Articles de revues : « Linear Sampling Method (LSM) »

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Narumanchi, Venkatalakshmi V., Fatemeh Pourahmadian, Jordan Lum, Andrew Townsend, Joseph W. Tringe, David M. Stobbe et Todd W. Murray. « Laser ultrasonic imaging of subsurface defects with the linear sampling method ». Optics Express 31, n^o 5 (24 février 2023) : 9098. http://dx.doi.org/10.1364/oe.485084.

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Laser ultrasonics is a remote nondestructive evaluation technique suitable for real-time monitoring of fabrication processes in semiconductor metrology, advanced manufacturing, and other applications where non-contact, high fidelity measurements are required. Here we investigate laser ultrasonic data processing approaches to reconstruct images of subsurface side drilled holes in aluminum alloy specimens. We demonstrate through simulation that the model-based linear sampling method (LSM) can perform accurate shape reconstruction of single and multiple holes and produce images with well-defined boundaries. We experimentally confirm that LSM produces images that represent the internal geometric features of an object, some of which may be missed by conventional imaging.

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Sun, Jiyu, et Yuhui Han. « Two-Step Extended Sampling Method for the Inverse Acoustic Source Problem ». Mathematical Problems in Engineering 2020 (7 février 2020) : 1–8. http://dx.doi.org/10.1155/2020/6434607.

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Recently, a new method, called the extended sampling method (ESM), was proposed for the inverse scattering problems. Similar to the classical linear sampling method (LSM), the ESM is simple to implement and fast. Compared to the LSM which uses full-aperture scattering data, the ESM only uses the scattering data of one incident wave. In this paper, we generalize the ESM for the inverse acoustic source problems. We show that the indicator function of ESM, which is defined using the approximated solutions of some linear ill-posed integral equations, is small when the support of the source is contained in the sampling disc and is large when the source is outside. This behavior is similar to the ESM for the inverse scattering problem. Numerical examples are presented to show the effectiveness of the method.

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Salarkaleji, Mehdi, Mohammadreza Eskandari, Jimmy Chen et Chung-Tse Wu. « Frequency and Polarization-Diversified Linear Sampling Methods for Microwave Tomography and Remote Sensing Using Electromagnetic Metamaterials ». Electronics 6, n^o 4 (18 octobre 2017) : 85. http://dx.doi.org/10.3390/electronics6040085.

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Metamaterial leaky wave antennas (MTM-LWAs), one kind of frequency scanning antennas, exhibit frequency-space mapping characteristics that can be utilized to obtain a sufficient field of view (FOV) and reconstruct shapes in both remote sensing and microwave imaging. In this article, we utilize MTM-LWAs to conduct a spectrally encoded three-dimensional (3D) microwave tomography and remote sensing that can reconstruct conductive targets with various dimensions. In this novel imaging technique, we employ the linear sampling method (LSM) as a powerful and fast reconstruction approach. Unlike the traditional LSM using only one single frequency to illuminate a fixed direction, the proposed method utilizes a frequency scanning MTM antenna array able to accomplish frequency-space mapping over the targeted 3D background that includes unknown objects. In addition, a novel technique based on a frequency and polarization hybrid method is proposed to improve the shape reconstruction resolution and stability in ill-posed inverse problems. Both simulation and experimental results demonstrate the unique advantages of the proposed LSM using MTM-LWAs with frequency and polarization diversity as an efficient 3D remote sensing and tomography scheme.

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Hossain, F., E. N. Anagnostou et K. H. Lee. « A non-linear and stochastic response surface method for Bayesian estimation of uncertainty in soil moisture simulation from a land surface model ». Nonlinear Processes in Geophysics 11, n^o 4 (24 septembre 2004) : 427–40. http://dx.doi.org/10.5194/npg-11-427-2004.

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Abstract. This study presents a simple and efficient scheme for Bayesian estimation of uncertainty in soil moisture simulation by a Land Surface Model (LSM). The scheme is assessed within a Monte Carlo (MC) simulation framework based on the Generalized Likelihood Uncertainty Estimation (GLUE) methodology. A primary limitation of using the GLUE method is the prohibitive computational burden imposed by uniform random sampling of the model's parameter distributions. Sampling is improved in the proposed scheme by stochastic modeling of the parameters' response surface that recognizes the non-linear deterministic behavior between soil moisture and land surface parameters. Uncertainty in soil moisture simulation (model output) is approximated through a Hermite polynomial chaos expansion of normal random variables that represent the model's parameter (model input) uncertainty. The unknown coefficients of the polynomial are calculated using limited number of model simulation runs. The calibrated polynomial is then used as a fast-running proxy to the slower-running LSM to predict the degree of representativeness of a randomly sampled model parameter set. An evaluation of the scheme's efficiency in sampling is made through comparison with the fully random MC sampling (the norm for GLUE) and the nearest-neighborhood sampling technique. The scheme was able to reduce computational burden of random MC sampling for GLUE in the ranges of 10%-70%. The scheme was also found to be about 10% more efficient than the nearest-neighborhood sampling method in predicting a sampled parameter set's degree of representativeness. The GLUE based on the proposed sampling scheme did not alter the essential features of the uncertainty structure in soil moisture simulation. The scheme can potentially make GLUE uncertainty estimation for any LSM more efficient as it does not impose any additional structural or distributional assumptions.

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Di Donato, Loreto, Rosa Scapaticci, Tommaso Isernia, Ilaria Catapano et Lorenzo Crocco. « An Effective Method for Borehole Imaging of Buried Tunnels ». International Journal of Antennas and Propagation 2012 (2012) : 1–9. http://dx.doi.org/10.1155/2012/246472.

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Detection and imaging of buried tunnels is a challenging problem which is relevant to both geophysical surveys and security monitoring. To comply with the need of exploring large portions of the underground, electromagnetic measurements carried out under a borehole configuration are usually exploited. Since this requires to drill holes in the soil wherein the transmitting and receiving antennas have to be positioned, low complexity of the involved apparatus is important. On the other hand, to effectively image the surveyed area, there is the need for adopting efficient and reliable imaging methods. To address these issues, in this paper we investigate the feasibility of the linear sampling method (LSM), as this inverse scattering method is capable to provide almost real-time results even when 3D images of very large domains are built, while not requiring approximations of the underlying physics. In particular, the results of the reported numerical analysis show that the LSM is capable of performing the required imaging task while using a quite simple measurement configuration consisting of two boreholes and a few number of multiview-multistatic acquisitions.

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Kuo, Yu-Hsin, et Jean-Fu Kiang. « An Iterative Approach to Improve Images of Multiple Targets and Targets with Layered or Continuous Profile ». International Journal of Microwave Science and Technology 2015 (27 septembre 2015) : 1–13. http://dx.doi.org/10.1155/2015/376374.

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An iterative approach, based on the linear sampling method (LSM) and the contrast source inversion (CSI) method, is proposed to improve the recovered images of multiple targets and targets with layered or continuous profile, including shape and distribution of electric properties. The difficulties in dealing with large targets or high contrast are partly overcome with this approach. Typical targets studied in the literatures are chosen for simulations and comparison.

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Guerriero, Vincenzo. « Maximum Likelihood Instead of Least Squares in Fracture Analysis by Means of a Simple Excel Sheet with VBA Macro ». Geosciences 13, n^o 12 (11 décembre 2023) : 379. http://dx.doi.org/10.3390/geosciences13120379.

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This technical note illustrates a linear regression algorithm based on the Maximum Likelihood Estimation (MLE), with a related Excel spreadsheet and VBA program, adapted to the case of fracture aperture data sets in which sampling of the smallest values is problematic. The method has been tested by means of Monte Carlo simulations and exhibits significantly better convergence against Least Squares criterion (LSM). As the method is conceptually simple and, following the indications illustrated here, the relative spreadsheet can be easily designed, it may be routinely used, instead of the Least Squares, in fracture analysis. Furthermore, the proposed method, with the appropriate modifications, might be potentially extended to other cases in geology and geophysics, in which significant biases at the lower limits of the sampling scale occur.

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Zeng, Pengyuan, Xuan Song, Huan Yang, Ning Wei et Liping Du. « Digital Soil Mapping of Soil Organic Matter with Deep Learning Algorithms ». ISPRS International Journal of Geo-Information 11, n^o 5 (6 mai 2022) : 299. http://dx.doi.org/10.3390/ijgi11050299.

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Digital soil mapping has emerged as a new method to describe the spatial distribution of soils economically and efficiently. In this study, a lightweight soil organic matter (SOM) mapping method based on a deep residual network, which we call LSM-ResNet, is proposed to make accurate predictions with background covariates. ResNet not only integrates spatial background information around the observed environmental covariates, but also reduces problems such as information loss, which undermines the integrity of information and reduces prediction uncertainty. To train the model, rectified linear units, mean squared error, and adaptive momentum estimation were used as the activation function, loss/cost function, and optimizer, respectively. The method was tested with Landsat5, the meteorological data from WorldClim, and the 1602 sampling points set from Xinxiang, China. The performance of the proposed LSM-ResNet was compared to a traditional machine learning algorithm, the random forest (RF) algorithm, and a training set (80%) and a test set (20%) were created to test both models. The results showed that the LSM-ResNet (RMSE = 6.40, R2 = 0.51) model outperformed the RF model in both the roots mean square error (RMSE) and coefficient of determination (R2), and the training accuracy was significantly improved compared to RF (RMSE = 6.81, R2 = 0.46). The trained LSM-ResNet model was used for SOM prediction in Xinxiang, a district of plain terrain in China. The prediction maps can be deemed an accurate reflection of the spatial variability of the SOM distribution.

