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  1. This paper presents a configurable binary design library including fundamental arithmetic circuits like full-adder, full-subtractor, binary multiplier, shifter, and more. The Chisel Hardware Construction Language (HCL) is employed to build the parameterizable designs with different precision including half-word, word, double-word, and quad-word. Chisel HCL is an open-source embedded domain-specific language that inherits the object-oriented and functional programming aspects of Scala for constructing hardware. Experimental results show the same accuracy achieved by our proposed work compared with the Verilog HDL implementations. The hardware cost in terms of slice count, power consumption, and the maximum clock frequency is further estimated. Compared with traditional design intellectual properties (IPs) provided by IP vendors, our proposed work is configurable and expandable to the other arithmetic implementations and projects. 
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  2. Monitoring and maintaining the air quality in confined spaces have become crucial in recent years due to various reasons. This paper presents the design and implementation of an atmospheric testing device for confined spaces using FPGAs. Specifically, the device connects multiple gas sensors such as oxygen, methane, and nitrogen dioxide to an FPGA architecture that outputs a warning signal to the user in the field. Field usage warnings include a camera for image capturing, a buzzer for audio feedback, an LED for visual feedback, and a display for the gas level in the space. The device also outputs to Matlab for graphing to illustrate the accuracy of the sensors. The project seeks to design, simulate, and implement an expandable device that monitors different gases within a confined space with various safety levels and respective warning systems. 
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  3. In the last few decades, fiber reinforced composites have been established as the materials of choice for lightweight applications in a large spectrum of applications ranging from aerospace, defense, and marine industries to automotive products and consumer goods. With the growing shift to sustainable resources, natural fibers, especially plant fibers, received increased interest throughout the years. Among these natural fibers, silks stand out with low stiffness and a high failure strain, unlike conventional fibers such as carbon or glass. Although gaining traction as a natural alternative reinforcement, silk still has little to no commercial uses despite its higher performance. Besides its higher mechanical properties and lightweight, silk exhibits other attractive properties such as improved flame retardancy and biodegradability. To take advantage of these features, proper fiber/matrix adhesion must be achieved. Such silk/matrix bonding can be inferred from the silk/resin affinity during composite manufacturing. In this study, the affinity/wettability of several silk/resin systems were analyzed via static contact angles using imageJ software to determine candidates for silk reinforced composite laminates with better adhesion. To this end, a combination of four silk fibers and three resin systems were investigated. The investigated silk fibers were Ahimsa, Charmeuse, Habotai, and Tussah; and the resins included a vinyl ester (Hydrex) and two epoxies (INF114 and INR). For Tussah fibers, initial contact angles were consistently one of the lowest. However, these fibers exhibited a higher contact angle over time compared to the other silk fibers studied. Conversely, Ahimsa silk fibers showed the highest initial contact angle, then quickly dropped to com-plete wetting. Habotai fibers dropped towards complete wetting quickly, however, consistently slowed considerably shortly after. Charmeuse fibers performed similarly to Ahimsa fibers with Hydrex, however was considerably slower to wetting with the other resins. Among the investigated resins, Hydrex showed the best affinity to silk fibers with the majority of the lowest initial contact angles and the fastest to complete wetting. INF114 consistently receded at a slower, albeit steady, rate until reaching complete wetting apart from Tussah. INR showed the highest initial contact angles and never reached complete wetting after an hour for two of the four silks investigated. Therefore, the best silk/resin affinity was observed for the Ahimsa and Charmeuse silk fibers and the Hydrex vinyl ester resin. In future work, silk composites with these constituents would be investigated. 
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  4. Thanks to its comparable specific mechanical properties to glass fibers, silk is a natural fiber that can be used as an eco-friendly alternative to synthetic reinforcing fibers in composite materials. Compared to natural fibers, especially plant fibers, silk enjoys higher mechanical performances, lower density, and higher elongation even at low temperatures, silk also exhibits other attractive qualities like flame resistance and being naturally continuous. However, silk is known to be prone to moisture absorption from surrounding humid environments. Moisture absorption may alter the silk/resin dynamics during composite manufacturing, and later lead to prem-ature degradation in the composite thermomechanical properties. This study investigates the effect of humidity on silk/resin wettability using two different resins (one epoxy and one vinyl ester) and three different silk architectures. Silk fibers are first exposed to different relative humidity environments. Subsequently, the affinity of the conditioned silk to a set of resins is assessed through measurements of silk/resin contact angle over time. Different silk/resin systems were observed to have contrasting responses to humidity exposure. While some silk/resin systems, such as Ahimsa/epoxy, did not show any change after humidity exposure. Other combinations showed tremendous susceptibility of silk/resin affinity to prior exposure of silk to humidity. For instance, although starting at virtually the same initial hydrophobic contact angle of ~123 degrees, Habotai silk/epoxy samples had contrasting wetting times. While the dried Habotai silk reached full wetting after around 5 minutes, the silk samples exposed to humidity took around 1 hour to reach full im-pregnation. These findings demonstrate the importance of humidity exposure control in silk reinforced composites. Keywords: Natural-Fiber Composites, Contact Angle, Silk, Wettability, Humidity. 
