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The performance, safety, and cycle life of lithium-ion batteries (LiBs) are all known to be greatly influenced by temperature. In this work, an innovative cooling system is employed with a Reynolds number range of 15,000 to 30,000 to minimize the temperature of LiB cells. The continuity, momentum, and energy equations are solved using the Finite Volume Method (FVM). The computational fluid dynamics software ANSYS Fluent is applied to calculate the flow and temperature fields and to analyze the thermal management system for 52 LiB cells. The arrangement of batteries leads to symmetrical flow and temperature distribution occurring in the upper and lower halves of the battery pack. The impacts of SiO2 distributed in a base fluid (water) are investigated. The results show that SiO2 nanofluid with the highest volume fractions of 5% has the lowest average temperature values at all investigated Reynolds numbers. The innovative cooling system highlights the enhancement of the cooling process by increasing the SiO2 concentrations, leading to the recommendation of the concentration of 5 vol% due to better thermal diffusion resulting from the enhanced effective thermal conductivity. The flow turbulence is increased by increasing the Reynolds number, which significantly enhances the heat transfer process. It is shown that increasing the Re from 15,000 to 22,500 and 30,000 causes increases in the Nu value of roughly 32% and 65%, respectively. [ABSTRACT FROM AUTHOR]

Curved veins and arteries make up the human cardiovascular system, and the peristalsis process underlies the blood flowing in these ducts. The blood flow in the presence of hybrid nanoparticles through a tapered complex wavy curved channel is numerically investigated. The behavior of the blood is characterized by the Casson fluid model while the physical properties of iron (Fe3O4) and copper (Cu) are used in the analysis. The fundamental laws of mass, momentum and energy give rise the system of nonlinear coupled partial differential equations which are normalized using the variables, and the resulting set of governing relations are simplified in view of a smaller Reynolds model approach. The numerical simulations are performed using the computational software Mathematica's built-in ND scheme. It is noted that the velocity of the blood is abated by the nanoparticles' concentration and assisted in the non-uniform channel core. Furthermore, the nanoparticles' volume fraction and the dimensionless curvature of the channel reduce the temperature profile. [ABSTRACT FROM AUTHOR]

Fault diagnosis is a major area of investigation for power system and intelligent system applications. This paper proposes an efficient and practical algorithm based on using wavelet MRA coefficients for fault detection and classification, as well as accurate fault location. A three-phase transmission line with series compensation is simulated using MATLAB software. The line currents at both ends are processed using an online wavelet transform algorithm to obtain wavelet MRA for fault recognition. Directions and magnitudes of spikes in the wavelet coefficients are used for fault detection and classification. After identifying the fault section, the summation of the sixth level MRA coefficients of the currents are fed to adaptive neuro-fuzzy inference system (ANFIS) to obtain accurate fault location. The proposed scheme is able to detect all types of internal faults at different locations either before or after the series capacitor, at different inception angles, and at different fault resistances. It can also detect the faulty phase(s) and can differentiate between internal and external faults. The simulation results show that the proposed method has the characteristic of a simple and clear recognition process. We conclude that the algorithm is ready for series compensated transmission lines. [ABSTRACT FROM AUTHOR]

The general aim of this paper is to develop an accurate fault-location scheme that can solve the problems affecting the accuracy of the existing conventional fault locators achieving easier maintenance and restoration time reduction as well as economical aims. This consequently helps to fit the new deregulation policies and competitive marketing. This investigation successfully applies zero-sequence current (3I0) from the two terminals for earth high impedance fault (HIF) location, or negative-sequence currents from the two terminals of one faulted phase for line-to-line fault location. The HIF location is determined within only a maximum time of one cycle. The proposed scheme is insensitive to variations of different parameters, such as fault type, HIF behavior, wide-range transmission-line parameters variation, and fault inception angle. Staged fault testing results demonstrate that the proposed algorithm has feasible performance. [ABSTRACT FROM AUTHOR]

Purpose: To assess sleep disturbance patterns in breast cancer patients receiving adjuvant radiotherapy and/or chemotherapy in comparison to normal subjects, and their impact on quality of life., Methods: Seventy-four histologically proven breast cancer patients of both genders, aged 30 to 65 years, were classified into 2 groups. First group: 26 patients with breast cancer before receiving any treatment. Second group: 48 breast cancer patients, subdivided into group A (24 patients with adjuvant chemotherapy), and group B (24 patients with adjuvant radiotherapy). A control group consisted of 24 healthy individuals matched in age and sex with patient groups. Clinical assessment of sleep was done using the Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS) and one night Polysomnography (NPSG)., Results: No statistically significant difference regarding age and sex was found compared to control group. The severity of insomnia (ISI) was 29.2%, 4.2%, 7.7% and 0% for patients who received chemotherapy and/or radiotherapy, and comparison of patients without treatment and the control group showed statistical significance. Excessive daytime sleepiness was 37.5%, 25%, 26.9% and 0% for patients who received chemotherapy and/or radiotherapy, before receiving treatment, and the control groups respectively, the difference been significant. Comparison of patients who received treatment with those who did not and the control groups showed significant shortening of total sleep time, decrease of sleep efficiency and lengthening of sleep latency. Significant lengthening in stage 2 of non-rapid eye movement (NREM), while insignificant lengthening in stages 1, 3 and 4 of NREM sleep was noted. Significant reduction of rapid eye movement (REM) and total sleep time percentage were observed. Sleep apnea was insignificantly more common in breast cancer patients compared to healthy controls., Conclusion: Sleep-related changes in breast cancer patients should be used in planning best supportive care.