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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.

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At least 55 records · Page 3

Implementing multi-settlement decentralized electricity market design for transactive communities with imperfect communication

Recent advances in information and communication technologies and smart metering, provides strategic opportunities for ``prosumers" to reform their conventional energy practices towards more consumer-centric economies. From an operational perspective, managing power distribution networks is becoming more difficult with such active grid-edge systems providing limited to no visibility or control. Transactive Energy (TE) has been emerging as a key enabler towards effectively and efficiently integrating prosumers into competitive electricity markets. This work presents a transactive implementation of community-centric markets. A co-simulation framework is developed for evaluating the proposed market structure with high-fidelity models. Case studies on the IEEE-123 node test system demonstrate that community-centric transactive markets can enable communities of prosumers to operate collaboratively as grid-edge systems. The potential benefits of implementing community-centric TE systems are also illustrated.

Mukherjee, Monish↗

Elastic Solutions to 2D Plane Strain Problems: Nonlinear Contact and Settlement Analysis for Shallow Foundations

The classical Neumann boundary value problem of an isotropic, homogeneous elastic half-plane under plane strain conditions is readdressed as the limiting case of the fully three-dimensional problem. Analytical solutions of the stress and strain tensors are obtained by taking the limit from known three-dimensional solutions. It is shown that the displacement fields for the plane strain problem are not well defined. A small number of simple expressions are developed, which provide a general solution for linearly-varying traction over arbitrary regions on the boundary. A simple, efficient, and rapidly convergent algorithm is developed which uses these solutions as analytic elements and provides a solution approach to the general boundary value problem. The method is verified against known solutions for Hertzian contact between parallel cylinders. Two numerical examples are presented for the analysis of shallow foundation systems. In the first, the boundary conditions are informed by analytical elastoplastic calculations and a strain influence analysis is performed and compared with the Schmertmann method. Subsequently, empirical laboratory contact traction distributions measured by Bauer et al., in both the normal and tangential directions are employed as boundary conditions for an analysis of the underlying stress field.

42 ENGINEERING↗

Space Settlements: A Design Study

Nineteen professors of engineering, physical science, social science, and architecture, three volunteers, six students, a technical director, and two co-directors worked for ten weeks to construct a convincing picture of how people might permanently sustain life in space on a large scale, and to design a system for the colonization of space. Because the idea of colonizing space has awakened strong public interest, the document presented is written to be understood by the educated public and specialists in other fields. It also includes considerable background material. A table of units and conversion factors is included to aid the reader in interpreting the units of the metric system used in the report.

Richard D Johnson↗

The atmosphere of Mars - Resources for the exploration and settlement of Mars

This paper describes methods of processing the Mars atmosphere to supply water, oxygen and buffer gas for a Mars base. Existing life support system technology is combined with innovative methods of water extraction, and buffer gas processing. The design may also be extended to incorporate an integrated greenhouse to supply food, oxygen and water recycling. It is found that the work required to supply one kilogram of an argon/nitrogen buffer gas is 9.4 kW-hr. To extract water from the dry Martian atmosphere can require up to 102.8 kW-hr per kilogram of water depending on the relative humidity of the air.

Meyer, T. R.↗

Settlement of the moon and ventures beyond

The formation of a permanent base on the moon following the establishment of the Space Station is proposed. The characteristics of the moon which make it advantageous for exploration and as a base are described. Consideration is given to lunar resources, the solar flare problem, and the cost of developing a moon base.

Keaton, Paul W.↗

The resources of Mars for human settlement

Spacecraft exploration of Marshas shown that the essential resources necessary for life support are present on the Martian surface. The key life-support compounds O2, N2, and H2O are available on Mars. The soil could be used as radiation shielding and could provide many useful industrial and construction materials. Compounds with high chemical energy, such as rocket fuels, can be manufactured in-situ on Mars. Solar power, and possibly wind power, are available and practical on Mars. Preliminary engineering studies indicate that fairly autonomous processes can be designed to extract and stockpile Martian consumables.

