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Challenges and limits of fractal and slot antennas for WLAN, LTE, ISM, and 5G communication: a review paper
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Abstract Portable communication devices such as WLAN, WiMAX, LTE, ISM, and 5G utilize one or more of the triple bands at (2.32.7 GHz,3.4–3.6GHz,and5–6GHz)andsufferfromtheeffectofmultipathproblemsbecausetheyareusedinurbanregions.To date, no one has performed a review of the antennas used for these types of wireless communications. This study reviewed two types of microstrip antennas (slot and fractal) that have been reported by researchers (as a single element) using a survey that included the evaluation of several important specifications of the antennas in previous research, such as operating bandwidth, gain, efficiency, axial ratio bandwidth (ARBW), and size. The weaknesses in the design of all antennas were carefully identified to determine the most important challenges in the design of these antennas and name the most important limits in the design to be overcome in future research. This study also indicated some antennas that have circular polarization characteristics, the techniques used to generate the circular polarization characteristics, and the challenges. Finally, several suggestions as a guideline for antenna design and future work in designing antennas for Wi-Fi, LTE, and WiMAX communications, according to the market demands, and methods for overcoming the identified limits are presented.

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Publication Date
Mon Nov 01 2021
Journal Name
Journal Of Engineering
Study of Using of Recycled Brick Waste (RBW) to produce Environmental Friendly Concrete: A Review
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Several million tons of solid waste are produced each year as a result of construction and demolition activities around the world, and brick waste is one of the most widely wastes. Recently, there has been growing number in studies that conducted on using of recycling brick waste (RBW) to produce environmentally friendly concrete. The use of brick waste (BW) as potential partial cement or aggregate replacement materials is summarized in this review where the performance is discussed in the form of the mechanical strength and properties that related to durability of  concrete. It was found that, because the pozzolanic activity of clay brick powder, it can be utilized as substitute for cement in replacement level up to 10%. Whereas,

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Publication Date
Sun Aug 01 2021
Journal Name
Journal Of Engineering
Utilization of Iraqi Metakaolin in Special Types of Concrete: A Review Based on National Researches
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Portland cement concrete is the most commonly used construction material in the world for decades. However, the searches in concrete technology are remaining growing to meet particular properties related to its strength, durability, and sustainability issue. Thus, several types of concrete have been developed to enhance concrete performance. Most of the modern concrete types have to contain supplementary cementitious materials (SCMs) as a partial replacement of cement. These materials are either by-products of waste such as fly ash, slag, rice husk ash, and silica fume or from a geological resource like natural pozzolans and metakaolin (MK). Ideally, the utilization of SCMs will enhance the concrete performance, minimize

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Publication Date
Thu Feb 01 2024
Journal Name
Journal Of Orthodontic Science
Presurgical management trends and nasoalveolar molding usage for infants with cleft lip and palate in the capital of a developing country
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BACKGROUNDS Nasoalveolar molding (NAM) application is among presurgical management (PSM) techniques used for infants with cleft lip and palate (CLP). It helps to approximate the palatal cleft and to reshape the nasoalveolar complex prior to primary lip repair. This study aimed to explore types of PSM and the dental speciality provision for infants with CLP in Baghdad. The status of NAM usage and surgeons’ perceptions toward NAM usage were assessed. MATERIALS AND METHODS This is a cross-sectional paper-based questionnaire study that collected responses of surgeons perform primary lip and nose repair regarding PSM. The questionnaire was distributed amongst public and private hospitals in Baghdad. Twenty surgeons were enrolled (only those su

