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Optimizing the project quality is considered a quality-cost trade-offs problem for the project, because when increasing the quality of a project, it will require other resources that cause additional costs. The importance of the quality- cost trade-offs problem for the project lies in satisfying the project management in terms of optimizing the project quality and providing money from the additional cost allocated to the quality optimization process. The purpose of this study is to design an algorithm that gives a solution to the quality-cost trade-offs problem that represents the optimal solution or the best feasible solution for decision makers. After great effort, the first technique for quality optimization (FTQO) was designed in order to optimize the project quality with the lowest added costs, which is based on the graph of the project network in its work methodology. The quality of any project is usually determined by the quality associated with its sensitive activities, so in the process of optimizing project quality by using FTQO the focus is on sensitive activities located along the sensitive path in the graph of the project network. Therefore, FTQO has shown positive results and is very helpful in making the best decision for quality-cost trade-offs problem. Where the FTQO was characterized by clear and simple steps that can be conducted within an acceptable time for any size to the problem. [ABSTRACT FROM AUTHOR]

Because of laminated composites exceptional properties including high strength relative to weight ratio, strongly electrical insulation, and capacity to transmit load, they are being seriously considered to replace traditional materials for structural applications. In a previous study, the effect of layer arrangement on the mechanical properties of multilayered composites was studied and it turned out the setup (GF, KF, and CF) to be the best arrangement. The current study investigates at the way silicon carbide hybridization influences the tension and compression of the epoxy resin composites for the best arrangement. The composites were made using a hand lay-up technique at seven different degrees of reinforcement (2, 4, 6, 8, 10, 12, and 14 percentages of weight (wt%)). The extracted results showed that the tensile load, as well as yield stress for many composites containing silicon carbide nanoparticles increase linearly with particle loading. As particle loading increases, both increase the tension and compression strengths. There are a few abnormalities related to aggregating of nanoparticles with increased particle loading and the creation of micro voids. Even with some nanoparticle percentages (8-10%), notable advancements were achieved in composite mechanical characteristics, higher percentages (>10%) contributed in a lesser amount improvement. A number of preset criteria, involving strain, stress, and displacement distributions have been met by the convergent process of finite element analysis with ABAQUS software. [ABSTRACT FROM AUTHOR]

The current work focuses on the manner in which silicon carbide hybridization affects the impact, bending, and hardness testing of silicon carbide particle-reinforced hybrid epoxy composites. Hand lay-up approach was used to create the composites at seven various levels of reinforcement (2, 4, 6, 8, 10, 12, and 14 weight percentage (wt %). The extracted results showed the weight percentage (10 %) has higher impact strength than the other percentages and so it means absorb more energy than the other recipe due to high impact strength (241.61 N). In flexural test, the weight percentage (10%) of the ideal configurations (GF, KF, and CF) have higher flexural strengths (1.56 KN) compared to other percentages. The results from the experiments and the finite element models coincided well, and the simulations accurately predicted the failure processes in the specimens that were tested under flexural stress and impact. Due to its ability to absorb more energy than they allow a body to transmit, silicon carbide nanoparticles are suitable for body armor and vests used by military and police personnel. [ABSTRACT FROM AUTHOR]

In this work, aluminum alloy AA6061-T6 with a thickness of 1.5 mm is lap-joined with a polymer, High-Density Polyethylene (HDPE) with 4 mm using the friction lap joining (FLJ) technique. To increase the pore size, the aluminum alloy surface area underwent the anodizing process. The effects of joining factors such as transverse speed (50, 70, 90, and 160 mm/min) and rotational tool speed (920 and 1500 rpm) were examined. Tensile shear, Scanning Electron Microscopy (SEM), and the X-Ray Diffraction test (XRD) were all performed on each specimen. Two different failure types were noted; the first involved the lap joint (shear), while the second involved the side polymer. According to the most recent failure, the anodized process produced a good pore size where the melted polymer could pass through it. This suggests that the transverse and rotating speed processing factors impact joint efficiency. The highest joint performance is at 1500 rpm and 70 mm/min. The outcomes of the design of experiments are analyzed using the Minitab application. The shear force for joints was shown to be most affected by transverse speed. In the re-solidification zone, the interaction between aluminum and polymer is clearly visible. According to the SEM test, the bonding zone has a depth of roughly 17 µm. Additionally, the analysis's findings showed that for the Al/HDPE joint, this layer was primarily made of oxygen and aluminum. Aluminum and AL2O3 make up most of the phases, according to the XRD study. [ABSTRACT FROM AUTHOR]

