The dynamic behavior of laced reinforced concrete (LRC) T‐beams could give high‐energy absorption capabilities without significantly affecting the cost, which was offered through a combination of high strength and ductile response. In this paper, LRC T‐beams, composed of inclined continuous reinforcement on each side of the beam, were investigated to maintain high deformations as predicted in blast resistance. The beams were tested under four‐point loading to create pure bending zones and obtain the ultimate flexural capacities. Transverse reinforcement using lacing reinforcement and conventional vertical stirrups were compared in terms of deformation, strain, and toughness changes of the tested beams. The inclination angles of the used lacing reinforcement with respect to the longitudinal reinforcement were 45° and 60°. The lacing reinforcement was efficient and participated actively in resisting the bending moments and shear forces at the same time. For the same diameter of lacing reinforcement, the 60° inclination angle imposed more ductility before failure than beams with lacing reinforcement of a 45° inclination angle. Moreover, the lacing bar diameter was more effective in improving the load‐carrying capacities when using the inclination angle of 45°. A finite element (FE) model was developed and validated using the experimental results based on the measured deformations and strains to conduct a parametric study. The investigated parameters included the effect of the arrangements of the applied loads, laced rebar diameter, inclination angle, tension reinforcement ratio, and concrete strength.
Laboratory studies were conducted at the biological control unit, college of Agriculture, University of Baghdad to evaluate some biological aspects of the predator Chilocorus bipustulatus (Coleoptera: Coccinellidae), which is considered one of the most important predators on many insect pests, especially the scale insect, Parlatoria blanchardi, (Homoptera: Diaspididae) on date palms. The results showed that biological parameters of the predator were varied according to different degree of temperature. Egg incubation period was significantly different and reached to 7.5 and 5.44 day at 25 and 30°C respectively, Fertility was the same 100% at both temperature degrees. Larval growth periods were 17.41 and 16.12 day as well as the mortality
... Show MoreThis study aims to investigate the academic leaders’ perceptions towards the degree of availability of the dimensions of organizational immunity systems at the University of Tabuk, as well as to reveal the statistically significant differences between the average responses of the study sample members about the degree of availability of these dimensions at their university due to the variables of (gender, leadership position, and college specialization). To achieve the objectives of the study, a descriptive survey method was used. The study population consisted of (200) male and female leaders who were academic leaders at the University of Tabuk. A questionnaire was used as a tool for collecting data, which its validity and reliability
... Show MoreThe current research's problem includes the impact of cognitive reappraisal and reformulate on self-experience of emotional response and its negative feelings and the activity of cognitive reappraisal in changing response. The aim of this research is to detect the relation between adaptive response and cognitive reappraisal upon students of secondary school, and to find differences in gender and stage. The sample contained male and female student for the year(2022-2023) and consists of (480) students (240) male and (240) female in the karkh education/ 1 To achieve this aims researcher used descriptive method and to measure the two variables researcher built a scale for adaptive response according to theory of compound emotion (Barrett,20
... Show Morentroduction. Finding a safe innate immune response stimulator is one of the greatest challenges facing immunologists and vaccine manufacturers. Gap statement. The role of sterile bacterial secretions (SBSs) of Pseudomonas aeruginosa in stimulating the innate immune response was not investigated previously. Aim. The comparative effect of SBSs and bacterial cells of P. aeruginosa isolates isolated from freshwater (PAE) and infected wounds (PAC) on the respiratory tract innate immune response. Methodology. Four test mice groups were instilled intranasally (i.n.) with 106 c.f.u of PAC, 106 c.f.u of PAE, SBS of PAC, and SBS of PAE. Two control groups were given i.n. either LB broth or PBS. Time-course changes in IL-1 beta mRNA, TNF-alpha mRNA, I
... Show MoreDue to the potential cost saving and minimal temperature stratification, the energy storage based on phase-change materials (PCMs) can be a reliable approach for decoupling energy demand from immediate supply availability. However, due to their high heat resistance, these materials necessitate the introduction of enhancing additives, such as expanded surfaces and fins, to enable their deployment in more widespread thermal and energy storage applications. This study reports on how circular fins with staggered distribution and variable orientations can be employed for addressing the low thermal response rates in a PCM (Paraffin RT-35) triple-tube heat exchanger consisting of two heat-transfer fluids flow in opposites directions throug
... Show MoreGlass fiber–reinforced polymer (GFRP) reinforcement provides an effective alternative to conventional steel in concrete structures due to its corrosion resistance. Nevertheless, the lower elastic modulus of GFRP necessitates careful consideration of serviceability behavior in GFRP-reinforced concrete members. This study presents a numerical sectional analysis model for predicting the flexural response and ultimate capacity of hybrid reinforced concrete beams incorporating embedded GFRP profiles in combination with either mild steel or GFRP reinforcement bars under monotonic static loading. The proposed model employs realistic nonlinear stress–strain relationships for concrete and steel, together with secant moduli of elasticity
... Show MoreIn this paper, the dynamic behaviour of the stage-structure prey-predator fractional-order derivative system is considered and discussed. In this model, the Crowley–Martin functional response describes the interaction between mature preys with a predator. e existence, uniqueness, non-negativity, and the boundedness of solutions are proved. All possible equilibrium points of this system are investigated. e sucient conditions of local stability of equilibrium points for the considered system are determined. Finally, numerical simulation results are carried out to conrm the theoretical results.
Braces in straight bridge systems improve the lateral-torsional buckling resistance of the girders by reducing the unbraced length, while in horizontally curved and skew bridges, the braces are primary structural elements for controlling deformations by engaging adjacent girders to act as a system to resist the potentially large forces and torques caused by the curved or skewed geometry of the bridge. The cross-frames are usually designed as torsional braces, which increase the overall strength and stiffness of the individual girders by creating a girder system that translates and rotates as a unit along the bracing lines. However, when they transmit the truck’s live load forces, they can produce fatigue cracks at their connection
... Show More