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Meng, Shuo, Chen Meng, Cheng Wang et Xiang Yin. « A Method Based on Random Demodulator and Waveform Matching Dictionary to Estimate LFM Signal Parameter ». Journal of Sensors 2023 (22 mars 2023) : 1–11. http://dx.doi.org/10.1155/2023/2499336.

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The compressed sampling theory provides a good idea for sampling broadband linear frequency-modulated (LFM) signal, but the signal reconstruction after sampling should be considered when using the compressed sampling system to sample the signal. For the problem of estimating the parameters of the LFM signal under the condition of nonreconstruction, a method combining random demodulation (RD) and waveform matching (WM) dictionary is proposed in this paper. Firstly, the RD system is used to collect the compressed sampling data of LFM signal. In order to ensure the validity of the compressed sampling data, the value of the compressed sampling rate R in the RD system is discussed. Then, the feasibility of using compressed sampling data to estimate LFM signal parameters is theoretically demonstrated. According to the construction principle of waveform matching dictionary, the corresponding relationship between sparse representation coefficients, dictionary atoms, and signal parameters can be determined. Using this theory, the LFM signal parameters can be estimated. Finally, simulation and real signal experiments verify that the proposed method can realize the estimation of initial frequency and chirp rate of LFM signal when some prior information is known.

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Jia, Pengxiang, Jianhua Yang, Chengjin Wu et Miguel A. F. Sanjuán. « Amplification of the LFM signal by using piecewise vibrational methods ». Journal of Vibration and Control 25, n^o 1 (24 avril 2018) : 141–50. http://dx.doi.org/10.1177/1077546318772257.

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We propose the piecewise re-scaled vibrational resonance (VR) method and the piecewise twice sampling VR method to amplify the weak linear frequency-modulated (LFM) signal. The system used to amplify the weak LFM signal is a typical bistable system with fractional-order deflection nonlinearity. The concrete procedures of both the piecewise re-scaled VR method and the piecewise twice sampling VR method are explained in detail. Through studying the effect of the factional-order exponent on VR, we find that the traditional bistable system is not the optimal model to improve the weak LFM signal. By investigating different parameters on the VR phenomenon, we verify the effectiveness of the two proposed methods.

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Ma, Ning, et Jian Xin Wang. « Wideband LFM Signal Parameter Estimation Based on Compressed Sensing Theory ». Applied Mechanics and Materials 548-549 (avril 2014) : 1160–65. http://dx.doi.org/10.4028/www.scientific.net/amm.548-549.1160.

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Compressed sensing (CS) theory breaks through the limitations of the traditional Nyquist sampling theorem, and accomplishes the compressed sampling and reconstruction of signals based on sparsity or compressibility. In this paper, CS theory is used to do the parameter estimation of wideband Linear Frequency Modulated (LFM) signal in order to decrease the sampling pressure. A novel method that reconstructs the edge information of the LFM spectrum based on wavelet transform and CS theory is proposed. On the basis that the wideband LFM signal has approximate rectangular spectrum, the wavelet-based edge detection is introduced to provide sparse representation for the signal spectrum. The edges of the spectrum can be reconstructed by the CS reconstruction algorithms. Consequently, the initial frequency and final frequency of wideband LFM signal can be estimated with high estimation precision. The effectiveness of the proposed method is confirmed with numerical simulation.

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Yuan, Hui, Chun-yang Wang, Xin Li et Lei An. « A Method against Interrupted-Sampling Repeater Jamming Based on Energy Function Detection and Band-Pass Filtering ». International Journal of Antennas and Propagation 2017 (2017) : 1–9. http://dx.doi.org/10.1155/2017/6759169.

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Interrupted-sampling repeater jamming (ISRJ) is a new kind of coherent jamming to the large time-bandwidth linear frequency modulation (LFM) signal. Many jamming modes, such as lifelike multiple false targets and dense false targets, can be made through setting up different parameters. According to the “storage-repeater-storage-repeater” characteristics of the ISRJ and the differences in the time-frequency-energy domain between the ISRJ signal and the target echo signal, one new method based on the energy function detection and band-pass filtering is proposed to suppress the ISRJ. The methods mainly consist of two parts: extracting the signal segments without ISRJ and constructing band-pass filtering function with low sidelobe. The simulation results show that the method is effective in the ISRJ with different parameters.

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Wang, Zijian, Wenbo Yu, Zhongjun Yu, Yunhua Luo et Jiamu Li. « Neural Network-Guided Sparse Recovery for Interrupted-Sampling Repeater Jamming Suppression ». International Journal of Antennas and Propagation 2021 (2 décembre 2021) : 1–13. http://dx.doi.org/10.1155/2021/5368600.

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Interrupted-sampling repeater jamming (ISRJ) is a new type of DRFM-based jamming designed for linear frequency modulation (LFM) signals. By intercepting the radar signal slice and retransmitting it many times, ISRJ can obtain radar coherent processing gain so that multiple false target groups can be formed after pulse compression (PC). According to the distribution characteristic of the echo signal and the coherence of ISRJ to radar signal, a new method for ISRJ suppression is proposed in this study. In this method, the position of the real target is determined using a gated recurrent unit neural network (GRU-Net), and the real target can be, therefore, reconstructed by adaptive filtering in the sparse representation of the echo signal based on the target locating result. The reconstruction result contains only the real target, and the false target groups formed by ISRJ are suppressed completely. The target locating accuracy of the proposed GRU-Net can reach 92.75%. Simulations have proved the effectiveness of the proposed method.

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Lu, Lu, et Meiguo Gao. « A Truncated Matched Filter Method for Interrupted Sampling Repeater Jamming Suppression Based on Jamming Reconstruction ». Remote Sensing 14, n^o 1 (25 décembre 2021) : 97. http://dx.doi.org/10.3390/rs14010097.

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Interrupted sampling repeater jamming (ISRJ) is becoming more widely used in electronic countermeasures (ECM), thanks to the development of digital radio frequency memory (DRFM). Radar electronic counter-countermeasure (ECCM) is much more difficult when the jamming signal is coherent with the emitted signal. Due to the intermittent transmission feature of ISRJ, the energy accumulation of jamming on the matched filter shows a ‘ladder’ characteristic, whereas the real target signal is continuous. As a consequence, the time delay and distribution of the jamming slice can be obtained based on searching the truncated-matched-filter (TMF) matrix. That is composed of pulse compression (PC) results under matched filters with different lengths. Based on the above theory, this paper proposes a truncated matched filter method by the reconstruction of jamming slices to suppress ISRJ of linear frequency modulation (LFM) radars. The numerical simulations indicate the effectiveness of the proposed method and validate the theoretical analysis.

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An, Yu Yan, et Sen Sen Bai. « An Effective CS-BP Algorithm for 2-D DOA Estimation ». Applied Mechanics and Materials 128-129 (octobre 2011) : 62–65. http://dx.doi.org/10.4028/www.scientific.net/amm.128-129.62.

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The bandwidth of the direction of arrival (DOA) estimation requires high sampling rate which extends the current analog to digital converter capacity. The paper presents an effective basis pursuit (BP) algorithm based on compressive sensing (CS) signals, which is called CS-BP algorithm, for two-dimensional (2-D) DOA estimation of Linear Frequency Modulation (LFM ). The simulation results verified that the method can effectively reduce the sampling data, and improve DOA estimation performance and efficiency.

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Xiao, Jie, Xizhang Wei et Jia Sun. « Research on Interrupted Sampling Repeater Jamming Performance Based on Joint Frequency Shift/Phase Modulation ». Sensors 23, n^o 5 (4 mars 2023) : 2812. http://dx.doi.org/10.3390/s23052812.

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Interrupted sampling repeater jamming (ISRJ) is a classic active coherent jamming. Due to its structural limitations, it has inherent defects such as a discontinuous time–frequency (TF) distribution, strong distribution regularity of pulse compression results, limited jamming amplitude, and strong false targets lagging behind the real target. These defects have not been fully resolved yet due to the limitation of the theoretical analysis system. Based on the analysis of the influence factors of ISRJ on the interference performance for linear-frequency-modulated (LFM) and phase-coded signals, this paper proposes an improved ISRJ method based on the joint subsection frequency shift and two-phase modulation. The coherent superposition of jamming signals at different positions for LFM signals is achieved by controlling the frequency shift matrix and the phase modulation parameters to form a strong pre-lead false target or multiple positions and ranges of blanket jamming areas. For the phase-coded signal, the pre-lead false targets are generated through code prediction and the two-phase modulation of the code sequence, resulting in similar noise interference. The simulation results show that this method can overcome the inherent defects of ISRJ.

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Wu, Qihua, Feng Zhao, Junjie Wang, Xiaobin Liu et Shunping Xiao. « Improved ISRJ-Based Radar Target Echo Cancellation Using Frequency Shifting Modulation ». Electronics 8, n^o 1 (1 janvier 2019) : 46. http://dx.doi.org/10.3390/electronics8010046.

