• 제목/요약/키워드: Correlation efficiency

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Intra-picture Block-matching Method for Codebook-based Texture Compression

  • Cui, Li;Jang, Euee S.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권10호
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    • pp.5063-5073
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    • 2016
  • In this paper, an efficient texture compression method is proposed for fast rendering, which exploits the spatial correlation among blocks through intra-picture block matching. Texture mapping is widely used to enhance the visual quality of results in real-time rendering applications. For fast texture mapping, it is necessary to identify an effective trade-off between compression efficiency and computational complexity. The conventional compression methods utilized for image processing (e.g., JPEG) provide high compression efficiency while resulting in high complexity. Thus, low complexity methods, such as ETC1, are often used in real-time rendering applications. Although these methods can achieve low complexity, the compression efficiency is still lower than that of JPEG. To solve this problem, we propose a texture compression method by reducing the spatial redundancy between blocks in order to achieve the better compression performance than ETC1 while maintaining complexity that is lower than that of JPEG. Experimental results show that the proposed method achieves better compression efficiency than ETC1, and the decoding time is significantly reduced compared to JPEG while similar to ETC1.

Error Performance Analysis of DS-CDMA System in Wireless Channel

  • Kang, Heau-Jo
    • Journal of information and communication convergence engineering
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    • 제1권1호
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    • pp.1-5
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    • 2003
  • This paper discusses the spectral efficiency and performance of asynchronous direct sequency spread spectrum multiple access systems strict bandwidth limitation by Nyquist filtering. The signal to noise plus interference ratio(SNIR) at the output from the correlation receiver is derived analytically taking the cross correlation characteristics of spreading sequences into account, and also an approximated SNIR of a simple form is presented for the systems employing Gold sequences. Based on the analyzed result of SNIR, bit error rate performance and spectral efficiency are also estimated. and at last, we analyzed improvement rate using RS, convolution as a method for improving functions.

간호대학생의 메타인지, 자기효능감, 임상수행능력의 융복합적 영향 (Study on Meta-cognition, Self-efficiency, Clinical competence of nursing students)

  • 진은영;이명인;김윤이
    • 디지털융복합연구
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    • 제15권4호
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    • pp.317-326
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    • 2017
  • 본 연구는 간호대학생의 메타인지와 자기효능감 및 임상수행능력의 정도를 파악하고 임상수행능력에 영향을 주는 요인을 파악하고자 시도된 서술적 조사연구이다. 간호대학생 153명을 대상으로 자기보고형 설문지를 통해 2015년 9월1일부터 9월30일까지 자료를 수집하였다. SPSS/Win 18.0 프로그램을 이용하여, 빈도와 백분율, 평균과 표준편차, Pearson's Correlation coefficient, t-test, One-way ANOVA, 다중회귀분석을 사용하였다. 본 연구결과 메타인지와 자기효능감이 임상수행능력과 양의 상관관계가 있었다. 대상자의 특성 중 전공만족과 임상실습만족을 포함시켰을 때는 임상수행능력의 7%를 설명하였다(F=2.76, p=.030). 메타인지를 추가적으로 투입하였을 때는 임상수행능력이 25%의 설명력을 나타내었으며 자기효능감을 추가적으로 투입하였을 때는 임상수행능력이 27%의 설명력이 나타났다. 결론적으로 스스로의 문제해결능력이 강조되고 있는 간호현장의 상황을 고려할 때 임상수행능력 향상을 위해서는 체계적인 교육과정의 개발 및 다양한 교수학습방법의 활성화가 필요할 것으로 사료된다.

치위생과 학생의 자아탄력성과 자기효능감이 전공만족도에 미치는 영향 (Effect of self-resilience and self-efficiency on the satisfaction with major in dental hygiene students)

  • 최미숙;장영호;윤현경
    • 한국치위생학회지
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    • 제14권2호
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    • pp.155-162
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    • 2014
  • Objectives : The purpose of this study was to examine the effect of self-resilience and self-efficiency on the satisfaction with major in dental hygiene students. Methods : The data were analyzed by the frequency analysis, one-way ANOVA, Duncan post-hoc analysis, correlation analysis, multiple regression analysis using SPSS 18.0. The subjects were 411 dental hygiene students in A University in Gyeongsangbuk-do and K-University in Gyeongsangnam-do from November 4 to 15, 2013. Results : The satisfaction with major in dental hygiene students showed the positive correlation with self-resilience and self-efficiency. Multiple regression analysis revealed the optimistic attitude towards the self-resilience and self-efficiency. The explanation power was 13%. Conclusions : The self-resilience and self-efficiency had a positive effect on the satisfaction with major. It is necessary to develop the program that can help increase the self-resilience and self-efficiency, and apply such program to the curricula.

