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The Potential Benefits of Co-Design in Dog-Assisted Treatment Programs for Veterans Seeking Mental Health Care
No full textVeterans are more likely than the general population to experience a range of mental health problems. While many veteran mental health support programs are available, veterans may struggle to access and engage with these services for various reasons (e.g., a stigmatized perception of mental health disorders, mistrust). Animal-assisted services have become more popular in civilian and military health care settings where traditional therapies (e.g., cognitive behavioral therapy) may not always be effective. Assistance dogs, for example, which live with veterans to provide disability support, have been successfully employed for veteran mental health. Unfortunately, a subgroup of veterans may miss out on the benefits of assistance dogs due to an inability or unwillingness to care for a dog full-time. Thus, therapy dogs, which are typically owned by therapists and participate in goal-directed treatment programs, may be a better mental health support option for these veterans. Unfortunately, the process of integrating dogs into mental health treatment for veterans has not been clearly documented in scientific literature. Therefore, it is necessary to design a program that veterans and clinicians would find valuable. Co-design may be useful to find out what veterans need and enable veterans and clinicians to work together to design an effective dog-assisted mental health treatment program. To this end, the aims of this narrative literature review are to highlight the potential effectiveness of dog-assisted treatment for veterans with mental health issues, and to explore why the use of co-design may help with systematic development of a dog-assisted treatment program
The Effect Of Surface Treatment On The Fatigue Strength Of SUS316L Additive Manufactured Products
No full textRotating bending fatigue tests were conducted to investigate the effect of shot peening and barrel finishing on fatigue properties of SUS316L made by laser PBF which was one of additive manufacturing processes. Surface roughness, residual stress, and fatigue strength were investigated for each specimen. As a result, the fatigue strength of the barrel finished specimens was almost same or better than that of the shot peened specimens. Barrel finished specimens increased 4.1 times higher fatigue strength than as-built specimens. The surface roughness of the specimens after barrel finishing was reduced by up to 96% compared to the as-built specimens. On the other hand, the surface roughness of the specimens after shot peening was reduced by up to 68% compared to the as-built specimens. The increase in compressive residual stress was almost equal to each specimen. Therefore, shot peening and barrel finishing drastically affects to increase the fatigue strength of additive manufactured material
Fourier Analyses Of Optical Profilometry As An Inferential Measurement For Impact Coverage.
No full textA critical consideration in peening process design is achieving sufficient impact coverage. Conventional methods for assessing coverage rely on manual inspection, which is time-consuming and poorly suited for automated control. In this work, we investigate the use of frequency-domain analysis to quantify surface modification in peened samples using optical profilometry (OP) data. Three-dimensional surface maps of Almen strips were acquired using a high-resolution OP system and analyzed via fast Fourier transform (FFT) to compute spatial power spectral densities (PSDs). PSD maps and radially averaged profiles reveal consistent amplification of harmonic components similar to the nominal particle size, with increasing intensity and frequency shift as a function of impact velocity and coverage. A normalized PSD metric was introduced to highlight frequency bands most affected by peening, and the peak amplification was shown to correlate with process parameters. These results suggest that spectral decomposition of OP measurements offers a rapid, interpretable, and scalable method for characterizing peened surfaces and could support future closed-loop process control in manufacturing environments
Dynamic Flowsheet Modeling Of Shot Peening Processes
No full textProcess flowsheet modeling is used to map and predict performance by integrating sub-models within a system. This paper presents a dynamic flowsheet for shot peening used to track the effects of media characteristics, removal of worn media, and replenishment thereof. Input parameters include media characteristics, media feed rate, velocity (i.e., air pressure), effective impact area (i.e., nozzle setup), and recharge replenishment. The media working mix is described dynamically using tri-modal size and shape characteristics: as-manufactured, conditioned, and worn modes, each having impact-dependent rate coefficients for transition to the next mode, i.e., as-manufactured \u3e conditioned \u3e worn \u3e debris. The flowsheet includes the effect of media shape by linking the curvature to the peening impact stress field
Evaluating The Effectiveness Of Localized Masking To Prevent Changes In Residual Stress When Shot Peening
No full textWhen shot peening components, it is common practice to mask certain localized regions where peening roughness is not desirable. For example, surfaces that have been highly machined such as bearing races or areas of interference-fit may require masking to protect them from the cold working effects of shot peening. Oftentimes shot peening the grip sections of fatigue test coupons can prevent cracking and failures due to fretting fatigue in the grip area but could affect the outcome of the test if applied to the gauge section of the coupons. Thus, maintaining an “as machined” surface roughness is the most common reason for masking an area when shot peening, where no-observable-dimples is the quality standard. In the aerospace industry, masking is also used on thin areas to prevent distortion or changes to the shape of the part. There are several techniques commonly used for masking. For high production parts, permanent masking tools are often made from rubber or abrasion resistant (UHMW) plastics whereas tape is commonly used when a lower quantity of parts is being shot peened. However, the Authors of this paper could not find any specifications in the literature that describe either what a suitable thickness of the tape should be, or how many layers of tape should be used for any given peening intensity and coverage. As common practice today, one “layer” of tape is typically used for lower peening intensities whereas two “layers” are normally used when peening at higher intensities.
