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The mechanical and vibration responses of 225‐pin, 324‐pin and 396‐pin PBGA (plastic ball grid array) solder joints have been determined in this study. The effects of overload environmental stress factors on the mechanical responses of the solder joints have been determined by bending and twisting experiments. The effects of shipping and functional environmental stress factors on the vibration responses of the solder joints have been determined by out‐of‐plane vibration experiments and a mathematical analysis.

To examine associations by gender between cancer history and major health insurance transitions (gains and losses), and relationships between insurance transitions and access to care.

Longitudinal 2008–2013 Medical Expenditure Panel Survey data were pooled yielding 2,223 cancer survivors and 50,692 individuals with no cancer history ages 18–63 years upon survey entry, with gender-specific sub-analyses. Access-to-care implications of insurance loss or gain were compared by cancer history and gender.

Initially uninsured cancer survivors were significantly more likely to gain insurance coverage than individuals with no cancer history (RR: 1.25; 95% CI: 1.08–1.44). Females in particular were significantly more likely to gain insurance (unmarried RR: 1.16; 95% CI: 1.06–1.28; married RR: 1.09; 95% CI: 1.02–1.16). Significantly higher rates of difficulty accessing needed medical care and prescription medications were reported by those remaining uninsured, those who lost insurance, and women in general. Remaining uninsured, losing insurance, and male gender were associated with lack of a usual source of care.

Additional outreach to disadvantaged populations is needed to improve access to affordable insurance and medical care. Future longitudinal studies should assess whether major Affordable Care Act (ACA) provisions enacted after the 2008–2013 study period (or those of ACA’s replacement) are addressing these important issues.

Loss of health insurance coverage can reduce health care access resulting in poor health outcomes. Cancer survivors may be particularly at risk of insurance coverage gaps due to the long-term chronic disease trajectory. This study is novel in exploring associations between cancer history by gender and health insurance transitions, both gains and losses, in a national non-elderly adult sample.

The attrition rate within post-secondary institutions is unsettling. Due to a number of factors affecting their wellbeing, students are choosing to escape the pressures of higher education, many within their first year. Focusing on literature regarding the student experience, transformational learning, student engagement, and mentorship, this chapter will explore what encourages first-year students to stay and flourish in university. In addition to current literature, primary case study research conducted with a first-year cohort at a small, private university in Atlantic Canada during the 2021–2022 academic year will also be reviewed. While engagement is often treated as a personal issue, it is also a systemic issue, one that institutions would be smart to address through programming and policy development.

Moringa (Moringa oleifera) is a highly nutritious, fast-growing crop that has emerged in Western markets as a “superfood” and as a “smart crop” for income generation potential among small-scale farmers. As such, moringa has been widely promoted by agricultural development practitioners in low-income countries and by emerging businesses aimed at achieving nutritional and social impact. However, the intrinsic nutritional and agronomic strengths of moringa are not enough to warrant its widespread promotion without first evaluating its economic potential to farmers.

A Land Use System (LUS) analysis modeling tool was employed to test the economic performance of two sets of moringa production practices in Kenya. Data were collected during in-depth interviews and field visits with farmers in Meru that supply a local market, and in Shimba Hills that supply an organic export market.

Results suggest that current production practices over an 12-years assessment period generate a Net Present Value (NPV) of US$8,049 [ha-1] in Meru and a negative NPV of US$697 [ha-1] in Shimba Hills; with average daily returns to family labor of these two production systems of roughly 1.6 times and 0.13 times the prevailing local wage rate, respectively. These differences were attributed to a higher farmgate prices and greater yields in Meru. The analysis tool was then used to predict the effects of changes in farming practices, e.g. if farmers in Meru switched to intensive bed cultivation NPV is estimated to increase by ∼650%.

This study demonstrates the importance of examining the economic performance of agricultural production systems intended to increase the benefits to small-scale farmers.

Our study is the first to assess moringa's economic performance within two production systems in Kenya – a local farmers' cooperative in Meru, and a group of farmers contracted by an export company.

This work aims to demonstrate the use of electrochemical chloride extraction (ECE) to remove chloride ions away from the steel rebar in chloride-contaminated mortar and to mitigate the corrosion of the embedded steel.

To simulate salt contamination in concrete, sodium chloride was added at 0.5 per cent by weight of cement in the fresh mortar featuring a water-to-cement ratio of 0.45. The ECE treatments were varied at two electrical current densities (1 and 5 A/m²), using two electrolytes (0.1M NaOH and 0.1M Na₃BO₃ solutions) and for two periods (2 and 4 weeks). The average free chloride concentration in cement mortars before and after ECE treatment was quantified using a customized chloride sensor, whereas the spatial distribution of relevant elements was obtained using energy-dispersive X-ray spectroscopy. The effect of ECE treatment on the electric resistivity of mortar and the corrosion resistance of steel rebar was investigated by electrochemical impedance spectroscopy and potentiodynamic polarization measurements, respectively.

