A parallel compact-TVD method for compressible fluid dynamics employing shared and distributed-memory paradigms

A novel multi-block compact-TVD finite difference method for the simulation of compressible flows is presented. The method combines distributed and shared-memory paradigms to take advantage of the configuration of modern supercomputers that host many cores per shared-memory node. In our approach a domain decomposition technique is applied to a compact scheme using explicit flux formulas at block interfaces. This method offers great improvement in performance over earlier parallel compact methods that rely on the parallel solution of a linear system. A test case is presented to assess the accuracy and parallel performance of the new method

An Introduction to Model Rocketry for the Classroom Teacher

The writer of this project was in a fifth grade teaching position beginning Fall, 1974, in Lacey, Washington. The writer taught thirty students in a self-contained classroom situation. The purpose of this individualized study was to develop a general framework and assemble some specific materials which would aid others in starting and developing a program in model rocketry in an orderly and logical manner

New England funding reference guide

As stated in the thesis project, "This project will produce a reference book (the "Guide") that catalogues all available financing programs offered by various New England based public and quasi-public benefit corporations for small business people, women and people of color (the "Project Focus Group"). The Guide will present the information in a format deemed accessible and convenient by members of the Project Focus Group. Over the course of the last 25 years, various governmental entities and corporations have created numerous financing programs for small business people, women and people of color. In most instances, the programs disburse a significantly lower level of funds than are "allocated" to the program. In other words, the programs are under used. Members of the Project Focus Group could benefit from these programs; however, individuals often find it difficult to obtain sufficient information about particular programs' applicability to their specific financing needs. If no means is found within the next three years to increase awareness among the Project Focus Group of various financing programs offered by various New England based public and quasi-public benefit corporations, these financing programs will remain under used by the Project Focus Group, increasing the risk that the "allocated" funds might be diverted to other uses further shrinking the pool of capital available to the Project Focus Group. The Guide will increase awareness among members of the Project Focus Group of the various financing program available to members of the Project Focus Group. (see Appendix I) The Guide will be printed and available by April 15, 1994." (Library derived description)Reese, T. D. (1993). New England funding reference guide. Retrieved from http://academicarchive.snhu.eduMaster of Science (M.S.)School of Community Economic Developmen

Groundwater, economic, and legal analysis of a proposed diversion from the San Agustin Basin of New Mexico

A private corporation has proposed to export up to 54,000 acre-feet per year of groundwater from the San Agustin basin of central New Mexico for use within the Rio Grande basin. This water would be used for eleven stated purposes. Concerns have been expressed regarding the hydrologic, economic, environmental, and legal consequences. Sustainability of the water supply is an issue, as are effects on the neighboring Rio Grande and Gila River watersheds. A system dynamics model of groundwater and its relationship to the local economy in the basin was developed to explore some of these issues. Subsurface flow between six subbasins was modeled as well as flow to two neighboring groundwater basins. Simulation runs occur on an annual time-step over a 40-year period. Two simulations are presented: 1) no-development based on historic precipitation and evapotranspiration, and 2) development, which includes a 54,000 acre-foot per year appropriation. Model results indicate that effects are measurable. Pumping is sustainable over 40 years. Basin-wide groundwater resources decline 1.76%. Water levels decline 11 feet. Twenty-eight active wells are projected to become dry. Water volume decreases 4.78% or 46 feet in the subbasin where the proposed wells would be located. Water table decreases are averaged for each of six subbasins; wells closer to the pumping center are impacted more than distant wells. Subsurface discharge to the Gila River and Alamosa Creek watersheds decreases 2.93% and 30.2%, respectively. Sensitivity analyses were conducted using hydrologic values suggested in other studies, viz. recharge, hydraulic conductivity, volume, climate change, and water price figures. Basin-wide groundwater volume decreases 1.56-3.87%. Water levels decline 10.6-24.7 feet. Water volume decreases 4.02-10.35%, or 38.8-100 feet in the subbasin where the wells would be located. Subsurface discharge to the Alamosa and Gila River watersheds decreases 21.7-73.7% and 1.67-7.86%, respectively. Examples of costs include drilling 37 wells and constructing associated pipeline, deepening existing wells, and impacts on endangered species. Net costs over 40 years to basin residents and endangered species are projected to be $587,156 and$12.4 million, respectively, the latter assuming water decreases are not offset or replaced. Economic benefits would come primarily through marketing water outside of the basin. Net earnings from water sales range from $1.43 billion to$1.88 billion before taxes. Legal analysis utilizes groundwater and economic results. As New Mexico Office of the State Engineer Application No. RG-89943 is currently being appealed, any future application may need greater specificity, as well as firmly show proof of demand, contractual arrangements, and an absence of harm to basin residents

