Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “CONTRACTION”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

Skeletal muscle fiber type composition and performance during repeated bouts of maximal, concentric contractions

Force output and fatigue and recovery patterns were studied during intermittent short-term exercise. 27 men performed three bouts of 30 maximal unilateral knee extensions on 2 different occasions. Blood flow was maintained or occluded during recovery periods (60 s). Blood flow was restricted by inflating a pneumatic cuff placed around the proximal thigh. Muscle biopsies from vastus lateralis were analyzed for identification of fast twitch (FT) and slow twitch (ST) fibers and relative FT area. Peak torque decreased during each bout of exercise and more when blood flow was restricted during recovery. Initial peak torque (IPT) and average peak torque (APT) decreased over the three exercise bouts. This response was 3 fold greater without than with blood flow during recovery. IPT and APT decreased more in individuals with mainly FT fibers than in those with mainly ST fibers. It is suggested that performance during repeated bouts of maximal concentric contractions differs between individuals with different fiber type composition. Specifically, in high intensity, intermittent exercise with emphasis on anaerobic energy release a high FT composition may not necessarily be advantageous for performance.

Muscle Contraction↗
NASA NTRSDate not supplied

CoCoSim Tutorial: Contract-based Compositional Verification of Simulink Models

This tutorial presents CoCoSim, a verification framework for MATLAB Simulink and Stateflow models. We demonstrate CoCoSim’s architecture, designed to be compatible with Lustre-based verification tools, as well as easily extensible to other candidate backends. We focus on CoCoSim’s powerful compositional verification scheme, which allows for scalable verification through the usage of abstractions of subsystems, express ed in the form of Assume-Guarantee Contracts. We show CoCoSim’s interconnection with NASA’s Formal Requirements Tool (FRET), that enables a seamless transition between authoring and formally verifying requirements for Simulink/Stateflow models. Finally, we discuss work in progress with regards to test case generation options in CoCoSim, demonstrating the generation of MC/DC tests for Simulink artifacts.

Formal Verification↗
DOE OSTI2015

Impact of Different Standard Type A7A Drum Closure-Ring Practices on Gasket Contraction and Bolt Closure Distance– 15621

The Department of Energy, the Savannah River National Laboratory, several manufacturers of specification drums, and the United States Department of Transportation (DOT) are collaborating in the development of a guidance document for DOE contractors and vendors who wish to qualify containers to DOT 7A Type A requirements. Currently, the effort is focused on DOT 7A Type A 208-liter (55-gallons) drums with a standard 12-gauge bolted closure ring. The U.S. requirements, contained in Title 49, Part 178.350 “Specification 7A; general packaging, Type A specifies a competent authority review of the packaging is not required for the transport of (Class 7) radioactive material containing less than Type A quantities of radioactive material. For Type AF drums, a 4 ft. regulatory free drop must be performed, such that the drum “suffers maximum damage.” Although the actual orientation is not defined by the specification, recent studies suggest that maximum damage would result from a shallow angle top impact, where kinetic energy is transferred to the lid, ultimately causing heavy damage to the lid, or even worse, causing the lid to come off. Since each vendor develops closure recommendations/procedures for the drums they manufacture, key parameters applied to drums during closing vary based on vendor. As part of the initial phase of the collaboration, the impact of the closure variants on the ability of the drum to suffer maximum damage is investigated. Specifically, closure testing is performed varying: 1) the amount of torque applied to the closure ring bolt; and, 2) stress relief protocol, including: a) weight of hammer; and, b) orientation that the hammer hits the closure ring. After closure, the amount of drum lid gasket contraction and the distance that the closure bolt moves through the closure ring is measured.

42 ENGINEERING↗
DOE OSTI2012

Energy Savings Performance Contracts (ESPCs)

Energy savings performance contracts (ESPCs) allow Federal agencies to conduct energy projects with limited to no up-front capital costs, minimizing the need for Congressional appropriations.

Energy, Savings, Performance, Contracts↗
DOE OSTI2012

Energy Savings Performance Contract (ESPC) ENABLE Program

The Energy Savings Performance Contract (ESPC) ENABLE program, a new project funding approach, allows small Federal facilities to realize energy and water savings in six months or less. ESPC ENABLE provides a standardized and streamlined process to install targeted energy conservation measures (ECMs) such as lighting, water, and controls with measurement and verification (M&V) appropriate for the size and scope of the project. This allows Federal facilities smaller than 200,000 square feet to make progress towards important energy efficiency and water conservation requirements.

Energy, Savings, Performance, Contract, ESPC, ENAB↗
DOE OSTI2017

DOE Zero Energy Ready Home Case Study: Greenhill Contracting, Inc., Hickory Ridge

Greenhill Contracting built this 3,912-ft2 house in Gardiner, New York, to the high-performance criteria of the DOE Zero Energy Ready Home (ZERH) program. A highly efficient air-source heat pump heats and cools the home’s interior, while the roof-mounted photovoltaic system offsets electricity usage to cut energy bills to nearly zero. Many months the home owners see a credit on their utility bill.

2017 Housing Innovation Award↗
DOE OSTI2019

Energy Savings Performance Contract Energy Sales Agreements

An energy savings performance contract energy sales agreement (ESPC ESA) is a project structure, similar to a power purchase agreement, that uses the multiyear ESPC authority to implement renewable energy projects (referred to as ESA energy conservation measures [ECMs]) on federal buildings or land. The ESA ECM is initially privately owned for tax-incentive purposes, and the federal agency purchases the electricity it produces. An ESPC ESA is one of the most cost-effective methods for implementing on-site distributed energy projects at civilian federal agency sites.

energy savings performance contract↗