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A nanocomposite coating that in turn extract self-replenishing (or -healing), superlubricious carbon film directly from natural gas or hydrocarbon gas in mechanical systems. The coating deposits on sealing and sliding surfaces reducing friction and wear. The result is a reduction in inefficiency, machine breakdown, and adverse environmental impact.
The present disclosure identifies pathways, mechanisms, systems and methods to confer chemoautotrophic production of carbon-based products of interest, such as sugars, alcohols, chemicals, amino acids, polymers, fatty acids and their derivatives, hydrocarbons, isoprenoids, and intermediates thereof, in organisms such that these organisms efficiently convert inorganic carbon to organic carbon-based products of interest using inorganic energy, such as formate, and in particular the use of organisms for the commercial production of various carbon-based products of interest.
Neural networks (NNs) are known as universal function approximators and can interpolate nonlinear functions between observed data points. However, when the target domain for deployment shifts from the training domain and NNs must extrapolate, the results are notoriously poor. Prior work Martinez et al. (2019) has shown that NN uncertainty estimates can be used to correct binary predictions in shifted domains without retraining the model. We hypothesize that this approach can be extended to correct real-valued time series predictions. As an exemplar, we consider two mechanical systems with nonlinear dynamics. The first system consists of a spring-mass system where the stiffness changes abruptly, and the second is a real experimental system with a frictional joint that is an open challenge for structural dynamicists to model efficiently. Our experiments will test whether 1) NN uncertainty estimates can identify when the input domain has shifted from the training domain and 2) whether the information used to calculate uncertainty estimates can be used to correct the NN’s time series predictions. While the method as proposed did not significantly improve predictions, our results did show potential for modifications that could improve models’ predictions and play a role in structural health monitoring systems that directly impact public safety.
This draft environmental impact statement (EIS) analyzes the impacts related to DOE’s proposed energy conservation standards for manufactured homes. DOE’s proposed energy conservation standards are based on the 2021 International Energy Conservation Code (IECC) and relate to the building thermal envelope; air sealing; installation of insulation; duct sealing; heating, ventilation and air conditioning (HVAC); service hot water systems; mechanical ventilation fan efficacy; and heating and cooling equipment sizing. The draft EIS evaluates DOE’s proposed action (energy conservation standards tiered based the manufacturers retail list price), alternatives to the proposed action (including energy conservation standards tiered based on size of the manufactured home and untiered standards), and a no action alternative. The draft EIS presents analysis of impacts related to (1) energy resources; (2) air resources (including greenhouse gases, climate change, ambient air quality and indoor air quality); (3) health and safety; (4) socioeconomics; and (5) environmental justice.
A mechanical system is provided for maintaining a desired gap between a stator electrode array and a rotor electrode array by employing repelling magnets on the inner surface of the rotor and on movable carts that support azimuthally segmented stator arrays.
Indoor air pollutant concentrations can be higher than those outdoors, putting occupants at risk. These pollutants come from a variety of sources: materials used to build and furnish indoor spaces, retail products and services, and occupants themselves. Ventilation, temperature, and humidity also affect indoor air quality. It is important to consider the documented benefits of healthy indoor environments at any time – not just during a public health crisis – and it is key to consider the indoor air quality where we do business as well as at home. Small businesses vary in size, services, products, ownership style, and building mechanical systems, yet all benefit from healthy indoor spaces for employees and customers. This guide provides steps, in conjunction with public health guidance, that small businesses can take to improve and maintain indoor air quality. Small businesses often have unique ownership structures – the building owner and business owner can be different parties – so this guide addresses both building and business owner action items. There are many ways to pursue healthy indoor air, including eliminating, minimizing, and/or controlling the contaminants we bring in, and removing or diluting any existing contaminants through ventilation, filtration, air cleaning, and/or disinfection. Best results are achieved through a comprehensive approach combining various strategies, including those discussed in this guide.
Indoor air pollutant concentrations can be higher than those outdoors, putting occupants at risk. These pollutants come from a variety of sources: materials used to build and furnish indoor spaces, retail products and services, and occupants themselves. Ventilation, temperature, and humidity also affect indoor air quality. It is important to consider the documented benefits of healthy indoor environments at any time - not just during a public health crisis - and it is key to consider the indoor air quality where we do business as well as at home. Small businesses vary in size, services, products, ownership style, and building mechanical systems, yet all benefit from healthy indoor spaces for employees and customers. This guide provides steps, in conjunction with public health guidance, that small businesses can take to improve and maintain indoor air quality. Small businesses often have unique ownership structures - the building owner and business owner can be different parties - so this guide addresses both building and business owner action items. There are many ways to pursue healthy indoor air, including eliminating, minimizing, and/or controlling the contaminants we bring in, and removing or diluting any existing contaminants through ventilation, filtration, air cleaning, and/or disinfection. Best results are achieved through a comprehensive approach combining various strategies, including those discussed in this guide.
The present disclosure identifies pathways, mechanisms, systems and methods to confer chemoautotrophic production of carbon-based products of interest, such as sugars, alcohols, chemicals, amino acids, polymers, fatty acids and their derivatives, hydrocarbons, isoprenoids, and intermediates thereof, in organisms such that these organisms efficiently convert inorganic carbon to organic carbon-based products of interest using inorganic energy, such as formate, and in particular the use of organisms for the commercial production of various carbon-based products of interest.
