Preferred Language
Articles
/
alkej-333
Active Vibration Suppression of Smart Cantilever Beam with Sliding Mode Observer Using Two Piezoelectric Patches
...Show More Authors

This paper presents a vibration suppression control design of cantilever beam using two piezoelectric ‎patches. One patch was used as ‎an actuator element, while the other was used as a sensor. The controller design was designed via the balance realization reduction method to elect the reduced order model that is most controllable and observable. ‎the sliding mode observer was designed to estimate six states from the reduced order model but three states are only used in the control law. Estimating a number of states larger than that used is in order to increase the estimation accuracy. Moreover, the state ‎estimation error is proved bounded. An ‎optimal LQR controller is designed then using the ‎estimated states with the sliding mode observer, to ‎suppress the vibration of a smart cantilever ‎beam via the piezoelectric elements. The control spillover problem was avoided, by deriving an avoidance ‎condition, to ensure the ‎asymptotic stability for the proposed vibration ‎control design. ‎The numerical simulations were achieved to ‎test the vibration attenuation ability of the ‎proposed optimal control. For 15 mm initial tip ‎displacement, the piezoelectric actuator found ‎able to reduce the tip displacement to about 0.1 ‎mm after 4s, while it was 1.5 mm in the ‎open loop case.  The current experimental results showed a good performance of the proposed LQR control law and the sliding mode observer, as well a good agreement with theoretical results.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed May 14 2025
Journal Name
Sciences Journal Of Physical Education
تأثير تمرينات خاصة باستخدام أساليب التنافس في تعلم مستوى األداء الفني لفعالية الوثب العالي للطالبات
...Show More Authors

فعالية الوثب العالي تمتاز بالتكرار والممارسة لمراحل التسلسل الحركي بالتكرارات الصحيحة المصحوبة بالتغذية الراجعة من اجل الوصول إلى اداء افضل, ومن خلال عمل الباحثتان كونها تدريسية لمادة الساحة والميدان لاحظت ضعفا في مستوى الأداء الفني عند الطالبات في ضبط مراحل التسلسل الحركي الكامل لفعالية الوثب العالي ، لذا ارتأت الباحثتان اعداد تمرينات خاصة باستخدام أساليب التنافس حمل المتعلم على مضاعفة جهده لينافس ذاته

... Show More
View Publication
Publication Date
Wed Apr 05 2023
Journal Name
Journal Of Engineering
Performance Evaluation of Small Scale Air-Conditioning System Using R22 and Alternative Refrigerants
...Show More Authors

A mathematical model has been formulated to predict the influence of high outdoor air temperature on the performance of small scale air - conditioning system using R22 and alternative refrigerants R290, R407C, R410A. All refrigerants were investigated in the cooling mode operation. The mathematical model results have been validated with experimental data extracted from split type air conditioner of 2 TR capacity. This entailed the construction of an experimental test rig which consists of four main parts. They are, the refrigeration system, psychrometric test facility, measuring instrumentation, and auxiliary systems. The conditioned air was maintained at 25 0C dry bulb and 19 0C wet bulb for all tests. The outdoor ambient air temperatur

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Thu Feb 13 2020
Journal Name
International Journal Of Environmental Research
Synthesis of a Novel Composite Sorbent Coated with Siderite Nanoparticles and its Application for Remediation of Water Contaminated with Congo Red Dye
...Show More Authors
Abstract

Re-use of the byproduct wastes resulting from different municipal and industrial activities in the reclamation of contaminated water is real application for green projects and sustainability concepts. In this direction, the synthesis of composite sorbent from the mixing of waterworks and sewage sludge coated with new nanoparticles named “siderite” (WSSS) is the novelty of this study. These particles can be precipitated from the iron(II) nitrate using waterworks sludge as alkaline agent and source of carbonate. Characterization tests using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) mapping revealed that the coating process was c

... Show More
Scopus (46)
Crossref (39)
Scopus Clarivate Crossref
Publication Date
Mon Sep 16 2024
Journal Name
Journal Of Optics
Improvement Of The Efficiency Of Optical Sensors Of Polypyrrole Using Graphene Oxide
...Show More Authors

This research explores the preparation of polypyrrole (PPy) using chemical oxidation and its enhancement with graphene oxide (GO) for optical sensor applications. PPy was synthesized by polymerizing pyrrole monomers with ferric chloride (Fe2Cl3) as the oxidant. The resulting PPy was then combined with GO to form a composite material, aiming to improve its electrical and optical properties. Polypyrrole nanofibers were obtained and after adding graphene oxide, the sensitivity increased. Characterization techniques including UV-Vis spectroscopy, DC conductivity measurements, Field Emission Scanning Electron Microscopy (FESEM) and response of photocurrent analysis were employed. The incorporation of GO into PPy resulted in a significant reducti