The experimental results reveal that the ECE treatment was effective in removing chlorides and in improving electric resistivity and compressive strength of the mortar, when using the sodium borate solution as the electrolyte. In this case, a 4-week ECE treatment at 1 A/m² decreased the free chloride content in the mortar by 70 per cent, significantly increased the Ca/Si ratio in the mortar near rebar, led to a more refined and less permeable microstructure of the mortar and significantly improved its compressive strength. The ECE treatment was able to halt the chloride-induced corrosion of steel rebar by passivation. A 4-week ECE treatment at 1 A/m² using sodium hydroxide and sodium borate solutions decreased the corrosion rate of rebar by 36 and 34 per cent, respectively.

This electrochemical rehabilitation of steel-reinforced concrete under chloride-contaminated condition is very effective in prolonging its service life.

This research aims to unravel the role of salt contamination and corrosion inhibiting admixtures in the processes of cement hydration and rebar corrosion.

Mortar samples were prepared with NaCl and one of three corrosion inhibitors, sodium nitrite, disodium β‐glycerophosphate, or N,N′‐dimethylethanolamine, admixed. After 28 days curing, all steel‐mortar samples were ponded with 3 percent NaCl solution and electrochemical impedance spectroscopy (EIS) measurements were conducted periodically during the first 48 days. After 60 days of ponding by 3 percent NaCl solution, field‐emission scanning electron microscopy (FESEM) analyses were conducted on the fracture surface of the steel‐mortar sample.

The FESEM results revealed that admixing chlorides and inhibitors in fresh mortar changed the morphology and cement hydration product of hardener mortar at the steel‐mortar interface. The EIS data indicated that all inhibitors increased the polarization resistance of steel, implying reduced corrosion rate of the steel over 48‐day exposures to salt ponding. 0.05 M N,N′‐dimethylethanolamine was the most effective corrosion inhibitor, followed by 0.5 M sodium nitrite; whereas 0.05 M disodium β‐glycerophosphate was a slower and less capable corrosion inhibitor. The admixing of inhibitors in fresh mortar consistently increased the capacitance and decreased the electrical resistance of hardened mortar. The effect of sodium nitrite inhibitor on the resistance of steel mortar interfacial film compensated that of corrosive NaCl by participating to the formation of a protective ferric oxide film.

The results reported shed light on the complex role of admixed salt and corrosion inhibitors in cement hydration and their implications on the durability of steel‐reinforced concrete.

Using matched data from the 1996 to 2004 Current Population Survey (CPS), we examine racial patterns in annual transitions into and out of health insurance coverage. We first decompose racial differences in static health insurance coverage rates into group differences in transition rates into and out of health insurance coverage. The low rate of health insurance coverage among African-Americans is due almost entirely to higher annual rates of losing health insurance than whites. Among the uninsured, African-Americans have similar rates of gaining health insurance in the following year as whites. Estimates from the matched CPS also indicate that the lower rate of health insurance coverage among Asians is almost entirely accounted for by a relatively high rate of losing health insurance. In contrast to these findings, differences in health insurance coverage between Latinos and whites are due to group differences in both the rate of health insurance loss and gain. Using logit regression estimates, we also calculate nonlinear decompositions for the racial gaps in health insurance loss and gain. We find that two main factors are responsible for differences in health insurance loss between working-age whites and minorities: job loss and education level. Higher rates of job loss account for 30 percent of the health insurance gap for African-Americans and Asians, and 16 percent of the health insurance gap for Latinos. Lower levels of education explain roughly 15 percent of the gap for African-Americans and Latinos (Asians' higher levels of education serve to close the gap). Higher rates of welfare and SSI participation among African-Americans also serve to widen the gap in health insurance loss by 8 percent.

The purpose of this study is to compare the prediction models for half-cell potential (HCP) of RCC slabs cathodically protected using pure magnesium anodes and subjected to chloride ingress.The models for HCP using 1,134 data set values based on experimentation are developed and compared using ANFIS, artificial neural network (ANN) and integrated ANN-GA algorithms.

In this study, RCC slabs, 1000 mm × 1000 mm × 100 mm were cast. Five slabs were cast with 3.5% NaCl by weight of cement, and five more were cast without NaCl. The distance of the point under consideration from the anode in the x- and y-axes, temperature, relative humidity and age of the slab in days were the input parameters, while the HCP values with reference to the Standard Calomel Electrode were the output. Experimental values consisting of 80 HCP values per slab per day were collected for 270 days and were averaged for both cases to generate the prediction model.

