • Lee, Minsu;Lee, Junghyun;Jang, Jihye;Nah, Changwoon;Huh, Yang-il
    • Elastomers and Composites
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    • 제54권4호
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    • pp.359-367
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    • 2019
  • Poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogels modified with various co-monomers, such as N-vinyl pyrrolidone (NVP), glycidyl methacrylate (GMA), and glycerol monomethacrylate (GMMA), were prepared to investigate the effect of adding a co-monomer on the water contents, surface wettability, and tensile modulus. These polymers were synthesized by thermal- and photo-polymerization in the presence of azobisisobutyronitrile (AIBN) and diphenyl(2,4,6-trimethylbenzoyl)-phosphineoxide (TPO) as the initiators. The characteristics of the hydrogels were analyzed via FTIR and UV/Vis spectroscopies, contact angle measurements, and tensile modulus measurements with UTM. Regarding the properties of water in the hydrogels, the ratio between free to bound water was investigated using differential scanning calorimetry (DSC). The effects of adding the co-monomers on the water content, surface wettability, and tensile modulus for soft contact lenses were also investigated. In the case of p(HEMA-co-NVP) hydrogels, the increase in the equilibrium water content (EWC) was primarily due to the increase in the bound water content. For p(HEMA-co-GMMA) hydrogels, an increase in free water content was the main reason for the increased EWC. In contrast, in the case of p(HEMA-co-GMA) hydrogels, a decrease in bound water content was observed to be the main factor that reduced the EWC. Photo-polymerized PHEMA hydrogels showed enhanced surface wettability and tensile modulus as compared to those produced via thermal polymerization.

트롬본 장치를 이용한 하악궁 확장 (Expansion of the mandibular arch using a trombone appliance)

  • Sabuncuoglu, Fidan Alakus;Karacay, Seniz;Olmez, Huseyin
    • 대한치과교정학회지
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    • 제41권3호
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    • pp.211-218
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    • 2011
  • Objective: This case report describes orthodontic treatment of contracted mandibular arch using a trombone appliance. Methods: A 14-year-old girl with Class II division 2 malocclusion, retroclined maxillary incisors, and buccally displaced maxillary canines required dental expansion in 3 spatial directions to correct the contracted maxillary and mandibular arches. In the initial phase of treatment, the maxillary arch was expanded and distalized using a quad-helix appliance and cervical headgear. Following the expansion and leveling of the maxillary arch, a trombone appliance was used to expand the mandibular arch. On correction of the mandibular arch and provision of sufficient space to level the mandibular teeth, fixed orthodontic treatment phase was initiated. Results: A trombone appliance proved effective in correcting the contracted mandibular arch. Because of labiolingual and transversal expansion, the mandibular dental arch perimeter was increased by 7.4 mm; the misalignment of the mandibular teeth was corrected successfully. Conclusions: A trombone appliance may serve as an appropriate clinical alternative for treating moderate mandibular arch crowding caused by the contraction of the dental arch.