• 제목/요약/키워드: extrinsic mean

검색결과 30건 처리시간 0.025초

초등학생의 읽기동기에 관한 연구 : 읽기동기의 구성요인, 학년과 성차이를 중심으로 (Factors of Motivation for Reading : Differences between Grades and Gender)

  • 권민균
    • 아동학회지
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    • 제23권3호
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    • pp.17-33
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    • 2002
  • This study analyzed various factors of reading motivation and motivational differences between grades and gender. An urban sample of first-, third- and fifth- grade children completed the Motivation for Reading Questionnaire (MRQ; Wigfield & Guthrie, 1997). The MRQ assesses such possible factors of reading motivation as self-efficacy, intrinsic-extrinsic reading motives, and social aspects of reading. Factor analyses and cronbach's ${\alpha}$ demonstrated that 10 factors of children's reading motivation could be identified and measured reliably. Mean scores on most of the factors differed by grade and gender, with girls and lower grades reporting stronger motivation. This study found that children's reading motivation is various and decreases as children mature. Various efforts to encourage children's motivation for reading are suggested in this study.

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EXIT 차트분석을 이용한 SC-MMSE기반 반복수신기의 성능 증대 (Improving Iterative Detection and Decoding Based on SC-MMSE with EXIT Analysis)

  • 남준영;김성락;정현규
    • 정보와 통신
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    • 제24권12호
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    • pp.14-21
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    • 2007
  • This paper aims to improve the design of iterative detection and decoding(IDD) based on the soft interference cancellation with minimum mean squared error(SC-MMSE) detector, which shows low performance compared to the maximum a posteriori(MAP) detector. By means of extrinsic information transfer(EXIT) chart analysis, such low performance may be attributed to that the "pure"(original) turbo principle is not always best for IDD. Thus, we propose a new IDD architecture based on the SC-MMSE detector which uses new a priori information. Simulation results show that the performance of the proposed IDD is very close to that of IDD based on the MAP detector.

디지털 이동통신 시스템에서 연판정 출력의 차이값에 대한 절대평균값을 이용한 채널부호화 알고리즘 (Channel Coding Algorithm using Absolute Mean Values for the Difference Values of Soft Output in Digital Mobile Communication System)

  • 정대호;김환용;임순자
    • 대한전자공학회논문지SD
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    • 제44권10호
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    • pp.67-74
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    • 2007
  • 터보부호는 디지털 이동통신 시스템에서 사용되는 채널부호화 기법의 일종으로서 다양한 채널 환경에서 반복 횟수가 증가하면 복호하는데 필요한 지연시간과 계산량이 증가하는 단점을 가진다. 본 논문에서는 터보 복호기의 현재 복호 과정에서 첫번째 복호기와 두 번째 복호기의 연판정 출력값의 차이값에 대한 절대평균값을 중단조건으로 이용하여 BER 성능의 손실없이 모든 SNR 영역에서 평균 반복복호 횟수를 크게 감소시킬 수 있는 효율적인 반복중단 알고리즘을 제안한다. 모의실험 결과, 제안된 알고리즘의 평균 반복복호 횟수는 낮은 SNR 영역에서 SDR 알고리즘과 비교하여 약 $18.25%{\sim}20.58%$ 정도의 감소효과를 나타냈으며, 높은 SNR 영역에서 외부정보 값에 대한 분산값을 이용한 방법과 비교하여 약 $22.96%{\sim}28.74%$ 정도의 감소효과를 나타내었다.

Improvement of Graphene's Electrical Properties by ICP Cleaning

  • 강사랑;라창호;유원종
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.629-629
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    • 2013
  • Graphene is a carbon based material and it has intriguing features, such as phenomenally strong, thin, flexible, transparent and conductive, those make it attractive for a broad range of applications.Unfortunately, graphene is extremely sensitive to contamination. When we fabricate graphene devices, electrical properties of graphene are altered [1], and the charge carrier mobility drops accordingly by orders of magnitude. This significant impact on electron mobility occurs because any surrounding medium could act as a dominant source of extrinsic scattering, which effectively reduces the mean free path of carriers [2,3]. The dominant contaminant is generated through fabrication stage by polymethyl methacrylate (PMMA) [4], or photo resist (PR). Surface contamination by these residues has long been a critical problem in probing graphene's intrinsic properties. If we clearly solve this problem, we can get highly performed graphene devices. Here, we will report on graphene cleaning process by Induced Coupled Plasma (ICP). We demonstrated how much decomposition of residue impact on improving electrical properties of graphene.

