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This study aims to discuss the determination of the unknown in-plane mechanical material properties of printed circuit boards (PCBs) by correlating the results from dynamic testing and finite element (FE) models using the response surface method (RSM).

The first 10 resonant frequencies and vibratory mode shapes are measured using modal analysis with hammer testing experiment, and hence, systematically compared with finite element analysis (FEA) results. The RSM is consequently used to minimize the cumulative error between dynamic testing and FEA results by continuously modifying the FE model, to acquire material properties of PCBs.

Great agreement is shown when comparing FEA to measurements, the optimum in-plane material properties were identified, and hence, verified.

This paper used FEA and RSMs along with modal measurements to obtain in-plane material properties of PCBs. The methodology presented here can be easily generalized and repeated for different board designs and configurations.

This paper aims to investigate and compare the reliability performance of land grid array (LGA) and ball grid array (BGA) solders, as well as the SAC105 and 63Sn37Pb solder alloys, in vibration loading conditions.

Reliability tests were conducted using a sine dwell with resonance tracking vibration experiment. Finite element simulations were performed to help in understanding the observed failure trends.

Reliability results showed that the tin-lead solders out-perform lead-free solders in vibrations loading. Additionally, the LGA solder type could provide a better vibration reliability performance than BGA solders. Failure analysis results showed that in LGAs, the crack is initiated at the printed circuit board side and at the component side in BGAs. In both types, the crack is propagated throughout in the intermetallic compound layer.

In literature, there is a lack of published data in the comparison between LGA and BGA reliability performance in vibration loadings. This paper provides useful insights in the vibration reliability behavior of the two common solder joint types.

This paper aims to investigate the fatigue life performance of SAC305 ball grid array solders under combined temperature and harmonic vibration loading conditions.

Fatigue tests were performed using a sine dwell with resonance tracking vibration and temperature loading experiment. Finite element stress analysis was also performed to help in understanding the observed failure trends.

Fatigue test results showed that the lead-free solders tend to fail quickly in higher temperatures and higher vibration loading test conditions. The failure analysis results revealed that in low temperatures, the solder cracks are initiated and propagated at the package side. However, in high temperatures, the cracks are observed at the board side of the interconnect. In all conditions, the cracks are propagated throughout the intermetallic compound layer.

In the published literature, there is a lack of data in the area of fatigue assessment of lead-free solders under combined temperature and vibration loadings. This paper provides useful insights into combined thermal/vibration fatigue, i.e. reliability behavior of lead-free solder joint types.

This paper aims to present a reliability performance assessment of electronic packages subjected to harmonic vibration loadings by using a statistical factorial analysis technique. The effects of various geometric parameters, the size and thickness of the printed circuit board and component and solder interconnect dimensions on the fundamental resonant frequency of the assembly and the axial strain of the most critical solder joint were thoroughly investigated.

A previously published analytical solution for the problem of electronic assembly vibration was adopted. This solution was modified and used to generate the natural frequency and solder axial strains data for various package geometries. Statistical factorial analysis was used to analyze these data.

The results of the present study showed that the reliability of electronic packages under vibration could be significantly enhanced by selecting larger and thicker printed circuit boards and thinner and smaller electrical components. Additionally, taller and thinner solders might also produce better reliability behavior.

The results of this investigation can be very useful in the design process of electronic products in mechanical vibration environments.

One difficultly in building an effective finite element (FE) model of a board-level package is because of complex structure of the printed circuit board (PCB), as it contains copper layers, woven fabrics, plated-through holes and so forth. Therefore, it is often acceptable to obtain equivalent orthotropic material properties and use them in the simulation. This paper aims to provide a research methodology to produce equivalent FE models for board-level electronic packages.

In this methodology, the FE models’ data were correlated with experimental modal analysis results in terms of natural frequencies and mode shapes. Statistical factorial analysis was used to examine the electronic assembly material properties effect on the structure’s resonant frequencies. The equivalent material properties of the PCB were adjusted using the optimization tool available in ANSYS software for free boundary conditions. The equivalent FE model was then validated for the fixed boundary conditions.

