Hydronic radiant cooling: Overview and preliminary performance assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feustel, H.E.

1993-05-01

A significant amount of electrical energy used to cool non-residential buildings is drawn by the fans used to transport the cool air through the thermal distribution system. Hydronic systems reduce the amount of air transported through the building by separating ventilation and thermal conditioning. Due to the physical properties of water, hydronic distribution systems can transport a given amount of thermal energy using less than 5% of the otherwise necessary fan energy. This savings alone significantly reduces the energy consumption and especially the peak power requirement This survey clearly shows advantages for radiant cooling in combination with hydronic thermal distributionmore » systems in comparison with the All-Air Systems commonly used in California. The report describes a literature survey on the system's development, thermal comfort issues, and cooling performance. The cooling power potential and the cooling power requirement are investigated for several California climates. Peak-power requirement is compared for hydronic radiant cooling and conventional All-Air-Systems.« less

Millimeter-scale MEMS enabled autonomous systems: system feasibility and mobility

NASA Astrophysics Data System (ADS)

Pulskamp, Jeffrey S.

2012-06-01

Millimeter-scale robotic systems based on highly integrated microelectronics and micro-electromechanical systems (MEMS) could offer unique benefits and attributes for small-scale autonomous systems. This extreme scale for robotics will naturally constrain the realizable system capabilities significantly. This paper assesses the feasibility of developing such systems by defining the fundamental design trade spaces between component design variables and system level performance parameters. This permits the development of mobility enabling component technologies within a system relevant context. Feasible ranges of system mass, required aerodynamic power, available battery power, load supported power, flight endurance, and required leg load bearing capability are presented for millimeter-scale platforms. The analysis illustrates the feasibility of developing both flight capable and ground mobile millimeter-scale autonomous systems while highlighting the significant challenges that must be overcome to realize their potential.

Mass and power modeling of communication satellites

NASA Technical Reports Server (NTRS)

Price, Kent M.; Pidgeon, David; Tsao, Alex

1991-01-01

Analytic estimating relationships for the mass and power requirements for major satellite subsystems are described. The model for each subsystem is keyed to the performance drivers and system requirements that influence their selection and use. Guidelines are also given for choosing among alternative technologies which accounts for other significant variables such as cost, risk, schedule, operations, heritage, and life requirements. These models are intended for application to first order systems analyses, where resources do not warrant detailed development of a communications system scenario. Given this ground rule, the models are simplified to 'smoothed' representation of reality. Therefore, the user is cautioned that cost, schedule, and risk may be significantly impacted where interpolations are sufficiently different from existing hardware as to warrant development of new devices.

Research Perspectives for Material Requirements Planning Systems. Paper No. 434.

ERIC Educational Resources Information Center

Berry, W. L.; Whybark, D. Clay

Material requirements planning (MRP) systems are described as management tools for planning and controlling production operations. A wide variety of industries and production organizations are credited as reporting significant operating improvements in such areas as inventory control, production scheduling, delivery performance, and production…

Software and Human-Machine Interface Development for Environmental Controls Subsystem Support

NASA Technical Reports Server (NTRS)

Dobson, Matthew

2018-01-01

The Space Launch System (SLS) is the next premier launch vehicle for NASA. It is the next stage of manned space exploration from American soil, and will be the platform in which we push further beyond Earth orbit. In preparation of the SLS maiden voyage on Exploration Mission 1 (EM-1), the existing ground support architecture at Kennedy Space Center required significant overhaul and updating. A comprehensive upgrade of controls systems was necessary, including programmable logic controller software, as well as Launch Control Center (LCC) firing room and local launch pad displays for technician use. Environmental control acts as an integral component in these systems, being the foremost system for conditioning the pad and extremely sensitive launch vehicle until T-0. The Environmental Controls Subsystem (ECS) required testing and modification to meet the requirements of the designed system, as well as the human factors requirements of NASA software for Validation and Verification (V&V). This term saw significant strides in the progress and functionality of the human-machine interfaces used at the launch pad, and improved integration with the controller code.

30 CFR 250.803 - Additional production system requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... pressure vessels at any time when there is a change in operating pressures that requires new settings for... significant change in operating pressures. The most recent pressure-recorder charts used to determine... subfreezing climates, the lessee shall furnish evidence to the District Manager that the firefighting system...

30 CFR 250.803 - Additional production system requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... pressure vessels at any time when there is a change in operating pressures that requires new settings for... significant change in operating pressures. The most recent pressure-recorder charts used to determine... subfreezing climates, the lessee shall furnish evidence to the District Manager that the firefighting system...

30 CFR 250.803 - Additional production system requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... pressure vessels at any time when there is a change in operating pressures that requires new settings for... significant change in operating pressures. The most recent pressure-recorder charts used to determine... subfreezing climates, the lessee shall furnish evidence to the District Manager that the firefighting system...

The application of micromachined sensors to manned space systems

NASA Technical Reports Server (NTRS)

Bordano, Aldo; Havey, Gary; Wald, Jerry; Nasr, Hatem

1993-01-01

Micromachined sensors promise significant system advantages to manned space vehicles. Vehicle Health Monitoring (VHM) is a critical need for most future space systems. Micromachined sensors play a significant role in advancing the application of VHM in future space vehicles. This paper addresses the requirements that future VHM systems place on micromachined sensors such as: system integration, performance, size, weight, power, redundancy, reliability and fault tolerance. Current uses of micromachined sensors in commercial, military and space systems are used to document advantages that are gained and lessons learned. Based on these successes, the future use of micromachined sensors in space programs is discussed in terms of future directions and issues that need to be addressed such as how commercial and military sensors can meet future space system requirements.

Energy Efficient Engine: Control system preliminary definition report

NASA Technical Reports Server (NTRS)

Howe, David C.

1986-01-01

The object of the Control Preliminary Definition Program was to define a preliminary control system concept as a part of the Energy Efficient Engine program. The program was limited to a conceptual definition of a full authority digital electronic control system. System requirements were determined and a control system was conceptually defined to these requirements. Areas requiring technological development were identified and a plan was established for implementing the identified technological features, including a control technology demonstration. A significant element of this program was a study of the potential benefits of closed-loop active clearance control, along with laboratory tests of candidate clearance sensor elements for a closed loop system.

Impact of Passive Safety on FHR Instrumentation Systems Design and Classification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holcomb, David Eugene

2015-01-01

Fluoride salt-cooled high-temperature reactors (FHRs) will rely more extensively on passive safety than earlier reactor classes. 10CFR50 Appendix A, General Design Criteria for Nuclear Power Plants, establishes minimum design requirements to provide reasonable assurance of adequate safety. 10CFR50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors, provides guidance on how the safety significance of systems, structures, and components (SSCs) should be reflected in their regulatory treatment. The Nuclear Energy Institute (NEI) has provided 10 CFR 50.69 SSC Categorization Guideline (NEI-00-04) that factors in probabilistic risk assessment (PRA) model insights, as well as deterministic insights, throughmore » an integrated decision-making panel. Employing the PRA to inform deterministic requirements enables an appropriately balanced, technically sound categorization to be established. No FHR currently has an adequate PRA or set of design basis accidents to enable establishing the safety classification of its SSCs. While all SSCs used to comply with the general design criteria (GDCs) will be safety related, the intent is to limit the instrumentation risk significance through effective design and reliance on inherent passive safety characteristics. For example, FHRs have no safety-significant temperature threshold phenomena, thus enabling the primary and reserve reactivity control systems required by GDC 26 to be passively, thermally triggered at temperatures well below those for which core or primary coolant boundary damage would occur. Moreover, the passive thermal triggering of the primary and reserve shutdown systems may relegate the control rod drive motors to the control system, substantially decreasing the amount of safety-significant wiring needed. Similarly, FHR decay heat removal systems are intended to be running continuously to minimize the amount of safety-significant instrumentation needed to initiate operation of systems and components important to safety as required in GDC 20. This paper provides an overview of the design process employed to develop a pre-conceptual FHR instrumentation architecture intended to lower plant capital and operational costs by minimizing reliance on expensive, safety related, safety-significant instrumentation through the use of inherent passive features of FHRs.« less

CrossTalk: The Journal of Defense Software Engineering. Volume 20, Number 7

DTIC Science & Technology

2007-07-01

away from the current Global Command and Control System family of systems, this effort will also require a significant change in both mindset and...which complicate the already significant logistic problems in austere environ- ments. Several efforts are beginning to produce rapidly deployable...currency, and applicability to keep pace with the changing environment and address significant challenges they face. Defense Information Systems Agency

Heat pipes for low-humidity applications

NASA Technical Reports Server (NTRS)

Khattar, Mukesh K.

1989-01-01

A novel application of an air-to-air heat pipe heat exchanger (HPHX) in a cooling and dehumidification process of an air-conditioning system is described which provides significant energy savings in applications requiring reheat of cold supply air to maintain low humidity. The efficiency of the system has been demonstrated in an application requiring a humidity of 40 percent. The use of the HPHX and fine tuning of the air-conditioning system and controls has resulted in significant energy savings. The technology can be advantageously used in many low-humidity applications commonly encountered in high-tech and aerospace facilities.

78 FR 40786 - Self-Regulatory Organizations; NYSE Arca, Inc.; Notice of Filing and Immediate Effectiveness of...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-08

... the level of trading volume sent to the Exchange by such users, such that a user with significant... size of the firm, every user that connects its systems to the Exchange's trading systems requires at... required to support for connectivity to its trading systems. This would also provide incentive for users to...

Identification of high performance and component technology for space electrical power systems for use beyond the year 2000

NASA Technical Reports Server (NTRS)

Maisel, James E.

1988-01-01

Addressed are some of the space electrical power system technologies that should be developed for the U.S. space program to remain competitive in the 21st century. A brief historical overview of some U.S. manned/unmanned spacecraft power systems is discussed to establish the fact that electrical systems are and will continue to become more sophisticated as the power levels appoach those on the ground. Adaptive/Expert power systems that can function in an extraterrestrial environment will be required to take an appropriate action during electrical faults so that the impact is minimal. Manhours can be reduced significantly by relinquishing tedious routine system component maintenance to the adaptive/expert system. By cataloging component signatures over time this system can set a flag for a premature component failure and thus possibly avoid a major fault. High frequency operation is important if the electrical power system mass is to be cut significantly. High power semiconductor or vacuum switching components will be required to meet future power demands. System mass tradeoffs have been investigated in terms of operating at high temperature, efficiency, voltage regulation, and system reliability. High temperature semiconductors will be required. Silicon carbide materials will operate at a temperature around 1000 K and the diamond material up to 1300 K. The driver for elevated temperature operation is that radiator mass is reduced significantly because of inverse temperature to the fourth power.

Propulsion element requirements using electrical power system unscheduled power

NASA Technical Reports Server (NTRS)

Zimmermann, Frank; Hodge, Kathy

1989-01-01

The suitability of using the electrical energy from the Space Station's Electrical Power System (EPS) during the periods of peak solar insolation which is currently not specifically allocated (unscheduled power) to produce propulsion propellants, gaseous hydrogen, and oxygen by electrolyzing water is investigated. Reboost propellant requirements are emphasized, but the results are more generally relevant because the balance of recurring propellant requirements are an order of magnitude smaller and the nonrecurring requirements are not significant on an average basis.

New control design principles based on measured performance and energy analysis of HVAC (Heating, Ventilating, and Air-Conditioning) systems

NASA Astrophysics Data System (ADS)

Hittle, D. C.; Johnson, D. L.

1985-01-01

This report is one of a series on the development of heating, ventilating, and air-conditioning (HVAC) control systems that are simple, efficient, reliable, maintainable, and well-documented. This report identifies major problems associated with three currently used HVAC control systems. It also describes the development of a retrofit control system applicable to military buildings that will allow easy identification of component failures, facilitate repair, and minimize system failures. Evaluation of currently used controls showed that pneumatic temperature control equipment requires a very clean source of supply air and is also not very accurate. Pneumatic, rather than electronic, actuators should be used because they are cheaper and require less maintenance. Thermistor temperature detectors should not be used for HVAC applications because they require frequent calibration. It was found that enthalpy economy cycles cannot be used for control because the humidity sensors required for their use are prone to rapid drift, inaccurate, and hard to calibrate in the field. Performance of control systems greatly affects HVAC operating costs. Significant savings can be achieved if proportional-plus-integral control schemes are used. Use of the retrofit prototype control panel developed in this study on variable-air-volume systems should provide significant energy cost savings, improve comfort and reliability, and reduce maintenance costs.

Software reuse issues affecting AdaNET

NASA Technical Reports Server (NTRS)

Mcbride, John G.

1989-01-01

The AdaNet program is reviewing its long-term goals and strategies. A significant concern is whether current AdaNet plans adequately address the major strategic issues of software reuse technology. The major reuse issues of providing AdaNet services that should be addressed as part of future AdaNet development are identified and reviewed. Before significant development proceeds, a plan should be developed to resolve the aforementioned issues. This plan should also specify a detailed approach to develop AdaNet. A three phased strategy is recommended. The first phase would consist of requirements analysis and produce an AdaNet system requirements specification. It would consider the requirements of AdaNet in terms of mission needs, commercial realities, and administrative policies affecting development, and the experience of AdaNet and other projects promoting the transfer software engineering technology. Specifically, requirements analysis would be performed to better understand the requirements for AdaNet functions. The second phase would provide a detailed design of the system. The AdaNet should be designed with emphasis on the use of existing technology readily available to the AdaNet program. A number of reuse products are available upon which AdaNet could be based. This would significantly reduce the risk and cost of providing an AdaNet system. Once a design was developed, implementation would proceed in the third phase.

Nuclear Thermal Rocket - Arc Jet Integrated System Model

NASA Technical Reports Server (NTRS)

Taylor, Brian D.; Emrich, William

2016-01-01

In the post-shuttle era, space exploration is moving into a new regime. Commercial space flight is in development and is planned to take on much of the low earth orbit space flight missions. With the development of a heavy lift launch vehicle, the Space Launch, System, NASA has become focused on deep space exploration. Exploration into deep space has traditionally been done with robotic probes. More ambitious missions such as manned missions to asteroids and Mars will require significant technology development. Propulsion system performance is tied to the achievability of these missions and the requirements of other developing technologies that will be required. Nuclear thermal propulsion offers a significant improvement over chemical propulsion while still achieving high levels of thrust. Opportunities exist; however, to build upon what would be considered a standard nuclear thermal engine to attain improved performance, thus further enabling deep space missions. This paper discuss the modeling of a nuclear thermal system integrated with an arc jet to further augment performance. The performance predictions and systems impacts are discussed.

48 CFR 2110.7003 - Significant events.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false Significant events. 2110..., AND OTHER PURCHASE DESCRIPTIONS Contract Specifications 2110.7003 Significant events. The contractor is required to inform the contracting officer of all significant events. ...

48 CFR 2110.7003 - Significant events.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Significant events. 2110..., AND OTHER PURCHASE DESCRIPTIONS Contract Specifications 2110.7003 Significant events. The contractor is required to inform the contracting officer of all significant events. ...

48 CFR 2110.7003 - Significant events.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Significant events. 2110..., AND OTHER PURCHASE DESCRIPTIONS Contract Specifications 2110.7003 Significant events. The contractor is required to inform the contracting officer of all significant events. ...

48 CFR 2110.7003 - Significant events.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Significant events. 2110..., AND OTHER PURCHASE DESCRIPTIONS Contract Specifications 2110.7003 Significant events. The contractor is required to inform the contracting officer of all significant events. ...

A complexity science-based framework for global joint operations analysis to support force projection: LDRD Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawton, Craig R.

2015-01-01

The military is undergoing a significant transformation as it modernizes for the information age and adapts to address an emerging asymmetric threat beyond traditional cold war era adversaries. Techniques such as traditional large-scale, joint services war gaming analysis are no longer adequate to support program evaluation activities and mission planning analysis at the enterprise level because the operating environment is evolving too quickly. New analytical capabilities are necessary to address modernization of the Department of Defense (DoD) enterprise. This presents significant opportunity to Sandia in supporting the nation at this transformational enterprise scale. Although Sandia has significant experience with engineeringmore » system of systems (SoS) and Complex Adaptive System of Systems (CASoS), significant fundamental research is required to develop modeling, simulation and analysis capabilities at the enterprise scale. This report documents an enterprise modeling framework which will enable senior level decision makers to better understand their enterprise and required future investments.« less

Arterial intelligent transportation systems : infrastructure elements and traveler information requirements.

DOT National Transportation Integrated Search

2009-08-01

Applying Intelligent Transportation Systems (ITS) to arterial systems allows TxDOT to significantly enhance : transportation system operation efficiency and improve traffic mobility. However, no guidelines are available to : assist TxDOT staff in sel...

The Requirements Generation System: A tool for managing mission requirements

NASA Technical Reports Server (NTRS)

Sheppard, Sylvia B.

1994-01-01

Historically, NASA's cost for developing mission requirements has been a significant part of a mission's budget. Large amounts of time have been allocated in mission schedules for the development and review of requirements by the many groups who are associated with a mission. Additionally, tracing requirements from a current document to a parent document has been time-consuming and costly. The Requirements Generation System (RGS) is a computer-supported cooperative-work tool that assists mission developers in the online creation, review, editing, tracing, and approval of mission requirements as well as in the production of requirements documents. This paper describes the RGS and discusses some lessons learned during its development.

49 CFR 630.4 - Requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... TRANSPORTATION NATIONAL TRANSIT DATABASE § 630.4 Requirements. (a) National Transit Database Reporting System... from the National Transit Database Web site located at http://www.ntdprogram.gov. These reference... Transit Database Web site and a notice of any significant changes to the reporting requirements specified...

49 CFR 630.4 - Requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... TRANSPORTATION NATIONAL TRANSIT DATABASE § 630.4 Requirements. (a) National Transit Database Reporting System... from the National Transit Database Web site located at http://www.ntdprogram.gov. These reference... Transit Database Web site and a notice of any significant changes to the reporting requirements specified...

49 CFR 630.4 - Requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... TRANSPORTATION NATIONAL TRANSIT DATABASE § 630.4 Requirements. (a) National Transit Database Reporting System... from the National Transit Database Web site located at http://www.ntdprogram.gov. These reference... Transit Database Web site and a notice of any significant changes to the reporting requirements specified...

49 CFR 630.4 - Requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... TRANSPORTATION NATIONAL TRANSIT DATABASE § 630.4 Requirements. (a) National Transit Database Reporting System... from the National Transit Database Web site located at http://www.ntdprogram.gov. These reference... Transit Database Web site and a notice of any significant changes to the reporting requirements specified...

49 CFR 630.4 - Requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... TRANSPORTATION NATIONAL TRANSIT DATABASE § 630.4 Requirements. (a) National Transit Database Reporting System... from the National Transit Database Web site located at http://www.ntdprogram.gov. These reference... Transit Database Web site and a notice of any significant changes to the reporting requirements specified...

Software Requirements Analysis as Fault Predictor

NASA Technical Reports Server (NTRS)

Wallace, Dolores

2003-01-01

Waiting until the integration and system test phase to discover errors leads to more costly rework than resolving those same errors earlier in the lifecycle. Costs increase even more significantly once a software system has become operational. WE can assess the quality of system requirements, but do little to correlate this information either to system assurance activities or long-term reliability projections - both of which remain unclear and anecdotal. Extending earlier work on requirements accomplished by the ARM tool, measuring requirements quality information against code complexity and test data for the same system may be used to predict specific software modules containing high impact or deeply embedded faults now escaping in operational systems. Such knowledge would lead to more effective and efficient test programs. It may enable insight into whether a program should be maintained or started over.

A system management methodology for building successful resource management systems

NASA Technical Reports Server (NTRS)

Hornstein, Rhoda Shaller; Willoughby, John K.

1989-01-01

This paper presents a system management methodology for building successful resource management systems that possess lifecycle effectiveness. This methodology is based on an analysis of the traditional practice of Systems Engineering Management as it applies to the development of resource management systems. The analysis produced fifteen significant findings presented as recommended adaptations to the traditional practice of Systems Engineering Management to accommodate system development when the requirements are incomplete, unquantifiable, ambiguous and dynamic. Ten recommended adaptations to achieve operational effectiveness when requirements are incomplete, unquantifiable or ambiguous are presented and discussed. Five recommended adaptations to achieve system extensibility when requirements are dynamic are also presented and discussed. The authors conclude that the recommended adaptations to the traditional practice of Systems Engineering Management should be implemented for future resource management systems and that the technology exists to build these systems extensibly.

Helping System Engineers Bridge the Peaks

NASA Technical Reports Server (NTRS)

Rungta, Neha; Tkachuk, Oksana; Person, Suzette; Biatek, Jason; Whalen, Michael W.; Castle, Joseph; Castle, JosephGundy-Burlet, Karen

2014-01-01

In our experience at NASA, system engineers generally follow the Twin Peaks approach when developing safety-critical systems. However, iterations between the peaks require considerable manual, and in some cases duplicate, effort. A significant part of the manual effort stems from the fact that requirements are written in English natural language rather than a formal notation. In this work, we propose an approach that enables system engineers to leverage formal requirements and automated test generation to streamline iterations, effectively "bridging the peaks". The key to the approach is a formal language notation that a) system engineers are comfortable with, b) is supported by a family of automated V&V tools, and c) is semantically rich enough to describe the requirements of interest. We believe the combination of formalizing requirements and providing tool support to automate the iterations will lead to a more efficient Twin Peaks implementation at NASA.

Mars power system concept definition study. Volume 1: Study results

NASA Technical Reports Server (NTRS)

Littman, Franklin D.

1994-01-01

A preliminary top level study was completed to define power system concepts applicable to Mars surface applications. This effort included definition of power system requirements and selection of power systems with the potential for high commonality. These power systems included dynamic isotope, Proton Exchange Membrane (PEM) regenerative fuel cell, sodium sulfur battery, photovoltaic, and reactor concepts. Design influencing factors were identified. Characterization studies were then done for each concept to determine system performance, size/volume, and mass. Operations studies were done to determine emplacement/deployment maintenance/servicing, and startup/shutdown requirements. Technology development roadmaps were written for each candidate power system (included in Volume 2). Example power system architectures were defined and compared on a mass basis. The dynamic isotope power system and nuclear reactor power system architectures had significantly lower total masses than the photovoltaic system architectures. Integrated development and deployment time phasing plans were completed for an example DIPS and reactor architecture option to determine the development strategies required to meet the mission scenario requirements.

Application of the HARDMAN methodology to the single channel ground-airborne radio system (SINCGARS)

NASA Astrophysics Data System (ADS)

Balcom, J.; Park, J.; Toomer, L.; Feng, T.

1984-12-01

The HARDMAN methodology is designed to assess the human resource requirements early in the weapon system acquisition process. In this case, the methodology was applied to the family of radios known as SINCGARS (Single Channel Ground-Airborne Radio System). At the time of the study, SINCGARS was approaching the Full-Scale Development phase, with 2 contractors in competition. Their proposed systems were compared with a composite baseline comparison (reference) system. The systems' manpower, personnel and training requirements were compared. Based on RAM data, the contractors' MPT figures showed a significant reduction from the figures derived for the baseline comparison system. Differences between the two contractors were relatively small. Impact and some tradeoff analyses were hindered by data access problems. Tactical radios, manpower and personnel requirements analysis, impact and tradeoff analysis, human resource sensitivity, training requirements analysis, human resources in LCSMM, and logistics analyses are discussed.

Joint Optics Structures Experiment (JOSE)

NASA Technical Reports Server (NTRS)

Founds, David

1987-01-01

The objectives of the JOSE program is to develop, demonstrate, and evaluate active vibration suppression techniques for Directed Energy Weapons (DEW). DEW system performance is highly influenced by the line-of-sight (LOS) stability and in some cases by the wave front quality. The missions envisioned for DEW systems by the Strategic Defense Initiative require LOS stability and wave front quality to be significantly improved over any current demonstrated capability. The Active Control of Space Structures (ACOSS) program led to the development of a number of promising structural control techniques. DEW structures are vastly more complex than any structures controlled to date. They will be subject to disturbances with significantly higher magnitudes and wider bandwidths, while holding higher tolerances on allowable motions and deformations. Meeting the performance requirements of the JOSE program requires upgrading the ACOSS techniques to meet new more stringent requirements, the development of requisite sensors and acturators, improved control processors, highly accurate system identification methods, and the integration of hardware and methodologies into a successful demonstration.

Systems Engineering Approach for Conceptual Design of Frigate

DTIC Science & Technology

2015-09-01

ejection area. Topside designers should also take note of the gun maintenance required area (e.g., barrel swabbing area), which requires significant...Figure 9. Range-to-Target Plot (BlueIntercept Missile vs. RedFire) ........................34 Figure 10. Range-to-Target Plot (Main Gun System vs...and the secondary anti-air weapon will be the main gun system. The frigates shall also be equipped with an area terminal type defense (ATTD

Advanced extravehicular activity systems requirements definition study

NASA Technical Reports Server (NTRS)

1988-01-01

A study to define the requirements for advanced extravehicular activities (AEVA) was conducted. The purpose of the study was to develop an understanding of the EVA technology requirements and to map a pathway from existing or developing technologies to an AEVA system capable of supporting long-duration missions on the lunar surface. The parameters of an AEVA system which must sustain the crewmembers and permit productive work for long periods in the lunar environment were examined. A design reference mission (DRM) was formulated and used as a tool to develop and analyze the EVA systems technology aspects. Many operational and infrastructure design issues which have a significant influence on the EVA system are identified.

A Recovery System for Unmanned Underwater Vehicles

DTIC Science & Technology

2017-09-28

300170 1 of 10 A RECOVERY SYSTEM FOR UNMANNED UNDERWATER VEHICLES STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may...6 of 10 forces cannot be easily predicted and can be strong enough to require a significantly larger handling system and significantly more...the sea state, the ship handling system , the capture mechanism and the design of the capture mechanism 400. [0024] The water jets 100 will increase

Naval Systems Engineering Guide

DTIC Science & Technology

2004-10-01

Decision Critical Design Review System Integration Activities IOC FRP Decision Review Production & Deployment Sustainment IOT & FOC Sustainmen...reentered when things change significantly, such as funding, requirements, or schedule. This process must start at the very beginning of a Major...outputs through sub-processes will reveal a number of things : a. Determine the level of process applicability and tailoring required. b. Additional

Defining Medical Capabilities for Exploration Missions

NASA Technical Reports Server (NTRS)

Hailey, M.; Antonsen, E.; Blue, R.; Reyes, D.; Mulcahy, R.; Kerstman, E.; Bayuse, T.

2018-01-01

Exploration-class missions to the moon, Mars and beyond will require a significant change in medical capability from today's low earth orbit centric paradigm. Significant increases in autonomy will be required due to differences in duration, distance and orbital mechanics. Aerospace medicine and systems engineering teams are working together within ExMC to meet these challenges. Identifying exploration medical system needs requires accounting for planned and unplanned medical care as defined in the concept of operations. In 2017, the ExMC Clinicians group identified medical capabilities to feed into the Systems Engineering process, including: determining what and how to address planned and preventive medical care; defining an Accepted Medical Condition List (AMCL) of conditions that may occur and a subset of those that can be treated effectively within the exploration environment; and listing the medical capabilities needed to treat those conditions in the AMCL. This presentation will discuss the team's approach to addressing these issues, as well as how the outputs of the clinical process impact the systems engineering effort.

Requirements to Design to Code: Towards a Fully Formal Approach to Automatic Code Generation

NASA Technical Reports Server (NTRS)

Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.

2004-01-01

A general-purpose method to mechanically transform system requirements into a provably equivalent model has yet to appear. Such a method represents a necessary step toward high-dependability system engineering for numerous possible application domains, including sensor networks and autonomous systems. Currently available tools and methods that start with a formal model of a system and mechanically produce a provably equivalent implementation are valuable but not sufficient. The gap that current tools and methods leave unfilled is that their formal models cannot be proven to be equivalent to the system requirements as originated by the customer. For the classes of systems whose behavior can be described as a finite (but significant) set of scenarios, we offer a method for mechanically transforming requirements (expressed in restricted natural language, or in other appropriate graphical notations) into a provably equivalent formal model that can be used as the basis for code generation and other transformations.

Overall requirements for an advanced underground coal extraction system. [environment effects, miner health and safety, production cost, and coal conservation

NASA Technical Reports Server (NTRS)

Goldsmith, M.; Lavin, M. L.

1980-01-01

Underground mining systems suitable for coal seams expoitable in the year 2000 are examined with particular relevance to the resources of Central Appalachia. Requirements for such systems may be summarized as follows: (1) production cost; (2)miner safety; (3) miner health; (4) environmental impact; and (5) coal conservation. No significant trade offs between production cost and other performance indices were found.

Achieving reutilization of scheduling software through abstraction and generalization

NASA Technical Reports Server (NTRS)

Wilkinson, George J.; Monteleone, Richard A.; Weinstein, Stuart M.; Mohler, Michael G.; Zoch, David R.; Tong, G. Michael

1995-01-01

Reutilization of software is a difficult goal to achieve particularly in complex environments that require advanced software systems. The Request-Oriented Scheduling Engine (ROSE) was developed to create a reusable scheduling system for the diverse scheduling needs of the National Aeronautics and Space Administration (NASA). ROSE is a data-driven scheduler that accepts inputs such as user activities, available resources, timing contraints, and user-defined events, and then produces a conflict-free schedule. To support reutilization, ROSE is designed to be flexible, extensible, and portable. With these design features, applying ROSE to a new scheduling application does not require changing the core scheduling engine, even if the new application requires significantly larger or smaller data sets, customized scheduling algorithms, or software portability. This paper includes a ROSE scheduling system description emphasizing its general-purpose features, reutilization techniques, and tasks for which ROSE reuse provided a low-risk solution with significant cost savings and reduced software development time.

An aspect-oriented approach for designing safety-critical systems

NASA Astrophysics Data System (ADS)

Petrov, Z.; Zaykov, P. G.; Cardoso, J. P.; Coutinho, J. G. F.; Diniz, P. C.; Luk, W.

The development of avionics systems is typically a tedious and cumbersome process. In addition to the required functions, developers must consider various and often conflicting non-functional requirements such as safety, performance, and energy efficiency. Certainly, an integrated approach with a seamless design flow that is capable of requirements modelling and supporting refinement down to an actual implementation in a traceable way, may lead to a significant acceleration of development cycles. This paper presents an aspect-oriented approach supported by a tool chain that deals with functional and non-functional requirements in an integrated manner. It also discusses how the approach can be applied to development of safety-critical systems and provides experimental results.

Global Hawk Systems Engineering. Case Study

DTIC Science & Technology

2010-01-01

Management Core System ( TBMCS ) (complex software development) • F-111 Fighter (joint program with significant involvement by the Office of the...Software Requirements Specification TACC Tailored Airworthiness Certification Criteria TBMCS Theater Battle Management Core System TEMP Test and

A next generation advanced traveler information precursor system (ATIS 2.0 precursor system) system requirements.

DOT National Transportation Integrated Search

2016-12-01

Advanced Traveler Information Systems (ATIS) have experienced significant growth since their initial inception in the 1990s. Technologies have continued to evolve at a rapid pace, enabling the integration of advanced solutions for traveler informatio...

A flexible data fusion architecture for persistent surveillance using ultra-low-power wireless sensor networks

NASA Astrophysics Data System (ADS)

Hanson, Jeffrey A.; McLaughlin, Keith L.; Sereno, Thomas J.

2011-06-01

We have developed a flexible, target-driven, multi-modal, physics-based fusion architecture that efficiently searches sensor detections for targets and rejects clutter while controlling the combinatoric problems that commonly arise in datadriven fusion systems. The informational constraints imposed by long lifetime requirements make systems vulnerable to false alarms. We demonstrate that our data fusion system significantly reduces false alarms while maintaining high sensitivity to threats. In addition, mission goals can vary substantially in terms of targets-of-interest, required characterization, acceptable latency, and false alarm rates. Our fusion architecture provides the flexibility to match these trade-offs with mission requirements unlike many conventional systems that require significant modifications for each new mission. We illustrate our data fusion performance with case studies that span many of the potential mission scenarios including border surveillance, base security, and infrastructure protection. In these studies, we deployed multi-modal sensor nodes - including geophones, magnetometers, accelerometers and PIR sensors - with low-power processing algorithms and low-bandwidth wireless mesh networking to create networks capable of multi-year operation. The results show our data fusion architecture maintains high sensitivities while suppressing most false alarms for a variety of environments and targets.

Candidate Mission from Planet Earth control and data delivery system architecture

NASA Technical Reports Server (NTRS)

Shapiro, Phillip; Weinstein, Frank C.; Hei, Donald J., Jr.; Todd, Jacqueline

1992-01-01

Using a structured, experienced-based approach, Goddard Space Flight Center (GSFC) has assessed the generic functional requirements for a lunar mission control and data delivery (CDD) system. This analysis was based on lunar mission requirements outlined in GSFC-developed user traffic models. The CDD system will facilitate data transportation among user elements, element operations, and user teams by providing functions such as data management, fault isolation, fault correction, and link acquisition. The CDD system for the lunar missions must not only satisfy lunar requirements but also facilitate and provide early development of data system technologies for Mars. Reuse and evolution of existing data systems can help to maximize system reliability and minimize cost. This paper presents a set of existing and currently planned NASA data systems that provide the basic functionality. Reuse of such systems can have an impact on mission design and significantly reduce CDD and other system development costs.

The Future Impact of Wind on BPA Power System Load Following and Regulation Requirements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makarov, Yuri V.; Lu, Shuai; McManus, Bart

Wind power is growing in a very fast pace as an alternative generating resource. As the ratio of wind power over total system capacity increases, the impact of wind on various system aspects becomes significant. This paper presents a methodology to study the future impact of wind on BPA power system load following and regulation requirements. Existing methodologies for similar analysis include dispatch model simulation and standard deviation evaluation on load and wind data. The methodology proposed in this paper uses historical data and stochastic processes to simulate the load balancing processes in the BPA power system. It mimics themore » actual power system operations therefore the results are close to reality yet the study based on this methodology is convenient to perform. The capacity, ramp rate and ramp duration characteristics are extracted from the simulation results. System load following and regulation capacity requirements are calculated accordingly. The ramp rate and ramp duration data obtained from the analysis can be used to evaluate generator response or maneuverability requirement and regulating units’ energy requirement, respectively.« less

The new Langley Research Center advanced real-time simulation (ARTS) system

NASA Technical Reports Server (NTRS)

Crawford, D. J.; Cleveland, J. I., II

1986-01-01

Based on a survey of current local area network technology with special attention paid to high bandwidth and very low transport delay requirements, NASA's Langley Research Center designed a new simulation subsystem using the computer automated measurement and control (CAMAC) network. This required significant modifications to the standard CAMAC system and development of a network switch, a clocking system, new conversion equipment, new consoles, supporting software, etc. This system is referred to as the advanced real-time simulation (ARTS) system. It is presently being built at LaRC. This paper provides a functional and physical description of the hardware and a functional description of the software. The requirements which drove the design are presented as well as present performance figures and status.

MTL distributed magnet measurement system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nogiec, J.M.; Craker, P.A.; Garbarini, J.P.

1993-04-01

The Magnet Test Laboratory (MTL) at the Superconducting Super collider Laboratory will be required to precisely and reliably measure properties of magnets in a production environment. The extensive testing of the superconducting magnets comprises several types of measurements whose main purpose is to evaluate some basic parameters characterizing magnetic, mechanic and cryogenic properties of magnets. The measurement process will produce a significant amount of data which will be subjected to complex analysis. Such massive measurements require a careful design of both the hardware and software of computer systems, having in mind a reliable, maximally automated system. In order to fulfillmore » this requirement a dedicated Distributed Magnet Measurement System (DMMS) is being developed.« less

Precise time technology for selected Air Force systems: Present status and future requirements

NASA Technical Reports Server (NTRS)

Yannoni, N. F.

1981-01-01

Precise time and time interval (PTTI) technology is becoming increasingly significant to Air Force operations as digital techniques find expanded utility in military missions. Timing has a key role in the function as well as in navigation. A survey of the PTTI needs of several Air Force systems is presented. Current technology supporting these needs was reviewed and new requirements are emphasized for systems as they transfer from initial development to final operational deployment.

Requirements to Design to Code: Towards a Fully Formal Approach to Automatic Code Generation

NASA Technical Reports Server (NTRS)

Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.

2005-01-01

A general-purpose method to mechanically transform system requirements into a provably equivalent model has yet to appear. Such a method represents a necessary step toward high-dependability system engineering for numerous possible application domains, including distributed software systems, sensor networks, robot operation, complex scripts for spacecraft integration and testing, and autonomous systems. Currently available tools and methods that start with a formal model of a system and mechanically produce a provably equivalent implementation are valuable but not sufficient. The gap that current tools and methods leave unfilled is that their formal models cannot be proven to be equivalent to the system requirements as originated by the customer. For the classes of systems whose behavior can be described as a finite (but significant) set of scenarios, we offer a method for mechanically transforming requirements (expressed in restricted natural language, or in other appropriate graphical notations) into a provably equivalent formal model that can be used as the basis for code generation and other transformations.

Requirements to Design to Code: Towards a Fully Formal Approach to Automatic Code Generation

NASA Technical Reports Server (NTRS)

Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.

2005-01-01

A general-purpose method to mechanically transform system requirements into a provably equivalent model has yet to appear. Such a method represents a necessary step toward high-dependability system engineering for numerous possible application domains, including distributed software systems, sensor networks, robot operation, complex scripts for spacecraft integration and testing, and autonomous systems. Currently available tools and methods that start with a formal model of a: system and mechanically produce a provably equivalent implementation are valuable but not sufficient. The "gap" that current tools and methods leave unfilled is that their formal models cannot be proven to be equivalent to the system requirements as originated by the customer. For the ciasses of systems whose behavior can be described as a finite (but significant) set of scenarios, we offer a method for mechanically transforming requirements (expressed in restricted natural language, or in other appropriate graphical notations) into a provably equivalent formal model that can be used as the basis for code generation and other transformations.

Electric propulsion for lunar exploration and lunar base development

NASA Technical Reports Server (NTRS)

Palaszewski, Bryan

1992-01-01

Using electric propulsion to deliver materials to lunar orbit for the development and construction of a lunar base was investigated. Because the mass of the base and its life-cycle resupply mass are large, high specific impulse propulsion systems may significantly reduce the transportation system mass and cost. Three electric propulsion technologies (arcjet, ion, and magnetoplasmadynamic (MPD) propulsion) were compared with oxygen/hydrogen propulsion for a lunar base development scenario. Detailed estimates of the orbital transfer vehicles' (OTV's) masses and their propellant masses are presented. The fleet sizes for the chemical and electric propulsion systems are estimated. Ion and MPD propulsion systems enable significant launch mass savings over O2/H2 propulsion. Because of the longer trip time required for the low-thrust OTV's, more of them are required to perform the mission model. By offloading the lunar cargo from the manned O2/H2 OTV missions onto the electric propulsion OTV's, a significant reduction of the low Earth orbit (LEO) launch mass is possible over the 19-year base development period.

Civilian Radioactive Waste Management System Requirements Document

DOE Office of Scientific and Technical Information (OSTI.GOV)

C.A. Kouts

2006-05-10

The CRD addresses the requirements of Department of Energy (DOE) Order 413.3-Change 1, ''Program and Project Management for the Acquisition of Capital Assets'', by providing the Secretarial Acquisition Executive (Level 0) scope baseline and the Program-level (Level 1) technical baseline. The Secretarial Acquisition Executive approves the Office of Civilian Radioactive Waste Management's (OCRWM) critical decisions and changes against the Level 0 baseline; and in turn, the OCRWM Director approves all changes against the Level 1 baseline. This baseline establishes the top-level technical scope of the CRMWS and its three system elements, as described in section 1.3.2. The organizations responsible formore » design, development, and operation of system elements described in this document must therefore prepare subordinate project-level documents that are consistent with the CRD. Changes to requirements will be managed in accordance with established change and configuration control procedures. The CRD establishes requirements for the design, development, and operation of the CRWMS. It specifically addresses the top-level governing laws and regulations (e.g., ''Nuclear Waste Policy Act'' (NWPA), 10 Code of Federal Regulations (CFR) Part 63, 10 CFR Part 71, etc.) along with specific policy, performance requirements, interface requirements, and system architecture. The CRD shall be used as a vehicle to incorporate specific changes in technical scope or performance requirements that may have significant program implications. Such may include changes to the program mission, changes to operational capability, and high visibility stakeholder issues. The CRD uses a systems approach to: (1) identify key functions that the CRWMS must perform, (2) allocate top-level requirements derived from statutory, regulatory, and programmatic sources, and (3) define the basic elements of the system architecture and operational concept. Project-level documents address CRD requirements by further defining system element functions, decomposing requirements into significantly greater detail, and developing designs of system components, facilities, and equipment. The CRD addresses the identification and control of functional, physical, and operational boundaries between and within CRWMS elements. The CRD establishes requirements regarding key interfaces between the CRWMS and elements external to the CRWMS. Project elements define interfaces between CRWMS program elements. The Program has developed a change management process consistent with DOE Order 413.3-Change 1. Changes to the Secretarial Acquisition Executive and Program-level baselines must be approved by a Program Baseline Change Control Board. Specific thresholds have been established for identifying technical, cost, and schedule changes that require approval. The CRWMS continually evaluates system design and operational concepts to optimize performance and/or cost. The Program has developed systems analysis tools to assess potential enhancements to the physical system and to determine the impacts from cost saving initiatives, scientific and technological improvements, and engineering developments. The results of systems analyses, if appropriate, are factored into revisions to the CRD as revised Programmatic Requirements.« less

Complying with US and European complaint handling requirements.

PubMed

Donawa, M E

1997-09-01

The importance of customer complaints for providing valuable information on the use of medical devices is clearly reflected in United States (US) and European quality system requirements for handling complaints. However, there are significant differences in US and European complaint handling requirements. This article will discuss those differences and methods for ensuring compliance.

Earth resources data acquisition sensor study

NASA Technical Reports Server (NTRS)

Grohse, E. W.

1975-01-01

The minimum data collection and data processing requirements are investigated for the development of water monitoring systems, which disregard redundant and irrelevant data and process only those data predictive of the onset of significant pollution events. Two approaches are immediately suggested: (1) adaptation of a presently available ambient air monitoring system developed by TVA, and (2) consideration of an air, water, and radiological monitoring system developed by the Georgia Tech Experiment Station. In order to apply monitoring systems, threshold values and maximum allowable rates of change of critical parameters such as dissolved oxygen and temperature are required.

Non-rocket Earth-Moon transport system

NASA Astrophysics Data System (ADS)

Bolonkin, Alexander

2003-06-01

This paper proposes a new transportation system for travel between Earth and Moon. This transportation system uses mechanical energy transfer and requires only minimal energy, using an engine located on Earth. A cable directly connects a pole of the Earth through a drive station to the lunar surface_ The equation for an optimal equal stress cable for complex gravitational field of Earth-Moon has been derived that allows significantly lower cable masses. The required strength could be provided by cables constructed of carbon nanotubes or carbon whiskers. Some of the constraints on such a system are discussed.

Storage battery aspects of air-electrode research

NASA Astrophysics Data System (ADS)

Buzelli, E. S.; Berk, L. B.; Demczyk, B. G.; Zuckerbrod, D.

The use of air electrodes in secondary, alkaline energy storage systems offers several significant advantages over other conventional cathode systems. The oxygen, required for operation, is not stored or carried within the battery system. The weight of the air electrode is significantly lower than alternative cathode couples for the same mission. The cost of the air electrode is potentially low. As a result of these characteristics, alkaline electrolyte energy storage systems with air electrodes have the potential for achieving energy density levels in excess of 150 Whr/kg at low costs, $30-$40/kWh. The primary key to a successful metal-air secondary battery for an EV application is the development of a bifunctinal air electrode. This paper discusses the various aspects of air electrode research for this application, as well as the physical and performance requirements of the air electrode in this advanced technology battery system.

Storage battery aspects of air-electrode research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buzzelli, E.S.; Berk, L.B.; Demczyk, B.G.

1983-08-01

The use of air electrodes in secondary, alkaline energy storage systems offers several significant advantages over other conventional cathode systems. The oxygen, required for operation, is not stored or carried within the battery system. The weight of the air electrode is significantly lower than alternative cathode couples for the same mission. The cost of the air electrode is potentially low. As a result of these characteristics, alkaline electrolyte energy storage systems with air electrodes have the potential for achieving energy density levels in excess of 150 Whr/kg at low costs, $30-$40/kWh. The primary key to a successful metal-air secondary batterymore » for an EV application is the development of a bifunctional air electrode. This paper discusses the various aspects of air electrode research for this application, as well as the physical and performance requirements of the air electrode in this advanced technology battery system.« less

Variable Structure PID Control to Prevent Integrator Windup

NASA Technical Reports Server (NTRS)

Hall, C. E.; Hodel, A. S.; Hung, J. Y.

1999-01-01

PID controllers are frequently used to control systems requiring zero steady-state error while maintaining requirements for settling time and robustness (gain/phase margins). PID controllers suffer significant loss of performance due to short-term integrator wind-up when used in systems with actuator saturation. We examine several existing and proposed methods for the prevention of integrator wind-up in both continuous and discrete time implementations.

Designing the microturbine engine for waste-derived fuels.

PubMed

Seljak, Tine; Katrašnik, Tomaž

2016-01-01

Presented paper deals with adaptation procedure of a microturbine (MGT) for exploitation of refuse derived fuels (RDF). RDF often possess significantly different properties than conventional fuels and usually require at least some adaptations of internal combustion systems to obtain full functionality. With the methodology, developed in the paper it is possible to evaluate the extent of required adaptations by performing a thorough analysis of fuel combustion properties in a dedicated experimental rig suitable for testing of wide-variety of waste and biomass derived fuels. In the first part key turbine components are analyzed followed by cause and effect analysis of interaction between different fuel properties and design parameters of the components. The data are then used to build a dedicated test system where two fuels with diametric physical and chemical properties are tested - liquefied biomass waste (LW) and waste tire pyrolysis oil (TPO). The analysis suggests that exploitation of LW requires higher complexity of target MGT system as stable combustion can be achieved only with regenerative thermodynamic cycle, high fuel preheat temperatures and optimized fuel injection nozzle. Contrary, TPO requires less complex MGT design and sufficient operational stability is achieved already with simple cycle MGT and conventional fuel system. The presented approach of testing can significantly reduce the extent and cost of required adaptations of commercial system as pre-selection procedure of suitable MGT is done in developed test system. The obtained data can at the same time serve as an input for fine-tuning the processes for RDF production. Copyright © 2015. Published by Elsevier Ltd.

A low cost LST pointing control system

NASA Technical Reports Server (NTRS)

Glaese, J. R.; Kennel, H. F.; Nurre, G. S.; Seltzer, S. M.; Shelton, H. L.

1975-01-01

Vigorous efforts to reduce costs, coupled with changes in LST guidelines, took place in the Fall of 1974. These events made a new design of the LST and its Pointing and Attitude Control System possible. The major design changes are summarized as: an annular Support Systems Module; removal of image motion compensation; reaction wheels instead of CMG's; a magnetic torquer system to also perform the emergency and backup functions, eliminating the previously required mass expulsion system. Preliminary analysis indicates the Low Cost LST concept can meet the newly defined requirements and results in a significantly reduced development cost.

Approach to developing reliable space reactor power systems

NASA Technical Reports Server (NTRS)

Mondt, Jack F.; Shinbrot, Charles H.

1991-01-01

During Phase II, the Engineering Development Phase, the SP-100 Project has defined and is pursuing a new approach to developing reliable power systems. The approach to developing such a system during the early technology phase is described along with some preliminary examples to help explain the approach. Developing reliable components to meet space reactor power system requirements is based on a top-down systems approach which includes a point design based on a detailed technical specification of a 100-kW power system. The SP-100 system requirements implicitly recognize the challenge of achieving a high system reliability for a ten-year lifetime, while at the same time using technologies that require very significant development efforts. A low-cost method for assessing reliability, based on an understanding of fundamental failure mechanisms and design margins for specific failure mechanisms, is being developed as part of the SP-100 Program.

Mach 6.5 air induction system design for the Beta 2 two-stage-to-orbit booster vehicle

NASA Technical Reports Server (NTRS)

Midea, Anthony C.

1991-01-01

A preliminary, two-dimensional, mixed compression air induction system is designed for the Beta II Two Stage to Orbit booster vehicle to minimize installation losses and efficiently deliver the required airflow. Design concepts, such as an external isentropic compression ramp and a bypass system were developed and evaluated for performance benefits. The design was optimized by maximizing installed propulsion/vehicle system performance. The resulting system design operating characteristics and performance are presented. The air induction system design has significantly lower transonic drag than similar designs and only requires about 1/3 of the bleed extraction. In addition, the design efficiently provides the integrated system required airflow, while maintaining adequate levels of total pressure recovery. The excellent performance of this highly integrated air induction system is essential for the successful completion of the Beta II booster vehicle mission.

Evaluation of in-situ thermal energy storage for lunar based solar dynamic systems

NASA Technical Reports Server (NTRS)

Crane, Roger A.

1991-01-01

A practical lunar based thermal energy storage system, based on locally available materials, could significantly reduce transportation requirements and associated costs of a continuous, solar derived power system. The concept reported here is based on a unique, in-situ approach to thermal energy storage. The proposed design is examined to assess the problems of start-up and the requirements for attainment of stable operation. The design remains, at this stage, partially conceptional in nature, but certain aspects of the design, bearing directly on feasibility, are examined in some detail. Specifically included is an engineering evaluation of the projected thermal performance of this system. Both steady state and start-up power requirements are evaluated and the associated thermal losses are evaluated as a basis for establishing potential system performance.

A Systemic Integration of Technology for New-Paradigm Education

ERIC Educational Resources Information Center

Watson, William R.; Watson, Sunnie Lee; Reigeluth, Charles M.