This paper investigated the seismic behavior of a laboratory model for a raft foundation of a seven-story building resting on loose fine sandy soil before and after improvement using the cement grouting technique as liquefaction and settlement countermeasures. A shaking table device with a single degree of freedom using three earthquake time histories is utilized for simulating earthquake effects. The soil improvement was implemented by jet grouting columns (using ordinary Portland cement with a W/C ratio equal to unity) injected by a locally manufactured laboratory setup. The results of improved soil by the cement grouting technique have sustainable and geotechnical beneficial effects on the seismic response of the system during earthquake loads. [ABSTRACT FROM AUTHOR]

At this research, a detailed analysis of 25 field trials on various piles driven in various locations in Iraq between 1990 and 2021 is presented. To assess each pile's capacity to support a pile, this study uses six unique methods. These are actions (Davison offset limit, Chin konder, Brinch Hansen 80 percent, De court, De Beer, Fuller&Hoy and Butler &Hoy) Analysis has demonstrated that the failure of the pile will occur when the settlement reaches 0.5 mm and 25% of the design load is applied. may be foreseen with pile testing, permitting the required action to be taken before the pile falls. The Brinch Hansen 80 percent approach can be used to test trial and operational piles. Furthermore, with little settlement, the De Beer and modified Chin Knoder techniques provide a tolerable maximum load capacity. [ABSTRACT FROM AUTHOR]

In this paper, single- and double-stage RF rectifiers operating at 433 MHz and 915 MHz for wireless implantable devices were designed. The designed circuits were simulated by using ADS simulation tools. The circuit is simulated on a FR-4 substrate layer with dielectric constant of 4.1 and a thickness of 1.6 mm. In addition, microstrip lines were added to the circuit to connect the circuit elements and mimic the real case and achieve more accurate results. The results showed that the achieved output voltage of the singe stage rectifier was around 3.5 V with a total conversion efficiency up to 60 %. On the other hand, the 915 MHz rectifier was able to provide an output voltage of more than 1 V and a conversion efficiency of 7%. The contribution of this work is the attempt to compare the performance of the same RF rectifier but at different frequency bands. [ABSTRACT FROM AUTHOR]

The main aim of the present investigation is to estimate the risks of ionization radiation exposure. This is performed by assessing the relationship between the intensities of ionization radiation exposure and the level of expression of the forkhead box P3 (FOXP3), which is expected to amplitude the fundamental hazards that radiological employees are subjected to. The current investigation was initiated in August and finished in December 2019. The study matrix consists of 60 contributors. These contributors were categorized into two main groups: radiographers (30 contributors) and healthy members as a control group (30 contributors). A complete blood picture analysis, FOXP3 level, and ESR were acquired by obtaining blood samples for all contributors. The dose equivalents of personal radiation were determined for all radiographers. The results of FOXP3 expression level for radiographers (p<0.0001) were remarkably higher than those obtained for the healthy contributors. In addition, it was noticed that the FOXP3 expression was positively related to personal radiation dose. The study showed that there is still a significant radiation risk even under well-prepared radiation protection. [ABSTRACT FROM AUTHOR]

This paper presents an adaptive Digital Predistorter (DPD) to handle the nonlinearity and memory challenges that effect the transmitted signal in High Power Amplifier (HPA) system. The proposed scheme first handles the nonlinearity effect by estimating the reverse error, then the obtained signal is processed by the FIR filter to diminish the memory effect. The simulation results of the proposed method present a superior performance compared with state-of-the-art methods used in compensating nonlinearity and memory effects. These results suggest that the proposed approach is more suitable to transmit a standard signal with less error by using traditional HPA. [ABSTRACT FROM AUTHOR]

Here research portrays the execution as well as activity highlights for a "Phase-Locked Loop" ("PLL") engineering established frequency synthesizer for clock age also, computerized schemes running. From a programmed design, seeing an entry source frequency FREF=30 MHz, also, the synthesized waveform frequency will be 100 MHz. In the wake of producing the reproduction beside such qualities, one may next alter these values through introducing advanced qualities in the "MATLAB® Command Window", assuming one need to test beside this scheme. This model tells the best way to reproduce a "phase-locked loop (PLL) frequency synthesizer". The scheme duplicates the (fsynFr) source signal frequency using a steady synN/synM, to deliver an integrated wave have a frequency of synFr*synN/synM. A criticism loop keeps up with the synthesized wave frequency on such stage. [ABSTRACT FROM AUTHOR]

