أثبتت الشبكات المحددة بالبرمجيات (SDN) تفوقها في معالجة مشاكل الشبكة العادية مثل قابلية التوسع وخفة الحركة والأمن. تأتي هذه الميزة من SDN بسبب فصل مستوى التحكم عن مستوى البيانات. على الرغم من وجود العديد من الأوراق والدراسات التي تركز على إدارة SDN، والرصد، والتحكم، وتحسين QoS، إلا أن القليل منها يركز على تقديم ما يستخدمونه لتوليد حركة المرور وقياس أداء الشبكة. كما أن المؤلفات تفتقر إلى مقارنات بين الأدوات والأساليب المستخدمة في هذا السياق. تقدم هذه الورقة كيفية محاكاة إحصاءات المرور وتوليدها والحصول عليها من بيئة SDN. وبالإضافة إلى ذلك، تعالج المقارنة بين الأساليب المستخدمة في جمع بيانات شبكة المعرفة برمجياً لاستكشاف قدرة كل طريقة، وبالتالي تحديد البيئة المناسبة لكل طريقة. تمت محاكاة اختبار SDN باستخدام برنامج Mininet مع طوبولوجيا الأشجار ومفاتيح OpenFlow. تم توصيل وحدة تحكم RYU بإرسال التحكم. تُستخدم الأدوات الشهيرة iperf3 و ping و python scripts لجمع مجموعات بيانات الشبكة من عدة أجهزة في الشبكة. تم استخدام Wireshark وتطبيقات RYU وأمر ovs-ofctl لمراقبة مجموعة البيانات المجمعة. تظهر النتائج نجاحًا في إنشاء عدة أنواع من مقاييس الشبكة لاستخدامها في المستقبل لتدريب الآلة أو خوارزميات التعلم العميق. وخلصت إلى أنه عند توليد البيانات لغرض التحكم في الازدحام، فإن iperf3 هو أفضل أداة، في حين أن ping مفيد عند توليد البيانات لغرض الكشف عن هجمات DDoS. تعد تطبيقات RYU أكثر ملاءمة للاستفسار عن جميع تفاصيل طوبولوجيا الشبكة نظرًا لقدرتها على عرض الطوبولوجيا وخصائص التبديل وإحصائيات التبديل. كما تم استكشاف العديد من العقبات والأخطاء وإدراجها ليتم منعها عندما يحاول الباحثون إنشاء مجموعات البيانات هذه في جهودهم العلمية التالية.
BSTRACT: BACKGROUND: Acne vulgaris(AV)is chronic inflammatory disease of pilosebaceous unit of young people. Patients with acne with or with out scarring might differ in regard to their immunological background from those free from acne. OBJECTIVES: To evaluate the problem of facial AV especially patients with scarring and to determine the frequency of associated skin diseases and to be compared with acne free control. METHODS: A cross sectional randomized controlled epidemiological study was conducted from Oct.2005-Oct. 2006.Three hundred students from Basra University; 132 (44%) males and 168 (56%) females were enrolled, their ages ranged from 18-25 (20.9±1.8) years. They were divided into: Group A those free from acne (98 individuals),G
... Show MoreS Khalifa E, AH Khalil I, N Adil A, AB Razan A…, 2009
In this research a study of the effect of quality, sequential and directional layers for three types of fibers are:(Kevlar fibers-49 woven roving and E- glass fiber woven roving and random) on the fatigue property using epoxy as matrix. The test specimens were prepared by hand lay-up method the epoxy resin used as a matrix type (Quick mast 105) in prepared material composit . Sinusoidal wave which is formed of variable stress amplitudes at 15 Hz cycles was employed in the fatigue test ( 10 mm )and (15mm) value 0f deflection arrival to numbers of cycle failure limit, by rotary bending method by ( S-N) curves this curves has been determined ( life , limit and fa
... Show MoreOro slippery tablets (OSTs) is a technique used to improve swallowing of tablets for patients with dysphagia. The aim of this study was to formulate irbesartan and hydrochlorothiazide as Oroslippery tablets (OST) containing 150 mg irbesartan and 25 mg hydrochlorothiazide for dysphagia patients. A simple and rapid method of analysis was developed and validated according to the ICH guideline using HPLC with UV detector. Tablets were prepared by direct compression and then coated with the slippery coat of three different concentrations of the slippering substance “xanthan gum’ (2%, 3% and 4%) in Opadry Colorcone® and evaluated according to USP. Slipperiness test was performed using Albino rabbits. Results showed that 2% xanthan gum gav
... Show MoreIn this research, experimental and numerical studies were carried out to investigate the performance of encased glass-fiber-reinforced polymer (GFRP) beams under fire. The test specimens were divided into two peer groups to be tested under the effect of ambient and elevated temperatures. The first group was statically tested to investigate the monotonic behavior of the specimens. The second group was exposed to fire loading first and then statically tested to explore the residual behavior of the burned specimens. Adding shear connectors and web stiffeners to the GFRP beam was the main parameter in this investigation. Moreover, service loads were applied to the tested beams during the fire. Utilizing shear connectors, web stiffeners,
... Show MoreABSTRACT. The reaction between benzil and hexamethylenediamine formed a new ligand [L], [(1Z,3Z)-2,3-diphenyl-5,6,7,8,9,10-hexahydro-1,4-diazecine], of the type [N2], was synthesized by the condensation reaction through Schiff base reaction between benzil and hexamethylenediamine. The new Schiff base ligand reacts with Mnп, Niп and Coп metal ions to give the complexes with the general formula: [M(L)Cl2]. The elemental investigations have been used to analyze the ligand and its complexes by CHN, FT-IR, UV-Vis, TLC, mass spectrum, melting point with the study of biological activity to the formed compounds. From the data obtained, the proposed molecular structure adopts square planar structure about the metal ions. The study reveals
... Show MoreTo detect the amount of rifampicin in bulk and medicinal dosage formulations, an accurate and costeffective UV spectrophotometric technique has been developed using the area under the peak to estimate the presence of rifampicin. This range of wavelengths (300–356 nm) was chosen. The method showed linearity in the 2–22 μg/mL range, with R2 being2 0.9996. The developed method’s linearity, detection limit, quantification limit, precision, repeatability, and accuracy were all statistically and experimentally validated. The suggested methodology can be used for routine quality control analysis of rifampicin in pure form and in capsule dosage form, as demonstrated by the satisfactory recovery percentage results. This study explores the str
... Show MoreBackground: Dental implant considers a unique treatment option for the replacement of missing dentition. The new trend of implants is looking for materials which accelerate bone formation in bone implant interface and enhance osseointegration to provide immediate loading directly after placement and decrease the time period which is disturbs patients and uncomfortable. The aim of the study was to evaluate the effect of nano zirconium oxide (ZrO2) and nano hydroxyapatite (Hap) mixture coating of screw shaped commercially pure titanium (cpTi) implants on bond strength at the bone implant interface with torque removal test and histological analysis in comparison with non coated implants. Materials and methods: Forty screws were machined from c
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