The use of silicone rubber adhesive (particularly, G.E. RTV-108) for sealing large leaks in high vacuum systems subject to mechanical and thermal stresses is shown to be more effective than that of epoxy cements. The sealant is applied externally to the leak while the system is partially evacuated so that it is drawn into the hole.
The mechanisms of void formation during the cooldown and freezing of lithium coolant within the primary loop of SP-100 type systems are investigated. These mechanisms are: (a) homogeneous nucleation, (b) heterogeneous nucleation, (c) normal segregation of helium gas dissolved in liquid lithium, and (d) shrinkage of lithium during freezing. To evaluate the void formation potential due to segregation, a numerical scheme that couples the freezing and mass diffusion processes in both the solid and liquid regions is developed. The results indicated that the formation of He bubbles is unlikely by either homogeneous or heterogeneous nucleation during the cooldown process. However, homogeneous nucleation of He bubbles following the segregation of dissolved He in liquid Lithium ahead of the solid-liquid interface is likely to occur. Results also show that total volume of He void is insignificant when compared to that of shrinkage voids.
Small water resource recovery facilities (WRRFs) serving communities with populations of less than 10,000 people account for 70% of centralized wastewater treatment systems in the United States. Here, with growing interest globally in improving the sustainability of these systems, this study evaluated the environmental life cycle impact and land use tradeoffs of different lagoon and mechanical WRRFs across the diverse climate of Nebraska. Life cycle inventory including construction and operations was collected for 35 existing systems representing a range of commonly used mechanical WRRFs: oxidation ditch, extended aeration, and sequencing batch reactors, and lagoon treatment systems: complete retention, irrigation, and controlled discharge lagoons.
Quality inspection of parts is a major component to any project that requires hardware implementation. Keeping track of all of the inspection jobs is essential to having a smooth running process. By using HTML, the programming language ColdFusion, and the MySQL database, I created a web-based job management system for the 170 Mechanical Inspection Group that will replace the Microsoft Access based management system. This will improve the ways inspectors and the people awaiting inspection view and keep track of hardware as it is in the inspection process. In the end, the management system should be able to insert jobs into a queue, place jobs in and out of a bonded state, pre-release bonded jobs, and close out inspection jobs.
The purpose of this document is to provide evidence for assessing the adequacy of parameterized material models for a collection of materials used in a finite element analyses setting. “Adequacy” is relative to the intended use of the material in particular analyses. The intended application of the material models covered within this document is for system level abnormal mechanical solid mechanics analyses. Generally, material model parameterizations should be valid from temperatures of approximately -50 to 70° C, across a range of strain rates, and (depending on details of the parts involved) large deformations. Each material covered in this document is presented in its own chapter with a common format across materials. Model assumptions, limitations, existing validation results, readiness for use with uncertainty quantification, general usage guidance, and failure considerations are all provided along with specific parameterization inputs suitable for the finite element analysis code Sierra/Solid Mechanics.
The development of an expert system for a 'Mechanical Design System' is discussed. Two different implementation approaches are described. One is coded in C, and the other is realized by a software package - 'Exsys.' The first method has the advantage of greater flexibility and quicker responses, while the latter one is easier to develop. This report discusses the feasible ways to establish a real mechanical intelligent design system applying artificial intelligence techniques so that the products designed by this system could best meet the requirements for space assembly.
Corrosion mechanisms in niobium oxygen potassium system
Advances in computer technology which may have an impact on computational mechanics and flight vehicle structures technology were reviewed. The characteristics of supersystems, highly parallel systems, and small systems are summarized. The interrelations of numerical algorithms and software with parallel architectures are discussed. A scenario for future hardware/software environment and engineering analysis systems is presented. Research areas with potential for improving the effectiveness of analysis methods in the new environment are identified.
A computerized testing system to measure fatigue crack growth under thermal-mechanical fatigue conditions is described. Built around a servohydraulic machine, the system is capable of a push-pull test under stress-controlled or strain-controlled conditions in the temperature range of 25 to 1050 C. Temperature and mechanical strain are independently controlled by the closed-loop system to simulate the complex inservice strain-temperature relationship. A d-c electrical potential method is used to measure crack growth rates. The correction procedure of the potential signal to take into account powerline and RF-induced noises and thermal changes is described. It is shown that the potential drop technique can be used for physical mechanism studies and for modelling crack tip processes.
One of the major goals of the Materials Science and Engineering community is to achieve a fundamental understanding of how alloying affects the mechanical properties of structural materials. Titanium (Ti) and its alloys are particularly in demand due to their relatively lightweight, high strength and corrosion resistance. The low-temperature ductility of hexagonal close-packed (hcp) Ti known as α- Ti is linked to twinning. The addition of alloying elements can affect the deformation mechanisms leading to the change in macro-scale mechanical properties. To understand these effects, our objective is to study and quantify the energetics and kinetics of substitutional and interstitial solutes on the deformation mechanisms of hcp alloys.