This paper investigates the performance evaluation of two state feedback controllers, Pole Placement (PP) and Linear Quadratic Regulator (LQR). The two controllers are designed for a Mass-Spring-Damper (MSD) system found in numerous applications to stabilize the MSD system performance and minimize the position tracking error of the system output. The state space model of the MSD system is first developed. Then, two meta-heuristic optimizations, Simulated Annealing (SA) optimization and Ant Colony (AC) optimization are utilized to optimize feedback gains matrix K of the PP and the weighting matrices Q and R of the LQR to make the MSD system reach stabilization and reduce the oscillation of the response. The Matlab software has been used for simulations and performance analysis. The results show the superiority of the state feedback based on the LQR controller in improving the system stability, reducing settling time, and reducing maximum overshoot. Furthermore, AC optimization shows significant advantages for optimizing the parameters of PP and LQR and reducing the fitness value in comparison with SA optimization
The purpose of this study was to develop poloxamer-based in-situ gel of chloramphenicol aiming to increase bioavailability and prolong corneal contact time, controlling drug release, and enhancing ocular bioavailability. The in-situ gel was prepared using different concentrations of poloxamer 407 combined with hydroxypropyl methyl cellulose (HPMC) or carbapol 940 to achieve gelation temperature about physiological temperature and improve rheological behavior and gelling properties of poloxamer gel. The prepared formulations were evaluated for their appearance, pH, and sol-gel transition temperature. The formulations F2, F3, and F5 have a gelation temperature within the accepted range 35-370C an
... Show MoreSilymarin (SM) is a plant extract obtained from Silybum marianum( milk thistle) . It is class II type drug according to Biopharmaceutics Classification System with low bioavailability due to its low solubility.
Micro/nanonization during crystallization, surface modification and crystal structure modification may improve the dissolution rate of poorly water-soluble drugs.
The aim of this study was to increase the water solubility and dissolution rate of SM by in-situ micronization using solvent change either by stirring or ultrasonic method. Stabilizers like Gelatin, PVP-K30, HPMC15, Pulullan were used to stabilize the prepared ultrafine crystals. Effect of type and concentration of hydrophilic polymer, solv
... Show MoreBackground: Bilastine is a non-sedating, second-generation antihistamine used to treat urticaria and allergic conjunctivitis. Objective: to formulate and test bilastine as a mucoadhesive ophthalmic in situ gel in order to extend its presence at site for longer time and help treat conjunctivitis and allergic rhinitis. Methods: We prepared formulations using different concentrations of poloxamers (Poloxamer 407 (P407) and Poloxamer 188 (P188)) in combination with hydroxypropyl methyl cellulose (HPMC). The prepared formulas were evaluated for their physicochemical properties, sol-gel transition temperature, viscosity, mucoadhesive strength, drug release, and kinetic modeling. Results: The prepared in situ gels were clear and transparen
... Show MoreTechnically, mobile P2P network system architecture can consider as a distributed architecture system (like a community), where the nodes or users can share all or some of their own software and hardware resources such as (applications store, processing time, storage, network bandwidth) with the other nodes (users) through Internet, and these resources can be accessible directly by the nodes in that system without the need of a central coordination node. The main structure of our proposed network architecture is that all the nodes are symmetric in their functions. In this work, the security issues of mobile P2P network system architecture such as (web threats, attacks and encryption) will be discussed deeply and then we prop
... Show MoreFive species of Lactic acid bacteriawere isolated from raw milk, yoghurt, vegetables and pickles, Lactobacillus plantarum, Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus casei and Lactobacillus bulgaricus isolates were identified by 16S rRNA gene. Evaluate of antimicrobial activity against all the bacterial strains Staphylococcus aureus, Salmonella spp., Pseudomonas fluorescens, Escherichia coli, Bacillus cereus and Bacillus subtilis. It showed that bacteriocin of Lactic acid bacteriamore effective than supernatant of lactic acid bacteria, the results showed that isolatemost efficient isolate belonging to Lactobacillus brevis, the diameter of the inhibition of the bacteriocin of Lactobacillus brevis were 27.7, 26.3 and 25.1
... Show MoreDarifenacin hydrobromide (DH) is the more recent uroselective M3 receptor antagonist for treating uncomplicated overactive bladder (OAB). This study was aimed to formulate DH as fast dissolving buccal films (FDBFs) using a solvent casting method to enhance patient’s compliance.
Films were prepared by using polyvinyl alcohol (PVA) as a film forming polymer. Different types and concentrations of superdisintegrants (croscarmellose sodium, sodium starch glycolate, indion 414) were used to select the best formula by studying the physicochemical properties of the films, disintegration time (DT) and percent drug release.
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... Show MoreBackground: Sliding mechanics is widely used during orthodontic treatment. One of the disadvantages of this mechanics is the friction generated at the bracket/archwire interface, which may reduce the amount of desired orthodontic movement obtained. The aim of the present in vitro study was to evaluate and compare the static frictional forces produced by two passive self-ligating brackets stainless-steel and hybrid and two conventional brackets stainless-steel and monocrystal ligated with stainless-steel ligature wire at two degrees of torque(zero and twenty) under dry condition. Materials and method: One hundred and sixty brackets were used in this study divided into four groups each group consisted of forty brackets these are: Two self-li
... Show More“Orodispersible Tablet†a tablet that is to be placed in oral cavity where it disperses rapidly by saliva with no need for water before swallowing. Zaltoprofen (ZLP) is one of NSAIDs which is used in the treatment of rheumatoid arthritis and osteoarthritis as well as to relieve inflammation and pain after surgery, injury and tooth extraction. The present study was aimed to prepare rapidly dissolved lyophilized Zaltoprofen tablet with different pharmaceutical excipients and studying the factors affecting pharmaceutical properties like (solubility, disintegration time DT, dissolution, etc.) of tablets. The lyophilized disintegrating tablets (LDTs) were prepared using Zydis technique by lyophilization an aqueous
... Show MoreThe current research aims to verify the relationship and impact of internal control activities as an independent variable in its dimensions (efficiency, training, independence) in making administrative decisions as a responsive variable and its dimensions (identifying and diagnosing the problem, searching for alternatives, evaluating alternatives, choosing the appropriate alternative, implementing the decision, following up Decision and evaluation) in the Kirkuk Water Directorate, as well as to identify the levels of their practices, and then try to come up with a number of recommendations contribute to the strengthening of internal control activities and the process of making administrative decisions of the researched Directorat
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