2012-01-01

Educational reform efforts have failed to create widespread improvement. The authors argue that rather than trying to improve the existing system of education, a new learner-centered paradigm is needed that supports individualized learning. Such a significantly different system of education will require the systemic application of technology to…

Requirements controlled design: A method for discovery of discontinuous system boundaries in the requirements hyperspace

NASA Astrophysics Data System (ADS)

Hollingsworth, Peter Michael

The drive toward robust systems design, especially with respect to system affordability throughout the system life-cycle, has led to the development of several advanced design methods. While these methods have been extremely successful in satisfying the needs for which they have been developed, they inherently leave a critical area unaddressed. None of them fully considers the effect of requirements on the selection of solution systems. The goal of all of current modern design methodologies is to bring knowledge forward in the design process to the regions where more design freedom is available and design changes cost less. Therefore, it seems reasonable to consider the point in the design process where the greatest restrictions are placed on the final design, the point in which the system level requirements are set. Historically the requirements have been treated as something handed down from above. However, neither the customer nor the solution provider completely understood all of the options that are available in the broader requirements space. If a method were developed that provided the ability to understand the full scope of the requirements space, it would allow for a better comparison of potential solution systems with respect to both the current and potential future requirements. The key to a requirements conscious method is to treat requirements differently from the traditional approach. The method proposed herein is known as Requirements Controlled Design (RCD). By treating the requirements as a set of variables that control the behavior of the system, instead of variables that only define the response of the system, it is possible to determine a-priori what portions of the requirements space that any given system is capable of satisfying. Additionally, it should be possible to identify which systems can satisfy a given set of requirements and the locations where a small change in one or more requirements poses a significant risk to a design program. This thesis puts forth the theory and methodology to enable RCD, and details and validates a specific method called the Modified Strength Pareto Evolutionary Algorithm (MSPEA).

Access Control Management for SCADA Systems

NASA Astrophysics Data System (ADS)

Hong, Seng-Phil; Ahn, Gail-Joon; Xu, Wenjuan

The information technology revolution has transformed all aspects of our society including critical infrastructures and led a significant shift from their old and disparate business models based on proprietary and legacy environments to more open and consolidated ones. Supervisory Control and Data Acquisition (SCADA) systems have been widely used not only for industrial processes but also for some experimental facilities. Due to the nature of open environments, managing SCADA systems should meet various security requirements since system administrators need to deal with a large number of entities and functions involved in critical infrastructures. In this paper, we identify necessary access control requirements in SCADA systems and articulate access control policies for the simulated SCADA systems. We also attempt to analyze and realize those requirements and policies in the context of role-based access control that is suitable for simplifying administrative tasks in large scale enterprises.

A spacecraft integrated power/attitude control system

NASA Technical Reports Server (NTRS)

Keckler, C. R.; Jacobs, K. L.

1974-01-01

A study to determine the viability and application of a system capable of performing the dual function of power storage/generation and attitude control has been conducted. Results from the study indicate that an integrated power/attitude control system (IPACS) can satisfy future mission requirements while providing significant savings in weight, volume, and cost over conventional systems. A failure-mode configuration of an IPACS was applied to a shuttle-launched RAM free-flyer and simulated using make-do hardware linked to a hybrid computer. Data from the simulation runs indicate that control interactions resulting from heavy power demands have minimal effect on system control effectiveness. The system was shown to be capable of meeting the stringent pointing requirements of 1 arc-second while operating under the influence of an orbital disturbance environment and during periods of momentum variations imposed by energy transfer requirements.

[Modern foreign car safety systems and their forensic-medical significance].

PubMed

Iakunin, S A

2007-01-01

The author gives a characteristic of active and passive security systems installed in cars of foreign production. These security systems significantly modify the classic car trauma character decreasing frequency of occurrence and dimensions of specific and typical injuries. A new approach based on the theory of probability to estimate these injuries is required. The most common active and passive security systems are described in the article; their principles of operation and influence on the trauma character are estimated.

Adaptive Stress Testing of Airborne Collision Avoidance Systems

NASA Technical Reports Server (NTRS)

Lee, Ritchie; Kochenderfer, Mykel J.; Mengshoel, Ole J.; Brat, Guillaume P.; Owen, Michael P.

2015-01-01

This paper presents a scalable method to efficiently search for the most likely state trajectory leading to an event given only a simulator of a system. Our approach uses a reinforcement learning formulation and solves it using Monte Carlo Tree Search (MCTS). The approach places very few requirements on the underlying system, requiring only that the simulator provide some basic controls, the ability to evaluate certain conditions, and a mechanism to control the stochasticity in the system. Access to the system state is not required, allowing the method to support systems with hidden state. The method is applied to stress test a prototype aircraft collision avoidance system to identify trajectories that are likely to lead to near mid-air collisions. We present results for both single and multi-threat encounters and discuss their relevance. Compared with direct Monte Carlo search, this MCTS method performs significantly better both in finding events and in maximizing their likelihood.

Towards an Automated Development Methodology for Dependable Systems with Application to Sensor Networks

NASA Technical Reports Server (NTRS)

Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.

2005-01-01

A general-purpose method to mechanically transform system requirements into a probably equivalent model has yet to appeal: Such a method represents a necessary step toward high-dependability system engineering for numerous possible application domains, including sensor networks and autonomous systems. Currently available tools and methods that start with a formal model of a system and mechanically produce a probably equivalent implementation are valuable but not su8cient. The "gap" unfilled by such tools and methods is that their. formal models cannot be proven to be equivalent to the system requirements as originated by the customel: For the classes of systems whose behavior can be described as a finite (but significant) set of scenarios, we offer a method for mechanically transforming requirements (expressed in restricted natural language, or in other appropriate graphical notations) into a probably equivalent formal model that can be used as the basis for code generation and other transformations.

A web platform for integrated surface water - groundwater modeling and data management

NASA Astrophysics Data System (ADS)

Fatkhutdinov, Aybulat; Stefan, Catalin; Junghanns, Ralf

2016-04-01

Model-based decision support systems are considered to be reliable and time-efficient tools for resources management in various hydrology related fields. However, searching and acquisition of the required data, preparation of the data sets for simulations as well as post-processing, visualization and publishing of the simulations results often requires significantly more work and time than performing the modeling itself. The purpose of the developed software is to combine data storage facilities, data processing instruments and modeling tools in a single platform which potentially can reduce time required for performing simulations, hence decision making. The system is developed within the INOWAS (Innovative Web Based Decision Support System for Water Sustainability under a Changing Climate) project. The platform integrates spatially distributed catchment scale rainfall - runoff, infiltration and groundwater flow models with data storage, processing and visualization tools. The concept is implemented in a form of a web-GIS application and is build based on free and open source components, including the PostgreSQL database management system, Python programming language for modeling purposes, Mapserver for visualization and publishing the data, Openlayers for building the user interface and others. Configuration of the system allows performing data input, storage, pre- and post-processing and visualization in a single not disturbed workflow. In addition, realization of the decision support system in the form of a web service provides an opportunity to easily retrieve and share data sets as well as results of simulations over the internet, which gives significant advantages for collaborative work on the projects and is able to significantly increase usability of the decision support system.

Early Engagement of Safety and Mission Assurance Expertise Using Systems Engineering Tools: A Risk-Based Approach to Early Identification of Safety and Assurance Requirements

NASA Technical Reports Server (NTRS)

Darpel, Scott; Beckman, Sean

2016-01-01

Decades of systems engineering practice have demonstrated that the earlier the identification of requirements occurs, the lower the chance that costly redesigns will needed later in the project life cycle. A better understanding of all requirements can also improve the likelihood of a design's success. Significant effort has been put into developing tools and practices that facilitate requirements determination, including those that are part of the model-based systems engineering (MBSE) paradigm. These efforts have yielded improvements in requirements definition, but have thus far focused on a design's performance needs. The identification of safety & mission assurance (S&MA) related requirements, in comparison, can occur after preliminary designs are already established, yielding forced redesigns. Engaging S&MA expertise at an earlier stage, facilitated by the use of MBSE tools, and focused on actual project risk, can yield the same type of design life cycle improvements that have been realized in technical and performance requirements.

Effects of diet forage proportion on maintenance energy requirement and the efficiency of metabolizable energy use for lactation by lactating dairy cows.

PubMed

Dong, L F; Ferris, C P; McDowell, D A; Yan, T

2015-12-01

The objective of the present study was to examine the effect of dietary forage proportion (FP) on metabolizable energy (ME) requirement for maintenance (MEm) and the efficiency of ME use for lactation (kl) in lactating dairy cows. Data used were derived from 32 calorimetric chamber experiments undertaken at our institute between 1992 and 2010, including data from 818 Holstein-Friesian cows (HF), 50 Norwegian Red cows, and 62 crossbred cows (Jersey × HF or Norwegian Red × HF). Animals were offered forage-only rations (n=66) or forage and concentrate rations (n=864) with FP ranging from 18 to 100% (dry matter basis). The effect of FP was evaluated by dividing the whole data set into 4 groups according to the FP ranges, categorized as FP <30%, FP=30 to 59%, FP=60 to 99%, and FP=100%. The MEm for individual cows was calculated from heat production minus energy losses from inefficiencies of ME use for lactation, energy retention and pregnancy, and kl was obtained from milk energy output adjusted to zero energy balance (El(0)) divided by ME available for production. Increasing FP significantly reduced ME intake and milk energy output, although the differences between the 2 low FP groups were not significant. However, increasing FP significantly increased the ratio of heat production over ME intake and MEm (MJ/kg(0.75)), with the exception that the increases did not reach significance in heat production/ME intake between FP <30% and FP=30 to 59%, or in MEm between FP=60 to 99% and FP=100%. However, the FP had no significant effect on the kl values, which were similar among the 4 groups of cows. The effect of FP was also evaluated using the linear mixed regression technique relating El(0) to ME intake. The results demonstrated that with a common regression coefficient (slope), the regression constants (intercepts) taken as net energy requirement for maintenance significantly increased with increasing FP. However, the increase between the 2 high FP groups did not research significance. It is concluded that increasing diet FP had no effects on kl but significantly increased maintenance energy requirement (MJ/kg(0.75)). These results indicate that using the current energy feeding systems to ration dairy cows managed under low input systems may underestimate their nutrient requirements, because the majority of feeding systems adopted globally do not differentiate the maintenance energy requirements between low and high forage input systems. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Application of high performance concrete in the pavement system : structural response of high performance concrete pavements.

DOT National Transportation Integrated Search

2002-03-01

Rigid pavements make up a significant percentage of highway systems in the United States and abroad. Concrete pavements provide an economical and durable solution for highway systems, because the pavements last longer and require less maintenance. Re...

Operationally Efficient Propulsion System Study (OEPSS) data book. Volume 4: OEPSS design concepts

NASA Technical Reports Server (NTRS)

Wong, George S.; Ziese, James M.; Farhangi, Shahram

1990-01-01

This study was initiated to identify operations problems and cost drivers for current propulsion systems and to identify technology and design approaches to increase the operational efficiency and reduce operations costs for future propulsion systems. To provide readily usable data for the Advanced Launch System (ALS) program, the results of the OEPSS study have been organized into a series of OEPSS Data Books. This volume describes three propulsion concepts that will simplify the propulsion system design and significantly reduce operational requirements. The concepts include: (1) a fully integrated, booster propulsion module concept for the ALS that avoids the complex system created by using autonomous engines with numerous artificial interfaces; (2) an LOX tank aft concept which avoids potentially dangerous geysering in long LOX propellant lines; and (3) an air augmented, rocket engine nozzle afterburning propulsion concept that will significantly reduce LOX propellant requirements, reduce vehicle size and simplify ground operations and ground support equipment and facilities.

Methods to Register Models and Input/Output Parameters for Integrated Modeling

EPA Science Inventory

Significant resources can be required when constructing integrated modeling systems. In a typical application, components (e.g., models and databases) created by different developers are assimilated, requiring the framework’s functionality to bridge the gap between the user’s kno...

Technical parameters for specifying imagery requirements

NASA Technical Reports Server (NTRS)

Coan, Paul P.; Dunnette, Sheri J.

1994-01-01

Providing visual information acquired from remote events to various operators, researchers, and practitioners has become progressively more important as the application of special skills in alien or hazardous situations increases. To provide an understanding of the technical parameters required to specify imagery, we have identified, defined, and discussed seven salient characteristics of images: spatial resolution, linearity, luminance resolution, spectral discrimination, temporal discrimination, edge definition, and signal-to-noise ratio. We then describe a generalizing imaging system and identified how various parts of the system affect the image data. To emphasize the different applications of imagery, we have constrasted the common television system with the significant parameters of a televisual imaging system for technical applications. Finally, we have established a method by which the required visual information can be specified by describing certain technical parameters which are directly related to the information content of the imagery. This method requires the user to complete a form listing all pertinent data requirements for the imagery.

A quantitative method for photovoltaic encapsulation system optimization

NASA Technical Reports Server (NTRS)

Garcia, A., III; Minning, C. P.; Cuddihy, E. F.

1981-01-01

It is pointed out that the design of encapsulation systems for flat plate photovoltaic modules requires the fulfillment of conflicting design requirements. An investigation was conducted with the objective to find an approach which will make it possible to determine a system with optimum characteristics. The results of the thermal, optical, structural, and electrical isolation analyses performed in the investigation indicate the major factors in the design of terrestrial photovoltaic modules. For defect-free materials, minimum encapsulation thicknesses are determined primarily by structural considerations. Cell temperature is not strongly affected by encapsulant thickness or thermal conductivity. The emissivity of module surfaces exerts a significant influence on cell temperature. Encapsulants should be elastomeric, and ribs are required on substrate modules. Aluminum is unsuitable as a substrate material. Antireflection coating is required on cell surfaces.

Bolometric detector systems for IR and mm-wave space astronomy

NASA Technical Reports Server (NTRS)

Church, S. E.; Lange, A. E.; Mauskopf, P. D.; Hristov, V.; Bock, J. J.; DelCastillo, H. M.; Beeman, J.; Ade, P. A. R.; Griffin, M. J.

1996-01-01

Recent developments in bolometric detector systems for millimeter and submillimeter wave space astronomy are described. Current technologies meet all the requirements for the high frequency instrument onboard the cosmic background radiation anisotropy satellite/satellite for the measurement of background anisotropies (COBRAS/SAMBA) platform. It is considered that the technologies that are currently being developed will significantly reduce the effective time constant and/or the cooling requirements of bolometric detectors. These technologies lend themselves to the fabrication of the large format arrays required for the Far Infrared and Submillimeter Space Telescope (FIRST). The scientific goals and detector requirements of the COBRAS/SAMBA platform that will use infrared bolometers are reviewed and the baseline detector system is described, including the feed optics, the infrared filters, the cold amplifiers and the warm readout electronics.

Identification of emergent off-nominal operational requirements during conceptual architecting of the more electric aircraft

NASA Astrophysics Data System (ADS)

Armstrong, Michael James

Increases in power demands and changes in the design practices of overall equipment manufacturers has led to a new paradigm in vehicle systems definition. The development of unique power systems architectures is of increasing importance to overall platform feasibility and must be pursued early in the aircraft design process. Many vehicle systems architecture trades must be conducted concurrent to platform definition. With an increased complexity introduced during conceptual design, accurate predictions of unit level sizing requirements must be made. Architecture specific emergent requirements must be identified which arise due to the complex integrated effect of unit behaviors. Off-nominal operating scenarios present sizing critical requirements to the aircraft vehicle systems. These requirements are architecture specific and emergent. Standard heuristically defined failure mitigation is sufficient for sizing traditional and evolutionary architectures. However, architecture concepts which vary significantly in terms of structure and composition require that unique failure mitigation strategies be defined for accurate estimations of unit level requirements. Identifying of these off-nominal emergent operational requirements require extensions to traditional safety and reliability tools and the systematic identification of optimal performance degradation strategies. Discrete operational constraints posed by traditional Functional Hazard Assessment (FHA) are replaced by continuous relationships between function loss and operational hazard. These relationships pose the objective function for hazard minimization. Load shedding optimization is performed for all statistically significant failures by varying the allocation of functional capability throughout the vehicle systems architecture. Expressing hazards, and thereby, reliability requirements as continuous relationships with the magnitude and duration of functional failure requires augmentations to the traditional means for system safety assessment (SSA). The traditional two state and discrete system reliability assessment proves insufficient. Reliability is, therefore, handled in an analog fashion: as a function of magnitude of failure and failure duration. A series of metrics are introduced which characterize system performance in terms of analog hazard probabilities. These include analog and cumulative system and functional risk, hazard correlation, and extensions to the traditional component importance metrics. Continuous FHA, load shedding optimization, and analog SSA constitute the SONOMA process (Systematic Off-Nominal Requirements Analysis). Analog system safety metrics inform both architecture optimization (changes in unit level capability and reliability) and architecture augmentation (changes in architecture structure and composition). This process was applied for two vehicle systems concepts (conventional and 'more-electric') in terms of loss/hazard relationships with varying degrees of fidelity. Application of this process shows that the traditional assumptions regarding the structure of the function loss vs. hazard relationship apply undue design bias to functions and components during exploratory design. This bias is illustrated in terms of inaccurate estimations of the system and function level risk and unit level importance. It was also shown that off-nominal emergent requirements must be defined specific to each architecture concept. Quantitative comparisons of architecture specific off-nominal performance were obtained which provide evidence to the need for accurate definition of load shedding strategies during architecture exploratory design. Formally expressing performance degradation strategies in terms of the minimization of a continuous hazard space enhances the system architects ability to accurately predict sizing critical emergent requirements concurrent to architecture definition. Furthermore, the methods and frameworks generated here provide a structured and flexible means for eliciting these architecture specific requirements during the performance of architecture trades.

Majoring in Information Systems: Reasons Why Students Select (or Not) Information Systems as a Major

ERIC Educational Resources Information Center

Snyder, Johnny; Slauson, Gayla Jo

2014-01-01

Filling the pipeline for information systems workers is critical in the information era. Projected growth rates for jobs requiring information systems expertise are significantly higher than the projected growth rates for other jobs. Why then do relatively few students choose to major in information systems? This paper reviews survey results from…

NTP comparison process

NASA Technical Reports Server (NTRS)

Corban, Robert

1993-01-01

The systems engineering process for the concept definition phase of the program involves requirements definition, system definition, and consistent concept definition. The requirements definition process involves obtaining a complete understanding of the system requirements based on customer needs, mission scenarios, and nuclear thermal propulsion (NTP) operating characteristics. A system functional analysis is performed to provide a comprehensive traceability and verification of top-level requirements down to detailed system specifications and provides significant insight into the measures of system effectiveness to be utilized in system evaluation. The second key element in the process is the definition of system concepts to meet the requirements. This part of the process involves engine system and reactor contractor teams to develop alternative NTP system concepts that can be evaluated against specific attributes, as well as a reference configuration against which to compare system benefits and merits. Quality function deployment (QFD), as an excellent tool within Total Quality Management (TQM) techniques, can provide the required structure and provide a link to the voice of the customer in establishing critical system qualities and their relationships. The third element of the process is the consistent performance comparison. The comparison process involves validating developed concept data and quantifying system merits through analysis, computer modeling, simulation, and rapid prototyping of the proposed high risk NTP subsystems. The maximum amount possible of quantitative data will be developed and/or validated to be utilized in the QFD evaluation matrix. If upon evaluation of a new concept or its associated subsystems determine to have substantial merit, those features will be incorporated into the reference configuration for subsequent system definition and comparison efforts.

Proven Innovations and New Initiatives in Ground System Development: Reducing Costs in the Ground System

NASA Technical Reports Server (NTRS)

Gunn, Jody M.

2006-01-01

The state-of-the-practice for engineering and development of Ground Systems has evolved significantly over the past half decade. Missions that challenge ground system developers with significantly reduced budgets in spite of requirements for greater and previously unimagined functionality are now the norm. Making the right trades early in the mission lifecycle is one of the key factors to minimizing ground system costs. The Mission Operations Strategic Leadership Team at the Jet Propulsion Laboratory has spent the last year collecting and working through successes and failures in ground systems for application to future missions.

Thermal control requirements for large space structures

NASA Technical Reports Server (NTRS)

Manoff, M.

1978-01-01

Performance capabilities and weight requirements of large space structure systems will be significantly influenced by thermal response characteristics. Analyses have been performed to determine temperature levels and gradients for structural configurations and elemental concepts proposed for advanced system applications ranging from relatively small, low-power communication antennas to extremely large, high-power Satellite Power Systems (SPS). Results are presented for selected platform configurations, candidate strut elements, and potential mission environments. The analyses also incorporate material and surface optical property variation. The results illustrate many of the thermal problems which may be encountered in the development of three systems.

Development of sensor augmented robotic weld systems for aerospace propulsion system fabrication

NASA Technical Reports Server (NTRS)

Jones, C. S.; Gangl, K. J.

1986-01-01

In order to meet stringent performance goals for power and reuseability, the Space Shuttle Main Engine was designed with many complex, difficult welded joints that provide maximum strength and minimum weight. To this end, the SSME requires 370 meters of welded joints. Automation of some welds has improved welding productivity significantly over manual welding. Application has previously been limited by accessibility constraints, requirements for complex process control, low production volumes, high part variability, and stringent quality requirements. Development of robots for welding in this application requires that a unique set of constraints be addressed. This paper shows how robotic welding can enhance production of aerospace components by addressing their specific requirements. A development program at the Marshall Space Flight Center combining industrial robots with state-of-the-art sensor systems and computer simulation is providing technology for the automation of welds in Space Shuttle Main Engine production.

Big system: Interactive graphics for the engineer

NASA Technical Reports Server (NTRS)

Quenneville, C. E.

1975-01-01

The BCS Interactive Graphics System (BIG System) approach to graphics was presented, along with several significant engineering applications. The BIG System precompiler, the graphics support library, and the function requirements of graphics applications are discussed. It was concluded that graphics standardization and a device independent code can be developed to assure maximum graphic terminal transferability.

Water Distribution System Operation and Maintenance. A Field Study Training Program. Second Edition.

ERIC Educational Resources Information Center

Kerri, Kenneth D.; And Others

Proper installation, inspection, operation, maintenance, repair and management of water distribution systems have a significant impact on the operation and maintenance cost and effectiveness of the systems. The objective of this manual is to provide water distribution system operators with the knowledge and skills required to operate and maintain…

Tubing vs. buckets: a cost comparison

Treesearch

Neil K. Huyler

1975-01-01

Equipment investment for tubing-vacuum systems was significantly less than that for bucket systems. Tubing-vacuum systems required about 22 percent less labor input, the major labor input being completed before sap-flow periods. Annual cost of operation was less for tubing-vacuum than the bucket system. Small tubing-vacuum operations showed more profit potential than...

Comparative Evaluation of Biomass Power Generation Systems in China Using Hybrid Life Cycle Inventory Analysis

PubMed Central

Liu, Huacai; Yin, Xiuli; Wu, Chuangzhi

2014-01-01

There has been a rapid growth in using agricultural residues as an energy source to generate electricity in China. Biomass power generation (BPG) systems may vary significantly in technology, scale, and feedstock and consequently in their performances. A comparative evaluation of five typical BPG systems has been conducted in this study through a hybrid life cycle inventory (LCI) approach. Results show that requirements of fossil energy savings, and greenhouse gas (GHG) emission reductions, as well as emission reductions of SO2 and NOx, can be best met by the BPG systems. The cofiring systems were found to behave better than the biomass-only fired system and the biomass gasification systems in terms of energy savings and GHG emission reductions. Comparing with results of conventional process-base LCI, an important aspect to note is the significant contribution of infrastructure, equipment, and maintenance of the plant, which require the input of various types of materials, fuels, services, and the consequent GHG emissions. The results demonstrate characteristics and differences of BPG systems and help identify critical opportunities for biomass power development in China. PMID:25383383

Comparative evaluation of biomass power generation systems in China using hybrid life cycle inventory analysis.

PubMed

Liu, Huacai; Yin, Xiuli; Wu, Chuangzhi

2014-01-01

There has been a rapid growth in using agricultural residues as an energy source to generate electricity in China. Biomass power generation (BPG) systems may vary significantly in technology, scale, and feedstock and consequently in their performances. A comparative evaluation of five typical BPG systems has been conducted in this study through a hybrid life cycle inventory (LCI) approach. Results show that requirements of fossil energy savings, and greenhouse gas (GHG) emission reductions, as well as emission reductions of SO2 and NOx, can be best met by the BPG systems. The cofiring systems were found to behave better than the biomass-only fired system and the biomass gasification systems in terms of energy savings and GHG emission reductions. Comparing with results of conventional process-base LCI, an important aspect to note is the significant contribution of infrastructure, equipment, and maintenance of the plant, which require the input of various types of materials, fuels, services, and the consequent GHG emissions. The results demonstrate characteristics and differences of BPG systems and help identify critical opportunities for biomass power development in China.

Dose Control System in the Optima XE Single Wafer High Energy Ion Implanter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Satoh, Shu; Yoon, Jongyoon; David, Jonathan

2011-01-07

Photoresist outgassing can significantly compromise accurate dosimetry of high energy implants. High energy implant even at a modest beam current produces high beam powers which create significantly worse outgassing than low and medium energy implants and the outgassing continues throughout the implant due to the low dose in typical high energy implant recipes. In the previous generation of high energy implanters, dose correction by monitoring of process chamber pressure during photoresist outgassing has been used. However, as applications diversify and requirements change, the need arises for a more versatile photoresist correction system to match the versatility of a single wafermore » high energy ion implanter. We have successfully developed a new dosimetry system for the Optima XE single wafer high energy ion implanter which does not require any form of compensation due to the implant conditions. This paper describes the principles and performance of this new dose system.« less

Maintenance of Surface Current Balance by Field-Aligned Thermoelectric Currents at Astronomical Bodies: Cassini at Rhea

NASA Astrophysics Data System (ADS)

Teolis, B. D.

2014-12-01

Cassini spacecraft magnetic field data at Saturn's moon Rhea reveal a field-aligned electric current system in the flux tube, which forms to satisfy the requirement to balance ion and electron currents on the moon's sharp surface. Unlike induction currents at bodies surrounded by significant atmospheres, Rhea's flux tube current system is not driven by motion through the plasma, but rather thermoelectrically, by heat flow into the object. In addition to Rhea, the requirements for the current system are easily satisfied at many plasma absorbing bodies: (1) a difference of average ion and electron gyroradii radii, and (2) a "sharp" body of any size, i.e., without a significant thick atmosphere. This type of current system is therefore expected to occur generally, e.g. at other airless planetary satellites, asteroids, and even spacecraft; and accordingly, represents a fundamental aspect of the physics of the interaction of astrophysical objects with space plasmas.

Application of high performance concrete in the pavement system : structural response of high performance concrete pavement : executive summary.

DOT National Transportation Integrated Search

2002-01-01

Rigid pavements make up a significant percentage of highway systems in the United States and abroad. Concrete pavements provide an economical and durable solution for highway systems, because the pavements last longer and require less maintenance. Re...

Satellite on-board processing for earth resources data

NASA Technical Reports Server (NTRS)

Bodenheimer, R. E.; Gonzalez, R. C.; Gupta, J. N.; Hwang, K.; Rochelle, R. W.; Wilson, J. B.; Wintz, P. A.

1975-01-01

Results of a survey of earth resources user applications and their data requirements, earth resources multispectral scanner sensor technology, and preprocessing algorithms for correcting the sensor outputs and for data bulk reduction are presented along with a candidate data format. Computational requirements required to implement the data analysis algorithms are included along with a review of computer architectures and organizations. Computer architectures capable of handling the algorithm computational requirements are suggested and the environmental effects of an on-board processor discussed. By relating performance parameters to the system requirements of each of the user requirements the feasibility of on-board processing is determined for each user. A tradeoff analysis is performed to determine the sensitivity of results to each of the system parameters. Significant results and conclusions are discussed, and recommendations are presented.

EMASS (tm): An expandable solution for NASA space data storage needs

NASA Technical Reports Server (NTRS)

Peterson, Anthony L.; Cardwell, P. Larry

1992-01-01

The data acquisition, distribution, processing, and archiving requirements of NASA and other U.S. Government data centers present significant data management challenges that must be met in the 1990's. The Earth Observing System (EOS) project alone is expected to generate daily data volumes greater than 2 Terabytes (2(10)(exp 12) Bytes). As the scientific community makes use of this data their work product will result in larger, increasingly complex data sets to be further exploited and managed. The challenge for data storage systems is to satisfy the initial data management requirements with cost effective solutions that provide for planned growth. This paper describes the expandable architecture of the E-Systems Modular Automated Storage System (EMASS (TM)), a mass storage system which is designed to support NASA's data capture, storage, distribution, and management requirements into the 21st century.

EMASS (trademark): An expandable solution for NASA space data storage needs

NASA Technical Reports Server (NTRS)

Peterson, Anthony L.; Cardwell, P. Larry

1991-01-01

The data acquisition, distribution, processing, and archiving requirements of NASA and other U.S. Government data centers present significant data management challenges that must be met in the 1990's. The Earth Observing System (EOS) project alone is expected to generate daily data volumes greater than 2 Terabytes (2 x 10(exp 12) Bytes). As the scientific community makes use of this data, their work will result in larger, increasingly complex data sets to be further exploited and managed. The challenge for data storage systems is to satisfy the initial data management requirements with cost effective solutions that provide for planned growth. The expendable architecture of the E-Systems Modular Automated Storage System (EMASS(TM)), a mass storage system which is designed to support NASA's data capture, storage, distribution, and management requirements into the 21st century is described.

MODELING AND PERFORMANCE EVALUATION FOR AVIATION SECURITY CARGO INSPECTION QUEUING SYSTEM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allgood, Glenn O; Olama, Mohammed M; Rose, Terri A

Beginning in 2010, the U.S. will require that all cargo loaded in passenger aircraft be inspected. This will require more efficient processing of cargo and will have a significant impact on the inspection protocols and business practices of government agencies and the airlines. In this paper, we conduct performance evaluation study for an aviation security cargo inspection queuing system for material flow and accountability. The overall performance of the aviation security cargo inspection system is computed, analyzed, and optimized for the different system dynamics. Various performance measures are considered such as system capacity, residual capacity, and throughput. These metrics aremore » performance indicators of the system s ability to service current needs and response capacity to additional requests. The increased physical understanding resulting from execution of the queuing model utilizing these vetted performance measures will reduce the overall cost and shipping delays associated with the new inspection requirements.« less

Development and Property Evaluation of Selected HfO2-Silicon and Rare Earth-Silicon Based Bond Coats and Environmental Barrier Coating Systems for SiC/SiC Ceramic Matrix Composites

NASA Technical Reports Server (NTRS)

Zhu, Dongming

2016-01-01

Ceramic environmental barrier coatings (EBC) and SiC/SiC ceramic matrix composites (CMCs) will play a crucial role in future aircraft propulsion systems because of their ability to significantly increase engine operating temperatures, improve component durability, reduce engine weight and cooling requirements. Advanced EBC systems for SiC/SiC CMC turbine and combustor hot section components are currently being developed to meet future turbine engine emission and performance goals. One of the significant material development challenges for the high temperature CMC components is to develop prime-reliant, high strength and high temperature capable environmental barrier coating bond coat systems, since the current silicon bond coat cannot meet the advanced EBC-CMC temperature and stability requirements. In this paper, advanced NASA HfO2-Si and rare earth Si based EBC bond coat EBC systems for SiC/SiC CMC combustor and turbine airfoil applications are investigated. High temperature properties of the advanced EBC systems, including the strength, fracture toughness, creep and oxidation resistance have been studied and summarized. The advanced NASA EBC systems showed some promise to achieve 1500C temperature capability, helping enable next generation turbine engines with significantly improved engine component temperature capability and durability.

Interference effects of vocalization on dual task performance

NASA Astrophysics Data System (ADS)

Owens, J. M.; Goodman, L. S.; Pianka, M. J.

1984-09-01

Voice command and control systems have been proposed as a potential means of off-loading the typically overburdened visual information processing system. However, prior to introducing novel human-machine interfacing technologies in high workload environments, consideration must be given to the integration of the new technologists within existing task structures to ensure that no new sources of workload or interference are systematically introduced. This study examined the use of voice interactive systems technology in the joint performance of two cognitive information processing tasks requiring continuous memory and choice reaction wherein a basis for intertask interference might be expected. Stimuli for the continuous memory task were presented aurally and either voice or keyboard responding was required in the choice reaction task. Performance was significantly degraded in each task when voice responding was required in the choice reaction time task. Performance degradation was evident in higher error scores for both the choice reaction and continuous memory tasks. Performance decrements observed under conditions of high intertask stimulus similarity were not statistically significant. The results signal the need to consider further the task requirements for verbal short-term memory when applying speech technology in multitask environments.

Basic characteristics and realization of production system control

NASA Astrophysics Data System (ADS)

Cheng, Shaopeng; Shell, Richard; Hall, Ernest L.

1992-11-01

This paper analyzes the issues involved in developing an intelligent production control system. It describes the basic characteristics of a production control system and an effective design methodology to realize the production control functions. Petri net, subsystem and hierarchical control concepts are applied to a computer integrated material handling system (MHS). Some communication and interface requirements of the MHS are also considered in this paper. The control system solution is illustrated with an actual MHS operation case which indicates that a truly flexible and integrated production system can be realized with a Petri net operation model and a hierarchical control structure. The significance of this work is related to the different operation testing and evaluation requirements encountered in manufacturing.

Trade Spaces in Crewed Spacecraft Atmosphere Revitalization System Development

NASA Technical Reports Server (NTRS)

Perry, Jay L.; Bagdigian, Robert M.; Carrasquillo, Robyn L.

2010-01-01

Developing the technological response to realizing an efficient atmosphere revitalization system for future crewed spacecraft and space habitats requires identifying and describing functional trade spaces. Mission concepts and requirements dictate the necessary functions; however, the combination and sequence of those functions possess significant flexibility. Us-ing a closed loop environmental control and life support (ECLS) system architecture as a starting basis, a functional unit operations approach is developed to identify trade spaces. Generalized technological responses to each trade space are discussed. Key performance parameters that apply to functional areas are described.

A One-year, Short-Stay Crewed Mars Mission Using Bimodal Nuclear Thermal Electric Propulsion (BNTEP) - A Preliminary Assessment

NASA Technical Reports Server (NTRS)

Burke, Laura M.; Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

2013-01-01

A crewed mission to Mars poses a significant challenge in dealing with the physiological issues that arise with the crew being exposed to a near zero-gravity environment as well as significant solar and galactic radiation for such a long duration. While long surface stay missions exceeding 500 days are the ultimate goal for human Mars exploration, short round trip, short surface stay missions could be an important intermediate step that would allow NASA to demonstrate technology as well as study the physiological effects on the crew. However, for a 1-year round trip mission, the outbound and inbound hyperbolic velocity at Earth and Mars can be very large resulting in a significant propellant requirement for a high thrust system like Nuclear Thermal Propulsion (NTP). Similarly, a low thrust Nuclear Electric Propulsion (NEP) system requires high electrical power levels (10 megawatts electric (MWe) or more), plus advanced power conversion technology to achieve the lower specific mass values needed for such a mission. A Bimodal Nuclear Thermal Electric Propulsion (BNTEP) system is examined here that uses three high thrust Bimodal Nuclear Thermal Rocket (BNTR) engines allowing short departure and capture maneuvers. The engines also generate electrical power that drives a low thrust Electric Propulsion (EP) system used for efficient interplanetary transit. This combined system can help reduce the total launch mass, system and operational requirements that would otherwise be required for equivalent NEP or Solar Electric Propulsion (SEP) mission. The BNTEP system is a hybrid propulsion concept where the BNTR reactors operate in two separate modes. During high-thrust mode operation, each BNTR provides 10's of kilo-Newtons of thrust at reasonably high specific impulse (Isp) of 900 seconds for impulsive transplanetary injection and orbital insertion maneuvers. When in power generation/EP mode, the BNTR reactors are coupled to a Brayton power conversion system allowing each reactor to generate 100's of kWe of electrical power to a very high Isp (3000 s) EP thruster system for sustained vehicle acceleration and deceleration in heliocentric space.

Enterprise Line of Sight Analysis Using Evidential Reasoning

ERIC Educational Resources Information Center

Bunting, William J.

2012-01-01

The overall direction of this research is to improve the development of information systems within federal agency modernization efforts so that the systems produce a value to the federal agency that is significantly greater upon implementation than the investment required to develop the systems. Federal agencies are modernizing at an increasing…

Moving toward climate-informed agricultural decision support - can we use PRISM data for more than just monthly averages?

USDA-ARS?s Scientific Manuscript database

Decision support systems/models for agriculture are varied in target application and complexity, ranging from simple worksheets to near real-time forecast systems requiring significant computational and manpower resources. Until recently, most such decision support systems have been constructed with...

Grid Integration Studies: Advancing Clean Energy Planning and Deployment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katz, Jessica; Chernyakhovskiy, Ilya

2016-07-01

Integrating significant variable renewable energy (VRE) into the grid requires an evolution in power system planning and operation. To plan for this evolution, power system stakeholders can undertake grid integration studies. This Greening the Grid document reviews grid integration studies, common elements, questions, and guidance for system planners.

Cardiac tamponade as an initial manifestation of systemic lupus erythematosus.

PubMed

Carrion, Diego M; Carrion, Andres F

2012-06-12

Clinical manifestations of pericardial disease may precede other signs and symptoms associated with systemic lupus erythematosus. Although pericardial effusion is one of the most common cardiac problems in patients with systemic lupus erythematosus, haemodynamically significant effusions manifesting as cardiac tamponade are rare and require prompt diagnosis and treatment.

Analysis of technology requirements and potential demand for general aviation avionics systems for operation in the 1980's

NASA Technical Reports Server (NTRS)

Cohn, D. M.; Kayser, J. H.; Senko, G. M.; Glenn, D. R.

1974-01-01

Avionics systems are identified which promise to reduce economic constraints and provide significant improvements in performance, operational capability and utility for general aviation aircraft in the 1980's.

Minimal support technology and in situ resource utilization for risk management of planetary spaceflight missions

NASA Astrophysics Data System (ADS)

Murphy, K. L.; Rygalov, V. Ye.; Johnson, S. B.

2009-04-01

All artificial systems and components in space degrade at higher rates than on Earth, depending in part on environmental conditions, design approach, assembly technologies, and the materials used. This degradation involves not only the hardware and software systems but the humans that interact with those systems. All technological functions and systems can be expressed through functional dependence: [Function]˜[ERU]∗[RUIS]∗[ISR]/[DR];where [ERU]efficiency (rate) of environmental resource utilization[RUIS]resource utilization infrastructure[ISR]in situ resources[DR]degradation rateThe limited resources of spaceflight and open space for autonomous missions require a high reliability (maximum possible, approaching 100%) for system functioning and operation, and must minimize the rate of any system degradation. To date, only a continuous human presence with a system in the spaceflight environment can absolutely mitigate those degradations. This mitigation is based on environmental amelioration for both the technology systems, as repair of data and spare parts, and the humans, as exercise and psychological support. Such maintenance now requires huge infrastructures, including research and development complexes and management agencies, which currently cannot move beyond the Earth. When considering what is required to move manned spaceflight from near Earth stations to remote locations such as Mars, what are the minimal technologies and infrastructures necessary for autonomous restoration of a degrading system in space? In all of the known system factors of a mission to Mars that reduce the mass load, increase the reliability, and reduce the mission’s overall risk, the current common denominator is the use of undeveloped or untested technologies. None of the technologies required to significantly reduce the risk for critical systems are currently available at acceptable readiness levels. Long term interplanetary missions require that space programs produce a craft with all systems integrated so that they are of the highest reliability. Right now, with current technologies, we cannot guarantee this reliability for a crew of six for 1000 days to Mars and back. Investigation of the technologies to answer this need and a focus of resources and research on their advancement would significantly improve chances for a safe and successful mission.

Requirements for AMLCDs in U.S. military applications

NASA Astrophysics Data System (ADS)

Hopper, Darrel G.; Desjardins, Daniel D.

1995-06-01

Flat panel displays are fast becoming a significant source of more defense for less money. Military instruments have begun to use color active matrix liquid crystal displays (AMLCDs). This is the beginning of a significant transition from electromechanical, CRT. dichroic LCD, and electroluminescent display designs to the AMLCD designs. We have the opportunity with this new technology to establish common products capable of meeting user requirements for sunlight-readable, color and grayscale capable, high-sharpness high-pixel count, flat panel displays for military applications. The Wright Laboratory is leading the development of recommended best practice, draft guidance standard, and performance specifications for this new generation, the flat panel cockpit display generation, of display modules based on requirements for U.S. military aircraft and ground combat human system interfaces. These requirements are similar in many regards to those in both the civil aviation and automotive industries; accordingly, commonality with these civil applications is incorporated where possible, against the requirements for military combat applications. The performance requirement may be achieved by two approaches: militarization of displays made to low requirements of a large volume civil products manufacturer like Sharp or integration of displays made to high requirements by a niche market commercial vendor, like Optical Imaging Systems, Litton Systems Limited, ImageQuest Inc., and Planar Advanced Inc. teamed with Xerox PARC and Standish Industries. [Note that the niche market companies listed are commercial off-the shelf vendors, albeit for high requirement low volume customers.] Given that the performance specifications can be met for a particular military product by either approach, the choice is based on life cycle cost and a thin analysis based on initial costs alone is not acceptable as it ignores the fact that military product life cycles and procurements are 20-60 years compared to 1.5 years for civil products. Thus far there is no convincing evidence that the large volume commercial product approach for combat systems will meet the combat performance specification or be cheaper from a life cycle cost perspective. National and economic security requirements require some military/avionic-grade AMLCD production domestically (i.e. in the U.S. and/or Canada). Examples of AMLCD demand and performance requirements in U.S. military systems are provided.

Commercial-Aircraft Protection System

NASA Astrophysics Data System (ADS)

Case, Russell L., Jr.; Wolff, Peter H.

2004-09-01

Recent world events have identified needs for a commercial aircraft defense system against Man-Portable Air Defense Systems (MANPADS), such as SA-7 and Stinger shoulder launched surface-to-air missiles. Technical challenges include target detection, identification and countermeasures. Political and societal challenges include cost, time to deployment, ground and air safety, and reliability. These challenges, as well as many others, have been met and overcome with the development of Thor Systems' Commercial-Aircraft Protection System (C-APS). C-APS makes use of commercial technology such as radar and infrared sensors with a laser-based countermeasure. Unlike adapted military systems, C-APS detects the threat long before the military versions by employing a 360 degree hemispherical scan, identifying the threat with an infrared sensor and employing a directed laser to not only deflect the target but to permanently disable its seeker. Enhanced capabilities include multiple threat elimination and closed-loop technology for kill verification. All of this is accomplished with development costs less than half that required to convert military technology, manufacturing costs significantly less than competitive products, and a maintenance cycle coincident with standard FAA requirements, which are significantly longer than current systems.

NASA's future space power needs and requirements

NASA Technical Reports Server (NTRS)

Schnyer, A. D.; Sovie, Ronald J.

1990-01-01

The National Space Policy of 1988 established the U.S.'s long-range civil space goals, and has served to guide NASA's recent planning for future space mission operations. One of the major goals was to extend the human presence beyond earth's boundaries and to advance the scientific knowledge of the solar system. A broad spectrum of potential civil space mission opportunities and interests are currently being investigated by NASA to meet the espoused goals. Participation in many of these missions requires power systems with capabilities far beyond what exists today. In other mission examples, advanced power systems technology could enhance mission performance significantly. Power system requirements and issues that need resolution to ensure eventual mission accomplishment are addressed, in conjunction with the ongoing NASA technology development efforts and the need for even greater innovative efforts to match the ambitious solar exploration mission goals. Particular attention is given to potential lunar surface operations and technology goals, based on investigations to date. It is suggested that the nuclear reactor power systems can best meet long-life requirements as well as dramatically reduce the earth-surface-to-lunar-surface transportation costs due to the lunar day/night cycle impact on the solar system's energy storage mass requirements. The state of the art of candidate power systems and elements for the lunar application and the respective exploration technology goals for mission life requirements from 10 to 25 years are examined.

Automated unit-level testing with heuristic rules

NASA Technical Reports Server (NTRS)

Carlisle, W. Homer; Chang, Kai-Hsiung; Cross, James H.; Keleher, William; Shackelford, Keith

1990-01-01

Software testing plays a significant role in the development of complex software systems. Current testing methods generally require significant effort to generate meaningful test cases. The QUEST/Ada system is a prototype system designed using CLIPS to experiment with expert system based test case generation. The prototype is designed to test for condition coverage, and attempts to generate test cases to cover all feasible branches contained in an Ada program. This paper reports on heuristics sued by the system. These heuristics vary according to the amount of knowledge obtained by preprocessing and execution of the boolean conditions in the program.

Proven Innovations and New Initiatives in Ground System Development

NASA Technical Reports Server (NTRS)

Gunn, Jody M.

2006-01-01

The state-of-the-practice for engineering and development of Ground Systems has evolved significantly over the past half decade. Missions that challenge ground system developers with significantly reduced budgets in spite of requirements for greater and previously unimagined functionality are now the norm. Making the right trades early in the mission lifecycle is one of the key factors to minimizing ground system costs. The Mission Operations Strategic Leadership Team at the Jet Propulsion Laboratory has spent the last year collecting and working through successes and failures in ground systems for application to future missions.

Nuclear electric propulsion operational reliability and crew safety study: NEP systems/modeling report

NASA Technical Reports Server (NTRS)

Karns, James

1993-01-01

The objective of this study was to establish the initial quantitative reliability bounds for nuclear electric propulsion systems in a manned Mars mission required to ensure crew safety and mission success. Finding the reliability bounds involves balancing top-down (mission driven) requirements and bottom-up (technology driven) capabilities. In seeking this balance we hope to accomplish the following: (1) provide design insights into the achievability of the baseline design in terms of reliability requirements, given the existing technology base; (2) suggest alternative design approaches which might enhance reliability and crew safety; and (3) indicate what technology areas require significant research and development to achieve the reliability objectives.

Enviromnental Control and Life Support Systems for Mars Missions - Issues and Concerns for Planetary Protection

NASA Technical Reports Server (NTRS)

Barta, Daniel J.; Anderson, Molly S.; Lange, Kevin

2015-01-01

Planetary protection represents an additional set of requirements that generally have not been considered by developers of technologies for Environmental Control and Life Support Systems (ECLSS). Planetary protection guidelines will affect the kind of operations, processes, and functions that can take place during future human planetary exploration missions. Ultimately, there will be an effect on mission costs, including the mission trade space when planetary protection requirements begin to drive vehicle deisgn in a concrete way. Planetary protection requirements need to be considered early in technology development and mission programs in order to estimate these impacts and push back on requirements or find efficient ways to perform necessary functions. It is expected that planetary protection will be a significant factor during technology selection and system architecture design for future missions.

Gas-Dynamic Designing of the Exhaust System for the Air Brake

NASA Astrophysics Data System (ADS)

Novikova, Yu; Goriachkin, E.; Volkov, A.

2018-01-01

Each gas turbine engine is tested some times during the life-cycle. The test equipment includes the air brake that utilizes the power produced by the gas turbine engine. In actual conditions, the outlet pressure of the air brake does not change and is equal to atmospheric pressure. For this reason, for the air brake work it is necessary to design the special exhaust system. Mission of the exhaust system is to provide the required level of backpressure at the outlet of the air brake. The backpressure is required for the required power utilization by the air brake (the air brake operation in the required points on the performance curves). The paper is described the development of the gas dynamic canal, designing outlet guide vane and the creation of a unified exhaust system for the air brake. Using a unified exhaust system involves moving the operating point to the performance curve further away from the calculated point. However, the applying of one exhaust system instead of two will significantly reduce the cash and time costs.

Efficacy of protaper next and protaper universal retreatment systems in removing gutta-percha in curved root canals during root canal retreatment.

PubMed

Ozyurek, Taha; Ozsezer-Demiryurek, Ebru

2017-01-01

The aim of this study was to compare the cleanliness of root canal walls after retreatment using ProTaper Next (PTN), ProTaper Universal Retreatment (PTR) nickel-titanium (NiTi) systems and Hedström hand files in curved mesial canals of mandibular molar teeth and the time required for gutta-percha and sealer removal. Ninety mandibular molar teeth with curved mesial roots were instrumented up to #35.04 with Mtwo NiTi rotary instruments and obturated using the continuous wave of condensation technique. Removal of gutta-percha and sealer was performed using one of the following: PTN and PTR NiTi systems and Hedström hand files. Samples were placed on the VistaScan phosphor plates in the mesio-distal direction and the radiographs were taken. The digital radiographs were analyzed using AutoCAD software. Also, the total time required for gutta-percha removal was calculated by a chronometer. The total retreatment time was significantly shorter in the PTN and PTR groups compared with the manual group (p<0.05). There was a significant difference between the groups according to the total residual gutta-percha and sealer (p<0.05). The PTN and PTR groups left significantly less gutta-percha and sealer remnant than the manual group (p<0.001). Within the limitations of this study, the PTN and PTR groups showed less residual gutta-percha and sealer than the manual group. The NiTi rotary systems were significantly faster than the manual group in the time required for gutta-percha and sealer removal.

Small Water System Operations and Maintenance. A Field Study Training Program. Second Edition.

ERIC Educational Resources Information Center

Kerri, Kenneth D.; And Others

Proper installation, inspection, operation, maintenance, repair and management of small water systems have a significant impact on the operation and maintenance cost and effectiveness of the systems. The objective of this manual is to provide small water system operators with the knowledge and skills required to operate and maintain these systems…

Nascom System Development Plan: System Description, Capabilities and Plans

NASA Technical Reports Server (NTRS)

1995-01-01

The NASA Communications (Nascom) System Development Plan (NSDP), reissued annually, describes the organization of Nascom, how it obtains communication services, its current systems, its relationship with other NASA centers and International Partner Agencies, some major spaceflight projects which generate significant operational communication support requirements, and major Nascom projects in various stages of development or implementation.

Fog : a review of the literature pertaining to highway problems and possible solutions.

