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ANALYSIS AND SIMULATION OF THE TARGET-ATTACKER AND THE TARGET-ATTACKER-DEFENDER PROBLEMS
No full textA Thesis Submitted to the Faculty of Engineering at Cairo University in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE in Aerospace EngineeringThis thesis deals with two scenarios of target defense. We first present several methodologiestofindtheoptimalescapemaneuverforatargetagainstanattackingmissile. Wesimulate two-dimensional proportional-navigation using MATLAB and Simulink. Optimization is achieved via the techniques of Monte-Carlo simulation and genetic algorithms. We establish a Graphic User Interface (GUI) Guidance toolbox containing our guidance law and several typesofmaneuvers. Thistoolboxisanopen-sourceprogramforthedevelopmentandaddition of other guidance laws and maneuvers. We also construct a mathematically-correct game of target-attacker and let many people play it taking the target side. We find the best escape maneuver by collecting and analyzing data of the human escape maneuver. The game is developedusingUnity,afreereadily-availablecross-platformgameengine. Wethenconsider the case when the target is being helped by a defender. We offer a unified analytic treatment of this active defense problem via the construction of two Apollonius circles, considering all possibilities of the ratio between the speeds of the attacker and defender. A criticality condition is derived, from which we obtain the critical target speed and the Voronoi diagram borderingthesafeorescaperegionforthetargetoptimalstrategies. Ournumericalresultsand plotsallowusefulandinsightfulqualitativeinterpretations. Next,wefindtheoptimalheading angles to be followed by the target so as to stay in the safe region. We use Hamiltonian equations to formulate an exact two-point boundary value problem that is solved numerically, yielding results verifying our earlier results.Under the Supervision of
Prof. Ayman H. Kassem Prof. Gamal El-Bayoum
FLEXURAL STRENGTHENING OF REINFORCED CONCRETE GIRDERS USING POST-TENSIONED CONCRETE JACKETS
No full textThesis Submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE in CIVIL ENGINEERING (STRUCTURES)Flexural strengthening of reinforced concrete girders is an important side of the construction industry and its importance is on the rise. There are different techniques used to study the response of repaired and strengthened girders, each with different advantages and drawbacks. External pre-stressing was initially developed for retrofitting of bridges, but now it is used for both retrofitting and in building new structures. Due to its simplicity and cost effectiveness, pre-stressed concrete bridges with external pre-stressing are becoming popular.
This study discusses the flexural behavior of reinforced concrete girders strengthened using post-tensioning embedded in concrete jackets. The concept benefits from the external jacket to help increase the cross-section inertia as well as to host the posttensioning tendons without the need of external deviators. This study incorporated two phases namely, experimental and analytical phases. The experimental phase of this study was conducted on two stages. The first stage deals with girders loaded on their original section firstly and then strengthened with the posttensioned jacket and loaded to failure, while the second had the girders that were strengthened before being subjected to loads. In addition to the stage of jacket introduction, the difference between the original girder and the jacket’s concrete compressive strength was also studied. The experimental results showed that both the strength and the stiffness of the girders were enhanced significantly, this means that this technique can be used for mitigating the effect of increased deflections as well as loss of strength, the stage at which the jacket is introduced slightly affects the strength and stiffness of the girders. In the analytical phase of the study, a numerical model was built using the finite element method to simulate the response of the tested girders in the experimental phase. The analytical results show a very good match and correlation with the experimental results. A parametric study was developed on the flexural behavior of strengthen girders to investigate the effect of the damage level of girder before strengthening as well as increasing the pre-stressing ratio, also to study the effect of increasing the compressive strength of the original girder. The analytical results showed that, the stiffness and the strength of the strengthened girders increase with the decrease of the damage level for the original girder, and the load carrying capacity increases by increasing the percentage of pre-stressing area to the total cross-sectional area. Also, it was observed that the stiffness of the girders was enhanced significantly by increasing the concrete compressive strength of the original girderSupervised by Dr. Amr Abdelrahman ; Dr. Hussein Okai
Gingival Overgrowth: Drug-induced versus Hereditary and Idiopathic
No full textGingival overgrowth (GO) is the abnormal enlargement of maxillary and mandibular gingiva. It can be caused due to different etiological factors inherited (hereditary) gingival fibromatosis (HGF), accompanied with diseases characterizing syndrome; idiopathic gingival fibromatosis (IGF) or as a side effect of an adverse drug reaction (ADR) known as drug-induced gingival fibromatosis (DIGF). The hypertrophic gingiva is also accompanied with variable growth factors expression at cellular and molecular levels. It is well observed in fibroblasts activity and production of collagenous fibers in connective tissues as well as their degradation. Thus, it would be useful to identify and explore different factors related to gingival growth changes to help in treatment plans. This review article will throw the light on systemic, pathological, histological and immuniohistochemical aspects associated with both HGF and DIGF
التكالب الدولي على الصومال وچيبوتي وإريتريا وتأثيره على الأمن القومي المصري : ورقة مقدمة إلى ندوة "المصالح المصرية وتحولات المشهد الجيوستراتيچي في شرق أفريقيا" المركز القومي لدراسات الشرق الأوسط
No full textبعد مناقشات مكثفة حول المصالح القومية المصرية في شرق أفريقيا، وفي إطار التكالب الدولي على جيبوتي وإريتريا والصومال، وفي ضوء الخطوات الجادة في تعامل الدولة المصرية مع دول شرق ووسط أفريقيا؛ فإنه يمكن القيام بما يلي:
1- تعديل فكرة حلف الناتو العربي كما هو وارد في صفحة 11 لكي يضم دول شرق أفريقيا العربية وغير العربية ويكون موجهًا ضد دول الجوار، ومنها أثيوبيا.