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Epipolar 기하학을 이용한 2차원 투영 데이터의 3차원 표현에 관한 연구 (A Study on the 3D Representation of 2D Projection Data using Epipolar Geometry)

  • 유선국;;김남현;김용욱;김희중
    • 대한전기학회논문지:시스템및제어부문D
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    • 제51권5호
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    • pp.212-219
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    • 2002
  • In this paper, the epipolar geometry, genera17y used as a pin-hole camera model, is newly adapted to our proposed method that enables the affine reconstruction of the 3D object from two projected views. The proposed method models the projective projection of inherent X-ray imaging system, obviates the need to attach artifirially constructed material on the body, and requires none of the prior-knowledge regarding to intrinsic and extrinsic parameters of two X-ray imaging systems. The optimum numerical solution is obtained by applying the least mean square estimator to corresponding points on two projected X-ray planes. The performance of this proposed method is Quantitatively analyzed using computer synthesized model of Cochlear implantation electrodes. In simulated experiments, the propnsed method is insensitive to the added random noise, the scaling factor change, the center point change, and rotational angular change between two projection planes, as well as enables the stable 3D reconstruction in least square sense even in worst testing cases.

Correlation of Hormone Receptor and HER-2/neu Expression with Clinicopathologic Parameters in Primary Breast Tumors

  • Shaikh, Fouzia;Jamal, Qamar;Baig, Saeeda;Hadi, Naila Irum;Majeed, Noman
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권7호
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    • pp.3363-3367
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    • 2016
  • Background: Breast cancer (BC) is a major health issue worldwide as well as in Pakistan. All women belonging to any race, ethnicity or lineage are in danger of developing breast cancer. Significant factors influencing the development of breast malignancies are the genetic background, environmental conditions, reproductive parameters, the consequences of female hormones both intrinsic and extrinsic, alteration of immune status, and biologic determinants. Materials and Methods: Overall 150 biopsy proven patients were included in the study. Samples were submitted for histopathology and determination of estrogen and progesterone receptor expression and HER-2/neu status. Associations with other characteristics like age, tumor stage, node involvement, histological grade were also studied. Results: Mean age at presentation was 46.7 years. The majority had invasive ductal carcinoma, 100 (84.7%), and were in stage pT3, 54 (45.7%). Important relationships (P<0.05) were found among ER, PR positivity, and Her 2 neu overexpression. However, no noteworthy link was identified amongst ER, PR, Her 2 neu and tumor grade, stage, age, lymph node involvement except for the menopausal status. Conclusions: In summary, breast cancer patients featured an advanced stage of disease, more lymph node involvement, and moderately high grade tumors and with more estrogen, progesterone receptor and HER-2 positive tumors.

하지의 난치성 창상치유에 있어 VAC(Vacuum-Assisted Closure)의 유용성 (The Efficiency of VAC(Vacuum-Assisted Closure) in Non-healing Wound)

  • 박정민;권용석;정기환;이근철;김석권;안원석
    • Archives of Plastic Surgery
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    • 제32권6호
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    • pp.727-732
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    • 2005
  • The treatment of wounds of the lower extremity caused by diabetes or vascular dysfunction remains a difficult problem for the plastic surgeon. The use of negative pressure in wound healing is a relatively new method to facilitate chronic wound healing by secondary healing. The use of vacuum-assisted closure(VAC) system is purposed to reduce local edema, increase regional blood flow, enhance epithelial migration, preserve a moist wound environment, reduce bacterial colonization, promote granulation tissue formation, and mechanically enhance wound closure. The VAC also can be used as a dressing for anchoring an applied split thickness skin graft. We reviewed the data from 20 consecutive patients with non-healing wound in lower extremity at Dong-A University from March 2002 to December 2004. We used the VAC in 20 patients and compared the results with the control group. In the VAC using group, mean application duration was about 3 weeks and dressing change was done every other day. The follow-up period of patients ranged from 3 months to 30 months with a mean of 17 months. The points of comparison with control group are wound size, granulation tissue proliferation rate, operation method, preoperative time, postoperative healing time, complication, and cost. With those points, we propose to approve the efficiency of the VAC in non-healing wound. As a result, the VAC used in non-healing wound decrease wound size, accelerate granulation tissue formation, do a wound closure with less invasive operation method, make less postoperative complication, can make operation time shorter. Therefore it is cost effect. Our results demonstrate the usefulness of VAC as an adjunct in management of chronic wounds with other extrinsic factors.

