Hyperbolic P-Y Criterion for Cohesive Soils

Drilled shafts have been frequently used as a foundation to support lateral loads. The p-y method of analysis has been widely used for predicting the behavior of laterally loaded drilled shafts. The existing p-y criteria for cohesive soils are divided into soft or stiff clays, on the basis of a limited number of lateral load test results. Currently, there is no p-y criterion developed for cohesive intermediate geomaterial. In this paper, a hyperbolic equation for p-y curve is presented for cohesive soils and intermediate geomaterials. Based on 3-D FEM simulation results, a new empirical equation is presented for calculating the initial tangent to p-y curve. The proposed hyperbolic p-y criterion is verified by using the results of six full-scale lateral load tests on fully instrumented drilled shafts with diameters ranging from 0.76 m to 1.83 m in the geo-medium ranging from soft clays to intermediate geomaterial. The proposed hyperbolic p-y criterion is shown to be capable of predicting the loaddeflection and bending moments of the laterally loaded shafts for the six cases studied in this paper

A Software Evolution Process Model: Analysis of Software Failure Causes

This paper presents a study on the degree of impact of several components on the evolvability of software systems. In particular, it focuses on failure rates, testing, and other factors which force the evolution of a software system. Also, it studies the evolution of software systems in the presence of various failure scenarios. Unlike previous studies based on the system dynamic (SD) model, this study is modeled on the basis of actor-network theory (ANT) of software evolution, using the system dynamic environment. The main index used in this study is the destabilization period after the recovery from any failure scenario. The results show that more testing and quick recovery after failure are keys to a fast system return to stability

A Software Evolution Process Model: Analysis of Software Failure Causes

This paper presents a study on the degree of impact of several components on the evolvability of software systems. In particular, it focuses on failure rates, testing, and other factors which force the evolution of a software system. Also, it studies the evolution of software systems in the presence of various failure scenarios. Unlike previous studies based on the system dynamic (SD) model, this study is modeled on the basis of actor-network theory (ANT) of software evolution, using the system dynamic environment. The main index used in this study is the destabilization period after the recovery from any failure scenario. The results show that more testing and quick recovery after failure are keys to a fast system return to stability

Non-Linear Seismic Response of Base-Isolated Frame Structures Using Rubber Bearings

Over the past two decades, much progress has been made in research and application of the base isolation of structures as means of providing earthquake resistance to a structure. However, the trade-off between the extent of acceleration reduction and the response of a base-isolation system has not been given a serious consideration. This work uses a new material constitutive model for rubber bearing base-isolation system, which adopts the technique of real-time structural parameter modification. To achieve this, a finite element modeling and analysis are performed as a comparative study between a conventional totally fixed-base steel frame structure and similar base-isolated structures using rubber-steel bearings. The structures are subjected to the El-Centro, N-S earthquake. In order to include nonlinearity effects, a non-linear hyperviscoelastic material model has been used and linked to ABAQUS software as a user defined material subroutine (i.e., UMAT). Special connector elements are selected from ABAQUS library to connect the rubber bearings to the frame structure and the foundations in order to achieve the required kinematical constraints at the connection points. The model is validated by carrying out a comparative study of the results obtained from the analysis of the presented material model with those obtained by using the existing ABAQUS material models (e.g., Ogden material model). The results show a significance efficiency of using the rubber bearing isolation in order to uncouple the structure from the seismic ground motion. Moreover, it has been proved that the used material model is more effective to capture the behavior of the base-isolated structures expressing a notable reduction in acceleration and an increase in the structural resistance to earthquake excitations

Symmetrical and Anti-Symmetrical Buckling of Long Corroded Cylindrical Shell Subjected to External Pressure

This paper derives an exact analytical solution for determining elastic critical buckling pressures and mode shapes for very long corroded cylindrical steel shells subjected to external pressure considering symmetrical and anti-symmetrical mode cases. The corroded long cylindrical shell has been modelled as a non-uniform “stepped-type” ring consisting of two portions- corroded and un-corroded regions. A full range parametric study has been made to investigate the effect of corrosion angular extent and corrosion thickness on the elastic buckling pressures and their modes. The study shows that buckling loads and modes depend on the corrosion angular extent â and the corroded to un-corroded thicknesses ratio. The results are verified by a set of investigations with a series of corroded cylindrical shells. They showed a close agreement with those obtained from using the finite element package ABAQUS