DOT National Transportation Integrated Search

1972-01-01

1. Fogs are significant contributors to multiple car accidents that often result in fatalities. 2. Systems that adequately abate fogs or lighting systems that provide minimum visibility requirements have not evolved. 3. Most abatement techniques stem...

An evaluation of oxygen-hydrogen propulsion systems for the Space Station

NASA Technical Reports Server (NTRS)

Klemetson, R. W.; Garrison, P. W.; Hannum, N. P.

1985-01-01

Conceptual designs for O2/H2 chemical and resistojet propulsion systems for the space station was developed and evaluated. The evolution of propulsion requirements was considered as the space station configuration and its utilization as a space transportation node change over the first decade of operation. The characteristics of candidate O2/H2 auxiliary propulsion systems are determined, and opportunities for integration with the OTV tank farm and the space station life support, power and thermal control subsystems are investigated. OTV tank farm boiloff can provide a major portion of the growth station impulse requirements and CO2 from the life support system can be a significant propellant resource, provided it is not denied by closure of that subsystem. Waste heat from the thermal control system is sufficient for many propellant conditioning requirements. It is concluded that the optimum level of subsystem integration must be based on higher level space station studies.

Advanced nickel-hydrogen cell configuration study

NASA Technical Reports Server (NTRS)

1983-01-01

Long-term trends in the evolution of space power technology point toward increased payload power demand which in turn translates into both higher battery system charge storage capability and higher operating voltages. State of the art nickel-hydrogen cells of the 50 to 60 Wh size, packaged in individual pressure vessels, are capable of meeting the required cycle life for a wide range of anticipated operating conditions; however, they provided several drawbacks to battery system integrated efforts. Because of size, high voltage/high power systems require integrating hundreds of cells into the operating system. Packaging related weight and volume inefficiencies degrade the energy density and specific energy of individual cells currently at 30 Wh/cudm and 40 Wh/kg respectively. In addition, the increased parts count and associated handling significantly affect the overall battery related costs. Spacecraft battery systems designers within industry and Government realize that to reduce weight, volume, and cost requires increases in the capacity of nickel-hydrogen cells.

Extensibility of the fission surface power (FSP) system from the moon to Mars

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poston, David Irvin

2011-01-28

Fission reactors have great near-term potential to power human and robotic missions/outposts on the surface of the Moon and Mars (and potentially other planets, moons, and asteroids). The ability to provide a power-rich environment that is independent of solar intensity, nights, dust storms, etc., is of significant (perhaps enabling) importance to the further expansion of humans into our solar system. NASA's Reference Fission Surface Power (FSP) System is a 40 kWe system that has been primarily designed for lunar applications. This paper examines the extensibility of the FSP design and technology for potential missions on Mars. Possible impacts include themore » effects of changes in heat sink, gravity, day-night cycles, mission transit time, communication delay, and the chemistry of the regolith and atmosphere. One of the biggest impacts might be differences in the potential utilization of in-situ materials for shielding. Another major factor is that different missions will likely require different performance requirements, e.g. power, lifetime and mass. This paper concludes that the environmental differences between potential mission locations will not require significant changes in design and technologies, unless performance requirements for a specific mission are substantially different than those adopted for the FSP The primary basis for this conclusion is that the FSP has been designed with robust materials and design margins.« less

The Educational Implications of High Technology.

ERIC Educational Resources Information Center

Levin, Henry M.; Rumberger, Russell W.

The changes to be effected by high technology in both projected employment growth and existing jobs seem to require significant changes in the American educational system. However, government estimates for the period 1978-90 suggest that employment growth will favor jobs that require little or no training beyond the high school level (for…

Teaching to Teach History: A Study of a University-Based System of Teacher Preparation

ERIC Educational Resources Information Center

McBrady, Jared T.

2017-01-01

Both history and education courses comprise a significant portion of certification requirements for prospective history teachers. Teaching ambitiously requires mastery of many practices and bodies of knowledge, including disciplinary, pedagogical, and pedagogical content knowledge, learned in that history and education coursework. However,…

30 CFR 250.803 - Additional production system requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... ranges of pressure vessels at any time when there is a change in operating pressures that requires new... significant change in operating pressures. The most recent pressure-recorder charts used to determine... prominent place on the facility or structure. (v) For operations in subfreezing climates, the lessee shall...

Configurable e-commerce-oriented distributed seckill system with high availability

NASA Astrophysics Data System (ADS)

Zhu, Liye

2018-04-01

The rapid development of e-commerce prompted the birth of seckill activity. Seckill activity greatly stimulated public shopping desire because of its significant attraction to customers. In a seckill activity, a limited number of products will be sold at varying degrees of discount, which brings a huge temptation for customers. The discounted products are usually sold out in seconds, which can be a huge challenge for e-commerce systems. In this case, a seckill system with high concurrency and high availability has very practical significance. This research cooperates with Huijin Department Store to design and implement a seckill system of e-commerce platform. The seckill system supports high concurrency network conditions and is highly available in unexpected situation. In addition, due to the short life cycle of seckill activity, the system has the flexibility to be configured and scalable, which means that it is able to add or re-move system resources on demand. Finally, this paper carried out the function test and the performance test of the whole system. The test results show that the system meets the functional requirements and performance requirements of suppliers, administrators as well as users.

Nuclear power systems for lunar and Mars exploration

NASA Technical Reports Server (NTRS)

Sovie, R. J.; Bozek, J. M.

1990-01-01

Initial studies of a variety of mission scenarios for the new Space Exploration Initiative, and the technologies necessary to enable or significantly enhance them, have identified the development of advanced space power systems whether solar, chemical or nuclear to be of prime importance. Lightweight, compact, reliable power systems for planetary rovers and a variety of surface vehicles, utility surface power, and power for advanced propulsion systems have been identified as critical needs for these missions. These mission scenarios, the concomitant power system requirements, and power system options considered are discussed. The significant potential benefits of nuclear power are identified for meeting the power needs of the above applications.

Instrumentation and control of harmonic oscillators via a single-board microprocessor-FPGA device.

PubMed

Picone, Rico A R; Davis, Solomon; Devine, Cameron; Garbini, Joseph L; Sidles, John A

2017-04-01

We report the development of an instrumentation and control system instantiated on a microprocessor-field programmable gate array (FPGA) device for a harmonic oscillator comprising a portion of a magnetic resonance force microscope. The specific advantages of the system are that it minimizes computation, increases maintainability, and reduces the technical barrier required to enter the experimental field of magnetic resonance force microscopy. Heterodyne digital control and measurement yields computational advantages. A single microprocessor-FPGA device improves system maintainability by using a single programming language. The system presented requires significantly less technical expertise to instantiate than the instrumentation of previous systems, yet integrity of performance is retained and demonstrated with experimental data.

Instrumentation and control of harmonic oscillators via a single-board microprocessor-FPGA device

NASA Astrophysics Data System (ADS)

Picone, Rico A. R.; Davis, Solomon; Devine, Cameron; Garbini, Joseph L.; Sidles, John A.

2017-04-01

We report the development of an instrumentation and control system instantiated on a microprocessor-field programmable gate array (FPGA) device for a harmonic oscillator comprising a portion of a magnetic resonance force microscope. The specific advantages of the system are that it minimizes computation, increases maintainability, and reduces the technical barrier required to enter the experimental field of magnetic resonance force microscopy. Heterodyne digital control and measurement yields computational advantages. A single microprocessor-FPGA device improves system maintainability by using a single programming language. The system presented requires significantly less technical expertise to instantiate than the instrumentation of previous systems, yet integrity of performance is retained and demonstrated with experimental data.

Lasercom system architecture with reduced complexity

NASA Technical Reports Server (NTRS)

Lesh, James R. (Inventor); Chen, Chien-Chung (Inventor); Ansari, Homayoon (Inventor)

1994-01-01

Spatial acquisition and precision beam pointing functions are critical to spaceborne laser communication systems. In the present invention, a single high bandwidth CCD detector is used to perform both spatial acquisition and tracking functions. Compared to previous lasercom hardware design, the array tracking concept offers reduced system complexity by reducing the number of optical elements in the design. Specifically, the design requires only one detector and one beam steering mechanism. It also provides the means to optically close the point-ahead control loop. The technology required for high bandwidth array tracking was examined and shown to be consistent with current state of the art. The single detector design can lead to a significantly reduced system complexity and a lower system cost.

LaserCom System Architecture With Reduced Complexity

NASA Technical Reports Server (NTRS)

Lesh, James R. (Inventor); Chen, Chien-Chung (Inventor); Ansari, Homa-Yoon (Inventor)

1996-01-01

Spatial acquisition and precision beam pointing functions are critical to spaceborne laser communication systems. In the present invention a single high bandwidth CCD detector is used to perform both spatial acquisition and tracking functions. Compared to previous lasercom hardware design, the array tracking concept offers reduced system complexity by reducing the number of optical elements in the design. Specifically, the design requires only one detector and one beam steering mechanism. It also provides means to optically close the point-ahead control loop. The technology required for high bandwidth array tracking was examined and shown to be consistent with current state of the art. The single detector design can lead to a significantly reduced system complexity and a lower system cost.

Tracking Control and System Development for Laser-Driven Micro-Vehicles

NASA Astrophysics Data System (ADS)

Kajiwara, Itsuro; Hoshino, Kentaro; Hara, Shinji; Shiokata, Daisuke; Yabe, Takashi

The purpose of this paper is to design a control system for an integrated laser propulsion/tracking system to achieve continuous motion and control of laser-driven micro-vehicles. Laser propulsion is significant in achieving miniature and light micro-vehicles. A laser-driven micro-airplane has been studied using a paper airplane and YAG laser, resulting in successful gliding of the airplane. High-performance laser tracking control is required to achieve continuous flight. This paper presents a control design strategy based on the generalized Kalman-Yakubovic-Popov lemma to achieve this requirement. Experiments have been carried out to evaluate the performance of the integrated laser propulsion/tracking system.

Flight Validation of Mars Mission Technologies

NASA Technical Reports Server (NTRS)

Eberspeaker, P. J.

2000-01-01

Effective exploration and characterization of Mars will require the deployment of numerous surface probes, tethered balloon stations and free-flying balloon systems as well as larger landers and orbiting satellite systems. Since launch opportunities exist approximately every two years it is extremely critical that each and every mission maximize its potential for success. This will require significant testing of each system in an environment that simulates the actual operational environment as closely as possible. Analytical techniques and laboratory testing goes a long way in mitigating the inherent risks associated with space exploration, however they fall sort of accurately simulating the unpredictable operational environment in which these systems must function.

Helmet-mounted displays in long-range-target visual acquisition

NASA Astrophysics Data System (ADS)

Wilkins, Donald F.

1999-07-01

Aircrews have always sought a tactical advantage within the visual range (WVR) arena -- usually defined as 'see the opponent first.' Even with radar and interrogation foe/friend (IFF) systems, the pilot who visually acquires his opponent first has a significant advantage. The Helmet Mounted Cueing System (HMCS) equipped with a camera offers an opportunity to correct the problems with the previous approaches. By utilizing real-time image enhancement technique and feeding the image to the pilot on the HMD, the target can be visually acquired well beyond the range provided by the unaided eye. This paper will explore the camera and display requirements for such a system and place those requirements within the context of other requirements, such as weight.

Automation and integration of components for generalized semantic markup of electronic medical texts.

PubMed

Dugan, J M; Berrios, D C; Liu, X; Kim, D K; Kaizer, H; Fagan, L M

1999-01-01

Our group has built an information retrieval system based on a complex semantic markup of medical textbooks. We describe the construction of a set of web-based knowledge-acquisition tools that expedites the collection and maintenance of the concepts required for text markup and the search interface required for information retrieval from the marked text. In the text markup system, domain experts (DEs) identify sections of text that contain one or more elements from a finite set of concepts. End users can then query the text using a predefined set of questions, each of which identifies a subset of complementary concepts. The search process matches that subset of concepts to relevant points in the text. The current process requires that the DE invest significant time to generate the required concepts and questions. We propose a new system--called ACQUIRE (Acquisition of Concepts and Queries in an Integrated Retrieval Environment)--that assists a DE in two essential tasks in the text-markup process. First, it helps her to develop, edit, and maintain the concept model: the set of concepts with which she marks the text. Second, ACQUIRE helps her to develop a query model: the set of specific questions that end users can later use to search the marked text. The DE incorporates concepts from the concept model when she creates the questions in the query model. The major benefit of the ACQUIRE system is a reduction in the time and effort required for the text-markup process. We compared the process of concept- and query-model creation using ACQUIRE to the process used in previous work by rebuilding two existing models that we previously constructed manually. We observed a significant decrease in the time required to build and maintain the concept and query models.

NASA Office of Aeronautics and Space Technology Summer Workshop. Executive summary. [in-space research using the Space Transportation System

NASA Technical Reports Server (NTRS)

1975-01-01

Research and technology investigations are identified in eleven discipline technologies which require or which could significantly benefit from an in-space experiment, systems demonstrations, or component test using the Space Transportation System. Synopses of the eleven technology panels reports are presented.

CATO--A General User Interface for CAS

ERIC Educational Resources Information Center

Janetzko, Hans-Dieter

2015-01-01

CATO is a new user interface, developed by the author as a response to the significant difficulties faced by scientists, engineers, and students in their usage of computer algebra (CA) systems. Their tendency to use CA systems only occasionally means that they are unfamiliar with requisite grammar and syntax these systems require. The author…

Towards Next Generation Activity-Based Learning Systems

ERIC Educational Resources Information Center

Sampson, Demetrios G.; Karampiperis, Pythagoras

2006-01-01

The need for e-learning systems that support a diverse set of pedagogical requirements has been identified as an important issue in web-based education. Until now, significant research and development effort has been devoted to aiming towards web-based educational systems tailored to specific pedagogical approaches. The most advanced of them are…

Cardiac tamponade as an initial manifestation of systemic lupus erythematosus

PubMed Central

Carrion, Diego M; Carrion, Andres F

2012-01-01

Clinical manifestations of pericardial disease may precede other signs and symptoms associated with systemic lupus erythematosus. Although pericardial effusion is one of the most common cardiac problems in patients with systemic lupus erythematosus, haemodynamically significant effusions manifesting as cardiac tamponade are rare and require prompt diagnosis and treatment. PMID:22693326

Identifiability of conservative linear mechanical systems. [applied to large flexible spacecraft structures

NASA Technical Reports Server (NTRS)

Sirlin, S. W.; Longman, R. W.; Juang, J. N.

1985-01-01

With a sufficiently great number of sensors and actuators, any finite dimensional dynamic system is identifiable on the basis of input-output data. It is presently indicated that, for conservative nongyroscopic linear mechanical systems, the number of sensors and actuators required for identifiability is very large, where 'identifiability' is understood as a unique determination of the mass and stiffness matrices. The required number of sensors and actuators drops by a factor of two, given a relaxation of the identifiability criterion so that identification can fail only if the system parameters being identified lie in a set of measure zero. When the mass matrix is known a priori, this additional information does not significantly affect the requirements for guaranteed identifiability, though the number of parameters to be determined is reduced by a factor of two.

xLuna - D emonstrator on ESA Mars Rover

NASA Astrophysics Data System (ADS)

Braga, P.; Henriques, L.; Carvalho, B.; Chevalley, P.; Zulianello, M.

2008-08-01

There is a significant gap between the services offered by existing space qualified Real-Time Operating Systems (RTOS) and those required by the most demanding future space applications. New requirements for autonomy, terrain mapping and navigation, Simultaneous Location and Mapping (SLAM), improvement of the throughput of science tasks, all demand high level services such as file systems or POSIX compliant interfaces. xLuna is an operating system that aims fulfilling these new requirements. Besides providing the typical services that of an RTOS (tasks and interrupts management, timers, message queues, etc), it also includes most of the features available in modern general-purpose operating systems, such as Linux. This paper describes a case study that proposes to demonstrate the usage of xLuna on board a rover currently in use for the development of algorithms in preparation of a mission to Mars.

Advanced Life Support Technologies and Scenarios

NASA Technical Reports Server (NTRS)

Barta, Daniel J.

2011-01-01

As NASA looks beyond the International Space Station toward long-duration, deep space missions away from Earth, the current practice of supplying consumables and spares will not be practical nor affordable. New approaches are sought for life support and habitation systems that will reduce dependency on Earth and increase mission sustainability. To reduce launch mass, further closure of Environmental Control and Life Support Systems (ECLSS) beyond the current capability of the ISS will be required. Areas of particular interest include achieving higher degrees of recycling within Atmosphere Revitalization, Water Recovery and Waste Management Systems. NASA is currently investigating advanced carbon dioxide reduction processes that surpass the level of oxygen recovery available from the Sabatier Carbon Dioxide Reduction Assembly (CRA) on the ISS. Improving the efficiency of the recovery of water from spacecraft solid and liquid wastes is possible through use of emerging technologies such as the heat melt compactor and brine dewatering systems. Another significant consumable is that of food. Food production systems based on higher plants may not only contribute significantly to the diet, but also contribute to atmosphere revitalization, water purification and waste utilization. Bioreactors may be potentially utilized for wastewater and solid waste management. The level at which bioregenerative technologies are utilized will depend on their comparative requirements for spacecraft resources including mass, power, volume, heat rejection, crew time and reliability. Planetary protection requirements will need to be considered for missions to other solar system bodies.

Effect of power system technology and mission requirements on high altitude long endurance aircraft

NASA Technical Reports Server (NTRS)

Colozza, Anthony J.

1994-01-01

An analysis was performed to determine how various power system components and mission requirements affect the sizing of a solar powered long endurance aircraft. The aircraft power system consists of photovoltaic cells and a regenerative fuel cell. Various characteristics of these components, such as PV cell type, PV cell mass, PV cell efficiency, fuel cell efficiency, and fuel cell specific mass, were varied to determine what effect they had on the aircraft sizing for a given mission. Mission parameters, such as time of year, flight altitude, flight latitude, and payload mass and power, were also altered to determine how mission constraints affect the aircraft sizing. An aircraft analysis method which determines the aircraft configuration, aspect ratio, wing area, and total mass, for maximum endurance or minimum required power based on the stated power system and mission parameters is presented. The results indicate that, for the power system, the greatest benefit can be gained by increasing the fuel cell specific energy. Mission requirements also substantially affect the aircraft size. By limiting the time of year the aircraft is required to fly at high northern or southern latitudes, a significant reduction in aircraft size or increase in payload capacity can be achieved.

Knowledge-based system V and V in the Space Station Freedom program

NASA Technical Reports Server (NTRS)

Kelley, Keith; Hamilton, David; Culbert, Chris

1992-01-01

Knowledge Based Systems (KBS's) are expected to be heavily used in the Space Station Freedom Program (SSFP). Although SSFP Verification and Validation (V&V) requirements are based on the latest state-of-the-practice in software engineering technology, they may be insufficient for Knowledge Based Systems (KBS's); it is widely stated that there are differences in both approach and execution between KBS V&V and conventional software V&V. In order to better understand this issue, we have surveyed and/or interviewed developers from sixty expert system projects in order to understand the differences and difficulties in KBS V&V. We have used this survey results to analyze the SSFP V&V requirements for conventional software in order to determine which specific requirements are inappropriate for KBS V&V and why they are inappropriate. Further work will result in a set of recommendations that can be used either as guidelines for applying conventional software V&V requirements to KBS's or as modifications to extend the existing SSFP conventional software V&V requirements to include KBS requirements. The results of this work are significant to many projects, in addition to SSFP, which will involve KBS's.

CHEMICAL ENHANCEMENTS TO PUMP-AND-TREAT REMEDIATION

EPA Science Inventory

Conventional pump-and-treat technologies are among the most widely used systems for the remediation of contaminated ground-water. ithin recent years it has become recognized that these systems can require protracted periods of time to make significant reductions in the quantity o...

Development of 3000 m Subsea Blowout Preventer Experimental Prototype

NASA Astrophysics Data System (ADS)

Cai, Baoping; Liu, Yonghong; Huang, Zhiqian; Ma, Yunpeng; Zhao, Yubin

2017-12-01

A subsea blowout preventer experimental prototype is developed to meet the requirement of training operators, and the prototype consists of hydraulic control system, electronic control system and small-sized blowout preventer stack. Both the hydraulic control system and the electronic system are dual-mode redundant systems. Each system works independently and is switchable when there are any malfunctions. And it significantly improves the operation reliability of the equipment.

Towards improving software security by using simulation to inform requirements and conceptual design

DOE PAGES

Nutaro, James J.; Allgood, Glenn O.; Kuruganti, Teja

2015-06-17

We illustrate the use of modeling and simulation early in the system life-cycle to improve security and reduce costs. The models that we develop for this illustration are inspired by problems in reliability analysis and supervisory control, for which similar models are used to quantify failure probabilities and rates. In the context of security, we propose that models of this general type can be used to understand trades between risk and cost while writing system requirements and during conceptual design, and thereby significantly reduce the need for expensive security corrections after a system enters operation

Determination of $sup 241$Am in soil using an automated nuclear radiation measurement laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Engstrom, D.E.; White, M.G.; Dunaway, P.B.

The recent completion of REECo's Automated Laboratory and associated software systems has provided a significant increase in capability while reducing manpower requirements. The system is designed to perform gamma spectrum analyses on the large numbers of samples required by the current Nevada Applied Ecology Group (NAEG) and Plutonium Distribution Inventory Program (PDIP) soil sampling programs while maintaining sufficient sensitivities as defined by earlier investigations of the same type. The hardware and systems are generally described in this paper, with emphasis being placed on spectrum reduction and the calibration procedures used for soil samples. (auth)

A Formal Approach to Requirements-Based Programming

NASA Technical Reports Server (NTRS)

Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.

2005-01-01

No significant general-purpose method is currently available to mechanically transform system requirements into a provably equivalent model. The widespread use of such a method represents a necessary step toward high-dependability system engineering for numerous application domains. Current tools and methods that start with a formal model of a system and mechanically produce a provably equivalent implementation are valuable but not sufficient. The "gap" unfilled by such tools and methods is that the formal models cannot be proven to be equivalent to the requirements. We offer a method for mechanically transforming requirements into a provably equivalent formal model that can be used as the basis for code generation and other transformations. This method is unique in offering full mathematical tractability while using notations and techniques that are well known and well trusted. Finally, we describe further application areas we are investigating for use of the approach.

Study of solar array switching power management technology for space power system

NASA Technical Reports Server (NTRS)

Cassinelli, J. E.

1982-01-01

This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts were identified that could safisfy the mission requirements. These switching concepts were compared with a conventional buck regulator system on the basis of cost, weight and volume, reliability, efficiency and thermal control. For the missions reviewed, solar array switching provided significant advantages in all areas of comparison.

Study of solar array switching power management technology for space power system

NASA Technical Reports Server (NTRS)

Cassinelli, J. E.

1982-01-01

This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts which could satisfy the mission requirements were identified. The switching concepts were compared with a conventional buck regulator system for cost, weight and volume, reliability, efficiency and thermal control. Solar array switching provided significant advantages in all areas of comparison for the reviewed missions.

Assessment of Alternate Thermal Protection Systems for the Space Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Kelly, H. N.; Webb, G. L.

1982-01-01

Candidate concepts are identified. The impact on the Shuttle Orbiter performance life cycle cost, and risk was assessed and technology advances required to bring the selected TPS to operational readiness are defined. The best system is shown to be a hybrid blend of metallic and carbon-carbon TPS concepts. These alternate concepts offer significant improvements in reusability and are mass competitive with the current ceramic tile reusable surface insulation. Programmatic analysis indicates approximately five years are required to bring the concepts to operational readiness.

Solar applications analysis for energy storage

NASA Technical Reports Server (NTRS)

Blanchard, T.

1980-01-01

The role of energy storage as it relates to solar energy systems is considered. Storage technologies to support solar energy applications, the status of storage technologies, requirements and specifications for storage technologies, and the adequacy of the current storage research and development program to meet these requirements are among the factors discussed. Emphasis is placed on identification of where the greatest potential exists for energy storage in support of those solar energy systems which could have a significant impact on the U.S. energy mix.

From Worker Health To Citizen Health: Moving Upstream

PubMed Central

Sepulveda, Martin-Jose

2014-01-01

New rapid growth economies, urbanization, health systems crises and “big data” are causing fundamental changes in social structures and systems including health. These forces for change have significant consequences for occupational and environmental medicine and will challenge the specialty to think beyond workers and workplaces as the principal locus of innovation for health and performance. These trends are placing great emphasis on upstream strategies for addressing the complex systems dynamics of the social determinants of health. The need to engage systems in communities for healthier workforces is a shift in orientation from worker and workplace centric to citizen and community centric. This change for occupational and environmental medicine requires extending systems approaches in the workplace to communities which are systems of systems and which require different skills, data, tools and partnerships. PMID:24284749

From worker health to citizen health: moving upstream.

PubMed

Sepulveda, Martin-Jose

2013-12-01

New rapid growth economies, urbanization, health systems crises, and "big data" are causing fundamental changes in social structures and systems, including health. These forces for change have significant consequences for occupational and environmental medicine and will challenge the specialty to think beyond workers and workplaces as the principal locus of innovation for health and performance. These trends are placing great emphasis on upstream strategies for addressing the complex systems dynamics of the social determinants of health. The need to engage systems in communities for healthier workforces is a shift in orientation from worker and workplace centric to citizen and community centric. This change for occupational and environmental medicine requires extending systems approaches in the workplace to communities that are systems of systems and that require different skills, data, tools, and partnerships.

Internal quality control: best practice.

PubMed

Kinns, Helen; Pitkin, Sarah; Housley, David; Freedman, Danielle B

2013-12-01

There is a wide variation in laboratory practice with regard to implementation and review of internal quality control (IQC). A poor approach can lead to a spectrum of scenarios from validation of incorrect patient results to over investigation of falsely rejected analytical runs. This article will provide a practical approach for the routine clinical biochemistry laboratory to introduce an efficient quality control system that will optimise error detection and reduce the rate of false rejection. Each stage of the IQC system is considered, from selection of IQC material to selection of IQC rules, and finally the appropriate action to follow when a rejection signal has been obtained. The main objective of IQC is to ensure day-to-day consistency of an analytical process and thus help to determine whether patient results are reliable enough to be released. The required quality and assay performance varies between analytes as does the definition of a clinically significant error. Unfortunately many laboratories currently decide what is clinically significant at the troubleshooting stage. Assay-specific IQC systems will reduce the number of inappropriate sample-run rejections compared with the blanket use of one IQC rule. In practice, only three or four different IQC rules are required for the whole of the routine biochemistry repertoire as assays are assigned into groups based on performance. The tools to categorise performance and assign IQC rules based on that performance are presented. Although significant investment of time and education is required prior to implementation, laboratories have shown that such systems achieve considerable reductions in cost and labour.

Analysis of Stationary, Photovoltaic-based Surface Power System Designs at the Lunar South Pole

NASA Technical Reports Server (NTRS)

Freeh, Joshua E.

2009-01-01

Combinations of solar arrays and either batteries or regenerative fuel cells are analyzed for a surface power system module at the lunar south pole. The systems are required to produce 5 kW of net electrical power in sunlight and 2 kW of net electrical power during lunar night periods for a 10-year period between 2020 and 2030. Systems-level models for energy conservation, performance, degradation, and mass are used to compare to various systems. The sensitivities of important and/or uncertain variables including battery specific energy, fuel cell operating voltage, and DC-DC converter efficiency are compared to better understand the system. Switching unit efficiency, battery specific energy, and fuel cell operating voltage appear to be important system-level variables for this system. With reasonably sized solar arrays, the regenerative fuel cell system has significantly lower mass than the battery system based on the requirements and assumptions made herein. The total operational time is estimated at about 10,000 hours in battery discharge/fuel cell mode and about 4,000 and 8,000 hours for the battery charge and electrolyzer modes, respectively. The estimated number of significant depth-of-discharge cycles for either energy storage system is less than 100 for the 10-year period.

Transverse vs torsional ultrasound: prospective randomized contralaterally controlled study comparing two phacoemulsification-system handpieces.

PubMed

Assil, Kerry K; Harris, Lindsay; Cecka, Jeannie

2015-01-01

To compare surgical efficiency and multiple early clinical outcome variables in eyes undergoing phacoemulsification using either transversal or torsional ultrasound systems. Assil Eye Institute, Beverly Hills, CA, USA. Prospective, randomized, clinician-masked, contralaterally controlled single-center evaluation. Patients seeking cataract removal in both eyes with implantation of multifocal intraocular lenses were randomly assigned to one of two treatment rooms for phacoemulsification with either a transverse ultrasound system or torsional handpiece system. The contralateral eye was treated at a later date with the alternate device. A total of 54 eyes of 27 patients having similar degrees of cataract, astigmatism, and visual potential were included. All operative data were collected for analysis, and patients were followed for 3 months after surgery. Similar visual acuity was reported at all postoperative visits between the two groups. Mean phacoemulsification time and total power required were both significantly lower with the transverse system than with the torsional technique (P<0.05 for both). Similarly, mean total balanced salt solution used was significantly less with the transverse system vs torsional (P<0.05). Postoperative safety demonstrated significantly lower endothelial cell loss at 1 day and 1 month (P<0.05) with transverse vs torsional. Macular swelling was less at 1 week, 1 month, and 3 months with transverse vs torsional, although the difference did not achieve significance (P=0.1) at any single time point. Clinically detectable corneal edema was reported less frequently at all postoperative time points with the transverse system. The transverse ultrasound system was found to be possibly associated with less balanced salt-solution use, less phacoemulsification time, and less power required than the torsional phaco system. Postoperative data suggested that improved phaco efficiency may translate to a better overall safety profile for the patient.

Tangential blowing for control of strong normal shock - Boundary layer interactions on inlet ramps

NASA Technical Reports Server (NTRS)

Schwendemann, M. F.; Sanders, B. W.

1982-01-01

The use of tangential blowing from a row of holes in an aft facing step is found to provide good control of the ramp boundary layer, normal shock interaction on a fixed geometry inlet over a wide range of inlet mass flow ratios. Ramp Mach numbers of 1.36 and 1.96 are investigated. The blowing geometry is found to have a significant effect on system performance at the highest Mach number. The use of high-temperature air in the blowing system, however, has only a slight effect on performance. The required blowing rates are significantly high for the most severe test conditions. In addition, the required blowing coefficient is found to be proportional to the normal shock pressure rise.

Recombination Catalysts for Hypersonic Fuels

NASA Technical Reports Server (NTRS)

Chinitz, W.

1998-01-01

The goal of commercially-viable access to space will require technologies that reduce propulsion system weight and complexity, while extracting maximum energy from the products of combustion. This work is directed toward developing effective nozzle recombination catalysts for the supersonic and hypersonic aeropropulsion engines used to provide such access to space. Effective nozzle recombination will significantly reduce rk=le length (hence, propulsion system weight) and reduce fuel requirements, further decreasing the vehicle's gross lift-off weight. Two such catalysts have been identified in this work, barium and antimony compounds, by developing chemical kinetic reaction mechanisms for these materials and determining the engine performance enhancement for a typical flight trajectory. Significant performance improvements are indicated, using only 2% (mole or mass) of these compounds in the combustor product gas.

The Future Impact of Wind on BPA Power System Ancillary Services

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makarov, Yuri V.; Lu, Shuai; McManus, Bart

Wind power is growing in a very fast pace as an alternative generating resource. As the ratio of wind power over total system capacity increases, the impact of wind on various system aspects becomes significant. This paper presents a methodology to study the future impact of wind on BPA power system ancillary services including load following and regulation. Existing approaches for similar analysis include dispatch model simulation and standard deviation evaluation. The methodology proposed in this paper uses historical data and stochastic processes to simulate the load balancing processes in BPA power system. Then capacity, ramp rate and ramp durationmore » characteristics are extracted from the simulation results, and load following and regulation requirements are calculated accordingly. It mimics the actual power system operations therefore the results can be more realistic yet the approach is convenient to perform. Further, the ramp rate and ramp duration data obtained from the analysis can be used to evaluate generator response or maneuverability and energy requirement, respectively, additional to the capacity requirement.« less

Operation and maintenance requirements of the Army Remotely Piloted Vehicle (RPV)

NASA Technical Reports Server (NTRS)

1983-01-01

The Remotely Piloted Vehicle (RPV) system is being developed to provide the Army with a target acquistion, target location, and laser designation capability that will significantly enhance the effectiveness of the artillery. Iterative analyses of the manpower, personnel, and training (MPT) requirements for an RPV system configured to accommodate both a daylight television and a forward looking infrared (FLIR) mission payload subsystem (FMPS) and related support subsystems are examined. Additionally, this analysis incorporates a 24 hour-a-day operational scenario. Therefore, the information presented was developed with a view towards delineating the differences (or deltas) imposed by the new requirements resulting from FMPS/24 hour operating day functions.

Liquid rocket booster integration study. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1988-01-01

The impacts of introducing liquid rocket booster engines (LRB) into the Space Transportation System (STS)/Kennedy Space Center (KSC) launch environment are identified and evaluated. Proposed ground systems configurations are presented along with a launch site requirements summary. Prelaunch processing scenarios are described and the required facility modifications and new facility requirements are analyzed. Flight vehicle design recommendations to enhance launch processing are discussed. Processing approaches to integrate LRB with existing STS launch operations are evaluated. The key features and significance of launch site transition to a new STS configuration in parallel with ongoing launch activities are enumerated. This volume is the executive summary of the five volume series.

Liquid rocket booster integration study. Volume 5, part 1: Appendices

NASA Technical Reports Server (NTRS)

1988-01-01

The impacts of introducing liquid rocket booster engines (LRB) into the Space Transportation System (STS)/Kennedy Space Center (KSC) launch environment are identified and evaluated. Proposed ground systems configurations are presented along with a launch site requirements summary. Prelaunch processing scenarios are described and the required facility modifications and new facility requirements are analyzed. Flight vehicle design recommendations to enhance launch processing are discussed. Processing approaches to integrate LRB with existing STS launch operations are evaluated. The key features and significance of launch site transition to a new STS configuration in parallel with ongoing launch activities are enumerated. This volume is the appendices of the five volume series.

Liquid Rocket Booster Integration Study. Volume 2: Study synopsis

NASA Technical Reports Server (NTRS)

1988-01-01

The impacts of introducing liquid rocket booster engines (LRB) into the Space Transportation System (STS)/Kennedy Space Center (KSC) launch environment are identified and evaluated. Proposed ground systems configurations are presented along with a launch site requirements summary. Prelaunch processing scenarios are described and the required facility modifications and new facility requirements are analyzed. Flight vehicle design recommendations to enhance launch processing are discussed. Processing approaches to integrate LRB with existing STS launch operations are evaluated. The key features and significance of launch site transition to a new STS configuration in parallel with ongoing launch activities are enumerated. This volume is the study summary of the five volume series.

SP-100 - The national space reactor power system program in response to future needs

NASA Astrophysics Data System (ADS)

Armijo, J. S.; Josloff, A. T.; Bailey, H. S.; Matteo, D. N.

The SP-100 system has been designed to meet comprehensive and demanding NASA/DOD/DOE requirements. The key requirements include: nuclear safety for all mission phases, scalability from 10's to 100's of kWe, reliable performance at full power for seven years of partial power for ten years, survivability in civil or military threat environments, capability to operate autonomously for up to six months, capability to protect payloads from excessive radiation, and compatibility with shuttle and expendable launch vehicles. The authors address of major progress in terms of design, flexibility/scalability, survivability, and development. These areas, with the exception of survivability, are discussed in detail. There has been significant improvement in the generic flight system design with substantial mass savings and simplification that enhance performance and reliability. Design activity has confirmed the scalability and flexibility of the system and the ability to efficiently meet NASA, AF, and SDIO needs. SP-100 development continues to make significant progress in all key technology areas.

Role of public involvement in the limits of acceptable change wilderness planning system

Treesearch

Edwin E. Krumpe; Stephen F. McCool

1997-01-01

Implementation of the LAC within politicized contexts requires that managers/planners involve the public in ways significantly different from the traditional rational-comprehensive paradigm of natural resource planning. In politicized contexts, the lack of clear agreement about goals and disagreement among scientists about cause-effect relationships requires planning...

TARGET's role in knowledge acquisition, engineering, validation, and documentation

NASA Technical Reports Server (NTRS)

Levi, Keith R.

1994-01-01

We investigate the use of the TARGET task analysis tool for use in the development of rule-based expert systems. We found TARGET to be very helpful in the knowledge acquisition process. It enabled us to perform knowledge acquisition with one knowledge engineer rather than two. In addition, it improved communication between the domain expert and knowledge engineer. We also found it to be useful for both the rule development and refinement phases of the knowledge engineering process. Using the network in these phases required us to develop guidelines that enabled us to easily translate the network into production rules. A significant requirement for TARGET remaining useful throughout the knowledge engineering process was the need to carefully maintain consistency between the network and the rule representations. Maintaining consistency not only benefited the knowledge engineering process, but also has significant payoffs in the areas of validation of the expert system and documentation of the knowledge in the system.

Return of Individual Research Results and Incidental Findings in the Clinical Trials Cooperative Group Setting

PubMed Central

Ferriere, Michael; Van Ness, Brian

2013-01-01

The NCI funded cooperative group cancer clinical trial system develops experimental therapies and often collects patient samples for correlative research. The Cooperative Group Bank (CGB) system maintains biobanks with a current policy not to return research results to individuals. An online survey was created, and 10 directors of CGBs completed the surveys asking about understanding and attitudes in changing policies to consider return of Incidental Findings (IFs) and Individual Research Results (IRRs) of health significance. The potential impact of the ten consensus recommendations of Wolf et al. presented in this issue are examined. Re-identification of samples is often not problematic; however, changes to the current banking and clinical trial systems would require significant effort to fulfill an obligation of recontact of subjects. Additional resources, as well as a national advisory board would be required to standardize implementation. PMID:22382800

An Inverter Packaging Scheme for an Integrated Segmented Traction Drive System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, Gui-Jia; Tang, Lixin; Ayers, Curtis William

The standard voltage source inverter (VSI), widely used in electric vehicle/hybrid electric vehicle (EV/HEV) traction drives, requires a bulky dc bus capacitor to absorb the large switching ripple currents and prevent them from shortening the battery s life. The dc bus capacitor presents a significant barrier to meeting inverter cost, volume, and weight requirements for mass production of affordable EVs/HEVs. The large ripple currents become even more problematic for the film capacitors (the capacitor technology of choice for EVs/HEVs) in high temperature environments as their ripple current handling capability decreases rapidly with rising temperatures. It is shown in previous workmore » that segmenting the VSI based traction drive system can significantly decrease the ripple currents and thus the size of the dc bus capacitor. This paper presents an integrated packaging scheme to reduce the system cost of a segmented traction drive.« less

High performance VLSI telemetry data systems

NASA Technical Reports Server (NTRS)

Chesney, J.; Speciale, N.; Horner, W.; Sabia, S.

1990-01-01

NASA's deployment of major space complexes such as Space Station Freedom (SSF) and the Earth Observing System (EOS) will demand increased functionality and performance from ground based telemetry acquisition systems well above current system capabilities. Adaptation of space telemetry data transport and processing standards such as those specified by the Consultative Committee for Space Data Systems (CCSDS) standards and those required for commercial ground distribution of telemetry data, will drive these functional and performance requirements. In addition, budget limitations will force the requirement for higher modularity, flexibility, and interchangeability at lower cost in new ground telemetry data system elements. At NASA's Goddard Space Flight Center (GSFC), the design and development of generic ground telemetry data system elements, over the last five years, has resulted in significant solutions to these problems. This solution, referred to as the functional components approach includes both hardware and software components ready for end user application. The hardware functional components consist of modern data flow architectures utilizing Application Specific Integrated Circuits (ASIC's) developed specifically to support NASA's telemetry data systems needs and designed to meet a range of data rate requirements up to 300 Mbps. Real-time operating system software components support both embedded local software intelligence, and overall system control, status, processing, and interface requirements. These components, hardware and software, form the superstructure upon which project specific elements are added to complete a telemetry ground data system installation. This paper describes the functional components approach, some specific component examples, and a project example of the evolution from VLSI component, to basic board level functional component, to integrated telemetry data system.

Costs, needs must be balanced when buying computer systems.

PubMed

Krantz, G M; Doyle, J J; Stone, S G

1989-06-01

A healthcare institution must carefully examine its internal needs and external requirements before selecting an information system. The system's costs must be carefully weighed because significant computer cost overruns can cripple overall hospital finances. A New Jersey hospital carefully studied these issues and determined that a contract with a regional data center was its best option.

The challenge of developing structural materials for fusion power systems

NASA Astrophysics Data System (ADS)

Bloom, Everett E.

1998-10-01

Nuclear fusion can be one of the most attractive sources of energy from the viewpoint of safety and minimal environmental impact. Central in the goal of designing a safe, environmentally benign, and economically competitive fusion power system is the requirement for high performance, low activation materials. The general performance requirements for such materials have been defined and it is clear that materials developed for other applications (e.g. aerospace, nuclear fission, fossil energy systems) will not fully meet the needs of fusion. Advanced materials, with composition and microstructure tailored to yield properties that will satisfy the specific requirements of fusion must be developed. The international fusion programs have made significant progress towards this goal. Compositional requirements for low activation lead to a focus of development efforts on silicon carbide composites, vanadium alloys, and advanced martensitic steels as candidate structural material systems. Control of impurities will be critically important in actually achieving low activation but this appears possible. Neutron irradiation produces significant changes in the mechanical and physical properties of each of these material systems raising feasibility questions and design limitations. A focus of the research and development effort is to understand these effects, and through the development of specific compositions and microstructures, produce materials with improved and adequate performance. Other areas of research that are synergistic with the development of radiation resistant materials include fabrication, joining technology, chemical compatibility with coolants and tritium breeders and specific questions relating to the unique characteristics of a given material (e.g. coatings to reduce gas permeation in SiC composites) or design concept (e.g. electrical insulator coatings for liquid metal concepts).

Implementation of a low-cost, commercial orbit determination system

NASA Astrophysics Data System (ADS)

Corrigan, Jim

1994-11-01

Traditional satellite and launch control systems have consisted of custom solutions requiring significant development and maintenance costs. These systems have typically been designed to support specific program requirements and are expensive to modify and augment after delivery. The expanding role of space in today's marketplace combined with the increased sophistication and capabilities of modern satellites has created a need for more efficient, lower cost solutions to complete command and control systems. Recent technical advances have resulted in commercial-off-the-shelf products which greatly reduce the complete life-cycle costs associated with satellite launch and control system procurements. System integrators and spacecraft operators have, however, been slow to integrate these commercial based solutions into a comprehensive command and control system. This is due, in part, to a resistance to change and the fact that many available products are unable to effectively communicate with other commercial products. The United States Air Force, responsible for the health and safety of over 84 satellites via its Air Force Satellite Control Network (AFSCN), has embarked on an initiative to prove that commercial products can be used effectively to form a comprehensive command and control system. The initial version of this system is being installed at the Air Force's Center for Research Support (CERES) located at the National Test Facility in Colorado Springs, Colorado. The first stage of this initiative involved the identification of commercial products capable of satisfying each functional element of a command and control system. A significant requirement in this product selection criteria was flexibility and ability to integrate with other available commercial products. This paper discusses the functions and capabilities of the product selected to provide orbit determination functions for this comprehensive command and control system.

Implementation of a low-cost, commercial orbit determination system

NASA Technical Reports Server (NTRS)

Corrigan, Jim

1994-01-01

Traditional satellite and launch control systems have consisted of custom solutions requiring significant development and maintenance costs. These systems have typically been designed to support specific program requirements and are expensive to modify and augment after delivery. The expanding role of space in today's marketplace combined with the increased sophistication and capabilities of modern satellites has created a need for more efficient, lower cost solutions to complete command and control systems. Recent technical advances have resulted in commercial-off-the-shelf products which greatly reduce the complete life-cycle costs associated with satellite launch and control system procurements. System integrators and spacecraft operators have, however, been slow to integrate these commercial based solutions into a comprehensive command and control system. This is due, in part, to a resistance to change and the fact that many available products are unable to effectively communicate with other commercial products. The United States Air Force, responsible for the health and safety of over 84 satellites via its Air Force Satellite Control Network (AFSCN), has embarked on an initiative to prove that commercial products can be used effectively to form a comprehensive command and control system. The initial version of this system is being installed at the Air Force's Center for Research Support (CERES) located at the National Test Facility in Colorado Springs, Colorado. The first stage of this initiative involved the identification of commercial products capable of satisfying each functional element of a command and control system. A significant requirement in this product selection criteria was flexibility and ability to integrate with other available commercial products. This paper discusses the functions and capabilities of the product selected to provide orbit determination functions for this comprehensive command and control system.

The ILLIAC IV memory system: Current status and future possibilities

NASA Technical Reports Server (NTRS)

Stevenson, D. K.

1978-01-01

The future needs of researchers who will use the Illiac were examined and the requirements they will place on the memory system were evaluated. Various alternatives to replacing critical memory components were considered with regard to cost, risk, system impact, software requirements, and implementation schedules. The current system, its performance and status, and the limitations it places on possible enhancements are discussed as well as the planned enhancements to the Illiac processor. After a brief technology survey, different implementations are presented for each system memory component. Three different memory systems are proposed to meet the identified needs of the Illiac user community. These three alternatives differ considerably with respect to storage capacity and accessing capabilities, but they all offer significant improvements over the current system. The proposed systems and their relative merits are analyzed.

Nuclear power technology requirements for NASA exploration missions

NASA Technical Reports Server (NTRS)

Bloomfield, Harvey S.

1990-01-01

It is pointed out that future exploration of the moon and Mars will mandate developments in many areas of technology. In particular, major advances will be required in planet surface power systems. Critical nuclear technology challenges that can enable strategic self-sufficiency, acceptable operational costs, and cost-effective space transportation goals for NASA exploration missions have been identified. Critical technologies for surface power systems include stationary and mobile nuclear reactor and radioisotope heat sources coupled to static and dynamic power conversion devices. These technologies can provide dramatic reductions in mass, leading to operational and transportation cost savings. Critical technologies for space transportation systems include nuclear thermal rocket and nuclear electric propulsion options, which present compelling concepts for significantly reducing mass, cost, or travel time required for Earth-Mars transport.

Recent advances in technologies required for a "Salad Machine".

PubMed

Kliss, M; Heyenga, A G; Hoehn, A; Stodieck, L S

2000-01-01

Future long duration, manned space flight missions will require life support systems that minimize resupply requirements and ultimately approach self-sufficiency in space. Bioregenerative life support systems are a promising approach, but they are far from mature. Early in the development of the NASA Controlled Ecological Life Support System Program, the idea of onboard cultivation of salad-type vegetables for crew consumption was proposed as a first step away from the total reliance on resupply for food in space. Since that time, significant advances in space-based plant growth hardware have occurred, and considerable flight experience has been gained. This paper revisits the "Salad Machine" concept and describes recent developments in subsystem technologies for both plant root and shoot environments that are directly relevant to the development of such a facility.

Recent Advances in Technologies Required for a ``Salad Machine''

NASA Astrophysics Data System (ADS)

Kliss, M.; Heyenga, A. G.; Hoehn, A.; Stodieck, L. S.

Future long duration, manned space flight missions will require life support systems that minimize resupply requirements and ultimately approach self-sufficiency in space. Bioregenerative life support systems are a promising approach, but they are far from mature. Early in the development of the NASA Controlled Ecological Life Support System Program, the idea of onboard cultivation of salad-type vegetables for crew consumption was proposed as a first step away from the total reliance on resupply for food in space. Since that time, significant advances in space-based plant growth hardware have occurred, and considerable flight experience has been gained. This paper revisits the ``Salad Machine'' concept and describes recent developments in subsystem technologies for both plant root and shoot environments that are directly relevant to the development of such a facility

Large-Scale Cryogenic Testing of Launch Vehicle Ground Systems at the Kennedy Space Center

NASA Technical Reports Server (NTRS)

Ernst, E. W.; Sass, J. P.; Lobemeyer, D. A.; Sojourner, S. J.; Hatfield, W. H.; Rewinkel, D. A.

2007-01-01

The development of a new launch vehicle to support NASA's future exploration plans requires significant redesign and upgrade of Kennedy Space Center's (KSC) launch pad and ground support equipment systems. In many cases, specialized test equipment and systems will be required to certify the function of the new system designs under simulated operational conditions, including propellant loading. This paper provides an overview of the cryogenic test infrastructure that is in place at KSC to conduct development and qualification testing that ranges from the component level to the integrated-system level. An overview of the major cryogenic test facilities will be provided, along with a detailed explanation of the technology focus area for each facility

Closed-ecology life support systems /CELSS/ for long-duration, manned missions

NASA Technical Reports Server (NTRS)

Modell, M.; Spurlock, J. M.

1979-01-01

Studies were conducted to scope the principal areas of technology that can contribute to the development of closed-ecology life support systems (CELSS). Such systems may be required for future space activities, such as space stations, manufacturing facilities, or colonies. A major feature of CELSS is the regeneration of food from carbon in waste materials. Several processes, using biological and/or physico-chemical components, have been postulated for closing the recycle loop. At the present time, limits of available technical information preclude the specification of an optimum scheme. Nevertheless, the most significant technical requirements can be determined by way of an iterative procedure of formulating, evaluating and comparing various closed-system scenario. The functions features and applications of this systems engineering procedure are discussed.

Suitability of representative electrochemical energy storage technologies for ramp-rate control of photovoltaic power

NASA Astrophysics Data System (ADS)

Jiang, Yu; Fletcher, John; Burr, Patrick; Hall, Charles; Zheng, Bowen; Wang, Da-Wei; Ouyang, Zi; Lennon, Alison

2018-04-01

Photovoltaic (PV) systems can exhibit rapid variances in their power output due to irradiance changes which can destabilise an electricity grid. This paper presents a quantitative comparison of the suitability of different electrochemical energy storage system (ESS) technologies to provide ramp-rate control of power in PV systems. Our investigations show that, for PV systems ranging from residential rooftop systems to megawatt power systems, lithium-ion batteries with high energy densities (up to 600 Wh L-1) require the smallest power-normalised volumes to achieve the ramp rate limit of 10% min-1 with 100% compliance. As the system size increases, the ESS power-normalised volume requirements are significantly reduced due to aggregated power smoothing, with high power lithium-ion batteries becoming increasingly more favourable with increased PV system size. The possibility of module-level ramp-rate control is also introduced, and results show that achievement of a ramp rate of 10% min-1 with 100% compliance with typical junction box sizes will require ESS energy and power densities of 400 Wh L-1 and 2300 W L-1, respectively. While module-level ramp-rate control can reduce the impact of solar intermittence, the requirement is challenging, especially given the need for low cost and long cycle life.

