A compact microstrip six-port reflectometer (SPR) with extended bandwidth is proposed in this paper. The design is based on using 16-dB multi-section coupled line directional couplers and a multi-section 3-dB Wilkinson power divider operating from 1 to 6 GHz. The proposed SPR employs only two calibration standards: a matched load and an open load. As compared to other dielectric substrates, fabricating the proposed SPR involves using a low-cost (FR4) substrate. A novel algorithm is also proposed to estimate the complex reflection coefficient over the frequency ranges at which the standard performance of the circuit components is not fully satisfied. The new algorithm is based on the circles’ intersection points, which have been derived from basic SPR equations, to estimate the complex reflection coefficient. To validate the SPR performance, a multiband microstrip patch antenna has been measured and the resulted reflection coefficient is compared with those obtained using a vector network analyzer (VNA). Results show that the proposed SPR provides a good estimation of the complex reflection coefficient within the frequency range of 1 GHz to 8 GHz. Owing to its compact size and ease of fabrication, the proposed reflectometer is suitable for various microwave broadband applications.
The new compounds synthesized by sequence reactions starting from a reaction of 4-hydroxybenzaldehyde with 1,5-dibromo pentane to produce dialdehyde)I(
.Then compound )I( reacted with different aromatic amines to give schiff bases )II-IV(,thereafter added acetyl chloride to schiff bases to yield N-acyl derivatives)V-VII(.While1,3-diazetine derivatives)VIII-X( were synthesized from the reaction of N-acyl derivatives with sodium azide.The reaction of thiourea with N-acyl compounds led to formation of thiourea derivatives (XI-XIII).Finally, the pyrimidine compounds )XIV-XVI( were synthesized by ring closure reaction of compounds(XI-XIII) with diethyl malonate.The synthesized compounds were characterized by measurements of melting points,
At the beginning of the twentieth century distorting handling totalitarian phenomena of art, which can be called the stage of the test, transition from the theory of ideal theory and other realistic is not cushy, since it requires vision and reading and other concepts, and in light of this dialectic manifested research problem by asking the following Is affected by the design idealism and realism. Through the above mentioned questions, the researcher found rationale for addressing this problem, the study through his research, which is marked (idealism and realism in a comparative study design). And demonstrated the importance of research in the identification of the concept and the effectiveness of the two theories idealism and realism a
... Show MoreThis paper presents a cognition path planning with control algorithm design for a nonholonomic wheeled mobile robot based on Particle Swarm Optimization (PSO) algorithm. The aim of this work is to propose the circular roadmap (CRM) method to plan and generate optimal path with free navigation as well as to propose a nonlinear MIMO-PID-MENN controller in order to track the wheeled mobile robot on the reference path. The PSO is used to find an online tune the control parameters of the proposed controller to get the best torques actions for the wheeled mobile robot. The numerical simulation results based on the Matlab package show that the proposed structure has a precise and highly accurate distance of the generated refere
... Show MorePraise be to God, and may blessings and peace be upon the Messenger of God, his family and companions, and from his family and after ...
It is the right of every nation to be proud of its heritage, science and civilization among the nations, taking pride in the efforts of its construction and the keenness of its scholars and dedication to serve their nation and their history, and from the great sciences that boast and honor our great nation and distinguish it over others the science of attribution and the preservation of the novel over generations and ages. The novel is preserved from the plagiarism of the nullified, the excess of the deceitful and the liars, and the science of isnad from religion as the scholars said, and without the
The present investigation revealed cytological variations for six species (Eruca sativa, Sisymbirium irio, Diplotaxis harra, Erucaria hispanica, Schimpera Arabica and Brassica tournefortii ) belong to the Brassicaceaefamily.The flower buds were collected from Al-Habania lake that located in Al-Anbar-Iraq. Using iron-acetocarmine squash technique in anther-smear studies which revealed a chromosomal anomalies such as Lagging/brddge chromosomes, Micronuclei & initiated delay of four daughter cells.The frequency of abnormalities ranged (0.04 - 0.77%) which indicated the unstable heredity source of most wildplants. The pollen grains viability was estimated using acetocarmine stain, viable grains had stained, while sterile grains had not.T
... Show MoreThe present investigation revealed cytological variations for six species (Eruca
sativa, Sisymbirium irio, Diplotaxis harra, Erucaria hispanica, Schimpera Arabica
and Brassica tournefortii ) belong to the Brassicaceaefamily.The flower buds were
collected from Al-Habania lake that located in Al-Anbar-Iraq. Using ironacetocarmine
squash technique in anther-smear studies which revealed a
chromosomal anomalies such as Lagging/brddge chromosomes, Micronuclei &
initiated delay of four daughter cells.The frequency of abnormalities ranged (0.04 -
0.77%) which indicated the unstable heredity source of most wildplants. The pollen
grains viability was estimated using acetocarmine stain, viable grains had stained,while st
Many of accurate inertial guided missilc systems need to use more complex mathematical calculations and require a high speed processing to ensure the real-time opreation. This will give rise to the need of developing an effcint
Histone deacetylase inhibitors with zinc binding groups often exhibit drawbacks like non-selectivity or toxic effects. Thus, there are continuous efforts to modify the currently available inhibitors or to discover new derivatives to overcome these problems. One approach is to synthesize new compounds with novel zinc binding groups. The present study describes the utilization of acyl thiourea functionality, known to possess the ability to complex with metals, to be a novel zinc binding group incorporated into the designed histone deacetylase inhibitors. N-adipoyl monoanilide thiourea (4) and N-pimeloyl monoanilide thiourea (5) have been synthesized and characterized successfully. They showed inhibition of growth of human colon adenoc
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