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Target echo cancellation is an ingenious method that protects the target of interest (TOI) from being detected by radar. Interrupted-sampling repeater jamming (ISRJ) is a novel deception jamming method for linear frequency modulation (LFM) radar countermeasures, which has been applied in target echo cancellation recently. Compared with the conventional cancellation method, not only can the target echo be successfully cancelled at radar receiver, but a train of false targets is also produced and forms deception jamming by applying the ISRJ technique. In this paper, an improved radar target echo cancellation method based on ISRJ is proposed that utilizes an extra frequency shifting modulation on the intercepted LFM radar signal. The jammer power is more efficiently utilized by the proposed method. Moreover, more flexible multi-false-target deception jamming can be obtained by adjusting the interrupted sampling frequency. The real target remains effectively protected by the false preceding target in the presence of amplitude mismatch of cancellation signal and target echo. Numerical simulations and measured data experiments are conducted to demonstrate the effectiveness of the proposed method.

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Wang, Zijian, Jiamu Li, Wenbo Yu, Yunhua Luo et Zhongjun Yu. « A Novel Interrupted-Sampling Repeater Jamming Suppression Method Based on Time-Frequency Analysis and Target Sparse Reconstruction ». International Journal of Antennas and Propagation 2022 (26 octobre 2022) : 1–17. http://dx.doi.org/10.1155/2022/2812456.

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Interrupted-sampling repeater jamming (ISRJ) is a new kind of coherent jamming for linear frequency modulation (LFM) signals. Based on digital radio frequency memory (DRFM), ISRJ can generate multiple false target groups by intercepting, storing, and retransmitting radar signal fragments, which significantly affects the postprocessing results of radar systems. Furthermore, due to the fragment interception of ISRJ, ISRJ false targets present a regular and discontinuous time-frequency (TF) distribution in contrast with real targets. Considering this intrinsic property and the coherent nature of ISRJ, this study proposes a new method based on TF analysis and target sparse reconstruction to address the ISRJ suppression issue. In this method, the echo signal is first sparsely represented to obtain both the real and false target positions. Then, according to the acquired target positions, information entropy features of targets are extracted in TF data for subsequent target identification. Finally, guided by the identification result, the real targets can be retained and reconstructed by adaptive filtering in the sparse domain to realize ISRJ suppression. Simulations have validated the effectiveness of the proposed method under various situations.

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Fang, Biao, Gao Ming Huang et Jun Gao. « Detection and Reconstruction for LFM Echo Signal Based on Blind Compressed Sensing ». Applied Mechanics and Materials 380-384 (août 2013) : 3904–7. http://dx.doi.org/10.4028/www.scientific.net/amm.380-384.3904.

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A novel framework of sub-Nyquist sampling and reconstruction for linear frequency modulation (LFM) radar echo signal based on the theory of blind compressive sensing is proposed. This mechanism takes LFM echo signals as a sparse linear combination under an unknown order p of fractional Fourier transform (FRFT) domain. Firstly, make use of good energy concentration of LFM signal in proper FRFT domain to determine the optimal order, which meets the convergence conditions. Secondly, construct DFRFT basis dictionary according to the specific sparse FRFT domain dominated by p. To reconstruct the sources, the simple orthogonal matching pursuit (OMP) is chosen with less data storage and lower computational complexity. Finally, simulations are taken on testing the proposed framework, realizing the undersampling and reconstruction without the knowledge of priori sparse basis for LFM radar echo signals, and the results are provided to verify the feasibility and efficiency of the novel method.

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Wang, Guo-hua, et Ying-bao Geng. « Fast Direct Solution of Electromagnetic Scattering from Left-Handed Materials Coated Target over Wide Angle ». Journal of Electrical and Computer Engineering 2016 (2016) : 1–7. http://dx.doi.org/10.1155/2016/2108586.

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When solving the electromagnetic scattering problems over wide angle, the traditional method of moments (MoM) needs to repeat the solving process of dense systems of linear equations using the iteration method at each incident angle, which proved to be quite inefficient. To circumvent this problem, a fast numerical method based on block LDLT factorization accelerated by adaptive cross approximation (ACA) algorithm is presented to analyze the electromagnetic scattering of left-handed materials (LHM) coated target. The ACA algorithm is applied to impedance matrix filling and all steps of block LDLT factorization process, which can accelerate the computation process and reduce the memory consumption. The numerical results proved that the proposed method is efficient in calculating monostatic RCS of LHM coated target with many required sampling angles. Compared with the traditional MoM, computation time and memory consumption are reduced effectively.

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Liu, Yifei, Yuan Zhao, Jun Zhu, Ying Xiong et Bin Tang. « Iterative High-Accuracy Parameter Estimation of Uncooperative OFDM-LFM Radar Signals Based on FrFT and Fractional Autocorrelation Interpolation ». Sensors 18, n^o 10 (19 octobre 2018) : 3550. http://dx.doi.org/10.3390/s18103550.

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To improve the parameter estimation performance of uncooperative Orthogonal Frequency Division Multi- (OFDM) Linear Frequency Modulation (LFM) radar signals, this paper proposes an iterative high-accuracy method, which is based on Fractional Fourier Transform (FrFT) and Fractional Autocorrelation (FA) interpolation. Two iterative estimators for rotation angle and center frequencies are derived from the analytical formulations of the OFDM-LFM signal. Both estimators are designed by measuring the residual terms between the quasi peak and the real peak in the fractional spectrum, which were obtained from the finite sampling data. Successful elimination of spectral leakage caused by multiple components of the OFDM-LFM signal is also proposed by a sequential removal of the strong coefficient in the fractional spectrum through an iterative process. The method flow is given and its superior performance is demonstrated by the simulation results.

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Jamila F. Kabakoran, Amelia Niwele et Sitti Zaenab. « ANALISIS KADAR VITAMIN C EKSTRAK ETANOL DAUN KELOR (Moringa Oleifera Lam) DARI DESA KAIRATU MENGGUNAKAN SPEKTROFOTOMETRI UV-VIS ». Jurnal Nurse 3, n^o 1 (14 janvier 2020) : 79–89. http://dx.doi.org/10.57213/nurse.v3i1.117.

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Moringa leaves (Moringa oleifera lam) is a type of plant from the Moringacecae tribe. Moringa leaves are found everywhere, but in the community, Moringa leaves are only used as a fence or garden barrier, but in fact Moringa leaves are one of the plants that contain lots of nutrients, both minerals and vitamins, one of which is vitamin C. The problem of this research is that many people do not knowing that Moringa leaves contain a lot of vitamin C so it is very good for consumption, especially during the COVID-19 pandemic like today. This study is a quantitative study that aims to determine the levels of vitamin C in the ethanol extract of Moringa leaves (Moringa Oleifera Lam) in Waiselang Hamlet, Kairatu Village. The sampling technique used in this research is purposive sampling. Moringa leaves were extracted using maceration method with 70% ethanol solvent for 7 days and analyzed using UV-Vis spectrophotometry at a wavelength of 560 nm. The results obtained were calculated using a linear regression equation and showed that the vitamin C content of the ethanolic extract of Moringa leaves (Moringa Oleifera Lam) in Waiselang Hamlet, Kairatu Village on average was 85.030 mg/100gr.

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Fu, Zhaopeng, Jie Jiang, Yang Gao, Brian Krienke, Meng Wang, Kaitai Zhong, Qiang Cao et al. « Wheat Growth Monitoring and Yield Estimation based on Multi-Rotor Unmanned Aerial Vehicle ». Remote Sensing 12, n^o 3 (5 février 2020) : 508. http://dx.doi.org/10.3390/rs12030508.

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Leaf area index (LAI) and leaf dry matter (LDM) are important indices of crop growth. Real-time, nondestructive monitoring of crop growth is instructive for the diagnosis of crop growth and prediction of grain yield. Unmanned aerial vehicle (UAV)-based remote sensing is widely used in precision agriculture due to its unique advantages in flexibility and resolution. This study was carried out on wheat trials treated with different nitrogen levels and seeding densities in three regions of Jiangsu Province in 2018–2019. Canopy spectral images were collected by the UAV equipped with a multi-spectral camera during key wheat growth stages. To verify the results of the UAV images, the LAI, LDM, and yield data were obtained by destructive sampling. We extracted the wheat canopy reflectance and selected the best vegetation index for monitoring growth and predicting yield. Simple linear regression (LR), multiple linear regression (MLR), stepwise multiple linear regression (SMLR), partial least squares regression (PLSR), artificial neural network (ANN), and random forest (RF) modeling methods were used to construct a model for wheat yield estimation. The results show that the multi-spectral camera mounted on the multi-rotor UAV has a broad application prospect in crop growth index monitoring and yield estimation. The vegetation index combined with the red edge band and the near-infrared band was significantly correlated with LAI and LDM. Machine learning methods (i.e., PLSR, ANN, and RF) performed better for predicting wheat yield. The RF model constructed by normalized difference vegetation index (NDVI) at the jointing stage, heading stage, flowering stage, and filling stage was the optimal wheat yield estimation model in this study, with an R2 of 0.78 and relative root mean square error (RRMSE) of 0.1030. The results provide a theoretical basis for monitoring crop growth with a multi-rotor UAV platform and explore a technical method for improving the precision of yield estimation.

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Siswanto, Siswanto, Eri Sayamar et Ahmad Rifai. « ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI KEDALAMAN JANGKAUAN (DEPTH OF OUTREACH) LEMBAGA KEUANGAN MIKRO (LKM) UED-SP DI KECAMATAN RAMBAH KABUPATEN ROKAN HULU ». Jurnal Ilmiah Pertanian 14, n^o 1 (4 avril 2018) : 21–36. http://dx.doi.org/10.31849/jip.v14i1.951.

