Significant Increase In Power Research Articles

Noise equalization scheme based on probabilistic shaping and complex-valued ANN for dual-polarization continuous spectrum NFDM system with high-order modulation formats

In dual-polarization continuous spectrum nonlinear frequency division multiplexing (DP-CS NFDM) systems, the presence of noise destroys the independence between subcarriers in the nonlinear spectral domain (NSD). Additionally, as the modulation order and the number of subcarriers increase, the signal power increases and the effect of noise on the performance of the system becomes more severe. In this paper, we propose a noise equalization scheme based on probabilistic shaping (PS) and complex-valued neural network (c-ANN) for dual-polarization transmission CS NFDM system with high-power signals. The scheme utilizes PS to reduce the distribution probability of high-power constellation points of the signal with high-order modulation format, to decrease the peak-to-average power ratio of the continuous spectrum subcarriers and the average power of the signal, which can achieve the suppression and equalization of the amplifier spontaneous emission (ASE) noise and the processing noise. In addition, the scheme uses the c-ANN to effectively reduce the correlation between subcarriers caused by the noise and improve the system performance. The effectiveness of the proposed scheme is verified in the DP-CS NFDM system, and the simulation results show that the Q-factor gain is enhanced by roughly 1.1 dB and 0.8 dB for the number of subcarriers of 128 and 256, respectively, compared to the classic nonlinear Fourier transform (NFT) scheme. Among them, with different noise figure (NF) and satisfying the 7% forward error correction (FEC) threshold, the 512QAM signal with an entropy of 8 after equalization increase the transmission distance by 80 km longer than that of uniform 256QAM signals for the number of subcarriers of 128. Compared with the joint scheme based on PS and real-valued neural network (r-ANN), this scheme has better equalization performance at the same complexity, and the complexity can be reduced by 50% under the same performance.

The Effect of Alpha Binaural Beats Auditory Stimulation on Quantitative Electroencephalography (QEEG) and Pain Intensity among Tension-Type Headache Patients

Tension-type headaches, the most prevalent primary headaches affecting 2-5% of the population, significantly impact sufferers' well-being. These headaches present a persistent health challenge, constituting a considerable portion of neurologist outpatient visits. Effectively managing tension-type headaches remains challenging and can lead to notable morbidity if untreated. Treatment typically involves prophylactic pharmacological therapy alongside non-pharmacological interventions. Among non-medication therapies, brainwave entrainment using binaural beats emerges as a promising option for chronic headaches. This experimental research employed a pre-test and post-test design over a 5-day period (30 minutes daily) to assess Alpha Binaural Beats Auditory stimulation's impact on the QEEG pattern and pain intensity reduction in tension-type headache patients. The study, involving 32 participants, revealed a statistically significant increase in relative alpha wave power (p-value of 0.000) and a significant decrease in relative beta wave power (p-value of 0.045) after exposure to alpha binaural beats. Additionally, the Numerical Rating Scale (NRS) recorded a statistically significant decrease in pain intensity (p-value of 0.000). These findings suggest that Alpha binaural beats contribute to increased alpha wave activity, decreased beta wave activity in the QEEG pattern, and a substantial reduction in pain intensity associated with tension-type headaches. However, further research is needed to explore cumulative effects and long-term sustainability in tension-type headache patients, advancing our understanding and application of this therapy.

Isoflurane anesthesia suppresses gastric myoelectric power in the ferret.

Gastric myoelectric signals have been the focus of extensive research; although it is unclear how general anesthesia affects these signals, and studies have often been conducted under general anesthesia. Here, we explore this issue directly by recording gastric myoelectric signals during awake and anesthetized states in the ferret and explore the contribution of behavioral movement to observed changes in signal power. Ferrets were surgically implanted with electrodes to record gastric myoelectric activity from the serosal surface of the stomach, and, following recovery, were tested in awake and isoflurane-anesthetized conditions. Video recordings were also analyzed during awake experiments to compare myoelectric activity during behavioral movement and rest. A significant decrease in gastric myoelectric signal power was detected under isoflurane anesthesia compared to the awake condition. Moreover, a detailed analysis of the awake recordings indicates that behavioral movement is associated with increased signal power compared to rest. These results suggest that both general anesthesia and behavioral movement can affect the signal power of gastric myoelectric recordings. In summary, caution should be taken in studying myoelectric data collected under anesthesia. Further, behavioral movement could have an important modulatory role on these signals, affecting their interpretation in clinical settings.