Requirements for a mobile communications satellite system. Volume 3: Large space structures measurements study

NASA Technical Reports Server (NTRS)

Akle, W.

1983-01-01

This study report defines a set of tests and measurements required to characterize the performance of a Large Space System (LSS), and to scale this data to other LSS satellites. Requirements from the Mobile Communication Satellite (MSAT) configurations derived in the parent study were used. MSAT utilizes a large, mesh deployable antenna, and encompasses a significant range of LSS technology issues in the areas of structural/dynamics, control, and performance predictability. In this study, performance requirements were developed for the antenna. Special emphasis was placed on antenna surface accuracy, and pointing stability. Instrumentation and measurement systems, applicable to LSS, were selected from existing or on-going technology developments. Laser ranging and angulation systems, presently in breadboard status, form the backbone of the measurements. Following this, a set of ground, STS, and GEO-operational were investigated. A third scale (15 meter) antenna system as selected for ground characterization followed by STS flight technology development. This selection ensures analytical scaling from ground-to-orbit, and size scaling. Other benefits are cost and ability to perform reasonable ground tests. Detail costing of the various tests and measurement systems were derived and are included in the report.

Improved Traceability of a Small Satellite Mission Concept to Requirements Using Model Based System Engineering

NASA Technical Reports Server (NTRS)

Reil, Robin L.

2014-01-01

Model Based Systems Engineering (MBSE) has recently been gaining significant support as a means to improve the "traditional" document-based systems engineering (DBSE) approach to engineering complex systems. In the spacecraft design domain, there are many perceived and propose benefits of an MBSE approach, but little analysis has been presented to determine the tangible benefits of such an approach (e.g. time and cost saved, increased product quality). This paper presents direct examples of how developing a small satellite system model can improve traceability of the mission concept to its requirements. A comparison of the processes and approaches for MBSE and DBSE is made using the NASA Ames Research Center SporeSat CubeSat mission as a case study. A model of the SporeSat mission is built using the Systems Modeling Language standard and No Magic's MagicDraw modeling tool. The model incorporates mission concept and requirement information from the mission's original DBSE design efforts. Active dependency relationships are modeled to demonstrate the completeness and consistency of the requirements to the mission concept. Anecdotal information and process-duration metrics are presented for both the MBSE and original DBSE design efforts of SporeSat.

Improved Traceability of Mission Concept to Requirements Using Model Based Systems Engineering

NASA Technical Reports Server (NTRS)

Reil, Robin

2014-01-01

Model Based Systems Engineering (MBSE) has recently been gaining significant support as a means to improve the traditional document-based systems engineering (DBSE) approach to engineering complex systems. In the spacecraft design domain, there are many perceived and propose benefits of an MBSE approach, but little analysis has been presented to determine the tangible benefits of such an approach (e.g. time and cost saved, increased product quality). This thesis presents direct examples of how developing a small satellite system model can improve traceability of the mission concept to its requirements. A comparison of the processes and approaches for MBSE and DBSE is made using the NASA Ames Research Center SporeSat CubeSat mission as a case study. A model of the SporeSat mission is built using the Systems Modeling Language standard and No Magics MagicDraw modeling tool. The model incorporates mission concept and requirement information from the missions original DBSE design efforts. Active dependency relationships are modeled to analyze the completeness and consistency of the requirements to the mission concept. Overall experience and methodology are presented for both the MBSE and original DBSE design efforts of SporeSat.

To what extent have relaxed eligibility requirements and increased generosity of disability benefits acted as disincentives for employment? A systematic review of evidence from countries with well-developed welfare systems.

PubMed

Barr, Ben; Clayton, Stephen; Whitehead, Margaret; Thielen, Karsten; Burström, Bo; Nylén, Lotta; Dahl, Espen

2010-12-01

Reductions in the eligibility requirements and generosity of disability benefits have been introduced in several Organisation for Economic Cooperation and Development (OECD) countries in recent years, on the assumption that this will increase work incentives for people with chronic illness and disabilities. This paper systematically reviews the evidence for this assumption in the context of well-developed welfare systems. Systematic review of all empirical studies from five OECD countries from 1970 to December 2009 investigating the effect of changes in eligibility requirements or level of disability benefits on employment of disabled people. Sixteen studies were identified. Only one of five studies found that relaxed eligibility was significantly associated with a decline in employment. The most robust study found no significant effect. On generosity, eight out of 11 studies reported that benefit levels had a significant negative association with employment. The most robust study demonstrated a small but significant negative association. There was no firm evidence that changes in benefit eligibility requirements affected employment. While there was some evidence indicating that benefit level was negatively associated with employment, there was insufficient evidence of a high enough quality to determine the extent of that effect. Policy makers and researchers need to address the lack of a robust empirical basis for assessing the employment impact of these welfare reforms as well as potentially wider poverty impacts.

The Apollo Expericence Lessons Learned for Constellation Lunar Dust Management

NASA Astrophysics Data System (ADS)

Wagner, Sandra

2006-09-01

Lunar dust will present significant challenges to NASA's Lunar Exploration Missions. The challenges can be overcome by using best practices in system engineering design. For successful lunar surface missions, all systems that come into contact with lunar dust must consider the effects throughout the entire design process. Interfaces between all these systems with other systems also must be considered. Incorporating dust management into Concept of Operations and Requirements development are the best place to begin to mitigate the risks presented by lunar dust. However, that is only the beginning. To be successful, every person who works on NASA's Constellation lunar missions must be mindful of this problem. Success will also require fiscal responsibility. NASA must learn from Apollo the root cause of problems caused by dust, and then find the most cost-effective solutions to address each challenge. This will require a combination of common sense existing technologies and promising, innovative technical solutions

The Apollo Experience Lessons Learned for Constellation Lunar Dust Management

NASA Technical Reports Server (NTRS)

Wagner, Sandra

2006-01-01

Lunar dust will present significant challenges to NASA's Lunar Exploration Missions. The challenges can be overcome by using best practices in system engineering design. For successful lunar surface missions, all systems that come into contact with lunar dust must consider the effects throughout the entire design process. Interfaces between all these systems with other systems also must be considered. Incorporating dust management into Concept of Operations and Requirements development are the best place to begin to mitigate the risks presented by lunar dust. However, that is only the beginning. To be successful, every person who works on NASA's Constellation lunar missions must be mindful of this problem. Success will also require fiscal responsibility. NASA must learn from Apollo the root cause of problems caused by dust, and then find the most cost-effective solutions to address each challenge. This will require a combination of common sense existing technologies and promising, innovative technical solutions

Man-machine interface and control of the shuttle digital flight system

NASA Technical Reports Server (NTRS)

Burghduff, R. D.; Lewis, J. L., Jr.

1985-01-01

The space shuttle main engine (SSME) presented new requirements in the design of controls for large pump fed liquid rocket engine systems. These requirements were the need for built in full mission support capability, and complexity and flexibility of function not previously needed in this type of application. An engine mounted programmable digital control system was developed to meet these requirements. The engine system and controller and their function are described. Design challenges encountered during the course of development included accommodation for a very severe engine environment, the implementation of redundancy and redundancy management to provide fail operational/fail safe capability, removal of heat from the package, and significant constraints on computer memory size and processing time. The flexibility offered by programmable control reshaped the approach to engine design and development and set the pattern for future controls development in these types of applications.

Future NTP Development Synergy Leveraged from Current J-2X Engine Development

NASA Astrophysics Data System (ADS)

Ballard, Richard O.

2008-01-01

This paper is a discussion of how the many long-lead development elements required for the realization of a future nuclear thermal propulsion (NTP) system can be effectively leveraged from the ongoing work being conducted on the J-2X engine program for the Constellation Program. Development studies conducted to date for NTP forward planning have identified a number of technical areas that will require advancement to acceptable technology readiness levels (TRLs) before they can be utilized in NTP system development. These include high-temperature, high-area ratio nozzle extension; long-life, low-NPSP turbomachinery; and low-boiloff propellant management, and a qualified nuclear fuel element. The current J-2X program is working many of these areas that can be leveraged to support NTP development in a highly compatible and synergistic fashion. In addition to supporting technical development, there are other programmatic issues being worked in the J-2X program that can be leveraged by a future NTP development program. These include compliance with recently-evolved space system requirements such as human-rating, fault tolerance and fracture control. These and other similar mandatory system requirements have been adopted by NASA and can result in a significant technical impact beyond elevation of the root technologies required by NTP. Finally, the exploitation of experience, methodologies, and procedures developed by the J-2X program in the areas of verification, qualification, certification, altitude simulation testing, and facility definition will be especially applicable to a future NTP system. The similarities in system mission (in-space propulsion) and operational environment (vacuum, zero-gee) between J-2X and NTP make this highly synergistic. Thus, it can be shown that the collective benefit of leveraging experience and technologies developed during the J-2X program can result in significant savings in development cost and schedule for NTP.

Future NTP Development Synergy Leveraged from Current J-2X Engine Development

NASA Technical Reports Server (NTRS)

Ballard, Richard O.

2008-01-01

This paper is a discussion of how the many long-lead development elements required for the realization of a future nuclear thermal propulsion (NTP) system can be effectively leveraged from the ongoing work being conducted on the J-2X engine program for the Constellation Program. Development studies conducted to date for NTP forward planning have identified a number of technical areas that will require advancement to acceptable technology readiness levels (TRLs) before they can be utilized in NTP system development. These include high-temperature, high-area ratio nozzle extension; long-life, low-NPSP. turbomachinery; and low-boiloff propellant management; and a qualified nuclear fuel element. The current J-2X program is working many of these areas that can be leveraged to support NTP development in a highly compatible and synergistic fashion. In addition to supporting technical development, there are other programmatic issues being worked in the J-2X program that can be leveraged by a future NTP development program. These include compliance with recently-evolved space system requirements such as human-rating, fault tolerance and fracture control. These and other similar mandatory system requirements have been adopted by NASA and can result in a significant technical impact beyond elevation of the root technologies required by NTP. Finally, the exploitation of experience, methodologies, and procedures developed by the J-2X program in the areas of verification, qualification, certification, altitude simulation testing, and facility definition will be especially applicable to a future NTP system. The similarities in system mission (in-space propulsion) and operational environment (vacuum, zero-gee) between J-2X and NTP make this highly synergistic. Thus, it can be $hown that the collective benefit of leveraging experience and technologies developed during the J-2X program can result in significant savings in development cost and schedule for NTP.

Bicarbonate trigger for inducing lipid accumulation in algal systems

DOEpatents

Gardner, Robert; Peyton, Brent; Cooksey, Keith E.

2015-08-04

The present invention provides bicarbonate containing and/or bicarbonate-producing compositions and methods to induce lipid accumulation in an algae growth system, wherein the algae growth system is under light-dark cycling condition. By adding said compositions at a specific growth stage, said methods lead to much higher lipid accumulation and/or significantly reduced total time required for accumulating lipid in the algae growth system.

Development of Traction Drive Motors for the Toyota Hybrid System

NASA Astrophysics Data System (ADS)

Kamiya, Munehiro

Toyota Motor Corporation developed in 2005 a new hybrid system for a large SUV. This system included the new development of a high-speed traction drive motor achieving a significant increase in power weight ratio. This paper provides an overview of the hybrid system, discusses the characteristics required of a traction drive motor, and presents the technologies employed in the developed motor.

Imaginable Technologies for Human Missions to Mars

NASA Technical Reports Server (NTRS)

Bushnell, Dennis M.

2007-01-01

The thesis of the present discussion is that the simultaneous cost and inherent safety issues of human on-site exploration of Mars will require advanced-to-revolutionary technologies. The major crew safety issues as currently identified include reduced gravity, radiation, potentially extremely toxic dust and the requisite reliability for years-long missions. Additionally, this discussion examines various technological areas which could significantly impact Human-Mars cost and safety. Cost reductions for space access is a major metric, including approaches to significantly reduce the overall up-mass. Besides fuel, propulsion and power systems, the up-mass consists of the infrastructure and supplies required to keep humans healthy and the equipment for executing exploration mission tasks. Hence, the major technological areas of interest for potential cost reductions include propulsion, in-space and on-planet power, life support systems, materials and overall architecture, systems, and systems-of-systems approaches. This discussion is specifically offered in response to and as a contribution to goal 3 of the Presidential Exploration Vision: "Develop the Innovative Technologies Knowledge and Infrastructures both to explore and to support decisions about the destinations for human exploration".

Effects of dietary methionine on performance, egg quality and glutathione redox system in egg-laying ducks.

PubMed

Fouad, A M; Ruan, D; Lin, Y C; Zheng, C T; Zhang, H X; Chen, W; Wang, S; Xia, W G; Li, Y

2016-12-01

In this study, 6 dietary DL-methionine (Met) levels (2.5, 3.0, 3.5, 4.0, 4.5 and 5.0 g/kg) were tested to estimate the dietary Met requirements of Longyan ducks from 19 to 46 weeks of age, and to investigate its effect on the glutathione redox system. In total, 1080 Longyan ducks aged 19 weeks were allocated randomly to the 6 dietary treatments, where each treatment comprised 6 replicate pens with 30 ducks per pen. Met had no effects on egg production, yolk weight, yolk colour or the glutathione redox system, but the egg weight, egg mass and feed conversion ratio (FCR) were improved significantly by dietary Met supplementation. As the dietary Met concentration increased, the eggshell thickness and breaking strength decreased significantly, whereas the albumen weight increased significantly. According to broken-line regression analysis, the optimum Met requirements for egg weight, egg mass, FCR and albumen weight are 686, 661, 658 and 731 mg/bird/d, respectively, with a dietary crude protein level of 170 g/kg.

7 CFR 1730.21 - Inspections and tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... reliability and security of the electric power grid, cause significant risk to the safety and health of the... AGRICULTURE ELECTRIC SYSTEM OPERATIONS AND MAINTENANCE Operations and Maintenance Requirements § 1730.21... parts of its electric system, annually exercise its ERP, and maintain records of such inspections and...

Issues and status of power distribution options for space exploration

NASA Technical Reports Server (NTRS)

Bercaw, Robert W.; Cull, Ronald C.; Kenny, Barbara H.

1991-01-01

The Space Exploration Initiative (SEI) will need a wide variety of manned systems with requirements significantly different than those for existing systems. The concept of a space power utility is discussed and the impact of this concept on the engineering of space power systems is examined. Almost all existing space power systems use low voltage direct current. Although they have been very succesful, increasing power system requirements in recent years have exposed their inherent limitations and led to the proposal of a number of alternatives including high voltage DC and AC at various frequencies. Drawing on the experience gained from Space Station Freedom and SEI systems studies, factors that may affect the choice of frequency standards on which to build such a space power utility are discussed.

Computer model for characterizing, screening, and optimizing electrolyte systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gering, Kevin L.

2015-06-15

Electrolyte systems in contemporary batteries are tasked with operating under increasing performance requirements. All battery operation is in some way tied to the electrolyte and how it interacts with various regions within the cell environment. Seeing the electrolyte plays a crucial role in battery performance and longevity, it is imperative that accurate, physics-based models be developed that will characterize key electrolyte properties while keeping pace with the increasing complexity of these liquid systems. Advanced models are needed since laboratory measurements require significant resources to carry out for even a modest experimental matrix. The Advanced Electrolyte Model (AEM) developed at themore » INL is a proven capability designed to explore molecular-to-macroscale level aspects of electrolyte behavior, and can be used to drastically reduce the time required to characterize and optimize electrolytes. Although it is applied most frequently to lithium-ion battery systems, it is general in its theory and can be used toward numerous other targets and intended applications. This capability is unique, powerful, relevant to present and future electrolyte development, and without peer. It redefines electrolyte modeling for highly-complex contemporary systems, wherein significant steps have been taken to capture the reality of electrolyte behavior in the electrochemical cell environment. This capability can have a very positive impact on accelerating domestic battery development to support aggressive vehicle and energy goals in the 21st century.« less

Absence of significant dissent should be sufficient for deceased donor organ procurement in New Zealand.

PubMed

Douglas, Thomas M; Douglas, Nicholas M

2009-10-01

New Zealand's organ donation rates are among the lowest in the OECD. In a bid to increase organ availability, the New Zealand Human Tissue Act 2008 introduces new consent arrangements for deceased donor organ procurement. This article assesses these new arrangements and presents the case for further reform. Our assessment and arguments are based on philosophical analysis informed by empirical data on the effectiveness of alternative consent systems. We: 1) Identify widely held ethical judgments about policies and practices relevant to organ donation (e.g. those relating to coronial post-mortems), 2) Assess the implications of these judgments for the Human Tissue Act and the assumptions that underpin it, and 3) Derive policy recommendations that are consistent with the judgments. The Human Tissue Act 2008 retains a strong consent requirement for organ procurement: organs may not be transplanted unless either the deceased or the family consents. We argue that organ availability could and should be increased by shifting from a model that requires consent to one that requires the absence of significant dissent. We recommend that New Zealand adopt either 1) an organ donation system similar to the existing system for ordering coronial post-mortems, or 2) a variant of the 'opt-out' system already in place in several other countries.

Defining quality for distal pancreatectomy: does the laparoscopic approach protect patients from poor quality outcomes?

PubMed

Baker, Marshall S; Sherman, Karen L; Stocker, Susan; Hayman, Amanda V; Bentrem, David J; Prinz, Richard A; Talamonti, Mark S

2013-02-01

Established systems for grading postoperative complications do not change the assigned grade when multiple interventions or readmissions are required to manage a complication. Studies using these systems may misrepresent outcomes for the surgical procedures being evaluated. We define a quality outcome for distal pancreatectomy (DP) and use this metric to compare laparoscopic distal pancreatectomy (LDP) to open distal pancreatectomy (ODP). Records for patients undergoing DP between January 2006 and December 2009 were reviewed. Clavien-Dindo grade IIIb, IV, and V complications were classified as severe adverse--poor quality--postoperative outcomes (SAPOs). II and IIIa complications requiring either significantly prolonged overall lengths of stay including readmissions within 90 days or more than one invasive intervention were also classified as SAPOs. By Clavien-Dindo system alone, 91 % of DP patients had either no complication or a low/moderate grade (I, II, IIIa) complication. Using our reclassification, however, 25 % had a SAPO. Patients undergoing LDP demonstrated a Clavien-Dindo complication profile identical to that for SDP but demonstrated significantly shorter overall lengths of stay, were less likely to require perioperative transfusion, and less likely to have a SAPO. Established systems undergrade the severity of some complications following DP. Using a procedure-specific metric for quality, we demonstrate that LDP affords a higher quality postoperative outcome than ODP.

Efficacy of Various Scoring Systems for Predicting the 28-Day Survival Rate among Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease Requiring Emergency Intensive Care.

PubMed

Feng, Zhihong; Wang, Tao; Liu, Ping; Chen, Sipeng; Xiao, Han; Xia, Ning; Luo, Zhiming; Wei, Bing; Nie, Xiuhong

2017-01-01

We aimed to investigate the efficacy of four severity-of-disease scoring systems in predicting the 28-day survival rate among patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) requiring emergency care. Clinical data of patients with AECOPD who required emergency care were recorded over 2 years. APACHE II, SAPS II, SOFA, and MEDS scores were calculated from severity-of-disease indicators recorded at admission and compared between patients who died within 28 days of admission (death group; 46 patients) and those who did not (survival group; 336 patients). Compared to the survival group, the death group had a significantly higher GCS score, frequency of comorbidities including hypertension and heart failure, and age ( P < 0.05 for all). With all four systems, scores of age, gender, renal inadequacy, hypertension, coronary heart disease, heart failure, arrhythmia, anemia, fracture leading to bedridden status, tumor, and the GCS were significantly higher in the death group than the survival group. The prediction efficacy of the APACHE II and SAPS II scores was 88.4%. The survival rates did not differ significantly between APACHE II and SAPS II ( P = 1.519). Our results may guide triage for early identification of critically ill patients with AECOPD in the emergency department.

Design of the polar neutron-imaging aperture for use at the National Ignition Facility.

PubMed

Fatherley, V E; Barker, D A; Fittinghoff, D N; Hibbard, R L; Martinez, J I; Merrill, F E; Oertel, J A; Schmidt, D W; Volegov, P L; Wilde, C H

2016-11-01

The installation of a neutron imaging diagnostic with a polar view at the National Ignition Facility (NIF) required design of a new aperture, an extended pinhole array (PHA). This PHA is different from the pinhole array for the existing equatorial system due to significant changes in the alignment and recording systems. The complex set of component requirements, as well as significant space constraints in its intended location, makes the design of this aperture challenging. In addition, lessons learned from development of prior apertures mandate careful aperture metrology prior to first use. This paper discusses the PHA requirements, constraints, and the final design. The PHA design is complex due to size constraints, machining precision, assembly tolerances, and design requirements. When fully assembled, the aperture is a 15 mm × 15 mm × 200 mm tungsten and gold assembly. The PHA body is made from 2 layers of tungsten and 11 layers of gold. The gold layers include 4 layers containing penumbral openings, 4 layers containing pinholes and 3 spacer layers. In total, there are 64 individual, triangular pinholes with a field of view (FOV) of 200 μm and 6 penumbral apertures. Each pinhole is pointed to a slightly different location in the target plane, making the effective FOV of this PHA a 700 μm square in the target plane. The large FOV of the PHA reduces the alignment requirements both for the PHA and the target, allowing for alignment with a laser tracking system at NIF.

40 CFR 141.708 - Requirements when making a significant change in disinfection practice.

Code of Federal Regulations, 2014 CFR

2014-07-01

... source water monitoring under § 141.701(a), a system that plans to make a significant change to its... change in disinfection practice. 141.708 Section 141.708 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced...

40 CFR 141.708 - Requirements when making a significant change in disinfection practice.

Code of Federal Regulations, 2011 CFR

2011-07-01

... source water monitoring under § 141.701(a), a system that plans to make a significant change to its... change in disinfection practice. 141.708 Section 141.708 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced...

40 CFR 141.708 - Requirements when making a significant change in disinfection practice.

Code of Federal Regulations, 2012 CFR

2012-07-01

... source water monitoring under § 141.701(a), a system that plans to make a significant change to its... change in disinfection practice. 141.708 Section 141.708 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced...

40 CFR 141.708 - Requirements when making a significant change in disinfection practice.

Code of Federal Regulations, 2013 CFR

2013-07-01

... source water monitoring under § 141.701(a), a system that plans to make a significant change to its... change in disinfection practice. 141.708 Section 141.708 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced...

Flywheel energy storage for electromechanical actuation systems

NASA Technical Reports Server (NTRS)

Hockney, Richard L.; Goldie, James H.; Kirtley, James L.

1991-01-01

The authors describe a flywheel energy storage system designed specifically to provide load-leveling for a thrust vector control (TVC) system using electromechanical actuators (EMAs). One of the major advantages of an EMA system over a hydraulic system is the significant reduction in total energy consumed during the launch profile. Realization of this energy reduction will, however, require localized energy storage capable of delivering the peak power required by the EMAs. A combined flywheel-motor/generator unit which interfaces directly to the 20-kHz power bus represents an ideal candidate for this load leveling. The overall objective is the definition of a flywheel energy storage system for this application. The authors discuss progress on four technical objectives: (1) definition of the specifications for the flywheel-motor/generator system, including system-level trade-off analysis; (2) design of the flywheel rotor; (3) design of the motor/generator; and (4) determination of the configuration for the power management system.

Flywheel energy storage for electromechanical actuation systems

NASA Astrophysics Data System (ADS)

Hockney, Richard L.; Goldie, James H.; Kirtley, James L.

The authors describe a flywheel energy storage system designed specifically to provide load-leveling for a thrust vector control (TVC) system using electromechanical actuators (EMAs). One of the major advantages of an EMA system over a hydraulic system is the significant reduction in total energy consumed during the launch profile. Realization of this energy reduction will, however, require localized energy storage capable of delivering the peak power required by the EMAs. A combined flywheel-motor/generator unit which interfaces directly to the 20-kHz power bus represents an ideal candidate for this load leveling. The overall objective is the definition of a flywheel energy storage system for this application. The authors discuss progress on four technical objectives: (1) definition of the specifications for the flywheel-motor/generator system, including system-level trade-off analysis; (2) design of the flywheel rotor; (3) design of the motor/generator; and (4) determination of the configuration for the power management system.

Extending the life and recycle capability of earth storable propellant systems.

NASA Technical Reports Server (NTRS)

Schweickert, T. F.

1972-01-01

Rocket propulsion systems for reusable vehicles will be required to operate reliably for a large number of missions with a minimum of maintenance and a fast turnaround. For the space shuttle reaction control system to meet these requirements, current and prior related system failures were examined for their impact on reuse and, where warranted, component design and/or system configuration changes were defined for improving system service life. It was found necessary to change the pressurization component arrangement used on many single-use applications in order to eliminate a prevalent check valve failure mode and to incorporate redundant expulsion capability in propellant tank designs to achieve the necessary system reliability. Material flaws in pressurant and propellant tanks were noted to have a significant effect on tank cycle life. Finally, maintenance considerations dictated a modularized systems approach, allowing the system to be removed from the vehicle for service and repair at a remote site.

Power system characteristics for more electric aircraft

NASA Technical Reports Server (NTRS)

Hansen, Irving G.

1993-01-01

It should not be suprising that more electric aircraft must meet significantly more difficult electrical power system requirements than were considereed when today's power distribution systems were being developed. Electric power, no longer a secondary system, will become a critical element of the primary control system. Functional reliability requiirements will be extremely stringent and can only be met by controlling element redundancy within a distributed power system. Existing electrical systems were not developed to have both the power system and the control/sensing elements distributed and yet meet the requirements of lighting tolerance and high intensity radio frequency (HIRF). In addition, the operation of electric actuators involves high transient loading and reverse energy flows. Such phenomena were also not anticipated when power quality was specified for either 270 vdc or 400 Hertz ac power systems. This paper will expand upon the issues and discuss some of the technologies involved in their resolution.

Design of investment management optimization system for power grid companies under new electricity reform

NASA Astrophysics Data System (ADS)

Yang, Chunhui; Su, Zhixiong; Wang, Xin; Liu, Yang; Qi, Yongwei

2017-03-01

The new normalization of the economic situation and the implementation of a new round of electric power system reform put forward higher requirements to the daily operation of power grid companies. As an important day-to-day operation of power grid companies, investment management is directly related to the promotion of the company's operating efficiency and management level. In this context, the establishment of power grid company investment management optimization system will help to improve the level of investment management and control the company, which is of great significance for power gird companies to adapt to market environment changing as soon as possible and meet the policy environment requirements. Therefore, the purpose of this paper is to construct the investment management optimization system of power grid companies, which includes investment management system, investment process control system, investment structure optimization system, and investment project evaluation system and investment management information platform support system.

Evaluation of Vasopressin for Septic Shock in Patients on Chronic Renin-Angiotensin-Aldosterone System Inhibitors.

PubMed

Erwin, Beth L; Denaburg, Michael A; Barker, Andrew B; McArdle, Philip J; Windham, Samuel T; Morgan, Charity J

2017-12-01

To compare the hemodynamic response in septic shock patients receiving vasopressin who were on chronic renin-angiotensin-aldosterone system inhibitor therapy with those who were not. Single-center, retrospective cohort study. Medical and surgical ICUs at a 1,100-bed academic medical center. Medical and surgical ICU patients with septic shock who received vasopressin infusion added to at least one concomitant vasopressor agent between January 2014 and December 2015, then divided into two cohorts: 1) patients who were on chronic renin-angiotensin-aldosterone system inhibitor therapy as outpatients and 2) patients who were not on chronic renin-angiotensin-aldosterone system inhibitor therapy as outpatients. None. Mean arterial pressure at 6 hours was 72.2 mm Hg in the renin-angiotensin-aldosterone system inhibitor group versus 69.7 mm Hg in the non-renin-angiotensin-aldosterone system inhibitor group (p = 0.298). There was no difference in mean arterial pressure at 1, 24, or 48 hours between groups. Total concomitant vasopressor requirements, based on norepinephrine equivalents excluding vasopressin, were significantly lower at 24 hours in the renin-angiotensin-aldosterone system inhibitor group versus the non-renin-angiotensin-aldosterone system inhibitor group (10.7 vs 18.1 µg/min, respectively; p = 0.007), but no significant differences were seen at the other time points assessed. There were no significant differences in ICU or hospital length of stay or mortality. There was no significant difference in the primary outcome of 6-hour mean arterial pressure in septic shock patients receiving vasopressin who were on chronic renin-angiotensin-aldosterone system inhibitor therapy versus those receiving vasopressin who were not on chronic renin-angiotensin-aldosterone system inhibitor therapy. Renin-angiotensin-aldosterone system inhibitor patients had lower total concomitant vasopressor requirements at 24 hours compared with non-renin-angiotensin-aldosterone system inhibitor patients.

Development, Demonstration, and Analysis of an Integrated Iodine Hall Thruster Feed System

NASA Technical Reports Server (NTRS)

Polzin, Kurt A.; Peeples, Steven R.; Burt, Adam O.; Martin, Adam K.; Martinez, Armando; Seixal, Joao F.; Mauro, Stephanie

2016-01-01

The design of an in-space iodine-vapor-fed Hall effect thruster propellant management system is described. The solid-iodine propellant tank has unique issues associated with the microgravity environment, requiring a solution where the iodine is maintained in intimate thermal contact with the heated tank walls. The flow control valves required alterations from earlier iterations to survive for extended periods of time in the corrosive iodine-vapor environment. Materials have been selected for the entire feed system that can chemically resist the iodine vapor, with the design now featuring Hastelloy or Inconel for almost all the wetted components. An integrated iodine feed system/Hall thruster demonstration unit was fabricated and tested, with all control being handled by an onboard electronics card specifically designed to operate the feed system. Structural analysis shows that the feed system can survive launch loads after the implementation of some minor reinforcement. Flow modeling, while still requiring significant additional validation, is presented to show its potential in capturing the behavior of components in this low-flow, low-pressure system.

Climate change induced transformations of agricultural systems: insights from a global model

NASA Astrophysics Data System (ADS)

Leclère, D.; Havlík, P.; Fuss, S.; Schmid, E.; Mosnier, A.; Walsh, B.; Valin, H.; Herrero, M.; Khabarov, N.; Obersteiner, M.

2014-12-01

Climate change might impact crop yields considerably and anticipated transformations of agricultural systems are needed in the coming decades to sustain affordable food provision. However, decision-making on transformational shifts in agricultural systems is plagued by uncertainties concerning the nature and geography of climate change, its impacts, and adequate responses. Locking agricultural systems into inadequate transformations costly to adjust is a significant risk and this acts as an incentive to delay action. It is crucial to gain insight into how much transformation is required from agricultural systems, how robust such strategies are, and how we can defuse the associated challenge for decision-making. While implementing a definition related to large changes in resource use into a global impact assessment modelling framework, we find transformational adaptations to be required of agricultural systems in most regions by 2050s in order to cope with climate change. However, these transformations widely differ across climate change scenarios: uncertainties in large-scale development of irrigation span in all continents from 2030s on, and affect two-thirds of regions by 2050s. Meanwhile, significant but uncertain reduction of major agricultural areas affects the Northern Hemisphere’s temperate latitudes, while increases to non-agricultural zones could be large but uncertain in one-third of regions. To help reducing the associated challenge for decision-making, we propose a methodology exploring which, when, where and why transformations could be required and uncertain, by means of scenario analysis.

Heroic Reliability Improvement in Manned Space Systems

NASA Technical Reports Server (NTRS)

Jones, Harry W.

2017-01-01

System reliability can be significantly improved by a strong continued effort to identify and remove all the causes of actual failures. Newly designed systems often have unexpected high failure rates which can be reduced by successive design improvements until the final operational system has an acceptable failure rate. There are many causes of failures and many ways to remove them. New systems may have poor specifications, design errors, or mistaken operations concepts. Correcting unexpected problems as they occur can produce large early gains in reliability. Improved technology in materials, components, and design approaches can increase reliability. The reliability growth is achieved by repeatedly operating the system until it fails, identifying the failure cause, and fixing the problem. The failure rate reduction that can be obtained depends on the number and the failure rates of the correctable failures. Under the strong assumption that the failure causes can be removed, the decline in overall failure rate can be predicted. If a failure occurs at the rate of lambda per unit time, the expected time before the failure occurs and can be corrected is 1/lambda, the Mean Time Before Failure (MTBF). Finding and fixing a less frequent failure with the rate of lambda/2 per unit time requires twice as long, time of 1/(2 lambda). Cutting the failure rate in half requires doubling the test and redesign time and finding and eliminating the failure causes.Reducing the failure rate significantly requires a heroic reliability improvement effort.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stewart, John; Halbgewachs, Ron; Chavez, Adrian

The manner in which the control systems are being designed and operated in the energy sector is undergoing some of the most significant changes in history due to the evolution of technology and the increasing number of interconnections to other system. With these changes however come two significant challenges that the energy sector must face; 1) Cyber security is more important than ever before, and 2) Cyber security is more complicated than ever before. A key requirement in helping utilities and vendors alike in meeting these challenges is interoperability. While interoperability has been present in much of the discussions relatingmore » to technology utilized within the energy sector and especially the Smart Grid, it has been absent in the context of cyber security. The Lemnos project addresses these challenges by focusing on the interoperability of devices utilized within utility control systems which support critical cyber security functions. In theory, interoperability is possible with many of the cyber security solutions available to utilities today. The reality is that the effort required to achieve cyber security interoperability is often a barrier for utilities. For example, consider IPSec, a widely-used Internet Protocol to define Virtual Private Networks, or tunnels , to communicate securely through untrusted public and private networks. The IPSec protocol suite has a significant number of configuration options and encryption parameters to choose from, which must be agreed upon and adopted by both parties establishing the tunnel. The exercise in getting software or devices from different vendors to interoperate is labor intensive and requires a significant amount of security expertise by the end user. Scale this effort to a significant number of devices operating over a large geographical area and the challenge becomes so overwhelming that it often leads utilities to pursue solutions from a single vendor. These single vendor solutions may inadvertently lock utilities into proprietary and closed systems.« less

Design and Analysis of a Flexible, Reliable Deep Space Life Support System

NASA Technical Reports Server (NTRS)

Jones, Harry W.

2012-01-01

This report describes a flexible, reliable, deep space life support system design approach that uses either storage or recycling or both together. The design goal is to provide the needed life support performance with the required ultra reliability for the minimum Equivalent System Mass (ESM). Recycling life support systems used with multiple redundancy can have sufficient reliability for deep space missions but they usually do not save mass compared to mixed storage and recycling systems. The best deep space life support system design uses water recycling with sufficient water storage to prevent loss of crew if recycling fails. Since the amount of water needed for crew survival is a small part of the total water requirement, the required amount of stored water is significantly less than the total to be consumed. Water recycling with water, oxygen, and carbon dioxide removal material storage can achieve the high reliability of full storage systems with only half the mass of full storage and with less mass than the highly redundant recycling systems needed to achieve acceptable reliability. Improved recycling systems with lower mass and higher reliability could perform better than systems using storage.

It Won't Be Easy, but You Must Learn the Arcane New Rules of Arbitrage.

ERIC Educational Resources Information Center

Anderson, David; Brennan, William

1988-01-01

With passage of the Tax Reform Act of 1986, school systems became liable to the federal government for any profits earned on tax-exempt bonds. Understanding the requirements is essential for any board facing significant capital financing. Outlines requirements, exceptions to the rule, penalties, costs, and debt planning. (MLF)

An Empirical System for Assessing the Impact of Aptitude Requirement Adjustments on Air Force Initial Skills Training.

ERIC Educational Resources Information Center

Mumford, Michael D.; And Others

A multivariate modeling approach was developed to assess the impact of changes in aptitude requirement minimums on U.S. Air Force technical training outcomes. Initially, interviews were conducted with technical training personnel to identify significant student inputs, course content, and training outcome variables. Measures of these variables…

Cost Savings Associated with the Adoption of a Cloud Computing Data Transfer System for Trauma Patients.

PubMed

Feeney, James M; Montgomery, Stephanie C; Wolf, Laura; Jayaraman, Vijay; Twohig, Michael

2016-09-01

Among transferred trauma patients, challenges with the transfer of radiographic studies include problems loading or viewing the studies at the receiving hospitals, and problems manipulating, reconstructing, or evalu- ating the transferred images. Cloud-based image transfer systems may address some ofthese problems. We reviewed the charts of patients trans- ferred during one year surrounding the adoption of a cloud computing data transfer system. We compared the rates of repeat imaging before (precloud) and af- ter (postcloud) the adoption of the cloud-based data transfer system. During the precloud period, 28 out of 100 patients required 90 repeat studies. With the cloud computing transfer system in place, three out of 134 patients required seven repeat films. There was a statistically significant decrease in the proportion of patients requiring repeat films (28% to 2.2%, P < .0001). Based on an annualized volume of 200 trauma patient transfers, the cost savings estimated using three methods of cost analysis, is between $30,272 and $192,453.

Spatiotemporal control to eliminate cardiac alternans using isostable reduction

NASA Astrophysics Data System (ADS)

Wilson, Dan; Moehlis, Jeff

2017-03-01

Cardiac alternans, an arrhythmia characterized by a beat-to-beat alternation of cardiac action potential durations, is widely believed to facilitate the transition from normal cardiac function to ventricular fibrillation and sudden cardiac death. Alternans arises due to an instability of a healthy period-1 rhythm, and most dynamical control strategies either require extensive knowledge of the cardiac system, making experimental validation difficult, or are model independent and sacrifice important information about the specific system under study. Isostable reduction provides an alternative approach, in which the response of a system to external perturbations can be used to reduce the complexity of a cardiac system, making it easier to work with from an analytical perspective while retaining many of its important features. Here, we use isostable reduction strategies to reduce the complexity of partial differential equation models of cardiac systems in order to develop energy optimal strategies for the elimination of alternans. Resulting control strategies require significantly less energy to terminate alternans than comparable strategies and do not require continuous state feedback.

Industrial WSN Based on IR-UWB and a Low-Latency MAC Protocol

NASA Astrophysics Data System (ADS)

Reinhold, Rafael; Underberg, Lisa; Wulf, Armin; Kays, Ruediger

2016-07-01

Wireless sensor networks for industrial communication require high reliability and low latency. As current wireless sensor networks do not entirely meet these requirements, novel system approaches need to be developed. Since ultra wideband communication systems seem to be a promising approach, this paper evaluates the performance of the IEEE 802.15.4 impulse-radio ultra-wideband physical layer and the IEEE 802.15.4 Low Latency Deterministic Network (LLDN) MAC for industrial applications. Novel approaches and system adaptions are proposed to meet the application requirements. In this regard, a synchronization approach based on circular average magnitude difference functions (CAMDF) and on a clean template (CT) is presented for the correlation receiver. An adapted MAC protocol titled aggregated low latency (ALL) MAC is proposed to significantly reduce the resulting latency. Based on the system proposals, a hardware prototype has been developed, which proves the feasibility of the system and visualizes the real-time performance of the MAC protocol.

ATTDES: An Expert System for Satellite Attitude Determination and Control. 2

NASA Technical Reports Server (NTRS)

Mackison, Donald L.; Gifford, Kevin

1996-01-01

The design, analysis, and flight operations of satellite attitude determintion and attitude control systems require extensive mathematical formulations, optimization studies, and computer simulation. This is best done by an analyst with extensive education and experience. The development of programs such as ATTDES permit the use of advanced techniques by those with less experience. Typical tasks include the mission analysis to select stabilization and damping schemes, attitude determination sensors and algorithms, and control system designs to meet program requirements. ATTDES is a system that includes all of these activities, including high fidelity orbit environment models that can be used for preliminary analysis, parameter selection, stabilization schemes, the development of estimators covariance analyses, and optimization, and can support ongoing orbit activities. The modification of existing simulations to model new configurations for these purposes can be an expensive, time consuming activity that becomes a pacing item in the development and operation of such new systems. The use of an integrated tool such as ATTDES significantly reduces the effort and time required for these tasks.

Fault tolerant computer control for a Maglev transportation system

NASA Technical Reports Server (NTRS)

Lala, Jaynarayan H.; Nagle, Gail A.; Anagnostopoulos, George

1994-01-01

Magnetically levitated (Maglev) vehicles operating on dedicated guideways at speeds of 500 km/hr are an emerging transportation alternative to short-haul air and high-speed rail. They have the potential to offer a service significantly more dependable than air and with less operating cost than both air and high-speed rail. Maglev transportation derives these benefits by using magnetic forces to suspend a vehicle 8 to 200 mm above the guideway. Magnetic forces are also used for propulsion and guidance. The combination of high speed, short headways, stringent ride quality requirements, and a distributed offboard propulsion system necessitates high levels of automation for the Maglev control and operation. Very high levels of safety and availability will be required for the Maglev control system. This paper describes the mission scenario, functional requirements, and dependability and performance requirements of the Maglev command, control, and communications system. A distributed hierarchical architecture consisting of vehicle on-board computers, wayside zone computers, a central computer facility, and communication links between these entities was synthesized to meet the functional and dependability requirements on the maglev. Two variations of the basic architecture are described: the Smart Vehicle Architecture (SVA) and the Zone Control Architecture (ZCA). Preliminary dependability modeling results are also presented.

Improved simulation of river water and groundwater exchange in an alluvial plain using the SWAT model

USDA-ARS?s Scientific Manuscript database

Hydrological interaction between surface and subsurface water systems has a significant impact on water quality, ecosystems and biogeochemistry cycling of both systems. Distributed models have been developed to simulate this function, but they require detailed spatial inputs and extensive computati...

The National Biofuels Strategy - Importance of sustainable feedstock production systems in regional-based supply chains

USDA-ARS?s Scientific Manuscript database

Region-based production systems are needed to produce the feedstocks that will be turned into the biofuels required to meet Federal mandated targets. Executive and Legislative actions have put into motion significant government responses designed to advance the development and production of domestic...

14 CFR 255.4 - Display of information.

Code of Federal Regulations, 2010 CFR

2010-01-01

... with the requirements of this section. (1) Each system must offer an integrated display that uses the.... (2) Each integrated display offered by a system must either use elapsed time as a significant factor in selecting service options from the database or give single-plane flights a preference over...

Advancing Technology: GPS and GIS Outreach Training for Agricultural Producers

ERIC Educational Resources Information Center

Flynn, Allison; Arnold, Shannon

2010-01-01

The use of the Global Positioning System (GPS) and Global Information Systems (GIS) has made significant impacts on agricultural production practices. However, constant changes in the technologies require continuing educational updates. The outreach program described here introduces the operation, use, and applications of GPS receivers and GIS…

10 CFR 50.36 - Technical specifications.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., or component that is part of the primary success path and which functions or actuates to mitigate a... significant safety functions. Where a limiting safety system setting is specified for a variable on which a... the automatic safety system does not function as required, the licensee shall take appropriate action...

Effects of Dynamically Weighting Autonomous Rules in an Unmanned Aircraft System (UAS) Flocking Model

DTIC Science & Technology

2014-09-18

methods of flight plan optimization, and yielded such techniques as: parallel A* (Gudaitis, 1994), Multi-Objective Traveling Salesman algorithms...1 Problem Statement...currently their utilization comes with a price: Problem Statement “Today’s unmanned systems require significant human interaction to operate. As

Effects of climate change on suitable rice cropping areas, cropping systems and crop water requirements in southern China

DOE PAGES

Ye, Qing; Yang, Xiaoguang; Dai, Shuwei; ...

2015-06-05

Here, we discuss that rice is one of the main crops grown in southern China. Global climate change has significantly altered the local water availability and temperature regime for rice production. In this study, we explored the influence of climate change on suitable rice cropping areas, rice cropping systems and crop water requirements (CWRs) during the growing season for historical (from 1951 to 2010) and future (from 2011 to 2100) time periods. The results indicated that the land areas suitable for rice cropping systems shifted northward and westward from 1951 to 2100 but with different amplitudes.

Main propulsion system test requirements for the two-engine Shuttle-C

NASA Technical Reports Server (NTRS)

Lynn, E. E.; Platt, G. K.

1989-01-01

The Shuttle-C is an unmanned cargo carrying derivative of the space shuttle with optional two or three space shuttle main engines (SSME's), whereas the shuttle has three SSME's. Design and operational differences between the Shuttle-C and shuttle were assessed to determine requirements for additional main propulsion system (MPS) verification testing. Also, reviews were made of the shuttle main propulsion test program objectives and test results and shuttle flight experience. It was concluded that, if significant MPS modifications are not made beyond those currently planned, then main propulsion system verification can be concluded with an on-pad flight readiness firing.

Overview of the Altair Lunar Lander Thermal Control System Design

NASA Technical Reports Server (NTRS)

Stephan, Ryan A.

2010-01-01

NASA's Constellation Program has been developed to successfully return humans to the Lunar surface by 2020. The Constellation Program includes several different project offices including Altair, which is the next generation Lunar Lander. The planned Altair missions are very different than the Lunar missions accomplished during the Apollo era. These differences have resulted in a significantly different thermal control system architecture. The current paper will summarize the Altair mission architecture and the various operational phases. In addition, the derived thermal requirements will be presented. The paper will conclude with a brief description of the thermal control system designed to meet these unique and challenging thermal requirements.

Extraction of pacemaker and implantable cardioverter defibrillator leads: a single-centre study of electrosurgical and laser extraction.

PubMed

Scott, Paul A; Chow, Whitney; Ellis, Elizabeth; Morgan, John M; Roberts, Paul R

2009-11-01

Both electrosurgical dissection (EDS) and laser tools are effective in the extraction of chronic implanted endovascular leads. It is unclear which is superior. We undertook a retrospective single-centre study to assess this. In our institution from 2000 to 2004, all extractions requiring an ablative sheath were performed using the EDS system. In 2004, an excimer laser system was acquired, which became the first choice. Consecutive patients undergoing extraction requiring an ablative sheath (EDS or laser) were studied. From 2000 to 2007, 140 leads were extracted from 74 patients (EDS 31 and laser 43). Procedural success was non-significantly higher in the laser vs. the EDS group (95 vs. 87%). In the EDS group, one patient suffered tamponade requiring surgery; in the laser group, one patient suffered a significant pericardial effusion treated conservatively. There were no deaths. Procedure and fluoroscopy times were similar between groups. More patients were referred for primary surgical extraction in the EDS vs. the laser era (7 vs. 0, P = 0.003). Lead extraction using an ablative sheath is safe and effective. In our small study, there were no significant differences between EDS and laser sheaths in terms of success, time, or safety.

An interfaces approach to TES ground data system processing design with the Science Investigator-led Processing System (SIPS)

NASA Technical Reports Server (NTRS)

Kurian, R.; Grifin, A.

2002-01-01

Developing production-quality software to process the large volumes of scientific data is the responsibility of the TES Ground Data System, which is being developed at the Jet Propulsion Laboratory together with support contractor Raytheon/ITSS. The large data volume and processing requirements of the TES pose significant challenges to the design.

Liquid rocket booster integration study. Volume 3: Study products. Part 2: Sections 8-19

NASA Technical Reports Server (NTRS)

1988-01-01

The impacts of introducing liquid rocket booster engines (LRB) into the Space Transportation System (STS)/Kennedy Space Center (KSC) launch environment are identified and evaluated. Proposed ground systems configurations are presented along with a launch site requirements summary. Prelaunch processing scenarios are described and the required facility modifications and new facility requirements are analyzed. Flight vehicle design recommendations to enhance launch processing are discussed. Processing approaches to integrate LRB with existing STS launch operations are evaluated. The key features and significance of launch site transition to a new STS configuration in parallel with ongoing launch activities are enumerated. This volume is part two of the study products section of the five volume series.

Liquid rocket booster integration study. Volume 3, part 1: Study products

NASA Technical Reports Server (NTRS)

1988-01-01

The impacts of introducing liquid rocket booster engines (LRB) into the Space Transportation System (STS)/Kennedy Space Center (KSC) launch environment are identified and evaluated. Proposed ground systems configurations are presented along with a launch site requirements summary. Prelaunch processing scenarios are described and the required facility modifications and new facility requirements are analyzed. Flight vehicle design recommendations to enhance launch processing are discussed. Processing approaches to integrate LRB with existing STS launch operations are evaluated. The key features and significance of launch site transition to a new STS configuration in parallel with ongoing launch activities are enumerated. This volume is part one of the study products section of the five volume series.

Capturing the Impact of Storage and Other Flexible Technologies on Electric System Planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hale, Elaine; Stoll, Brady; Mai, Trieu

Power systems of the future are likely to require additional flexibility. This has been well studied from an operational perspective, but has been more difficult to incorporate into capacity expansion models (CEMs) that study investment decisions on the decadal scale. There are two primary reasons for this. First, the necessary input data, including cost and resource projections, for flexibility options like demand response and storage are significantly uncertain. Second, it is computationally difficult to represent both investment and operational decisions in detail, the latter being necessary to properly value system flexibility, in CEMs for realistically sized systems. In this work,more » we extend a particular CEM, NREL's Resource Planning Model (RPM), to address the latter issue by better representing variable generation impacts on operations, and then adding two flexible technologies to RPM's suite of investment decisions: interruptible load and utility-scale storage. This work does not develop full suites of input data for these technologies, but is rather methodological and exploratory in nature. We thus exercise these new investment decisions in the context of exploring price points and value streams needed for significant deployment in the Western Interconnection by 2030. Our study of interruptible load finds significant variation by location, year, and overall system conditions. Some locations find no system need for interruptible load even with low costs, while others build the most expensive resources offered. System needs can include planning reserve capacity needs to ensure resource adequacy, but there are also particular cases in which spinning reserve requirements drive deployment. Utility-scale storage is found to require deep cost reductions to achieve wide deployment and is found to be more valuable in some locations with greater renewable deployment. Differences between more solar- and wind-reliant regions are also found: Storage technologies with lower energy capacities are deployed to support solar deployment, and higher energy capacity technologies support wind. Finally, we identify potential future research and areas of improvement to build on this initial analysis.« less

Automated Test for NASA CFS

NASA Technical Reports Server (NTRS)

McComas, David C.; Strege, Susanne L.; Carpenter, Paul B. Hartman, Randy

2015-01-01

The core Flight System (cFS) is a flight software (FSW) product line developed by the Flight Software Systems Branch (FSSB) at NASA's Goddard Space Flight Center (GSFC). The cFS uses compile-time configuration parameters to implement variable requirements to enable portability across embedded computing platforms and to implement different end-user functional needs. The verification and validation of these requirements is proving to be a significant challenge. This paper describes the challenges facing the cFS and the results of a pilot effort to apply EXB Solution's testing approach to the cFS applications.

