• 제목/요약/키워드: Multiple Linear

검색결과 3,046건 처리시간 0.026초

블록암호에 대한 새로운 다중선형공격법 (New Multiple Linear Cryptanalysis of Block Ciphers)

  • 홍득조;성재철;이상진;홍석희
    • 정보보호학회논문지
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    • 제17권6호
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    • pp.11-18
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    • 2007
  • 다중선형공격은 선형공격을 강화하기 위한 방법으로 연구되어왔다. 본 논문에서는 다중선형공격에 관한 최신 이론인 Biryukov의 공격 알고리즘이 비선형 키스케줄을 가진 블록암호에 적용이 어려움을 지적하고, 새로운 다중선형공격법을 제안한다. 작은 블록암호에 대한 실험을 통하여 새로운 다중선형공격법에 관한 이론이 실제로도 매우 잘 적용될 수 있음이 보여진다.

다중적분기 사용 +1, 0, -1 계수의 선형위상 FIR 필터의 설계 (FIR Linear Phase Filter Design Using Coefficients +1,0.-1 and Multiple Integrator)

  • Kim, Hyung-Myung
    • 대한전자공학회논문지
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    • 제26권12호
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    • pp.2046-2054
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    • 1989
  • Improved algorithms are presented to design linear phase digital FIR filters with coefficients of +1,0,-1 only followed by a multiple integrator. It has been shown that the existing linear phase filter design concept for the single integrator(or, accumulator)case can be extended to the case of the multiple integrator. Linear phase conditions for the multiple integrators are summarized. Filter design methods with double or triple integrator are exploited in datail and its computer simulation results are presented to deduce the advantages of multiple integrator to the single integrator.

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다중선형회귀법을 활용한 예민화와 환경변수에 따른 AL-6XN강의 공식특성 예측 (Prediction of Pitting Corrosion Characteristics of AL-6XN Steel with Sensitization and Environmental Variables Using Multiple Linear Regression Method)

  • 정광후;김성종
    • Corrosion Science and Technology
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    • 제19권6호
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    • pp.302-309
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    • 2020
  • This study aimed to predict the pitting corrosion characteristics of AL-6XN super-austenitic steel using multiple linear regression. The variables used in the model are degree of sensitization, temperature, and pH. Experiments were designed and cyclic polarization curve tests were conducted accordingly. The data obtained from the cyclic polarization curve tests were used as training data for the multiple linear regression model. The significance of each factor in the response (critical pitting potential, repassivation potential) was analyzed. The multiple linear regression model was validated using experimental conditions that were not included in the training data. As a result, the degree of sensitization showed a greater effect than the other variables. Multiple linear regression showed poor performance for prediction of repassivation potential. On the other hand, the model showed a considerable degree of predictive performance for critical pitting potential. The coefficient of determination (R2) was 0.7745. The possibility for pitting potential prediction was confirmed using multiple linear regression.

An Approach to Applying Multiple Linear Regression Models by Interlacing Data in Classifying Similar Software

  • Lim, Hyun-il
    • Journal of Information Processing Systems
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    • 제18권2호
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    • pp.268-281
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    • 2022
  • The development of information technology is bringing many changes to everyday life, and machine learning can be used as a technique to solve a wide range of real-world problems. Analysis and utilization of data are essential processes in applying machine learning to real-world problems. As a method of processing data in machine learning, we propose an approach based on applying multiple linear regression models by interlacing data to the task of classifying similar software. Linear regression is widely used in estimation problems to model the relationship between input and output data. In our approach, multiple linear regression models are generated by training on interlaced feature data. A combination of these multiple models is then used as the prediction model for classifying similar software. Experiments are performed to evaluate the proposed approach as compared to conventional linear regression, and the experimental results show that the proposed method classifies similar software more accurately than the conventional model. We anticipate the proposed approach to be applied to various kinds of classification problems to improve the accuracy of conventional linear regression.

The relationship between the 0-tree and other trees in a linear nongroup cellular automata

  • Cho, Sung-Jin
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제5권1호
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    • pp.1-10
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    • 2001
  • We investigate the relationship between the 0-tree and other trees in linear nongroup cellular automata. And we show that given a 0-basic path of 0-tree and a nonzero attractor ${\alpha}$ of a multiple attractor linear cellulara automata with two predecessor we construct an ${\alpha}$-tree of that multiple attractor linear cellular automata.

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BLLD 부호의 Mutual Information (The Mutual Information for Bit-Linear Linear-Dispersion Codes)

  • 김향란;양재동;송경영;노종선;신동준
    • 한국통신학회논문지
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    • 제32권10A호
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    • pp.958-964
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    • 2007
  • 이 논문은 maximum a posteriori (MAP) 비트 검출(bit detection)의 비트 오류 확률 (bit error probability: BEP)과 비트 최소 평균 제곱 오류(bit minimum mean square error: bit MMSE)사이의 관계를 유도한다. BEP는 bit MMSE의 1/4 보다 크고 1/2보다 작음을 유도한다. 이 결론을 이용하면 bit-linear linear-dispersion (BLLD) 부호를 적용한 다중 입출력 (multiple-input multiple-output: MIMO) 통신 시스템에서 가우시안 채널의 mutual information의 미분 값의 하한과 상한을 BEP로부터 얻을 수 있고 나아가서 mutual information의 하한과 상한을 구할 수 있다.