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This study analyses the factors affecting the depth of outreach of Microfinance Institutions (MFIs) of UED-SP at Rambah Sub-district Rokan Hulu District. Factors thought to influence the depth of outreach is age of UED-SP, ROA, percent of trading sector clients, percent of agriculture sector clients and number of woman clients. The sampling method is done using by purposive sampling. This study obtained a sample of twelve UED-SPs in the village at Rambah District from in the period of 2012-2015. The data used is secondary data form pooled data. Data were obtained based on the financial reports of each of the samples. This study uses quantitative approach with analysis technique used is multiple linear regression analysis with fixed effect method of pooled data that were previously tested with the classical assumption test. Hypothesis testing using t-statistic and the F-statistic with 95% confidence level. Based on the classic assumption test found no variables that deviate. This shows that the available data has been qualified using the linear regression equation model. The results of this study show that depth of outreach are statistically significant infiuenced by age of UED-SP. However, it’s negatively affect on depth of outhreach. Whereas ROA, number of woman borrower, percent of agriculture sector clients and percent of trading sector clients has no affect on depth of outhreach. Predictive ability of these five variables on the depth of outhreach is 77,66 percent, while the 22,34 percent influenced by other factors not included in the research model.

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Raheni, Ni Putu Rika, et I. G. A. M. Asri Dwija Putri. « Pengaruh Good Governance dan Budaya Organisasi pada Kinerja Aparatur Penyelenggara Pemerintahan Desa di Kota Denpasar ». E-Jurnal Akuntansi 28, n^o 2 (8 août 2019) : 1295. http://dx.doi.org/10.24843/eja.2019.v28.i02.p19.

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This study aims to examine the effect of good governance and organizational culture on the performance of village government administrators in the city of Denpasar. The number of service villages in the city of Denpasar is 27 villages. Respondents in this study were village officials among others, Village Heads, Village Secretaries, Finance Chiefs, Village Consultative Bodies (BPD), and Community Empowerment Institutions (LPM) in each each village in the city of Denpasar. The number of samples obtained was 70 respondents using probability sampling methods with Slovin techniques. The data collection method used in this study was a questionnaire. The data analysis technique performed is the analysis of Multiple Linear Regression. Based on the analysis conducted, the results of this study indicate Good Governance and Organizational Culture have a positive effect on the Performance of Village Government Organizing Apparatus in the City of Denpasar. Keywords: Good governance, organizational culture, apparatus performance.

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Mohanan, Ezhil Pavai, John C. Panetta, Kavitha M. Lakshmi, Fouzia NA, Abhijeet Ganapule, Aby Abraham, Auro Viswabandya et al. « Pharmacokinetics of Fludarabine in Patients with Aplastic Anemia Undergoing Hematopoietic Stem Cell Transplantation ». Blood 124, n^o 21 (6 décembre 2014) : 3884. http://dx.doi.org/10.1182/blood.v124.21.3884.3884.

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Abstract Hematopoietic stem cell transplantation (HSCT) is the best treatment option for young patients with aplastic anemia. Conditioning with fludarabine (Flu) and cyclophosphamide (Cy) has been associated with improved long-term survival in patients undergoing HSCT (George et al, 2013). Graft versus host disease (GvHD), graft failure and infection associated mortality are still some of the major hurdles towards a successful outcome. Limited data available on the association between plasma Flu levels and HSCT outcome showed higher plasma Flu AUC levels to be a risk factor for non-relapse mortality. Fludarabine given intravenously as fludarabine mono-phosphate is readily converted to Flu by the enzyme ecto-5'-nucleotidase or NT5E and then is taken up into the cells by nucleoside transporters. NT5E mRNA expression and gene polymorphism in the lymphoblastoid cell lines have been shown associated with cytotoxicity to thiopurine drugs but its role on Flu pharmacokinetics (PK) is not known. We proposed to evaluate the population PK of Flu in patients with aplastic anemia undergoing HSCT and to test their influence on transplant outcome. Thirty patients diagnosed with aplastic anemia and consented to undergo HLA identical sibling HSCT using a Flu/Cy based conditioning regimen between January 2012 and February 2014 at the Department of Hematology, Christian Medical College, Vellore were included in the study (Table: Patient demographics). Pre-HSCT DNA was used to screen polymorphisms in the NT5E gene. Plasma was separated from the peripheral blood collected before (0hr) and 1,2,3,5,7 and 24 hrs after the infusion of fludarabine (30mg/m2/day x 6 days over 1 hr infusion) on days 1 and 4 and stored at -80oC until further analysis. Plasma fludarabine was analyzed using a LC-MS/MS based method and the concentration was expressed as ng/ml. Flu PK was estimated using a 2-compartment model with linear elimination. Inter-occasion variability (between dose 1, 4, 5, and 6 PK studies) on the volume (V) and elimination rate (k) was accounted for in the model. The covariates tested were: age, sex, body weight, BSA, disease type, and a polymorphism in NT5E gene. The population PK was analyzed using Monolix 4.3.2. The PK parameters AUC, CL, V and k were calculated for day 1 and day 4 of sampling. A limited sampling model (LSM) was developed with this data in order to reduce sample collection time points for future studies. The PK and PG parameters estimated are listed in Table. The influence of flu PK on clinical outcome parameters including overall survival, GvHD and rejection were estimated using Cox regression analysis. Flu PK showed wide inter-individual variation in patients with aplastic anemia receiving fludarabine based conditioning regimen (Table), which could be explained by the polymorphism in the gene converting the prodrug to active form of fludarabine. The NT5E 5’UTR variant rs2295890 was in complete linkage disequilibrium with 4 other SNPs namely: rs9450278, rs9450279, rs4599602, rs4458647 as seen both in patients and in normal healthy volunteers. Patients with variant genotype for rs2295890 showed significantly lower plasma Flu clearance compared to those with wild type genotype (p=0.0244) (Figure). Comparison of Flu PK parameters with previous studies is not possible due to heterogeneous population of patients, Flu dose and donor type included (Long Boyle et al, 2011; McCune et al, 2012). The LSM developed based on the current PK and using a D-optimality approach (via ADAPT 5) suggested a 4 time point sampling including 1 hr (end of infusion), 3, 7, and 24 hrs as a reasonable approach. This LSM will be validated by analyzing future samples. Of the 30 patients, 26 (86.6%) engrafted at a median of 14 days post BMT (range: 11-18) while 2 (6.6%) had primary graft failure and 2 died within the first 2 weeks of transplant. Grade 2-4 acute GVHD was seen in 6 (25%) with chronic GVHD in 28.5%. One patient had secondary graft failure. The Day 100 mortality was 26.6% and at present 19 (63.3%) are alive. None of the Flu PK parameters showed any significant association with engraftment, GVHD, rejection and mortality. This first study on Flu PK in a uniform cohort of patients with aplastic anemia undergoing HSCT shows that the PK of Flu is highly variable and there is genetic basis for this variation. The clinical significance of the variation in the Flu PK needs to be studied in a larger cohort of patients. Figure 1 Figure 1. Disclosures Srivastava: Octapharma: Consultancy, Other.

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Kasmini, Lili, Termala A. Barus, Muhammad A. Sarong et Miswar B. Mulya. « Hubungan panjang berat dan faktor kondisi tiram (Crassostrea gigas) di Kawasan Estuari Tibang dan Ulee Lheue, Kota Banda Aceh ». Depik 7, n^o 1 (2 mai 2018) : 60–68. http://dx.doi.org/10.13170/depik.7.1.9594.

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Study on the length-weight relationships and condition factors of oyster (Crassostrea gigas) has been done in Tibang and Ulee Lheue estuary areas, Banda Aceh for 4 months starting from July to October 2017. The objective of the study was to observe the condition of oysters in Banda Aceh City. The sampling method used line transect, where each sampling location is divided into 3 stations. Length-weight relationship analysis was performed using Linear Allometric Model (LAM). The result of the analysis of Length-weight relationship in Tibang and Ulee Lheue waters of Banda Aceh City shows the average value of 1.92 and 1.97 (negative allometric). The K value shows at Tibang location (5.07) higher than Ulee Lheue (4.98). Based on the mean value Wr indicates that Ulee Lheue (103.92) has a higher value than Tibang (102.60). The conclusion of K and Wr values shows that the environment in the research location is still stable, so it can be concluded that Tibang and Ulee Lheue waters can still support the life of oysters.Penelitian tentang hubungan panjang berat dan faktor kondisi tiram (Crassostrea gigas) telah dilakukan di kawasan estuari Tibang dan Ulee Lheue, Kota Banda Aceh selama 4 bulan dimulai dari Juli hingga Oktober 2017. Tujuan penelitian adalah untuk melihat kondisi tiram di Kota Banda Aceh. Metode pengambilan sampel dilakukan dengan transek garis, dimana pada setiap lokasi sampling dibagi atas 3 stasiun. Analisis hubungan panjang berat dilakukan menggunakan Linear Allometric Model (LAM). Hasil analisis hubungan panjang berat di perairan Tibang dan Ulee Lheue Kota Banda Aceh menunjukkan nilai b rerata 1,92 dan 1,97 (alometrik negatif). Adapun nilai K menunjukkan rerata pada lokasi Tibang (5,07) lebih tinggi berbanding Ulee Lheue (4,98). Berdasarkan nilai rata-rata Wr menunjukkan bahwa perairan Ulee Lheue (103,92) memiliki nilai lebih tingi bebanding perairan Tibang (102,60). Adapun kesimpulan nilai K dan Wr menunjukkan keadaan lingkungan pada lokasi penelitian masih dalam keadaan stabil, sehingga dapat disimpulkan perairan Tibang dan Ulee Lheue masih dapat mendukung kehidupan tiram.

