Root Mean Square Error Deviation Research Articles

Parameters extraction of three diode photovoltaic models using boosted LSHADE algorithm and Newton Raphson method

The (photovoltaic) PV models’ performance is strongly dependent on their parameters, which are mainly standing on the utilized method and the formulated objective function. Therefore, extracting the PV models’ parameters under several environmental conditions is crucial for maximizing its reliability, accuracy and reducing the system’s overall cost. According to the scope of this problem, several methodologies have been extensively applied to tackle this problem. Thus, this paper presents an enhanced version of the well-known LSHADE (ELSHADE) method by integrating various contributions in the algorithm itself and the objective function to determine three diode PV models’ parameters. In ELSHADE, the population is divided into two phases: a robust mutation scheme performs the first phase, and the chaotic-guided strategy is utilized in the second stage. Moreover, an improved Newton Raphson (INR) method is presented to address the I–V curve equation’s chaotic behavior effectively. The results confirm that the proposed ELSHADE-INR can precisely find the global solutions by comparing it with state-of-the-art algorithms and its superiority demonstrated in several statistical criteria under real experimental data. The average values of root mean square error (RMSE), mean bias error, determination coefficient, deviation of RMSE, test statistical, absolute error, and CPU-execution time are 0.0060 and 5.88e-05, 0.9999, 2.54e-05, 0.0538, and 0.0042, 11.39s, respectively. We observed that the proposed ELSHADE is robust and stable, and very promising in its origin to obtain high-quality and accurate parameters. This paper is supported by https://aliasgharheidari.com/publications/ELSHADE.html.

Iterative volume of interest based 4D cone-beam CT.

4D cone-beam CT (CBCT) has potential applications in soft tissue alignment and tumor motion verification at the time of radiation treatment. However, prominent streak artifacts with conventional image reconstructions have limited its clinical use and alternative reconstructions are generally too computationally expensive for the time available. We propose an iterative volume of interest based (I4D VOI) reconstruction technique, where 4D reconstruction is only performed within a VOI, to limit streak artifacts with limited added computation time. The I4D VOI technique is compared to standard cone-beam filtered back projection (FDK), an FDK VOI technique, and unconstrained total variation (TV) minimization by comparing tumor motion quantification errors and image quality. 14 long CBCT scans (6.5 to 12 min) of patients receiving radiation treatment for lung cancer were used for the comparison. Rigid registration between phase images of FDK reconstructions using all projections were used to quantify the gold standard motion. Projections were removed to simulate 2 minute scans and these new projection sets were used for each of the test reconstructions. Excluding two patients where registration failed, the average root mean square (RMS) error for each method was as follows: 1.5 ± 0.2 mm for FDK, 1.4 ± 0.2 mm for FDK VOI, 1.3 ± 0.2 mm for I4D VOI, 1.7 ± 0.4 mm for low regularization TV minimization, and 1.1 ± 0.2 mm for high regularization TV minimization. No significant difference was observed between RMS error for I4D VOI and the other methods, except for unsmoothed FDK VOI (P = 0.02). An increase in RMS error difference between I4D VOI and smoothed FDK VOI was observed going from 2 min to 1 min scans (0.1 mm to 0.3 mm, P = 0.20 to P = 0.09). I4D VOI and FDK VOI reconstruction measured tumor trajectories with equivalent accuracy as TV minimization with improved bony anatomy image quality and computation time (I4D VOI was approximately 15 and 95 times faster than low and high regularization TV minimization, respectively). Within the VOI, streak artifact reduction compared to FDK VOI may be beneficial for tumor visualization and motion measurement, but requires further study.

Laboratory Calibration Procedures of the Hydra Probe Soil Moisture Sensor:Infiltration Wet-Up vs. Dry-Down

Impedance probes are popular electromagnetic soil moisture monitoring devices used for a variety of applications but require site-specific calibrations to provide accurate measurements. Several calibration techniques have been reported in the literature, although laboratory-based procedures involving wet-up (via upward or downward infiltration) and dry-down are commonly performed for permanently installed sensors. Wet-up calibrations can be completed substantially faster (<1 d) than dry-down calibrations (1–2 wk), but it is uncertain which technique is preferable to provide the most accurate calibration. The objective of this study was to compare the results obtained from laboratory-based infiltration wet-up and dry-down calibrations of the Stevens Hydra Probe soil moisture sensor. Soil samples for this study were obtained from agricultural sites in Saskatchewan, Canada, at depths of 5, 20, and 50 cm across a variety of textural compositions. Results demonstrate that utilizing either infiltration wet-up (according to the procedure in this study) or dry-down procedures provides accuracies of <0.061 m3 m−3 root mean square error (RMSE), which was superior to manufacturer calibration accuracy across all samples. However, superior calibration accuracies (i.e., the lowest RMSE) were achieved using the dry-down procedure across all soil samples, resulting in a lower RMSE of 0.01 to 0.04 m3 m−3 (at 95% confidence). A significant correlation (r value = 0.61, p < 0.05) exists between the differences in infiltration wet-up and dry-down calibration RMSEs and clay content. This suggests that the difference between the two procedures tested in this study is more significant in finer textured soils. The findings of this study indicate that the dry-down procedure produced the lowest RMSE and is therefore the preferred calibration procedure, particularly for finer textured soils.