Quadratic inference functions in marginal models for longitudinal data with time-varying stochastic covariates

  • Cho, Gyo-Young;Dashnyam, Oyunchimeg
    • Journal of the Korean Data and Information Science Society
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    • 제24권3호
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    • pp.651-658
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    • 2013
  • For the marginal model and generalized estimating equations (GEE) method there is important full covariates conditional mean (FCCM) assumption which is pointed out by Pepe and Anderson (1994). With longitudinal data with time-varying stochastic covariates, this assumption may not necessarily hold. If this assumption is violated, the biased estimates of regression coefficients may result. But if a diagonal working correlation matrix is used, irrespective of whether the assumption is violated, the resulting estimates are (nearly) unbiased (Pan et al., 2000).The quadratic inference functions (QIF) method proposed by Qu et al. (2000) is the method based on generalized method of moment (GMM) using GEE. The QIF yields a substantial improvement in efficiency for the estimator of ${\beta}$ when the working correlation is misspecified, and equal efficiency to the GEE when the working correlation is correct (Qu et al., 2000).In this paper, we interest in whether the QIF can improve the results of the GEE method in the case of FCCM is violated. We show that the QIF with exchangeable and AR(1) working correlation matrix cannot be consistent and asymptotically normal in this case. Also it may not be efficient than GEE with independence working correlation. Our simulation studies verify the result.

변이불변 특성이 개선된 광굴절 상관기를 이용한 실시간 광 패턴인식 시스템 구현 (Implementation of real-time optical pattern recognition system using a photorefractive correlator with improved shift-invariant property)

  • 김성완;김철수;김종찬;김종윤;이승희;김수중
    • 전자공학회논문지D
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    • 제35D권3호
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    • pp.63-69
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    • 1998
  • In this paper, a new input method is proposed to improve shift-invariant property of a photorefractive correlator andwe implemented real-time optical pattern recognition system using it. In the conventional photorefractive correlator, it is vrey difficult to satisfy the Bragg condition in the pattern recognition process. So, correlation peak is decreased heavily for the shift of input image. If a liquid crystal television(LCTV) without an anlyzer is used as input device, we can get the correlation result regardless of shift of input image because beam path is not changed during storage of holographic filter and correlation process. Also recording time of a holographic matched filter in photorefractive crystal is reduced and the correlation peak is increased because incident beam on the LCTV is transmitted completely. Therefore total optical efficiency is improved. We compared and analyzed the correlation results of proposed photorefractive correlator by computer simulation and optical experiment. We used a BaTiO$_{3}$ single crystal which has high diffraction efficiency in optical experiment.

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장애인근로자의 사회적 지지, 자기효능감 및 우울이 직무 스트레스에 미치는 영향 (The Influence of Disabled Worker's Social Support, Self Efficiency & Depression on Job Stress)

  • 김연실;권명진;김시경
    • 한국직업건강간호학회지
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    • 제21권2호
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    • pp.116-124
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    • 2012
  • Purpose: This study was conducted to examine the influencing factors of social support, self efficiency and depression among the hearing-impaired and physically disabled on their job stress. Methods: The data were collected from Jan.1 to Aug. 30, 2010 from 151 disabled workers. The instruments for this study were the Korean Occupational Stress Scale (KOSS), Social Support Scale, General Self-Efficacy Scale and Beck Depression Inventory-Korean Version (K-BDI). The data were analyzed using t-test, Pearson correlation coefficient and multiple regression with the SPSS/WIN 18.0. Results: The physically disabled show higher social support (t=0.284, p= .001) and self efficacy (t=0.165, p= .024) but lower in depression (t=0.789, p<.001) than the hearing-impaired. There are negative correlation between job stress and social support, job stress and self efficacy but a positive correlation between job stress and depression. These three factors explained 42.9% of the variance in job stress. Conclusion: Social support and self efficacy have positive impacts on job stress but depression has negative impact.