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Machrizal, Rusdi, Khairul Khairul, Juliana Nasution, Rivo H. Dimenta et Arman Harahap. « Distribution and length-weight relationships of Hilsa shad Tenualosa ilisha in the Bilah River, Labuhanbatu Regency, North Sumatera Province, Indonesia ». Aceh Journal of Animal Science 4, n^o 1 (11 juillet 2019) : 42–49. http://dx.doi.org/10.13170/ajas.4.1.13799.

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Hilsa shad Tenualosa ilishais of the indigenous fish species and the icon of the Labuhanbatu Regency, Indonesia. Presently, a very limited study was done in this species. Hence, the purpose of this study was to analyse the distribution and growth patterns based on the length-weight relationship of Hilsa shad T. ilishaon Bilah River, Labuhanbatu District, Sumatera Utara Province, Indonesia. Sampling was carried out for 3 months starting in February-April 2019 with the exploration method. Determination of sampling locations based on information from local fishermen. Analysis of distribution data used the Morisita index and growth patterns used the Linear Allometric Model (LAM). The analysis results of Hilsa shad distribution indicated that these fish were distributed in groups/clustered with the Morisita index value of 2.211-2.314. The growth pattern of the fish was negative allometric with a value of b3. Correlation analysis showed that DO was closely related to distribution (r2=0.661), meanwhile, light penetration was closely related to growth patterns (r2=0.914). It is concluded that the distribution of Hilsa shad fish in the Bilah River was in groups or clustered, with a negative allometric growth pattern. Keywords: Hilsa Shad, distribution, growth pattern, Tenualosa ilisha

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Ebel, Horst. « Quantitative analysis by X-ray induced total electron yield (TEY) compared to XRFA ». Powder Diffraction 19, n^o 1 (mars 2004) : 90–96. http://dx.doi.org/10.1154/1.1649329.

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The theoretical concepts of the two methods are similar. Consequently, comparable fundamental parameter algorithms can be developed and applied to a quantitative analysis of bulk specimens and to an investigation of thin layers by TEY and by XRFA. Whereas the sampling depth of XRFA is determined by photoelectric absorption, for TEY the escape probability of electrons reduces this quantity to values of less than 100 nm. Thus, TEY is practically a surface analytical method with sampling depths between X-ray photoelectron spectrometry and XRFA. The decrease of fluorescence yields with decreasing atomic number Z is responsible for a significant reduction of the elemental sensitivity of XRFA in the range of low-Z elements. On the other hand, the elemental sensitivity of TEY increases with decreasing Z as a consequence of the dominating contribution of KLL- and LMM-Auger electrons to measured TEY jumps. The possibility to quantify submonolayers and layers of nm thickness buried under nm layers, a nearly linear dependence of TEY signals versus the elemental concentration of multielement specimens and the EXAFS and XANES information that is contained in measured TEY responses, are valuable features of TEY. A disadvantage of TEY is the time consuming sequential data accumulation of TEY spectra when compared to energy dispersive XRFA. But due to progress in instrumentation TEY is no longer reserved to synchrotron radiation sources

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Hasibuan, Maslimah, et Rusdi Machrizal. « Faktor Kondisi dan Pola Pertumbuhan Oxygaster anomalura ». BIOEDUSAINS:Jurnal Pendidikan Biologi dan Sains 4, n^o 1 (28 juin 2021) : 112–16. http://dx.doi.org/10.31539/bioedusains.v4i1.2306.

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This study aims to obtain information related to the biological and ecological aspects of the Oxygaster anomalura in the Mailil River, Bandar Kumbul Village. The method used in this research is exploratory. Sampling was done using a fishing rod. The growth pattern was calculated using the length-weight relationship using the Linear Allometric Model (LAM), while the condition factor used the Fulton formula (K) and relative weight (Wr). The results showed that as many as 30 samples of Sulum Fish (Oxygaster anomalura) were caught during the study. Analysis of the length-weight relationship showed a negative allometric relationship with a value of b=1.94 (b>3). The Fulton condition factor (K) value is 1,195, while the value of the relative condition factor (Wr) is 169.42. In conclusion, the Mailil River as an ecosystem and habitat for O. anomalura fish is balanced. Keywords: Condition Factor, Oxygaster anomalura, Mailil River

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Merawati, Luh Komang, Ni Kadek Hariani et Ida Ayu Nyoman Yuliastuti. « Kompetensi dan Peran Partisipasi Masyarakat dalam Mewujudkan Akuntabilitas Pengelolaan Dana Desa ». Substansi : Sumber Artikel Akuntansi Auditing dan Keuangan Vokasi 6, n^o 1 (16 décembre 2022) : 78–99. http://dx.doi.org/10.35837/subs.v6i1.1765.

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This study aims to examine and obtain empirical evidence the effect of village apparatus competency, head village leadership, community participation, utilization of informaton technology and internal control system in accountability of village fund management. The population in this study were 8 villages in Kecamatan Selat, Kabupaten Karangasem, using purposive sampling method, a sample of 44 respondents was obtained consist of the village secretary, head of planning affairs, head of financial affairs, head of BPD, chair of LPM, and head of PKK. The research methodology used is quantitative using multiple linear regression analysis. The results of this study indicate that the variable village apparatus competency, head village leadership, and utilization of information technology have no significant effect on accountability of village fund management, community participation has positive effect on accountability of village fund management, while internal control system has negative effect on accountability of village fund management.

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Kaliuzhnyi, Mykola. « Generalizing the sampling theorem for a frequency-time domain to sample signals under the conditions of a priori uncertainty ». Eastern-European Journal of Enterprise Technologies 3, n^o 9(111) (25 juin 2021) : 6–15. http://dx.doi.org/10.15587/1729-4061.2021.235844.

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The radio monitoring of radiation and interference with electronic means is characterized by the issue related to the structural-parametric a priori uncertainty about the type and parameters of the ensemble of signals by radio-emitting sources. Given this, it is a relevant task to devise a technique for the mathematical notation of signals in order to implement their processing, overcoming their a priori uncertainty in terms of form and parameters. A given problem has been solved by the method of generalization and proof for the finite signals of the Whittaker-Kotelnikov-Shannon sampling theorem (WKS) in the frequency-time domain. The result of proving it is a new discrete frequency-temporal description of an arbitrary finite signal in the form of expansion into a double series on the orthogonal functions such as sinx/x, or rectangular Woodward strobe functions, with an explicit form of the phase-frequency-temporal modulation function. The properties of the sampling theorem in the frequency-time domain have been substantiated. These properties establish that the basis of the frequency-time representation is orthogonal, the accuracy of approximation by the basic functions sinx/x and rectangular Woodward strobe functions are the same, and correspond to the accuracy of the UCS theorem approximation, while the number of reference points of an arbitrary, limited in the width of the spectrum and duration, signal, now taken by frequency and time, is determined by the signal base. The devised description of signals in the frequency-time domain has been experimentally investigated using the detection-recovery of continuous, simple pulse, and linear-frequency-modulated (LFM) radio signals. The constructive nature of the resulting description has been confirmed, which is important and useful when devising methods, procedures, and algorithms for processing signals under the conditions of structural-parametric a priori uncertainty.

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Batubara, A. S., Z. A. Muchlisin, D. Efizon, R. Elvyra et M. Irham. « Length-Weight Relationships and Condition Factors of the Naleh Fish, Barbonymus gonionotus (Pisces, Cyprinidae) Harvested from Nagan Raya Waters, Indonesia ». Vestnik Zoologii 53, n^o 1 (1 février 2019) : 75–82. http://dx.doi.org/10.2478/vzoo-2019-0008.

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Abstract The objective of the present study was to examine the growth pattern and condition factors of the naleh fish, Barbonymus gonionotus Bleeker, 1849 in Nagan River, Nagan Raya District, Aceh Province, Indonesia. The sampling was conducted for 12 months from January 2016 to December 2016 using the explorative survey method. The sampling locations were determined based on the information given by local fishermen. A total of 761 fish samples were collected during the study. The Linear Allometric Model (LAM), Fulton’s and Relative Weight conditions factors were utilized to analyze the length-weight relationship and condition factor of the fish using growth parameters. The results showed that the highest coefficient of b was recorded in December, where the b value of males were 3.82 and 4.23 for the females with the average b value of males and females were 2.92 indicating an isometric growth pattern. The average Fulton’s condition factor (K) was 2.28 and the average Relative weight (Wr) condition factor was 100.59. It is concluded that fish had the isometric growth pattern and based on K and Wr value, the result implies that the waters are still in a good condition. Furthermore, the availability of food sources, low competitors, and low predators indicate that the aquatic environment is in a stable condition.

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Dwirastina, Mirna, et Marson. « Length-weight relationships Silver barb (Barbonymus gonionotus) in Mamberamo River, Papua ». E3S Web of Conferences 322 (2021) : 01024. http://dx.doi.org/10.1051/e3sconf/202132201024.

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There are big rivers in Papua province, one of which is the Mamberamo River. The Mamberamo River, known as the Amazon of Indonesia, has very high biodiversity. Silver barb is one of the fish caught in the Mamberamo River. Silver barb is an adaptable fish, has many types and varies. Variations in Silver barb are caused by interactions with the environment as well as isolation mechanisms. This research explains the relationship between weight-length and condition factors Silver barb in Mamberamo River, Papua. The research location consists of four observation stations: Kali Merah, Kerumi, Telaga, and Sungai Putus. Sampling was carried out in February, May, August, and October 2016. The research method used was a survey using an enumerator and analysis using the LAM (linear allometric) model. The results showed that Silver barb growth was allometric negative in February and October, but in May and August, growth was allometric positive. The factor conditions for the Silver barb range 1.014-1.02.

