The studies on unbonded post-tensioned concrete members strengthened with Carbon Fiber Reinforced Polymers (CFRPs) are limited and the effect of strengthening on the strain of unbonded pre-stressed steel is not well characterized. Estimating the flexural capacity of unbound post-tensioned members using the design methodology specified in the design guidelines for FRP strengthening techniques of bonded post-tensioned members does not provide a reliable evaluation. This study investigates the behavior of unbonded post-tensioned concrete members with partial strand damage (14.3% and 28.6% damage) and strengthened with CFRP laminates using a near-surface mounted technique with and without U-wrap anchorages. The experimental results showed that the use of CFRP laminates significantly affects strand strain, especially with the use of anchors. The CFRP reinforcement affected flexural strength, crack width, and midspan deflection. However, the flexural stiffness of strengthened members during the serviceability phases is critical as strand damage ratios increase. In comparison with the nondamaged girder, the NSM-CFRP laminates enhanced the flexural capacity by 11% and 7.7% corresponding to strand damage of 14.3% and 28.6% respectively. Additionally, semiempirical equations were proposed to predict the actual strain of unbonded strands whilst considering the effects of FRP laminates. The suggested equations are simple to apply and provide accurate predictions with little variance.
Data steganography is a technique used to hide data, secret message, within another data, cover carrier. It is considered as a part of information security. Audio steganography is a type of data steganography, where the secret message is hidden in audio carrier. This paper proposes an efficient audio steganography method that uses LSB technique. The proposed method enhances steganography performance by exploiting all carrier samples and balancing between hiding capacity and distortion ratio. It suggests an adaptive number of hiding bits for each audio sample depending on the secret message size, the cover carrier size, and the signal to noise ratio (SNR). Comparison results show that the proposed method outperforms state of the art methods
... Show MoreIron–phthalocyanine (FePc) organic photoconductive detector was fabricated using pulsed laser deposition (PLD) technique to work in ultraviolet (UV) and visible regions. The organic semiconductor material (iron phthalocyanine) was deposited on n-type silicon wafer (Si) substrates at different thicknesses (100, 200 and 300) nm. FePc organic photoconductive detector has been improved by two methods: the first is to manufacture the detector on PSi substrates, and the second is by coating the detector with polyamide–nylon polymer to enhance the photoconductivity of the FePc detector. The current–voltage (I–V) characteristics, responsivity, photocurrent gain, response time and the quantum efficiency of the fabricated photoconduc
... Show MoreCopper doped Zinc oxide and (n-ZnO / p-Si and n-ZnO: Cu / p-Si) thin films thru thickness (400±20) nm were deposited by thermal evaporation technique onto two substrates. The influence of different Cu percentages (1%,3% and 5%) on ZnO thin film besides hetero junction (ZnO / Si) characteristics were investigated, with X-ray diffractions examination supports ZnO films were poly crystal then hexagonal structural per crystallite size increase from (22.34 to 28.09) nm with increasing Cu ratio. The optical properties display exceptional optically absorptive for 5% Cu dopant with reduced for optically gaps since 3.1 toward 2.7 eV. Hall Effect measurements presented with all films prepared pure and doped have n-types conductive, with a ma
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The public procurement crisis in Iraq plays a fundamental role in the delay in the implementation of construction projects at different stages of project bidding (pre, during, and after). The procurement system of any country plays an important role in economic growth and revival. The paper aims to use the fuzzy logic inference model to predict the impact of the public procurement crisis (relative importance index and Likert scale) was carried out at the beginning to determine the most important parameters that affect construction projects, the fuzzy analytical hierarchy process (FAHP) to set up, and finally, the fuzzy decision maker's (FDM) verification of the parameter for comparison with reality. Sixty-five
... Show MoreIn this paper, we study the incorporation of the commensalism interaction and harvesting on the Lotka–Volterra food chain model. The system provides one commensal prey, one harvested prey, and two predators. A set of preliminary results in local bifurcation analysis around each equilibrium point for the proposed model is discussed, such as saddle-node, transcritical and pitchfork. Some numerical analysis to confirm the accruing of local bifurcation is illustrated. To back up the conclusions of the mathematical study, a numerical simulation of the model is carried out with the help of the MATLAB program. It can be concluded that the system's coexistence can be achieved as long as the harvesting rate on the second prey population is
... Show MoreThe game of volleyball is one of the competitive team games that took the lead in terms of its spread in the world, and the game of volleyball relies on basic skills as an important base on which this game is built to advance in the level of performance Performance and among these skills the skill of spiking and blocking wall, the research aims to identify the extent of the relationship of decision-making to the performance of spiking and blocking in volleyball for junior players. The sample was chosen from volleyball players for the Junior Specialized School of Sulaikh Sports Club / Baghdad Governorate for the season 2020 The researcher used the descriptive approach, and the research community was composed of (101) players. The two
... Show MoreBackground: Environmental chemicals are thought to
adversely affect human reproductive function.
Objective : To estimate the concentration of cadmium(Cd)
, lead ( Pb ) and Zinc ( Zn ) in serum and seminal plasma
among infertile men .
Methods: A sample of 70 infertile men was investigated.
The relationship of trace elements concentration in serum and
seminal plasma was studied in relation to sperm density,
motility and sperm count.
Results: Except for Zinc the concentration of (Pb) and (Cd)
were generally higher in serum than in seminal plasma. The
mean concentration of (Zn) in seminal plasma was more than
25 times higher than in serum There were no statistical
significant differences observed in the
Back ground: The gender related difference
may be the result of pregandiol excretion in the
latter half of pregnancy.
Aim: This study is to evaluate the effects of fetal
gender on serum human chorionic gonadotropin
[HCG] and testosterone in normotensive and
preeclamptic pregnancies
Methods: The study consisted of fifty women with
singleton pergnancy in their third trimester. Twenty
five pregnancies were uncomplicated Among those
there were thirteen male, and twelve female fetuses
Twenty five pregnancies were complicated by
preeclampsia. Among those thirteen were with male,
and twelve were with female fetuses. Human
chorionic gonadotropin and total testosterone were
measured in maternal periphe