The question that this research aims to answer is, even though dimples from peening may not be not apparent, was there some level of compressive stress introduced in taped regions that could change the performance characteristics in presumably “tape-masked” regions? To answer this question, a comprehensive test plan was developed to map residual stresses using the X-ray Diffraction (XRD) in a series of 7050-T651 aluminum alloy coupons that were masked with various tape thickness’ and shot peened using various peening intensities. Regions that were shot peened with and without tape-masking were characterized, as well as transition regions since some modeling efforts predict that tensile residual stresses directly at the transition area could create a stress concentration.
The following paper discusses the results obtained and conclusions derived from this research
Morphological Awareness: An avenue for improving vocabulary, word recognition, spelling and reading comprehension
No full textLearning requires the integration of many skills, with language development being a crucial foundational aspect. Language development across five domains-phonology (the sounds within a language), morphology (word structure/formation), semantics (word meaning), syntax (sentence structure/grammar), and pragmatics (use in varying contexts)-unequivocally supports the acquisition of reading and writing skills. Specifically, morphological knowledge is vital for improving vocabulary, word recognition, spelling and reading comprehension. This practice brief provides an overview of morphological awareness and derived words, provides a rationale for teaching morphological awareness, and instructional strategies supported by science
Ca/Si-dependent size of silica nanoparticles derived from C-S-H at high water to solid ratio
No full textIn recycling and reusing construction waste, carbonation of recycled concrete fine (RCF) has been successfully applied to produce value-added products, such as silica nanoparticles, via the breaking of calcium silicate hydrate (C-S-H) structure and condensation of silicate chains. However, the intricacies of carbonation of RCFs with varying calcium-silicon (C/S) ratios and their implications on the size of generated silica nanoparticles remains unknown. In this work, we developed an optimized carbonation method at high water to solid ratio to fabricate silica nanoparticles from C-S-H with different C/S ratios. The particle size of silica nanoparticles was found to gradually decrease with the increased C/S ratio of C-S-H. Since as C/S ratio increased, silicate in Q3 state shifted to Q1 state and the silicate chain became shorter, shifting from long-range, disordered to short-range, ordered. As the disordered self-seeding growth of long silicate chains derived from C-S-H continued, the Si-O-Si network of silica nanoparticles became chaotic, leaving more unreacted Si-OH on its surface. On the contrary, the short silicate chains displayed higher possibility of condensation, making nanoparticles with a smaller diameter
Enhancing the reactivity of steel slag for high-quality SCMs
No full textThe transition towards more sustainable steelmaking methods, such as electric arc furnace (EAF) processes, is driving a significant increase in the production of electric arc furnace slag (EAFS). Unlike ground granulated blast furnace slag (GGBFS), a widely used by-product of traditional blast furnace-basic oxygen furnace (BF-BOF) processes, EAFS currently has limited applications, primarily as aggregate in concrete or asphalt, with large volumes landfilled. Efforts to utilise EAFS as a supplementary cementitious material (SCM) have shown mixed outcomes due to its low inherent reactivity and variability in properties. Our research focuses on developing a process to enhance the reactivity of EAFS as an SCM. Additionally, we are exploring variations such as adjusting its chemical composition and blending it with other SCMs to optimise performance. The processed EAFS achieves an amorphous content of 50–95% and promotes the formation of clinker phases, including β-belite, tricalcium aluminate, and, in some cases, alite. Our processing enables the replacement of 20–30 wt. % of ordinary Portland cement (OPC) with minimal strength loss. With targeted adjustments, replacement levels can reach up to 50 wt. %. Compared to GGBFS, our material performs similarly or better, particularly due to its enhanced early reactivity. The softness of processed EAFS also improves grindability, simplifying slag processing. These advancements position EAFS as a transformative SCM, addressing the shortage of high-quality materials, reducing industrial waste, and fostering collaboration between the steel and construction industries. This scalable innovation supports sustainable construction and advances the circular economy
Aqueous Carbonation of Recycled Concrete Fine Dust: Efficiency and Feasibility Analyses
No full textThis study investigates the potential of recycled concrete fine dust (RCD) as a sustainable supplementary cementitious material (SCM) and evaluates its carbonation efficiency through aqueous carbonation. By utilizing RCD, a waste byproduct of concrete demolition, the research aims to enhance the circularity of construction materials while reducing the carbon footprint of cementitious systems. The carbonation process was assessed using X-ray diffraction (XRD) and thermogravimetric analysis (TGA) to identify phase assemblage evolutions and carbonation products. Results reveal that aqueous carbonation significantly enhances the formation of calcium carbonate phases. XRD confirmed the presence of carbonate phases, while TGA provided insights into the degree of carbonation. These findings highlight the benefits of RCD in utilization as a reactive SCM in carbon-negative cement systems
Utilization of FBC ash using a mineral carbonation
No full textThis study evaluates indirect carbonation for CO₂ sequestration and high-purity CaCO3 production using FBC fly ash (HFA) and bottom ash (HBA). NH₄Cl extraction showed higher calcium recovery than DI water, with CaCO3 yields of 10.2 wt.% (HFA) and 8.4 wt.% (HBA). CO2 capture capacities were 45.0 kg and 36.8 kg per ton of ash. Vaterite formation occurred under low pH conditions. Carbonation residues had lower compressive strength but improved durability. This process supports sustainable waste management, circular economy principles, and CCUS by utilizing industrial by-products and generating high-purity CaCO3 for environmental and construction applications