Nanostructured Oxide (SnO2, FTO) Thin Films for Energy Harvesting: A Significant Increase in Thermoelectric Power at Low Temperature.

Previous studies have shown that undoped and doped SnO2 thin films have better optical and electrical properties. This study aims to investigate the thermoelectric properties of two distinct semiconducting oxide thin films, namely SnO2 and F-doped SnO2 (FTO), by the nebulizer spray pyrolysis technique. An X-ray diffraction study reveals that the synthesized films exhibit a tetragonal structure with the (200) preferred orientation. The film structural quality increases from SnO2 to FTO due to the substitution of F- ions into the host lattice. The film thickness increases from 530 nm for SnO2 to 650 nm for FTO films. Room-temperature electrical resistivity decreases from (8.96 ± 0.02) × 10-2 Ω·cm to (4.64 ± 0.01) × 10-3 Ω·cm for the SnO2 and FTO thin films, respectively. This is due to the increase in the carrier density of the films, (2.92 ± 0.02) × 1019 cm-3 (SnO2) and (1.63 ± 0.03) × 1020 cm-3 (FTO), caused by anionic substitution. It is confirmed that varying the temperature (K) enhances the electron transport properties. The obtained Seebeck coefficient (S) increases as the temperature is increased, up to 360 K. The synthesized films exhibit the S value of -234 ± 3 μV/K (SnO2) and -204 ± 3 μV/K (FTO) at 360 K. The estimated power factor (PF) drastically increases from ~70 (μW/m·K2) to ~900 (μW/m·K2) for the SnO2 and FTO film, respectively.

Alpha modulation via transcranial alternating current stimulation in adults with attention-deficit hyperactivity disorder.

One potential therapy treating attention-deficit/hyperactivity disorder (ADHD) is to modulate dysfunctional brain activations using brain stimulation techniques. While the number of studies investigating the effect of transcranial direct current stimulation on ADHD symptoms continues to increase, transcranial alternating current stimulation (tACS) is poorly examined. Previous studies reported impaired alpha brain oscillation (8-12 Hz) that may be associated with increased attention deficits in ADHD. Our aim was to enhance alpha power in adult ADHD patients via tACS, using different methods to explore potential therapeutic effects. Undergoing a crossover design, adults with ADHD received active and sham stimulation on distinct days. Before and after each intervention, mean alpha power, attention performance, subjective symptom ratings, as well as head and gaze movement were examined. Frequency analyses revealed a significant power increase in the alpha band after both interventions. Despite a trend toward an interaction effect, this alpha power increase was, however, not significantly higher after active stimulation compared to sham stimulation. For the other measures, some additional pre-post effects were found, which were not intervention-related. Our study cannot provide clear evidence for a tACS-induced increase in alpha power in adult ADHD patients, and thus no stimulation related improvement of attention parameters. We provide further recommendations for the future investigation of tACS as a potential ADHD treatment.

An application of artificial neural network (ANN) for comparative performance assessment of solar chimney (SC) plant for green energy production

