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Technical Paper

A New Approach of Generating Travel Demands for Smart Transportation Systems Modeling

2020-04-14
2020-01-1047
The transportation sector is facing three revolutions: shared mobility, electrification, and autonomous driving. To inform decision making and guide smart transportation system development at the city-level, it is critical to model and evaluate how travelers will behave in these systems. Two key components in such models are (1) individual travel demands with high spatial and temporal resolutions, and (2) travelers’ sociodemographic information and trip purposes. These components impact one’s acceptance of autonomous vehicles, adoption of electric vehicles, and participation in shared mobility. Existing methods of travel demand generation either lack travelers’ demographics and trip purposes, or only generate trips at a zonal level. Higher resolution demand and sociodemographic data can enable analysis of trips’ shareability for car sharing and ride pooling and evaluation of electric vehicles’ charging needs.
Technical Paper

Balloon Launched UAV with Nested Wing for Near Space Applications

2007-09-17
2007-01-3910
There has always been, from the very first UAV, a need for providing cost-effective methods of deploying unmanned aircraft systems at high altitudes. Missions for UAVs at high altitudes are used to conduct atmospheric research, perform global mapping missions, collect remote sensing data, and establish long range communications networks. The team of Gevers Aircraft, Technology Management Group, and Purdue University have designed an innovative balloon launched UAV for these near space applications. A UAV (Payload Return Vehicle) with a nested morphing wing was designed in order to meet the challenges of high altitude flight, and long range and endurance without the need for descent rate control with rockets or a feathering mode.
Technical Paper

Model-based Development for Event-driven Applications using MATLAB: Audio Playback Case Study

2007-04-16
2007-01-0783
Audio playbacks are mechanisms which read data from a storage medium and produce commands and signals which an audio system turns into music. Playbacks are constantly changed to meet market demands, requiring that the control software be updated quickly and efficiently. This paper reviews a 12 month project using the MATLAB/Simulink/Stateflow environment for model-based development, system simulation, autocode generation, and hardware-in-the-loop (HIL) verification for playbacks which read music CDs or MP3 disks. Our team began with a “clean slate” approach to playback architecture, and demonstrated working units running production-ready code. This modular, layered architecture enables rapid development and verification of new playback mechanisms, thereby reducing the time needed to evaluate playback mechanisms and integrate into a complete infotainment system.
Technical Paper

Adoption Patterns for Precision Agriculture

1998-09-14
982041
Early experience with precision farming technology suggests that some hardware and software may follow a rapid S curve adoption path, but that the use of integrated precision farming systems may take longer to develop and be subject to false starts and periods of stagnation. Yield monitors appear to be following a classic S curve adoption path. Precision farming adoption is like that of hybrid corn because changes in organizations will be required to use it effectively. It is like motorized mechanization because it is coming on the market in an immature form and lends itself to farmer tinkering.
Technical Paper

A Status Report of NASA's On-line Project Information System (OPIS), a Tool for Analysis-Focused Data

2008-06-29
2008-01-2019
The On-line Project Information System (OPIS) is a web-based database developed at NASA Ames Research Center (ARC) to improve information transfer and data availability for Exploration Life Support (ELS) projects. The tool enables users to investigate NASA technology development efforts, connect with knowledgeable experts, and to communicate important information. Within OPIS, Principal Investigators (PI's) post technical, administrative, and project participant information for other users to access through browse and search mechanisms. PI's are given technical data reporting requirements in the form of annual report templates, to assure that the information reported satisfies the most critical data needs of various ELS user groups. OPIS fulfills data and functionality needs of key user groups in the ELS Community through data solicitation, centralization, and distribution. The tool also circumvents data loss with ELS participant turnover.
Technical Paper

Health Monitoring for Condition-Based Maintenance of a HMMWV using an Instrumented Diagnostic Cleat

