The effect of internal acoustic excitation on the leading-edge, separated boundary layers and the aerodynamic performance of NACA23015 cross section airfoil are examined as a function of excitation location with ranging frequency range (50-400) Hz of the introduced acoustic. Tests are separately conducted in two sections, open type wind tunnels at the Reynolds number of 3.3x105 for measurement at angle of attack (0, 3, 6, 9 &12) deg. and 3x104 for the visualization at angle of attack (12) deg. based on the airfoil chord. Results indicated that the excitation frequency and the excitation location are the key parameters to alter the flow properties and thus to improve the aerodynamic performance. The most effective excitation frequency is found to be equal to the shear layer instability frequency and on excitation location close to the separation point. Moreover, the lift is increased and drag reduced dramatically. The corresponding boundary layers are visualized to be reattached to the surface.
The aim of the present research is to know the following :
What are the Science and technology, society and environment issues (S.T.S.E) which included in the content of the chemistry Book third grade intermediate ?
And to achieve the objective of search The two researchers has prepares a list of science and technology, society and environment issues (STSE) consisted of (9) key issues namely ( Air quality and the atmosphere, sustainable development, water security, health and preventive security, mineral resources investment, pollution of various kinds, energy, food industry, production of weapons technology ) and from which (70) sub-issues emerge, Arbitrators competent agreement has been received . Then, the two re
... Show Moreان المشكلة البحثية تتحدد في ان المهام والادوات التي تملكها السلطة التنفيذية، من الصعوبة تركها من دون رقابة، والرقابة والتقييد ياتي من اطراف عدة، واهمها: السلطة التشريعية، فالبرلمان في العراق منح اختصاصات للنظر في اعمال واداء السلطة التنفيذية بما يضمن تقيدها بالدستور الاتحادي. والهدف من هذا البحث هو الاشارة الى اهمية الاختصاصات الممنوحة للبرلمان العراقي، بما يضمن التاسيس لدولة القانون، اي وجود مرجعية قانو
... Show MoreArtificial fish swarm algorithm (AFSA) is one of the critical swarm intelligent algorithms. In this
paper, the authors decide to enhance AFSA via diversity operators (AFSA-DO). The diversity operators will
be producing more diverse solutions for AFSA to obtain reasonable resolutions. AFSA-DO has been used to
solve flexible job shop scheduling problems (FJSSP). However, the FJSSP is a significant problem in the
domain of optimization and operation research. Several research papers dealt with methods of solving this
issue, including forms of intelligence of the swarms. In this paper, a set of FJSSP target samples are tested
employing the improved algorithm to confirm its effectiveness and evaluate its ex
Support vector machines (SVMs) are supervised learning models that analyze data for classification or regression. For classification, SVM is widely used by selecting an optimal hyperplane that separates two classes. SVM has very good accuracy and extremally robust comparing with some other classification methods such as logistics linear regression, random forest, k-nearest neighbor and naïve model. However, working with large datasets can cause many problems such as time-consuming and inefficient results. In this paper, the SVM has been modified by using a stochastic Gradient descent process. The modified method, stochastic gradient descent SVM (SGD-SVM), checked by using two simulation datasets. Since the classification of different ca
... Show Moreتعد الحروب أحد أخطر التهديدات في النظام العالمي; فهي تعد خرقا للقوانين والاعراف الدولية، والمبادئ الإنسانية، و من هنا تأتي دراسة أهمية موضوعنا الموسوم بـ (الاحتمالات المستقبلية للحرب الروسية – الأوكرانية و مدى انعكاسها على أمن دول شرق أوربا بعد العام 2022 ،)اذ يرتكز هذا البحث على دراسة واستعراض الاحتمالات المستقبلية )السيناريوهات) للحرب الروسية – الأوكرانية، والتي شنت من الحكومة الروسية بقيادة الرئيس الروس
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Sözlü Türk halk edebiyatı ürünleri içinde önemli yere sahip olan türlerden biri de atasözleridir. Atasözleri, nesilden nesile halk ağzında dolaĢan, kimin söylediği bilinmeyen, birtakım gerçekleri kısa ve öz bir Ģekilde ifade eden sözlerdir. Türk atasözleri Orhun Abideleri‟nde ilk kez karĢımıza çıkmakla birlikte, Uygur dönemi yazıtlarında ve özellikle Dîvânü Lûgati‟t Türk‟te geniĢ yer bulmuĢtur. Dilin anlatım ve kullanım imkânlarını geliĢtiren atasözlerine, dünyanın bütün dillerinde rastlanabilir. Bunun için, söyleyiĢte güzel, anlatımda güçlü, kavramda önemli unsurlar içeren kalıplaĢmıĢ sözler halinde bulunurlar. Bu çalıĢmada, Türk halk edebiyatında atas
In recent years, there has been expanding development in the vehicular part and the number of vehicles moving on the roads in all the sections of the country. Arabic vehicle number plate identification based on image processing is a dynamic area of this work; this technique is used for security purposes such as tracking of stolen cars and access control to restricted areas. The License Plate Recognition System (LPRS) exploits a digital camera to capture vehicle plate numbers is used as input to the proposed recognition system. Basically, the proposed system consists of three phases, vehicle license plate localization, character segmentation, and character recognition, the
... Show MoreThis study deals with the field of acieving the manuscripts of Islamic sciences by the great Imam ibn Kamal Pasha, but the mentioned book requires a great effort to explain what it contains of sciences, and to appear what it has contained
لطالما تُبنى قرارات الاستثمار في أسهم الشركات المدرجة في أسواق البورصة على خلفية المؤشرات المالية لها والتي عادةً مايتم إصدارها في نشرات سنوية معتمدة من قبل تلك الاسواق، إذ غالباً مايقوم المحللون الماليون بالاستعانه بها لتوجيه المستثمرين لإتخاذ القرارات المتعلقة بشراء أو بيع أسهم هذه الشركات.
لكنه على الرغم من ذلك تحدث إنهيارات كبيرة في أسواق البورصة بين فترة وآخرى وخير مثال على ذلك ما أ
... Show MoreThe auditor plays a key role in economic life because of the confidence his report adds to the audited financial statements. In applying the various stages of the audit process, the auditor must maintain a high moral level that determines his type of commitment in his professional behavior before God first, And to the society at last in a way that supports its independence. On this basis, the aim of the research is to identify the threats that affect the independence of the auditor. To achieve the objective of the research, the hypothesis that there is a statistically significant relationship between the threats facing the auditor and his professional independence was formulated. In the light of testing the hypotheses of research it was
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