Rotational Piezoelectric Energy Harvesting (RPZTEH) is widely used due to mechanical rotational input power availability in industrial and natural environments. This paper reviews the recent studies and research in RPZTEH based on its excitation elements and design and their influence on performance. It presents different groups for comparison according to their mechanical inputs and applications, such as fluid (air or water) movement, human motion, rotational vehicle tires, and other rotational operational principal including gears. The work emphasises the discussion of different types of excitations elements, such as mass weight, magnetic force, gravity force, centrifugal force, gears teeth, and impact force, to show their effect on enhancing output power. It revealed that a small compact design with the use of magnetic, gravity, and centrifugal forces as excitation elements and a fixed piezoelectric to avoid a slip ring had a good influence on output power optimisation. One of the interesting designs that future works should focus on is using gear for frequency up-conversion to enhance output power density and keep the design simple and compact.
ABSTRACT: Polypyrrole and polypyrrole / silver nanocomposites were fabricated by in-situ polymerization employing Ammonium Persulphate as an oxidizing agent. Nanocomposites were synthesized by combining polypyrrole and silver nanoparticles in various weight percentages (0.1%, 0.5%, 3%, 5% and 7% wt.). Crystallographic data were collected using X-ray diffraction. PPy particles were found to have an orthorhombic symmetry. In contrast, PPy/Ag nanocomposites were reported to have monoclinic structure. The crystallite size was determined by XRD using Scherrer equation and considered to be within 49 nm range. DC conductivity of pelletized samples was evaluated in the temperature range of 323.15k to 453.15k. The conductivity displayed an
... Show MoreOxidative stress plays a crucial role in the pathogenesis of peripheral artery disease (PAD). This study aimed to investigate the effect of clopidogrel on oxidative stress in PAD patients. Seventy subjects were divided into three groups: PAD patients before treatment (B-PAD), PAD patients after treatment with clopidogrel (A-PAD), and healthy controls. Serum levels of superoxide dismutase (SOD), copper (Cu), zinc (Zn), manganese (Mn), and oxidized protein were measured. SOD activities were also determined. The results showed that SOD activities, and SOD specific activities were significantly decreased in PAD patients compared to healthy individuals. After treatment with clopidogrel, SOD activities, and SOD specific activities were continuous
... Show MoreLuminescent sensor membranes and sensor microplates are presented for continuous or high-throughput wide-range measurement of pH based on a europium probe.
Allah legislated marriage and made it dwelling, fellowship and mercy between
the two couples, Prophet Moh'd (peace of Allah and blessing be upon him) ordered a
husband to look after his wife, treat her with full charity and make love with here
every kindly. On the other hand, he ordered a wife to obey her husband and respect
him deeply, nevertheless, some obstacles may sometimes be appeared within the life
of their marriage, this may be caused by either a husband or a wife. This problem is
called lifely disobedience (AL-Noshooz).
In the other words, this means that a wife begins to hate her husband, refuse his orders
and not obey him.
In brief, they hate each other which leads to some marks appear in their
m
Criticism, as an evaluative criterion, is a significant speech act for English language learners to improve their speech and actions in their academic life. Yet, it is realized differently across diverse cultures. Few studies have shown that the linguistics forms of one language are different from those available in another language. Hence, this study aims to investigate the cross-cultural similarities and differences between 60 Iraqi and Malay university learners in the use of criticism strategies. The data are collected using a Discourse Completion Test (DCT) and a Focus Group Interview (FGI). The data are coded based on Nguyen’s (2005) coding scheme of criticism in terms of the realization strategies. Qualitative
... Show MoreIn this paper a system is designed on an FPGA using a Nios II soft-core processor, to detect the colour of a specific surface and moving a robot arm accordingly. The surface being detected is bounded by a starting mark and an ending mark, to define the region of interest. The surface is also divided into sections as rows and columns and each section can have any colour. Such a system has so many uses like for example warehouses or even in stores where their storing areas can be divided to sections and each section is coloured and a robot arm collects objects from these sections according to the section’s colour also the robot arm can organize objects in sections according to the section’s colour.
This paper includes a comparison between denoising techniques by using statistical approach, principal component analysis with local pixel grouping (PCA-LPG), this procedure is iterated second time to further improve the denoising performance, and other enhancement filters were used. Like adaptive Wiener low pass-filter to a grayscale image that has been degraded by constant power additive noise, based on statistics estimated from a local neighborhood of each pixel. Performs Median filter of the input noisy image, each output pixel contains the Median value in the M-by-N neighborhood around the corresponding pixel in the input image, Gaussian low pass-filter and Order-statistic filter also be used. Experimental results shows LPG-PCA method
... Show MoreThe article considers a creolized text as a means of modern communication, describing its key verbal and visual components; the relationship of concepts polycode and creolized text has been shown; the universal basic image features have been called; the following kinds of creolized texts have been distinguished; it has been proved that the effective means of attracting the attention of the addressee is the use of expressive font features, which are divided into two groups: topographics (mechanisms of varying of areal syntagmatic of a text) and supragraphcs (change of typeface of font).
Cerium oxide CeO2, or ceria, has gained increasing interest owing to its excellent catalytic applications. Under the framework of density functional theory (DFT), this contribution demonstrates the effect that introducing the element nickel (Ni) into the ceria lattice has on its electronic, structural, and optical characteristics. Electronic density of states (DOSs) analysis shows that Ni integration leads to a shrinkage of Ce 4f states and improvement of Ni 3d states in the bottom of the conduction band. Furthermore, the calculated optical absorption spectra of an Ni-doped CeO2 system shifts towards longer visible light and infrared regions. Results indicate that Ni-doping a CeO2 system would result in a decrease of the band gap. Finally,
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