Laboratory and Field Study of the Potential Benefits of Pinna Cue-Preserving Hearing Aids

The potential benefits of preserving high-frequency spectral cues created by the pinna in hearing-aid fittings were investigated in a combined laboratory and field test. In a single-blind crossover design, two settings of an experimental hearing aid were compared. One setting was characterized by a pinna cue-preserving microphone position, whereas the other was characterized by a microphone position not preserving pinna cues. Participants were allowed 1 month of acclimatization to each setting before measurements of localization and spatial release from speech-on-speech masking were completed in the laboratory. Real-world experience with the two settings was assessed by means of questionnaires. Seventeen participants with mild to moderate sensorineural hearing impairments completed the study. An inconsistent pinna cue benefit pattern was observed across the outcome measures. In the localization test, the pinna cue-preserving setting provided a significant mean reduction of 22° in the root mean square (RMS) error in the front-back dimension, with 13 of the 17 participants showing a reduction of at least 15°. No significant mean difference in RMS error between settings was observed in the left-right dimension. No significant differences between settings were observed in the spatial-unmasking test conditions. The questionnaire data indicated a small, but nonsignificant, benefit of the pinna cue-preserving setting in certain real-life situations, which corresponded with a general preference for that setting. No significant real-life localization benefit was observed. The results suggest that preserving pinna cues can offer benefit in some conditions for individual hearing-aid users with mild to moderate hearing loss and is unlikely to harm performances for the rest.

Effects of Environmental Noises on Fundamental Frequency Contours of Thai Expressive Speech

Problem statement: The expressive speech of Thai had been studied for a short period of time. An important feature of speech was fundamental frequency (F0) which defines the human speech prosody. It could be used to distinguish the difference between several types of expressive speech. The environmental noises affect the F0 contour for Thai dialects as concluded in the previous study. The study prosodic information of Thai speech with various speaking styles and several types of noises had not been conducted. Approach: Four different types of speaking styles were used; meanwhile four types of environmental noises were recorded with different levels of power. They were subsequently mixed together. The F0 contours from different types of speaking styles, different types of noises and different levels of noises were extracted. The Root Mean Square Error (RMSE) between the F0 contour of clean speech and the noise-corrupted speech was calculated. Results: In the experiments, four types of noises were included train, factory, car and air conditioner. Each type of speaking style included 10 samples of 10 utterances of male and female speech. Five levels of noises were varied from 0-20 dB compared with the clean speech. It could be notified that the effects of distinguishing types of noises were different. Four different types of speaking styles were also caused the differences in RMSEs. Conclusion: The recorded noises deteriorate the F0 contours for all types of speaking styles in Thai.

Effects of Environmental Noises on Fundamental Frequency Contours of Thai Dialects

Problem statement: Fundamental Frequency (F0) is an important speech feature defining the human speech prosody. It is the resultant of th e vibration of human's vocal chords in speech production. In Thai, there are four main dialects s poken by Thai people residing in four core region including central, north, northeast and south regio ns. Environmental noises are also playing an important role in corrupting the speech quality. Th e study of effects of noises the F0 contour for Tha i dialects reveals the important of noise reduction i ssue. Approach: Four types of environmental noises were recorded with different levels of power . It was subsequently mixed with clean speech. The F0 contours from different dialects, different types of noises and different levels of noises was extracted. The difference in term of Root Mean Square Error (RMSE) between the F0 contour of clean speech and the noise-corrupted speech was calculated. Results: In the experiments, each regional dialect includes 10 samples of 10 utteranc es with male and female speech. Four types of noises include train, factory, car and air conditio ner. Moreover, five levels of each type of noise are varied from 0-20 dB. The results show that effe cts of distinguish types of noises are different. Four kinds of regional dialects also cause the diff erences in RMSEs. Conclusion: The recorded noises deteriorate the F0 contours for all Thai dia lects.

On the global model for foF2 using neural networks

The use of neural networks (NNs) has been employed in this work to develop a global model of the ionospheric F2 region critical frequency, foF2. The main principle behind our approach has been to utilize parameters other than simple geographic coordinates, on which foF2 is known to depend, and to exploit the ability of NNs to establish and model this nonlinear relationship for predictive purposes. The foF2 data used in the training of the NNs were obtained from 59 ionospheric stations across the globe at various times from 1964 to 1986, on the basis of availability. To test the success of this approach, one NN (NN1) was trained without data from 13 stations, selected for their geographic remoteness, which could then be used to validate the predictions of the NN for those remote coordinates. These stations were subsequently included in our final NN (NN2). The input parameters consisted of day number (day of the year), universal time, solar activity, magnetic activity, geographic latitude, angle of meridian relative to subsolar point, magnetic dip angle, magnetic declination, and solar zenith angle. Comparisons between foF2 values determined using NNs and the International Reference Ionosphere (IRI) model (from Union Radio Scientifique Internationale (URSI) and International Radio Consultative Committee (CCIR) coefficients) with observed values are given with their root‐mean‐square (RMS) error differences for test stations. The results from NN2 are used to produce the global behavior of hourly values of foF2 and are compared with the IRI model using URSI and CCIR coefficients. The results obtained (i.e., RMS error differences), which compare favorably with the IRI models, justify this technique for global foF2 modeling.