من خلال ملاحظة الباحثتين الميدانية لمستوى الأداء الفني لمنتخب ناشئات القطر بالجمناستك لمهارة قفزة اليدين الأمامية على جهاز منصة القفز الحديثة لاحظن وجود مشكلة تكمن في ضعف هذا الأداء والذي يؤثر على بعض المتغيرات البيوكينماتيكية لهذه المهارة مما يؤدي إلى عدم أداء المهارة بالشكل الصحيح ، وتعزو الباحثتان ذلك الضعف إلى قلة الدفع بالرجلين والذراعين . لذا ارتأت الباحثتان إجراء هذا البحث الذي يهدف إلى تنمية القوة الانفجارية باستخدام تدريبات الأثقال بطريقة الصعود والهبوط للتعرف على تأثيرها في تحسين بعض المتغيرات البيوكينماتيكية والأداء الفني لمهارة البحث المختارة ، وكان من أهداف البحث التعرف على تأثير استخدام هذه التدريبات في تنمية القوة الانفجارية لدى اللاعبات ، وقد افترضت الباحثتان عدة فروض كان منها إن هنالك فروقاً ذات دلالة إحصائية بين نتائج التقويمين القبلي والبعدي نتيجة تنمية القوة الانفجارية باستخدام تدريبات الأثقال بطريقة الصعود والهبوط ولصالح التقويم البعدي ، وعليه كان المنهج المستخدم في البحث هو المنهج التجريبي وشملت عينة البحث لاعبات منتخب ناشئات القطر بالجمناستك بأعمار ( 10 – 12 سنة ) والبالغ عددهن ( 6 لاعبات ) ، وقد استغرق تطبيق المنهج التدريبي ( 3 أشهر ) بواقع ( 3 وحدات ) أسبوعياً أي بمجموع ( 36 ) وحدة تدريبية طوال مدة البحث ، وقد استنتجت الباحثتان عدة استنتاجات كان من أهمها أن التدريب بالأثقال بطريقة الصعود والهبوط يؤدي إلى تنمية القوة الانفجارية وان تنمية القوة الانفجارية يؤدي إلى تحسين بعض المتغيرات البيوكينماتيكية والأداء الفني لمهارة البحث المختارة .
The microdrilling and nanodrilling holes are produced by a Q-switched Nd :YAG laser (1064 nm) interaction with 8009 Al alloy using nanoparticles. Two kinds of nanoparticles were used with this alloy. These nanoparticles are tungsten carbide (WC) and silica carbide (SiC). In this work, the microholes and nanoholes have been investigated with different laser pulse energies (600, 700 and 800)mJ, different repetition rates (5Hz and 10Hz) and different concentration of nanoparticles (90%, 50% and 5% ). The results indicate that the microholes and nanoholes have been achieved when the laser pulse energy is 600 mJ, laser repetition rate is 5Hz, and the concentration of the nanoparticles (for the two types of n
... Show MoreThe accurate extracting, studying, and analyzing of drainage basin morphometric aspects is important for the accurate determination of environmental factors that formed them, such as climate, tectonic activity, region lithology, and land covering vegetation.
This work was divided into three stages; the 1st stage was delineation of the Al-Abiadh basin borders using a new approach that depends on three-dimensional modeling of the studied region and a drainage network pattern extraction using (Shuttle Radar Topographic Mission) data, the 2nd was the classification of the Al-Abiadh basin streams according to their shape and widenings, and the 3rd was ex
... Show Moreيهدف البحث ابر تحديد نقاط الاختناق من خلال تحديد القيود التي تعترض عمل الشركة وبالتالي معالجتها من خلال تطبيق خطوات نظرية القيود والتي تمثل اداة فاعلة تساعد في التخلص من نقاط الاختناق وجدولة تلك القيود
The relation between the output power and wavelengths for a 532nm 3W frequency doubled diode pumped solid state laser pumped Ti:Sapphire crystal is investigated. A 20 femtosecond pulse at 800 nm is obtained. A 320 mW is found to be the highest power at 800nm. Below this wavelength value and above the power was found to deviate from highest output value.
One of the serious problems in any wireless communication system using multi carrier modulation technique like Orthogonal Frequency Division Multiplexing (OFDM) is its Peak to Average Power Ratio (PAPR).It limits the transmission power due to the limitation of dynamic range of Analog to Digital Converter and Digital to Analog Converter (ADC/DAC) and power amplifiers at the transmitter, which in turn sets the limit over maximum achievable rate.
This issue is especially important for mobile terminals to sustain longer battery life time. Therefore reducing PAPR can be regarded as an important issue to realize efficient and affordable mobile communication services.
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Abstract: Recently, there is increasing interest in using mode-division multipelexing (MDM) technique to enhace data rate transmission over multimode fibers. In this technique, each fiber mode is treated as a separate optical carrier to transfer its own data. This paper presents a broadband, compact, and low loss three-mode (de)multiplexer designed for C+L band using subwavelength grating (SWG) technology and built-in silicon-on-insulator SOI platform. SWG offers refractive index engineering for wider operating bandwidth and compact devices compared to conventional ones. The designed (de)multiplex deals with three modes (TE0, TE1, and TE2) and has a loss > -1 dB and crosstalk < −15 dB, and its operation c
... Show MoreRecurrent strokes can be devastating, often resulting in severe disability or death. However, nearly 90% of the causes of recurrent stroke are modifiable, which means recurrent strokes can be averted by controlling risk factors, which are mainly behavioral and metabolic in nature. Thus, it shows that from the previous works that recurrent stroke prediction model could help in minimizing the possibility of getting recurrent stroke. Previous works have shown promising results in predicting first-time stroke cases with machine learning approaches. However, there are limited works on recurrent stroke prediction using machine learning methods. Hence, this work is proposed to perform an empirical analysis and to investigate machine learning al
... Show MoreEvaluation is one of the most important elements of teaching process. The recent trends in evaluation and educational reform movements have called for using alternative evaluation, which focuses on performance evaluation. Authentic assessment is usually described as formative, in which students participate in their acquisition, in addition to the fact that students are productive and active, which is reflected in the students' achievement and skill level. The study aims to reveal the degree of knowledge and use of alternative assessment tools by primary school teachers in Gaza -Palestine. To meet the objective of the study, the researchers used the descriptive-analytical method and the questioner as a study tool. The study sample c
... Show Moreتحضيروتشخيص ودراسة طيفية وحرارية وبيولوجية للمركب الجديد والمشتق من 2-امينوبينزوثايوزول واستخدامه كمثبط لتأكل سبيكة (-brass) في أنابيب مياه الشرب مع بعض المعقدات الفلزية
The present study was carried out to investigate the effect of oral administration of hot aqueous extract of beetle cocoon Larinus maculatus Faldermann, in a two doses 50 and100mg/Kg/Bw for 25 and 45days respect- tively on some organs such as liver, lung, kidney, intestine, heart, spleen, and brain in male mice Mus musculus. The results indicated that there were toxicopathological changes in many tissues of experimental animals. Histo -pathological changes was dose and period dependent . It was found that the aqueous extract of beetle cocoon has undesirable effect at the administered doses, since the raw extract of this cocoon is currently being used in Folk medicine as treatment for cough, bronchitis in Iraq. This study revealed that the l
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