ان شركات التأمين وبسبب طبيعة نشاطها التأميني تتجمع لديها أموال ضخمة عن الأقساط التي تحصلها من المؤمن لهم, ولغرض عدم ترك هذه الاموال عاطلة, فأنه يتم استثمارها في مجالات وأدوات استثمار متنوعة لتحقيق عوائد منها. هذا ولغرض تحديد وتوجيه هذه الاموال في مجال أو أداة الاستثمار المناسبة أو تحديد مدى جدوى هذه الاستثمارات, فانه يتم تقييمها, وهناك عدة نماذج رياضية لتقييم بدائل الاستثمار في شركات التأمين, إلا أنه لا
... Show Moreيقدم هذا البحث الانموذج الرمادي GM(1,1) من الرتبة الأولى و بمتغير واحد و هو أساس نظرية النظام الرمادي تناول هذا البحث خصائص الانموذج الرمادي ومجموعة من طرائق تقدير معالم الانموذج الرمادي GM(1,1) وهي طريقة المربعات الصغرى (LS) , طريقة المربعات الصغرى الموزونة (WLS) , طريقة المربعات الصغرى الكلية (TLS) و طريقة الانحدار التدريجي (DS) حيث تمت المقارنة بين هذه الطرق اعتمادا على نوعين من المقاييس متوسط مربع الخطأ MSE))
... Show Moreهدف البحث الى اعداد تمرينات super site)) للاعبي الريشة الطائرة فئة الشباب ، ومعرفة تأثير التمرينات على بعض المؤشرات الفسيولوجية ومهارة الضربة الساحقة لدى لاعبي الريشة الطائرة فئة الشباب ، وتم تحديد مجتمع البحث من لاعبي الريشة الطائرة فئة الشباب لنادي الارمني وتم اختيار عينة البحث بالطريقة العمدية (8) لاعبين بالريشة الطائرة من النادي الارمني واستخدمت الباحثتان المنهج التجريبي ذو الاختبار القبلي والبعدي .ويهدف ال
... Show MoreWheat straw was modified with malonic acid in order to get low cost adsorbent have a good ability to remove copper and ferric ions from aqueous solutions, chemical modification temperature was 120°C and the time was 12 h. Parameters that affect the adsorption experiments were studied and found the optimum pH were 6 and 5 for copper and iron respectively and the time interval was 120 min and the adsorbent mass was 0.1 g. The values for adsorption isotherms parameters were determined according to Langmuir [qmax were 54.64 and 61.7 mg/g while b values were 0.234 and 0.22 mg/l] , Freundlich [Kf were 16.07 and 18.89 mg/g and n were 2.77 and 3.16], Temkin [B were 0.063 and 0.074 j/mol and At were 0.143 and 1.658 l/g] and for Dubinin-Radushkev
... Show MoreFlow-production systems whose pieces are connected in a row may not have maintenance scheduling procedures fixed because problems occur at different times (electricity plants, cement plants, water desalination plants). Contemporary software and artificial intelligence (AI) technologies are used to fulfill the research objectives by developing a predictive maintenance program. The data of the fifth thermal unit of the power station for the electricity of Al Dora/Baghdad are used in this study. Three stages of research were conducted. First, missing data without temporal sequences were processed. The data were filled using time series hour after hour and the times were filled as system working hours, making the volume of the data relativel
... Show MoreIn the current work various types of epoxy composites were added to concrete to enhance its effectiveness as a gamma- ray shield. Four epoxy samples of (E/clay/B4C) S1, (E/Mag/B4C) S2, (EPIL) S3 and (Ep) S4 were used in a comparative study of gamma radiation attenuation properties of these shields that calculating using Mont Carlo code (MCNP-5). Adopting Win X-com software and Artificial Neural Network (ANN), µ/ρ revealed great compliance with MCNP-5. By applying (µ/ρ) output for gamma at different energies, HVL, TVL and MFP have been also estimated. ANN technique was simulated to estimate (µ/ρ) and dose rates. According to the results, µ/ρ of all epoxy samples scored higher than standard concrete. Both S2 and S3 samples having h
... Show MoreABSTRACT
In this research been to use some of the semi-parametric methods the based on the different function penalty as well as the methods proposed by the researcher because these methods work to estimate and variable selection of significant at once for single index model including (SCAD-NPLS method , the first proposal SCAD-MAVE method , the second proposal ALASSO-MAVE method ) .As it has been using a method simulation time to compare between the semi-parametric estimation method studied , and various simulation experiments to identify the best method based on the comparison criteria (mean squares error(MSE) and average mean squares error (AMSE)).
And the use
... Show MoreAn experimental and theoretical study has been done to investigate the thermal performance of different types of air solar collectors, In this work air solar collector with a dimensions of (120 cm x90 cm x12 cm) , was tested under climate condition of Baghdad city with a (43° tilt angel) by using the absorber plate (1.45 mm thickness, 115 cm height x 84 cm width), which was manufactured from iron painted with a black matt.
The experimental test deals with five types of absorber:-
Conventional smooth flat plate absorber , Finned absorber , Corrugated absorber plate, Iron wire mesh on absorber And matrix of porous media on absorber .
The hourly and average efficiency of the collectors
... Show MoreThe effect of different Ti additions on the microstructure of Al-Ti alloy prepared by powder metallurgy was investigated. A certain amount of Ti (10wt%, 15wt%, and 20wt%) were added to aluminium and the tests like microhardness, density, scanning electron microscope (SEM), optical microscope (OM) and X-Ray Diffraction (XRD) were conducted to determine the influence of different Ti additives on the Al-Ti alloy properties and microstructure. The results show that the grains of α-Al changed from large grains to roughly spherical and then to small rounded grains with increasing Ti content, the micro-hardness of the alloy increases with increasing Ti, and XRD results confirm the formation of TiAl3 intermetallic co
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