The resultant FE models were in great match with the measured data in terms of resonant frequencies and mode shapes. The so-developed models can be further used in the analysis of the dynamic response of the electronic packages and solder interconnects.

The current approach provides a sophisticated research methodology to provide high-accuracy FE models of electronic assemblies subjected to vibration. The main value of this approach is to first test the effect of each material property on the package dynamic characteristics before starting the correlation process, then to automate the correlation algorithm using the built-in FE model updating feature available in ANSYS software.

This paper aims to examine the thermal cycling fatigue life performance of two-common solder array configurations, full and peripheral, using three-dimensional nonlinear finite element analysis.

The finite element simulations were used to identify the location of the critical solder interconnect, and using Darveaux's model, solder thermal fatigue life was computed.

The results showed that the solder array type does not significantly influence thermal fatigue life of the interconnect. However, smaller size packages result in improved life by almost 45% compared to larger package designs. Additionally, this paper provided an engineered study on the effect of the number of rows available in a perimeter array component on solder thermal fatigue performance.

General design recommendations for reliable electronic assemblies under thermal cycling loaded were offered in this research.

The purpose of this paper is to investigate the strain concentration factor in a central countersunk hole riveted in rectangular plates under uniaxial tension using finite element and response surface methods.

In this work, ANSYS software was elected to create the finite element model of the present structure, execute the analysis and generate strain concentration factor (,) data. Response surface method was implemented to formulate a second order equation to precisely compute (,) based on the geometric and material parameters of the present problem.

The computations of this formula are accurate and in a great agreement with finite element analysis (FEA) data. This equation was further used for obtaining optimum hole and plate designs.

An optimum design of the countersunk hole and the plate that minimizes the (,) value was achieved and hence validated with FEA findings.

This paper aims to thoroughly investigate the free vibration characteristics of rectangular plates resting on symmetrically distributed four rigid supports by using a finite element (FE) method.

ANSYS parametric design language was used to generate the FE models and to run the analysis. The FE models were initially validated and were then used to solve for the plate first natural frequency and mode shape. The effect of the plate aspect ratio and support location on the free vibration properties of the plate was thoroughly studied by conducting several FE runs. Finally, simple empirical formulas were developed to conveniently calculate the plate first natural frequency based on the geometric parameters and support type, as well as support locations. Those well-formulated equations were in a great match with the FE data.

The results showed that the plate first natural frequency and mode shape are highly affected by the plate size and support locations. Specifically, the natural frequency deceases as the plates becomes larger. Also, the bending behavior of the first mode is highly affected by the support location, which results in a significant change in the natural frequency of the plate structure. In addition, the presently formulated empirical formulas are faithfully able to predict the natural frequency of the plate based on the geometric parameters and support location.

This paper provides numerous new data on the vibration properties of the rectangular plate resting on rigid supports. Also, it provides a simple way to easily calculate the natural frequency of this plate problem, unlike the very limited and complicated analytical solutions available in literature.

This study aims to identify and explore experiences, perspectives, barriers and enablers to women’s career progression to management positions in the health-care sector and to assess women’s and men’s perceptions of the policies and practices of the health-care system concerning gender equality and nondiscrimination between women and men.

A cross-sectional survey was conducted among health-care professionals in ten selected hospitals, including physicians, registered nurses/midwives and pharmacists with or without managerial positions.

This study included a total of 2,082 female and 1,100 male health-care professionals. Overall, 70% of women and men reported that opportunities for advancement are based on knowledge and skills in their institution. However, 58.9% of women (p < 0.001) reported that women are more likely to face barriers to career advancement than men do in their workplace. Lack of women in general/line management and discrimination against women by supervisors at the point of promotion were the main barriers to women's career progression, as they were reported by two-thirds of women. The main barrier, as perceived by men (62.3%) was that women have family and domestic responsibilities.

To overcome barriers in women's career progression, there is a need to establish a career planning and capacity-building program for women in the health sector.

Jordanian female health-care professionals face different barriers that affect their career progression, including inequity and discrimination in the workplace, negative views about women’s abilities, lack of qualifications and training, hostile cultural beliefs and family responsibilities.