This paper presents L1-adaptive controller for controlling uncertain parameters and time-varying unknown parameters to control the position of a DC servomotor. For the purpose of comparison, the effectiveness of L1-adaptive controller for position control of studied servomotor has been examined and compared with another adaptive controller; Model Reference Adaptive Controller (MRAC). Robustness of both L1-adaptive controller and model reference adaptive controller to different input reference signals and different structures of uncertainty were studied. Three different types of input signals are taken into account; ramp, step and sinusoidal. The L1-adaptive controller ensured uniformly bounded transient and asymptotic tracking for both system's input and output signals, simultaneously with asymptotic tracking. Simulations of a DC servomotor with time-varying friction and disturbance are presented to verify the theoretical findings.
The study (Quality in the Industrial Products Designs and its Reflection on Achieving Competitive Advantage) focused on developing the products in a way that satisfies human desires through the impact of technology on products design systems and performance enhancement. The study question is: how to effectively achieve quality in industrial products designs that influences competitiveness? The aim of the research is to show the design contexts for the product and its reflection on competitiveness. The study is limited to (LG) products in 2017-2018. The results and conclusions reached at by the researcher are included in the study.
The sample models adopted contexts, forms and relational relations transcending traditional contex
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The paper studies the science of “Biomimicry” or imitation of nature, and how to utilize it to create contemporary designs. It starts by defining biomimicry and innovation. Then, the style of imitating nature is highlighted, which is considered one of the most important methods of innovation. It includes simulating animals and plants (in their environmental conditions) to use the natural and dynamic design solutions to produce innovative designs, that enhance the concept of sustainability. Various forms of natural species are presented, to show their benefit in contemporary metal product designs. Finally, a model of a metal lighting unit is developed, where innovative ideas inspired by silkworm cocoon are used in its design. The stud
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Diverting river flow during construction of a main dam involves the construction of cofferdams, and tunnels, channels or other temporary passages. Diversion channels are commonly used in wide valleys where the high flow makes tunnels or culverts uneconomic. The diversion works must form part of the overall project design since it will have a major impact on its cost, as well as on the design, construction program and overall cost of the permanent works. Construction costs contain of excavation, lining of the channel, and construction of upstream and downstream cofferdams. The optimization model was applied to obtain optimalchannel cross section, height of upstream cofferdam, and height of downstream cofferdamwith minimum construction cost
... Show MoreThe water supply network inside the building is of high importance due to direct contact with the user that must be optimally designed to meet the water needs of users. This work aims to review previous research and scientific theories that deal with the design of water networks inside buildings, from calculating the amount of consumption and the optimal distribution of the network, as well as ways to rationalize the use of water by the consumer. The process of pumping domestic water starts from water treatment plants to be fed to the public distribution networks, then reaching a distribution network inside the building till it is provided to the user. The design of the water supply network inside the building is
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Background: Dental implant surface technologies have been evolving rapidly to enhance a more rapid bone formation on their surface and improve implant therapy.Implant threads should be designed to increase surface contact areathat induced better stability. In addition, implant surface coating with Flaxseed was used to enhance bone formation at the bone-implant interface. Materials and methods: Ninety-six commercially pure titanium (CpTi) screws were implanted in rabbits' tibiae and divided into three groups as dual-threaded group, flaxseed-coated group and control group. All groups were evaluated mechanically, histologically and radiographically after each healing periods (2, 4, 6 and 8) weeks and the resulting data were statistically analy
... Show Moreتركز هذا البحث على تصميم عدسة كهروستاتيكية ثلاثية الاقطاب اسطوانية الشكل متحدة المركز ومفصولة بفتحة هوائية . تم حل معادلة لابلاس بطريقة كثافة الشحنة في مجال بصريات الجسيمات المشحونة اللانسبية وبغياب تأثيرات شحنة الفضاء إن توزيع الجهد المحوري لعدسة ثلاثية كهروستاتيكية تم حسابه باستخدام كثافة الشحنة الموزعة على الاقطاب، الناتجة من تسليط فولتية معينة على الاقطاب اعتمادا على ق
... Show Moreان تقدير مسؤولية المحاسب في تصميم نظام المعلومات المحاسبي من منظور تاريخي سبقت استخدام الحاسوب كأداة معلوماتية للاعمال، لما له من رؤيا بالتطورات الرئيسية لنظام المعلومات والتي اهمها تحديد متطلبات مستخدمي المعلومات وتعيين مضمون وشكل مخرجات النظام من التقارير وتحديد مصادر البيانات وانتقاء القواعد المحاسبية الملائمة فضلاً عن الرقابة الضرورية لتكامل وفاعلية النظام.
ان النظم المحاسبية التقليدية غالبا
... Show MoreDeveloped technologies and complementary means for viewing theater through the ages, and they affected would improve and get better. Valsinogravea appeared to express a description and identification of existing in the theatrical space of lighting and decorative structure architecture, and the lighting of the elements that have contributed since ancient times in the process of the show, and played a significant role in strengthening the relationship between the recipient and actor and presentation theater as a whole scenes, working to broadcast a dramatic speech theatrical holds ideas and content and symbols and semantics affect the spectator of different age, particularly the child viewer, that little spectator who represent the
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