Potential of laser for SPS power transmission

NASA Technical Reports Server (NTRS)

Bain, C. N.

1978-01-01

Research on the feasibility of using a laser subsystem as an additional option for the transmission of the satellite power system (STS) power is presented. Current laser work and predictions for future laser performance provide a level of confidence that the development of a laser power transmission system is technologically feasible in the time frame required to develop the SBS. There are significant economic advantages in lower ground distribution costs and a reduction of more than two orders of magnitude in real estate requirements for ground based receiving/conversion sites.

Elevated-Temperature Tensile-Testing of Foil-Gage Metals

NASA Technical Reports Server (NTRS)

Blackburn, L. B.; Ellingsworth, J. R.

1986-01-01

Automated system for measuring strain in metal foils at temperatures above 500 degrees F (260 degrees C) uses mechanical extensometer and displacement transducer. System includes counterbalance feature, which eliminates weight contribution of extensometer and reduces grip pressure required for attachment to specimen. Counterbalancing feature overcomes two major difficulties in using extensometers with foil-gage specimens: (1) Weight of extensometer and transducer represents significant fraction of total load applied to specimen and may actually damage it; and (2) grip pressure required for attachment of extensometer to specimens may induce bending stresses in foil-gage materials.

Systems Toxicology: Real World Applications and Opportunities.

PubMed

Hartung, Thomas; FitzGerald, Rex E; Jennings, Paul; Mirams, Gary R; Peitsch, Manuel C; Rostami-Hodjegan, Amin; Shah, Imran; Wilks, Martin F; Sturla, Shana J

2017-04-17

Systems Toxicology aims to change the basis of how adverse biological effects of xenobiotics are characterized from empirical end points to describing modes of action as adverse outcome pathways and perturbed networks. Toward this aim, Systems Toxicology entails the integration of in vitro and in vivo toxicity data with computational modeling. This evolving approach depends critically on data reliability and relevance, which in turn depends on the quality of experimental models and bioanalysis techniques used to generate toxicological data. Systems Toxicology involves the use of large-scale data streams ("big data"), such as those derived from omics measurements that require computational means for obtaining informative results. Thus, integrative analysis of multiple molecular measurements, particularly acquired by omics strategies, is a key approach in Systems Toxicology. In recent years, there have been significant advances centered on in vitro test systems and bioanalytical strategies, yet a frontier challenge concerns linking observed network perturbations to phenotypes, which will require understanding pathways and networks that give rise to adverse responses. This summary perspective from a 2016 Systems Toxicology meeting, an international conference held in the Alps of Switzerland, describes the limitations and opportunities of selected emerging applications in this rapidly advancing field. Systems Toxicology aims to change the basis of how adverse biological effects of xenobiotics are characterized, from empirical end points to pathways of toxicity. This requires the integration of in vitro and in vivo data with computational modeling. Test systems and bioanalytical technologies have made significant advances, but ensuring data reliability and relevance is an ongoing concern. The major challenge facing the new pathway approach is determining how to link observed network perturbations to phenotypic toxicity.

Systems Toxicology: Real World Applications and Opportunities

PubMed Central

2017-01-01

Systems Toxicology aims to change the basis of how adverse biological effects of xenobiotics are characterized from empirical end points to describing modes of action as adverse outcome pathways and perturbed networks. Toward this aim, Systems Toxicology entails the integration of in vitro and in vivo toxicity data with computational modeling. This evolving approach depends critically on data reliability and relevance, which in turn depends on the quality of experimental models and bioanalysis techniques used to generate toxicological data. Systems Toxicology involves the use of large-scale data streams (“big data”), such as those derived from omics measurements that require computational means for obtaining informative results. Thus, integrative analysis of multiple molecular measurements, particularly acquired by omics strategies, is a key approach in Systems Toxicology. In recent years, there have been significant advances centered on in vitro test systems and bioanalytical strategies, yet a frontier challenge concerns linking observed network perturbations to phenotypes, which will require understanding pathways and networks that give rise to adverse responses. This summary perspective from a 2016 Systems Toxicology meeting, an international conference held in the Alps of Switzerland, describes the limitations and opportunities of selected emerging applications in this rapidly advancing field. Systems Toxicology aims to change the basis of how adverse biological effects of xenobiotics are characterized, from empirical end points to pathways of toxicity. This requires the integration of in vitro and in vivo data with computational modeling. Test systems and bioanalytical technologies have made significant advances, but ensuring data reliability and relevance is an ongoing concern. The major challenge facing the new pathway approach is determining how to link observed network perturbations to phenotypic toxicity. PMID:28362102

Apically Extruded Debris in Curved Root Canals Using the WaveOne Gold Reciprocating and Twisted File Adaptive Systems.

PubMed

Boijink, Daiana; Costa, Débora Delai; Hoppe, Carolina Bender; Kopper, Patrícia Maria Polli; Grecca, Fabiana Saores

2018-06-13

The purpose of this study was to evaluate apical debris extrusion associated with different kinematics in curved root canals. Forty-five extracted mandibular molars with root curvature angles ranging between 20° and 40° and curvature radii <10 mm were randomly assigned to 3 groups (n = 15) according to the kinematics used for root canal preparation: reciprocating motion with the WaveOne Gold system (Dentsply Tulsa Dental, Tulsa, OK), rotary/reciprocating motion with the Twisted File Adaptive system (SybronEndo, Orange, CA), and the manual technique. The debris apically extruded during preparation was collected into preweighed Eppendorf tubes. The tubes were then stored in an incubator at 70°C for 5 days. The extruded debris was quantified by subtracting the preinstrumentation from the postinstrumentation weight of the Eppendorf tubes. The time required for each instrumentation procedure was recorded. Data were analyzed using 1-way analysis of variance Tukey post hoc tests (∝ = 0.05). The WaveOne Gold reciprocating single-file system was associated with less extrusion of debris compared with hand files (P < .05) and the Twisted File Adaptive system (P > .05). The preparation time required by hand files was significantly longer than that required by the other techniques (P < .05). Under the conditions of this study, all of the instrumentation systems caused apical debris extrusion to some degree. The WaveOne Gold reciprocating system was associated with less debris extrusion in curved root canals compared with the manual technique and the Twisted File Adaptive system although the difference between the WaveOne Gold and Twisted File Adaptive systems was not significant. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Applications of nuclear reactor power systems to electric propulsion missions.

NASA Technical Reports Server (NTRS)

Schaupp, R. W.; Sawyer, C. D.

1971-01-01

The performance of nuclear electric propulsion systems (NEP) has been evaluated for a wide variety of missions in an attempt to establish the commonality of NEP system requirements. Emphasis was given to those requirements and system characteristics that serve as guidelines for current technology development programs. Various interactions and tradeoffs between NEP system and mission parameters are described. The results show that the most significant factors in selecting NEP system size are launch mode (direct or spiral escape) and, to a weaker extent, launch vehicle capability. Other factors such as mission, payload, and thrust time constraints, have little influence, thus allowing one NEP system to be used for many missions. The results indicated that a 100 kWe NEP would be suitable for most direct escape missions and a 250 kWe NEP system would be suitable for more demanding missions that use the spiral escape mode.

A method to measure internal contact angle in opaque systems by magnetic resonance imaging.

PubMed

Zhu, Weiqin; Tian, Ye; Gao, Xuefeng; Jiang, Lei

2013-07-23

Internal contact angle is an important parameter for internal wettability characterization. However, due to the limitation of optical imaging, methods available for contact angle measurement are only suitable for transparent or open systems. For most of the practical situations that require contact angle measurement in opaque or enclosed systems, the traditional methods are not effective. Based upon the requirement, a method suitable for contact angle measurement in nontransparent systems is developed by employing MRI technology. In the Article, the method is demonstrated by measuring internal contact angles in opaque cylindrical tubes. It proves that the method also shows great feasibility in transparent situations and opaque capillary systems. By using the method, contact angle in opaque systems could be measured successfully, which is significant in understanding the wetting behaviors in nontransparent systems and calculating interfacial parameters in enclosed systems.

Electric Propulsion Options for a Magnetospheric Mapping Mission

NASA Technical Reports Server (NTRS)

Oleson, Steven; Russell, Chris; Hack, Kurt; Riehl, John

1998-01-01

The Twin Electric Magnetospheric Probes Exploring on Spiral Trajectories mission concept was proposed as a Middle Explorer class mission. A pre-phase-A design was developed which utilizes the advantages of electric propulsion for Earth scientific spacecraft use. This paper presents propulsion system analyses performed for the proposal. The proposed mission required two spacecraft to explore near circular orbits 0.1 to 15 Earth radii in both high and low inclination orbits. Since the use of chemical propulsion would require launch vehicles outside the Middle Explorer class a reduction in launch mass was sought using ion, Hall, and arcjet electric propulsion system. Xenon ion technology proved to be the best propulsion option for the mission requirements requiring only two Pegasus XL launchers. The Hall thruster provided an alternative solution but required two larger, Taurus launch vehicles. Arcjet thrusters did not allow for significant launch vehicle reduction in the Middle Explorer class.

Scope for improved eco-efficiency varies among diverse cropping systems.

PubMed

Carberry, Peter S; Liang, Wei-li; Twomlow, Stephen; Holzworth, Dean P; Dimes, John P; McClelland, Tim; Huth, Neil I; Chen, Fu; Hochman, Zvi; Keating, Brian A

2013-05-21

Global food security requires eco-efficient agriculture to produce the required food and fiber products concomitant with ecologically efficient use of resources. This eco-efficiency concept is used to diagnose the state of agricultural production in China (irrigated wheat-maize double-cropping systems), Zimbabwe (rainfed maize systems), and Australia (rainfed wheat systems). More than 3,000 surveyed crop yields in these three countries were compared against simulated grain yields at farmer-specified levels of nitrogen (N) input. Many Australian commercial wheat farmers are both close to existing production frontiers and gain little prospective return from increasing their N input. Significant losses of N from their systems, either as nitrous oxide emissions or as nitrate leached from the soil profile, are infrequent and at low intensities relative to their level of grain production. These Australian farmers operate close to eco-efficient frontiers in regard to N, and so innovations in technologies and practices are essential to increasing their production without added economic or environmental risks. In contrast, many Chinese farmers can reduce N input without sacrificing production through more efficient use of their fertilizer input. In fact, there are real prospects for the double-cropping systems on the North China Plain to achieve both production increases and reduced environmental risks. Zimbabwean farmers have the opportunity for significant production increases by both improving their technical efficiency and increasing their level of input; however, doing so will require improved management expertise and greater access to institutional support for addressing the higher risks. This paper shows that pathways for achieving improved eco-efficiency will differ among diverse cropping systems.

Enabling MPEG-2 video playback in embedded systems through improved data cache efficiency

NASA Astrophysics Data System (ADS)

Soderquist, Peter; Leeser, Miriam E.

1999-01-01

Digital video decoding, enabled by the MPEG-2 Video standard, is an important future application for embedded systems, particularly PDAs and other information appliances. Many such system require portability and wireless communication capabilities, and thus face severe limitations in size and power consumption. This places a premium on integration and efficiency, and favors software solutions for video functionality over specialized hardware. The processors in most embedded system currently lack the computational power needed to perform video decoding, but a related and equally important problem is the required data bandwidth, and the need to cost-effectively insure adequate data supply. MPEG data sets are very large, and generate significant amounts of excess memory traffic for standard data caches, up to 100 times the amount required for decoding. Meanwhile, cost and power limitations restrict cache sizes in embedded systems. Some systems, including many media processors, eliminate caches in favor of memories under direct, painstaking software control in the manner of digital signal processors. Yet MPEG data has locality which caches can exploit if properly optimized, providing fast, flexible, and automatic data supply. We propose a set of enhancements which target the specific needs of the heterogeneous types within the MPEG decoder working set. These optimizations significantly improve the efficiency of small caches, reducing cache-memory traffic by almost 70 percent, and can make an enhanced 4 KB cache perform better than a standard 1 MB cache. This performance improvement can enable high-resolution, full frame rate video playback in cheaper, smaller system than woudl otherwise be possible.

Scope for improved eco-efficiency varies among diverse cropping systems

PubMed Central

Carberry, Peter S.; Liang, Wei-li; Twomlow, Stephen; Holzworth, Dean P.; Dimes, John P.; McClelland, Tim; Huth, Neil I.; Chen, Fu; Hochman, Zvi; Keating, Brian A.

2013-01-01

Global food security requires eco-efficient agriculture to produce the required food and fiber products concomitant with ecologically efficient use of resources. This eco-efficiency concept is used to diagnose the state of agricultural production in China (irrigated wheat–maize double-cropping systems), Zimbabwe (rainfed maize systems), and Australia (rainfed wheat systems). More than 3,000 surveyed crop yields in these three countries were compared against simulated grain yields at farmer-specified levels of nitrogen (N) input. Many Australian commercial wheat farmers are both close to existing production frontiers and gain little prospective return from increasing their N input. Significant losses of N from their systems, either as nitrous oxide emissions or as nitrate leached from the soil profile, are infrequent and at low intensities relative to their level of grain production. These Australian farmers operate close to eco-efficient frontiers in regard to N, and so innovations in technologies and practices are essential to increasing their production without added economic or environmental risks. In contrast, many Chinese farmers can reduce N input without sacrificing production through more efficient use of their fertilizer input. In fact, there are real prospects for the double-cropping systems on the North China Plain to achieve both production increases and reduced environmental risks. Zimbabwean farmers have the opportunity for significant production increases by both improving their technical efficiency and increasing their level of input; however, doing so will require improved management expertise and greater access to institutional support for addressing the higher risks. This paper shows that pathways for achieving improved eco-efficiency will differ among diverse cropping systems. PMID:23671071

Lightweight Damage Tolerant, High-Temperature Radiators for Nuclear Power and Propulsion

NASA Technical Reports Server (NTRS)

Craven, Paul D.; SanSoucie, Michael P.

2015-01-01

NASA is increasingly emphasizing exploration to bodies beyond near-Earth orbit. New propulsion systems and new spacecraft are being built for these missions. As the target bodies get further out from Earth, high energy density systems, e.g., nuclear fusion, for propulsion and power will be advantageous. The mass and size of these systems, including supporting systems such as the heat exchange system, including thermal radiators, will need to be as small as possible. Conventional heat exchange systems are a significant portion of the total thermal management mass and size. Nuclear electric propulsion (NEP) is a promising option for high-speed, in-space travel due to the high energy density of nuclear fission power sources and efficient electric thrusters. Heat from the reactor is converted to power for use in propulsion or for system power. The heat not used in the power conversion is then radiated to space as shown in figure 1. Advanced power conversion technologies will require high operating temperatures and would benefit from lightweight radiator materials. Radiator performance dictates power output for nuclear electric propulsion systems. Pitch-based carbon fiber materials have the potential to offer significant improvements in operating temperature, thermal conductivity, and mass. These properties combine to allow significant decreases in the total mass of the radiators and significant increases in the operating temperature of the fins. A Center-funded project at NASA Marshall Space Flight Center has shown that high thermal conductivity, woven carbon fiber fins with no matrix material, can be used to dissipate waste heat from NEP systems and because of high specific power (kW/kg), will require less mass and possibly less total area than standard metal and composite radiator fins for radiating the same amount of heat. This project uses an innovative approach to reduce the mass and size required for the thermal radiators to the point that in-space NEP and power is enabled. High thermal conductivity carbon fibers are lightweight, damage tolerant, and can be heated to high temperature. Areal densities in the NASA set target range of 2 to 4 kg/m2 (for enabling NEP) are achieved and with specific powers (kW/kg) a factor of about 7 greater than conventional metal fins and about 1.5 greater than carbon composite fins. Figure 2 shows one fin under test. All tests were done under vacuum conditions.

Development and Performance Evaluations of HfO2-Si and Rare Earth-Si Based Environmental Barrier Bond Coat Systems for SiC/SiC Ceramic Matrix Composites

NASA Technical Reports Server (NTRS)

Zhu, Dongming

2014-01-01

Ceramic environmental barrier coatings (EBC) and SiCSiC ceramic matrix composites (CMCs) will play a crucial role in future aircraft propulsion systems because of their ability to significantly increase engine operating temperatures, improve component durability, reduce engine weight and cooling requirements. Advanced EBC systems for SiCSiC CMC turbine and combustor hot section components are currently being developed to meet future turbine engine emission and performance goals. One of the significant material development challenges for the high temperature CMC components is to develop prime-reliant, high strength and high temperature capable environmental barrier coating bond coat systems, since the current silicon bond coat cannot meet the advanced EBC-CMC temperature and stability requirements. In this paper, advanced NASA HfO2-Si based EBC bond coat systems for SiCSiC CMC combustor and turbine airfoil applications are investigated. The coating design approach and stability requirements are specifically emphasized, with the development and implementation focusing on Plasma Sprayed (PS) and Electron Beam-Physic Vapor Deposited (EB-PVD) coating systems and the composition optimizations. High temperature properties of the HfO2-Si based bond coat systems, including the strength, fracture toughness, creep resistance, and oxidation resistance were evaluated in the temperature range of 1200 to 1500 C. Thermal gradient heat flux low cycle fatigue and furnace cyclic oxidation durability tests were also performed at temperatures up to 1500 C. The coating strength improvements, degradation and failure modes of the environmental barrier coating bond coat systems on SiCSiC CMCs tested in simulated stress-environment interactions are briefly discussed and supported by modeling. The performance enhancements of the HfO2-Si bond coat systems with rare earth element dopants and rare earth-silicon based bond coats are also highlighted. The advanced bond coat systems, when integrated with advanced EBC top coats, showed promise to achieve 1500 C temperature capability, helping enable next generation turbine engines with significantly improved engine component temperature capability and long-term durability.

Evaluation of ARCAM Deposited Ti-6Al-4V

NASA Technical Reports Server (NTRS)

Slattery, Kevin; Slaughter, Blake; Speorl, Emily; Good, James; Gilley, Scott; McLemore, Carole

2008-01-01

A wide range of Metal Additive Manufacturing (MAM) technologies are becoming available. One of the challenges in using new technologies for aerospace systems is demonstrating that the process and system has the ability to manufacture components that meet the high quality requirements on a statistically significant basis. The widest-used system for small to medium sized components is the ARCAM system manufactured in Gothenburg, Sweden. This system features a 4kW electron-beam gun, and has a chamber volume of 250mm long x 250mm wide x 250mm to 400mm tall. This paper will describe the basis for the quality and consistency requirements, the experimental and evaluation procedures used for the evaluation, and an analysis of the results for Ti-6Al-4V.

A new verification film system for routine quality control of radiation fields: Kodak EC-L.

PubMed

Hermann, A; Bratengeier, K; Priske, A; Flentje, M

2000-06-01

The use of modern irradiation techniques requires better verification films for determining set-up deviations and patient movements during the course of radiation treatment. This is an investigation of the image quality and time requirement of a new verification film system compared to a conventional portal film system. For conventional verifications we used Agfa Curix HT 1000 films which were compared to the new Kodak EC-L film system. 344 Agfa Curix HT 1000 and 381 Kodak EC-L portal films of different tumor sites (prostate, rectum, head and neck) were visually judged on a light box by 2 experienced physicians. Subjective judgement of image quality, masking of films and time requirement were checked. In this investigation 68% of 175 Kodak EC-L ap/pa-films were judged "good", only 18% were classified "moderate" or "poor" 14%, but only 22% of 173 conventional ap/pa verification films (Agfa Curix HT 1000) were judged to be "good". The image quality, detail perception and time required for film inspection of the new Kodak EC-L film system was significantly improved when compared with standard portal films. They could be read more accurately and the detection of set-up deviation was facilitated.

US computer research networks: Current and future

NASA Technical Reports Server (NTRS)

Kratochvil, D.; Sood, D.; Verostko, A.

1989-01-01

During the last decade, NASA LeRC's Communication Program has conducted a series of telecommunications forecasting studies to project trends and requirements and to identify critical telecommunications technologies that must be developed to meet future requirements. The Government Networks Division of Contel Federal Systems has assisted NASA in these studies, and the current study builds upon these earlier efforts. The current major thrust of the NASA Communications Program is aimed at developing the high risk, advanced, communications satellite and terminal technologies required to significantly increase the capacity of future communications systems. Also, major new technological, economic, and social-political events and trends are now shaping the communications industry of the future. Therefore, a re-examination of future telecommunications needs and requirements is necessary to enable NASA to make management decisions in its Communications Program and to ensure the proper technologies and systems are addressed. This study, through a series of Task Orders, is helping NASA define the likely communication service needs and requirements of the future and thereby ensuring that the most appropriate technology developments are pursued.

Unmanned Aircraft System Control and ATC Communications Bandwidth Requirements

NASA Technical Reports Server (NTRS)

Henriksen, Steve

2008-01-01

There are significant activities taking place to establish the procedures and requirements for safe and routine operation of unmanned aircraft systems (UAS) in the National Airspace System (NAS). Among the barriers to overcome in achieving this goal is the lack of sufficient frequency spectrum necessary for the UAS control and air traffic control (ATC) communications links. This shortcoming is compounded by the fact that the UAS control communications links will likely be required to operate in protected frequency spectrum, just as ATC communications links are, because they relate to "safety and regularity of flight." To support future International Telecommunications Union (ITU) World Radio Conference (WRC) agenda items concerning new frequency allocations for UAS communications links, and to augment the Future Communications Study (FCS) Technology Evaluation Group efforts, NASA Glenn Research Center has sponsored a task to estimate the UAS control and ATC communications bandwidth requirements for safe, reliable, and routine operation of UAS in the NAS. This report describes the process and results of that task. The study focused on long-term bandwidth requirements for UAS approximately through 2030.

The significance of requirements engineering for the medical domain.

PubMed

Kossmann, Mario

2014-07-01

This paper aims to raise awareness of the importance of Requirements Engineering (RE) for the successful and efficient development of high-quality systems and products for the medical domain. It does so by providing an introduction to RE from the viewpoints of project and programme management and systems engineering in general and by illustrating the usefulness of a sound RE approach to the development of a local healthcare system in a deprived region in central Africa. The paper concludes that RE is just as crucial for the development of systems and products in the medical domain, as it is for the development of systems in the aerospace industry or software systems in the consumer electronics industry; while the degree of detail and formality of how RE is used has to be tailored to fit the context in question.

Automatic systems and the low-level wind hazard

NASA Technical Reports Server (NTRS)

Schaeffer, Dwight R.

1987-01-01

Automatic flight control systems provide means for significantly enhancing survivability in severe wind hazards. The technology required to produce the necessary control algorithms is available and has been made technically feasible by the advent of digital flight control systems and accurate, low-noise sensors, especially strap-down inertial sensors. The application of this technology and these means has not generally been enabled except for automatic landing systems, and even then the potential has not been fully exploited. To fully exploit the potential of automatic systems for enhancing safety in wind hazards requires providing incentives, creating demand, inspiring competition, education, and eliminating prejudicial disincentitives to overcome the economic penalties associated with the extensive and riskly development and certification of these systems. If these changes will come about at all, it will likely be through changes in the regulations provided by the certifying agencies.

System and Method for Multi-Wavelength Optical Signal Detection

NASA Technical Reports Server (NTRS)

McGlone, Thomas D. (Inventor)

2017-01-01

The system and method for multi-wavelength optical signal detection enables the detection of optical signal levels significantly below those processed at the discrete circuit level by the use of mixed-signal processing methods implemented with integrated circuit technologies. The present invention is configured to detect and process small signals, which enables the reduction of the optical power required to stimulate detection networks, and lowers the required laser power to make specific measurements. The present invention provides an adaptation of active pixel networks combined with mixed-signal processing methods to provide an integer representation of the received signal as an output. The present invention also provides multi-wavelength laser detection circuits for use in various systems, such as a differential absorption light detection and ranging system.

A cryogen-free ultralow-field superconducting quantum interference device magnetic resonance imaging system.

PubMed

Eom, Byeong Ho; Penanen, Konstantin; Hahn, Inseob

2014-09-01

Magnetic resonance imaging (MRI) at microtesla fields using superconducting quantum interference device (SQUID) detection has previously been demonstrated, and advantages have been noted. Although the ultralow-field SQUID MRI technique would not need the heavy superconducting magnet of conventional MRI systems, liquid helium required to cool the low-temperature detector still places a significant burden on its operation. We have built a prototype cryocooler-based SQUID MRI system that does not require a cryogen. The SQUID detector and the superconducting gradiometer were cooled down to 3.7 K and 4.3 K, respectively. We describe the prototype design, characterization, a phantom image, and areas of further improvements needed to bring the imaging performance to parity with conventional MRI systems.

Monitoring and control technologies for bioregenerative life support systems/CELSS

NASA Technical Reports Server (NTRS)

Knott, William M.; Sager, John C.

1991-01-01

The development of a controlled Ecological Life Support System (CELSS) will require NASA to develop innovative monitoring and control technologies to operate the different components of the system. Primary effort over the past three to four years has been directed toward the development of technologies to operate a biomass production module. Computer hardware and software required to operate, collect, and summarize environmental data for a large plant growth chamber facility were developed and refined. Sensors and controls required to collect information on such physical parameters as relative humidity, temperature, irradiance, pressure, and gases in the atmosphere; and PH, dissolved oxygen, fluid flow rates, and electrical conductivity in the nutrient solutions are being developed and tested. Technologies required to produce high artificial irradiance for plant growth and those required to collect and transport natural light into a plant growth chamber are also being evaluated. Significant effort was directed towards the development and testing of a membrane nutrient delivery system required to manipulate, seed, and harvest crops, and to determine plant health prior to stress impacting plant productivity are also being researched. Tissue culture technologies are being developed for use in management and propagation of crop plants. Though previous efforts have focussed on development of technologies required to operate a biomass production module for a CELSS, current efforts are expanding to include technologies required to operate modules such as food preparation, biomass processing, and resource (waste) recovery which are integral parts of the CELSS.

Implementation of a configurable laboratory information management system for use in cellular process development and manufacturing.

PubMed

Russom, Diana; Ahmed, Amira; Gonzalez, Nancy; Alvarnas, Joseph; DiGiusto, David

2012-01-01

Regulatory requirements for the manufacturing of cell products for clinical investigation require a significant level of record-keeping, starting early in process development and continuing through to the execution and requisite follow-up of patients on clinical trials. Central to record-keeping is the management of documentation related to patients, raw materials, processes, assays and facilities. To support these requirements, we evaluated several laboratory information management systems (LIMS), including their cost, flexibility, regulatory compliance, ongoing programming requirements and ability to integrate with laboratory equipment. After selecting a system, we performed a pilot study to develop a user-configurable LIMS for our laboratory in support of our pre-clinical and clinical cell-production activities. We report here on the design and utilization of this system to manage accrual with a healthy blood-donor protocol, as well as manufacturing operations for the production of a master cell bank and several patient-specific stem cell products. The system was used successfully to manage blood donor eligibility, recruiting, appointments, billing and serology, and to provide annual accrual reports. Quality management reporting features of the system were used to capture, report and investigate process and equipment deviations that occurred during the production of a master cell bank and patient products. Overall the system has served to support the compliance requirements of process development and phase I/II clinical trial activities for our laboratory and can be easily modified to meet the needs of similar laboratories.

Fort Hood Solar Total Energy Project. Volume II. Preliminary design. Part 1. System criteria and design description. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

None,

1979-01-01

This volume documents the preliminary design developed for the Solar Total Energy System to be installed at Fort Hood, Texas. Current system, subsystem, and component designs are described and additional studies which support selection among significant design alternatives are presented. Overall system requirements which form the system design basis are presented. These include program objectives; performance and output load requirements; industrial, statutory, and regulatory standards; and site interface requirements. Material in this section will continue to be issued separately in the Systems Requirements Document and maintained current through revision throughout future phases of the project. Overall system design and detailedmore » subsystem design descriptions are provided. Consideration of operation and maintenance is reflected in discussion of each subsystem design as well as in an integrated overall discussion. Included are the solar collector subsystem; the thermal storage subsystem, the power conversion sybsystem (including electrical generation and distribution); the heating/cooling and domestic hot water subsystems; overall instrumentation and control; and the STES building and physical plant. The design of several subsystems has progressed beyond the preliminary stage; descriptions for such subsystems are therefore provided in more detail than others to provide complete documentation of the work performed. In some cases, preliminary design parameters require specific verificaton in the definitive design phase and are identified in the text. Subsystem descriptions will continue to be issued and revised separately to maintain accuracy during future phases of the project. (WHK)« less

Application of Semi Active Control Techniques to the Damping Suppression Problem of Solar Sail Booms

NASA Technical Reports Server (NTRS)

Adetona, O.; Keel, L. H.; Whorton, M. S.

2007-01-01

Solar sails provide a propellant free form for space propulsion. These are large flat surfaces that generate thrust when they are impacted by light. When attached to a space vehicle, the thrust generated can propel the space vehicle to great distances at significant speeds. For optimal performance the sail must be kept from excessive vibration. Active control techniques can provide the best performance. However, they require an external power-source that may create significant parasitic mass to the solar sail. However, solar sails require low mass for optimal performance. Secondly, active control techniques typically require a good system model to ensure stability and performance. However, the accuracy of solar sail models validated on earth for a space environment is questionable. An alternative approach is passive vibration techniques. These do not require an external power supply, and do not destabilize the system. A third alternative is referred to as semi-active control. This approach tries to get the best of both active and passive control, while avoiding their pitfalls. In semi-active control, an active control law is designed for the system, and passive control techniques are used to implement it. As a result, no external power supply is needed so the system is not destabilize-able. Though it typically underperforms active control techniques, it has been shown to out-perform passive control approaches and can be unobtrusively installed on a solar sail boom. Motivated by this, the objective of this research is to study the suitability of a Piezoelectric (PZT) patch actuator/sensor based semi-active control system for the vibration suppression problem of solar sail booms. Accordingly, we develop a suitable mathematical and computer model for such studies and demonstrate the capabilities of the proposed approach with computer simulations.

A cloud-based home health care information sharing system to connect patients with home healthcare staff -A case report of a study in a mountainous region.

PubMed

Nomoto, Shinichi; Utsumi, Momoe; Sasayama, Satoshi; Dekigai, Hiroshi

2017-01-01

We have developed a cloud system, the e-Renraku Notebook (e-RN) for sharing of home care information based on the concept of "patient-centricity". In order to assess the likelihood that our system will enhance the communication and sharing of information between home healthcare staff members and home-care patients, we selected patients who were residing in mountainous regions for inclusion in our study. We herein report the findings.Eighteen staff members from 7 medical facilities and 9 patients participated in the present study.The e-RN was developed for two reasons: to allow patients to independently report their health status and to have staff members view and respond to the information received. The patients and staff members were given iPads with the pre-installed applications and the information being exchanged was reviewed over a 54-day period.Information was mainly input by the patients (61.6%), followed by the nurses who performed home visits (19.9%). The amount of information input by patients requiring high-level nursing care and their corresponding staff member was significantly greater than that input by patients who required low-level of nursing care.This patient-centric system in which patients can independently report and share information with a member of the healthcare staff provides a sense of security. It also allows staff members to understand the patient's health status before making a home visit, thereby giving them a sense of security and confidence. It was also noteworthy that elderly patients requiring high-level nursing care and their staff counterpart input information in the system significantly more frequently than patients who required low-level care.

Annual Change Report 2006/2007

DOE Office of Scientific and Technical Information (OSTI.GOV)

Washington Regulatory and Environmental Services; Washington TRU Solutions LLC

2007-11-16

As part of continuing compliance, the U.S. Environmental Protection Agency (EPA) requires the U.S. Department of Energy (DOE) to provide information on any change in conditions or activities pertaining to the disposal system since the most recent compliance application. This requirement is identified in Title 40 Code of Federal Regulations (CFR), Section 194.4(b)(4), which states: "No later than six months after the administrator issues a certification, and at least annually thereafter, the Department shall report to the Administrator, in writing, any changes in conditions or activities pertaining to the disposal system that were not required to be reported by paragraphmore » (b)(3) of this section and that differ from information contained in the most recent compliance application." In meeting the requirement, the DOE provides an annual report each November of all applicable changes under the above requirement. This annual report informs the EPA of changes to information in the most recent compliance recertification (the 2004 Compliance Recertification). Significant planned changes must be reported to the EPA prior to implementation by the DOE. In addition, Title 40 CFR, Section 194.4(b)(3) requires that significant unplanned changes be reported to the EPA within 24 hours or ten days, depending on the severity of the activity or condition. To date, there have been no significant unplanned changes to the certification basis. Planned changes have been submitted on an individual basis. All other changes are reported annually. Changes in activities or conditions are reviewed to determine if 40 CFR Section 194.4(b)(3) reporting is necessary. As indicated above, no significant unplanned changes were identified for the time period covered by this report. The enclosed tables list those items identified for reporting under 40 CFR Section 194.4(b)(4). The majority of the items described in this report are inspections, reports, and modifications to written plans and procedures for WIPP operations.« less

Shuttle avionics software trials, tribulations and success

NASA Technical Reports Server (NTRS)

Henderson, O. L.

1985-01-01

The early problems and the solutions developed to provide the required quality software needed to support the space shuttle engine development program are described. The decision to use a programmable digital control system on the space shuttle engine was primarily based upon the need for a flexible control system capable of supporting the total engine mission on a large complex pump fed engine. The mission definition included all control phases from ground checkout through post shutdown propellant dumping. The flexibility of the controller through reprogrammable software allowed the system to respond to the technical challenges and innovation required to develop both the engine and controller hardware. This same flexibility, however, placed a severe strain on the capability of the software development and verification organization. The overall development program required that the software facility accommodate significant growth in both the software requirements and the number of software packages delivered. This challenge was met by reorganization and evolution in the process of developing and verifying software.

Effects of state organizational structure and forensic examiner training on pretrial competence assessments.

PubMed

Edens, J F; Poythress, N G; Nicholson, R A; Otto, R K

1999-05-01

States differ widely in their delivery of pretrial forensic evaluation services, in terms of organizational structure and training requirements of forensic examiners. It was hypothesized that defendants adjudicated incompetent to proceed in states using community-based, private-practitioner systems would show less impairment on a competence assessment measure, the MacArthur Competence Assessment Tool-Criminal Adjudication (MacCAT-CA), than defendants adjudicated incompetent in states using traditional, inpatient systems. It also was hypothesized that mean MacCAT-CA scores for incompetent defendants from states requiring forensic training/certification would be lower than for defendants from states lacking such requirements. Results indicated significant differences across the four types of service delivery systems examined. However, planned comparisons revealed no differences between a state using a traditional, inpatient model and a state employing a community-based, private-practitioner model. Analyses examining the effects of mandatory forensic training failed to support the hypothesis that training requirements result in the adoption of higher thresholds for determining incompetence.

Validity evidence for the Simulated Colonoscopy Objective Performance Evaluation scoring system.

PubMed

Trinca, Kristen D; Cox, Tiffany C; Pearl, Jonathan P; Ritter, E Matthew

2014-02-01

Low-cost, objective systems to assess and train endoscopy skills are needed. The aim of this study was to evaluate the ability of Simulated Colonoscopy Objective Performance Evaluation to assess the skills required to perform endoscopy. Thirty-eight subjects were included in this study, all of whom performed 4 tasks. The scoring system measured performance by calculating precision and efficiency. Data analysis assessed the relationship between colonoscopy experience and performance on each task and the overall score. Endoscopic trainees' Simulated Colonoscopy Objective Performance Evaluation scores correlated significantly with total colonoscopy experience (r = .61, P = .003) and experience in the past 12 months (r = .63, P = .002). Significant differences were seen among practicing endoscopists, nonendoscopic surgeons, and trainees (P < .0001). When the 4 tasks were analyzed, each showed significant correlation with colonoscopy experience (scope manipulation, r = .44, P = .044; tool targeting, r = .45, P = .04; loop management, r = .47, P = .032; mucosal inspection, r = .65, P = .001) and significant differences in performance between the endoscopist groups, except for mucosal inspection (scope manipulation, P < .0001; tool targeting, P = .002; loop management, P = .0008; mucosal inspection, P = .27). Simulated Colonoscopy Objective Performance Evaluation objectively assesses the technical skills required to perform endoscopy and shows promise as a platform for proficiency-based skills training. Published by Elsevier Inc.

A coupling method for a cardiovascular simulation model which includes the Kalman filter.

PubMed

Hasegawa, Yuki; Shimayoshi, Takao; Amano, Akira; Matsuda, Tetsuya

2012-01-01

Multi-scale models of the cardiovascular system provide new insight that was unavailable with in vivo and in vitro experiments. For the cardiovascular system, multi-scale simulations provide a valuable perspective in analyzing the interaction of three phenomenons occurring at different spatial scales: circulatory hemodynamics, ventricular structural dynamics, and myocardial excitation-contraction. In order to simulate these interactions, multiscale cardiovascular simulation systems couple models that simulate different phenomena. However, coupling methods require a significant amount of calculation, since a system of non-linear equations must be solved for each timestep. Therefore, we proposed a coupling method which decreases the amount of calculation by using the Kalman filter. In our method, the Kalman filter calculates approximations for the solution to the system of non-linear equations at each timestep. The approximations are then used as initial values for solving the system of non-linear equations. The proposed method decreases the number of iterations required by 94.0% compared to the conventional strong coupling method. When compared with a smoothing spline predictor, the proposed method required 49.4% fewer iterations.

Exploring Propulsion System Requirements for More and All-Electric Helicopters

NASA Technical Reports Server (NTRS)

Snyder, Christopher A.

2015-01-01

Helicopters offer unique capabilities that are important for certain missions. More and all-electric propulsion systems for helicopters offer the potential for improved efficiency, reliability, vehicle and mission capabilities as well as reduced harmful emissions. To achieve these propulsion system-based benefits, the relevant requirements must be understood and developed for the various component, sub-component and ancillary systems of the overall propulsion system. Three representative helicopters were used to explore propulsion and overall vehicle and mission requirements. These vehicles varied from light utility (one to three occupants) to highly capable (three crew members plus ten passengers and cargo). Assuming 15 and 30 year technology availability, analytical models for electric system components were developed to understand component and ancillary requirements. Overall propulsion system characteristics were developed and used for vehicle sizing and mission analyses to understand the tradeoffs of component performance and weight, with increase in vehicle size and mission capability. Study results indicate that only the light utility vehicle retained significant payload for an arbitrary 100 nautical mile range assuming 15 year technology. Thirty year technology assumptions for battery energy storage are sufficient to enable some range and payload capabilities, but further improvements in energy density are required to maintain or exceed payload and range capabilities versus present systems. Hydrocarbon-fueled range extenders can be prudently used to recover range and payload deficiencies resulting from battery energy density limitations. Thermal loads for electric systems are low heat quality, but seem manageable. To realize the benefits from more and all-electric systems, technology goals must be achieved, as well as vehicles, missions and systems identified that are best suited to take advantage of their unique characteristics.

Exploring Propulsion System Requirements for More and All-Electric Helicopters

NASA Technical Reports Server (NTRS)

Snyder, Christopher A.

2015-01-01

Helicopters offer unique capabilities that are important for certain missions. More and all-electric propulsion systems for helicopters offer the potential for improved efficiency, reliability, vehicle and mission capabilities as well as reduced harmful emissions. To achieve these propulsion system-based benefits, the relevant requirements must be understood and developed for the various component, sub-component and ancillary systems of the overall propulsion system. Three representative helicopters were used to explore propulsion and overall vehicle and mission requirements. These vehicles varied from light utility (one to three occupants) to highly capable (three crew members plus ten passengers and cargo). Assuming 15 and 30 year technology availability, analytical models for electric system components were developed to understand component and ancillary requirements. Overall propulsion system characteristics were developed and used for vehicle sizing and mission analyses to understand the tradeoffs of component performance and weight, with increase in vehicle size and mission capability. Study results indicate that only the light utility vehicle retained significant payload for an arbitrary 100 nautical mile range assuming 15 year technology. Thirty year technology assumptions for battery energy storage are sufficient to enable some range and payload capabilities, but further improvements in energy density are required to maintain or exceed payload and range capabilities versus present systems. Hydrocarbon-fueled range extenders can be prudently used to recover range and payload deficiencies resulting from battery energy density limitations. Thermal loads for electric systems are low heat quality, but seem manageable. To realize the benefits from more and all-electric systems, technology goals must be achieved, as well as identify vehicles, missions and systems that are best suited to take advantage of their unique characteristics.

Integrated orbital servicing study follow-on. Volume 2: Technical analysis and system design

NASA Technical Reports Server (NTRS)

1978-01-01

In-orbit service functional and physical requirements to support both low and high Earth orbit servicing/maintenance operations were defined, an optimum servicing system configuration was developed and mockups and early prototype hardware were fabricated to demonstrate and validate the concepts selected. Significant issues addressed include criteria for concept selection; representative mission equipment and approaches to their design for serviceability; significant serviceable spacecraft design aspects; servicer mechanism operation in one-g; approaches for the demonstration/simulation; and service mechanism structure design approach.

Fission Technology for Exploring and Utilizing the Solar System

NASA Technical Reports Server (NTRS)

Houts, Mike; VanDyke, Melissa; Godfroy, Tom; Pedersen, Kevin; Martin, James; Dickens, Ricky; Salvail, Pat; Hrbub, Ivana; Schmidt, George R. (Technical Monitor)

2000-01-01

Fission technology can enable rapid, affordable access to any point in the solar system. Potential fission-based transportation options include bimodal nuclear thermal rockets, high specific energy propulsion systems, and pulsed fission propulsion systems. In-space propellant re-supply enhances the effective performance of all systems, but requires significant infrastructure development. Safe, timely, affordable utilization of first-generation space fission propulsion systems will enable the development of more advanced systems. First generation space systems will build on over 45 years of US and international space fission system technology development to minimize cost,

Energy Requirements of Hydrogen-utilizing Microbes: A Boundary Condition for Subsurface Life

NASA Technical Reports Server (NTRS)

Hoehler, Tori M.; Alperin, Marc J.; Albert, Daniel B.; Martens, Christopher S.

2003-01-01

Microbial ecosystems based on the energy supplied by water-rock chemistry carry particular significance in the context of geo- and astrobiology. With no direct dependence on solar energy, lithotrophic microbes could conceivably penetrate a planetary crust to a depth limited only by temperature or pressure constraints (several kilometers or more). The deep lithospheric habitat is thereby potentially much greater in volume than its surface counterpart, and in addition offers a stable refuge against inhospitable surface conditions related to climatic or atmospheric evolution (e.g., Mars) or even high-energy impacts (e.g., early in Earth's history). The possibilities for a deep microbial biosphere are, however, greatly constrained by life s need to obtain energy at a certain minimum rate (the maintenance energy requirement) and of a certain minimum magnitude (the energy quantum requirement). The mere existence of these requirements implies that a significant fraction of the chemical free energy available in the subsurface environment cannot be exploited by life. Similar limits may also apply to the usefulness of light energy at very low intensities or long wavelengths. Quantification of these minimum energy requirements in terrestrial microbial ecosystems will help to establish a criterion of energetic habitability that can significantly constrain the prospects for life in Earth's subsurface, or on other bodies in the solar system. Our early work has focused on quantifying the biological energy quantum requirement for methanogenic archaea, as representatives of a plausible subsurface metabolism, in anoxic sediments (where energy availability is among the most limiting factors in microbial population growth). In both field and laboratory experiments utilizing these sediments, methanogens retain a remarkably consistent free energy intake, in the face of fluctuating environmental conditions that affect energy availability. The energy yields apparently required by methanogens in these sediment systems for sustained metabolism are about half that previously thought necessary. Lowered energy requirements would imply that a correspondingly greater proportion of the planetary subsurface could represent viable habitat for microorganisms.

Developing Software Requirements for a Knowledge Management System That Coordinates Training Programs with Business Processes and Policies in Large Organizations

ERIC Educational Resources Information Center

Kiper, J. Richard

2013-01-01

For large organizations, updating instructional programs presents a challenge to keep abreast of constantly changing business processes and policies. Each time a process or policy changes, significant resources are required to locate and modify the training materials that convey the new content. Moreover, without the ability to track learning…

Automation and integration of components for generalized semantic markup of electronic medical texts.

PubMed Central

Dugan, J. M.; Berrios, D. C.; Liu, X.; Kim, D. K.; Kaizer, H.; Fagan, L. M.

1999-01-01

Our group has built an information retrieval system based on a complex semantic markup of medical textbooks. We describe the construction of a set of web-based knowledge-acquisition tools that expedites the collection and maintenance of the concepts required for text markup and the search interface required for information retrieval from the marked text. In the text markup system, domain experts (DEs) identify sections of text that contain one or more elements from a finite set of concepts. End users can then query the text using a predefined set of questions, each of which identifies a subset of complementary concepts. The search process matches that subset of concepts to relevant points in the text. The current process requires that the DE invest significant time to generate the required concepts and questions. We propose a new system--called ACQUIRE (Acquisition of Concepts and Queries in an Integrated Retrieval Environment)--that assists a DE in two essential tasks in the text-markup process. First, it helps her to develop, edit, and maintain the concept model: the set of concepts with which she marks the text. Second, ACQUIRE helps her to develop a query model: the set of specific questions that end users can later use to search the marked text. The DE incorporates concepts from the concept model when she creates the questions in the query model. The major benefit of the ACQUIRE system is a reduction in the time and effort required for the text-markup process. We compared the process of concept- and query-model creation using ACQUIRE to the process used in previous work by rebuilding two existing models that we previously constructed manually. We observed a significant decrease in the time required to build and maintain the concept and query models. Images Figure 1 Figure 2 Figure 4 Figure 5 PMID:10566457

Thermal barrier coatings issues in advanced land-based gas turbines

NASA Technical Reports Server (NTRS)

Parks, W. P.; Lee, W. Y.; Wright, I. G.

1995-01-01

The Department of Energy's Advanced Turbine System (ATS) program is aimed at forecasting the development of a new generation of land-based gas turbine systems with overall efficiencies significantly beyond those of current state-of-the-art machines, as well as greatly increased times between inspection and refurbishment, improved environmental impact, and decreased cost. The proposed duty cycle of ATS turbines will require the use of different criteria in the design of the materials for the critical hot gas path components. In particular, thermal barrier coatings will be an essential feature of the hot gas path components in these machines. While such coatings are routinely used in high-performance aircraft engines and are becoming established in land-based turbines, the requirements of the ATS turbine application are sufficiently different that significant improvements in thermal barrier coating technology will be necessary. In particular, it appears that thermal barrier coatings will have to function on all airfoil sections of the first stage vanes and blades to provide the significant temperature reduction required. In contrast, such coatings applied to the blades and vances of advanced aircraft engines are intended primarily to reduce air cooling requirements and extend component lifetime; failure of those coatings can be tolerated without jeopardizing mechanical or corrosion performance. A major difference is that in ATS turbines these components will be totally reliant on thermal barrier coatings which will, therefore, need to be highly reliable even over the leading edges of first stage blades. Obviously, the ATS program provides a very challenging opportunity for TBC's, and involves some significant opportunities to extend this technology.

Plutonium Finishing Plant (PFP) HVAC System Component Index

DOE Office of Scientific and Technical Information (OSTI.GOV)

DICK, J.D.

2000-02-28

The Plutonium Finishing Plant (PFP) WAC System includes sub-systems 25A through 25K. Specific system boundaries and justifications are contained in HNF-SD-CP-SDD-005, ''Definition and Means of Maintaining the Ventilation System Confinement Portion of the PFP Safety Envelope.'' The procurement requirements associated with the system necessitates procurement of some system equipment as Commercial Grade Items in accordance with HNF-PRO-268, ''Control of Purchased Items and Services.'' This document lists safety class and safety significant components for the Heating Ventilation Air Conditioning and specifies the critical characteristics for Commercial Grade Items, as required by HNF-PRO-268 and HNF-PRO-1819. These are the minimum specifications that themore » equipment must meet in order to properly perform its safety function. There may be several manufacturers or models that meet the critical characteristics for any one item.« less

Incorporating CCSDS telemetry standards and philosophy on Cassini

NASA Technical Reports Server (NTRS)

Day, John C.; Elson, Anne B.

1995-01-01

The Cassini project at the Jet Propulsion Laboratory (JPL) is implementing a spacecraft telemetry system based on the Consultative Committee for Space Data Systems (CCSDS) packet telemetry standards. Resolving the CCSDS concepts with a Ground Data System designed to handle time-division-multiplexed telemetry and also handling constraints unique to a deep-space planetary spacecraft (such as fixed downlink opportunities, small downlink rates and requirements for on-board data storage) have resulted in spacecraft and ground system design challenges. Solving these design challenges involved adapting and extending the CCSDS telemetry standards as well as changes to the spacecraft and ground system designs. The resulting spacecraft/ground system design is an example of how new ideas and philosophies can be incorporated into existing systems and design approaches without requiring significant rework. In addition, it shows that the CCSDS telemetry standards can be successfully applied to deep-space planetary spacecraft.

