In this research the natural frequency of a cracked simple supported beam (the crack is in many places and in different depths) is investigated analytically, experimentally and numerically by ANSYS program, and the results are compared. The beam is made of iron with dimensions of L*W*H= (0.84*0.02* 0.02m), and density = 7680kg/m3, E=200Gpa. A comparison made between analytical results from ANSYS with experimental results, where the biggest error percentage is about (7.2 %) in crack position (42 cm) and (6 mm) depth. Between Rayleigh method with experimental results the biggest error percentage is about (6.4 %) for the same crack position and depth. From the error percentages it could be concluded that the Rayleigh method gives close results to experimental than ANSYS. Also it is found that the frequency of beam when the crack is in the middle position is less than the frequency with crack near the end position.
افرض ان (X1, X2, …. , Xn) هي عينة عشوائية من توزيع له دالة احتمالية الكثافة . المثال المعتاد في مثل هكذا تقدير للامكان الاعظم (MLE) هو ليس وحيد باخذ ليكون كثافة منتظمة عليه، مثل .
انظر [Bicked and Doksum (1977, P111)] او [Hogg and Craig (1978, P(207)] بالاضافة الى احضار بعض الامور غير الطبيعية.
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This work includes design, implementation and testing of a microcontroller – based spectrum analyzer system. Both hardware and software structures are built to verify the main functions that are required by such system. Their design utilizes the permissible and available tools to achieve the main functions of the system in such a way to be modularly permitting any adaptation for a specific changing in the application environment. The analysis technique, mainly, depends on the Fourier analysis based methods of spectral analysis with the necessary required preconditioning processes. The software required for waveform analysis has been prepared. The spectrum of the waveform has been displayed, and the instrument accuracy has been checked.
... Show Moreالطائفية وتداعياتها على بناء الدولة العراقية المعاصرة
The globalization concept is regarded one of the modern concept which had seen in the last time while it hadn’t occur now only, but it had seen clearly with the technology &information revolution beside the quick development in the communication net which had made the world like a small village .
Since accounting is regarded business language based on integrated theoretical framework consists of many connected objective & rules which led to consistent accounting standards .
So with this development there is a clear need to consolidate the concepts , policies ,and applications which the companies use it in treating its financial events .
التكتلات الاقتصادية العالمية وانعكاساتها على الدول النامية
شهد العصر الحالي سرعة فائقة في انتاج وسائل الاتصال لاسيما في حقل الاتصال الاليكتروني وتوضح ذلك عبر الاندماج بين ظاهرة الكم الهائل من المعلومات وتعدد الوسائل الاتصالية وذلك لتحقيق الهدف المنشود لبث الرسالة الاتصالية الا وهو التفاعل من اجل التأثير في الفرد ومن ثم المجتمع ككل , فيما اضحت العلاقات العامة احد العوامل المؤثرة في عملية التغيير الاجتماعي بما تستند اليه من ممارسات تضعها في اطار الوظائف المجتمعية ال
... Show MoreAdenosine deaminase (ADA; Ec: 3.5.4.4), 5´- Nucleotidase (5´– NT; Ec: 3.1.3.5), and AMP – amino hydrolase (AMP – deaminase AMPDA; Ec: 3.5.4.6) activities were measured in sera of ovarian cancer patients before surgery, and after chemotherapy. The results indicated that ADA specific activity increased significantly (P<0.05), while 5´-NT and AMPDA specific activity decreased significantly (P<0.05) in ovarian cancer patients before surgery in comparison with those of their corresponding control women and benign tumors groups. When the activities of these enzymes were measured after chemotherapy, a significant decrease (P<0.05) in ADA activity, and a significant increase (P<0.05) in 5´- NT and AMPDA activities w
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Background: A minimally invasive antral membrane balloon elevation (MIAMBE) has been introduced to overcome the invasiveness of modified Caldwell-Luc (lateral approach) and the drawbacks of the osteotome (summers' technique) in maxillary sinus floor elevation surgery. Materials and methods: A total of 13 adult Iraqi patients aged 28-55 years, 4 males and 9 females underwent sinus floor elevation surgery via crestal approach by using sinus balloon technique. A panoramic radiograph and (Cone beam computed tomography (CBCT)/or medical CT scan) were obtained before and after surgery. Postoperative gained bone was assessed and the patient reactions including pain, nasal bleeding, and ecchymosis were recorded. The whole follow up period was 1yea
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(3)
This study was conducted to investigate the effect of feeding diets containing different levels of parsley on the hematological traits of local Iraqi geese. A total of twenty-four local geese, one year old, were used in this experiment. The birds were allocated into four treatment groups, consisting of six geese each. Treatment groups were: control diet (C) (free from parsley); T1: control diet + 80 g/d parsley; T2: control diet + 160 g/d parsley; and T3: control diet + 240 g/d parsley. At the end of the experiment, blood samples were obtained from all geese from the brachial vein by venipuncture. Hematological traits included in this study were red blood cells count (RBC), hemoglobin concentration (Hb), packed cell volume (PCV), mean cell
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(2)
