This research introduces a developed analytical method to determine the nominal and maximum tensile stress and investigate the stress concentration factor. The required tooth fillets parametric equations and gears dimensions have been reformulated to take into account the asymmetric fillets radiuses, asymmetric pressure angle, and profile shifting non-standard modifications. An analytical technique has been developed for the determination of tooth weakest section location for standard, asymmetric fillet radiuses, asymmetric pressure angle and profile shifted involute helical and spur gears. Moreover, an analytical equation to evaluate gear tooth-loading angle at any radial distance on the involute profile of spur and helical gears, (taking into account the effect of profile shift factor) has been derived. In addition, numerical solution for the evaluation of the maximum fillet tensile stress and the combined tensile stress concentration factor for the verification of the analytical method using computer-aided engineering software (ANSYS Version 18.1). The analytical and FE result have been compared and found to be very close. The most effective method for reducing the stress concentration factor have been found by applying negative profile shifting on asymmetric tooth with lower unloaded pressure angle and high loaded pressure angle and fillet radius, which can lead to an enhancement percentage of (20%) when using a (35o/20o) asymmetric spur gear of a (24) teeth number with a shift factor of (-0.3mo) compared with standard (20o) one.
A field experiment was carried out at University of Baghdad, College of Agricultural Engineering Sciences during fall season of 2020 and spring season of 2021. This study was aimed evaluate the effect of the organic fertilizer and boron foliar on the yield of potatoes for processing. The factorial experiment (5*4) within RCBD and three replicates. The organic fertilizer as palm peat at four levels (0, 12, 24 and 36 ton. ha-1) in addition to the chemical fertilizer recommendation treatment. Boron at four Concentrations 0, 100, 150 and 200 mg. L-1 . The results revealed significant different among application of organic fertilizer at the level of 24 ton. ha-1 and the foliar application of boron at a concentration of 100 mg. L-1 in the
... Show MoreBackground: The disc prolapse is a common condition especially in young adults. Different levels are affected in the lumber region; the L4/L5 disc is more susceptible to longitudinal load and is the most common site of lumbar disc prolapse. The L5/S1 disc is protected from torsion load by strong ilio-lumbar ligaments but it is more susceptible to axial compressive forces. Many factors affect the result and outcome of surgery in these levels.Objective: The aim of this study is to correlate operative data, short-term results, complications, and prognostic factors (age, gender, mobility, hospital stay, and level of pain) for one-level lumber discectomybetween different levels (L4–L5 vs. L5–S1).Methods In this prospective study, 32 patie
... Show MoreThis research aim to exploring the positive psychological capital concept (PsyCap) which drawn from positive psychology and applying it at workplace. PsyCap emerged as extending for recent another types of capital, such as human capital and social capital. It has been defined as “an individual’s positive psychological state of development". The PsyCap consist of four core constructs (self- efficacy, optimism, hope, and resilience). Each of the four components has considerable theorizing and researching that can contribute to developing an integrative theoretical foundation for PsyCap. But their combined motivational effects will be broader and more impactful than any one of t
... Show MoreA simple analytical method was used in the present work for the simultaneous quantification of Ciprofloxacin and Isoniazid in pharmaceutical preparations. UV-Visible spectrophotometry has been applied to quantify these compounds in pure and mixture solutions using the first-order derivative method. The method depends on the first derivative spectrophotometry using zero-cross, peak to baseline, peak to peak and peak area measurements. Good linearity was shown in the concentration range of 2 to 24 μg∙mL-1 for Ciprofloxacin and 2 to 22 μg∙mL-1 for Isoniazid in the mixture, and the correlation coefficients were 0.9990 and 0.9989 respectively using peak area mode. The limits of detection (LOD) and limits of quantification (LOQ) wer
... Show Moreالذات والتحصيل الدراسي . وقد استخدمت الباحثة المنهج الوصفي التحليلي، وبلغت عينة الدراسة (500) طالبًا وطالبة، تم اختيارهم بالطريقة الطبقية العشوائية وهي تمثل (15%) من مجتمع الدراسة البالغ (3328) طالباً وطالبة من طلبة المرحلة الإعدادية واستخدمت الباحثة مقياسين تم بناء مقياس لقياس الجوهر والمظهر وتبني مقياس فاعلية الذات بعد إن قامت بترجمته وتعريبه وجعله ملائم للبيئة العراقية، كم تم استخراج درجات التحصيل الدراسي للع
... Show MoreRheumatoid arthritis and periodontitis use analogous effector destructive procedures, in that the inflammatory cells and pro-inflammatory cytokines that drive chronic bone erosion in RA and chronic periodontal destruction in Periodontitis are alike. Periodontitis (PD) has appeared as a hazard factor in a number of health situations as rheumatoid arthritis (RA). To determine the effect of anti-tumor necrosis factor alpha biological treatment (methotrexate and Enbrel or infliximab) on periodontal status of patients having rheumatoid arthritis with periodontitis in comparison to those having periodontitis without rheumatoid arthritis and control healthy subjects and to determine the serum levels of anti-cyclic citrullinated peptide (ACCP) in t
... Show MoreAny design subject to a set of forces contributing to the establishment of relations working to strengthen the internal elements of the design; any imbalance in these elements can make a fragmented and weak design, thus preventing it from achieving the goal or performance. Poor performance can be attributed to various factors: the extent and function of the elements and principles in the design, realization of the idea, especially in fashion design.
Moreover, there are many aspects of a design that go into achieving the realization of the designer’s idea. The design utilizes a lot of stimulants by drawing attention to its design, which is consistent with the need for psychological and material individuals. In this research, we will
The process of transporting waste from urban areas to sanitary landfill sites requires large amounts of money due to the length and distance. To address this problem, temporary transfer stations were established by the Municipality of Baghdad to reduce the cost of transportation, and for the purpose of preserving the environment in a sustainable manner, standards were set for the establishment of these stations. The two stations of Al-Karrada Municipality and Al-Shula Municipality were chosen as a case study to measure the extent of adopting and applying the standards for establishing substations locally, regionally and internationally, and the most important results were reached Which is that the transforming (regular) stations of the t
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