2009-04-20
2009-01-0806
Operation & support costs for military weapon systems accounted for approximately 3/5th of the $500B Department of Defense budget in 2006. In an effort to ensure readiness and decrease these costs for ground vehicle fleets, health monitoring technologies are being developed for Condition-Based Maintenance of individual vehicles within a fleet. Dynamics-based health monitoring is used in this work because vibrations are a passive source of response data, which are global functions of the mechanical loading and properties of the vehicle. A common way of detecting faults in mechanical equipment, such as the suspension and chassis of a ground vehicle, is to compare measured operational vibrations to a reference (or healthy) signature to detect anomalies.
Technical Paper

Modeling of Nonlinear Elastomeric Mounts. Part 1: Dynamic Testing and Parameter Identification

2001-03-05
2001-01-0042
A methodology for modeling elastomeric mounts as nonlinear lumped parameter models is discussed. A key feature of this methodology is that it integrates dynamic test results under different conditions into the model. The first step is to model the mount as a linear model that is simple but reproduces accurately results from dynamic tests under small excitations. Frequency Response Functions (FRF) enables systematic calculation of the parameters for the model. Under more realistic excitation, the mount exhibits non-linearity, which is investigated in the next step. For nonlinear structures, a simple and intuitive method is to use time-domain force-displacement (F-x) curves. Experiments to obtain the F-x curves involve controlling the displacement excitation and measuring the induced forces. From the F-x curves, stiffness and damping parameters are obtained with an optimization technique.
Technical Paper

ISS ECLS System Analysis Software Tools - An Overview and Assessment

2002-07-15
2002-01-2343
There have been many software programs that have provided simulations for the performance and operation of the Environmental Control and Life Support Subsystems (ECLSS) in the International Space Station (ISS) and in the Space Shuttle. These programs have been applied for purposes in system analysis, flight analysis, and ECLSS studies. Flight and system analysis tasks are deemed important. Therefore, more manpower and resources added for such work is considered beneficial. System analysis covers design and trouble-shooting, the validation of Flight Rules, and the contingency analysis. During the engineering design phase, ECLSS modelers predict the performance and interaction of units in a process train. Simulation results can be useful in estimating equipment sizes and costs. This article has also used two examples to illustrate that many Flight Rules need to be validated using properly selected integrated programs.
Technical Paper

Reactive Carbon from Life Support Wastes for Incinerator Flue Gas Cleanup - System Testing

2002-07-15
2002-01-2401
NASA Ames Research Center and Lawrence Berkeley National lab have completed a three-year joint NRA research project on the use of waste biomass to make a gaseous contaminant removal system. The objective of the research was to produce activated carbon from life support wastes and to use the activated carbon to adsorb and remove incineration flue gas contaminants such as NOx. Inedible biomass waste from food production was the primary waste considered for conversion to activated carbon. Previous research at NASA Ames has demonstrated the adsorption of both NOx and SO2 on activated carbon made from biomass and the subsequent conversion of adsorbed NOx to nitrogen and SO2 to sulfur. This paper presents the results testing the whole process system consisting of making, using, and regenerating activated carbon with relevant feed from an actual incinerator. Factors regarding carbon preparation, adsorption and regeneration are addressed.
Technical Paper

Experimental Results Obtained with a Pilot Scale System to Remove Pollutants from an Incinerator Effluent

2002-07-15
2002-01-2395
Incineration is a promising method for converting biomass and human waste into CO2 and H2O during extended planetary exploration. Unfortunately, it produces NOX and other pollutants. TDA Research has developed a safe and effective process to remove NOX from waste incinerator product gas streams. In our process, NO is catalytically oxidized to NO2, which is then removed with a wet scrubber. In a SBIR Phase II project, TDA designed and constructed a pilot scale system, which will be used with the incinerator at NASA Ames Research Center. In this paper, we present test results obtained with our system, which clearly demonstrate the effectiveness of this approach to NOX control.
Technical Paper