In this study, the premise and consequent parameters are trained, validated and tested using ANFIS, ANN and by using ANN as fitness function of GA. The MAPE, RMSE and MAE of the ANFIS model were 24.57, 1702.601 and 871.762, respectively. Amongst the ANN algorithms, Levenberg−Marquardt (LM) algorithm outperforms the other methods, with an overall R-value of 0.983. GA with ANN as the objective function proves to be the best means for the development of prediction model.

Based on the original experimental values, the performance of ANFIS, ANN and GA with ANN as objective function provides excellent results.

The purpose of this paper is to make a contribution to understanding the influence of factors such as the water/cement (W/C) ratio and the granular class on the mechanical and physical properties of high-strength concretes (HSCs). In the formulations of HSC, aggregates by their high mass and volume proportion play an important role. When selecting aggregates, it is necessary to know their intrinsic properties. These properties influence the performance of concrete, in particular the quality of the granulate cimentary adhesion.

This experimental study focused on the effect of W/C ratio (0.25, 0.30, 0.35), the effect of replacing a part of cement by silica fume (SF) (8%), the effect of fraction of aggregate on properties of fresh and hardened concrete, the effect of different environment conversation like drinking water and sea water on compressive strength and the study of absorption of water and softening using the mix design method of the University of Sherbrooke combined with the Dreux-Gorisse method which gives good results.

At the end of our work, the examination of the results obtained made it possible to establish the correlations between the formulations studied and the physicomechanical characteristics of the concrete compositions (HSC25, HSC16, HSC8). The results of this study show that the use of three granular classifications (DMAX8, DMAX16 and DMAX25) and three report W/C (0.25, 0.30 and 0.35) in two different conservation environment (drinking water and sea water) give HSCs, HSC25 with an W/C = 0.25 ratio has reached the largest mechanical strength of 90 MPa for different environments of conservation. For selecting aggregates, it is necessary to know their intrinsic properties, these properties influence the strength of concrete. In general, there is a slight decrease in the compressive resistance of the specimens stored in seawater, it can be said that the conservation life has not had effect on the resistance (28 days). The effect of aggressive environment can appear in the long term.

Mixed design and concrete fabrication with a 28-day compressive strength of up to 68 MPa or more of 90 MPa can now be possible used in Jiel (Algeria), and it should no longer be considered to be used only in an experimental domain. Addition of SF in concrete showed good development of strength between 7 and 28 days, depending on the design of the mix.

Concrete containing 8% SF with W/B of 0.25 has higher compressive strength than the other concretes, and concretes with SF are more resistant than concretes without SF, so it is possible to have concrete with a compressive strength of 82 MPa for W/C 0.25 without SF. Like as a result, we can avoid the use of SF to affect the strength of concrete at compressive strength of 68 MPa, and a slump of 21 cm, because the SF is the most expensive ingredient used in the composition of concrete and is therefore very important economically. One of the main factors of production of HSC above 90 MPa is use of aggregate DMAX25, which is stronger with W/B of 0.25 and 0.30.

This mixtures leads to a very dense microstructure and low porosity and produces increased permeability of HSC and is able to resist the penetration of aggressive agents. This combination has a positive effect on the economy of concrete.

The combination of the Dreux-Gorisse method with the Sherbrook method is very beneficial for determining the percentage of aggregates used, and the use of coarse aggregates of Jijel to obtain HSC with 90 MPa and 16 cm of workability.

The research in competitive facility location (CFL) is quite dynamic, both from a problem formulation and an algorithmic point of view. Research direction has changed immensely over the years to address various competitive challenges. This study aims to explore CFL literature to highlight these research trends, important issues and future research opportunities.

This study utilises the Scopus database to search for related CFL models and adopts a five-step systematic approach for the review process. The five steps involve (1) Article Identification and keyword selection, (2) Selection criteria, (3) Literature review, (4) Literature analysis and (5) Research studies.

The paper presents a comprehensive review of CFL modelling efforts from 1981 to 2021 to provide a depth study of the research evolution in this area. The published articles are classified based on multiple characteristics, including the type of problem, type of competition, game-theoretical approaches, customer behaviour, decision space, type of demand, number of facilities, capacity and budget limitations. The review also highlights the popular problem areas and dedicated research in the respective domain. In addition, a second classification is also provided based on solution methods adopted to solve various CFL models and real-world case studies.

The paper covers 40 years of CFL literature from the perspective of the problem area, CFL characteristics and the solution approach. Additionally, it introduces characteristics such as capacity limit and budget constraint for the first time for classification purposes.