High strength concrete (HSC) posses more problems, since it has less ductility in comparison with normal strength concrete (NSC). To overcome this problem was reinforced with fibers and hybrid fibers. The effects of fibers and hybrid fibers upon the properties of high-strength concrete mixtures containing superplasticizing admixtures have been investigated. The properties of fibrous high-strength concrete and high-strength concrete are compared. Results showed that decrease in workability of all concrete mixtures containing polypropylene, glass and hybrid fibers compared with control mix. It was found that the addition polypropylene fibers increase the suitable w/c ratio to save the workability from 0.24 to 0.26, 0.27 and 0.29 at 0.5, 1.0 and 1.5 volume fraction respectively. While the w/c ratio increased to 0.35 when the 0.4% glass fiber was added. HSC with 1.5% polypropylene fibers showed superior splitting and flexural strengths over the other concrete without or with fibers, compared with HSC without fibers the increasing were 30.76% and 25.61% respectively. At 28-day age, fibrous high-strength concrete showed higher compressive, splitting and flexural strengths than the high-strength concrete, depending upon the types and volume fraction of fibers. The results obtained demonstrate that the addition of the hybrid fibers to the high strength concrete showed that the ratio of (0.7% polypropylene+0.12% glass fibers) at volume fraction 0.82% gives better fresh and hardened properties than the ratio (0.3% polypropylene+0.28% glass fibers) at volume fraction 0.58%. The maximum increase in compressive strength, splitting strength and flexural strength of high strength concrete contains (0.7% polypropylene+0.12% glass fibers) were 9.57%, 15.38% and 14.04% respectively. [ABSTRACT FROM AUTHOR]

Flour is a powder made from grains such as wheat, barley, rice, etc., or any crops rich in starch, also flour is the main raw material in making basic foods such as bread. because of the increased incidence of cancer, this study was conducted to assess the concentration of radionuclide specific activity concentration in the most common food in Iraq (different types of Cereal flour) and to estimate its radiative forcing in the long term. For this purpose, the ratio (232Th - 226Ra , 40K - 226Ra , 40K - 232Th) were measured in 16 cereal flour samples using a gamma ray spectrometer with average values (0.153 , 34.550 , 227.810) respectively, the result showed that the ratio concentration values (40K - 226Ra), (40K - 232Th) were higher than the average worldwide. also calculated some hazard indices alpha index(Iα) gamma index(Iγ), indoor absorbed dose(Din), outdoor absorbed dose (Dout) ,annual gonadal equivalent dose (AGED) , the annual committed effective ingestion dose (AED) , finally found cancer risk (for adult, children , infant and workers which were (0.0001, 1.16E-04 , 3.64E-06 and 0.00077) respectively within the permissible limits. The radiation hazard indexes for all samples were lower than the satisfactory values. [ABSTRACT FROM AUTHOR]

In this research, AgAl1-xInxSe2 (AAIS) compound alloys prepared for different x (0.3, 0.6 and 0.9) by melting them in an evacuated quartz tube (2.5*10-3 torr). AAIS with different Indium concentrations x (0.3, 0.6 and 0.9), t=750±30nm thin films deposited by thermal evaporation method with deposition rate (5±0.1) nm sec-1 on glass and p-type silicon substrates to study structural, optical, electrical properties and to fabricate solar cells. From energy dispersive x-ray spectrometer (EDS) found the amount or (concentration) of the elements (Ag, Al, In, Se) of alloys, to studying the topography, estimate the surface roughness and average grain size was used AFM technique, the results show that the grain size increase with In-content increase. Optical measurements show that the preparation AAIS thin films have high absorption in visible range. The allowed direct energy gap was decreases with increase In-content. All films were N-type while the concentration of the charge carriers increases. The optimum condition of efficiency (η =5.32). Under illumination found where (x=0.6, t=750±30 nm) [ABSTRACT FROM AUTHOR]