This study aims to optimize the power generation of a conventional Manzanares solar chimney (SC) plant through strategic modifications to the collector inlet height, chimney diameter, and chimney divergence. Employing a finite volume-based solver for numerical analysis, we systematically scrutinize influential geometric parameters, including collector height (hi = 1.85 to 0.1 m), chimney inlet diameter (dch = 10.16 to 55.88 m), and chimney outlet diameter (do = 10.16 to 30.48 m). Our findings demonstrate that reducing the collector inlet height consistently leads to increased power output. The optimal collector inlet height of hi = 0.2 m results in a significant power increase from 51 to 117.42 kW (~ 2.3 times) without additional installation costs, accompanied by an efficiency of 0.25%. Conversely, enlarging the chimney diameter decreases the chimney base velocity and suction pressure. However, as turbine-driven power generation rises, the flow becomes stagnant beyond a chimney diameter of 45.72 m. At this point, power generation reaches 209 kW, nearly four times greater than the Manzanares plant, with an efficiency of 0.44%. Nevertheless, the cost of expanding the chimney diameter is substantial. Furthermore, the impact of chimney divergence is evident, with power generation, collector efficiency, overall efficiency, and collector inlet velocity all peaking at an outer chimney diameter of 15.24 m (corresponding to an area ratio of 2.25). At this configuration, power generation increases to 75.91 kW, approximately 1.5 times more than the initial design. Remarkably, at a low collector inlet height of 0.2 m, combining it with a chimney diameter of 4.5 times the chimney inlet diameter (4.5dch) results in an impressive power output of 635.02 kW, signifying a substantial 12.45-fold increase. To model the performance under these diverse conditions, an artificial neural network (ANN) is effectively utilized.

Control laws of a salient pole synchronous machine in a mine electric locomotive

Relevance. The need to find effective control of a traction synchronous motor with permanent magnets in a mining electric locomotive under conditions of limitation of current and voltage supplied to its windings from an autonomous power source. Aim. To choose a control law that ensures an increase in a mine electric locomotive mileage on one battery charge with its speed growth. Object. Control laws of a salient pole synchronous motor with permanent magnets of a mining electric locomotive; laws of current control along the transverse axis; control by the current minimum and control by minimizing the reactive power of a salient pole synchronous machine. Methods. Analysis of the state of the electric machine with different formation of control of an electric drive in the mine electric locomotive. The main limiting indicators of an electric machine with voltage and current limitation were considered. For each control law, the results of mathematical modeling are shown in graphical and tabular form. Results. The analysis of the current control law along the transverse axis demonstrates a significant increase in reactive power with increasing load. In an hourly mode of operation, the reactive power exceeds the active power spent on the movement of the electric locomotive. When limiting the current and voltage, the minimum current control allows you to increase the electromagnetic torque by 12.7% in hourly operation. The maximum engine speed is increased by 13%. The maximum power spent on the electric locomotive movement increases by 33%. Reactive power is reduced by 29%. With reactive power minimization, despite the decrease in the electromagnetic torque in the hourly mode of operation by 4.8%, the maximum possible engine speed increases by 53%, the power spent on the electric locomotive movement increases by 50%.

Differences in Lift Quality During the Barbell Back Squat When Using Perceived Recovery Status-Regulated Intrasession Recovery Compared With Standardized Recovery Intervals.

Wolfe, AA, Laurent, CM, Tolusso, DV, and Rinehart, AN. Differences in lift quality during the barbell back squat when using perceived recovery status-regulated intrasession recovery compared with standardized recovery intervals. J Strength Cond Res 38(3): 444-449, 2024-The current investigation examined kinetic differences between standardized and perceptually regulated rest internals during power-based resistance training. Recreationally resistance-trained men ( n = 7) and women ( n = 7) completed 3 training sessions. Session 1 consisted of barbell back squat (SQ) 1 repetition maximum (1RM) testing. Two counterbalanced subsequent sessions of perceptually regulated vs. standardized intrasession recovery for 5 sets of 6 repetitions of SQ at 80% 1RM were completed. Lift quality was assessed using a barbell accelerometer that measured concentric and eccentric power and force outputs for each repetition. In each set, subjects reported a rating of perceived exertion (RPE) followed by passive rest for either 2 minutes or a self-selected period using the Perceived Recovery Status (PRS) scale. For the self-selected session, when an individual reported a PRS at level "7," they were instructed to begin the next set. Data were analyzed using a 2 (session) × 5 (set) repeated-measures ANOVA with Bonferroni post hoc analyses performed when appropriate. No significant main effects or interactions were observed for any set quality metrics in the concentric phase or eccentric phase, except peak eccentric power ( p = 0.01). Post hoc analyses revealed a significant increase in peak eccentric power from set 1 to set 2 ( p = 0.003) only. Finally, no significant difference between self-selected vs. standardized work-to-rest strategies on RPE ( p = 0.547) was expressed. These data suggest perceptually regulated intrasession recovery selection yields equivalent lift quality as standardized rest recommendations. Therefore, PRS utilization may provide a more simplified and individualized method of between-set rest prescriptions.