Towards a Scalable Group Vehicle-based Security System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carter, Jason M

2016-01-01

In August 2014, the National Highway Traffic Safety Administration (NHTSA) proposed new rulemaking to require V2V communication in light vehicles. To establish trust in the basic safety messages (BSMs) that are exchanged by vehicles to improve driver safety, a vehicle public key infrastructure (VPKI) is required. We outline a system where a group or groups of vehicles manage and generate their own BSM signing keys and authenticating certificates -- a Vehicle-Based Security System (VBSS). Based on our preliminary examination, we assert the mechanisms exist to implement a VBSS that supports V2V communications; however, maintaining uniform trust throughout the system whilemore » protecting individual privacy does require reliance on nascent group signature technology which may require a significant amount of communication overhead for trust maintenance. To better evaluate the VBSS approach, we compare it to the proposed Security Credential Management System (SCMS) in four major areas including bootstrapping, pseudonym provisioning, BSM signing and authentication, and revocation. System scale, driver privacy, and the distribution and dynamics of participants make designing an effective VPKI an interesting and challenging problem; no clear-cut strategy exists to satisfy the security and privacy expectations in a highly efficient way. More work is needed in VPKI research, so the life-saving promise of V2V technology can be achieved.« less

Formal Requirements-Based Programming for Complex Systems

NASA Technical Reports Server (NTRS)

Rash, James L.; Hinchey, Michael G.; Rouff, Christopher A.; Gracanin, Denis

2005-01-01

Computer science as a field has not yet produced a general method to mechanically transform complex computer system requirements into a provably equivalent implementation. Such a method would be one major step towards dealing with complexity in computing, yet it remains the elusive holy grail of system development. Currently available tools and methods that start with a formal model of a system and mechanically produce a provably equivalent implementation are valuable but not sufficient. The gap that such tools and methods leave unfilled is that the formal models cannot be proven to be equivalent to the system requirements as originated by the customer For the classes of complex systems whose behavior can be described as a finite (but significant) set of scenarios, we offer a method for mechanically transforming requirements (expressed in restricted natural language, or appropriate graphical notations) into a provably equivalent formal model that can be used as the basis for code generation and other transformations. While other techniques are available, this method is unique in offering full mathematical tractability while using notations and techniques that are well known and well trusted. We illustrate the application of the method to an example procedure from the Hubble Robotic Servicing Mission currently under study and preliminary formulation at NASA Goddard Space Flight Center.

Comparing the predictive value of the pelvic ring injury classification systems by Tile and by Young and Burgess.

PubMed

Osterhoff, Georg; Scheyerer, Max J; Fritz, Yannick; Bouaicha, Samy; Wanner, Guido A; Simmen, Hans-Peter; Werner, Clément M L

2014-04-01

Radiology-based classifications of pelvic ring injuries and their relevance for the prognosis of morbidity and mortality are disputed in the literature. The purpose of this study was to evaluate potential differences between the pelvic ring injury classification systems by Tile and by Young and Burgess with regard to their predictive value on mortality, transfusion/infusion requirement and concomitant injuries. Two-hundred-and-eighty-five consecutive patients with pelvic ring fractures were analyzed for mortality within 30 days after admission, number of blood units and total volume of fluid infused during the first 24h after trauma, the Abbreviated Injury Severity (AIS) scores for head, chest, spine, abdomen and extremities as a function of the Tile and the Young-Burgess classifications. There was no significant relationship between occurrence of death and fracture pattern but a significant relationship between fracture pattern and need for blood units/total fluid volume for Tile (p<.001/p<.001) and Young-Burgess (p<.001/p<.001). In both classifications, open book fractures were associated with more fluid requirement and more severe injuries of the abdomen, spine and extremities (p<.05). When divided into the larger subgroups "partially stable" and "unstable", unstable fractures were associated with a higher mortality rate in the Young-Burgess system (p=.036). In both classifications, patients with unstable fractures required significantly more blood transfusions (p<.001) and total fluid infusion (p<.001) and higher AIS scores. In this first direct comparison of both classifications, we found no clinical relevant differences with regard to their predictive value on mortality, transfusion/infusion requirement and concomitant injuries. Copyright © 2013 Elsevier Ltd. All rights reserved.

Experimental investigation into the fault response of superconducting hybrid electric propulsion electrical power system to a DC rail to rail fault

NASA Astrophysics Data System (ADS)

Nolan, S.; Jones, C. E.; Munro, R.; Norman, P.; Galloway, S.; Venturumilli, S.; Sheng, J.; Yuan, W.

2017-12-01

Hybrid electric propulsion aircraft are proposed to improve overall aircraft efficiency, enabling future rising demands for air travel to be met. The development of appropriate electrical power systems to provide thrust for the aircraft is a significant challenge due to the much higher required power generation capacity levels and complexity of the aero-electrical power systems (AEPS). The efficiency and weight of the AEPS is critical to ensure that the benefits of hybrid propulsion are not mitigated by the electrical power train. Hence it is proposed that for larger aircraft (~200 passengers) superconducting power systems are used to meet target power densities. Central to the design of the hybrid propulsion AEPS is a robust and reliable electrical protection and fault management system. It is known from previous studies that the choice of protection system may have a significant impact on the overall efficiency of the AEPS. Hence an informed design process which considers the key trades between choice of cable and protection requirements is needed. To date the fault response of a voltage source converter interfaced DC link rail to rail fault in a superconducting power system has only been investigated using simulation models validated by theoretical values from the literature. This paper will present the experimentally obtained fault response for a variety of different types of superconducting tape for a rail to rail DC fault. The paper will then use these as a platform to identify key trades between protection requirements and cable design, providing guidelines to enable future informed decisions to optimise hybrid propulsion electrical power system and protection design.

Optimize Resources and Help Reduce Cost of Ownership with Dell[TM] Systems Management

ERIC Educational Resources Information Center

Technology & Learning, 2008

2008-01-01

Maintaining secure, convenient administration of the PC system environment can be a significant drain on resources. Deskside visits can greatly increase the cost of supporting a large number of computers. Even simple tasks, such as tracking inventory or updating software, quickly become expensive when they require physically visiting every…

77 FR 19680 - Extension of Agency Information Collection Activity Under OMB Review: Rail Transportation Security

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-02

... receivers of certain hazardous materials; and passenger railroad carriers, including each carrier operating light rail or heavy rail transit service on track that is part of the general railroad system of transportation and rail transit systems. Also, these persons are required to report significant security concerns...

The Retirement Equity Act, Survivor Benefits Protections, and Public Employee Retirement Systems.

ERIC Educational Resources Information Center

Liebig, Phoebe S.

The Retirement Equity Act (REA) sets out requirements for joint and survivor annuity coverage for married individuals who participate in federally regulated retirement plans. REA-mandated provisions do not apply to state and local government retirement systems. Because state and local government employees constitute a significant part of the work…

Report: EPA’s Information Systems and Data Are at Risk Due to Insufficient Training of Personnel With Significant Information Security Responsibilities

EPA Pesticide Factsheets

Report #14-P-0142, March 21, 2014. The EPA places its information systems and data at risk due to an organizational structure that has not specified required duties and responsibilities to ensure personnel are trained on key information security roles.

40 CFR 1068.120 - What requirements must I follow to rebuild engines?

Code of Federal Regulations, 2012 CFR

2012-07-01

... systems for fuel metering or electronic control so that it significantly increases the service life of the... must have a reasonable technical basis for knowing that the rebuilt engine's emission control system... believe that the engine with those parts will control emissions of all pollutants at least to the same...

40 CFR 1068.120 - What requirements must I follow to rebuild engines?

Code of Federal Regulations, 2014 CFR

2014-07-01

... systems for fuel metering or electronic control so that it significantly increases the service life of the... must have a reasonable technical basis for knowing that the rebuilt engine's emission control system... believe that the engine with those parts will control emissions of all pollutants at least to the same...

40 CFR 1068.120 - What requirements must I follow to rebuild engines?

Code of Federal Regulations, 2013 CFR

2013-07-01

... systems for fuel metering or electronic control so that it significantly increases the service life of the... must have a reasonable technical basis for knowing that the rebuilt engine's emission control system... believe that the engine with those parts will control emissions of all pollutants at least to the same...

EVA Communications Avionics and Informatics

NASA Technical Reports Server (NTRS)

Carek, David Andrew

2005-01-01

The Glenn Research Center is investigating and developing technologies for communications, avionics, and information systems that will significantly enhance extra vehicular activity capabilities to support the Vision for Space Exploration. Several of the ongoing research and development efforts are described within this presentation including system requirements formulation, technology development efforts, trade studies, and operational concept demonstrations.

Multicenter Clinical Evaluation of BacT/Alert Virtuo Blood Culture System.

PubMed

Jacobs, Michael R; Mazzulli, Tony; Hazen, Kevin C; Good, Caryn E; Abdelhamed, Ayman M; Lo, Pauline; Shum, Bianche; Roman, Katharine P; Robinson, Danielle C

2017-08-01

BacT/Alert Virtuo is an advanced, automated blood culture system incorporating improved automation and an enhanced detection algorithm to shorten time to detection. A multicenter study of the investigational Virtuo system (bioMérieux, Inc., Durham, NC) compared to BacT/Alert 3D (BTA3D) for detection of bacteremia/fungemia in four bottle types, SA and FA Plus (aerobic) and SN and FN Plus (anaerobic), was performed in a clinical setting with patient samples in a matched system design clinical trial. Blood was added to paired aerobic or anaerobic bottles, with the volume in each bottle in each pair required to be ≤10 ml and with the volumes required to be within 30% of each other. Of 5,709 bottle sets (52.5% aerobic pairs and 47.5% anaerobic pairs), 430 (7.5%) were positive for bacterial or fungal growth, with 342 (6.0%) clinically significant and 83 (1.5%) contaminated. A total of 3,539 sets (62.0%) were volume compliant, with 203 sets (5.7%) clinically significant. The positivity rates for volume-compliant bottle pairs determined by the two systems were comparable, with 68.7% of clinically significant isolates detected by both instruments, 15.7% by Virtuo only, and 15.7% by BTA3D only. Virtuo detected microbial growth nearly 2 h sooner overall than BTA3D (mean, 15.9 h versus 17.7 h). Shorter time to detection by Virtuo was related to organism group, with the time to detection being significantly shorter for enteric Gram-negative bacilli and enterococci (means, 3.6 h and 2.3 h shorter, respectively). This large clinical study demonstrated that the Virtuo blood culture system produced results comparable to those seen with the long-established BTA3D system, with significantly shorter time to detection. Copyright © 2017 Jacobs et al.

Systems Analysis of GPS Electrical Power System Redesign

DTIC Science & Technology

1995-12-01

Table 8 - System Efficiencies & Multipliers for Solar Direct Model (12:102; 15:864) Component Efficiency AMTEC 0.180 Receiver and Thermal Energy Storage...and low temperatures of the working fluid. Extreme high and low temperatures provide a greater efficiency , but require extensive thermal control and...direct conversion category. The Alkali Metal Thermal -to-Electric Converter ( AMTEC ) shows mass and cost savings due to efficiencies significantly higher

An Analysis of Training Requirements and Competencies for the Naval Acquisition Systems Engineering Workforce

DTIC Science & Technology

2013-06-01

math (Lasley- Hunter, 2011, p. 30–31). The significance of this finding stems from the fact that education is one of three components of DAWIA...II CLE 003 Technical Reviews SYS 302 Technical Leadership in Systems Engineering CLL  008 Designing for Supportability in DoD Systems DAU SPRDE‐SE

Enabling Air Force Satellite Ground System Automation Through Software Engineering

DTIC Science & Technology

US Air Force satellite ground stations require significant manpower to operate due to their fragmented legacy architectures . To improve operating...daily operations, but also the development, maintainability, and the extensibility of such systems. This thesis researches challenges to Air Force...satellite automation: 1) existing architecture of legacy systems, 2) space segment diversity, and 3) unclear definition and scoping of the term, automation

Concave Surround Optics for Rapid Multi-View Imaging

DTIC Science & Technology

2006-11-01

thus is amenable to capturing dynamic events avoiding the need to construct and calibrate an array of cameras. We demonstrate the system with a high...hard to assemble and calibrate . In this paper we present an optical system capable of rapidly moving the viewpoint around a scene. Our system...flexibility, large camera arrays are typically expensive and require significant effort to calibrate temporally, geometrically and chromatically

Certification Report: Army Aviation Alternative Fuels Certification Program

DTIC Science & Technology

2016-08-01

combustion, turbine , fuel system hardware, performance system analysis, system integration, and airworthiness engage in iterative meetings and reviews...increased level of fair wear and tear. The CSI is directed at identifying possible long-term maintenance effects. 6.2.1.1 GE T700 Combustor Rig... maintenance and sustainment (supportability) impacts. FSEs can be conducted at almost any operational base but require significant coordination and a

Space construction system analysis. Part 2: Cost and programmatics

NASA Technical Reports Server (NTRS)

Vonflue, F. W.; Cooper, W.

1980-01-01

Cost and programmatic elements of the space construction systems analysis study are discussed. The programmatic aspects of the ETVP program define a comprehensive plan for the development of a space platform, the construction system, and the space shuttle operations/logistics requirements. The cost analysis identified significant items of cost on ETVP development, ground, and flight segments, and detailed the items of space construction equipment and operations.

Technical support for digital systems technology development. Task order 1: ISP contention analysis and control

NASA Technical Reports Server (NTRS)

Stehle, Roy H.; Ogier, Richard G.

1993-01-01

Alternatives for realizing a packet-based network switch for use on a frequency division multiple access/time division multiplexed (FDMA/TDM) geostationary communication satellite were investigated. Each of the eight downlink beams supports eight directed dwells. The design needed to accommodate multicast packets with very low probability of loss due to contention. Three switch architectures were designed and analyzed. An output-queued, shared bus system yielded a functionally simple system, utilizing a first-in, first-out (FIFO) memory per downlink dwell, but at the expense of a large total memory requirement. A shared memory architecture offered the most efficiency in memory requirements, requiring about half the memory of the shared bus design. The processing requirement for the shared-memory system adds system complexity that may offset the benefits of the smaller memory. An alternative design using a shared memory buffer per downlink beam decreases circuit complexity through a distributed design, and requires at most 1000 packets of memory more than the completely shared memory design. Modifications to the basic packet switch designs were proposed to accommodate circuit-switched traffic, which must be served on a periodic basis with minimal delay. Methods for dynamically controlling the downlink dwell lengths were developed and analyzed. These methods adapt quickly to changing traffic demands, and do not add significant complexity or cost to the satellite and ground station designs. Methods for reducing the memory requirement by not requiring the satellite to store full packets were also proposed and analyzed. In addition, optimal packet and dwell lengths were computed as functions of memory size for the three switch architectures.

Design of the polar neutron-imaging aperture for use at the National Ignition Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fatherley, V. E., E-mail: vef@lanl.gov; Martinez, J. I.; Merrill, F. E.

2016-11-15

The installation of a neutron imaging diagnostic with a polar view at the National Ignition Facility (NIF) required design of a new aperture, an extended pinhole array (PHA). This PHA is different from the pinhole array for the existing equatorial system due to significant changes in the alignment and recording systems. The complex set of component requirements, as well as significant space constraints in its intended location, makes the design of this aperture challenging. In addition, lessons learned from development of prior apertures mandate careful aperture metrology prior to first use. This paper discusses the PHA requirements, constraints, and themore » final design. The PHA design is complex due to size constraints, machining precision, assembly tolerances, and design requirements. When fully assembled, the aperture is a 15 mm × 15 mm × 200 mm tungsten and gold assembly. The PHA body is made from 2 layers of tungsten and 11 layers of gold. The gold layers include 4 layers containing penumbral openings, 4 layers containing pinholes and 3 spacer layers. In total, there are 64 individual, triangular pinholes with a field of view (FOV) of 200 μm and 6 penumbral apertures. Each pinhole is pointed to a slightly different location in the target plane, making the effective FOV of this PHA a 700 μm square in the target plane. The large FOV of the PHA reduces the alignment requirements both for the PHA and the target, allowing for alignment with a laser tracking system at NIF.« less

Automated CAD design for sculptured airfoil surfaces

NASA Astrophysics Data System (ADS)

Murphy, S. D.; Yeagley, S. R.

1990-11-01

The design of tightly tolerated sculptured surfaces such as those for airfoils requires a significant design effort in order to machine the tools to create these surfaces. Because of the quantity of numerical data required to describe the airfoil surfaces, a CAD approach is required. Although this approach will result in productivity gains, much larger gains can be achieved by automating the design process. This paper discusses an application which resulted in an eightfold improvement in productivity by automating the design process on the CAD system.

Individuals Achieve More Accurate Results with Meters That Are Codeless and Employ Dynamic Electrochemistry

PubMed Central

Rao, Anoop; Wiley, Meg; Iyengar, Sridhar; Nadeau, Dan; Carnevale, Julie

2010-01-01

Background Studies have shown that controlling blood glucose can reduce the onset and progression of the long-term microvascular and neuropathic complications associated with the chronic course of diabetes mellitus. Improved glycemic control can be achieved by frequent testing combined with changes in medication, exercise, and diet. Technological advancements have enabled improvements in analytical accuracy of meters, and this paper explores two such parameters to which that accuracy can be attributed. Methods Four blood glucose monitoring systems (with or without dynamic electrochemistry algorithms, codeless or requiring coding prior to testing) were evaluated and compared with respect to their accuracy. Results Altogether, 108 blood glucose values were obtained for each system from 54 study participants and compared with the reference values. The analysis depicted in the International Organization for Standardization table format indicates that the devices with dynamic electrochemistry and the codeless feature had the highest proportion of acceptable results overall (System A, 101/103). Results were significant when compared at the 10% bias level with meters that were codeless and utilized static electrochemistry (p = .017) or systems that had static electrochemistry but needed coding (p = .008). Conclusions Analytical performance of these blood glucose meters differed significantly depending on their technologic features. Meters that utilized dynamic electrochemistry and did not require coding were more accurate than meters that used static electrochemistry or required coding. PMID:20167178

Individuals achieve more accurate results with meters that are codeless and employ dynamic electrochemistry.

PubMed

Rao, Anoop; Wiley, Meg; Iyengar, Sridhar; Nadeau, Dan; Carnevale, Julie

2010-01-01

Studies have shown that controlling blood glucose can reduce the onset and progression of the long-term microvascular and neuropathic complications associated with the chronic course of diabetes mellitus. Improved glycemic control can be achieved by frequent testing combined with changes in medication, exercise, and diet. Technological advancements have enabled improvements in analytical accuracy of meters, and this paper explores two such parameters to which that accuracy can be attributed. Four blood glucose monitoring systems (with or without dynamic electrochemistry algorithms, codeless or requiring coding prior to testing) were evaluated and compared with respect to their accuracy. Altogether, 108 blood glucose values were obtained for each system from 54 study participants and compared with the reference values. The analysis depicted in the International Organization for Standardization table format indicates that the devices with dynamic electrochemistry and the codeless feature had the highest proportion of acceptable results overall (System A, 101/103). Results were significant when compared at the 10% bias level with meters that were codeless and utilized static electrochemistry (p = .017) or systems that had static electrochemistry but needed coding (p = .008). Analytical performance of these blood glucose meters differed significantly depending on their technologic features. Meters that utilized dynamic electrochemistry and did not require coding were more accurate than meters that used static electrochemistry or required coding. 2010 Diabetes Technology Society.

Optical design considerations for high-concentration photovoltaics

NASA Astrophysics Data System (ADS)

Garboushian, Vahan; Gordon, Robert

2006-08-01

Over the past 15 years, major advances in Concentrating Photovoltaics (CPV) have been achieved. Ultra-efficient Si solar cells have produced commercial concentration systems which are being fielded today and are competitively priced. Advanced research has primarily focused on significantly more efficient multi-junction solar cells for tomorrow's systems. This effort has produced sophisticated solar cells that significantly improve power production. Additional performance and cost improvements, especially in the optical system area and system integration, must be made before CPV can realize its ultimate commercial potential. Structural integrity and reliability are vital for commercial success. As incremental technical improvements are made in solar cell technologies, evaluation and 'fine-tuning' of optical systems properly matched to the solar cell are becoming increasingly necessary. As we move forward, it is increasingly important to optimize all of the interrelated elements of a CPV system for high performance without sacrificing the marketable cost and structural requirements of the system. Areas such as wavelength absorption of refractive optics need to be carefully matched to the solar cell technology employed. Reflective optics require advanced engineering models to insure uniform flux distribution without excessive losses. In Situ measurement of the 'fine-grain' improvements are difficult as multiple variables such as solar insolation, temperature, wind, altitude, etc. infringe on analytical data. This paper discusses design considerations based on 10 years of field trials of high concentration systems and their relevance for tomorrow's advanced CPV systems.

Technical and economic feasibility study of solar/fossil hybrid power systems

NASA Technical Reports Server (NTRS)

Bloomfield, H. S.; Calogeras, J. E.

1977-01-01

Results show that new hybrid systems utilizing fossil fuel augmentation of solar energy can provide significant capital and energy cost benefits when compared with solar thermal systems requiring thermal storage. These benefits accrue from a reduction of solar collection area that results from both the use of highly efficient gas and combined cycle energy conversion subsystems and elimination of the requirement for long-term energy storage subsystems. Technical feasibility and fuel savings benefits of solar hybrid retrofit to existing fossil-fired, gas and vapor cycle powerplants was confirmed; however, economic viability of steam cycle retrofit was found to be dependent on the thermodynamic and operational characteristics of the existing powerplant.

Intelligent Elements for the ISHM Testbed and Prototypes (ITP) Project

NASA Technical Reports Server (NTRS)

Maul, William A.; Park, Han; Schwabacher, Mark; Watson, Michael; Mackey, Ryan; Fijany, Amir; Trevino, Luis; Weir, John

2005-01-01

Deep-space manned missions will require advanced automated health assessment capabilities. Requirements such as in-space assembly, long dormant periods and limited accessibility during flight, present significant challenges that should be addressed through Integrated System Health Management (ISHM). The ISHM approach will provide safety and reliability coverage for a complete system over its entire life cycle by determining and integrating health status and performance information from the subsystem and component levels. This paper will focus on the potential advanced diagnostic elements that will provide intelligent assessment of the subsystem health and the planned implementation of these elements in the ISHM Testbed and Prototypes (ITP) Project under the NASA Exploration Systems Research and Technology program.

Presence of Candida Albicans in Root Canal System of Teeth Requiring Endodontic Retreatment with and without Periapical Lesions

PubMed Central

Ashraf, Hengameh; Samiee, Mohammad; Eslami, Gita; Ghodse Hosseini, Mohammad Reza

2007-01-01

INTRODUCTION: An important consideration in endodontic treatment is the elimination of microorganisms, including fungi, from the complex three- dimensional root canal system. Candida Albicans (CA) has a major role in endodontic treatment failure as the most important fungus isolated from the root canal system. The present study was carried out to evaluate the presence of CA in the teeth requiring endodontic retreatment, with or without periapical lesions. MATERIALS AND METHODS: This study was carried out on 60 root canals from human molars requiring endodontic retreatment. The root canals were randomly divided into two equal groups of 30 canals with versus without periapical lesions. Samples were collected from the root canals and cultured on MacConkey and blood agar culture media. The samples suspected of having CA were streaked on Sabouraud’s Dextrose Agar (SDA) and evaluated under a light microscope. Data was analyzed and compared using Chi- square and Kappa tests. RESULTS: CA was found in 11 patients (36.7%) with periapical lesions. In the patients without periapical lesions only 4 samples demonstrated CA in the root canal systems (13.3%). The difference between the two groups as to the presence of CA was statistically significant (p<0.037). In addition, evaluation of salivary samples revealed 15 cases (50%) of CA presence in the patients with periapical lesions and 16 cases (53.3%) of CA in the patients without periapical lesions, demonstrating no statistically significant difference between the two groups. CONCLUSION: Considering the fact that the presence of CA in the root canal systems of teeth with periapical lesions was more noticeable and statistically significant compared to the teeth without periapical lesions, the elimination of this microorganism from the root canal system, using appropriate intracanal solutions and medications is of utmost importance. PMID:24348654

The Vehicle Integrated Performance Analysis Experience: Reconnecting With Technical Integration

NASA Technical Reports Server (NTRS)

McGhee, D. S.

2006-01-01

Very early in the Space Launch Initiative program, a small team of engineers at MSFC proposed a process for performing system-level assessments of a launch vehicle. Aimed primarily at providing insight and making NASA a smart buyer, the Vehicle Integrated Performance Analysis (VIPA) team was created. The difference between the VIPA effort and previous integration attempts is that VIPA a process using experienced people from various disciplines, which focuses them on a technically integrated assessment. The foundations of VIPA s process are described. The VIPA team also recognized the need to target early detailed analysis toward identifying significant systems issues. This process is driven by the T-model for technical integration. VIPA s approach to performing system-level technical integration is discussed in detail. The VIPA process significantly enhances the development and monitoring of realizable project requirements. VIPA s assessment validates the concept s stated performance, identifies significant issues either with the concept or the requirements, and then reintegrates these issues to determine impacts. This process is discussed along with a description of how it may be integrated into a program s insight and review process. The VIPA process has gained favor with both engineering and project organizations for being responsive and insightful

Cryostatless high temperature supercurrent bearings for rocket engine turbopumps

NASA Technical Reports Server (NTRS)

Rao, Dantam K.; Dill, James F.

1989-01-01

The rocket engine systems examined include SSME, ALS, and CTV systems. The liquid hydrogen turbopumps in the SSME and ALS vehicle systems are identified as potentially attractive candidates for development of Supercurrent Bearings since the temperatures around the bearings is about 30 K, which is considerably lower than the 95 K transition temperatures of HTS materials. At these temperatures, the current HTS materials are shown to be capable of developing significantly higher current densities. This higher current density capability makes the development of supercurrent bearings for rocket engines an attractive proposition. These supercurrent bearings are also shown to offer significant advantages over conventional bearings used in rocket engines. They can increase the life and reliability over rolling element bearings because of noncontact operation. They offer lower power loss over conventional fluid film bearings. Compared to conventional magnetic bearings, they can reduce the weight of controllers significantly, and require lower power because of the use of persistent currents. In addition, four technology areas that require further attention have been identified. These are: Supercurrent Bearing Conceptual Design Verification; HTS Magnet Fabrication and Testing; Cryosensors and Controller Development; and Rocket Engine Environmental Compatibility Testing.

Confinement of gene drive systems to local populations: A comparative analysis

PubMed Central

Marshall, John M.; Hay, Bruce A.

2011-01-01

Mosquito-borne diseases such as malaria and dengue fever pose a major health problem through much of the world. One approach to disease prevention involves the use of selfish genetic elements to drive disease-refractory genes into wild mosquito populations. Recently engineered synthetic drive systems have provided encouragement for this strategy; but at the same time have been greeted with caution over the concern that transgenes may spread into countries and communities without their consent. Consequently, there is also interest in gene drive systems that, while strong enough to bring about local population replacement, are unable to establish themselves beyond a partially-isolated release site, at least during the testing phase. Here, we develop simple deterministic and stochastic models to compare the confinement properties of a variety of gene drive systems. Our results highlight several systems with desirable features for confinement – a high migration rate required to become established in neighboring populations, and low-frequency persistence in neighboring populations for moderate migration rates. Single-allele underdominance and single-locus engineered underdominance have the strongest confinement properties, but are difficult to engineer and require a high introduction frequency, respectively. Toxin-antidote systems such as Semele, Merea and two-locus engineered underdominance show promising confinement properties and require lower introduction frequencies. Killer-rescue is self-limiting in time, but is able to disperse to significant levels in neighboring populations. We discuss the significance of these results in the context of a phased release of transgenic mosquitoes, and the need for characterization of local ecology prior to a release. PMID:22094363

Transverse vs torsional ultrasound: prospective randomized contralaterally controlled study comparing two phacoemulsification-system handpieces

PubMed Central

Assil, Kerry K; Harris, Lindsay; Cecka, Jeannie

2015-01-01

Purpose To compare surgical efficiency and multiple early clinical outcome variables in eyes undergoing phacoemulsification using either transversal or torsional ultrasound systems. Setting Assil Eye Institute, Beverly Hills, CA, USA. Design Prospective, randomized, clinician-masked, contralaterally controlled single-center evaluation. Patients and methods Patients seeking cataract removal in both eyes with implantation of multifocal intraocular lenses were randomly assigned to one of two treatment rooms for phacoemulsification with either a transverse ultrasound system or torsional handpiece system. The contralateral eye was treated at a later date with the alternate device. A total of 54 eyes of 27 patients having similar degrees of cataract, astigmatism, and visual potential were included. All operative data were collected for analysis, and patients were followed for 3 months after surgery. Results Similar visual acuity was reported at all postoperative visits between the two groups. Mean phacoemulsification time and total power required were both significantly lower with the transverse system than with the torsional technique (P<0.05 for both). Similarly, mean total balanced salt solution used was significantly less with the transverse system vs torsional (P<0.05). Postoperative safety demonstrated significantly lower endothelial cell loss at 1 day and 1 month (P<0.05) with transverse vs torsional. Macular swelling was less at 1 week, 1 month, and 3 months with transverse vs torsional, although the difference did not achieve significance (P=0.1) at any single time point. Clinically detectable corneal edema was reported less frequently at all postoperative time points with the transverse system. Conclusion The transverse ultrasound system was found to be possibly associated with less balanced salt-solution use, less phacoemulsification time, and less power required than the torsional phaco system. Postoperative data suggested that improved phaco efficiency may translate to a better overall safety profile for the patient. PMID:26345628

Transceiver optics for interplanetary communications

NASA Astrophysics Data System (ADS)

Roberts, W. T.; Farr, W. H.; Rider, B.; Sampath, D.

2017-11-01

In-situ interplanetary science missions constantly push the spacecraft communications systems to support successively higher downlink rates. However, the highly restrictive mass and power constraints placed on interplanetary spacecraft significantly limit the desired bandwidth increases in going forward with current radio frequency (RF) technology. To overcome these limitations, we have evaluated the ability of free-space optical communications systems to make substantial gains in downlink bandwidth, while holding to the mass and power limits allocated to current state-of-the-art Ka-band communications systems. A primary component of such an optical communications system is the optical assembly, comprised of the optical support structure, optical elements, baffles and outer enclosure. We wish to estimate the total mass that such an optical assembly might require, and assess what form it might take. Finally, to ground this generalized study, we should produce a conceptual design, and use that to verify its ability to achieve the required downlink gain, estimate it's specific optical and opto-mechanical requirements, and evaluate the feasibility of producing the assembly.

Progress in Materials and Component Development for Advanced Lithium-ion Cells for NASA's Exploration Missions

NASA Technical Reports Server (NTRS)

Reid, Concha, M.; Reid, Concha M.

2011-01-01

Vehicles and stand-alone power systems that enable the next generation of human missions to the Moon will require energy storage systems that are safer, lighter, and more compact than current state-of-the- art (SOA) aerospace quality lithium-ion (Li-ion) batteries. NASA is developing advanced Li-ion cells to enable or enhance the power systems for the Altair Lunar Lander, Extravehicular Activities spacesuit, and rovers and portable utility pallets for Lunar Surface Systems. Advanced, high-performing materials are required to provide component-level performance that can offer the required gains at the integrated cell level. Although there is still a significant amount of work yet to be done, the present state of development activities has resulted in the synthesis of promising materials that approach the ultimate performance goals. This report on interim progress of the development efforts will elaborate on the challenges of the development activities, proposed strategies to overcome technical issues, and present performance of materials and cell components.

Driving Circuitry for Focused Ultrasound Noninvasive Surgery and Drug Delivery Applications

PubMed Central

El-Desouki, Munir M.; Hynynen, Kullervo

2011-01-01

Recent works on focused ultrasound (FUS) have shown great promise for cancer therapy. Researchers are continuously trying to improve system performance, which is resulting in an increased complexity that is more apparent when using multi-element phased array systems. This has led to significant efforts to reduce system size and cost by relying on system integration. Although ideas from other fields such as microwave antenna phased arrays can be adopted in FUS, the application requirements differ significantly since the frequency range used in FUS is much lower. In this paper, we review recent efforts to design efficient power monitoring, phase shifting and output driving techniques used specifically for high intensity focused ultrasound (HIFU). PMID:22346589

Integrated gasifier combined cycle polygeneration system to produce liquid hydrogen

NASA Technical Reports Server (NTRS)

Burns, R. K.; Staiger, P. J.; Donovan, R. M.

1982-01-01

An integrated gasifier combined cycle (IGCC) system which simultaneously produces electricity, process steam, and liquid hydrogen was evaluated and compared to IGCC systems which cogenerate electricity and process steam. A number of IGCC plants, all employing a 15 MWe has turbine and producing from 0 to 20 tons per day of liquid hydrogen and from 0 to 20 MWt of process steam were considered. The annual revenue required to own and operate such plants was estimated to be significantly lower than the potential market value of the products. The results indicate a significant potential economic benefit to configuring IGCC systems to produce a clean fuel in addition to electricity and process steam in relatively small industrial applications.

Driving circuitry for focused ultrasound noninvasive surgery and drug delivery applications.

PubMed

El-Desouki, Munir M; Hynynen, Kullervo

2011-01-01

Recent works on focused ultrasound (FUS) have shown great promise for cancer therapy. Researchers are continuously trying to improve system performance, which is resulting in an increased complexity that is more apparent when using multi-element phased array systems. This has led to significant efforts to reduce system size and cost by relying on system integration. Although ideas from other fields such as microwave antenna phased arrays can be adopted in FUS, the application requirements differ significantly since the frequency range used in FUS is much lower. In this paper, we review recent efforts to design efficient power monitoring, phase shifting and output driving techniques used specifically for high intensity focused ultrasound (HIFU).

A Knowledge-Based and Model-Driven Requirements Engineering Approach to Conceptual Satellite Design

NASA Astrophysics Data System (ADS)

Dos Santos, Walter A.; Leonor, Bruno B. F.; Stephany, Stephan

Satellite systems are becoming even more complex, making technical issues a significant cost driver. The increasing complexity of these systems makes requirements engineering activities both more important and difficult. Additionally, today's competitive pressures and other market forces drive manufacturing companies to improve the efficiency with which they design and manufacture space products and systems. This imposes a heavy burden on systems-of-systems engineering skills and particularly on requirements engineering which is an important phase in a system's life cycle. When this is poorly performed, various problems may occur, such as failures, cost overruns and delays. One solution is to underpin the preliminary conceptual satellite design with computer-based information reuse and integration to deal with the interdisciplinary nature of this problem domain. This can be attained by taking a model-driven engineering approach (MDE), in which models are the main artifacts during system development. MDE is an emergent approach that tries to address system complexity by the intense use of models. This work outlines the use of SysML (Systems Modeling Language) and a novel knowledge-based software tool, named SatBudgets, to deal with these and other challenges confronted during the conceptual phase of a university satellite system, called ITASAT, currently being developed by INPE and some Brazilian universities.

Alternate-Fueled Combustor-Sector Performance: Part A: Combustor Performance Part B: Combustor Emissions

NASA Technical Reports Server (NTRS)

Shouse, D. T.; Neuroth, C.; Henricks, R. C.; Lynch, A.; Frayne, C.; Stutrud, J. S.; Corporan, E.; Hankins, T.

2010-01-01

Alternate aviation fuels for military or commercial use are required to satisfy MIL-DTL-83133F(2008) or ASTM D 7566 (2010) standards, respectively, and are classified as drop-in fuel replacements. To satisfy legacy issues, blends to 50% alternate fuel with petroleum fuels are certified individually on the basis of feedstock. Adherence to alternate fuels and fuel blends requires smart fueling systems or advanced fuel-flexible systems, including combustors and engines without significant sacrifice in performance or emissions requirements. This paper provides preliminary performance (Part A) and emissions and particulates (Part B) combustor sector data for synthetic-parafinic-kerosene- (SPK-) type fuel and blends with JP-8+100 relative to JP-8+100 as baseline fueling.

Atmospheric rendezvous feasibility study

NASA Technical Reports Server (NTRS)

Schaezler, A. D.

1972-01-01

A study was carried out to determine the feasibility of using atmospheric rendezvous to increase the efficiency of space transportation and to determine the most effective implementation. It is concluded that atmospheric rendezvous is feasible and can be utilized in a space transportation system to reduce size of the orbiter vehicle, provide a powered landing with go-around capability for every mission, and achieve lateral range performance that exceeds requirements. A significantly lighter booster and reduced launch fuel requirements are additional benefits that can be realized with a system that includes a large subsonic airplane for recovery of the orbiter. Additional reduction in booster size is possible if the airplane is designed for recovery of the booster by towing. An airplane about the size of the C-5A is required.

Defining Support Requirements During Conceptual Design of Reusable Launch Vehicles

NASA Technical Reports Server (NTRS)

Morris, W. D.; White, N. H.; Davis, W. T.; Ebeling, C. E.

1995-01-01

Current methods for defining the operational support requirements of new systems are data intensive and require significant design information. Methods are being developed to aid in the analysis process of defining support requirements for new launch vehicles during their conceptual design phase that work with the level of information available during this phase. These methods will provide support assessments based on the vehicle design and the operating scenarios. The results can be used both to define expected support requirements for new launch vehicle designs and to help evaluate the benefits of using new technologies. This paper describes the models, their current status, and provides examples of their use.

Tornado wind-loading requirements based on risk assessment techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deobald, T.L.; Coles, G.A.; Smith, G.L.

Regulations require that nuclear power plants be protected from tornado winds. If struck by a tornado, a plant must be capable of safely shutting down and removing decay heat. Probabilistic techniques are used to show that risk to the public from the US Department of Energy (DOE) SP-100 reactor is acceptable without tornado hardening parts of the secondary system. Relaxed requirements for design wind loadings will result in significant cost savings. To demonstrate an acceptable level of risk, this document examines tornado-initiated accidents. The two tornado-initiated accidents examined in detail are loss of cooling resulting in core damage and lossmore » of secondary system boundary integrity leading to sodium release. Loss of core cooling is analyzed using fault/event tree models. Loss of secondary system boundary integrity is analyzed by comparing the consequences to acceptance criteria for the release of radioactive material or alkali metal aerosol. 4 refs., 4 figs.« less

Extended duration Orbiter life support definition

NASA Technical Reports Server (NTRS)

Kleiner, G. N.; Thompson, C. D.

1978-01-01

Extending the baseline seven-day Orbiter mission to 30 days or longer and operating with a solar power module as the primary source for electrical power requires changes to the existing environmental control and life support (ECLS) system. The existing ECLS system imposes penalties on longer missions which limit the Orbiter capabilities and changes are required to enhance overall mission objectives. Some of these penalties are: large quantities of expendables, the need to dump or store large quantities of waste material, the need to schedule fuel cell operation, and a high landing weight penalty. This paper presents the study ground rules and examines the limitations of the present ECLS system against Extended Duration Orbiter mission requirements. Alternate methods of accomplishing ECLS functions for the Extended Duration Orbiter are discussed. The overall impact of integrating these options into the Orbiter are evaluated and significant Orbiter weight and volume savings with the recommended approaches are described.

CVT/PCS phase 1 integrated testing

NASA Technical Reports Server (NTRS)

Mcbrayer, R. O.; Steadman, J. D.

1973-01-01

Five breadboard experiments representing three Sortie Lab experiment disciplines were installed in a payload carrier simulator. A description of the experiments and the payload carrier simulator was provided. An assessment of the experiment interface with the simulator and an assessment of the simulator experiment support systems were presented. The results indicate that a hardware integrator for each experiment is essential; a crew chief, or mission specialist, for systems management and experimenter liaison is a vital function; a payload specialist is a practical concept for experiment integration and operation; an integration fixture for a complex experiment is required to efficiently integrate the experiment and carrier; simultaneous experiment utilization of simulator systems caused unexpected problems in meeting individual experiment requirements; experimenter traffic inside the dual-floor simulator did not hamper experiment operations; and the requirement for zero-g operation will provide a significant design challenge for some experiments.

Potential end-to-end imaging information rate advantages of various alternative communication systems

NASA Technical Reports Server (NTRS)

Rice, R. F.

1978-01-01

Various communication systems were considered which are required to transmit both imaging and a typically error sensitive, class of data called general science/engineering (gse) over a Gaussian channel. The approach jointly treats the imaging and gse transmission problems, allowing comparisons of systems which include various channel coding and data compression alternatives. Actual system comparisons include an Advanced Imaging Communication System (AICS) which exhibits the rather significant potential advantages of sophisticated data compression coupled with powerful yet practical channel coding.

NASA's Nuclear Thermal Propulsion Project

NASA Technical Reports Server (NTRS)

Houts, Mike; Mitchell, Sonny; Kim, Tony; Borowski, Stan; Power, Kevin; Scott, John; Belvin, Anthony; Clement, Steve

2015-01-01

HEOMD's (Human Exploration and Operations Mission Directorate) AES (Advanced Exploration Systems) Nuclear Thermal Propulsion (NTP) project is making significant progress. First of four FY 2015 milestones achieved this month. Safety is the highest priority for NTP (as with other space systems). After safety comes affordability. No centralized capability for developing, qualifying, and utilizing an NTP system. Will require a strong, closely integrated team. Tremendous potential benefits from NTP and other space fission systems. No fundamental reason these systems cannot be developed and utilized in a safe, affordable fashion.

Solid Oxide Fuel Cell Development for Auxiliary Power in Heavy Duty Vehicle Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daniel T. Hennessy

2010-06-15

Changing economic and environmental needs of the trucking industry is driving the use of auxiliary power unit (APU) technology for over the road haul trucks. The trucking industry in the United States remains the key to the economy of the nation and one of the major changes affecting the trucking industry is the reduction of engine idling. Delphi Automotive Systems, LLC (Delphi) teamed with heavy-duty truck Original Equipment Manufacturers (OEMs) PACCAR Incorporated (PACCAR), and Volvo Trucks North America (VTNA) to define system level requirements and develop an SOFC based APU. The project defines system level requirements, and subsequently designs andmore » implements an optimized system architecture using an SOFC APU to demonstrate and validate that the APU will meet system level goals. The primary focus is on APUs in the range of 3-5 kW for truck idling reduction. Fuels utilized were derived from low-sulfur diesel fuel. Key areas of study and development included sulfur remediation with reformer operation; stack sensitivity testing; testing of catalyst carbon plugging and combustion start plugging; system pre-combustion; and overall system and electrical integration. This development, once fully implemented and commercialized, has the potential to significantly reduce the fuel idling Class 7/8 trucks consume. In addition, the significant amounts of NOx, CO2 and PM that are produced under these engine idling conditions will be virtually eliminated, inclusive of the noise pollution. The environmental impact will be significant with the added benefit of fuel savings and payback for the vehicle operators / owners.« less

Space shuttle avionics system

NASA Technical Reports Server (NTRS)

Hanaway, John F.; Moorehead, Robert W.

1989-01-01

The Space Shuttle avionics system, which was conceived in the early 1970's and became operational in the 1980's represents a significant advancement of avionics system technology in the areas of systems and redundacy management, digital data base technology, flight software, flight control integration, digital fly-by-wire technology, crew display interface, and operational concepts. The origins and the evolution of the system are traced; the requirements, the constraints, and other factors which led to the final configuration are outlined; and the functional operation of the system is described. An overall system block diagram is included.

Dump system concepts for the Future Circular Collider

NASA Astrophysics Data System (ADS)

Bartmann, W.; Atanasov, M.; Barnes, M. J.; Borburgh, J.; Burkart, F.; Goddard, B.; Kramer, T.; Lechner, A.; Ull, A. Sanz; Schmidt, R.; Stoel, L. S.; Ostojic, R.; Rodziewicz, J.; van Trappen, P.; Barna, D.

2017-03-01

The Future Circular Collider (FCC-hh) beam dump system must provide a safe and reliable extraction and dilution of the stored beam onto a dump absorber. Energy deposition studies show that damage limits of presently used absorber materials will already be reached for single bunches at 50 TeV. A fast field rise of the extraction kicker is required in order to sufficiently separate swept single bunches on the extraction protection absorbers in case of an asynchronous beam dump. In line with this demand is the proposal of a highly segmented extraction kicker system which allows for accepting a single kicker switch erratic and thus, significantly reduces the probability of an asynchronous beam dump. Superconducting septa are foreseen to limit the overall system length and power consumption. Two extraction system concepts are presented and evaluated regarding overall system length, energy deposition on absorbers, hardware requirements, radiation issues, and layout flexibility.

US Navy SHF SATCOM: Past, present and future

NASA Astrophysics Data System (ADS)

Bushnell, Christopher J.

1994-06-01

This thesis discusses the Navy's Super High Frequency Satellite Communications (SHF SATCOM) capabilities prior to Desert Shield/Desert Storm, and the requirements for future systems that were generated due to Navy SATCOM shortcomings during the Gulf War. The four-phased evolutionary approach the Navy has designed (based on post-war requirements) to provide itself with a medium for SHF SATCOM into the 21st Century, as well as the Defense Satellite Communications Systems (DSCS), are examined in detail. Decreasing defense budgets have begun to have a significant impact on future military satellite communication (MILSATCOM) systems. A cost comparison between utilization of DSCS III satellites and the INMARSAT commercial SATCOM system is presented. Recommended improvements to current MILSATCOM procedures and training practices are proposed that could improve operational C4I capabilities. Finally, this study determines that future SATCOM architectures should include a mixture of commercial systems and MILSATCOM systems to provide both cost savings and command and control protection.

Overcoming barriers to electronic medical record (EMR) implementation in the US healthcare system: A comparative study.

PubMed

Kumar, Sameer; Aldrich, Krista

2010-12-01

An EMR system implementation would significantly reduce clinician workload and medical errors while saving the US healthcare system major expense. Yet, compared to other developed nations, the US lags behind. This article examines EMR system efforts, benefits, and barriers, as well as steps needed to move the US closer to a nationwide EMR system. The analysis includes a blueprint for implementation of EMR, industry comparisons to highlight the differences between successful and non-successful EMR ventures, references to costs and benefit information, and identification of root causes. 'Poka-yokes' (avoid (yokeru) mistakes (poka)) will be inserted to provide insight into how to systematically overcome challenges. Implementation will require upfront costs including patient privacy that must be addressed early in the development process. Government structure, incentives and mandates are required for nationwide EMR system in the US.

Energy Savings by Treating Buildings as Systems

NASA Astrophysics Data System (ADS)

Harvey, L. D. Danny

2008-09-01

This paper reviews the opportunities for dramatically reducing energy use in buildings by treating buildings as systems, rather than focusing on device efficiencies. Systems-level considerations are relevant for the operation of heat pumps (where the temperatures at which heat or coldness are distributed are particularly important); the joint or separate provision of heating, cooling, and ventilation; the joint or separate removal of sensible heat and moisture; and in the operation of fluid systems having pumps. Passive heating, cooling, and ventilation, as well as daylighting (use of sunlight for lighting purposes) also require consideration of buildings as systems. In order to achieve the significant (50-75%) energy savings that are possible through a systems approach, the design process itself has to involve a high degree of integration between the architect and various engineering disciplines (structural, mechanical, electrical), and requires the systematic examination and adjustment of alternative designs using computer simulation models.

Development of the Cassini Ground Data System in a multimission environment

NASA Technical Reports Server (NTRS)

Madrid, G.; Wanczuk, G.

1993-01-01

As baselined, the Cassini Ground Data System (GDS) will be composed of Project specific and multimission elements. The former will be developed by the Cassini Project and the latter by two JPL institutional organizations, the Telecommunications and Data Acquisition Office (TDA) and the Multimission Operations Systems Office (MOSO). The GDS will be developed in three principal phases: Spacecraft Test, Launch-cruise, and Science Tour, with a significant part of the development deferred until the post-launch period. New capabilities are being introduced that are key to the achievement of more cost effective operations. Successful development of the system will require careful planning and will involve participation of diverse disciplines. This paper introduces the Cassini Project from the Ground Data System perspective and discusses development approaches expected to produce systems which meet functional and performance requirements and which will be delivered on schedule and within budget.

Acoustic Biometric System Based on Preprocessing Techniques and Linear Support Vector Machines

PubMed Central

del Val, Lara; Izquierdo-Fuente, Alberto; Villacorta, Juan J.; Raboso, Mariano

2015-01-01

Drawing on the results of an acoustic biometric system based on a MSE classifier, a new biometric system has been implemented. This new system preprocesses acoustic images, extracts several parameters and finally classifies them, based on Support Vector Machine (SVM). The preprocessing techniques used are spatial filtering, segmentation—based on a Gaussian Mixture Model (GMM) to separate the person from the background, masking—to reduce the dimensions of images—and binarization—to reduce the size of each image. An analysis of classification error and a study of the sensitivity of the error versus the computational burden of each implemented algorithm are presented. This allows the selection of the most relevant algorithms, according to the benefits required by the system. A significant improvement of the biometric system has been achieved by reducing the classification error, the computational burden and the storage requirements. PMID:26091392

Acoustic Biometric System Based on Preprocessing Techniques and Linear Support Vector Machines.

PubMed

del Val, Lara; Izquierdo-Fuente, Alberto; Villacorta, Juan J; Raboso, Mariano

2015-06-17

Drawing on the results of an acoustic biometric system based on a MSE classifier, a new biometric system has been implemented. This new system preprocesses acoustic images, extracts several parameters and finally classifies them, based on Support Vector Machine (SVM). The preprocessing techniques used are spatial filtering, segmentation-based on a Gaussian Mixture Model (GMM) to separate the person from the background, masking-to reduce the dimensions of images-and binarization-to reduce the size of each image. An analysis of classification error and a study of the sensitivity of the error versus the computational burden of each implemented algorithm are presented. This allows the selection of the most relevant algorithms, according to the benefits required by the system. A significant improvement of the biometric system has been achieved by reducing the classification error, the computational burden and the storage requirements.

New Directions in Space Operations Services in Support of Interplanetary Exploration

NASA Technical Reports Server (NTRS)

Bradford, Robert N.