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  5. Since the mass outbreak of COVID-19 globally, the unique challenges of the pandemic have demanded the global economy, governments, and scientific community adapt in unprecedented ways. Despite pre-existing federal stockpiles of personal protective equipment (PPE) in countries such as the United States, rising shortages and resource constraints have compounded the complexity of curbing the spread of the pandemic and treating patients. To face such shortages, healthcare workers in different parts of the world have been reusing PPE, especially personal protective gloves, and possibly sanitizing them through more cost-effective means such as a simple bleach and water solution. To preserve current and future PPE resources, this study investigates the effect of repeated diluted bleach treatment on mechanical properties of representative gloves to determine if reuse is an acceptable practice. This study aims to determine how bleach sanitization may affect material degradation of gloves when used in working environments. To this end, tensile tests were performed on elastomeric exam gloves with and without bleach sanitization treatments. Control data were prepared for both nonconditioned and humidity conditioned glove samples. Additional glove samples were subjected to ten repetitions of bleach exposure as outlined by Centers for Disease Control and Prevention US (CDC US) guidelines. Subsequently, all glove samples were tensile tested, and mechanical properties were determined. A statistically significant (p ≤ 0.05) loss of stiffness was observed for some of the tested samples, ranging as high as a 90% loss in stiffness. This research could serve to inform medical professionals as to whether sanitization through bleach treatments is acceptable and if so, at how many repetitions this treatment could potentially compromise the glove’s ability to function as intended 
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  6. The human cost of the COVID-19 pandemic has taken a great toll, and led, around the globe, to a shortage in personal protective equipment (PPE) such as medical exam gloves. To face this shortage and keep themselves and patients safe, many front-line healthcare providers have been overextending the life of PPE. Though not ideal, one pragmatic solution often used is the practice of sanitization and extended use of existing PPE. The data produced by these experiments should help determine an acceptable reusability window of PPE in a working environment, by which the effective use time may be extended and justified. The effect of repeated sanitization, using soap and water, on the mechanical performance was investigated for latex and nitrile elastomeric medical exam gloves. Tensile tests were performed for various manufacturer brands commonly used in the United States (Glovepak Europa, Polymed and Sempersure) and India (Surgiglove). Tensile test samples were prepared for each studied glove and treatment combination. Nitrile gloves were observed to be more uniformly affected by the application of soap and water sanitization than latex gloves. Glovepak Europa nitrile gloves saw significant changes (p≤0.001) in elastic modulus after 5, 10 and 20 treatments losing 31.5%, 42.7% and 49.7%, respectively. Sempersure nitrile gloves also saw significant changes (p≤0.05) in elastic modulus at 5, 10 and 20 treatments losing 44.2%, 34.3% and 45.9%, respectively. Surgiglove nitrile gloves saw a significant loss in elastic modulus of 42.0% (p≤0.001) after 10 treatments. Surgiglove powder free latex showed no significant (p>0.05) change after 10 or 20 repeated treatments using soap and water. Polymed powder free latex showed no significant (p>0.05) change after 10 treatments, but did show a significant (p≤0.05) decrease in elastic modulus by 24.2% after 5 treatments and 25.5% after 20 treatments. Surgiglove powdered latex showed a significant (p≤0.05) increase in elastic modulus by 19.9% after 5 treatments and 15.8% after 10 treatments, while showing no significant (p>0.05) change at 20 treatments. Due to the consistent significant degradation after five repetitions, use of soap and water may not be an adequate sanitization procedure for nitrile gloves, since it would potentially induce premature failure. The latex gloves showed no clear pattern and the results were inconclusive. 
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