빗물펌프장에 설치된 인공습지의 비점오염원 저감효율 연구 (A Study of Non-point Source Reduction Efficiency by Constructed Wetland installed in Flood Pumping Station)

  • 천석영;김지태;이일국;장순웅
    • 환경영향평가
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    • 제23권1호
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    • pp.67-74
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    • 2014
  • The aim of this study was evaluated the effects of total rainfall, rainfall intensity and antecedent dry days and identify the correlation analysis with the EMC removal efficiency, in order to provide an understanding of the operation and maintenance factors of constructed wetland in flood pumping station. This study was conducted total of 20 monitoring in a catchment(326.2 ha) of constructed wetland in Ga-un flood pumping station located at the downstream of the Wang-suk stream. The determined EMC removal efficiencies were $36.04{\pm}9.45%$ for BOD, $38.50{\pm}13.50%$ for $COD_{Mn}$, $34.34{\pm}13.05%$ for TN and $34.22{\pm}14.27%$ for TP, respectively. These results showed that the pollutants concentration and EMC were reduced while passing through the constructed wetland. In the correlation analysis, the highly correlations with EMC removal efficiency of BOD and $COD_{Mn}$ were observed for total rainfall and rainfall intensity (P<0.05). However, the correlations were not found with TN and TP for rainfall variables.

공공건물 옥상녹화와 설치태양광(PV)의 효율향상 상관관계 연구 (A Study on Correlation between Improvement in Efficiency of PV and Green roof of Public Building)

  • 이응직
    • KIEAE Journal
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    • 제13권5호
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    • pp.111-118
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    • 2013
  • This study aims to investigate advantages of complex installation of green roof and PV system in a public building, to analyze the impact of green roof on the efficiency of PV power generation, and to consider the correlation between green roof and PV power generation. When the temperature and power generation of the modules installed in the green roof and non-green roof of the public building were measured for 3 days, the average temperature of the green roof was 23.6 degrees, and it was 36.1 degrees in the non-green roof which increased by nearly 53%. Overall, the module temperature in the green roof was lower. On the other hand, in relation to the PV generation depending on temperature reduction during the same period, the mono-crystalline module and the poly-crystalline module in the green roof showed an increase in generation at nearly 222.2W and 341.6W, and the efficiency rose by 5.5% and 6.2%, respectively, compared to the modules in the non-green roof. Therefore, it is analyzed that green roof has a positive influence on PV power generation. Finally shows the efficiency of the installed on the Green Roof PV system (complex Installation) higher than on the concrete roof PV system. Thus, the complex PV systems as well as the usual benefits of green roofs will provide greater synergies.

간척지에서 수도 및 기타 작물의 내염성에 관한 연구 15. 간척지에 재배한 수도 엽층의 수광 효과에 미치는 염분의 영향 (Study on the Salt Tolerance of Rice and other Crops in Reclaimed Soil Areas 15. The Effects of Salt on the Efficiency of Sunlight Utilization of Rice Canopy in Reclaimed Saline Soils)

  • 임형빈
    • Journal of Plant Biology
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    • 제14권3호
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    • pp.60-65
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    • 1971
  • In order to observe the factors affecting light utilization efficiency in the canopy of a rice crop grown in reclaimed saline areas in Korea, 22 varieties of rice were cultured at the average salt concentration of 6.05mmhos/cm $25^{\circ}C$, (0.39%) in saline soils and non-saline silty loam soils. The inhibition of tillering ability by salt damage at the maximum tillering stage was greater than to growth in height. A significant direct correlation was observed between both ratios and salt concentration with each variety. In the salty areas the length of the flag leaf of the maturing stage showed a positive correlation with the production of rough rice while other living leaf showed a negative correlation. LAI of maturing stage was less in the salty area than in the non-salty area, while the former showed higher ratio in net assimilation and translocation to head with greater RGR before and after the heading stage.

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