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Rifai, Ahmad, Siswanto Siswanto et Eri Sayamar. « ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI KEDALAMAN JANGKAUAN (DEPTH OF OUTREACH) LEMBAGA KEUANGAN MIKRO (LKM) UED-SP DI KECAMATAN RAMBAH KABUPATEN ROKAN HULU ». SEPA : Jurnal Sosial Ekonomi Pertanian dan Agribisnis 14, n^o 1 (15 mai 2018) : 77. http://dx.doi.org/10.20961/sepa.v14i1.21052.

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Abstract : This study analysis the factors affecting the depth of outreach of Microfinance Institutions (MFIs) of UED-SP at Rambah Sub-district Rokan Hulu District. Factors thought to influence the depth of outreach is age of UED-SP, ROA, percent of trading sector clients, percent of agriculture sector clients and number of woman clients. The sampling method is done using by purposive sampling. This study obtained a sample of twelve UED-SPs in the village at Rambah District from in the period of 2012-2015. The data used is secondary data form pooled data. Data were obtained based on the financial reports of each of the samples. This study uses quantitative approach with analysis technique used is multiple linear regression analysis with fixed effect model of pooled data that were previously tested with the classical assumption test. Hypothesis testing using t-statistic and the F-statistic with 95% confidence level. Based on the classic assumption test found no variables that deviate. This shows that the available data has been qualified using the linear regression equation model. The results of this study show that depth of outreach are statistically significant infiuenced by age of UED-SP. However, it’s negatively affect on depth of outhreach. Whereas ROA, number of woman borrower, percent of agriculture sector clients and percent of trading sector clients has no affect on depth of outhreach. Predictive ability of these five variables on the depth of outhreach is 77,66 percent, while the 22,34 percent influenced by other factors not included in the research model. Abstrak : Penelitian ini bertujuan untuk menguji faktor-faktor yang mempengaruhi kedalaman jangkauan (Depth of Outrech) pada LKM UED-SP di Kecamatan Rambah Kabupaten Rokan Hulu. Faktor-faktor yang diduga berpengaruh terhadap kedalaman jangkauan adalah umur UED-SP, rasio pengembalian aset (ROA), jumlah peminjam wanita, proporsi peminjam sektor pertanian dan proporsi peminjam sektor perdagangan. Metode pengambilan sampel dilakukan dengan menggunakan purposive sampling. Dalam penelitian ini diperoleh sampel sebanyak 12 LKM UED-SP di Desa/Kelurahan yang ada di Kecamatan Rambah dan data yang dihimpun adalah 4 tahun dari tahun 2012-2015. Data yang digunakan adalah data sekunder data panel. Data diperoleh berdasarkan laporan keuangan dari masing-masing sampel. Teknik analisis yang digunakan adalah analisis regresi linear berganda data panel dengan model Fixed Effect (FEM) yang sebelumnya diuji dengan uji asumsi klasik. Uji hipotesis menggunakan t-statistik serta F-statistik dengan tingkat kepercayaan 95%. Berdasarkan uji asumsi klasik tidak ditemukan variabel yang menyimpang. Hal ini menunjukkan bahwa data yang tersedia telah memenuhi syarat menggunakan model persamaan linear berganda. Hasil penelitian menunjukkan bahwa variabel umur UEDSP berpengaruh signifikan terhadap kedalaman jangkauan. Namun berpengaruh negatif terhadap kedalaman jangkauan. Kemampuan prediksi kelima variabel tersebut terhadap kedalaman jangkauan adalah 77,66 persen, sedangakan 22,34 persen dipengaruhi oleh faktor lain yang tidak dimasukkan ke dalam model penelitian.

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Yuanita, Poppy, et Yeremias Torontuan Keban. « Evaluasi Efektivitas Program Kang Pisman di Kelurahan Sukaluyu dan Faktor yang Mempengaruhinya ». Jurnal Rekayasa Hijau 4, n^o 2 (7 août 2020) : 93–108. http://dx.doi.org/10.26760/jrh.v4i2.46-61.

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ABSTRAKPengelolaan sampah telah menjadi salah satu permasalahan yang jamak terjadi di perkotaan. Produksi sampah meningkat seiring dengan pertambahan penduduk dan jumlah konsumsi serta gaya hidup masyarakat, namun tidak diimbangi dengan pengelolaan sampah yang ramah lingkungan dan berkelanjutan. Untuk itu, diperlukan upaya untuk mulai mengurangi, memisahkan, dan memanfaatkan sampah. Program Kang Pisman adalah konsep yang diperkenalkan oleh Pemerintah Kota Bandung untuk mengatasi masalah tersebut.Tujuan dari penelitian ini adalah mengevaluasi efektivitas Program Kang Pisman dan mengetahui faktor yang memepengaruhinya. Evaluasi efektivitas perlu dilakukan untuk mengetahui apakah hasil dari program tersebut sudah sesuai dengan tujuan awal perencanaan. Metode dalam penelitian ini adalah deskriptif kuantitatif dengan menggunakan instrumen pengumpulan data berupa kuesioner terhadap 98 rumah yang menjadi sampel penelitian. Efektivitas Program Kang Pisman penting untuk diteliti begitu juga faktor yang berpengaruh terhadap program tersebut agar dapat digunakan sebagai bahan evaluasi program dan menjadi masukan dalam membuat kebijakan lebih lanjut tentang pelaksanaan program. Hasil skoring variabel efektivitas menunjukkan bahwa Program Kang Pisman ada pada tingkatan cukup efektif. Untuk mengetahui faktor yang mempengaruhi efektivitas program, dilakukan analisis regresi linear berganda dengan enam variabel bebas, yaitu komitmen pemerintah, kemudahan menjalankan program, kinerja petugas pelaksana, ketersediaan sarana dan prasarana, peran Lembaga Swadaya Masyarakat (LSM) dan persepsi masyarakat. Faktoryang berpengaruh signifikan terhadap efektivitas adalah persepsi masyarakat dan kemudahan dalam menjalankan program.Kata kunci: evaluasi efektivitas, kang pisman, pengelolaan sampah. ABSTRACTSolid waste management is one of the global problems faced by urban areas. Waste generation increased according to population growth and followed by consumption and lifestyle, however not balanced with the management of waste that is environmentally friendly and sustainable. We need to reduce, sort, and reuse the waste. The Kang Pisman Program is a concept introduced by the Bandung City Government to overcome this problem. The objectives of this research are to evaluate the effectiveness of the program and its influential driving factors. Evaluation of effectiveness needs to be held to find out wheater the results of the program are following the original purpose. This research uses a quantitative descriptive method with a questionnaire instrument to interview 98 houses as a sampling. The effectiveness of the Kang Pisman Program is essential to evaluate as well as the factors that influence the program so that it can be used as a program evaluation material and be input in making further policy regarding program implementation. The scoring result shows that Kang Pisman Program is at quite effective level. To find out the factors that influence the effectiveness of the program, multiple linear regression analysis was carried out with six independent variabels, namely goverment commitment, ease of running the program, the staff performance, infrastructure, the role of NGOs and community perceptions. Factors that have a significant influence on effectiveness are community perception and ease in running the program.Keywords: effectiveness evaluation, kang pisman, waste management.

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Yuanita, Poppy, et Yeremias Torontuan Keban. « Evaluasi Efektivitas Program Kang Pisman di Kelurahan Sukaluyu dan Faktor yang Mempengaruhinya ». Jurnal Rekayasa Hijau 4, n^o 2 (7 août 2020) : 93–108. http://dx.doi.org/10.26760/jrh.v4i2.93-108.

