• Title, Summary, Keyword: Least square algorithm

### Study on The Suggested Curve Fitting Algorithm for Bolt Clamping Force Measurement (볼트 체결력 측정을 위해 제안한 커브피팅 알고리즘에 관한 연구)

• Lee, Ki-Won
• Journal of Satellite, Information and Communications
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• v.7 no.3
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• pp.94-98
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• 2012
• In order to serve the exact torque clamping force, the torque measurement system use the curve fitting algorithm by the least square. The corrected least square curve fitting algorithm which suggested in this paper can surpport more exact clamping force for fastner in variable industry field using the torque. At first, This paper introduces mathematical modeling for curve fitting algorithm, and simulate it. As a result, the corrected least square algorithm have shown lower standard error value than that of the used algoritm with torque, and so this corrected least square algorithm prove high accuracy than nomal least square algorithm. The suggested algorithm will contribute to improvement of cost and safety on industry field with bolt clamping force for precision industry parts, electronics parts, aircraft, aerospace, etc.

### Interference Cancellation Methods using the CMF(Constant Modulus Fourth) Algorithm for WCDMA RF Repeater (WCDMA 무선 중계기에서 CMF 알고리즘을 이용한 간섭 제거 방식)

• Han, Yong-Sik;Yang, Woon-Geun
• Journal of IKEEE
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• v.15 no.4
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• pp.293-298
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• 2011
• In the paper, we propose a new CMF(Constant Modulus Fourth) algorithm for WCDMA(Wideband Code Multiple Access) RF(Radio Frequency) Repeater. CMF algorithm is proposed by modifying the CMA(Constant Modulus Algorithm) algorithm and improved performances are achieved by properly adjusting step size values. The steady state MSE(Mean Square Error) performance of the proposed CMF algorithm with step size of 0.35 is about 4dB better than that of the conventional CMA algorithm. And the proposed CMF algorithm requires 400~1100 less iterations than the LMS(Least Mean Square) and NLMS(Normalized Least Mean Square) algorithms at MSE of -25dB.

### Interference Cancellation System in Wireless Repeater Using Complex Signed Signed CMA Algorithm (Complex Signed-Signed CMA 알고리즘을 이용한 간섭 제거 중계기)

• Han, Yong Sik
• Journal of IKEEE
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• v.17 no.2
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• pp.145-150
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• 2013
• In the paper, we propose a new CSS(Complex Signed-Signed) CMA(Constant Modulus Algorithm) algorithm for ICS(Interference Cancellation System). When the repeater get the feedback signal, the CSS CMA algorithm is proposed at the ICS repeater using DSP(Digital Signal Processing) for the removal of interfering signals from the feedback paths. The proposed CSS CMA algorithm improved performances and hardware complexity by adjusting step size values. the steady state MSE(Mean Square Error) performance of the proposed CSS CMA algorithm with step size of 0.00043 is about 4dB better than the conventional CMA algorithm. And the proposed Complex Signed Signed CMA algorithm requires 1950 ~ 2150 less iterations than the LMS(Least Mean Square) and Signed LMS(Normalized Least Mean Square) algorithms at MSE of -25dB.

### Research on Noise Reduction Algorithm Based on Combination of LMS Filter and Spectral Subtraction

• Cao, Danyang;Chen, Zhixin;Gao, Xue
• Journal of Information Processing Systems
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• v.15 no.4
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• pp.748-764
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• 2019
• In order to deal with the filtering delay problem of least mean square adaptive filter noise reduction algorithm and music noise problem of spectral subtraction algorithm during the speech signal processing, we combine these two algorithms and propose one novel noise reduction method, showing a strong performance on par or even better than state of the art methods. We first use the least mean square algorithm to reduce the average intensity of noise, and then add spectral subtraction algorithm to reduce remaining noise again. Experiments prove that using the spectral subtraction again after the least mean square adaptive filter algorithm overcomes shortcomings which come from the former two algorithms. Also the novel method increases the signal-to-noise ratio of original speech data and improves the final noise reduction performance.

### An Adaptive Speed Estimation Method Based on a Strong Tracking Extended Kalman Filter with a Least-Square Algorithm for Induction Motors

• Yin, Zhonggang;Li, Guoyin;Du, Chao;Sun, Xiangdong;Liu, Jing;Zhong, Yanru
• Journal of Power Electronics
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• v.17 no.1
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• pp.149-160
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• 2017
• To improve the performance of sensorless induction motor (IM) drives, an adaptive speed estimation method based on a strong tracking extended Kalman filter with a least-square algorithm (LS-STEKF) for induction motors is proposed in this paper. With this method, a fading factor is introduced into the covariance matrix of the predicted state, which forces the innovation sequence orthogonal to each other and tunes the gain matrix online. In addition, the estimation error is adjusted adaptively and the mutational state is tracked fast. Simultaneously, the fading factor can be continuously self-tuned with the least-square algorithm according to the innovation sequence. The application of the least-square algorithm guarantees that the information in the innovation sequence is extracted as much as possible and as quickly as possible. Therefore, the proposed method improves the model adaptability in terms of actual systems and environmental variations, and reduces the speed estimation error. The correctness and the effectiveness of the proposed method are verified by experimental results.