Selective striatal fast-spiking interneuron inhibition induces cortical seizure.

Whether striatal fast-spiking interneurons are involved in cortical synchronization remains elusive. We performed acute microinjections of a selective FSI-AMPA receptor antagonist into the sensorimotor striatum of non-human primates to verify whether selective FSI inhibition within the sensorimotor striatum could potentially modify cortical excitability, thereby triggering focal seizures. Experiments were performed on three fascicularis monkeys. During each experimental session, low volumes of IEM-1460 (4-8 μL) were injected slowly at 1 μL/min. Spontaneous behavioral changes were classified according to the Racine scale modified for primates. These induced motor behaviors were correlated with electroencephalographic (EEG and EMG) measures. Power spectrum and time-frequency analysis were performed and compared between each period of interest. Pharmacological selective inhibition of striatal fast-spiking INs induced focal motor seizures. Back averaging confirmed that myoclonic activity was closely linked to cortical spikes-and-waves epileptic activity, with a significant increase in cortical EEG power in all studied frequency bands (p < .0001). Thus, striatal FSIs likely play a role in controlling cortical excitability through the cortico-striato-thalamo-cortical pathway. They may contribute to the pathophysiology of focal motor epilepsies by modulating the threshold at which focal motor seizures are triggered.

The effects of 12 weeks resistance training and vitamin D administration on neuromuscular joint, muscle strength and power in postmenopausal women

BackgroundThis study aimed to examine the effects of 12 weeks of resistance training (RT) and vitamin D (VitD) supplementation on muscle strength and C-terminal agrin fragment (CAF) and Neurotrophin-3 (NT-3) concentrations as potential biomarkers in postmenopausal women. MethodsThis was a randomized double-blind placebo-controlled study. Forty-four healthy postmenopausal women (55.84 ± 4.70 years and 29.61 ± 4.26 kg/m2) were randomly assigned into four groups: (1) Resistance training + placebo (RT + PLA), (2) Vitamin D supplementation (VitD), (3) Resistance training + vitamin D (RT + VitD), and (4) Placebo (PLA). VitD was supplemented as an oral capsule containing 50000 IU of cholecalciferol every two weeks. RT involved leg press, chest press, leg extension, leg curl, and shoulder press exercises, performed with 3–4 sets at 70–85 % of 1RM, three times a week. ResultsCirculating levels of CAF and NT-3 did not significantly change following the intervention period in the study groups (p > 0.05). There were significant increases in upper and lower body muscle strength and power for RT + VitD and RT + PLA ( < 0.05), but not for VitD or PLA (p > 0.05). The muscle function gains for RT + VitD and RT + PLA were higher than those for VitD and PLA but did not differ between them. Conclusion12-week of RT interventions resulted in significant increases in muscle strength and power in postmenopausal women. However, VitD supplementation did not result in any additional benefits. The positive changes in muscle function promoted by RT do not seem to be associated with changes in the neuromuscular joint via the CAF or NT-3 as potential biomarkers.

A study on neural changes induced by sauna bathing: Neural basis of the "totonou" state.

Saunas are becoming increasingly popular worldwide, being an activity that promotes relaxation and health. Intense feelings of happiness have been reported shortly after enjoying a hot sauna and cold water, what is known in Japan as the "totonou" state. However, no research has investigated what occurs in the brain during the "totonou" state. In the present study, participants underwent a sauna phase, consisting of three sets of alternating hot sauna, cold water, and rest. We elucidated changes in brain activity and mood in the "totonou" state by measuring and comparing brain activity and emotional scales before and after the sauna phase and during the rest phase in each set. We found significant increases in theta and alpha power during rest and after the sauna phase compared to before the sauna phase. Moreover, in an auditory oddball task, the p300 amplitude decreased significantly and MMN amplitude increased significantly after the sauna phase. The increase in MMN indicates higher activation of the pre-attentional auditory process, leading to a decrease in attention-related brain activity P300. Hence, the brain reaches in a more efficient state. Further, the response time in behavioral tasks decreased significantly. In addition, the participants' subjective responses to the questionnaire showed significant changes in physical relaxation and other indicators after being in the sauna. Finally, we developed an artificial intelligence classifier, obtaining an average accuracy of brain state classification of 88.34%. The results have potential for future application.

