Abstract: Recently, there is increasing interest in using mode-division multipelexing (MDM) technique to enhace data rate transmission over multimode fibers. In this technique, each fiber mode is treated as a separate optical carrier to transfer its own data. This paper presents a broadband, compact, and low loss three-mode (de)multiplexer designed for C+L band using subwavelength grating (SWG) technology and built-in silicon-on-insulator SOI platform. SWG offers refractive index engineering for wider operating bandwidth and compact devices compared to conventional ones. The designed (de)multiplex deals with three modes (TE0, TE1, and TE2) and has a loss > -1 dB and crosstalk < −15 dB, and its operation cover 160 nm (1490 to 1650) nm wavelength span. The overall size of the designed device is 80 × 4 μm2.
قبل سنوات عدة أصدرت وزارة التعليم العالي والبحث العلمي تعليمات بتدريس مادة اللغة العربية في الجامعات اهتماما منها باللغة العربية وضرورة الحفاظ عليها فضلا عن سعيها لوضع الأسس الراسخة للغة بغض النظر عن تخصص الدارسين وفي جميع الاختصاصات.
لقد لوحظ من خلال تدريس مادة اللغة العربية للصف الأول من الجامعات ضعف اهتمام الطلبة بالمادة والنظر إليها على أنها مادة ثانو
... Show Moreمشكلة البحث واهميته :-
تنبع مشكلة البحث الحالي من الآثار الاجتماعية سواء أكان على مستوى الفرد أم المجتمع . أذ العزوف عن الزواج مشكلة اجتماعية بل انها مشكلة حقيقية , فهناك عزوف من الشباب عن الزواج وقد اصبح العدد كبيرا في السنوات الأخيرة وقد بينت إحصائية متخصصة بأن عدد العازفين عن الزواج يقدر بأكثر من مليون شاب وشابة (2-2ص3) . وهذا يعود لأسباب عديدة فقد يكون العامل الاقتصاد
... Show MoreThe goal (purpose) from using development technology that require mathematical procedure related with high Quality & sufficiency of solving complex problem called Dynamic Programming with in recursive method (forward & backward) through finding series of associated decisions for reliability function of Pareto distribution estimator by using two approach Maximum likelihood & moment .to conclude optimal policy
Economic performance is one of the most important indicators of economic activity and with the performance of the economy progress varied sources of output and increase economic growth rates and per capita national income, and to recover the business environment and increase investment rates and rising effectiveness of the financial and monetary institutions and credit market. Which leads to increased employment rates and reducing unemployment rates and the elimination of many of the social problems and improve the average per capita income as well as improve the level of national income.
The input / output tables is a technique mathematical indicates economic performance
... Show MoreAbstract. In this paper, a high order extended state observer (HOESO) based a sliding mode control (SMC) is proposed for a flexible joint robot (FJR) system in the presence of time varying external disturbance. A composite controller is integrated the merits of both HOESO and SMC to enhance the tracking performance of FJR system under the time varying and fast lumped disturbance. First, the HOESO estimator is constructed based on only one measured state to precisely estimate unknown system states and lumped disturbance with its high order derivatives in the FJR system. Second, the SMC scheme is designed based on such accurate estimations to govern the nominal FJR system by well compensating the estimation errors in the states and the lumped
... Show MoreIn this work, the possibility of a multiwavelength mode-locked fiber laser generation based on Four-Wave Mixing (FWM) induced by Fe2O3-SiO2 nanocomposite material is investigated for the first time. A multiwavelength mode-locked pulses fiber laser are generated from Ytterbium–doped fiber laser (YDFL) due to the combined action of high nonlinear absorption and high refractive coefficients of Fe2O3-SiO2 nanocomposite incorporated inside YDFL ring cavity. Up to more than 20 lasing lines in the 1040–1070 nm band with an equally lines separation of ~0.6 nm have been observed by just simple variation of passive modulation of the state of the polarization and the pump power altogether. Moreover, a passively mode-locked operation of YDFL laser
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