2005-01-01

To gain access to the necessary operational processes and data in support of NASA's Lunar/Mars Exploration Initiative, new services, adequate levels of computing cycles and access to myriad forms of data must be provided to onboard spacecraft and ground based personnel/systems (earth, lunar and Martian) to enable interplanetary exploration by humans. These systems, cycles and access to vast amounts of development, test and operational data will be required to provide a new level of services not currently available to existing spacecraft, on board crews and other operational personnel. Although current voice, video and data systems in support of current space based operations has been adequate, new highly reliable and autonomous processes and services will be necessary for future space exploration activities. These services will range from the more mundane voice in LEO to voice in interplanetary travel which because of the high latencies will require new voice processes and standards. New services, like component failure predictions based on data mining of significant quantities of data, located at disparate locations, will be required. 3D or holographic representation of onboard components, systems or family members will greatly improve maintenance, operations and service restoration not to mention crew morale. Current operational systems and standards, like the Internet Protocol, will not able to provide the level of service required end to end from an end point on the Martian surface like a scientific instrument to a researcher at a university. Ground operations whether earth, lunar or Martian and in flight operations to the moon and especially to Mars will require significant autonomy that will require access to highly reliable processing capabilities, data storage based on network storage technologies. Significant processing cycles will be needed onboard but could be borrowed from other locations either ground based or onboard other spacecraft. Reliability will be a key factor with onboard and distributed backup processing an absolutely necessary requirement. Current cluster processing/Grid technologies may provide the basis for providing these services. An overview of existing services, future services that will be required and the technologies and standards required to be developed will be presented. The purpose of this paper will be to initiate a technological roadmap, albeit at a high level, of current voice, video, data and network technologies and standards (which show promise for adaptation or evolution) to what technologies and standards need to be redefined, adjusted or areas where new ones require development. The roadmap should begin the differentiation between non manned and manned processes/services where applicable. The paper will be based in part on the activities of the CCSDS Monitor and Control working group which is beginning the process of standardization of the these processes. Another element of the paper will be based on an analysis of current technologies supporting space flight processes and services at JSC, MSFC, GSFC and to a lesser extent at KSC. Work being accomplished in areas such as Grid computing, data mining and network storage at ARC, IBM and the University of Alabama at Huntsville will be researched and analyzed.

Uses of communication satellites in water utility operations

NASA Astrophysics Data System (ADS)

Tighe, W. S.

This paper proposes a system to serve the communications needs of the operating side of a water utility and estimates the requirements and capabilities of the equipment needed. The system requires the shared use of a satellite transponder with 100% backup. Messages consist of data packets containing data and control information, plus voice transmission. Satellite communication may have a price advantage in some instances over wire line or VHF radio and have greater survivability in case of a natural disaster. Water and other utilities represent a significant market for low cost mass produced satellite earth terminals.

Strategic Adaptation of SCA for STRS

NASA Technical Reports Server (NTRS)

Quinn, Todd; Kacpura, Thomas

2007-01-01

The Space Telecommunication Radio System (STRS) architecture is being developed to provide a standard framework for future NASA space radios with greater degrees of interoperability and flexibility to meet new mission requirements. The space environment imposes unique operational requirements with restrictive size, weight, and power constraints that are significantly smaller than terrestrial-based military communication systems. With the harsh radiation environment of space, the computing and processing resources are typically one or two generations behind current terrestrial technologies. Despite these differences, there are elements of the SCA that can be adapted to facilitate the design and implementation of the STRS architecture.

Space Station solar water heater

NASA Technical Reports Server (NTRS)

Horan, D. C.; Somers, Richard E.; Haynes, R. D.

1990-01-01

The feasibility of directly converting solar energy for crew water heating on the Space Station Freedom (SSF) and other human-tended missions such as a geosynchronous space station, lunar base, or Mars spacecraft was investigated. Computer codes were developed to model the systems, and a proof-of-concept thermal vacuum test was conducted to evaluate system performance in an environment simulating the SSF. The results indicate that a solar water heater is feasible. It could provide up to 100 percent of the design heating load without a significant configuration change to the SSF or other missions. The solar heater system requires only 15 percent of the electricity that an all-electric system on the SSF would require. This allows a reduction in the solar array or a surplus of electricity for onboard experiments.

Laser-based firing systems for prompt initiation of secondary explosives

NASA Technical Reports Server (NTRS)

Meeks, Kent D.; Setchell, Robert E.

1993-01-01

Motivated by issues of weapon safety and security, laser based firing systems for promptly initiating secondary explosives have been under active development at Sandia National Laboratories for more than four years. Such a firing system consists of miniaturized, Q-switched, solid-state laser, optical detonators, optical safety switches, and elements for splitting, coupling, and transmitting the laser output. Potential system applications pose significant challenges in terms of server mechanical and thermal environments and packaging constraints, while requiring clear demonstration of safety enhancements. The Direct Optical Initiation (DOI) Program at Sandia is addressing these challenges through progress development phases during which the design, fabrication, and testing of prototype hardware is aimed at more difficult application requirements. A brief history of the development program, and a summary of current and planned activities, will be presented.

A cryogen-free ultralow-field superconducting quantum interference device magnetic resonance imaging system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eom, Byeong Ho; Penanen, Konstantin; Hahn, Inseob, E-mail: ihahn@caltech.edu

2014-09-15

Magnetic resonance imaging (MRI) at microtesla fields using superconducting quantum interference device (SQUID) detection has previously been demonstrated, and advantages have been noted. Although the ultralow-field SQUID MRI technique would not need the heavy superconducting magnet of conventional MRI systems, liquid helium required to cool the low-temperature detector still places a significant burden on its operation. We have built a prototype cryocooler-based SQUID MRI system that does not require a cryogen. The SQUID detector and the superconducting gradiometer were cooled down to 3.7 K and 4.3 K, respectively. We describe the prototype design, characterization, a phantom image, and areas ofmore » further improvements needed to bring the imaging performance to parity with conventional MRI systems.« less

Fracture Toughness, Mechanical Property, And Chemical Characterization Of A Critical Modification To The NASA SLS Solid Booster Internal Material System

NASA Technical Reports Server (NTRS)

Pancoast, Justin; Garrett, William; Moe, Gulia

2015-01-01

A modified propellant-liner-insulation (PLI) bondline in the Space Launch System (SLS) solid rocket booster required characterization for flight certification. The chemical changes to the PLI bondline and the required additional processing have been correlated to mechanical responses of the materials across the bondline. Mechanical properties testing and analyses included fracture toughness, tensile, and shear tests. Chemical properties testing and analyses included Fourier transform infrared (FTIR) spectroscopy, cross-link density, high-performance liquid chromatography (HPLC), gas chromatography (GC), gel permeation chromatography (GPC), and wave dispersion X-ray fluorescence (WDXRF). The testing identified the presence of the expected new materials and found the functional bondline performance of the new PLI system was not significantly changed from the old system.

NASA's advanced space transportation system launch vehicles

NASA Technical Reports Server (NTRS)

Branscome, Darrell R.

1991-01-01

Some insight is provided into the advanced transportation planning and systems that will evolve to support long term mission requirements. The general requirements include: launch and lift capacity to low earth orbit (LEO); space based transfer systems for orbital operations between LEO and geosynchronous equatorial orbit (GEO), the Moon, and Mars; and Transfer vehicle systems for long duration deep space probes. These mission requirements are incorporated in the NASA Civil Needs Data Base. To accomplish these mission goals, adequate lift capacity to LEO must be available: to support science and application missions; to provide for construction of the Space Station Freedom; and to support resupply of personnel and supplies for its operations. Growth in lift capacity must be time phased to support an expanding mission model that includes Freedom Station, the Mission to Planet Earth, and an expanded robotic planetary program. The near term increase in cargo lift capacity associated with development of the Shuttle-C is addressed. The joint DOD/NASA Advanced Launch System studies are focused on a longer term new cargo capability that will significantly reduce costs of placing payloads in space.

Standards Advisor-Advanced Information Technology for Advanced Information Delivery

NASA Technical Reports Server (NTRS)

Hawker, J. Scott

2003-01-01

Developers of space systems must deal with an increasing amount of information in responding to extensive requirements and standards from numerous sources. Accessing these requirements and standards, understanding them, comparing them, negotiating them and responding to them is often an overwhelming task. There are resources to aid the space systems developer, such as lessons learned and best practices. Again, though, accessing, understanding, and using this information is often more difficult than helpful. This results in space systems that: 1. Do not meet all their requirements. 2. Do not incorporate prior engineering experience. 3. Cost more to develop. 4. Take longer to develop. The NASA Technical Standards Program (NTSP) web site at http://standards.nasa.gov has made significant improvements in making standards, lessons learned, and related material available to space systems developers agency-wide. The Standards Advisor was conceived to take the next steps beyond the current product, continuing to apply evolving information technology that continues to improve information delivery to space systems developers. This report describes the features of the Standards Advisor and suggests a technical approach to its development.

NASA Growth Space Station missions and candidate nuclear/solar power systems

NASA Technical Reports Server (NTRS)

Heller, Jack A.; Nainiger, Joseph J.

1987-01-01

A brief summary is presented of a NASA study contract and in-house investigation on Growth Space Station missions and appropriate nuclear and solar space electric power systems. By the year 2000 some 300 kWe will be needed for missions and housekeeping power for a 12 to 18 person Station crew. Several Space Station configurations employing nuclear reactor power systems are discussed, including shielding requirements and power transmission schemes. Advantages of reactor power include a greatly simplified Station orientation procedure, greatly reduced occultation of views of the earth and deep space, near elimination of energy storage requirements, and significantly reduced station-keeping propellant mass due to very low drag of the reactor power system. The in-house studies of viable alternative Growth Space Station power systems showed that at 300 kWe a rigid silicon solar cell array with NiCd batteries had the highest specific mass at 275 kg/kWe, with solar Stirling the lowest at 40 kg/kWe. However, when 10 year propellant mass requirements are factored in, the 300 kWe nuclear Stirling exhibits the lowest total mass.

Evaluating the usability of speech recognition to create clinical documentation using a commercial electronic health record.

PubMed

Hodgson, Tobias; Magrabi, Farah; Coiera, Enrico

2018-05-01

To conduct a usability study exploring the value of using speech recognition (SR) for clinical documentation tasks within an electronic health record (EHR) system. Thirty-five emergency department clinicians completed a system usability scale (SUS) questionnaire. The study was undertaken after participants undertook randomly allocated clinical documentation tasks using keyboard and mouse (KBM) or SR. SUS scores were analyzed and the results with KBM were compared to SR results. Significant difference in SUS scores between EHR system use with and without SR were observed (KBM 67, SR 61; P = 0.045; CI, 0.1 to 12.0). Nineteen of 35 participants scored higher for EHR with KBM, 11 higher for EHR with SR and 5 gave the same score for both. Factor analysis showed no significant difference in scores for the sub-element of usability (EHR with KBM 65, EHR with SR 62; P = 0.255; CI, -2.6 to 9.5). Scores for the sub-element of learnability were significantly different (KBM 72, SR 55; P < 0.001; CI, 9.8 to 23.5). A significant correlation was found between the perceived usability of the two system configurations (EHR with KBM or SR) and the efficiency of documentation (time to document) (P = 0.002; CI, 10.5 to -0.1) but not with safety (number of errors) (P = 0.90; CI, -2.3 to 2.6). SR was associated with significantly reduced overall usability scores, even though it is often positioned as ease of use technology. SR was perceived to impose larger costs in terms of learnability via training and support requirements for EHR based documentation when compared to using KBM. Lower usability scores were significantly associated with longer documentation times. The usability of EHR systems with any input modality is an area that requires continued development. The addition of an SR component to an EHR system may cause a significant reduction in terms of perceived usability by clinicians. Copyright © 2018 Elsevier B.V. All rights reserved.

Power conversion distribution system using a resonant high-frequency AC link

NASA Technical Reports Server (NTRS)

Sood, P. K.; Lipo, T. A.

1986-01-01

Static power conversion systems based on a resonant high frequency (HF) link offers a significant reduction in the size and weight of the equipment over that achieved with conventional approaches, especially when multiple sources and loads are to be integrated. A faster system response and absence of audible noise are the other principal characteristics of such systems. A conversion configuration based on a HF link which is suitable for applications requiring distributed power is proposed.

Citrus Inventory

NASA Technical Reports Server (NTRS)

1986-01-01

Florida's Charlotte County Property Appraiser is using an aerial color infrared mapping system for inventorying citrus trees for valuation purposes. The ACIR system has significantly reduced the time and manpower required for appraisal. Aerial photographs are taken and interpreted by a video system which makes it possible to detect changes from previous years. Potential problems can be identified. KSC's TU Office has awarded a contract to the Citrus Research and Education Center to adapt a prototype system which would automatically count trees and report totals.

The Use of a UNIX-Based Workstation in the Information Systems Laboratory

DTIC Science & Technology

1989-03-01

system. The conclusions of the research and the resulting recommendations are presented in Chapter III. These recommendations include how to manage...required to run the program on a new system, these should not be significant changes. 2. Processing Environment The UNIX processing environment is...interactive with multi-tasking and multi-user capabilities. Multi-tasking refers to the fact that many programs can be run concurrently. This capability

Apollo experience report guidance and control systems: Lunar module abort guidance system

NASA Technical Reports Server (NTRS)

Kurten, P. M.

1975-01-01

The history of a unique development program that produced an operational fixed guidance system of inertial quality is presented. Each phase of development, beginning with requirement definition and concluding with qualification and testing, is addressed, and developmental problems are emphasized. Software generation and mission operations are described, and specifications for the inertial reference unit are included, as are flight performance results. Significant program observations are noted.

Distributed Information System Development: Review of Some Management Issues

NASA Astrophysics Data System (ADS)

Mishra, Deepti; Mishra, Alok

Due to the proliferation of the Internet and globalization, distributed information system development is becoming popular. In this paper we have reviewed some significant management issues like process management, project management, requirements management and knowledge management issues which have received much attention in distributed development perspective. In this literature review we found that areas like quality and risk management issues could get only scant attention in distributed information system development.

Improved methods for venous access: the Port-A-Cath, a totally implanted catheter system.

PubMed

Strum, S; McDermed, J; Korn, A; Joseph, C

1986-04-01

We prospectively evaluated the performance and rate of long-term complications with the Port-A-Cath (PAC), a totally implanted vascular access system. Two catheter styles were evaluated, a small-bore (SB) catheter (0.51-mm diameter) and a large-bore (LB) catheter (1.02-mm diameter), in conjunction with the use of a strict catheter care protocol. The PAC performed well, and with both SB and LB systems, no significant extravasation, skin necrosis, hematoma, septum damage or leakage, or subcutaneous portal infections occurred after 7,240 days of implantation and 1,435 days of use. Complications with the PAC system consisted of catheter occlusion (seven patients, 21.5%) and one instance of possible catheter infection (3.1%). Occlusions were limited to patients implanted with the SB catheter (seven of 16, 43.8%), and five of the seven (71.4%) occurred in patients receiving continuous infusion chemotherapy and/or total parenteral nutrition. Patency of the PAC system was maintained using a regular flushing schedule once every 30 days, a significant advantage compared with the daily maintenance schedule required with externally placed venous catheters. The results of this study suggest that the PAC system can provide a safe and reliable method for venous access in patients requiring intermittent or prolonged intravenous therapy.

Nuclear thermal propulsion transportation systems for lunar/Mars exploration

NASA Technical Reports Server (NTRS)

Clark, John S.; Borowski, Stanley K.; Mcilwain, Melvin C.; Pellaccio, Dennis G.

1992-01-01

Nuclear thermal propulsion technology development is underway at NASA and DoE for Space Exploration Initiative (SEI) missions to Mars, with initial near-earth flights to validate flight readiness. Several reactor concepts are being considered for these missions, and important selection criteria will be evaluated before final selection of a system. These criteria include: safety and reliability, technical risk, cost, and performance, in that order. Of the concepts evaluated to date, the Nuclear Engine for Rocket Vehicle Applications (NERVA) derivative (NDR) is the only concept that has demonstrated full power, life, and performance in actual reactor tests. Other concepts will require significant design work and must demonstrate proof-of-concept. Technical risk, and hence, development cost should therefore be lowest for the concept, and the NDR concept is currently being considered for the initial SEI missions. As lighter weight, higher performance systems are developed and validated, including appropriate safety and astronaut-rating requirements, they will be considered to support future SEI application. A space transportation system using a modular nuclear thermal rocket (NTR) system for lunar and Mars missions is expected to result in significant life cycle cost savings. Finally, several key issues remain for NTR's, including public acceptance and operational issues. Nonetheless, NTR's are believed to be the 'next generation' of space propulsion systems - the key to space exploration.

Ecological Processes of Isolated Wetlands: Ecosystem Services and the Significant Nexus (Invited)

NASA Astrophysics Data System (ADS)

Lane, C.; Autrey, B.; D'Amico, E.

2013-12-01

Geographically isolated wetlands occur throughout the US and are characterized by a wetland system completely surrounded by uplands. Examples include prairie potholes, woodland seasonal (i.e., vernal) pools, cypress domes, playas, and other such systems. Decisions by the US Supreme Court in 2001 and 2006 have affected the jurisdictional status of geographically isolated wetlands such that those failing to have a demonstrable 'significant nexus' to navigable waters may have no federal protection under the Clean Water Act. These systems are typically small and, as such, may be under-counted in assessments of area and abundance. Areal extent is a portion of the information required to characterize the functions associated with geographically isolated wetlands and understanding both site-specific and larger-scale processes are also required to better quantify those functions. In addition, quantifying anthropogenic effects on system processing informs our understanding of the contributions and the connectivity of geographically isolated wetlands to other waters. This presentation focuses on both efforts to quantify the contribution of geographically isolated wetlands to system-scale processes, focusing on nutrient assimilation and hydrologic storage, as well as concurrent research to identify their locations at multiple scales. Findings from this research may help elucidate the link between geographically isolated wetlands and other systems, and may inform discussions on ecosystem services provided by geographically isolated wetlands.

Improving striping operations through system optimization.

DOT National Transportation Integrated Search

2015-09-01

Striping operations generate a significant workload for Missouri Department of Transportation (MoDOT) maintenance : operations. The requirement for each striping crew to replenish its stock of paint and other consumable items from a bulk storage : fa...

Cooling vest

NASA Technical Reports Server (NTRS)

Kosmo, J.; Kane, J.; Coverdale, J.

1977-01-01

Inexpensive vest of heat-sealable urethane material, when strapped to person's body, presents significant uncomplicated cooling system for environments where heavy accumulation of metabolic heat exists. Garment is applicable to occupations where physical exertion is required under heavy protective clothing.

Center of Excellence for Hypersonics Research

DTIC Science & Technology

2012-01-25

detailed simulations of actual combustor configurations, and ultimately for the optimization of hypersonic air - breathing propulsion system flow paths... vehicle development programs. The Center engaged leading experts in experimental and computational analysis of hypersonic flows to provide research...advanced hypersonic vehicles and space access systems will require significant advances in the design methods and ground testing techniques to ensure

Aspirations of and Realities for Hong Kong Students: Is the "Formal" Transition System Effective?

ERIC Educational Resources Information Center

Pavlova, Margarita

2017-01-01

School to work transition is an important aspect of lifelong learning that has increased in significance as the knowledge-based economy takes off in developed countries. Rapid structural economic changes, the importance of innovation, and a shorter lifecycle of products require education systems to adjust to the needs of economies and individuals.…

School-Finance Reform: Inspiration and Progress in Colorado

ERIC Educational Resources Information Center

Herman, Juliana

2013-01-01

This report takes a look at Colorado's redesigned school-funding system whose fate was decided by Coloradan voters in Fall 2013. Voters were asked to approve a $1.1 billion tax increase to finance Colorado's schools, an approval required for the funding reforms to kick in. The proposed system represented a significant step forward in the push for…

A Proposal of a Color Music Notation System on a Single Melody for Music Beginners

ERIC Educational Resources Information Center

Kuo, Yi-Ting; Chuang, Ming-Chuen

2013-01-01

Music teachers often encounter obstructions in teaching beginners in music reading. Conventional notational symbols require beginners to spend significant amount of time in memorizing, which discourages learning at early stage. This article proposes a newly-developed color music notation system that may improve the recognition of the staff and the…

Economic and energetic analysis of capturing CO2 from ambient air

PubMed Central

House, Kurt Zenz; Baclig, Antonio C.; Ranjan, Manya; van Nierop, Ernst A.; Wilcox, Jennifer; Herzog, Howard J.

2011-01-01

Capturing carbon dioxide from the atmosphere (“air capture”) in an industrial process has been proposed as an option for stabilizing global CO2 concentrations. Published analyses suggest these air capture systems may cost a few hundred dollars per tonne of CO2, making it cost competitive with mainstream CO2 mitigation options like renewable energy, nuclear power, and carbon dioxide capture and storage from large CO2 emitting point sources. We investigate the thermodynamic efficiencies of commercial separation systems as well as trace gas removal systems to better understand and constrain the energy requirements and costs of these air capture systems. Our empirical analyses of operating commercial processes suggest that the energetic and financial costs of capturing CO2 from the air are likely to have been underestimated. Specifically, our analysis of existing gas separation systems suggests that, unless air capture significantly outperforms these systems, it is likely to require more than 400 kJ of work per mole of CO2, requiring it to be powered by CO2-neutral power sources in order to be CO2 negative. We estimate that total system costs of an air capture system will be on the order of $1,000 per tonne of CO2, based on experience with as-built large-scale trace gas removal systems. PMID:22143760

Incidence of adrenal insufficiency and impact of corticosteroid supplementation in critically ill children with systemic inflammatory syndrome and vasopressor-dependent shock.

PubMed

Hebbar, Kiran B; Stockwell, Jana A; Leong, Traci; Fortenberry, James D

2011-05-01

Adrenal insufficiency may be common in adults and children with vasopressor-resistant shock. We developed a protocolized approach to low-dose adrenocorticotropin testing and empirical low-dose glucocorticoid/mineralocorticoid supplementation in children with systemic inflammatory response syndrome and persistent hypotension following fluid resuscitation and vasopressor infusion. We hypothesized that absolute and relative adrenal insufficiency was common in children with systemic inflammatory response syndrome requiring vasopressor support and that steroid administration would be associated with decreased vasopressor need. Retrospective review of pediatric patients with systemic inflammatory response syndrome and vasopressor-dependent shock receiving protocol-based adrenocorticotropin testing and low-dose steroid supplementation. The incidence of absolute and relative adrenal insufficiency was determined using several definitions. Vasopressor dose requirements were evaluated before, and following, initiation of corticosteroids. Seventy-eight patients met inclusion criteria for systemic inflammatory response syndrome and shock; 40 had septic shock. Median age was 84 months (range, 0.5-295). By adrenocorticotropin testing, 44 (56%) had absolute adrenal insufficiency, 39 (50%) had relative adrenal insufficiency, and 69 (88%) had either form of adrenal insufficiency. Adrenal insufficiency incidence was significantly higher in children >2 yrs (p = .0209). Therapeutic interventions included median 80-mL/kg fluid resuscitation; 65% of patients required dopamine, 58% norepinephrine, and 49% dopamine plus norepinephrine. With steroid supplementation, median dopamine dose decreased from 10 to 4 μg/kg/min at 4 hrs (p = .0001), and median dose of norepinephrine decreased from 0.175 μg/kg/min to 0.05 μg/kg/min at 4 hrs (p = .039). Absolute and relative adrenal insufficiency was prevalent in this cohort of children with systemic inflammatory response syndrome and vasopressor-dependent shock and increased with age. Introduction of steroids produced a significant reduction in vasopressor duration and dosage. Use of low-dose adrenocorticotropin testing may help further delineate populations who require steroid supplementation.

Review of LLNL Mixed Waste Streams for the Application of Potential Waste Reduction Controls

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belue, A; Fischer, R P

2007-01-08

In July 2004, LLNL adopted the International Standard ISO 14001 as a Work Smart Standard in lieu of DOE Order 450.1. In support of this new requirement the Director issued a new environmental policy that was documented in Section 3.0 of Document 1.2, ''ES&H Policies of LLNL'', in the ES&H Manual. In recent years the Environmental Management System (EMS) process has become formalized as LLNL adopted ISO 14001 as part of the contract under which the laboratory is operated for the Department of Energy (DOE). On May 9, 2005, LLNL revised its Integrated Safety Management System Description to enhance existingmore » environmental requirements to meet ISO 14001. Effective October 1, 2005, each new project or activity is required to be evaluated from an environmental aspect, particularly if a potential exists for significant environmental impacts. Authorizing organizations are required to consider the management of all environmental aspects, the applicable regulatory requirements, and reasonable actions that can be taken to reduce negative environmental impacts. During 2006, LLNL has worked to implement the corrective actions addressing the deficiencies identified in the DOE/LSO audit. LLNL has begun to update the present EMS to meet the requirements of ISO 14001:2004. The EMS commits LLNL--and each employee--to responsible stewardship of all the environmental resources in our care. The generation of mixed radioactive waste was identified as a significant environmental aspect. Mixed waste for the purposes of this report is defined as waste materials containing both hazardous chemical and radioactive constituents. Significant environmental aspects require that an Environmental Management Plan (EMP) be developed. The objective of the EMP developed for mixed waste (EMP-005) is to evaluate options for reducing the amount of mixed waste generated. This document presents the findings of the evaluation of mixed waste generated at LLNL and a proposed plan for reduction.« less

A survey of the removable prosthodontic clinical experience of dental students.

PubMed

Herring, H W; Stephens, A P

1982-08-01

A survey was sent to every dental school in the contiguous United States and Puerto Rico to solicit answers to 15 questions concerning various aspects of the prosthodontic education of the dental student. It was found that student clinical experiences differed significantly among the regions in terms of the total number of prosthodontic patients treated per student. Fees also differed significantly among the regions. No comment was made on the possible effects of denturism on either the type of patient or the number of removable prosthodontic patients available for treatment by dental students. Concerning the difficulty in securing the various types of patients, all categories were mentioned as being somewhat in short supply, although the greatest shortage was complete denture patients. There was no universally recognized solution to the shortage of patients, although lowering of fees and substitution of requirements were mentioned most frequently. Pertaining to the presence or absence of a strict requirement system, the vast majority of schools reported use of at least some type of requirement system, though not necessarily a strict one.

Autonomous Assembly of Modular Structures in Space and on Extraterrestrial Locations

NASA Astrophysics Data System (ADS)

Alhorn, Dean C.

2005-02-01

The new U.S. National Vision for Space Exploration requires many new enabling technologies to accomplish the goals of space commercialization and returning humans to the moon and extraterrestrial environments. Traditionally, flight elements are complete sub-systems requiring humans to complete the integration and assembly. These bulky structures also require the use of heavy launch vehicles to send the units to a desired location. This philosophy necessitates a high degree of safety, numerous space walks at a significant cost. Future space mission costs must be reduced and safety increased to reasonably achieve exploration goals. One proposed concept is the autonomous assembly of space structures. This concept is an affordable, reliable solution to in-space and extraterrestrial assembly. Assembly is autonomously performed when two components join after determining that specifications are correct. Local sensors continue monitor joint integrity post assembly, which is critical for safety and structural reliability. Achieving this concept requires a change in space structure design philosophy and the development of innovative technologies to perform autonomous assembly. Assembly of large space structures will require significant numbers of integrity sensors. Thus simple, low-cost sensors are integral to the success of this concept. This paper addresses these issues and proposes a novel concept for assembling space structures autonomously. Core technologies required to achieve in space assembly are presented. These core technologies are critical to the goal of utilizing space in a cost efficient and safe manner. Additionally, these novel technologies can be applied to other systems both on earth and extraterrestrial environments.

SPS structures and control: A perspective

NASA Technical Reports Server (NTRS)

Ried, R. C.

1980-01-01

The characteristics and design requirements for the structure and control systems for a solar power satellite were evaluated. A simplistic, indicative analysis on a representative configuration was developed. Representative configuration masses and dimensions are given in convenient approximate magnitudes. The significance of structure control interaction and the significance of stiffness to the minimization of dynamic energy was demonstrated. It was found that the thermal environment for the SPS was dominated by solar radiation and waste heat rejection by the antenna. A more in-depth assessment of the control system design and associated system performance is still needed, specifically the inter-relatonships between control sensors, actuators, and structural response.

Utilizing Fission Technology to Enable Rapid and Affordable Access to any Point in the Solar System

NASA Technical Reports Server (NTRS)

Houts, Mike; Bonometti, Joe; Morton, Jeff; Hrbud, Ivana; Bitteker, Leo; VanDyke, Melissa; Godfroy, T.; Pedersen, K.; Dobson, C.; Patton, B.;

So much to do, so little time. To accomplish the mandatory initiatives of ARRA, healthcare organizations will require significant and thoughtful planning, prioritization and execution.

PubMed

Klein, Kimberly

2010-01-01

The American Recovery and Reinvestment Act of 2009 (ARRA) has set forth legislation for the healthcare community to achieve adoption of electronic health records (EHR), as well as form data standards, health information exchanges (HIE) and compliance with more stringent security and privacy controls under the HITECH Act. While the Office of the National Coordinator for Health Information Technology (ONCHIT) works on the definition of both "meaningful use" and "certification" of information technology systems, providers in particular must move forward with their IT initiatives to achieve the basic requirements for Medicare and Medicaid incentives starting in 2011, and avoid penalties that will reduce reimbursement beginning in 2015. In addition, providers, payors, government and non-government stakeholders will all have to balance the implementation of EHRs, working with HIEs, at the same time that they must upgrade their systems to be in compliance with ICD-10 and HIPAA 5010 code sets. Compliance deadlines for EHRs and HIEs begin in 2011, while ICD-10 diagnosis and procedure code sets compliance is required by October 2013 and HIPAA 5010 transaction sets, with one exception, is required by January 1, 2012. In order to accomplish these strategic and mandatory initiatives successfully and simultaneously, healthcare organizations will require significant and thoughtful planning, prioritization and execution.

Feasibility and demonstration of a cloud-based RIID analysis system

NASA Astrophysics Data System (ADS)

Wright, Michael C.; Hertz, Kristin L.; Johnson, William C.; Sword, Eric D.; Younkin, James R.; Sadler, Lorraine E.

2015-06-01

A significant limitation in the operational utility of handheld and backpack radioisotope identifiers (RIIDs) is the inability of their onboard algorithms to accurately and reliably identify the isotopic sources of the measured gamma-ray energy spectrum. A possible solution is to move the spectral analysis computations to an external device, the cloud, where significantly greater capabilities are available. The implementation and demonstration of a prototype cloud-based RIID analysis system have shown this type of system to be feasible with currently available communication and computational technology. A system study has shown that the potential user community could derive significant benefits from an appropriately implemented cloud-based analysis system and has identified the design and operational characteristics required by the users and stakeholders for such a system. A general description of the hardware and software necessary to implement reliable cloud-based analysis, the value of the cloud expressed by the user community, and the aspects of the cloud implemented in the demonstrations are discussed.

Information Requirements for Integrating Spatially Discrete, Feature-Based Earth Observations

NASA Astrophysics Data System (ADS)

Horsburgh, J. S.; Aufdenkampe, A. K.; Lehnert, K. A.; Mayorga, E.; Hsu, L.; Song, L.; Zaslavsky, I.; Valentine, D. L.

2014-12-01

Several cyberinfrastructures have emerged for sharing observational data collected at densely sampled and/or highly instrumented field sites. These include the CUAHSI Hydrologic Information System (HIS), the Critical Zone Observatory Integrated Data Management System (CZOData), the Integrated Earth Data Applications (IEDA) and EarthChem system, and the Integrated Ocean Observing System (IOOS). These systems rely on standard data encodings and, in some cases, standard semantics for classes of geoscience data. Their focus is on sharing data on the Internet via web services in domain specific encodings or markup languages. While they have made progress in making data available, it still takes investigators significant effort to discover and access datasets from multiple repositories because of inconsistencies in the way domain systems describe, encode, and share data. Yet, there are many scenarios that require efficient integration of these data types across different domains. For example, understanding a soil profile's geochemical response to extreme weather events requires integration of hydrologic and atmospheric time series with geochemical data from soil samples collected over various depth intervals from soil cores or pits at different positions on a landscape. Integrated access to and analysis of data for such studies are hindered because common characteristics of data, including time, location, provenance, methods, and units are described differently within different systems. Integration requires syntactic and semantic translations that can be manual, error-prone, and lossy. We report information requirements identified as part of our work to define an information model for a broad class of earth science data - i.e., spatially-discrete, feature-based earth observations resulting from in-situ sensors and environmental samples. We sought to answer the question: "What information must accompany observational data for them to be archivable and discoverable within a publication system as well as interpretable once retrieved from such a system for analysis and (re)use?" We also describe development of multiple functional schemas (i.e., physical implementations for data storage, transfer, and archival) for the information model that capture the requirements reported here.

QFD emphasis of IME design

NASA Astrophysics Data System (ADS)

Erickson, C. M.; Martinez, A.

1993-06-01

The 1992 Integrated Modular Engine (IME) design concept, proposed to the Air Force Space Systems Division as a candidate for a National Launch System (NLS) upper stage, emphasized a detailed Quality Functional Deployment (QFD) procedure which set the basis for its final selection. With a list of engine requirements defined and prioritized by the customer, a QFD procedure was implemented where the characteristics of a number of engine and component configurations were assessed for degree of requirement satisfaction. The QFD process emphasized operability, cost, reliability and performance, with relative importance specified by the customer. Existing technology and near-term advanced technology were surveyed to achieve the required design strategies. In the process, advanced nozzles, advanced turbomachinery, valves, controls, and operational procedures were evaluated. The integrated arrangement of three conventional bell nozzle thrust chambers with two advanced turbopump sets selected as the configuration meeting all requirements was rated significantly ahead of the other candidates, including the Aerospike and horizontal flow nozzle configurations.

A scope classification of data quality requirements for food composition data.

PubMed

Presser, Karl; Hinterberger, Hans; Weber, David; Norrie, Moira

2016-02-15

Data quality is an important issue when managing food composition data since the usage of the data can have a significant influence on policy making and further research. Although several frameworks for data quality have been proposed, general tools and measures are still lacking. As a first step in this direction, we investigated data quality requirements for an information system to manage food composition data, called FoodCASE. The objective of our investigation was to find out if different requirements have different impacts on the intrinsic data quality that must be regarded during data quality assessment and how these impacts can be described. We refer to the resulting classification with its categories as the scope classification of data quality requirements. As proof of feasibility, the scope classification has been implemented in the FoodCASE system. Copyright © 2015 Elsevier Ltd. All rights reserved.

Satellite Power Systems (SPS) concept definition study. Volume 5: Special emphasis studies. [rectenna and solar power satellite design studies

NASA Technical Reports Server (NTRS)

Hanley, G. M.

1980-01-01

Satellite configurations based on the Satellite Power System baseline requirements were analyzed and a preferred concept selected. A satellite construction base was defined, precursor operations incident to establishment of orbital support facilities identified, and the satellite construction sequence and procedures developed. Rectenna construction requirement were also addressed. Mass flow to orbit requirements were revised and traffic models established based on construction of 60 instead of 120 satellites. Analyses were conducted to determine satellite control, resources, manufacturing, and propellant requirements. The impact of the laser beam used for space-to-Earth power transmission upon the intervening atmosphere was examined as well as the inverse effect. The significant space environments and their effects on spacecraft components were investigated to define the design and operational limits imposed by the environments on an orbit transfer vehicle. The results show that LEO altitude 300 nmi and transfer orbit duration 6 months are preferrable.

Climate Observing Systems: Where are we and where do we need to be in the future

NASA Astrophysics Data System (ADS)

Baker, B.; Diamond, H. J.

2017-12-01

Climate research and monitoring requires an observational strategy that blends long-term, carefully calibrated measurements as well as short-term, focused process studies. The operation and implementation of operational climate observing networks and the provision of related climate services, both have a significant role to play in assisting the development of national climate adaptation policies and in facilitating national economic development. Climate observing systems will require a strong research element for a long time to come. This requires improved observations of the state variables and the ability to set them in a coherent physical (as well as a chemical and biological) framework with models. Climate research and monitoring requires an integrated strategy of land/ocean/atmosphere observations, including both in situ and remote sensing platforms, and modeling and analysis. It is clear that we still need more research and analysis on climate processes, sampling strategies, and processing algorithms.

Message handling system concepts and services in a land mobile satellite system

NASA Technical Reports Server (NTRS)

Barberis, S.; Settimo, F.; Giralda, A.; Mistretta, I.; Loisy, C.; Parmentier, J. L.

1990-01-01

A network architecture containing the capabilities offered by the Message Handling System (MHS) to the PRODAT Land Mobile Satellite System (LMSS) is described taking into account the constraints of a preexisting satellite system which is going to become operational. The mapping between MHS services and PRODAT requirements is also reported and shows that the supplied performance can be significantly enhanced to both fixed and mobile users. The impact of the insertion of additional features on the system structure, especially on the centralized control unit, are also addressed.

Assessing healthcare market trends and capital needs: 1996-2000.

PubMed

Coile, R C

1995-08-01

An analysis of recent data suggests several significant trends for the next five years, including a continuation of market-based reform, increases in managed care penetration, growth of Medicare and Medicaid health maintenance organizations, and erosion of hospital profits. A common response to these trends is to create integrated delivery systems, which can require significant capital investment. The wisest capital investment strategy may be to avoid asset-based integration in favor of "virtual integration," which emphasizes coordination through patient-management agreements, provider incentives, and information systems, rather than investment in large number of facilities.

NASA Langley Research Center Systems Analysis & Concepts Directorate Participation in the Exploration Systems Architecture Study

NASA Technical Reports Server (NTRS)

Keyes, Jennifer; Troutman, Patrick A.; Saucillo, Rudolph; Cirillo, William M.; Cavanaugh, Steve; Stromgren, Chel

2006-01-01

The NASA Langley Research Center (LaRC) Systems Analysis & Concepts Directorate (SACD) began studying human exploration missions beyond low Earth orbit (LEO) in the year 1999. This included participation in NASA s Decadal Planning Team (DPT), the NASA Exploration Team (NExT), Space Architect studies and Revolutionary Aerospace Systems Concepts (RASC) architecture studies that were used in formulating the new Vision for Space Exploration. In May of 2005, NASA initiated the Exploration Systems Architecture Study (ESAS). The primary outputs of the ESAS activity were concepts and functional requirements for the Crewed Exploration Vehicle (CEV), its supporting launch vehicle infrastructure and identification of supporting technology requirements and investments. An exploration systems analysis capability has evolved to support these functions in the past and continues to evolve to support anticipated future needs. SACD had significant roles in supporting the ESAS study team. SACD personnel performed the liaison function between the ESAS team and the Shuttle/Station Configuration Options Team (S/SCOT), an agency-wide team charged with using the Space Shuttle to complete the International Space Station (ISS) by the end of Fiscal Year (FY) 2010. The most significant of the identified issues involved the ability of the Space Shuttle system to achieve the desired number of flights in the proposed time frame. SACD with support from the Kennedy Space Center performed analysis showing that, without significant investments in improving the shuttle processing flow, that there was almost no possibility of completing the 28-flight sequence by the end of 2010. SACD performed numerous Lunar Surface Access Module (LSAM) trades to define top level element requirements and establish architecture propellant needs. Configuration trades were conducted to determine the impact of varying degrees of segmentation of the living capabilities of the combined descent stage, ascent stage, and other elements. The technology assessment process was developed and implemented by SACD as the ESAS architecture was refined. SACD implemented a rigorous and objective process which included (a) establishing architectural functional needs, (b) collection, synthesis and mapping of technology data, and (c) performing an objective decision analysis resulting in technology development investment recommendations. The investment recommendation provided budget, schedule, and center/program allocations to develop required technologies for the exploration architecture, as well as the identification of other investment opportunities to maximize performance and flexibility while minimizing cost and risk. A summary of the trades performed and methods utilized by SACD for the Exploration Systems Mission Directorate (ESAS) activity is presented along with how SACD is currently supporting the implementation of the Vision for Space Exploration.

Evaluation of apically extruded debris during root canal retreatment with several NiTi systems.

PubMed

Dincer, A N; Er, O; Canakci, B C

2015-12-01

To compare the amount of debris extruded apically during root canal retreatment using ProTaper, Mtwo and Reciproc instruments with hand H-files. In total, 60 freshly extracted human mandibular incisor teeth were used. All root canals were prepared with a Reciproc R25 file than filled with Gutta-percha and AH Plus sealer using cold lateral condensation before being assigned randomly to four groups (n = 15 each). In group 1, root fillings were removed with the Protaper Universal retreatment system; ProTaper Universal F3 and F4 instruments were used for the final preparation. In group 2, root fillings were removed with the Mtwo retreatment system; Mtwo size 30, .06 taper, size 35, .06 taper and size 40, .06 taper files were used for the final preparation. In group 3, root fillings were removed with Reciproc R25 instruments; Reciproc R40 instruments were used for the final preparation. In group 4, the root fillings were removed with Gates Glidden burs and sizes 35, 30 and 25 H-files; for final preparation, a size 40 H-file was used. Glass vials were used for debris collection. The vials were weighed before and after Gutta-percha removal. Additionally, the times required for the retreatment procedures were recorded. Data were analysed statistically using one-way analysis of variance. The Reciproc system produced significantly smaller amounts of apical extruded debris than the other groups (P < 0.05). There was no significant difference between the Mtwo, H-file and ProTaper groups. The ProTaper and Reciproc groups required significantly less time than the Mtwo and H-file groups (P < 0.001). Use of the reciprocating single file system resulted in the extrusion of significantly less debris compared with the full-sequence rotary NiTi instruments and hand filing. Use of the ProTaper and Reciproc instruments required less time for retreatment procedures than use of the Mtwo or H-file. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Optimisation of a propagation-based x-ray phase-contrast micro-CT system

NASA Astrophysics Data System (ADS)

Nesterets, Yakov I.; Gureyev, Timur E.; Dimmock, Matthew R.

2018-03-01

Micro-CT scanners find applications in many areas ranging from biomedical research to material sciences. In order to provide spatial resolution on a micron scale, these scanners are usually equipped with micro-focus, low-power x-ray sources and hence require long scanning times to produce high resolution 3D images of the object with acceptable contrast-to-noise. Propagation-based phase-contrast tomography (PB-PCT) has the potential to significantly improve the contrast-to-noise ratio (CNR) or, alternatively, reduce the image acquisition time while preserving the CNR and the spatial resolution. We propose a general approach for the optimisation of the PB-PCT imaging system. When applied to an imaging system with fixed parameters of the source and detector this approach requires optimisation of only two independent geometrical parameters of the imaging system, i.e. the source-to-object distance R 1 and geometrical magnification M, in order to produce the best spatial resolution and CNR. If, in addition to R 1 and M, the system parameter space also includes the source size and the anode potential this approach allows one to find a unique configuration of the imaging system that produces the required spatial resolution and the best CNR.

NGAP: Compliance as a Service

NASA Astrophysics Data System (ADS)

McLaughlin, B. D.; Pawloski, A. W.

2015-12-01

Modern development practices require the ability to quickly and easily host an application. Small projects cannot afford to maintain a large staff for infrastructure maintenance. Rapid prototyping fosters innovation. However, maintaining the integrity of data and systems demands care, particularly in a government context. The extensive data holdings that make up much of the value of NASA's EOSDIS (Earth Observing System Data and Information System) are stored in a number of locations, across a wide variety of applications, ranging from small prototypes to large computationally-intensive operational processes.However, it is increasingly difficult for an application to implement the required security controls, perform required registrations and inventory entries, ensure logging, monitoring, patching, and then ensure that all these activities continue for the life of that application, let alone five, or ten, or fifty applications. This process often takes weeks or months to complete and requires expertise in a variety of different domains such as security, systems administration, development, etc.NGAP, the Next Generation Application Platform, is tackling this problem by investigating, automating, and resolving many of the repeatable policy hurdles that a typical application must overcome. This platform provides a relatively simple and straightforward process by which applications can commit source code to a repository and then deploy that source code to a cloud-based infrastructure, all while meeting NASA's policies for security, governance, inventory, reliability, and availability. While there is still work for the application owner for any application hosting, NGAP handles a significant portion of that work.This talk will discuss areas where we have made significant progress, areas that are complex or must remain human-intensive, and areas where we are still striving to improve this application deployment and hosting pipeline.

Improving water resources management efficiency for cranberry production

NASA Astrophysics Data System (ADS)

Rousseau, A. N.; Bigah, Y.; Gumiere, S.

2016-12-01

Water needs vary significantly from one plant to another and unlike many other plants cranberry is a very sensitive to weather conditions. This inherent sensitivity requires irrigation for protection against frost and excessive heat when the air temperature falls below 0o C and rises above 25o C, respectively. In addition, cranberry fields require significant amount of water as fields require about 406 mm of water to ease the harvesting process. Lastly, fields need icing for protection during winter months and that requires maintaining almost 203 mm of water above cranberry plants for at least three consecutive days. The intensive use of water for cranberry production has triggered several water management projects, particularly in Canada, the second largest producer in the world. The outcomes of these projects have improved water management to a point where nowadays most cranberry farms recycle water in a closed circuit during the production cycle, especially during the harvesting and icing phases. However, up till now very little effort had been put into assessing the efficiency of the recycling system such that a question remained: how much does a closed circuit system contribute to reducing the annual water use? The objective of this project is to assess water use for cranberry production and associated management efficiency of two different recycling systems located within watersheds under slightly different climatic conditions. The methodological approach is based on the development of a mathematical model capable of simulating water needs for a wide range of climatic conditions and over an extended period of time (e.g., 30 years). The outcome of this project has potential to further improve our understanding of the inter-annual dynamics of water needs and supply and ultimately improved recycling systems.

Comparative study of two precision overdenture attachment designs.

PubMed

Cohen, B I; Pagnillo, M; Condos, S; Deutsch, A S

1996-08-01

In this study two precision overdenture attachment designs were tested for retention--a nylon overdenture cap system and a new cap and keeper system. The new cap and keeper system was designed to reduce the time involved in replacing a cap worn by the conditions of the oral environment. Six groups were tested at two different angles and retentive failure was examined at two different angles (26 and 0 degrees). Failure was measured in pounds with a force gauge over a 2000 pull cycle. The amount of force required to remove caps for two overdenture caps and a replaced cap for the metal keeper system was determined. Two dependent variables were absolute force and relative force. Repeated measures analysis of variance (RMANOVA) was used to compare the between-subjects effects of cap and angle, and the within-subjects effect of pull. The results indicated a significant difference between cap types (p < 0.0001) with respect to the relative force required to remove the cap. There was no effect of angle. For absolute force, RMANOVA revealed a highly significant interaction between pull and cap (p < 0.0001). Thus, the way that force changed over pulls depended on which cap was used (no effect of angle). For relative force, RMANOVA revealed no interaction between pull and cap, but there was a main effect of cap type (p < 0.0001) (no effect of angle). The nylon cap design required less force for removal but showed more consistency in the force required over the course of the 2000 pulls when compared with the keeper with cap insert. The results obtained in this study were consistent with similar studies in literature.

47 CFR 76.54 - Significantly viewed signals; method to be followed for special showings.

Code of Federal Regulations, 2010 CFR

2010-10-01

... located, in whole or in part, and on all other system community units, franchisees, and franchise.... 339(d). (j) Notwithstanding the requirements of this section, the signal of a television broadcast...

Good Asset Accounting Procedures for Schools.

ERIC Educational Resources Information Center

Golz, William C.

1981-01-01

Increased accountability is required in school accounting due to rising education costs and the significant investment made in property and equipment in educational facilities. Guidelines for planning and implementing a property record-keeping system are provided. (Author/MLF)

Structures and materials technology issues for reusable launch vehicles

NASA Technical Reports Server (NTRS)

Dixon, S. C.; Tenney, D. R.; Rummler, D. R.; Wieting, A. R.; Bader, R. M.

1985-01-01

Projected space missions for both civil and defense needs require significant improvements in structures and materials technology for reusable launch vehicles: reductions in structural weight compared to the Space Shuttle Orbiter of up to 25% or more, a possible factor of 5 or more increase in mission life, increases in maximum use temperature of the external surface, reusable containment of cryogenic hydrogen and oxygen, significant reductions in operational costs, and possibly less lead time between technology readiness and initial operational capability. In addition, there is increasing interest in hypersonic airbreathing propulsion for launch and transmospheric vehicles, and such systems require regeneratively cooled structure. The technology issues are addressed, giving brief assessments of the state-of-the-art and proposed activities to meet the technology requirements in a timely manner.

Efficient computational nonlinear dynamic analysis using modal modification response technique

NASA Astrophysics Data System (ADS)

Marinone, Timothy; Avitabile, Peter; Foley, Jason; Wolfson, Janet

2012-08-01

Generally, structural systems contain nonlinear characteristics in many cases. These nonlinear systems require significant computational resources for solution of the equations of motion. Much of the model, however, is linear where the nonlinearity results from discrete local elements connecting different components together. Using a component mode synthesis approach, a nonlinear model can be developed by interconnecting these linear components with highly nonlinear connection elements. The approach presented in this paper, the Modal Modification Response Technique (MMRT), is a very efficient technique that has been created to address this specific class of nonlinear problem. By utilizing a Structural Dynamics Modification (SDM) approach in conjunction with mode superposition, a significantly smaller set of matrices are required for use in the direct integration of the equations of motion. The approach will be compared to traditional analytical approaches to make evident the usefulness of the technique for a variety of test cases.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kristine Barrett; Shannon Bragg-Sitton

The Advanced Light Water Reactor (LWR) Nuclear Fuel Development Research and Development (R&D) Pathway encompasses strategic research focused on improving reactor core economics and safety margins through the development of an advanced fuel cladding system. To achieve significant operating improvements while remaining within safety boundaries, significant steps beyond incremental improvements in the current generation of nuclear fuel are required. Fundamental improvements are required in the areas of nuclear fuel composition, cladding integrity, and the fuel/cladding interaction to allow power uprates and increased fuel burn-up allowance while potentially improving safety margin through the adoption of an “accident tolerant” fuel system thatmore » would offer improved coping time under accident scenarios. With a development time of about 20 – 25 years, advanced fuel designs must be started today and proven in current reactors if future reactor designs are to be able to use them with confidence.« less

Computerized physician order entry from a chief information officer perspective.