Evaluating the impact of water reuse educational videos on water reuse perceptions using EEG/event related potential

As climate change and population growth increasingly stress freshwater resources, government agencies and scientists have recognized the importance of water reuse (the beneficial use of reclaimed or recycled water). While end users (municipalities and farmers) are largely open to exploring water reuse, a barrier to using this water source is the public's negative perception, or the ‘yuck factor’. Recognizing that water reuse is becoming a necessity, there is an urgent need to determine how to improve public acceptance of this water source. Increasing knowledge has been identified as a critical method for improving the adoption of sustainable practices, but to date, there has been a lack of outcome studies on the ability of water reuse education materials to change perceptions. Previous studies have relied heavily on self-reported concerns and perceptions which are limited by bias and social expectations, and their results have failed to substantially change water reuse education efforts, and by extension failed to substantially improve water reuse perceptions. We propose the integration of psychology for evaluating the effectiveness of water reuse education and outreach efforts. The purpose of this study was to determine if water reuse educational videos modulate perceptions of water reuse terms. Participants were recruited from a university campus and completed pre-intervention surveys on water reuse knowledge, willingness to use recycled water, and preferred water reuse information sources. We then measured changes in neural activity in response to multiple categories of water reuse terms pre- and post-exposure to water reuse education videos using electroencephalogram (EEG). Through EEG we measured event related potential (ERP), which assesses sustained engagement with the cues (late positive potential (LPP) amplitude), and alpha power. Participants also completed a pre/post exposure battery involving five tasks, in randomized order, presented before and after viewing videos. Sixty-eight percent of survey participants had previously heard of water reuse and 91% reported willingness to use recycled water for at least one activity. Participants reported obtaining water reuse information mostly from the internet (77%) and preferred to receive additional information mainly by watching online videos (73%). We observed significant increases in alpha power, corresponding to feelings of relaxation, in response to seven of eight water reuse term categories post-video exposure. These findings show that water reuse educational videos can change perceptions of water reuse. Our results point to the possibility of validating and increasing the effectiveness of water reuse education materials using sophisticated neurocognitive measures.

The Impact of Indoor Plants on Patient Recovery: Physiological and Psychological Effects in Dental Clinics

Patient recovery and well-being in healthcare settings can be influenced by various factors, including the stress induced by hospitalization and medical care. This study investigated the impact of indoor plants on patient recovery in dental clinics using state-of-the-art techniques to address the limited evidence supporting the claim that nature can alleviate stress and pain in hospitals. Thirty patients were randomly assigned to either a room with indoor plants or a control room without plants for a duration of 5 minutes after their treatment. Physiological responses were assessed using electroencephalography (EEG), heart rate variability, and skin conductance, whereas psychological responses were evaluated using the State-Trait Anxiety Inventory (STAI) and a visual analogue scale (VAS). The results revealed a significant increase in alpha wave power in the frontal region, indicating enhanced relaxation, as well as a significant increase in parasympathetic activity, suggesting improved autonomic balance. Furthermore, a significant decrease in skin conductance was observed when indoor plants were present compared with their absence, indicating reduced physiological arousal. Psychological assessments using the STAI demonstrated lower levels of stress and anxiety, whereas the VAS indicated reduced pain intensity among participants. Overall, these findings suggest that the presence of indoor plants contributes to patients’ relaxation and improved coping mechanisms during the recovery process. This study highlights the significance of incorporating indoor plants into healthcare settings to enhance patients’ overall well-being and promote positive recovery outcomes.

Quantitative EEG analysis in typical absence seizures: unveiling spectral dynamics and entropy patterns.