Comparisons of the prevalence of gallbladder polyps and clinical variables among residents between the urban and rural area on Jeju Island

  • Kwon, Oh-Sung;Kim, Young-Kyu
    • 한국컴퓨터정보학회논문지
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    • 제27권2호
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    • pp.195-201
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    • 2022
  • 시내 지역과 시외 지역 사이에서 담낭용종의 유병률과 일부 임상적 변수들이 다르다는 보고가 있으나 그것은 육지에서 시행되었다. 따라서 이전 연구는 혼동 요인들을 가질 수가 있다. 그래서 이 연구의 목적은 담낭용종의 유병률과 임상 변수들을 외부 혼동 요인들을 배제하기 위해서 고립된 섬에서 비교해 보고자 하였다. 우리는 제주도에서 담낭용종 유병률과 임상 변수들을 2009년 1월부터 2019년 12월까지 제주대학교병원 단일 건강검진센터에서 건강검진을 시행한 21,734명의 거주민들에서 그들의 주소지를 따라서 비교하였다. 시내 지역과 시외 지역 거주민들의 담낭용종 유병률은 각각 10.1%와 8.7% (P = 0.006)로 의미 있게 차이가 있었다. 임상 변수들 중에서, 중심 비만자의 비율, 평균 공복시 혈당, LDL-콜레스테롤, 평균 알카라인 인산분해효소와 감마-글루타밀전이효소 수치들과 평균 연령이 시내 지역보다 시외 지역에서 높았으나, 평균 총콜레스테롤 수치는 시내 지역 거주민들에서 시외 지역 거주민들보다 높았다. 이 연구는 제주도의 시내와 시내 지역 거주민들에서 담낭용종 유병률과 일부 임상적 변수들이 통계학적으로 다르다는 것을 보여 주었다.

저장온도에 따른 마른김(Pyropia pseudolinearis)의 Bacillus cereus 성장예측모델 개발 (Predictive Growth Models of Bacillus cereus on Dried Laver Pyropia pseudolinearis as Function of Storage Temperature)

  • 최만석;김지윤;전은비;박신영
    • 한국수산과학회지
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    • 제53권5호
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    • pp.699-706
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    • 2020
  • Predictive models in food microbiology are used for predicting microbial growth or death rates using mathematical and statistical tools considering the intrinsic and extrinsic factors of food. This study developed predictive growth models for Bacillus cereus on dried laver Pyropia pseudolinearis stored at different temperatures (5, 10, 15, 20, and 25℃). Primary models developed for specific growth rate (SGR), lag time (LT), and maximum population density (MPD) indicated a good fit (R2≥0.98) with the Gompertz equation. The SGR values were 0.03, 0.08, and 0.12, and the LT values were 12.64, 4.01, and 2.17 h, at the storage temperatures of 15, 20, and 25℃, respectively. Secondary models for the same parameters were determined via nonlinear regression as follows: SGR=0.0228-0.0069*T1+0.0005*T12; LT=113.0685-9.6256*T1+0.2079*T12; MPD=1.6630+0.4284*T1-0.0080*T12 (where T1 is the storage temperature). The appropriateness of the secondary models was validated using statistical indices, such as mean squared error (MSE<0.01), bias factor (0.99≤Bf≤1.07), and accuracy factor (1.01≤Af≤1.14). External validation was performed at three random temperatures, and the results were consistent with each other. Thus, these models may be useful for predicting the growth of B. cereus on dried laver.

자아효능감이 게임의 몰입에 미치는 영향 (A Study on Effect of the Equity and the Cognitive Performance on the Flow Experience of the Game playing)

  • 최동성;김진우
    • 한국게임학회 논문지
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    • 제9권3호
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    • pp.87-96
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    • 2009
  • 몰입이론과 관련된 연구결과에 의하면, 사람들이 어떤 일에 대해 최적의 경험을 하기 위해서 는 도전감(Challenge)과 능력(Skill)이 높았을 때라고 한다. 그렇다면 몰입이론의 능력(Skill)은 무엇을 의미하는가? 본 연구에서는 교육학에서 다루고 있는 자아효능감(Self-Efficacy)이론을 토대로 몰입이론에서 말하는 능력(Skill)에 대해 재해석하고, 실제 자아효능감에 영향을 미치는 게임의 요소와 자아효능감이 몰입의 경험에 미치는 영향을 설문을 통해 분석하였다. 분석결과를 살펴보면, 몰입에서의 능력(Skill)은 주관적 자기 능력의 의미로써 자아효능감과 동일한 개념임을 알 수 있었다. 또한 설문결과 게임의 보상에 대한 형평성과 타인의 긍정적 평가가 자아효능감에 영향을 미치고, 이를 통해 몰입의 경험을 하게 된다는 가설을 검증하였다. 본 연구 결과를 토대로 플레이어에게 몰입의 경험을 높게 제공하기 위해 자아효능감을 어떻게 게임 요소로 활용해야 하는지에 대한 이론적 근거를 제공해 줄 수 있을 것이다.

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