The Application of Acoustic Radiation Modes to Engine Oil Pan Design

2017-06-05
2017-01-1844
In modern engine design, downsizing and reducing weight while still providing an increased amount of power has been a general trend in recent decades. Traditionally, an engine design with superior NVH performance usually comes with a heavier, thus sturdier structure. Therefore, modern engine design requires that NVH be considered in the very early design stage to avoid modifications of engine structure at the last minute, when very few changes can be made. NVH design optimization of engine components has become more practical due to the development of computer software and hardware. However, there is still a need for smarter algorithms to draw a direct relationship between the design and the radiated sound power. At the moment, techniques based on modal acoustic transfer vectors (MATVs) have gained popularity in design optimization for their good performance in sound pressure prediction.
Technical Paper

NASA's On-line Project Information System (OPIS) Attributes and Implementation

2006-07-17
2006-01-2190
The On-line Project Information System (OPIS) is a LAMP-based (Linux, Apache, MySQL, PHP) system being developed at NASA Ames Research Center to improve Agency information transfer and data availability, largely for improvement of system analysis and engineering. The tool will enable users to investigate NASA technology development efforts, connect with experts, and access technology development data. OPIS is currently being developed for NASA's Exploration Life Support (ELS) Project. Within OPIS, NASA ELS Managers assign projects to Principal Investigators (PI), track responsible individuals and institutions, and designate reporting assignments. Each PI populates a “Project Page” with a project overview, team member information, files, citations, and images. PI's may also delegate on-line report viewing and editing privileges to specific team members. Users can browse or search for project and member information.
Technical Paper

NASA Specialized Center of Research and Training in Advance Life Support (ALS/NSCORT) Education and Outreach Program

2005-07-11
2005-01-3107
The ALS/NSCORT Education and Outreach provides an avenue to engage and educate higher education students and K-12 educators/students in the center's investigations of the synergistic concepts and principles required for regenerative life-support in extended-duration space exploration. The following K-12 Education programs will be addressed: 1) Key Learning Community Project provides exposure, mentoring and research opportunities for 9-12th grade students at Key Learning Community This program was expanded in 2004 to include an “Explore Mars” 3-day camp experience for 150 Key students. The overall goal of the collaborative project is to motivate students to pursue careers in science, technology, and engineering; 2) Mission to Mars Program introduces 5th-8th grade students to the complex issues involved with living on Mars, stressing the interdisciplinary fundamentals of science, technology and engineering that underlie Advanced Life Support research.
Technical Paper

Development Approach of the Advanced Life Support On-Line Project Information System

2005-07-11
2005-01-3007
The Advanced Life Support (ALS) Project has accelerated an effort to develop an On-line Project Information System (OPIS) for research and technology development (R&TD) data centralization and sharing. This paper presents the OPIS development strategy and status. OPIS is being built as an application framework consisting of an underlying Linux/Apache/MySQL/PHP (LAMP) stack and supporting class libraries, which provide database abstraction and automatic code generation. This approach simplifies the development and maintenance process. The approach also allows for quick adaptation to serve multiple Programs/Projects, although initial deployment is for an ALS module. Data will be located on a secure server at NASA Ames Research Center (ARC). Initial functionality of OPIS will involve a Web-based solicitation of project and technology data, directly from ALS Principal Investigators (PIs) through data collection forms.
Technical Paper

Urine Processing for Water Recovery via Freeze Concentration

2005-07-11
2005-01-3032
Resource recovery, including that of urine water extraction, is one of the most crucial aspects of long-term life support in interplanetary space travel. This paper will consequently examine an innovative approach to processing raw, undiluted urine based on low-temperature freezing. This strategy is uniquely different from NASA's current emphasis on either ‘integrated’ (co-treatment of mixed urine, grey, and condensate waters) or ‘high-temperature’ (i.e., VCD [vapor compression distillation] or VPCAR [vapor phase catalytic ammonia removal]) processing strategies, whereby this liquid freeze-thaw (LiFT) procedure would avoid both chemical and microbial cross-contamination concerns while at the same time securing highly desirable reductions in likely ESM levels.
Technical Paper