A typical absence seizure is a generalized epileptic event characterized by a sudden, brief alteration of consciousness that serves as a hallmark for various generalized epilepsy syndromes. Distinguishing between similar interictal and ictal electroencephalographic (EEG) epileptiform patterns poses a challenge. However, quantitative EEG, particularly spectral analysis focused on EEG rhythms, shows potential for differentiation. This study was designed to investigate discernible differences in EEG spectral dynamics and entropy patterns during the pre-ictal and post-ictal periods compared to the interictal state. We analyzed 20 EEG ictal patterns from 11 patients with confirmed typical absence seizures, and assessed recordings made during the pre-ictal, post-ictal, and interictal intervals. Power spectral density (PSD) was used for the quantitative analysis that focused on the delta, theta, alpha, and beta bands. In addition, we measured EEG signal regularity using approximate (ApEn) and multi-scale sample entropy (MSE). Findings demonstrate a significant increase in delta and theta power in the pre-ictal and post-ictal intervals compared to the interictal interval, especially in the posterior brain region. We also observed a notable decrease in entropy in the pre-ictal and post-ictal intervals, with a more pronounced effect in anterior brain regions. These results provide valuable information that can potentially aid in differentiating epileptiform patterns in typical absence seizures. The implications of our findings are promising for precision medicine approaches to epilepsy diagnoses and patient management. In conclusion, our quantitative analysis of EEG data suggests that PSD and entropy measures hold promise as potential biomarkers for distinguishing ictal from interictal epileptiform patterns in patients with confirmed or suspected typical absence seizures.

Growth of Positioning Errors with Increasing Signal Power of Global Navigation Satellite Systems

Growth of Positioning Errors with Increasing Signal Power of Global Navigation Satellite Systems

The CV is dead, long live the CV!

Abstract Biology has an increasing need to reconsider the tools used to assess the variability of measurements, in addition to their central tendency. More than 100 years after Pearson's publication, most biologists still use the “good old” Pearson's coefficient of variation, PCV, despite its documented flaws such as sensitivity to excess zero values and/or irrelevant low mean values, which may compromise its use in some biological applications. A new statistic was developed in 2017 by Kvålseth, KCV, which is easy to implement. Unlike PCV, KCV is bounded (between 0 and 1), and it can be computed from PCV, ensuring backward compatibility with past studies. In addition to simulated data, we used the recent MASTREE+ database comprising the time series of the fruiting dynamics of perennial plants worldwide to compare the properties of PCV and KCV. Using as a benchmark the loose hump‐shaped relationship between the interannual variability of fruiting and latitude, KCV led to significant increase in statistical power as it required almost half as many time series as PCV to detect the relationship. Perhaps most importantly, simulated data showed that KCV allows huge reductions in the length of time series required to estimate the population true variability, saving more than half the duration of long‐term monitoring if fruiting fluctuations are very large, which is common in perennial plant species. Compared to the widely used PCV, KCV has great accuracy for estimating and analysing variability in biology, while strongly increasing statistical power. Selecting appropriate tools to assess the variability of measurements is crucial, particularly where the variability is of primary biological interest. Using Kvålseth's KCV is a promising avenue to circumvent the well‐known issues of the former Pearson’ PCV, its properties remain to be explored in other fields of biology, for purposes other than purely statistical ones (e.g. estimating heritability or evolvability of traits).

Attention-related power and functional connectivity modulation associated with long-term alpha neurofeedback training

Electroencephalography (EEG) based Neurofeedback training (NFT) is a non-invasive, brain-modulation technique that can improve the subject’s attention. In this research, the effectiveness of long-term NFT on the subject’s attention is explored. Real-time frontal lobe alpha band (8–13 Hz) power was used as feedback. The subjects were divided into the NFT group (n = 25) which received training and the control group (n = 25) which did not. All the subjects participated in the attention network task (ANT) at three stages i.e., before, mid, and at the end of NFT sessions. The EEG and behavioral data (Response time (RT) of the ANT task) were recorded for all subjects. The EEG data were pre-processed using a manual artifact removal procedure to avoid event-related information loss. Alpha band modulation can affect other bands such as theta (4–8 Hz) and beta (13–30 Hz) hence event-related functional connectivity (FC) and band power (BP) were analyzed in these bands as well. In event-related analysis, a significant increase (ANOVA & T-Test: P < 0.05) in theta and alpha power and FC within the NFT group was observed after NFT sessions whereas the changes observed within the control group were not significant. The RT of the subjects in the NFT group decreased. The increase in event-related power and connectivity within the theta and alpha band and the decrease in RT in the NFT group indicate the effectiveness of NFT sessions in the enhancement of attention.