다중 지역기후모델로부터 모의된 월 기온자료를 이용한 다중선형회귀모형들의 예측성능 비교 (Inter-comparison of Prediction Skills of Multiple Linear Regression Methods Using Monthly Temperature Simulated by Multi-Regional Climate Models)

  • 성민규;김찬수;서명석
    • 대기
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    • 제25권4호
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    • pp.669-683
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    • 2015
  • In this study, we investigated the prediction skills of four multiple linear regression methods for monthly air temperature over South Korea. We used simulation results from four regional climate models (RegCM4, SNURCM, WRF, and YSURSM) driven by two boundary conditions (NCEP/DOE Reanalysis 2 and ERA-Interim). We selected 15 years (1989~2003) as the training period and the last 5 years (2004~2008) as validation period. The four regression methods used in this study are as follows: 1) Homogeneous Multiple linear Regression (HMR), 2) Homogeneous Multiple linear Regression constraining the regression coefficients to be nonnegative (HMR+), 3) non-homogeneous multiple linear regression (EMOS; Ensemble Model Output Statistics), 4) EMOS with positive coefficients (EMOS+). It is same method as the third method except for constraining the coefficients to be nonnegative. The four regression methods showed similar prediction skills for the monthly air temperature over South Korea. However, the prediction skills of regression methods which don't constrain regression coefficients to be nonnegative are clearly impacted by the existence of outliers. Among the four multiple linear regression methods, HMR+ and EMOS+ methods showed the best skill during the validation period. HMR+ and EMOS+ methods showed a very similar performance in terms of the MAE and RMSE. Therefore, we recommend the HMR+ as the best method because of ease of development and applications.

통계적 방법에 근거한 AMSU-A 복사자료의 전처리 및 편향보정 (Pre-processing and Bias Correction for AMSU-A Radiance Data Based on Statistical Methods)

  • 이시혜;김상일;전형욱;김주혜;강전호
    • 대기
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    • 제24권4호
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    • pp.491-502
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    • 2014
  • As a part of the KIAPS (Korea Institute of Atmospheric Prediction Systems) Package for Observation Processing (KPOP), we have developed the modules for Advanced Microwave Sounding Unit-A (AMSU-A) pre-processing and its bias correction. The KPOP system calculates the airmass bias correction coefficients via the method of multiple linear regression in which the scan-corrected innovation and the thicknesses of 850~300, 200~50, 50~5, and 10~1 hPa are respectively used for dependent and independent variables. Among the four airmass predictors, the multicollinearity has been shown by the Variance Inflation Factor (VIF) that quantifies the severity of multicollinearity in a least square regression. To resolve the multicollinearity, we adopted simple linear regression and Principal Component Regression (PCR) to calculate the airmass bias correction coefficients and compared the results with those from the multiple linear regression. The analysis shows that the order of performances is multiple linear, principal component, and simple linear regressions. For bias correction for the AMSU-A channel 4 which is the most sensitive to the lower troposphere, the multiple linear regression with all four airmass predictors is superior to the simple linear regression with one airmass predictor of 850~300 hPa. The results of PCR with 95% accumulated variances accounted for eigenvalues showed the similar results of the multiple linear regression.

다중선형회귀분석에 의한 계절별 저수지 유입량 예측 (Forecasting of Seasonal Inflow to Reservoir Using Multiple Linear Regression)

  • 강재원
    • 한국환경과학회지
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    • 제22권8호
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    • pp.953-963
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    • 2013
  • Reliable long-term streamflow forecasting is invaluable for water resource planning and management which allocates water supply according to the demand of water users. Forecasting of seasonal inflow to Andong dam is performed and assessed using statistical methods based on hydrometeorological data. Predictors which is used to forecast seasonal inflow to Andong dam are selected from southern oscillation index, sea surface temperature, and 500 hPa geopotential height data in northern hemisphere. Predictors are selected by the following procedure. Primary predictors sets are obtained, and then final predictors are determined from the sets. The primary predictor sets for each season are identified using cross correlation and mutual information. The final predictors are identified using partial cross correlation and partial mutual information. In each season, there are three selected predictors. The values are determined using bootstrapping technique considering a specific significance level for predictor selection. Seasonal inflow forecasting is performed by multiple linear regression analysis using the selected predictors for each season, and the results of forecast using cross validation are assessed. Multiple linear regression analysis is performed using SAS. The results of multiple linear regression analysis are assessed by mean squared error and mean absolute error. And contingency table is established and assessed by Heidke skill score. The assessment reveals that the forecasts by multiple linear regression analysis are better than the reference forecasts.