Meyer, Thomas R.↗

Options for the human settlement of the moon and Mars

The evolutionary approach to space development is discussed in the framework of three overall strategies encompassing four case studies. The first strategy, human expeditions, places emphasis on highly visible, near-term manned missions to Mars or to one of the two moons of Mars. These expeditions are similar in scope and objectives to the Apollo program, with infrastructure development only conducted to the degree necessary to support one or two short-duration trips. Two such expeditionary scenarios, one to Phobus and the other to the Mars surface, are discussed. The second strategy involves the construction of science outposts, and emphasizes scientific exploration as well as investigation of technologies and operations needed for permanent habitation. A third strategy, evolutionary expansion, would explore and settle the inner solar system in a series of steps, with continued development of technologies, experience, and infrastructure.

Fairchild, Kyle O.↗

X-37 and Our Future in Space: Breaking Barriers to Achieve New Milestones in Space Settlement

The X-37 flight demonstrator will serve as a testbed and technology demonstrator for a variety of aerospace technologies needed to produce a successor to the Space Shuttle. Lithium-ion (Li-ion) batteries, thermal protection systems, and hot structures such as flaperons and ruddervators are systems onboard the X-37 which will be of particular use to this effort. This viewgraph presentation identifies stakeholders and participants in the X-37 flight demonstrator program and includes a section of notes which correspond to each of its slides.

Sexton, Jeff↗

Lessons from Popocatepetl Volcano (Mexico): Ancient Settlement Buried by Lavas, Mudflows, and Air-Fall Deposits

Popocatepetl volcano is 5452 m in altitude and capped by glaciers with a long Late Pleistocene-Holocene history. Volcanic activity has been intense during the last 10 000 years. Therefore, the valleys at the NE foothills of the volcano, covered by air-fall ejecta and drained by the runoff of the glaciers, became very attractive to ancient inhabitants of the Xalizintla Valley (XV) west of Puebla City, because of fertility of soils. The XV was occupied by humans about 2000 years ago who witnessed five events related to volcanic activity related to Popo. These events, described in this paper, are being taken into account for volcanic risk evaluation since several towns with a population of more than 23 000 people reoccupied again the Xalizintla Valley.

volcano Popocatepetl Mexico glacier mud flows huma↗

Till the Ductile Anchor Hold: Towards Space Settlements in the 21st Century.

Humans are restless explorers. For 99% of humanity s time on Earth, we have been nomadic wanderers, not farmers, warriors, factory workers, developers, or NASA employees. Only recently--for only a few thousand years--have most humans been tied to the land as many are now. But as more and more of us live in information societies and some indeed in dream societies where our identity derives from the knowledge we share and the image we project, and not from the property we own or the manual work we do, the time may be coming when we should break free from the land, and roam once again. But beware: the reality of Man and Woman the Explorer has a very dark side as well. Many people where I live view the recent experience of Man on the Move as a history of theft, murder, racism, exploitation, and genocide. So we need to be very careful if we say that space exploration is only natural for humans, since the experience has not been very uplifting and noble for most recipients of the exploring of others. But such warnings are not new. Humans have been alerting each other to the dangers of change and novelty from the very beginning: Who and what is this?

Dator, Jim↗

Sensitivity of June Near-Surface Temperatures and Precipitation in the Eastern United States to Historical Land Cover Changes Since European Settlement

Land cover changes alter the near surface weather and climate. Changes in land surface properties such as albedo, roughness length, stomatal resistance, and leaf area index alter the surface energy balance, leading to differences in near surface temperatures. This study utilized a newly developed land cover data set for the eastern United States to examine the influence of historical land cover change on June temperatures and precipitation. The new data set contains representations of the land cover and associated biophysical parameters for 1650, 1850, 1920, and 1992, capturing the clearing of the forest and the expansion of agriculture over the eastern United States from 1650 to the early twentieth century and the subsequent forest regrowth. The data set also includes the inferred distribution of potentially water-saturated soils at each time slice for use in the sensitivity tests. The Regional Atmospheric Modeling System, equipped with the Land Ecosystem-Atmosphere Feedback (LEAF-2) land surface parameterization, was used to simulate the weather of June 1996 using the 1992, 1920, 1850, and 1650 land cover representations. The results suggest that changes in surface roughness and stomatal resistance have caused present-day maximum and minimum temperatures in the eastern United States to warm by about 0.3 C and 0.4 C, respectively, when compared to values in 1650. In contrast, the maximum temperatures have remained about the same, while the minimums have cooled by about 0.1 C when compared to 1920. Little change in precipitation was found.

Strack, John E.↗