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.
This paper presents a new approach to discover the effect of depth water for underwater visible light communications (UVLC). The quality of the optical link was investigated with varying water depth under coastal water types. The performance of the UVLC with multiple input–multiple output (MIMO) techniques was examined in terms of bit error rate (BER) and data rate. The theoretical result explains that there is a good performance for UVLC system under coastal water.
Sustainable development (SD) is an improvement that meets present needs but jeopardizes the ability of new populations to do the same. It is vital to acquaint EFL students with the terminology and idiomatic expressions of this discipline. Nowadays, sustainable development and the environment have been prioritized in every aspect of life. Since culture and the teaching of Foreign language English cannot be separated, the English language becomes the mean of communication in health, economics, education, and politics. Thus, integrating sustainable development goals within language learning and teaching is very important. This descriptive quantitative study aims to investigate the perception of EFL pre-service teachers of sustainable develo
... Show MoreAlopecia (Baldness) is very usual trouble in current time. It is accompanied by an intensive weakening of the scalp's hair and follows a specific pattern. Hereditary predisposition plays a very important role in alopecia despite not completely understood. Alopecia can be typed to various categories according to etiology, may be due to hereditary factors, autoimmune disease, and drugs or chemicals. There are many options of strategies of treatment according to the type and causes of alopecia. Chemical or synthetic medications apply for the management of hair loss are accompanied by a wide range of undesirable effects. Naturally occurring drugs also play important role in alopecia management with minimal side effects.
Al-Manas and Al-Muhais are two words in a close sense of the strange words of the Holy Quran. The word Al-Manas was mentioned once in the Holy Qur'an in Surat (PBUH). ) / 36 .. What we will see in the folds of the search, God willing.
Each Arab Islamic city is distinguished by its distinctive characteristics dictated by the nature of its location and its characteristics, as we see it mountainous in the mountains, deserts in the deserts, and coastal in the coasts, and this is reflected in the models of its buildings and designs and even in its structure. However, this uniqueness did not stand in the way of the emergence of characteristics and common characteristics of these cities over time, the factors derived from the core of the life of the community habits and traditions and beliefs and living requirements and environmental conditions that all piled in the process of building and construction of the Arab Islamic city to draw The features and lines of life of the co
... Show MoreIn the present work, experimental tests was done to explain the effect of insulation and water level on the yield output. Linear basin, single slope solar still used to do this purpose. The test was done from May to August 2017 in Mosul City-Iraq (Latitude: Longitude: Elevation: 200 m, and South-East face). Experimental results showed that the yield output of the still increased by 20.785% and 19.864% in case of using thermal insulation at 4cm and 5cm respectively, also the yield output decrease by 15.134% as the water level increase from 4 to 5cm, with the presence of insulation and 14.147% without it. It has been conclude that the insulation and water level play important role in the process of passive
... Show MoreAlthough severe epistaxis is uncommon, it is serious. The systematic endoscopic nasal examination is an essential step in identifying the bleeding point and aiding electrocauterization. Currently, the S-point, which is located in the superior part of the nasal septum behind the septal body and corresponding to the axilla of the middle concha, is identified in about 30% of cases with severe epistaxis. Cauterization of this point has an excellent rate of controlling the bleeding and preventing its recurrence. We aimed to highlight the significance of the S-point in the management of severe cases of epistaxis.
Moisture induced damage can cause a progressive deterioration in the performance of asphalt pavement by the loss of adhesion between asphalt binder and aggregate surface and/or loss of cohesion within the binder in the presence of water. The objective of this paper is to improve the asphalt mixtures resistance to moisture by using hydrated lime as an anti-stripping additive. For this purpose, two types of asphalt binder were utilized; asphalt grades (40-50) and (60-70) with one type of aggregate of 19.0 mm aggregate nominal maximum size, and limestone dust as a mineral filler. Marshall method was adopted to find the optimum asphalt content. Essentially, two parameters were determined to evaluate the moisture susceptibili
... Show MoreIntroduction The pathophysiology of appendicitis likely stems from obstruction of the appendiceal orifice leading to an increase in intraluminal and intramural pressure, resulting in small vessel occlusion and lymphatic stasis. Organ supplied by an end artery, such as the appendix, are more prone to the deleterious effects of arterial occlusion. The continuous cigarette smoking might be associated with a greater risk for developing atherosclerosis.
Objectives The aim is to evaluate the effect of cigarette smoking on the incidence of complications of acute appendicitis.
Methods Patients suffered from symptoms and signs suggesting a