A preliminary characterization of applied-field MPD thruster plumes

Electric probes, quantitative imaging, and emission spectroscopy were used to study the plume characteristics of applied field magnetohydrodynamic thrusters. The measurements showed that the applied magnetic field plays the dominant role in establishing the plume structure, followed in importance by the cathode geometry and propellant. The anode radius had no measurable impact on the plume characteristics. For all cases studied the plume was highly ionized, though spectral lines of neutral species were always present. Centerline electron densities and temperatures ranged from 2 times 10 (exp 18) to 8 times 10 (exp 18) m(exp -3) and from 7500 to 20,000 K, respectively. The plume was strongly confined by the magnetic field, with radial density gradients increasing monotonically with applied field strength. Plasma potential measurements show a strong effect of the magnetic field on the electrical conductivity and indicate the presence of radial current conduction in the plume

Census Basics and Obtaining Stats from data.census.gov

Designed for first-time conference attendees or as a refresher, this session will cover important census concepts such as race versus ethnicity, large and small geographies, how and when data are released, and key terminology. Examples will be shown using the Census Bureau’s new data portal

Conserving Energy, Conserving Buildings: Airtightness Testing in Historic New England Homes

As a location of early European settlement, New England enjoys a wealth of historic buildings, which represent a rich cultural heritage and insight into New England life. Their longevity also offers the opportunity to identify the characteristics of long-lasting buildings, and to guide design for the historic buildings of the future. Old buildings are inherently sustainable; both because of abstract ideas like “embodied energy” but also by sustaining history and culture over time. This study combines field methods from vernacular architecture (a branch of material culture studies) and building science (which exists between architecture and engineering) to conduct detailed investigations buildings representing four centuries of New England residential construction. Methods include detailed physical measurements of each building, interior and exterior photography, as well as air leakage measurement with a blower door. Buildings are contextualized from the historical literature, and scientific measurements are compared to the literature of both contemporary and other past buildings. Applying these methods to everyday buildings reconnects the study of building performance to its material, technical and cultural context, as well as the behavior of the occupants whose shelter and comfort it is meant to provide. At the same time, the information about the environment created by the building adds depth and nuance to the understanding of the cultural attitudes and activities of generations of occupants and supports the continued stewardship of these shared cultural resources. This research enriches the narrative of historic human and building interaction: infusing scientific questions of how buildings work with the cultural context and human intentions that dictate why. Understanding and preserving old buildings includes environmental as well as cultural conservation, prompts us to think of reversible interventions, and militates against the hubris of present thinking that assumes current knowledge and approaches are optimal, and therefore eternal

Effects of rarefaction on cavity flow in the slip regime

The Navier-Stokes-Fourier equations, with boundary conditions that account for the effects of velocity-slip and temperature-jump, are compared to the direct simulation Monte Carlo method for the case of a lid-driven micro-cavity. Results are presented for Knudsen numbers within the slip-flow regime where the onset of nonequilibrium effects are usually observed. Good agreement is found in predicting the general features of the velocity field and the recirculating flow. However, although the steady-state pressure distributions along the walls of the driven cavity are generally in good agreement with the Monte Carlo data, there is some indication that the results are starting to show noticeable differences, particularly at the separation and reattachment points. The modified Navier-Stokes-Fourier equations consistently overpredict the maximum and minimum pressure values throughout the slip regime. This highlights the need for alternative boundary formulations or modeling techniques that can provide accurate and computationally economic solutions over a wider range of Knudsen numbers