Loading Balance and Influent pH in a Solids Thermophilic Aerobic Reactor

2005-07-11
2005-01-2982
The application of biological treatment to solid waste is very promising to facilitate recycling of water, carbon, and nutrients and to reduce the resupply needs of long-term crewed space missions. Degradation of biodegradable solid wastes generated during such a mission is under investigation as part of the NASA Center of Research and Training (NSCORT) at Purdue University. Processing in the solids thermophilic aerobic reactor (STAR) involves the use of high temperature micro-aerobic slurry conditions to degrade solid wastes, enabling the recycling of water, carbon, and nutrients for further downstream uses. Related research presently underway includes technical development and optimization of STAR operations as well as a complementary evaluation of post-STAR processing for gas-stream purification, water recovery by condensate purification, and residuals utilization for both mushroom growth media and nutritional support for fish growth.
Technical Paper

Education and Outreach Program Designed for NASA Specialized Center of Research and Training in Advance Life Support (ALS/NSCORT)

2004-07-19
2004-01-2418
The NASA Specialized Center of Research and Training in Advanced Life Support (ALS/NSCORT) Education and Outreach Program is designed to engage audiences through concepts and technologies highlighted in the NSCORT research program. The outreach program is composed of three thrust areas. These areas are technical outreach (graduate education, technology transfer, presentations to industry, etc.), educational outreach (professional development, undergraduate, K-12), and public outreach (museums, state fairs, etc.) Program design of the technical and educational outreach began in January 2003. This paper reports anecdotal data on one ALS/NSCORT outreach program and gives a brief description of the other programs in their pilot stages. Technical and educational outreach programs developed to date include: 1) Summer Fellowship Research Program, 2) Distance Learning Course, 3) Key Learning Community Collaborative Project and 4) Mission to Mars.
Technical Paper

Solids Thermophilic Aerobic Reactor for Solid Waste Management in Advanced Life Support Systems

2004-07-19
2004-01-2467
Solids thermophilic aerobic reactor (STAR) processing of biodegradable solid waste residuals uses high temperature conditions to reduce waste volume, inactivate pathogens, and render products that may enter the recycle system by providing plant substrate, fish food, and mushroom growth medium. The STAR process recovers and enables the reuse of nutrients, water, and carbon. During the time of this study, STAR was operated at a 3% solids loading rate, with an 11-day retention time at a temperature range of 50-55°C. This document presents the following details: a the evolution to date of the STAR reactor b review of reactor operation and analytical methods c a synopsis of the performance results and related discussion, and d a synopsis of future goals relative to this project's associated research roadmap.
Technical Paper

Pump Controlled Steer-by-Wire System

2013-09-24
2013-01-2349
Modern on-road vehicles have been making steady strides when it comes to employing technological advances featuring active safety systems. However, off-highway machines are lagging in this area and are in dire need for modernization. One chassis system that has been receiving much attention in the automotive field is the steering system, where several electric and electrohydraulic steering architectures have been implemented and steer-by-wire technologies are under current research and development activities. On the other hand, off-highway articulated steering vehicles have not adequately evolved to meet the needs of Original Equipment Manufacturers (OEM) as well as their end customers. Present-day hydrostatic steering systems are plagued with poor energy efficiency due to valve throttling losses and are considered passive systems relative to safety, adjustability, and comfort.
Technical Paper

Frequency Conversion Controlled Vapor Recovery System by Temperature and Flow Signals: Model Design and Parameters Optimization

2013-09-24
2013-01-2348
Current gasoline-gas vapor recovery system is incomplete, for it cannot adjust the vapor-liquid ratio automatically due to the change of working temperature. To solve this problem, this paper intends to design a new system and optimize its parameters. In this research, variables control method is used for tests while linear regression is used for data processing. This new system moves proportion valve away and adds a DSP control module, a frequency conversion device, and a temperature sensor. With this research, it is clearly reviewed that the vapor-liquid ratio should remains 1.0 from 0 °C to 20 °C as its working temperature, be changed into 1.1 from 20 °C to 25 °C, be changed into 1.2 from 25 °C to 30 °C, and be changed into 1.3 when the working temperature is above 30 °C.
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