2- إعادة توظيف القوى الناعمة المصرية، وعلى رأسها تبادل الطلاب وأساتذة الجامعات.
3- حتمية التفاوض بشأن الحصول على قاعدة بحرية -إن لم يكن قاعدة عسكرية متكاملة- في دولة من الدول الآتية (على الترتيب)؛ جيبوتي أو الصومال -وربما أرض الصومال- أو إريتريا.
4- التنسيق الاستراتيجي بين مصر والإمارات العربية المتحدة، وذلك التأكيد على احتمال استخدام مصر للقواعد العسكرية الإماراتية في جيبوتي، أو عصب.المصالح القومية المصرية في شرق أفريقيا، وفي إطار التكالب الدولي على جيبوتي وإريتريا والصومال، وفي ضوء الخطوات الجادة في تعامل الدولة المصرية مع دول شرق ووسط أفريقي
مشروع دار مصر العبور
No full textظهرت حاجة الإنسان إلي البناء منذ أن خلقه الله سبحانه وتعالي في الأرض وكلفه أن يستعمرها فكان بناء مسكن يأوي إليه الإنسان هو أول مشروع تشييد عرفه الإنسان وتطور البناء عبر العصور حتي أصبح لها مختصين يقومون بها ولمواكبة متطلبات الإنسان المتزايدة ظهرت الحاجة الي تشييد منشأت أخري غير المباني السكنية مثل الجسور والسدود والقناطر والتي كان يقوم ببنائها ايضا البناءو
Design of novel injectable in-situ forming scaffolds for non-surgical treatment of periapical lesions: In-vitro and in-vivo evaluation
No full textPeriapical lesions are considered one of the most famous painful teeth disorders. The primary
focus of this study was to investigate the effectiveness of formulating an injectable in-situ
forming scaffold-loaded with risedronate (bone resorption inhibitor) and with lornoxicam (antiinflammatory
drug) for the non-surgical treatment of periapical lesions. The scaffolds were
prepared using solvent-induced phase inversion technique. Two insoluble copolymers were
investigated namely; PLGA (ester-terminal) and PLGA-A (acid-terminal), additionally, SAIB
was added as a high viscosity water-insoluble carrier. The addition of porogenic agents like hydrolyzed collagen was also investigated. The prepared scaffolds were characterized by
analyzing their in-vitro release, DSC and rheological properties, besides their morphological
properties. The results showed that the scaffolds prepared using 30% (w/v) PLGA or combined
PLGA: SAIB (1:1, w/w) with total polymer concentration of 30% (w/v) possessed the most
sustained drug release profile. Selected scaffolds were tested for their therapeutic effect to study
the effect of porogenic agent, anti-inflammatory drug and risedronate in periapical lesions
induced in dogs' teeth. Results declared that the selected scaffolds succeeded in improving the
inflammation and enhancing the formation of new bony regions confirming the success of the
prepared scaffolds as an innovative approach in the treatment of bone defects
The anorectic agent, lorcaserin, disturbs estrous cyclicity and produces endometrial hyperplasia without affecting ovarian population in female rats
No full textLife Sciences
Volume 183, 15 August 2017, Pages 69-77Aims
The present study aims to investigate the effect of the new anorectic agent, lorcaserin, on estrous cyclicity, reproductive hormones and folliculogenesis in female mature rats.
