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 problem of the search (how to employ own aesthetic values sculpture prominent decorations doors in the holy shrines) as research aims to detect these formulas employed in relief sculpture in accordance with the aesthetic values of the decorations that add structure in the form of doors shrines dimensions of functional and aesthetic and expressive By selecting the general system configurations spaces for doors and select the components of the structural configurations decorative prominent types (geometric and floral and linear and composite) as well as identify the techniques adopted in the executive configurations doors at the level of raw materials and processors show. Find and define the beauty of decorative formations prominent of
... Show MoreThe aim of the research is to identify the imaginative thinking skills included in the content of the chemistry textbook for fifth-grade students in biological sciences at the preparatory stage, which is approved by the Ministry of Education, General Directorate of Curricula in the academic year 2020-2021. To achieve the objective of the study, the researcher depends on the previous studies in the field and content of imaginative thinking skills for preparing a list of skills that includes (3) essential skills and (11) sub-skills and (28) items related to all skills. The researcher adopted the analytical descriptive approach because of its appropriation of the goals of the research. Then the researcher analyzed the content of the book de
... Show MoreThe Imam Ibn al-Mundhir is likely in Shafi'i school. He has outlined some issues and disagreed with his doctrine. And that the vocabulary on which he relied on the weighting is correct and correct and I choose which I say. One of the most likely issues is the delay of Isha prayer to the darkness. And other issues simplified in the folds of research and study.
Background/objectives: To study the motion equation under all perturbations effect for Low Earth Orbit (LEO) satellite. Predicting a satellite’s orbit is an important part of mission exploration. Methodology: Using 4th order Runge–Kutta’s method this equation was integrated numerically. In this study, the accurate perturbed value of orbital elements was calculated by using sub-steps number m during one revolution, also different step numbers nnn during 400 revolutions. The predication algorithm was applied and orbital elements changing were analyzed. The satellite in LEO influences by drag more than other perturbations regardless nnn through semi-major axis and eccentricity reducing. Findings and novelty/improvement: The results demo
... Show MoreUltrasonic extraction is an inexpensive, simple and efficient alternative to conventional extraction techniques, as compared with other novel extraction techniques such as microwave-assisted extraction & supercritical fluid extraction techniques, the ultrasound apparatus is cheaper and its operation is easier. Ultrasound assisted extraction has risen rapidly in the latest decade, and for most applications it has proven to be effective compared to traditional extraction techniques. In this paper, a method of ultrasonic-assisted extraction was used to extract Inulin from tubers of Jerusalem artichoke, which have been reported to have several medicinal properties and uses. Inulin is a storage carbohydrate found in many plants especially
... Show MoreIn recent years, various methods have been developed to enhance the characteristics of asphalt pavement in order to face the continuous challenges of increasing traffic loads and changing climate conditions. One of the most popular and successful methods is modifying the asphalt mixtures or asphalt binder with the addition of polymers. Therefore, two types of Polyethylene (PE) polymer, High-Density PE (HDPE) and Low-Density PE (LDPE), are used in this research. Two methods were applied to prepare PE-modified asphalt mixtures: Semi-Wet Method (S-WM) and Dry Method (DM). The findings of the investigation indicated that the addition of PE polymer can reduce the wear loss of aggregate. In general, the experimental results revealed that asphalt
... Show MoreThis study aimed to assess orthodontic postgraduate students’ use of social media during the COVID-19 lockdown. Ninety-four postgraduate students (67 master’s students and 27 doctoral students) were enrolled in the study and asked to fill in an online questionnaire by answering questions regarding their use of social media during the COVID-19 lockdown. The frequency distributions and percentages were calculated using SPSS software. The results showed that 99% of the students used social media. The most frequently used type of social media was Facebook, 94%, followed by YouTube, 78%, and Instagram, 65%, while Twitter and Linkedin were used less, and no one used Blogger. About 63% of the students used elements of social media to l
... Show MoreLaboratory studies were carried out to investigate the differences between uninfested and infested bitter orange
Gypseous soils are considered one of the most problematic soils. The skirted foundation is an alternative technology that works to improve the bearing capacity and reduce settlement. This paper investigates the use of square skirted foundations resting on gypseous soil subjected to concentric and eccentric vertical load with eccentricity values of 4, 8, and 17 mm in 16 experimental model tests. To obtain the results by using this type of foundation, a small-scale physical model was designed to obtain the load–settlement behavior of the square skirted foundation; the dimension of the square footing is 100 mm × 100 mm with 1 mm thickness, the skirt depth (
ABSTRACT Background: Diabetes and periodontitis are complicated prolonged disorders through a recognized two-way association. There is elongated-conventional mark that hyperglycaemia in diabetes is affected on immune-inflammatory response and disturb the action of osteoclast and in balance bone turnover, which might rise the person vulnerability to the progress of prolonged periodontitis. Osteocalcin is one of the greatest plentiful matrix proteins originate in bones and produced absolutely there. Small osteocalcin crumbles are noticed in regions of bone remodeling and are in fact degradation products of the bone matrix, that is released outside cells into the Gingival Crevicular Fluid (GCF) and saliva after destruction of periodontal tissu
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