### Phasor Estimation Algorithm Based on the Least Square Technique during CT Saturation

• Lee, Dong-Gyu;Kang, Sang-Hee;Nam, Soon-Ryul
• Journal of Electrical Engineering and Technology
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• v.6 no.4
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• pp.459-465
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• 2011
• A phasor estimation algorithm based on the least square curve fitting technique for the distorted secondary current due to current transformer (CT) saturation is proposed. The mathematical form of the secondary current during CT saturation is represented as the scaled primary current with magnetizing current. The information on the scaled primary current is estimated using the least square technique, with the measured secondary current in the saturated section. The proposed method can estimate the phasor of a fundamental frequency component during the saturated period. The performance of the algorithm is validated under various fault and CT conditions using a C400 CT model. A series of performance evaluations shows that the proposed phasor estimation algorithm can estimate the phasor of the fundamental frequency component with high accuracy, regardless of fault conditions and CT characteristics.

### Interference Cancellation System in Repeater Using Adaptive algorithm with step sizes (스텝사이즈에 따른 적응 알고리즘을 이용한 간섭제거 중계기)

• Han, Yong-Sik
• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.5
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• pp.549-554
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• 2014
• In the paper, we propose a new Signed LMS(Least Mean Square) algorithm for ICS(Interference Cancellation System). The proposed Signed LMS algorithm improved performances by adjusting step size values. At the convergence of 1000 iteration state, the MSE(Mean Square Error) performance of the proposed Signed LMS algorithm with step size of 0.067 is about 3 ~ 18 dB better than the conventional LMS, CMA algorithm. And the proposed Signed LMS algorithm requires 500 ~ 4000 less iterations than the and LMS and CMA algorithms at MSE of -25dB.

### Efficient Localization Algorithm for Non-Linear Least Square Estimation (비선형적 최소제곱법을 위한 효율적인 위치추정기법)

• Lee, Jung-Kyu;Kim, YoungJoon;Kim, Seong-Cheol
• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.1
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• pp.88-95
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• 2015
• This paper presents the study of the efficient localization algorithm for non-linear least square estimation. Although non-linear least square(NLS) estimation algorithms are more accurate algorithms than linear least square(LLS) estimation, NLS algorithms have more computation loads because of iterations. This study proposed the efficient algorithm which reduced complexity for small accuracy loss in NLS estimation. Simulation results show the accuracy and complexity of the localization system compared to the proposed algorithm and conventional schemes.

### Kurtosis Driven Variable Step-Size Normalized Least Mean Square Algorithm for RF Repeater

• Han, Yong-Sik;Yang, Woon-Geun
• Journal of information and communication convergence engineering
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• v.8 no.2
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• pp.159-162
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• 2010
• This paper presents a new Kurtosis driven Variable Step-Size Normalized Least Mean Square (KVSSN-LMS) algorithm to prevent repeater from oscillation due to feedback signal of radio frequency (RF) repeater. To get better Mean Square Error (MSE) performance, step-size is adjusted using the kurtosis. The proposed algorithm shows the better performance of steady state MSE. The proposed algorithm shows a better ERLE performance than that of KVSS-LMS, VSS-NLMS, NLMS algorithms.

### Multi-channel normalized FxLMS algorithm for active noise control (능동 소음 제어를 위한 정규화된 다채널 FxLMS 알고리즘)

• Chung, Ik Joo
• The Journal of the Acoustical Society of Korea
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• v.35 no.4
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• pp.280-287
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• 2016
• In this paper, we propose a normalization algorithm that can be applied to adaptive filters for multi-channel active noise control. The FxLMS (Filtered-x Least Mean Square) algorithm for the single-channel active noise control can be normalized in the same way as the NLMS (Normalized Least Mean Square) algorithm, whereas in case of the multi-channel active noise control, the single-channel normalization for the FxLMS algorithm cannot be extended to the normalization for the multi-channel FxLMS algorithm straightforwardly. First, we adopt a generalized normalization algorithm for the multi-channel FxLMS algorithm based on the principle of minimal disturbance and then, proposed a normalized algorithm considering only diagonal elements to avoid computation for matrix inversion. We carried out performance comparisons of the proposed algorithm with other algorithms without normalization. It is shown that the proposed algorithm presents better convergence characteristics under non-stationary environments.