Pure SnSe thin film and doped with S at different percentage (0,3,5,7)% were deposited from alloy by thermal evaporation technique on glass substrate at room temperature with 400±20nm thickness.The influences of S dopant ratio on characterization of SnSe thin film Nano crystalline was investigated by using Atomic force microscopy(AFM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), Hall Effect measurement, UV-Vis absorption spectroscopy to study morphological, structural, electrical and optical properties respectively.The XRD showed that all the films have polycrystalline in nature with orthorhombic structure, with preferred orientation along (111)plane.These films was manufactured of very fine crystalline size in the range of (18.167-51.126)nm, depending on the S ratio doping, the results of AFM indicated that these films were Nano crystalline with grain size (60.12-84.25)nm.Direct band gap values with range(1.5-1.68)eV were gotten from optical absorption measurements. I-V characteristics for p- SnSe:S/n-Si heterojunctions show the efficiency of solar cell increase with increase doping ratio and the highest value at films doped with ratio (7%S). C-V measurements show that all junctions were an abrupt type. [ABSTRACT FROM AUTHOR]

AlSb thin-film solar cell consisting of p-type AlSb was prepared on n-type Si substrate by using thermal evaporation. The effect of the preparation and partial replacement of Aluminum with Indium of the Al1-xInxSb were studied to obtain the best properties. Thin films have been deposited on glass substrate at R.T with ratios (X=0.0, 0.1 and 0.3) under the vacuum of 10-6 Torr with (150) nm thickness. Structural, optical and electrical properties of the films were investigated, I-V characteristics studies as ratios of Indium increased, measurements indicate formation of good quality thin films of AlSb having band gap within the range reported in the literature. [ABSTRACT FROM AUTHOR]

Cadmium Sulphide (CdS) thin films were equipped by thermal evaporation at thickness t (500±30) nm then doped with Silver (Ag) with ratios (X=0.0, 0.01, 0.03 and 0.05). The Substrates were used glass and single crystal silicon substrate with the direction (111) of the (p-type) to study the (structural, optical and photoelectric) properties. The ratios of alloy studied by EDS and the thin films structure deliberate by X-ray diffraction were a polycrystalline cubic phase. Direct band gap values with rang (2.4 eV -2.25 eV) were gotten from optical absorption measurements. The photo detector is shown height responsivity and touched at (0.43 A/W) with the bias voltages of (4V) and the detectivity of the fabricated CdS: Ag/Si UV detector at a wavelength of 551 nm is found to be 2.58244x1011cm Hz 1/2 W−1. [ABSTRACT FROM AUTHOR]

In this work, Bi2O3 was deposited as a thin film of different thickness (400, 500, and 600 ±20 nm) by using thermal oxidation at 573 K with ambient oxygen of evaporated bismuth (Bi) thin films in a vacuum on glass substrate and on Si wafer to produce n-Bi2O3/p-Si heterojunction. The effect of thickness on the structural, electrical, surface and optical properties of Bi2O3 thin films was studied. XRD analysis reveals that all the as deposited Bi2O3 films show polycrystalline tetragonal structure, with preferential orientation in the (201) direction, without any change in structure due to increase of film thickness. AFM and SEM images are used to investigate the influences of film thickness on surface properties. The optical measurement were taken for the wave length range (400-1100) nm showed that the nature of the optical transition has been direct allowed with average band gap energies varies in the range of (2.9-2.25) eV with change thickness parameter. The extent and nature of transmittance, absorbance, reflectance and optimized band gap of the material assure to utilize it for photovoltaic applications. Hall measurements showed that all the films are n-type. The electrical properties of n-Bi2O3/p-Si heterojunction (HJ) were obtained by I-V (dark and illuminated) and C-V measurement at frequency (10 MHz) at different thickness. The ideality factor saturation current density, depletion width, built-in potential and carrier concentration are characterized under different thickness. The results show these HJ were of abrupt type. The photovoltaic measurements short-circuit current density, open-circuit voltage, fill factor and efficiencies are determined for all samples. Finally thermal oxidation allowed fabrication n-Bi2O3/p-Si heterojunction with different thickness for solar cell application. [ABSTRACT FROM AUTHOR]

The aim of the present work is studing the influence of gamma irradiation on the superconducting properties of TlBr2Ca2Cu3O9-δ compound, at room temperature by using 137Cs source with dose 10,20 and 30 MRad. Specimen has been prepared by solid state reaction process. Superconductor properties and X-ray diffraction (XRD) studied before and after irradiation. It is showed that our compound has tetragonal structure correspond to the 1223 phase with decreasing of the ratio c/a due to gamma irradiation. In addition, the transition temperature (Tc(on)&Tc(off)) were decreasing from 110 to 85 K, and 129 to 117 K respectivelya, when the dose increasing from 0 to 20 MRad and increase Tc(on) to 119 K &Tc(off 132 for dose 30 MRad. [ABSTRACT FROM AUTHOR]