... Show More
View Publication
Scopus Clarivate Crossref
Publication Date
Tue Jun 01 2021
Journal Name
Journal Of The College Of Languages (jcl)
The passive of verbs constructed with prepositions: Das Passiv der mit Präpositionen konstruierten Verben
...Show More Authors

 Verbs in German and Arabic are of two types: active and passive. Passive voice  is a grammatical voice construction that is found in many languages.  Out of grammatical perspective, each main verb has a form in the active and one in the passive known as a "genus verbi" (type of verb). In passive voice, both in German and in Arabic, the focus is on the action itself or on the result of the action; often the perpetrator is not mentioned. In German, to conjugate verbs in the passive voice, you must know the forms of werden (to become). German uses werden  + the past participle and states it at the end of a sentence. In Arabic,

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Sep 01 2014
Journal Name
Al-khwarizmi Engineering Journal
Production of Bioethanol from Waste Potatoes
...Show More Authors

In this research, production of ethanol from waste potatoes fermentation was studied using Saccharmyses cerevisiae. Potato Flour was prepared from potato tubers after cooking and drying at 85°C. Homogenous slurry of potato flour was prepared in water at solid liquid ratio 1:10. Liquefaction of potato flour slurry with α-amylase at 80°C for 40 min followed by saccharification with glucoamylase at 65°C for 2 hr .Fermentation of hydrolysate with Saccharomyces cerevisiae at 35°C for two days resulted in production of 33 g/l ethanol.

      The parameters studied were; temperature, time of fermentation and pH. It was found that Saccharification process is affected by enzyme Amylo 300 conc

... Show More
View Publication Preview PDF
Publication Date
Wed Oct 31 2018
Journal Name
Arab Science Heritage Journal
من التراث من التراث البغدادي ...رياضة الزورخانة دراسة تاريخية
...Show More Authors

مارس العراقيون ومنهم سكان مدينة بغداد أنواعاً متعددة من الألعاب الرياضية الفردية منها السباحة ، الفروسية ، الساس ، الطابك ، والمصارعة بطريقتها القديمة ـ الزورخانة ـ وما تحملهُ من عادات وتقاليد وطقوس شبه دينية إضافة لما في حركتها من معاني القوة والبطولة ونجد أنَّ الذين يقبلون على مزاولتها عند انتشار بيوتاتها في بغداد فيما بعد هم من علية القوم ووجهاء مدينة بغداد ومن الذين كانوا يتمتعون بالاخلاق الدينية الفا

... Show More
View Publication Preview PDF
Publication Date
Thu May 01 2025
Journal Name
Journal Of Engineering
Transient Response Investigation of Cross-Ply Plates Using Refined Theory
...Show More Authors

Response of cross-ply plates subjected to transient load is obtained using five variables refined plate theory, and four variables plate theory. Equations of motion are derived through the principleof virtual work. Navier series used for simply supported laminated plates. The results of this work are presented for different parameters, such as the ply number, thickness, and modulus ratio with mechanical load (sinusoidal and step pulses), which are compared with those obtained using high-order shear plate theory. Five variables of refined plate theory give results that are considerably different from the four variables of refined plate theory and higher-order theory. The obtained results from the four variables theory have the same behavior

... Show More
Publication Date
Mon Apr 07 2025
Journal Name
Al-nahrain Journal For Engineering Sciences
Design of Reverse Osmosis Water Treatment Unit Using Lanxess Lewaplus2
...Show More Authors

Basrah is the richest town and the economic capital of Iraq. It suffers from lack of drinking water. This project is a dream to supply drinking water to Basrah citizens within WHO standards. Water should pass sedimentation and filtration stages before interring reverse osmosis unit. The design is carried out using lewaplus2 software. Several parameters should be selected in the design step membrane type, number of stages, number per element in each stage, and the recovery percentage. An optimization is carried out using Minitab ver. 18 for the acceptable limit of TDS and minimum cost and it was found that the optimum conditions were 52% for first stage, the numbers of vessels are 20 for both the first and second stage. In addition,

... Show More
View Publication
Scopus Crossref
Publication Date
Fri Aug 23 2013
Journal Name
International Journal Of Computer Applications
Lossless Compression of Medical Images using Multiresolution Polynomial Approximation Model
...Show More Authors

In this paper, a simple fast lossless image compression method is introduced for compressing medical images, it is based on integrates multiresolution coding along with polynomial approximation of linear based to decompose image signal followed by efficient coding. The test results indicate that the suggested method can lead to promising performance due to flexibility in overcoming the limitations or restrictions of the model order length and extra overhead information required compared to traditional predictive coding techniques.

View Publication
Crossref (4)
Crossref