Materials and methods
Rats were divided into four groups; Group i: control group. Group ii-iv: rats treated with lorcaserin (5, 10 or 30 mg/kg/day, p.o.), respectively. The treatment continued for 28 days.
Key findings
Lorcaserin (5 or 10 mg/kg) caused estrous cycle disturbance in 40% of treated rats while the high dose (30 mg/kg) produced disturbances in 100% of the treated rats. Lorcaserin (5–30 mg/kg) altered some of female hormones where it enhanced estradiol but reduced luteinizing hormone. Minimal edema with congested vessels was observed in the medulla of ovarian sections. Further, epithelial and uterine sections showed hyperplasia.
Significance
Taken together, the present results demonstrated that lorcaserin affected some reproductive hormones, disturbed estrous cyclicity and induced histopathological changes in the ovaries and uteri without affecting the ovarian populations. Therefore, lorcaserin should be used with caution in women of child bearing potential until adequate clinical safety data are available
Design and In Vitro/In Vivo Evaluation of Ultra-Thin Mucoadhesive Buccal Film Containing Fluticasone Propionate
No full textFluticasone propionate is a synthetic corticosteroid drug distinguished by its potent anti-inflammatory action with low systemic side effects in comparison to other corticosteroids making it a potential drug for local buccal delivery. The aim of the present study was to design mucoadhesive buccal film containing fluticasone that is aesthetically acceptable and could maintain local drug release for a sustained period to manage the sign and symptoms of severe erosive mouth lesions. Solvent casting technique was used in film preparation. Different polymeric blends were used either alone or in combination with mucoadhesive polymers, sodium carboxymethyl cellulose (SCMC), or Carbopol 971P at different concentrations. The physicochemical properties, in vitro mucoadhesion time as well as the drug release properties for all prepared formulations were determined. Selected formulations with adequate properties were further examined by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) and subjected to in vivo evaluation. Films containing hydroxypropyl methylcellulose (HPMC)/ethyl cellulose (EC) showed acceptable physicochemical properties, homogenous drug distribution, convenient mucoadhesion time, moderate swelling as well as sustained drug release up to 12 h. The biological performance of these formulations was assessed on healthy human volunteers and compared with a prepared mouthwash which showed enhanced pharmacokinetic parameters for the selected films in comparison to the mouthwash. The results revealed that the optimized formulation containing HPMC/EC and 10% SCMC could successfully achieve sustained drug release for 10 h which is considered promising for local treatment of severe mouth lesions
Impact of TV Terrorism News on Egyptians’ Perception of National Security Measures and Civil Liberties : A Cultivation Study
No full textThis study aims at examining the role of terrorism-related TV news content in cultivating terrorism risk perceptions among Egyptians in the aftermath of the June 30, 2013 events. The study also attempts to explore in-depth how and why terrorism threat perceptions correlate with the Egyptian people’s tolerance for more restrictive government measures regarding privacy and security. Previous studies found that heavy exposure to terrorism-related news can breed threat perception and fear of victimization. Further, citizens who feel under threat tend to be more willing to trade off their civil liberties. In this sense, the theoretical framework of this study is the Cultivation theory. The researcher employed the qualitative research method, involving twenty in-depth interviews conducted with expert and non-expert participants. According to the findings of this study, most of the research participants are light viewers who are affected by terrorism. The study also found that most research participants trust the official statements regarding the level of terrorism and the endorsed security-oriented measures. Based on this, participants expressed their willingness to compromise their civil liberties under the threat of terrorism
An Evaluation Framework for Business Process Modeling Techniques
No full textThere are numerous Business Process Modeling Techniques (BPMTs) that capture the Business
Process; each with different perspectives, capabilities, features and limitations. In addition, there is no one single Modeling Technique that’s suitable for all Business Processes in the organizations. Difficulties arise when the stockholders have to select the right Model for their Business Process. Moreover, selecting an unsuitable modeling technique will lead to some obstacles e.g. defect in describing the Process as a real world, increase the complexity, decrease the understandability and communication, consuming the time, and inefficient execution, all these obstacles lead to an inability to achieve
the expected goals. The main goal of this paper is to develop an evaluation framework for the Business Process Modeling Techniques, in order to help in selecting the most suitable Modeling Technique for each Business Process. The evaluation Framework has been developed based on two main phases; the first phase focuses on understanding and analyzing a specific Business Process needs, and the
second phase aims to match the Business Process needs with the characteristics of the BPMTs, in order to find the suitable Modeling Technique