Traditional tree management is laborious and costly, thus this work aimed to study the performance of two different types of frond cutting saws (reciprocating saw and vibrating saw) and examine the two saws on five date palm varieties. Four parameters were examined, including cutting time for a single frond, the power needed for cutting a single frond, frond cutting productivity expressed as tree/h, and vibration conveyed to the worker’s hand. A field experiment was designed according to the nested randomized complete block design, including five date palm varieties as the main plot and the type of saw as a sub-plot. Means were compared using the least significant differences (LSD 0.05). Results indicated that Bream variety required the least time for frond cutting. The reciprocating saw exhibited efficiency in saving the time required for frond cutting, while the vibrating saw took significantly longer time needed for cutting a single frond. The highest number of fronds cut in one hour was recorded in Bream variety, again significantly higher than the number of other studied varieties. Moreover, the reciprocating saw achieved significantly higher productivity than the vibrating one, indicating that the productivity of the reciprocating saw is almost three times more than the vibrating saw. Maximum productivity was recorded in Bream variety, while the least was recorded in Tebarzal using the vibrating saw. Moreover, results indicate that the variety and the type of saw have a vital role in productivity since as the thickness of a frond increases, the cutting takes more time and ultimately reduces the number of date palms to be pruned per hour. Results also exhibited that vibrating saw reduced the consumed energy during frond cutting. Additionally, results revealed that the minimum power consumed by a vibrating saw was in Bream variety, while Tebarzal consumed the upmost energy when a reciprocating saw was used. Maximum vibration on X-axis was reported in Bream variety when a vibrating saw was used. Additionally, the reciprocating saw exhibited the highest vibration compared with the vibrating saw. Moreover, the reciprocating saw caused the lowest vibration in Tebarzal variety. Results indicated that the vibration imposed by both saws reached the maximum value in Bream variety. The vibrating saw resulted in the higher vibration toward Z axis, while the Reciprocating saw resulted in higher vibration toward X axis, which was more than eight times that recorded by the vibrating saw. Results indicate that vibration toward the Y axis increased significantly in Bream variety compared with others. Again, as in the situation with X and Z axis, the reciprocating saw exhibited the highest vibration compared to that resulted from using a vibrating saw which was more than three times the vibration caused by the vibrating saw.
The purpose of this research was to examine the impact of varying doses of ginger powder on broiler productivity. There were 180 commercial strain Ross 308 day old chicks utilized in the experiment, and each chick was weighed and allocated randomly among four treatments. Three different treatments were tested, each with a replication of 15 chicks. The diet was supplemented with 0.5, 1.0 and 2.0g/kg of ginger powder, respectively, as a control. As compared to the other treatments, the control group had considerably higher body weights, weight growth, feed intake, and feed conversion ratio. Ginger powder use was shown to have a detrimental impact on growth in this investigation.
There have been many advances in the solar chimney power plant since 1930 and the first pilot work was built in Spain (Manzanares) that produced 50 KW. The solar chimney power plant is considered of a clean power generation that needs to be investigated to enhance the performance by studying the effect of changing the area of passage of air to enhance the velocity towards the chimney to maximize design velocity. In this experimental and numerical study, the reduction area of solar collector was investigated. The reduction area that mean changing the height of glass cover from the absorbing plate (h1=3.8cm, h2=2.6cm and h3=1.28cm). The numerical study was performed using ANSYS Fluent software package (version 14.0) to solve go
... Show MoreThe limitations of conventional cement mortar as a widely used construction material include low tensile capacity, high permeability, and susceptibility to chemical degradation. The increasing demand for durable and sustainable construction materials has led to increased attention in modifying cementitious materials through nanotechnology. This study investigates the influence of nano-silica (NS) and nano-alumina (NA) on the physical, strength-related, and durability characteristics of cement mortar to determine the optimum nanomaterial type and dosage for performance enhancement. Six mortar mixes, in addition to a reference mix, were designed and prepared by adding 1%, 1.5%, and 2% of the cement weight with NS and NA separately, an
... Show MoreThe double-skin profiled composite wall (DSPCW) system, filled with concrete material, is favorable in modern structures due to its high strength and ductility. Openings may be required within this composite wall (DSPCW) for various reasons, similar to a conventional bearing wall, which can lead to a reduction in bearing capacity. Therefore, to avoid changes in the geometry, materials, and thickness of this DSPCW wall, a new internally stiffening concept has been suggested by providing embedded cold-formed steel tube (CFST) columns. For this purpose, two full-scale DSPCW specimens were tested under static axial load, one of which was fabricated with a large opening size and stiffened with two octagonal CFST columns, while the other
... Show MoreIn this work, an anti-reflection coating was prepared in the region (400-1000) nm of wavelength, with a double layer of silicon dioxide (SiO2) as an inner layer and the second layer of the mixture (SiO2) and titanium dioxide (TiO2) with certain ratios, as an outer layer using the chemical spraying method with a number of 6 sprays of layer SiO2 and 12 sprays of layer SiO2 - TiO2. Using the method of chemical spraying deposited on the glass as a substrate with a different number of sprays of SiO2, and a fixed number of TiO2-SiO2. The optical and structural properties were determined using UV-Vis spectroscopy and atomic force mi
... Show MoreThis work presents an innovative approach to enhancing the performance of concrete with reclaimed asphalt pavement (RAP) aggregates using titanium dioxide (TiO2) nanoparticles. Traditional limestone coarse aggregates were partially replaced with 30% and 50% RAP aggregates; a subset of mixtures containing RAP aggregates was treated with TiO2 nanoparticles. The rheological, mechanical, and long-term properties of concrete, along with changes in its chemical composition following the addition of RAP and TiO2, were evaluated. Results revealed that using 30% and 50% RAP in concrete mixtures reduced their compressive strength by 18% and 27%, respectively. However, using TiO2 in those mixtures enhanced their compressive strength by 8.7% an
... Show MoreThis study explores the role of nanomaterials in the performance of asphalt binders and mixtures. Two commonly available nanomaterials, i.e., nanosilica (NS) and nanoalumina (NA), were used at contents of 0%, 2%, 4%, 6%, and 8% by weight of asphalt binder. A set of experiments was carried out at the binder level to investigate properties such as penetration, softening point, aging-related mass loss, nanomaterial dispersion (storage stability), and workability (rotational viscosity). In addition, the suitability of NS and NS was also assessed through the testing of nanomodified asphalt mixtures, which focused on Marshall properties, the resilient modulus, moisture susceptibility, permanent deformation, and fatigue resistance. The findings in
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Abstract
This current research aims to make theoretical frame for the thoughts and principle knowledge for high performance work system ،also trying to know the role that high performance work system practices which is (Effective staffing، comprehensive training، providing work career، and employee participation) play to enhance the organization effectiveness ، although knowing the principles of high performance work system which is: (Shared Information، Knowledge Development Performance and Reward linkage Egalitarianism)and its effect on the organizations. As well as defining the special concept of High performance wo
... Show MoreSilver-bismuth iodide (ABI) ternary semiconductors, such as AgBi2I7, AgBiI4, Ag2BiI5, and Ag3BiI6, have emerged as promising lead-free light absorbers for photovoltaic applications due to their favorable optoelectronic properties. Despite recent advances that have improved power conversion efficiencies from ∼1% to over 5%, ABI-based solar cells still show substantial open-circuit voltage (VOC) losses of up to ∼1 V, which significantly hinder the device performance. These losses have been experimentally attributed to the non-radiative recombination originating from intrinsic defects, however, theoretical understanding of these defect mechanisms remains limited. Here, using density functional theory calculations, we systematical
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