Effect of Jordanian Steel Blast Furnace Slag on Asphalt Concrete Hot Mixes

Significant quantities of slag are generated as waste materials or by-product from steel industries. They usually contain considerable quantities of metals. In this study, steel slag obtained from a steel factory in Jordan was used in Asphalt Concrete Hot Mixes (ACHM). Marshall specimens were prepared with 100% lime stone dense graded aggregates at 4.5, 5, 5.5 and 6% bitumen contents by weight of aggregate to serve as control specimens. Another set of Marshall specimens with 100% Steel Slag Aggregates (SSA) and another set with a combination of limestone and (SSA) were prepared using the same grading and bitumen contents. Test results showed a reduction in the Optimum Bitumen Content (OBC) and an increase in density and stability values for specimens prepared with 100% (SSA). A decrease in the flow, Percentage of air voids (Pav), and Voids in Mineral Aggregates (VMA) values - but in compliance with the recommended values by the Asphalt Institute- was observed in specimens prepared with 100% (SSA)

Transient Mixed Convection Flow of A Second-Grade Visco-Elastic Fluid over a Vertical Surface

The viscoelastic boundary layer flow and mixed convection heat transfer near a vertical isothermal surface have been examined in this paper. The governing equations are formulated and solved numerically using an explicit finite difference technique. The velocity and temperature profiles, boundary layer thicknesses, Nusselt numbers and the local skin friction coefficients are shown graphically for different values of the viscoelsatic parameter. In general, it is found that the velocity decreases inside the boundary layer as the viscoelsatic parameter is increased and consequently, the local Nusselt number decreases. This is due to higher tensile stresses between viscoelsatic fluid layers which has a retardation effects on the motion of these layers and consequently, on the heat transfer rates for the mixed convection heat transfer problem under investigation. A Comparison with available published results on special cases of the problem shows excellent agreement

High prevalence of current tobacco smoking among patients with tuberculosis and people living with HIV in Jordan: A cross-sectional survey

INTRODUCTION Continued smoking by patients with tuberculosis (TB) and people living with HIV (PLHIV) leads to adverse treatment outcomes. Estimates of tobacco use among the population are scarce in the Eastern Mediterranean region, where the burden of TB and HIV is also low but highly variable. This study determined the prevalence of current smoking and assessed factors associated with current smoking among patients with TB and PLHIV in Jordan. METHODS We analyzed data from the Jordan Knowledge, Attitude, and Practices survey in 2021. Information on current tobacco use, including products and frequency of smoking, was collected from 452 patients with TB and 152 PLHIV. We performed multivariable logistic regression to assess the sociodemographic characteristics independently associated with current smoking.RESULTS Prevalence of current smoking was 43.8% among TB patients and 67.8 % among PLHIV, and conventional cigarettes were the most used tobacco products. The prevalence of current smoking among patients with TB was higher among males (AOR=8.20; 95% CI: 5.05-13.32), Jordanians (AOR=5.37; 95% CI: 2.66- 10.86) and Syrians (AOR=4.13; 95% CI: 1.60-10.67), and those experiencing financial difficulties (AOR=2.83; 95% CI: 1.69-4.74). The prevalence of current smoking among PLHIV was higher in those with financial difficulties (AOR=3.13; 95% CI: 1.19-8.27). CONCLUSIONS Nearly half of the patients with TB and PLHIV were current tobacco smokers, higher than the general population. There is an urgent need to investigate the reasons for such a high smoking prevalence and introduce and strengthen smoking cessation services under the TB and HIV control programs

WORKPLACE SEXUAL HARASSMENT AND WITHDRAWAL BEHAVIORS AMONG FEMALE WORKERS IN JORDANIAN HOTELS, THE MEDIATING ROLE OF EMOTIONAL EXHAUSTION

This study explores the connection between workplace sexual harassment and the tendency of female hotel workers in Jordan to withdraw from their jobs, with a specific focus on the role of emotional exhaustion. The study involved female employees from five-star hotels in Amman, Jordan, using a convenience sampling approach, and collected 203 valid responses, achieving an 87% response rate. Using Structural Equation Modeling (SEM), the research found that sexual harassment and emotional exhaustion directly and positively affected withdrawal behaviors. Notably, sexual harassment had a substantial positive impact on emotional exhaustion. However, the study found that emotional exhaustion did not mediate the relationship between sexual harassment and withdrawal behaviors. The coefficients of determination (R2) for emotional exhaustion and withdrawal behaviors were 0.780 and 0.841, respectively. This study underscores the prevalence of sexual harassment in Jordanian hotel workplaces, especially among female employees. It highlights that sexual harassment significantly contributes to emotional exhaustion among female workers, which, in turn, affects their inclination to leave their jobs. This emphasizes the importance of maintaining motivated and engaged female employees within the hospitality industry