Abstract:-

            The approach maintenance and replacement one of techniques of operations research whom cares of the failure experienced by a lot of production lines which consist of a set of machines and equipment, which in turn exposed to the failure or work stoppages over the lifetime, which requires reducing the working time of these machines or equipment below what can or conuct  maintenance process once in a while or a replacement for one part of the machine or replace one of the machines in production lines. In this research is the study of the failure s that occur in some parts of one of the machines for the General Company for Vege

        يمر عالمنا المعاصر اليوم بمرحلة من التطور والتغيير السريعين لم يسبق له أن مر بهما فـي تاريخ البشرية ، ويشمل مظاهر الحياة  الأنسانية  والأقتصادية والعلمية والتربويـة والنفسية وغير ذلك . وتختلف سرعة هذا التغيير من مجتمع الـى مجتمع آخر , وأدى هذا الى تراكم كميات كبيرة من المعلومات .

         لقد أكد الكثير مـن التربويين أن التطور التكنولوجي فـي ال

هدفت هذه الدراسة إلى تحليل نتائج الاختبار الوطني الموحد الذي تطبقه وزارة التربية والتعليم الفلسطينية في مادة الرياضيات لطلبة الصف الثامن الأساسي في المدارس الحكومية في محافظة طولكرم، وذلك لمعرفة مستوى الطلبة على هذا الاختبار في ضوء متغيرات الجنس والمنطقة التعليمية ونوع المدرسة، ومعرفة علاقة التحصيل على هذا الاختبار بتحصيل الطلبة المدرسي والمعدل العام. ولتحقيق ذلك تم تحليل درجات (3218) طالباً وطالبة؛ وهم ي

The aim of the research is to know the effect of a training program based on interactive teaching strategies on achievement and creative problem solving among fourth-grade students in chemistry of the directorate of education Rusafa first, the sample was divided into two groups, one experimental and numbering (29) students and the other control group numbering (30) students. The experimental group underwent the training program in the first semester of the year (2021-2022) and the control one studied according to the usual method. Two tools were built, the first being an academic achievement test consisting of (40) multiple-choice items, and the second a test of creative problem-solving skills in a chemistry subject and consisting o

تهدف الدراسة الحالية إلى معرفة أثر استخدام نموذج ويتلي في اكتساب طلاب الصف الثاني الأساسي لمادة قواعد اللغة العربية. وللتحقق من هدف الدراسة فرضت الفرضيات الصفرية الآتية: الفرضية الصفرية الأولى هي (لا توجد فروق ذات دلالة إحصائية عند مستوى (0.05) بين متوسط ​​درجات المجموعة التجريبية التي درست مادة قواعد اللغة العربية وفق نموذج ويتلي ومتوسط ​​درجات المجموعة الضابطة التي درست مادة قواعد اللغة العربية وفق الطريق

The objective of this research is to identify the effect of Using Fryer strategy on achievement and systemic thinking in the subject of chemistry of second class intermediate school students. The sample of research consisted of 59 students in one intermediate school in Baghdad/Iraq, split into two groups; experimental and control. The scientific material of the study is related to Chapters II and III of the Science Book for the second Intermediate School for the Year (2019-2020). The scientific test is composed of 25 test items whilst the second instrument for research related to systematic thinking test consisted of 12 items. The results of the research showed that the use of Fryer's chemistry-teaching strategy has increased achievement an

The objective of this research is to identify the effect of Using Fryer strategy on achievement and systemic thinking in the subject of chemistry of second class intermediate school students. The sample of research consisted of 59 students in one intermediate school in Baghdad/Iraq, split into two groups; experimental and control. The scientific material of the study is related to Chapters II and III of the Science Book for the second Intermediate School for the Year (2019-2020). The scientific test is composed of 25 test items whilst the second instrument for research related to systematic thinking test consisted of 12 items. The results of the research showed that the use of Fryer's chemistry-teaching strategy has increased achieve

The efficiency of Nd:YAG laser radiation in removing debris and smear layer from prepared root
canal walls was studied. Fifty-seven human extracted single rooted anterior teeth were divided into three
groups. A group that was not lased is considered as a control group. The remaining teeth were exposed to
different laser parameters regarding laser energy, repetition rate and exposure time. For the case of the set of
parameters of 7 mJ laser energy, the cleaning was maximum at 3 p.p.s. repetition rate for 3 seconds exposure
time for, the coronal, middle and apical thirds. Above and below this energy level, there was an overdose
(melting) or under dose (no effect). Nevertheless for 10mJ laser energy case, the cleaning effi

The present study aimed to impact Strategy mental map in the acquisition of geographical concepts at the fifth-grade students in the literary geography classes. To achieve the objectives of the research formulated researcher null hypothesis (no statistically significant difference at the level (0.05) between the average scores of students who Adersna using a mind map, and who Adersna using the method usual in the acquisition of concepts geographic fifth grade literary). Has chosen researcher design Altjeribeachtar researcher Design The partial adjustment for both experimental and control groups Pachtearlakedzab concepts. The sample Seateetmthel graders secondary schools under the Directorate General of Educational Baghdad Rusafa II has c