Floating Photovoltaic Performance Evaluation Using Novel Cooling System Case Study

Photovoltaic panels nowadays are considered one of the most important methods for generating electricity directly from the sun as a green energy resource. The photovoltaic cells convert about 20% of solar energy to electric power, and the rest is converted to heat that increases the cells temperature. The photovoltaic performance decreases by about 0.4%–0.5% for each 1°C increase in cell temperature. This article studies the effect of using a novel cooling design to cool floating photovoltaic panels with natural cold water from natural sources. ANSYS has been used to conduct a series of simulations under different boundary conditions like solar radiation, ambient temperature, and cooling water temperature at Duhok Dam Reservoir, KRI. The results of the proposed cooling module showed a significant increase in efficiency (1.26%–2.49%) and power performance (17.76–36.81W) and a significant increase in power (6.43%–14.89%) compared to the non-cooled module. Thus, using an active cooling method for floating panels could be a typical option to boost the output of the solar panels. The results of this research have outperformed other research, with a power increase rate of about 14.1%.

Impact of short term training on morphological, physical fitness and physiological variables of middle distance runners

Purpose: The present study was designed to investigate the effects of short term training on morphological, physical fitness and physiological determinants of middle distance runners. Method: Total of 97 male volunteers (age: 18-20 yrs.) (40- sedentary control, and 57- middle distance runners) were included randomly, and 17 middle distance runners were excluded. The rest were divided into (a) Sedentary Control Group (SCG, n = 40) and (b) Middle Distance Runners Group (MDR, n = 40). The volunteers of MDR followed a training schedule of 2 hrs/d, 5days/wk., for 6 wks.; no training was given in SCG. Results: A significant (p &lt; .05) increase in strength (of grip, back, leg, upper body strength, abdominal), anaerobic power, flexibility, VO2max, FEV1, FVC, PEFR; and decrease (p &lt; .05) in body mass, body fat and sprint time, heart rate (during rest, sub-maximal exercise and recovery) among the volunteers of MDR after 6 weeks of training. This study showed positive correlation between standing broad jump and height (r = +0.51, p &lt; .05); and between speed and leg strength (r = +0.52, p &lt; .05). Conclusion: Training have a positive impact on morphological, physical fitness and physiological variables of middle distance runners. Further research would provide conclusive results that can be extrapolated to general population.

Control of multiple PTOs in single OWC air chambers

The paper presents the study of multi-PTO interaction in single-air chamber oscillating-water-column (OWC) wave energy converters (WECs). This strategy seeks: i) tunning system's performance to sea states, ii) increasing reliability through modular designs that are easier to install and replace, and iii) increasing conversion efficiency through better matching between available power and electric conversion equipment. The strategy was assessed through a novel non-linear time-domain model for OWC WECs implemented in the multi-physics object-oriented language Modelica. The model considers multiple degrees of freedom associated with the various PTOs. Different case studies are presented to show the proposed approach's versatility, some of the constraints expected in real implementations, and potential pathways to overcome them. The wave-to-wire model considers air compressibility and non-linear power take-off systems, which is fundamental to assessing the damping level variation required for each sea state considered. The cases presented are for a fixed-structure coaxial-duct OWC WEC, but the results are generalisable for floating structures. Results show a significant increase in mean annual power, and control strategies are proposed for power maximisation. Furthermore, some critical points are shown in the operational conditions' envelop for the system under a selected Portuguese wave climate. The identification of these critical values is important for the control of the OWC WECs. This study represents an advance in the control strategies considering multiple PTOs for a single OWC air chamber to foster innovation actions.