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Publication Date
Tue Jun 01 2021
Journal Name
Baghdad Science Journal
The Existence of a Polynomial Inverse Integrating Factors and Studies About the Limit Cycles for Cubic, Quartic and Quintic Polynomial Systems
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Publication Date
Fri Nov 01 2019
Journal Name
Recent Technologies In Sustainable Materials Engineering
A Comparative Study Between the Individual, Dual and Triple Addition of (S.F.), (T.G.P.) and (P.V.A.) for Improving Local Gypsum (Juss) Properties
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Publication Date
Fri Nov 01 2013
Journal Name
Radioelectronics And Communications Systems
Erratum to: “BER Performance Enhancement for Secure Wireless Communication Systems Based on DCSK-MIMO Techniques under Rayleigh Fading Channel”
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There has been a growing interest in the use of chaotic techniques for enabling secure communication in recent years. This need has been motivated by the emergence of a number of wireless services which require the channel to provide low bit error rates (BER) along with information security. The aim of such activity is to steal or distort the information being conveyed. Optical Wireless Systems (basically Free Space Optic Systems, FSO) are no exception to this trend. Thus, there is an urgent necessity to design techniques that can secure privileged information against unauthorized eavesdroppers while simultaneously protecting information against channel-induced perturbations and errors. Conventional cryptographic techniques are not designed

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Publication Date
Fri Oct 04 2024
Journal Name
Analytical And Bioanalytical Chemistry Research
Optimization and Validation of a GC-FID/QuEChERS Method for Quantitative Determination of Spiromesifen Residues in Tomato Fruits, Leaves and Soil Matrices
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Pesticides serve a crucial function in contemporary farming practices, safeguarding agricultural crops against pest infestations and boosting production outputs. However, indiscriminate use has caused environmental and human health damage. This study aimed to develop and validate a gas chromatography-flame ionization detection (GC-FID) methodology for the direct and routine analysis of spiromesifen residues in soil, leaves, and tomato fruits. The proposed method prioritizes simplicity by avoiding derivatization steps, offering advantages over existing approaches that utilize lengthy multi-step extraction or derivatization prior to GC analysis. A key novelty of this work is the development of a QuEChERS extraction coupled directly to GC-FID

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Publication Date
Wed Jun 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
The most important challenges facing the Iraqi economyAnd ways to address them
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Facing the Iraqi economy, a number of economic challenges that threaten the future of Iraq and the security of economic, political and social, such as poverty, unemployment, inflation and the dilapidated infrastructure and rising production costs and administrative and financial corruption, environmental pollution, water problems and the deterioration of agricultural and industrial production, etc., and over the seriousness of these challenges, they are intertwined and overlapping and growing worse, without the corresponding adoption of state strategies that will develop appropriate solutions and appropriate to resolve those challenges because of concern the subject of security and terrorism, which requires the development of an

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Publication Date
Tue Mar 28 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Comparison between Rowatinex and Tamsulosin as a Medical Expulsion Therapy for Ureteral Stone
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The objective of this study is to evaluate the efficacy and safety of rowatinex and tamsulosin in the treatment of patients with ureteric stone.

Forty patients with ureteric stone ranged (4- 12) mm, were included in this study. They were randomized into two groups where the first group includes twenty patients treated with Rowatinex three times daily (Group 1), and the second group includes twenty patients treated with tamsulosin 0.4mg/day (Group 2). All patients were randomly assigned to receive the designed standard medical therapy for a maximum of 3 weeks.

Each group was given an antibiotic as prophylaxis and an injectable non-steroidal anti-inflammatory drug used on demand. At the outpatient clinic all subjects were a

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Publication Date
Thu May 11 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Mammographic Doses Measurement for A Thick Compressed Breast and the Relationship Between Them
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   This study was done in Baghdad teaching Hospital by using developed instrument type GIOHO and included a number of patients with compressed breast thickness (7,8,9,10)cm .

          The relationship between radiation dose and breast thickness was linear.  All results were compared with the international standered values that measured by the International Nuctear Agency and Europeon sources ,it was found that it is in consistance or has a little difference .

         The study showed that the mean absorbed dose may be determined by using TLD measurement below 10 mGy and the glandular dose was (1.45 mGy) and this can not b

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