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ABSTRAKPengelolaan sampah telah menjadi salah satu permasalahan yang jamak terjadi di perkotaan. Produksi sampah meningkat seiring dengan pertambahan penduduk dan jumlah konsumsi serta gaya hidup masyarakat, namun tidak diimbangi dengan pengelolaan sampah yang ramah lingkungan dan berkelanjutan. Untuk itu, diperlukan upaya untuk mulai mengurangi, memisahkan, dan memanfaatkan sampah. Program Kang Pisman adalah konsep yang diperkenalkan oleh Pemerintah Kota Bandung untuk mengatasi masalah tersebut.Tujuan dari penelitian ini adalah mengevaluasi efektivitas Program Kang Pisman dan mengetahui faktor yang memepengaruhinya. Evaluasi efektivitas perlu dilakukan untuk mengetahui apakah hasil dari program tersebut sudah sesuai dengan tujuan awal perencanaan. Metode dalam penelitian ini adalah deskriptif kuantitatif dengan menggunakan instrumen pengumpulan data berupa kuesioner terhadap 98 rumah yang menjadi sampel penelitian. Efektivitas Program Kang Pisman penting untuk diteliti begitu juga faktor yang berpengaruh terhadap program tersebut agar dapat digunakan sebagai bahan evaluasi program dan menjadi masukan dalam membuat kebijakan lebih lanjut tentang pelaksanaan program. Hasil skoring variabel efektivitas menunjukkan bahwa Program Kang Pisman ada pada tingkatan cukup efektif. Untuk mengetahui faktor yang mempengaruhi efektivitas program, dilakukan analisis regresi linear berganda dengan enam variabel bebas, yaitu komitmen pemerintah, kemudahan menjalankan program, kinerja petugas pelaksana, ketersediaan sarana dan prasarana, peran Lembaga Swadaya Masyarakat (LSM) dan persepsi masyarakat. Faktoryang berpengaruh signifikan terhadap efektivitas adalah persepsi masyarakat dan kemudahan dalam menjalankan program.Kata kunci: evaluasi efektivitas, kang pisman, pengelolaan sampah. ABSTRACTSolid waste management is one of the global problems faced by urban areas. Waste generation increased according to population growth and followed by consumption and lifestyle, however not balanced with the management of waste that is environmentally friendly and sustainable. We need to reduce, sort, and reuse the waste. The Kang Pisman Program is a concept introduced by the Bandung City Government to overcome this problem. The objectives of this research are to evaluate the effectiveness of the program and its influential driving factors. Evaluation of effectiveness needs to be held to find out wheater the results of the program are following the original purpose. This research uses a quantitative descriptive method with a questionnaire instrument to interview 98 houses as a sampling. The effectiveness of the Kang Pisman Program is essential to evaluate as well as the factors that influence the program so that it can be used as a program evaluation material and be input in making further policy regarding program implementation. The scoring result shows that Kang Pisman Program is at quite effective level. To find out the factors that influence the effectiveness of the program, multiple linear regression analysis was carried out with six independent variabels, namely goverment commitment, ease of running the program, the staff performance, infrastructure, the role of NGOs and community perceptions. Factors that have a significant influence on effectiveness are community perception and ease in running the program.Keywords: effectiveness evaluation, kang pisman, waste management.

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Lin, Yaolin, Luqi Zhao, Xiaohong Liu, Wei Yang, Xiaoli Hao et Lin Tian. « Design Optimization of a Passive Building with Green Roof through Machine Learning and Group Intelligent Algorithm ». Buildings 11, n^o 5 (2 mai 2021) : 192. http://dx.doi.org/10.3390/buildings11050192.

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This paper proposed an optimization method to minimize the building energy consumption and visual discomfort for a passive building in Shanghai, China. A total of 35 design parameters relating to building form, envelope properties, thermostat settings, and green roof configurations were considered. First, the Latin hypercube sampling method (LHSM) was used to generate a set of design samples, and the energy consumption and visual discomfort of the samples were obtained through computer simulation and calculation. Second, four machine learning prediction models, including stepwise linear regression (SLR), back-propagation neural networks (BPNN), support vector machine (SVM), and random forest (RF) models, were developed. It was found that the BPNN model performed the best, with average absolute relative errors of 3.27% and 1.25% for energy consumption and visual comfort, respectively. Third, six optimization algorithms were selected to couple with the BPNN models to find the optimal design solutions. The multi-objective ant lion optimization (MOALO) algorithm was found to be the best algorithm. Finally, optimization with different groups of design variables was conducted by using the MOALO algorithm with the associated outcomes being analyzed. Compared with the reference building, the optimal solutions helped reduce energy consumption up to 34.8% and improved visual discomfort up to 100%.

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Lum, Bert L., Kevin J. Lane, Timothy W. Synold, Adrian Goram, Steven B. Charnick et Branimir I. Sikic. « Validation of a Limited Sampling Model to Determine Etoposide Area Under the Curve ». Pharmacotherapy : The Journal of Human Pharmacology and Drug Therapy 17, n^o 5 (10 septembre 1997) : 887–90. http://dx.doi.org/10.1002/j.1875-9114.1997.tb03779.x.

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Study Objective. To validate the utility of a previously reported 3‐point limited sampling model (LSM) for determining etoposide area under the curve to infinity (AUC∞).Design. Secondary analysis of data from two clinical trials of etoposide.Setting. University medical center clinical research center.Patients. Thirty‐four patients with different malignancies.Interventions. Etoposide was administered as a 2‐hour infusion to 34 patients. Serial plasma samples were drawn over 24 hours after the infusion and analyzed for etoposide by high‐performance liquid chromatography.Measurements and Main Results. The 3‐point LSM AUC was compared with a 14‐point actual AUC calculated by the linear trapezoidal rule. Actual and predicted AUC∞ by the LSM were highly correlated (r=0.97, p<0.0001). The LSM predictions had a mean absolute error of 10.9% (95% CI −14.1, −5.3) and a mean error of −9.7% (95% CI 6.9, 14.9). Nine patients with poor AUC∞ estimations by the LSM (error > 12%) tended to have abnormally low or high peak concentrations.Conclusion. Our findings suggest the development of more robust LSM using other techniques, such as pharmacostatistical models, that can accommodate a greater degree of pharmacokinetic variability. (Pharmacotherapy 1997;17(5):887–890)

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Ramani, Prasanna Venkatesan, Ponnambalam Selvaraj, Shanmugapriya T. et Anshul Gupta. « Application of Linear Scheduling in Water Canal Construction with a Comparison of Critical Path Method ». Journal of Construction in Developing Countries 27, n^o 1 (juin 2022) : 189–212. http://dx.doi.org/10.21315/jcdc2022.27.1.11.

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Critical path method (CPM) still remains the most commonly used scheduling technique, despite many studies confirming its shortcomings for scheduling repetitive construction projects. This research evaluated the case study of an alignment-based precast water canal erection project, which was originally planned with CPM and analysed the suitability of using linear scheduling method (LSM) for the same project. The case study project was scheduled using both CPM and LSM tools and the results were compared in terms of estimated total duration and resource cost. The results showed that LSM produced a saving of 10 days in total duration and 20.07% in estimated resource cost over CPM. LSM also proved to be the better tool in terms of other schedule attributes like resource assignment, levelling, visualisation, etc., for alignment-based projects. LSM can be highly efficient for scheduling different types of repetitive construction and offers benefits like better workflow and continuous resource usage.

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Suryadharma, Arthur. « PEMBUATAN SOFTWARE SEBAGAI APLIKASI LINEAR SCHEDULING METHOD PADA PERENCANAAN PENJADWALAN PROYEK JALAN ». Dimensi Utama Teknik Sipil 4, n^o 1 (1 février 2017) : 1–8. http://dx.doi.org/10.9744/duts.4.1.1-8.

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Proyek konstruksi jalan adalah contoh dari proyek linear, dimana terdiri aktivitas – aktivitas yang berulang dari unit yang satu ke unit berikut. Oleh karena itu tipe proyek ini butuh perencanaan penjadwalan yang tepat. Linear Scheduling Method (LSM) adalah teknik penjadwalan yang tepat untuk menjadwalkan unit – unit aktivitas proyek linear secara berkesinambungan sehingga terhindar dari idle time. Pada penelitian ini dilakukan pembuatan software LSM yang dapat menjaga kesinambungan kelompok kerja, disamping itu dapat menjadwalkan aktivitas – aktivitas agar terjadwal berdasarkan urutan yang ditentukan. Studi kasus proyek jalan digunakan pada penelitian ini untuk menguji software yang dibuat. Pembuatan software LSM menggunakan bantuan Visual Basic Software pada Microsoft Excel. Software yang diimplementasi pada proyek jalan menunjukkan kemampuan software yang dibuat untuk menghasilkan durasi proyek tanpa adanya idle time pada perpindahan kelompok kerja dan menjaga hubungan ketergantungan antar aktivitas.

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Xiong, Yibing, Yi Zhou, Futao Wang, Shixin Wang, Zhenqing Wang, Jianwan Ji, Jingming Wang, Weijie Zou, Di You et Gang Qin. « A Novel Intelligent Method Based on the Gaussian Heatmap Sampling Technique and Convolutional Neural Network for Landslide Susceptibility Mapping ». Remote Sensing 14, n^o 12 (15 juin 2022) : 2866. http://dx.doi.org/10.3390/rs14122866.

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Landslide susceptibility mapping (LSM) is significant for disaster prevention and mitigation, land use management, and as a reference for decision-making. Convolutional neural networks (CNNs) in deep learning have been successfully applied to LSM studies and have been shown to improve the accuracy of LSM. Although optimizing the quality of negative samples at the input step of a deep learning model can improve the accuracy of the model, the risk of model overfitting may increase. In this study, an LSM method based on the Gaussian heatmap sampling technique and a CNN was developed from the perspective of LSM dataset sampling. A Gaussian heatmap sampling technique was used to enrich the variety of landslide inventory at the input step of the deep learning model to improve the accuracy of the LSM results. This sampling technique involved the construction of a landslide susceptibility Gaussian heatmap neural network model, LSGH-Net, by combining a CNN. A series of optimization strategies such as attention mechanism, dropout, etc., were applied to improve the model structure and training process. The results demonstrated that the proposed approach outperformed the benchmark CNN-based algorithm in terms of metrics (Accuracy = 95.30%, F1 score = 95.13%, and Sensitivity = 91.79%). The Gaussian heatmap sampling technique effectively improved the accuracy of frequency histograms of the landslide susceptibility index, which provided finer-grained mapping details and more reasonable landslide density. By analyzing Gaussian heatmap at different scales, the approach proposed in this paper is an important reference for different regions and other disaster susceptibility studies as well.

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Douglas, Steve, et Hollie Raynor. « Differences in Body Mass Index Z-Scores Among Children and Adolescent Participants of NHANES 2003–2016 with Different Temporal Eating Patterns ». Current Developments in Nutrition 4, Supplement_2 (29 mai 2020) : 586. http://dx.doi.org/10.1093/cdn/nzaa047_006.

