The present work aimed to examine the nature and degree of the cross-correlations among three different ionospheric indices: these are Optimum Working Frequency (OWF), Highest Probable Frequency (HPF), and Best Usable Frequency (BUF). VOCAP and ASASPS models were adopted to determine the datasets of the selected ionospheric indices. The determination was made for different transceiver stations that provide certain HF connection links during the minimum and maximum years of solar cycle 24, 2009 and 2014, respectively. Matlab program was implemented to produce the geodesic parameters for the selected transceiver stations. The determination was made for different path lengths (500, 1000, 1500, and 2000) Km and bearings (0o, 45o, 90o ........ 315o). Different correlation methods were used to examine the best determination coefficient values between the tested parameters. A third-order polynomial equation was set as the best correlation method that gave a better description for the correlation among the tested parameters. The proposed mathematical correlation equations were used to predict the seasonal values of the (HPF, OWF and BUF) parameters. The proposed equations were verified by comparing their values with the observed datasets during the study years. Also, the predicted values were tested using different statistical methods, which gave good results for all tested cases. يهدف العمل الحالي إلى دراسة طبيعة ودرجة الترابط بين ثلاثة مؤشرات آيونوسفيرية مختلفة وهي (HPF,OWF and BUF), تم استخدام نماذج VOCAP و ASASPS لحساب قيم البيانات للمؤشرات الآيونوسفيرية المختارة. اجريت الحسابات لمحطات الإرسال / الاستقبال المختلفة التي توفر روابط اتصال عالية التردد خلال سنوات الصغرى والعظمى للدورة الشمسية 24 (2009 و 2014) على التوالي. تم تنفيذ برنامج Matlab لايجاد قيم المعلمات الجيوديسية لمحطات الإرسال / الاستلام لأطوال مسافات مختلفة (500، 1000، 1500 و 2000) كم واتجاهات مختلفة(0o, 45o, 90o ........ 315o). تم تطبيق طرق ارتباطية مختلفة لاختبار افضلها بين المعاملات المختبرة . تم اقتراح معادلات رياضية متعددة الحدود (الدرجة الثالثة) كأفضل طريقة تصف القيم الارتباطية بين المعاملات المحددة لغرض الدراسة. تمكنت المعادلات المقترحة من التنبؤ بالقيم الموسمية للمؤشرات ((HPF و(OWF) و (BUF).و تم التحقق منها من خلال مقارنتها مع قيم المعلمات المرصودة خلال سنوات الدراسة . كما تم اختبار القيم المتوقعة باستخدام طرق إحصائية مختلفة والتي قدمت نتائج جيدة لجميع الحالات المختبرة
The structural, optical and photoelectrical properties of fabricated diffusion heterojunction (HJ) solar cell, from n-type c-Si wafer of [400] direction with Boron, has been studied. AgAl alloys was used because of its properties that affect as a good connection materials. TiO2 has been used as a reflecting layer to increase the absorption radiation. The HJ has direct allowed energy gap equal to 3.1 eV. The c-Si/B HJ solar cell yielded has an active area conversion efficiency of 16.4% with an open circuit voltage of (Voc) 0.592V, short circuit current (Isc) of 2.042mA, fill factor (F.F) of 0.682 and % =10.54.
Fabrication of solar cell prepared by thermal spray and vacuum thermal evaporation method on silicon wafer(n-type) and studying its efficiency. The film have been deposited on three layers(ZnO then CdS and CdTe) on Si and glass respectively.Direct energy gap was calculated and equal to (4.3,3.4,3)eV and indirect energy gap equal to (3.5,2.5,1.5)eV respectively . Efficiency was calculated for the cell of area 2cm2 it was equal to 0.14%.
In this paper, the solar surface magnetic flux transport has been simulated by solving the diffusion–advection equation utilizing numerical explicit and implicit methods in 2Dsurface. The simulation was used to study the effect of bipolar tilted angle on the solar flux distribution with time. The results show that the tilted angle controls the magnetic distribution location on the sun’s surface, especially if we know that the sun’s surface velocity distribution is a dependent location. Therefore, the tilted angle parameter has distribution influence.
Abstract
A new type of solar air heater was designed, fabricated, and tested in Baghdad, Iraq winter conditions. The heater consists of two main parts. The horizontal section was filled with the black colored iron chip while the vertical part has five pipes filled with Iraqi paraffin wax. A fan was fixed at the exit of the air. Two cases were studied: when the air moved by natural convection and when forced convection moved it. The studied air heater has proven its effectiveness as it heated the air passing through it to high temperatures. The results manifest that using little air movement makes the temperatures, stored energies, and efficiencies of the two studied cases converge
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In light of globalization and internationalization of financial markets, issues arising from financial crises have become increasingly serious and fundamental, creating a lot of debate among experts around the world. So, many studies have attempted to investigate what measures can be taken to detect and prevent crises before they devastate the economies.
Therefore, this paper examines the Effectiveness of the Monetary Policy (MP) to Avoid, Reduce or Treat the Financial Crisis in Malaysia. Scholars have yet to agree on the issue
... Show MoreThis study aimed to evaluate the preparedness and adherence of community pharmacists to the International Pharmaceutical Federation (FIP) Health Advisory COVID-19 guidelines for pharmacists (July 2020) during COVID-19 pandemic. This was a cross-sectional study based on electronic survey using google form, which was distributed from November 19, 2020 to January 1, 2021 using social media platforms. The survey measured 21 pharmacy preventive measures (PM). A multivariate regression analysis was used to identify factors influencing pharmacy implementing of PM. Hand disinfection after serving patients represented the main adopted measure (89.3%). Surprisingly, only 35.4% of participants implemented the proper ways of hand disinfection during fa
... Show MoreThis study aims to suggest a technique for soil properties improvement of AL- Kadhimin shrine Minaret and to support the foundation, which has a tilt of roughly 80 cm from the vertical axis. The shrine of the AL- Kadhimin is made up of four minarets with two domes set in a large courtyard. The four minarets have skewed to varying degrees due to uncontrolled dewatering inside the shrine in recent years. However, the northeast minaret was the most inclined due to its proximity to the well placed inside shrine courtyard. When the well near the minaret is operated, the water level drops, increasing the effective stresses of the soil and causing differential settling of the minaret foundation. To maintain the minaret's foundation from potenti
... Show MoreBackground: Osteoporosis affects almost all of the bones in the female body; the most important one in the facial bone is mandible. Menopause is defined as an absence of the menses for one year. During this time, estrongen, progesterone and ovarian androgens production are diminished due to adult onset ovarian failure which leads to osteoporosis. This study aimed to evaluate the use of computed tomography mandibular morphometric indices for the assessment of pre and postmenopausal osteoporotic women. Subjects and material: This study conducted on 50 Iraqi females divided into 2 groups 20 -30years old as a control group and over50 years old as a study group attending Al-Karkh hospital, Department of Computed Tomography.(each group25 female).
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