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Abstract Objectives To determine if body mass index z-scores (zBMI) differ among children and adolescents who reported an early temporal eating pattern when compared to those who reported other temporal eating patterns. Methods Data from children (6–12 years) and adolescents (13–19 years) participating in the National Health and Nutrition Examination Survey 2003–2016 were used. Children and adolescents were analyzed separately because of the phase delay in circadian rhythms experienced during adolescence. Energy intake and timing of intake was assessed using two 24-hour dietary recalls. Children (n = 2,565) and adolescents (n = 2,321) were included if they reported plausible intakes (≥500 kcals/day) with the same temporal eating patterns on both days. Temporal eating patterns were defined by the following morning and evening parameters: consumed 20% of total caloric intake before 10 AM (EAM); didn't consume 20% before 10 AM (LAM); consumed at least 80% of total caloric intake before 7 PM (EPM); didn't consume 80% before 7 PM (LPM). These parameters provided four temporal eating patterns: EAM-EPM, EAM-LPM, LAM-EPM, LAM-LPM. A covariate adjusted general linear models, adjusted for the complex sampling design, was used to compare zBMI of those participating in the different patterns. Data are reported as means ± SEM and P < 0.0125 was considered significant. Results zBMI for EAM-EPM (n = 887; 0.460 ± 0.037) children was lower when compared to LAM-LPM (n = 455; 0.641 ± 0.056; P = 0.007) children. For adolescents, zBMI for EAM-EPM (n = 445; 0.516 ± 0.048; P = 0.005), EAM-LPM (n = 172; 0.370 ± 0.089; P = 0.001), and LAM-LPM (n = 839; 0.549 ± 0.039; P = 0.011) adolescents were lower when compared to LAM-EPM (n = 1,097; 0.683 ± 0.035) adolescents. No other differences were observed. Conclusions Children between the ages of 6 and 12 who reported consuming an early eating pattern have a lower zBMI when compared to those who reported consuming a later eating pattern. Adolescents who didn't consume 20% of their total energy intake before 10 am and did consume more than 80% of their total intake before 7 pm have a greater zBMI than their peers who consistently reported consuming alternative eating patterns. Funding Sources None

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Wan, Xiang Kui, Kang Hui Yan et Ming Gui Li. « Detecting and Quantifying T Wave Alternans Using Linear Least Squares Curve Fitting Method ». Applied Mechanics and Materials 239-240 (décembre 2012) : 1404–8. http://dx.doi.org/10.4028/www.scientific.net/amm.239-240.1404.

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Evaluatement of T-wave alternans (TWA) is a non-invasive method to identify patients at risk for sudden cardiac death. A novel time-domain algorithm based on linear least squares method (LSM) for TWA analysis is developed in this paper. And the LSM’s ability to TWA analaysis in comparison with the modified moving average (MMA) method was demonstrated. In a simulation study LSM and MMA can both detected TWA with high accuracy, but under lower SNR levels LSM was found more robust, and its evaluated TWA values are closer to true TWA value. The algorithm was subsequently used to analyze the clinical ECGs from T-Wave Alternans Challenge Database, which showed that the results from this method vs. MMA had the correlation coefficients of 0.89.

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Sirathanakul, Sirin, et Tanatta Amnuywattanakul. « The E-Learning on Analysis of the Experimental Results by Using Graphs ». Applied Mechanics and Materials 804 (octobre 2015) : 355–58. http://dx.doi.org/10.4028/www.scientific.net/amm.804.355.

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E-learning is a popular technique that can solve learning problems of student. In this study, the learning package of data analysis by using graphing paper to attain linear relationship between independent and dependent variables was invented and utilized. The learning package, consisting of contents and answer key video made from Power Point was converted to video format. The samples were 58 students of Bachelor of Science program who were selected by multi-stage sampling and divided into experimental and control groups. The experimental group composed of 29 students, learnt by using e-learning via LMS Moodle at RMUTP website. The control group, 29 students, was performed by a conventional technique through multimedia teaching with PowerPoint. The research tools consisted of the lesson of graphical analysis, the questionnaire for quality evaluation of the lesson and the achievement evaluation. The results were found that the quality of research tools was very good and the average value of learning achievement of the experimental group was higher than the control group, no significant statistic at level of 0.05 by comparing with statistical method of t-test (n=29). It indicated that e-learning system can be used as a practical tool for increasing skill of the samples as well as correspondence between them in classroom.

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Stapór, Pawel. « A two-dimensional simulation of solidification processes in materials with thermo-dependent properties using XFEM ». International Journal of Numerical Methods for Heat & ; Fluid Flow 26, n^o 6 (1 août 2016) : 1661–83. http://dx.doi.org/10.1108/hff-01-2015-0018.

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Purpose – The purpose of this paper is to carry out a finite element simulation of a physically non-linear phase change problem in a two-dimensional space without adaptive remeshing or moving-mesh algorithms. The extended finite element method (XFEM) and the level set method (LSM) were used to capture the transient solution and motion of phase boundaries. It was crucial to consider the effects of unequal densities of the solid and liquid phases and the flow in the liquid region. Design/methodology/approach – The XFEM and the LSM are applied to solve non-linear transient problems with a phase change in a two-dimensional space. The model assumes thermo-dependent properties of the material and unequal densities of the phases; it also allows for convection in the liquid phase. A non-linear system of equations is derived and a numerical solution is proposed. The Newton-Raphson method is used to solve the problem and the LSM is applied to track the interface. Findings – The robustness and utility of the method are demonstrated on several two-dimensional benchmark problems. Originality/value – The novel procedure based on the XFEM and the LSM was developed to solve physically non-linear phase change problems with unequal densities of phases in a two-dimensional space.

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Andrade, Ana C. Balarin de, Paulo R. Aguiar, Martin A. Aulestia Viera, Felipe A. Alexandre, Pedro Oliveira Junior et Fabio R. L. Dotto. « Monitoring of the Ceramic Kerf During the Laser Cutting Process through Piezoelectric Transducer ». Proceedings 42, n^o 1 (14 novembre 2019) : 44. http://dx.doi.org/10.3390/ecsa-6-06529.

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Advanced ceramics are widely used in industry due to their unique properties. However, the machining of ceramic components by conventional methods is difficult due to their high level of hardness and brittleness. In this sense, laser beam machining (LBM) is presented as an alternative to conventional methods, enabling the machining of workpieces through more accurate and less invasive techniques. Despite the advantages of laser machining, the process still needs to be studied in detail, as advanced ceramic machining is considered a stochastic process. Thus, real-time monitoring systems are required in order to optimize the ceramic laser machining. Therefore, this paper proposes a novel method for monitoring the cutting kerf in the laser cutting process of ceramic components using a low-cost piezoelectric transducer (PZT) and digital signal processing. Tests were performed on the surface of an alumina ceramic workpiece under different machining conditions. The cutting kerf was measured by a digital microscope and the raw signals from the PZT transducer were collected at a sampling rate of 2 MHz. Time domain and frequency domain analyses were performed in order to find a frequency band that best correlates with the process conditions. Finally, a linear regression was calculated in order to correlate the PZT signal and the measured kerf. The results showed that the piezoelectric transducer was sensitive to the acoustic activity generated during the process, allowing the real-time monitoring of the cutting kerf. Thus, the approach proposed in this paper can be used efficiently in the monitoring of the laser cutting process.

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Fakour, Mehdi, Alireza Rahbari, Hesam Moghadasi, Iman Rahimipetroudi, Davood Domairry-Ganji et Mostafa Varmazyar. « Analytical study of unsteady sedimentation analysis of spherical particle in Newtonian fluid media ». Thermal Science 22, n^o 2 (2018) : 847–55. http://dx.doi.org/10.2298/tsci160602181f.

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Unsteady settling behavior of solid spherical particles falling in water as a Newtonian fluid is investigated in this research. Least square method (LSM), Galerkin method, LSM-Pad?, and numerical model are applied to analyze the characteristics of the particles motion. The influence of physical parameters on terminal velocity is discussed and it is showed that LSM and Galerkin method are efficient techniques for solving the governing equation. Among these methods, LSM-Pad? demonstrates the best agreement with numerical results. The novelty of this work is to introduce new analytical methods for solving the non-linear equation of sedimentation applicable in many industrial and chemical applications.

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Tyapin, Alexander G. « Combination of modal responses in linear spectral method : comparison of different formulae for correlation coefficients ». Earthquake Engineering. Construction Safety, n^o 1 (25 février 2021) : 32–42. http://dx.doi.org/10.37153/2618-9283-2021-1-32-42.

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Linear-spectral method (LSM) is still the common method for the seismic design analysis. "One-component one-mode" responses, obtained by static analysis in the conventional variant of LSM, are combined twice: first for different modes but for each single excitation component separately, then for the different excitation components. In the alternative LSM variant presented in the Russian code SP 14.13330, first one chooses the "most dangerous" direction of the one-component excitation for each mode; then calculates the "one-mode" response for this excitation, and finally these responses are combined. In both cases the combination is performed using the complete quadratic combination (CQC) rule. Different documents suggest different formulae for the correlation coefficients. In the paper different formulae are compared to each other. The goal is to limit the number of calculated coefficients and decrease the amount of calculations.

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Aramini, R., M. Brignone et M. Piana. « The linear sampling method without sampling ». Inverse Problems 22, n^o 6 (27 octobre 2006) : 2237–54. http://dx.doi.org/10.1088/0266-5611/22/6/020.

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