PubMed

Cotter, Carole M

2004-12-01

Designing and implementing a computerized physician order entry system in the critical care units of a large urban hospital system is an enormous undertaking. With their significant potential to improve health care and significantly reduce errors, the time for computerized physician order entry or physician order management systems is past due. Careful integrated planning is the key to success, requiring multidisciplinary teams at all levels of clinical and administrative management to work together. Articulated from the viewpoint of the Chief Information Officer of Lifespan, a not-for-profit hospital system in Rhode Island, the vision and strategy preceding the information technology plan, understanding the system's current state, the gap analysis between current and future state, and finally, building and implementing the information technology plan are described.

Cost effective propulsion systems for small satellites using butane propellant

NASA Astrophysics Data System (ADS)

Gibbon, D.; Underwood, C.; Sweeting, M.; Amri, R.

2002-07-01

This paper will describe the work performed at the Surrey Space Centre to produce cost effective propulsion systems for small spacecraft with relatively low deltaV (ΔV) requirements. Traditionally, cold gas nitrogen systems have been used for this type of application, however they have high storage volume requirements. This can be a problem on small spacecraft, which are typically volume limited. An alternative solution is to use liquefied gases, which store as liquids, hence have reasonable density levels, and can be used in a cold gas thruster. At the Surrey Space Centre, butane has been selected as the propellant of choice. Although it has slightly lower specific impulse performance than nitrogen, it has a significantly higher storage density and it stores at a very low pressure, hence no regulation system is required. On 28 th June 2000 Surrey Satellite Technology Ltd (SSTL) launched it first nanosatellite SNAP-1. This 6.5kg spacecraft was equipped with a small cold gas propulsion system utilising 32.6 grams of butane propellant. During the propulsion system operation phase the spacecraft's semi major axis was raised by nearly 4 kilometers using the propulsion system. The design of the propulsion system will be described and the low cost features highlighted. Telemetry data will be used to describe the propulsion operations and an overall mission specific impulse will be derived. SSTL are currently under contract to build three Earth observation spacecraft for a Disaster Monitoring Constellation (DMC). Each spacecraft will weigh approx 100 kg and have a ΔV requirement of 10 m/sec. A butane system has been designed and manufactured to meet the requirements of these spacecraft. The system is based very much on the flight heritage of the SNAP-1 system, with the addition of greater propellant storage capacity. The lessons learnt from the SNAP-1 operation will be reviewed and the resulting design improvements on the DMC propulsion systems will be detailed.

Two Wavelength Ti:sapphire Laser for Ozone DIAL Measurements from Aircraft

NASA Technical Reports Server (NTRS)

Situ, Wen; DeYoung, Russel J.

1998-01-01

Laser remote sensing of ozone from aircraft has proven to be a valuable technique for understanding the distribution and dynamics of ozone in the atmosphere. Presently the differential absorption lidar (DIAL) technique, using dual ND:YAG lasers that are doubled to pump dye lasers which in turn are doubled into the UV for the "on" and "off' line lasers, is used on either the NASA DC-8 or P-3 aircraft. Typically, the laser output for each line is 40-mJ and this is split into two beams, one looking up and the other downward, each beam having about 20-mJ. The residual ND:YAG (1.06 micron) and dye laser energies are also transmitted to obtain information on the atmospheric aerosols. While this system has operated well, there are several system characteristics that make the system less than ideal for aircraft operations. The system, which uses separate "on" and "off" line lasers, is quite large and massive requiring valuable aircraft volume and weight. The dye slowly degrades with time requiring replacement. The laser complexity requires a number of technical people to maintain the system performance. There is also the future interest in deploying an ozone DIAL system in an Unpiloted Atmospheric Vehicle (UAV) which would require a total payload mass of less than 150 kg and power requirement of less than 1500 W. A laser technology has emerged that could potentially provide significant enhancements over the present ozone DIAL system. The flashlamp pumped Ti:sapphire laser system is an emerging technology that could reduce the mass and volume over the present system and also provide a system with fewer conversion steps, reducing system complexity. This paper will discuss preliminary results from a flashlamp-pumped Ti:sapphire laser constructed as a radiation source for a UV DIAL system to measure ozone.

Determining Training Device Requirements in Army Aviation Systems

NASA Technical Reports Server (NTRS)

Poumade, M. L.

1984-01-01

A decision making methodology which applies the systems approach to the training problem is discussed. Training is viewed as a total system instead of a collection of individual devices and unrelated techniques. The core of the methodology is the use of optimization techniques such as the transportation algorithm and multiobjective goal programming with training task and training device specific data. The role of computers, especially automated data bases and computer simulation models, in the development of training programs is also discussed. The approach can provide significant training enhancement and cost savings over the more traditional, intuitive form of training development and device requirements process. While given from an aviation perspective, the methodology is equally applicable to other training development efforts.

Solar thermal plant impact analysis and requirements definition

NASA Technical Reports Server (NTRS)

Gupta, Y. P.

1980-01-01

Progress on a continuing study comprising of ten tasks directed at defining impact and requirements for solar thermal power systems (SPS), 1 to 10 MWe each in capacity, installed during 1985 through year 2000 in a utility or a nonutility load in the United States is summarized. The point focus distributed receiver (PFDR) solar power systems are emphasized. Tasks 1 through 4, completed to date, include the development of a comprehensive data base on SPS configurations, their performance, cost, availability, and potential applications; user loads, regional characteristics, and an analytic methodology that incorporates the generally accepted utility financial planning methods and several unique modifications to treat the significant and specific characteristics of solar power systems deployed in either central or distributed power generation modes, are discussed.

eHealth integration and interoperability issues: towards a solution through enterprise architecture.

PubMed

Adenuga, Olugbenga A; Kekwaletswe, Ray M; Coleman, Alfred

2015-01-01

Investments in healthcare information and communication technology (ICT) and health information systems (HIS) continue to increase. This is creating immense pressure on healthcare ICT and HIS to deliver and show significance in such investments in technology. It is discovered in this study that integration and interoperability contribute largely to this failure in ICT and HIS investment in healthcare, thus resulting in the need towards healthcare architecture for eHealth. This study proposes an eHealth architectural model that accommodates requirement based on healthcare need, system, implementer, and hardware requirements. The model is adaptable and examines the developer's and user's views that systems hold high hopes for their potential to change traditional organizational design, intelligence, and decision-making.

Feasibility of high recovery highwall mining equipment. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-01-01

Three equipment systems exhibited significant promise: the RSV Miner, a surface longwall using standard underground equipment, and the variable angle auger. Other equipment systems showing considerable merit were the surface shortwall, and the two extended depth augers. Of the three most significant systems, the RSV Miner exhibits the greatest versatility and adaptability. It may be used competently in many surface mining applications and readily adapts to geologic anomalies and changing seam heights. The machine employs steering and guidance equipment and provides the necessary capabilities for extended depth operation. Safety is good, as no men are required to work underground. However,more » most important is the system's recovery factor of approximately 75% to 80% of the in-situ coal reserve within reach. The surface longwall system using standard underground equipment (preferably a ranging drum shearer in conjunction with shield supports) is most suited to either a trench mining or a modified area mining application. Both applications would allow the length of the face to be held constant. Another important consideration is legal requirements for a tailgate entry, which would necessitate additional equipment for development in a modified area mining application. When compared to surface shortwall, surface longwall exhibits higher productivity, a far greater equipment selection which allows system tailoring to geologic conditions, and greater roof control due to the significantly smaller section of overburden that must be supported. Recovery should approach, and possibly exceed, 90% of the coal in-place. The variable angle auger, which is currently only a concept, fills a very real need for which no other equipment is available at this time.« less

Energy Storage Requirements for Achieving 50% Penetration of Solar Photovoltaic Energy in California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denholm, Paul; Margolis, Robert

2016-09-01

We estimate the storage required to enable PV penetration up to 50% in California (with renewable penetration over 66%), and we quantify the complex relationships among storage, PV penetration, grid flexibility, and PV costs due to increased curtailment. We find that the storage needed depends strongly on the amount of other flexibility resources deployed. With very low-cost PV (three cents per kilowatt-hour) and a highly flexible electric power system, about 19 gigawatts of energy storage could enable 50% PV penetration with a marginal net PV levelized cost of energy (LCOE) comparable to the variable costs of future combined-cycle gas generatorsmore » under carbon constraints. This system requires extensive use of flexible generation, transmission, demand response, and electrifying one quarter of the vehicle fleet in California with largely optimized charging. A less flexible system, or more expensive PV would require significantly greater amounts of storage. The amount of storage needed to support very large amounts of PV might fit within a least-cost framework driven by declining storage costs and reduced storage-duration needs due to high PV penetration.« less

Energy Storage Requirements for Achieving 50% Solar Photovoltaic Energy Penetration in California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denholm, Paul; Margolis, Robert

2016-08-01

We estimate the storage required to enable PV penetration up to 50% in California (with renewable penetration over 66%), and we quantify the complex relationships among storage, PV penetration, grid flexibility, and PV costs due to increased curtailment. We find that the storage needed depends strongly on the amount of other flexibility resources deployed. With very low-cost PV (three cents per kilowatt-hour) and a highly flexible electric power system, about 19 gigawatts of energy storage could enable 50% PV penetration with a marginal net PV levelized cost of energy (LCOE) comparable to the variable costs of future combined-cycle gas generatorsmore » under carbon constraints. This system requires extensive use of flexible generation, transmission, demand response, and electrifying one quarter of the vehicle fleet in California with largely optimized charging. A less flexible system, or more expensive PV would require significantly greater amounts of storage. The amount of storage needed to support very large amounts of PV might fit within a least-cost framework driven by declining storage costs and reduced storage-duration needs due to high PV penetration.« less

Improvement of cement plant dust emission by bag filter system

NASA Astrophysics Data System (ADS)

Wahyu Purnomo, Chandra; Budhijanto, Wiratni; Alfisyah, Muziibu; Triyono

2018-03-01

The limestone quarry in PT Indocement Tunggal Prakarsa (ITP) in Cirebon is considered as a complex quarry in terms of chemical composition and material hardness. From the beginning of the plant operation up to the end of 2015, the dust removal was rely on electrostatic precipitator (EP) system. Whenever limestone from specific quarry zones were incorporated into Raw Mill (RM) feed or there was an upset condition, the dust emission increased significantly. Beside higher demand of electricity, an EP system requires lower gas inlet temperature in order to remove the dust effectively which requires larger cooling water in the previous gas conditioning tower to cool down gas from 400 °C to about 100 °C. By considering the drawbacks, the EP system was replaced by a bag filter (BF) system. The BF allows higher temperature of gas inlet and it has higher dust removal efficiency. In this study, the efficiency of the two different dust removal systems is compared. The effect of process variables i.e. RM feed, kiln feed, inlet temperature and pressure, and small size particle fraction to the dust emission are studied by multivariate linier regression analysis. It is observed that the BF system can reduce significantly the dust emission from 30 to 6 mg/m3 and in the same time reducing CO2 emission by 0.24 ton/year from the electricity consumption saving.

Climate impact of beef: an analysis considering multiple time scales and production methods without use of global warming potentials

NASA Astrophysics Data System (ADS)

Pierrehumbert, R. T.; Eshel, G.

2015-08-01

An analysis of the climate impact of various forms of beef production is carried out, with a particular eye to the comparison between systems relying primarily on grasses grown in pasture (‘grass-fed’ or ‘pastured’ beef) and systems involving substantial use of manufactured feed requiring significant external inputs in the form of synthetic fertilizer and mechanized agriculture (‘feedlot’ beef). The climate impact is evaluated without employing metrics such as {{CO}}2{{e}} or global warming potentials. The analysis evaluates the impact at all time scales out to 1000 years. It is concluded that certain forms of pastured beef production have substantially lower climate impact than feedlot systems. However, pastured systems that require significant synthetic fertilization, inputs from supplemental feed, or deforestation to create pasture, have substantially greater climate impact at all time scales than the feedlot and dairy-associated systems analyzed. Even the best pastured system analyzed has enough climate impact to justify efforts to limit future growth of beef production, which in any event would be necessary if climate and other ecological concerns were met by a transition to primarily pasture-based systems. Alternate mitigation options are discussed, but barring unforseen technological breakthroughs worldwide consumption at current North American per capita rates appears incompatible with a 2 °C warming target.

Shared Learning and the Drive to Improve Patient Safety: Lessons Learned from the Pittsburgh Regional Healthcare Initiative

DTIC Science & Technology

2005-01-01

the environmental, cultural, and infrastructure changes in health care that will be necessary to achieve significant, widespread patient safety...to improved patient outcomes. Achievement of improved patient safety requires enhanced health care leadership commitment and learning systems that... health care organizations and practitioners to work together to identify and solve patient safety problems. Providing safe care requires a learning

Human exploration mission studies

NASA Technical Reports Server (NTRS)

Cataldo, Robert L.

1990-01-01

This paper describes several case studies of human space exploration, considered by the NASA's Office of Exploration in 1988. Special attention is given to the mission scenarios, the critical technology required in these expeditions, and the extraterrestrial power requirements of significant system elements. The cases examined include a manned expedition to Phobos, the inner Martian moon; a human expedition to Mars; the Lunar Observatory; and a lunar outpost to early Mars evolution.

Technology requirements for future Earth-to-geosynchronous orbit transportation systems. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Caluori, V. A.; Conrad, R. T.; Jenkins, J. C.

1980-01-01

Technologies including accelerated technology that are critical to performance and/or provide cost advantages for future space transportation systems are identified. Mission models are scoped and include priority missions, and cargo missions. Summary data, providing primary design concepts and features, are given for the SSTO, HLLV, POTV, and LCOTV vehicles. Significant system costs and total system costs in terms of life cycle costs in both discounted and undiscounted dollars are summarized for each of the vehicles.

Portable brine evaporator unit, process, and system

DOEpatents

Hart, Paul John; Miller, Bruce G.; Wincek, Ronald T.; Decker, Glenn E.; Johnson, David K.

2009-04-07

The present invention discloses a comprehensive, efficient, and cost effective portable evaporator unit, method, and system for the treatment of brine. The evaporator unit, method, and system require a pretreatment process that removes heavy metals, crude oil, and other contaminates in preparation for the evaporator unit. The pretreatment and the evaporator unit, method, and system process metals and brine at the site where they are generated (the well site). Thus, saving significant money to producers who can avoid present and future increases in transportation costs.

Application of Advanced Multi-Core Processor Technologies to Oceanographic Research

DTIC Science & Technology

2014-09-30

Jordan Stanway are taking on the work of analyzing their code, and we are working on the Robot Operating System (ROS) and MOOS-DB systems to evaluate...Linux/GNU operating system that should reduce the time required to build the kernel and userspace significantly. This part of the work is vital to...the platform to be used not only as a service, but also as a private deployable package. As much as possible, this system was built using operating

Non-Cooled Power System for Venus Lander

NASA Technical Reports Server (NTRS)

Salazar, Denise; Landis, Geoffrey A.; Colozza, Anthony J.

2014-01-01

The Planetary Science Decadal Survey of 2013-2022 stated that the exploration of Venus is of significant interest. Studying the seismic activity of the planet is of particular importance because the findings can be compared to the seismic activity of Earth. Further, the geological and atmospheric properties of Venus will shed light into the past and future of Earth. This paper presents a radioisotope power system (RPS) design for a small low-power Venus lander. The feasibility of the new power system is then compared to that of primary batteries. A requirement for the power source system is to avoid moving parts in order to not interfere with the primary objective of the mission - to collect data about the seismic activity of Venus using a seismometer. The target mission duration of the lander is 117 days, a significant leap from Venera 13, the longest-lived lander on the surface of Venus, which survived for 2 hours. One major assumption for this mission design is that the power source system will not provide cooling to the other components of the lander. This assumption is based on high-temperature electronics technology that will enable the electronics and components of the lander to operate at Venus surface temperature. For the proposed RPS, a customized General Purpose Heat Source Radioisotope Thermoelectric Generator (GPHSRTG) is designed and analyzed. The GPHS-RTG is chosen primarily because it has no moving parts and it is capable of operating for long duration missions on the order of years. This power system is modeled as a spherical structure for a fundamental thermal analysis. The total mass and electrical output of the system are calculated to be 24 kilograms and 26 Watts, respectively. An alternative design for a battery-based power system uses Sodium Sulfur batteries. To deliver a similar electrical output for 117 days, the battery mass is calculated to be 234 kilograms. Reducing mission duration or power required will reduce the required battery mass. Finally, the advantages and disadvantages of both power systems with regard to science return, risk, and cost are briefly compared. The design of the radioisotope power system is considerably riskier because it is novel and would require additional years of further refinement, manufacturing, safety analysis, and testing that the primary batteries do not need. However, the lifetime of the radioisotope power system makes its science return more promising.

Energy Conversion Alternatives Study (ECAS), General Electric Phase 1. Volume 1: Executive summary. [using coal or coal derived fuels

NASA Technical Reports Server (NTRS)

Corman, J. C.

1976-01-01

A data base for the comparison of advanced energy conversion systems for utility applications using coal or coal-derived fuels was developed. Estimates of power plant performance (efficiency), capital cost, cost of electricity, natural resource requirements, and environmental intrusion characteristics were made for ten advanced conversion systems. Emphasis was on the energy conversion system in the context of a base loaded utility power plant. All power plant concepts were premised on meeting emission standard requirements. A steam power plant (3500 psig, 1000 F) with a conventional coal-burning furnace-boiler was analyzed as a basis for comparison. Combined cycle gas/steam turbine system results indicated competitive efficiency and a lower cost of electricity compared to the reference steam plant. The Open-Cycle MHD system results indicated the potential for significantly higher efficiency than the reference steam plant but with a higher cost of electricity.

A Microelectromechanical High-Density Energy Storage/Rapid Release System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodgers, M. Steven; Allen, Jim J.; Meeks, Kent D.

1999-07-21

One highly desirable characteristic of electrostatically driven microelectromechanical systems (MEMS) is that they consume very little power. The corresponding drawback is that the force they produce may be inadequate for many applications. It has previously been demonstrated that gear reduction units or microtransmissions can substantially increase the torque generated by microengines. Operating speed, however, is also reduced by the transmission gear ratio. Some applications require both high speed and high force. If this output is only required for a limited period of time, then energy could be stored in a mechanical system and rapidly released upon demand. We have designed,more » fabricated, and demonstrated a high-density energy storage/rapid release system that accomplishes this task. Built using a 5-level surface micromachining technology, the assembly closely resembles a medieval crossbow. Energy releases on the order of tens of nanojoules have already been demonstrated, and significantly higher energy systems are under development.« less

Advanced Launch System (ALS) actuation and power systems impact operability and cost

NASA Technical Reports Server (NTRS)

Sundberg, Gale R.

1990-01-01

To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrical power system and controls for all actuation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a specific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military and civilian aircraft, lunar/Martian vehicles, and a multitude of commercial applications.

Advanced Launch System (ALS): Electrical actuation and power systems improve operability and cost picture

NASA Technical Reports Server (NTRS)

Sundberg, Gale R.

1990-01-01

To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrical power system and controls for all actuation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a specific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military and civilian aircraft, lunar/Martian vehicles, and a multitude of commercial applications.

Advanced launch system (ALS) - Electrical actuation and power systems improve operability and cost picture

NASA Technical Reports Server (NTRS)

Sundberg, Gale R.

1990-01-01

To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrrical power system and controls for all aviation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a sdpecific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military ans civilian aircraft, lunar/Martian vehicles, and a multitude of comercial applications.

Turbulence flight director analysis and preliminary simulation

NASA Technical Reports Server (NTRS)

Johnson, D. E.; Klein, R. E.

1974-01-01

A control column and trottle flight director display system is synthesized for use during flight through severe turbulence. The column system is designed to minimize airspeed excursions without overdriving attitude. The throttle system is designed to augment the airspeed regulation and provide an indication of the trim thrust required for any desired flight path angle. Together they form an energy management system to provide harmonious display indications of current aircraft motions and required corrective action, minimize gust upset tendencies, minimize unsafe aircraft excursions, and maintain satisfactory ride qualities. A preliminary fixed-base piloted simulation verified the analysis and provided a shakedown for a more sophisticated moving-base simulation to be accomplished next. This preliminary simulation utilized a flight scenario concept combining piloting tasks, random turbulence, and discrete gusts to create a high but realistic pilot workload conducive to pilot error and potential upset. The turbulence director (energy management) system significantly reduced pilot workload and minimized unsafe aircraft excursions.

Microelectromechanical high-density energy storage/rapid release system

NASA Astrophysics Data System (ADS)

Rodgers, M. Steven; Allen, James J.; Meeks, Kent D.; Jensen, Brian D.; Miller, Samuel L.

1999-08-01

One highly desirable characteristic of electrostatically driven microelectromechanical systems (MEMS) is that they consume very little power. The corresponding drawback is that the force they produce may be inadequate for many applications. It has previously been demonstrated that gear reduction units or microtransmissions can substantially increase the torque generated by microengines. Operating speed, however, is also reduced by the transmission gear ratio. Some applications require both high speed and high force. If this output is only required for a limited period of time, then energy could be stored in a mechanical system and rapidly released upon demand. We have designed, fabricated, and demonstrated a high-density energy storage/rapid release system that accomplishes this task. Built using a 5-level surface micromachining technology, the assembly closely resembles a medieval crossbow. Energy releases on the order of tens of nanojoules have already been demonstrated, and significantly higher energy systems are under development.

[Infantile haemangioma: clinical and demographic characteristics, experiences in the treatment].

PubMed

Csoma, Zsanett Renáta; Dalmády, Szandra; Ábrahám, Rita; Rózsa, Tamás; Rácz, Katalin; Kemény, Lajos

2017-10-01

Infantile haemangiomas are the most common vascular tumours of infancy. The vast majority of the lesions do not require dermatological treatment due to their unique clinical course and the high rate of spontaneous regression. Approximately 10-15% of the tumours result in severe complications and sequale, requiring special management and close follow-up. The aim of the present study was to assess the data of the patients treated with infantile haemangiomas, and to summarize the results of the therapy during 4.5 years of study period, in the Paediatric Dermatology Outpatient Clinic of the Department of Dermatology and Allergology, at the University of Szeged. Demographic data of the infants (gender, gestational age and weight, perinatal history of the infant and medical history of mothers), exact date of the visits at Paediatric Dermatology Outpatient Clinic and tumour characteristics (number, subtype, anatomical localisation and complications) were analysed in details. Treatment modalities and therapy intervals, outcomes and the adverse events of the therapies were also discussed in the survey. During the study period, 96 infants with 163 infantile haemangiomas were observed. 54 patients required regular observations, while 42 infants required local or systemic beta-blocker therapy. All of the tumours treated with local or systemic therapy showed marked clinical regression; adverse effects were observed in only 6 cases. The gestational age and gestational weight of infants requiring beta-blocker therapy was significantly lower as compared to children needed only observation. Systemic propranolol is currently the first-line treatment modality for complicated infantile haemangiomas. Our results confirm the significant therapeutic efficacy of propranolol. Early introduction of the treatment is relevant; unfortunately a great proportion of patients are referred late to Paediatric Dermatology Centres. Orv Hetil. 2017; 158(39): 1535-1544.

Structures and Materials Technologies for Extreme Environments Applied to Reusable Launch Vehicles

NASA Technical Reports Server (NTRS)

Scotti, Stephen J.; Clay, Christopher; Rezin, Marc

2003-01-01

This paper provides an overview of the evolution of structures and materials technology approaches to survive the challenging extreme environments encountered by earth-to-orbit space transportation systems, with emphasis on more recent developments in the USA. The evolution of technology requirements and experience in the various approaches to meeting these requirements has significantly influenced the technology approaches. While previous goals were primarily performance driven, more recently dramatic improvements in costs/operations and in safety have been paramount goals. Technologies that focus on the cost/operations and safety goals in the area of hot structures and thermal protection systems for reusable launch vehicles are presented. Assessments of the potential ability of the various technologies to satisfy the technology requirements, and their current technology readiness status are also presented.

The Joint Capabilities Integration and Development System: Its Impact on Air Force Acquisition Thirteen Years Later

DTIC Science & Technology

2016-08-01

area denial environments . Near peer adversaries continue to develop low observable aircraft , proliferate counter-precision guided munition systems ...when the Air Force had significantly more control over its requirements validation and acquisition processes. The only tactical aircraft currently in... systems such as the F-35A. Interestingly, upgrades to these previously fielded aircraft also take longer after JCIDS was implemented than it did to

A Cost Prediction Model for Electronic Systems Flight Test Costs.

DTIC Science & Technology

1983-09-01

development. It was found that a significant cost estimating relationship (CER) exists between costs and the characteristics of the flight test design. Using...University In Partial Fulfillment of the Requirements for the Degree of Master of Science in Systems Management By C ., Thomas 3. DuPre’, BS Accession...SYSTEMS MANAGEMENT DATE: 28 September 1983 COMMITTEE CHA. ICEAfER it TABLE OF CONTENTS Page LIST OF TABLES ......................... vi LIST OF FIGURES

Technology update: Tethered aerostat structural design and material developments

NASA Technical Reports Server (NTRS)

Witherow, R. G.

1975-01-01

Requirements exist for an extremely stable, high performance, all-weather tethered aerostat system. This requirement has been satisfied by a 250,000 cubic foot captive buoyant vehicle as demonstrated by over a year of successful field operations. This achievement required significant advancements in several technology areas including composite materials design, aerostatics and aerodynamics, structural design, electro-mechanical design, vehicle fabrication and mooring operations. This paper specifically addresses the materials and structural design aspects of pressurized buoyant vehicles as related to the general class of Lighter Than Air vehicles.

A Turbo-Brayton Cryocooler for Aircraft Superconducting Systems

NASA Technical Reports Server (NTRS)

Dietz, Anthony

2014-01-01

Hybrid turboelectric aircraft-with gas turbines driving electric generators connected to electric propulsion motors-have the potential to transform aircraft design. Decoupling power generation from propulsion enables innovative aircraft designs, such as blended-wing bodies, with distributed propulsion. These hybrid turboelectric aircraft have the potential to significantly reduce emissions, decrease fuel burn, and reduce noise, all of which are required to make air transportation growth projections sustainable. The power density requirements for these electric machines can only be achieved with superconductors, which in turn require lightweight, high-capacity cryocoolers.

Reports and Testimony: March 1992

DTIC Science & Technology

1992-03-01

pesticide data needs, it is essential that an interaigency strategy guide the progrmn. Otherwise, USDA may be jeopardizing a significant federal...assess the effectiveness of Job Opportunities and Basic Skills Training (JoBs) programs run by Indian Tribes and Alaska Native groups or determine...contractor reporting requirements. irr’s efforts to develop automation systems continue to disappoint. Major systems are plagued by basic problems, including

Trajectories of Engagement: A Repeated Cross-Sectional Investigation of Student Perceptions of an Online Learning Environment

ERIC Educational Resources Information Center

Palmer, Stuart; Holt, Dale

2012-01-01

Evaluations of online learning environments (OLEs) often present a snapshot of system use. It has been identified in the literature that extended evaluation is required to reveal statistically significant developments in the evolution of system use over time. The research presented here draws on student OLE evaluations surveys run over the period…

Addressing An Audience: A Study of Expert-Novice Differences in Writing. Technical Report No. 3.

ERIC Educational Resources Information Center

Atlas, Marshall A.

To investigate differences in the writing processes of novice and expert writers, a test of writing skills was developed that required subjects to write a business letter in defense of a particular system of public transportation in response to a letter objecting to that system. In the first of three experiments, significant differences were found…

Does a new steam meal catering system meet patient requirements in hospital?

PubMed

Hickson, M; Fearnley, L; Thomas, J; Evans, S

2007-10-01

It has been consistently observed that a significant proportion of hospital inpatients are malnourished and many actually develop malnutrition in hospital. The NHS provides over 300 million meals each year at a cost of pound 500 million, yet there is relatively little research evaluating how well different catering systems provide for the needs of hospital inpatients. The aim of the study was to: (i) evaluate whether a new steam meal catering system (Steamplicity) enables patients in theory to meet their energy requirements in hospital and (ii) compare energy and protein intake using Steamplicity with a traditional bulk cook-chill system. Patients not at nutritional risk had their food intake at one lunchtime assessed. Energy intake was compared with the patients' energy requirements and energy and protein intake were compared with previous data from a bulk system. Fifty-seven patients had a median daily energy requirement of 7648 kJ (1821 kcal) [inter-quartile range (IQR): 6854-9164 kJ]. Assuming 30% [2293 kJ (546 kcal)] should be supplied by the lunch meal the average intake of 1369 kJ (326 kcal) fell short by 40%. Patients served meals from Steamplicity ate less energy [1369 kJ versus 1562 kJ (326 kcal versus 372 kcal) P = 0.04] but similar protein (18 g versus 19 g P = 0.34) to the bulk system. The largest difference was the energy provided by the dessert since the bulk system served more hot high-calorie desserts. Patient intakes did not meet their estimated requirements. The patients in this study were eating well and not at nutritional risk, thus patients with a poor appetite will be even less likely to meet their nutritional requirements. Steamplicity meals result in a lower energy intake than meals from a bulk cook-chill system, but similar protein intakes.

Solenoid Magnet System for the Fermilab Mu2e Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lamm, M. J.; Andreev, N.; Ambrosio, G.

2011-12-14

The Fermilab Mu2e experiment seeks to measure the rare process of direct muon to electron conversion in the field of a nucleus. Key to the design of the experiment is a system of three superconducting solenoids; a muon production solenoid (PS) which is a 1.8 m aperture axially graded solenoid with a peak field of 5 T used to focus secondary pions and muons from a production target located in the solenoid aperture; an 'S shaped' transport solenoid (TS) which selects and transports the subsequent muons towards a stopping target; a detector solenoid (DS) which is an axially graded solenoidmore » at the upstream end to focus transported muons to a stopping target, and a spectrometer solenoid at the downstream end to accurately measure the momentum of the outgoing conversion elections. The magnetic field requirements, the significant magnetic coupling between the solenoids, the curved muon transport geometry and the large beam induced energy deposition into the superconducting coils pose significant challenges to the magnetic, mechanical, and thermal design of this system. In this paper a conceptual design for the magnetic system which meets the Mu2e experiment requirements is presented.« less

The reusable launch vehicle technology program

NASA Astrophysics Data System (ADS)

Cook, S.

Today's launch systems have major shortcomings that will increase in significance in the future, and thus are principal drivers for seeking major improvements in space transportation. They are too costly; insufficiently reliable, safe, and operable; and increasingly losing market share to international competition. For the United States to continue its leadership in the human exploration and wide ranging utilization of space, the first order of business must be to achieve low cost, reliable transportatin to Earth orbit. NASA's Access to Space Study, in 1993, recommended the development of a fully reusable single-stage-to-orbit (SSTO) rocket vehicle as an Agency goal. The goal of the Reusable Launch Vehicle (RLV) technology program is to mature the technologies essential for a next-generation reusable launch system capable of reliably serving National space transportation needs at substantially reduced costs. The primary objectives of the RLV technology program are to (1) mature the technologies required for the next-generation system, (2) demonstrate the capability to achieve low development and operational cost, and rapid launch turnaround times and (3) reduce business and technical risks to encourage significant private investment in the commercial development and operation of the next-generation system. Developing and demonstrating the technologies required for a Single Stage to Orbit (SSTO) rocket is a focus of the program becuase past studies indicate that it has the best potential for achieving the lowest space access cost while acting as an RLV technology driver (since it also encompasses the technology requirements of reusable rocket vehicles in general).

The reusable launch vehicle technology program

NASA Technical Reports Server (NTRS)

Cook, S.

1995-01-01

Today's launch systems have major shortcomings that will increase in significance in the future, and thus are principal drivers for seeking major improvements in space transportation. They are too costly; insufficiently reliable, safe, and operable; and increasingly losing market share to international competition. For the United States to continue its leadership in the human exploration and wide ranging utilization of space, the first order of business must be to achieve low cost, reliable transportatin to Earth orbit. NASA's Access to Space Study, in 1993, recommended the development of a fully reusable single-stage-to-orbit (SSTO) rocket vehicle as an Agency goal. The goal of the Reusable Launch Vehicle (RLV) technology program is to mature the technologies essential for a next-generation reusable launch system capable of reliably serving National space transportation needs at substantially reduced costs. The primary objectives of the RLV technology program are to (1) mature the technologies required for the next-generation system, (2) demonstrate the capability to achieve low development and operational cost, and rapid launch turnaround times and (3) reduce business and technical risks to encourage significant private investment in the commercial development and operation of the next-generation system. Developing and demonstrating the technologies required for a Single Stage to Orbit (SSTO) rocket is a focus of the program becuase past studies indicate that it has the best potential for achieving the lowest space access cost while acting as an RLV technology driver (since it also encompasses the technology requirements of reusable rocket vehicles in general).

Using a modification of the Clavien-Dindo system accounting for readmissions and multiple interventions: defining quality for pancreaticoduodenectomy.

PubMed

Baker, Marshall S; Sherman, Karen L; Stocker, Susan J; Hayman, Amanda V; Bentrem, David J; Prinz, Richard A; Talamonti, Mark S

2014-09-01

The Clavien-Dindo system (CD) does not change the grade assigned a complication when multiple readmissions or interventions are required to manage a complication. We apply a modification of CD accounting for readmissions and interventions to pancreaticoduodenectomy (PD). PDs done between 1999 and 2009 were reviewed. CD grade IIIa complications requiring more than one intervention and II and IIIa complications requiring significantly prolonged lengths of stay including all 90-day readmissions were classified severe-adverse-postoperative-outcomes (SAPO). CD IIIb, IV, and V complications were also classified SAPOs. All other complications were considered minor-adverse-postoperative-outcomes (MAPO). Four-hundred forty three of 490 PD patients (90.4%) had either no complication or a complication of low to moderate CD grade (I, II, IIIa). When reclassified by the new metric, 92 patient-outcomes (19%) were upgraded from CD II or IIIa to SAPO. One-hundred thirty nine patients (28.4%) had a SAPO. Multivariable regression identified age >75 years, pylorus preservation and operative blood loss >1,500 ml as predictors of SAPO. Age was not associated with poor outcome using the unmodified CD system. Established systems may under-grade the severity of some complications following PD. We define a procedure-specific modification of CD accounting for readmissions and multiple interventions. Using this modification, advanced age, pylorus preservation, and significant blood loss are associated with poor outcome. © 2014 Wiley Periodicals, Inc.

Environmental Information for the U.S. Next Generation Air Transportation System (NextGen)

NASA Astrophysics Data System (ADS)

Murray, J.; Miner, C.; Pace, D.; Minnis, P.; Mecikalski, J.; Feltz, W.; Johnson, D.; Iskendarian, H.; Haynes, J.

2009-09-01

It is estimated that weather is responsible for approximately 70% of all air traffic delays and cancellations in the United States. Annually, this produces an overall economic loss of nearly 40B. The FAA and NASA have determined that weather impacts and other environmental constraints on the U.S. National Airspace System (NAS) will increase to the point of system unsustainability unless the NAS is radically transformed. A Next Generation Air Transportation System (NextGen) is planned to accommodate the anticipated demand for increased system capacity and the super-density operations that this transformation will entail. The heart of the environmental information component that is being developed for NextGen will be a 4-dimensional data cube which will include a single authoritative source comprising probabilistic weather information for NextGen Air Traffic Management (ATM) systems. Aviation weather constraints and safety hazards typically comprise meso-scale, storm-scale and microscale observables that can significantly impact both terminal and enroute aviation operations. With these operational impacts in mind, functional and performance requirements for the NextGen weather system were established which require significant improvements in observation and forecasting capabilities. This will include satellite observations from geostationary and/or polar-orbiting hyperspectral sounders, multi-spectral imagers, lightning mappers, space weather monitors and other environmental observing systems. It will also require improved in situ and remotely sensed observations from ground-based and airborne systems. These observations will be used to better understand and to develop forecasting applications for convective weather, in-flight icing, turbulence, ceilings and visibility, volcanic ash, space weather and the environmental impacts of aviation. Cutting-edge collaborative research efforts and results from NASA, NOAA and the FAA which address these phenomena are summarized. In 2003, a Joint Planning and Development Office (JPDO) was established by public law to meet the significant challenges that NextGen presents. JPDO partners were chartered which include, but are not limited to, the Federal Aviation Administration (FAA), the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), the Department of Defense (DOD) and broad elements of academia and the aviation industry. This paper provides the aviation meteorology community with useful insight on salient NextGen environmental information requirements that have been developed by the JPDO Weather Working Group's Environmental Information Team. These efforts will help to define observation and forecast systems needed to support NextGen and to develop the operational applications for NextGen aviation weather information. Another major goal of this paper is to inform the international weather community of our research progress and plans for NextGen, to foster research collaboration with our colleagues, and to exchange information to maximize success of NextGen, SESAR and related initiatives world-wide.

FPGA cluster for high-performance AO real-time control system

NASA Astrophysics Data System (ADS)

Geng, Deli; Goodsell, Stephen J.; Basden, Alastair G.; Dipper, Nigel A.; Myers, Richard M.; Saunter, Chris D.

2006-06-01

Whilst the high throughput and low latency requirements for the next generation AO real-time control systems have posed a significant challenge to von Neumann architecture processor systems, the Field Programmable Gate Array (FPGA) has emerged as a long term solution with high performance on throughput and excellent predictability on latency. Moreover, FPGA devices have highly capable programmable interfacing, which lead to more highly integrated system. Nevertheless, a single FPGA is still not enough: multiple FPGA devices need to be clustered to perform the required subaperture processing and the reconstruction computation. In an AO real-time control system, the memory bandwidth is often the bottleneck of the system, simply because a vast amount of supporting data, e.g. pixel calibration maps and the reconstruction matrix, need to be accessed within a short period. The cluster, as a general computing architecture, has excellent scalability in processing throughput, memory bandwidth, memory capacity, and communication bandwidth. Problems, such as task distribution, node communication, system verification, are discussed.

Flight evaluation of a computer aided low-altitude helicopter flight guidance system

NASA Technical Reports Server (NTRS)

Swenson, Harry N.; Jones, Raymond D.; Clark, Raymond

1993-01-01

The Flight Systems Development branch of the U.S. Army's Avionics Research and Development Activity (AVRADA) and NASA Ames Research Center developed for flight testing a Computer Aided Low-Altitude Helicopter Flight (CALAHF) guidance system. The system includes a trajectory-generation algorithm which uses dynamic programming and a helmet-mounted display (HMD) presentation of a pathway-in-the-sky, a phantom aircraft, and flight-path vector/predictor guidance symbology. The trajectory-generation algorithm uses knowledge of the global mission requirements, a digital terrain map, aircraft performance capabilities, and precision navigation information to determine a trajectory between mission waypoints that seeks valleys to minimize threat exposure. This system was developed and evaluated through extensive use of piloted simulation and has demonstrated a 'pilot centered' concept of automated and integrated navigation and terrain mission planning flight guidance. This system has shown a significant improvement in pilot situational awareness, and mission effectiveness as well as a decrease in training and proficiency time required for a near terrain, nighttime, adverse weather system.

Observing System Simulations for the NASA ASCENDS Lidar CO2 Mission Concept: Substantiating Science Measurement Requirements

NASA Technical Reports Server (NTRS)

Kawa, Stephan R.; Baker, David Frank; Schuh, Andrew E.; Abshire, James Brice; Browell, Edward V.; Michalak, Anna M.

2012-01-01

The NASA ASCENDS mission (Active Sensing of Carbon Emissions, Nights, Days, and Seasons) is envisioned as the next generation of dedicated, space-based CO2 observing systems, currently planned for launch in about the year 2022. Recommended by the US National Academy of Sciences Decadal Survey, active (lidar) sensing of CO2 from space has several potentially significant advantages, in comparison to current and planned passive CO2 instruments, that promise to advance CO2 measurement capability and carbon cycle understanding into the next decade. Assessment and testing of possible lidar instrument technologies indicates that such sensors are more than feasible, however, the measurement precision and accuracy requirements remain at unprecedented levels of stringency. It is, therefore, important to quantitatively and consistently evaluate the measurement capabilities and requirements for the prospective active system in the context of advancing our knowledge of carbon flux distributions and their dependence on underlying physical processes. This amounts to establishing minimum requirements for precision, relative accuracy, spatial/temporal coverage and resolution, vertical information content, interferences, and possibly the tradeoffs among these parameters, while at the same time framing a mission that can be implemented within a constrained budget. Here, we present results of observing system simulation studies, commissioned by the ASCENDS Science Requirements Definition Team, for a range of possible mission implementation options that are intended to substantiate science measurement requirements for a laser-based CO2 space instrument.

A web-based system for supporting global land cover data production

NASA Astrophysics Data System (ADS)

Han, Gang; Chen, Jun; He, Chaoying; Li, Songnian; Wu, Hao; Liao, Anping; Peng, Shu

2015-05-01

Global land cover (GLC) data production and verification process is very complicated, time consuming and labor intensive, requiring huge amount of imagery data and ancillary data and involving many people, often from different geographic locations. The efficient integration of various kinds of ancillary data and effective collaborative classification in large area land cover mapping requires advanced supporting tools. This paper presents the design and development of a web-based system for supporting 30-m resolution GLC data production by combining geo-spatial web-service and Computer Support Collaborative Work (CSCW) technology. Based on the analysis of the functional and non-functional requirements from GLC mapping, a three tiers system model is proposed with four major parts, i.e., multisource data resources, data and function services, interactive mapping and production management. The prototyping and implementation of the system have been realised by a combination of Open Source Software (OSS) and commercially available off-the-shelf system. This web-based system not only facilitates the integration of heterogeneous data and services required by GLC data production, but also provides online access, visualization and analysis of the images, ancillary data and interim 30 m global land-cover maps. The system further supports online collaborative quality check and verification workflows. It has been successfully applied to China's 30-m resolution GLC mapping project, and has improved significantly the efficiency of GLC data production and verification. The concepts developed through this study should also benefit other GLC or regional land-cover data production efforts.

Next generation space interconnect research and development in space communications

NASA Astrophysics Data System (ADS)

Collier, Charles Patrick

2017-11-01

Interconnect or "bus" is one of the critical technologies in design of spacecraft avionics systems that dictates its architecture and complexity. MIL-STD-1553B has long been used as the avionics backbone technology. As avionics systems become more and more capable and complex, however, limitations of MIL-STD-1553B such as insufficient 1 Mbps bandwidth and separability have forced current avionics architects and designers to use combination of different interconnect technologies in order to meet various requirements: CompactPCI is used for backplane interconnect; LVDS or RS422 is used for low and high-speed direct point-to-point interconnect; and some proprietary interconnect standards are designed for custom interfaces. This results in a very complicated system that consumes significant spacecraft mass and power and requires extensive resources in design, integration and testing of spacecraft systems.

The effect of low velocity impact in the strength characteristics of composite materials laminates

NASA Technical Reports Server (NTRS)

Liebowitz, H.

1983-01-01

The nonlinear vibration response of a double cantilevered beam subjected to pulse loading over a central sector is studied. The initial response is generated in detail to ascertain the energetics of the response. The total energy is used as a gauge of the stability and accuracy of the solution. It is shown that to obtain accurate and stable initial solutions an extremely high spatial and time resolution is required. This requirement was only evident through an examination of the energy of the system. It is proposed, therefore, to use the total energy of the system as a necessary stability and accuracy criterion for the nonlinear response of conservative systems. The results also demonstrate that even for moderate nonlinearities, the effects of membrane forces have a significant influence on the system.

Fly-by-light flight control system technology development plan

NASA Technical Reports Server (NTRS)

Chakravarty, A.; Berwick, J. W.; Griffith, D. M.; Marston, S. E.; Norton, R. L.

1990-01-01

The results of a four-month, phased effort to develop a Fly-by-Light Technology Development Plan are documented. The technical shortfalls for each phase were identified and a development plan to bridge the technical gap was developed. The production configuration was defined for a 757-type airplane, but it is suggested that the demonstration flight be conducted on the NASA Transport Systems Research Vehicle. The modifications required and verification and validation issues are delineated in this report. A detailed schedule for the phased introduction of fly-by-light system components has been generated. It is concluded that a fiber-optics program would contribute significantly toward developing the required state of readiness that will make a fly-by-light control system not only cost effective but reliable without mitigating the weight and high-energy radio frequency related benefits.

Design and Integration of an All-Magnetic Attitude Control System for FASTSAT-HSV01's Multiple Pointing Objectives

NASA Technical Reports Server (NTRS)

DeKock, Brandon; Sanders, Devon; Vanzwieten, Tannen; Capo-Lugo, Pedro

2011-01-01

The FASTSAT-HSV01 spacecraft is a microsatellite with magnetic torque rods as it sole attitude control actuator. FASTSAT s multiple payloads and mission functions require the Attitude Control System (ACS) to maintain Local Vertical Local Horizontal (LVLH)-referenced attitudes without spin-stabilization, while the pointing errors for some attitudes be significantly smaller than the previous best-demonstrated for this type of control system. The mission requires the ACS to hold multiple stable, unstable, and non-equilibrium attitudes, as well as eject a 3U CubeSat from an onboard P-POD and recover from the ensuing tumble. This paper describes the Attitude Control System, the reasons for design choices, how the ACS integrates with the rest of the spacecraft, and gives recommendations for potential future applications of the work.

A computerized assessment to compare the impact of standard, stereoscopic, and high-definition laparoscopic monitor displays on surgical technique.

PubMed

Feng, Chuan; Rozenblit, Jerzy W; Hamilton, Allan J

2010-11-01

Surgeons performing laparoscopic surgery have strong biases regarding the quality and nature of the laparoscopic video monitor display. In a comparative study, we used a unique computerized sensing and analysis system to evaluate the various types of monitors employed in laparoscopic surgery. We compared the impact of different types of monitor displays on an individual's performance of a laparoscopic training task which required the subject to move the instrument to a set of targets. Participants (varying from no laparoscopic experience to board-certified surgeons) were asked to perform the assigned task while using all three display systems, which were randomly assigned: a conventional laparoscopic monitor system (2D), a high-definition monitor system (HD), and a stereoscopic display (3D). The effects of monitor system on various performance parameters (total time consumed to finish the task, average speed, and movement economy) were analyzed by computer. Each of the subjects filled out a subjective questionnaire at the end of their training session. A total of 27 participants completed our study. Performance with the HD monitor was significantly slower than with either the 3D or 2D monitor (p < 0.0001). Movement economy with the HD monitor was significantly reduced compared with the 3D (p < 0.0004) or 2D (p < 0.0001) monitor. In terms of average time required to complete the task, performance with the 3D monitor was significantly faster than with the HD (p < 0.0001) or 2D (p < 0.0086) monitor. However, the HD system was the overwhelming favorite according to subjective evaluation. Computerized sensing and analysis is capable of quantitatively assessing the seemingly minor effect of monitor display on surgical training performance. The study demonstrates that, while users expressed a decided preference for HD systems, actual quantitative analysis indicates that HD monitors offer no statistically significant advantage and may even worsen performance compared with standard 2D or 3D laparoscopic monitors.

The experience of living with stroke and using technology: opportunities to engage and co-design with end users.

PubMed

Nasr, Nasrin; Leon, Beatriz; Mountain, Gail; Nijenhuis, Sharon M; Prange, Gerdienke; Sale, Patrizio; Amirabdollahian, Farshid

2016-11-01

We drew on an interdisciplinary research design to examine stroke survivors' experiences of living with stroke and with technology in order to provide technology developers with insight into values, thoughts and feelings of the potential users of a to-be-designed robotic technology for home-based rehabilitation of the hand and wrist. Ten stroke survivors and their family carers were purposefully selected. On the first home visit, they were introduced to cultural probe. On the second visit, the content of the probe packs were used as prompt to conduct one-to-one interviews with them. The data generated was analysed using thematic analysis. A third home visit was conducted to evaluate the early prototype. User requirements were categorised into their network of relationships, their attitude towards technology, their skills, their goals and motivations. The user requirements were used to envision the requirements of the system including providing feedback on performance, motivational aspects and usability of the system. Participants' views on the system requirements were obtained during a participatory evaluation. This study showed that prior to the development of technology, it is important to engage with potential users to identify user requirements and subsequently envision system requirements based on users' views. Implications for Rehabilitation An understanding of how stroke survivors make sense of their experiences of living with stroke is needed to design home-based rehabilitation technologies. Linking stroke survivors' goals, motivations, behaviour, feelings and attitude to user requirements prior to technology development has a significant impact on improving the design.

Study on key technologies of vehicle networking system platform for electric automobiles based on micro-service

NASA Astrophysics Data System (ADS)

Ye, Fei

2018-04-01

With the rapid increase of electric automobiles and charging piles, the elastic expansion and online rapid upgrade were required for the vehicle networking system platform (system platform for short). At present, it is difficult to meet the operation needs due to the traditional huge rock architecture used by the system platform. This paper studied the system platform technology architecture based on "cloud platform +micro-service" to obtain a new generation of vehicle networking system platform with the combination of elastic expansion and application, thus significantly improving the service operation ability of system.

A Self-Tuning Kalman Filter for Autonomous Navigation Using the Global Positioning System (GPS)

NASA Technical Reports Server (NTRS)

Truong, Son H.

1999-01-01

Most navigation systems currently operated by NASA are ground-based, and require extensive support to produce accurate results. Recently developed systems that use Kalman filter and GPS (Global Positioning Systems) data for orbit determination greatly reduce dependency on ground support, and have potential to provide significant economies for NASA spacecraft navigation. These systems, however, still rely on manual tuning from analysts. A sophisticated neuro-fuzzy component fully integrated with the flight navigation system can perform the self-tuning capability for the Kalman filter and help the navigation system recover from estimation errors in real time.

Reliability and cost evaluation of small isolated power systems containing photovoltaic and wind energy

NASA Astrophysics Data System (ADS)

Karki, Rajesh

Renewable energy application in electric power systems is growing rapidly worldwide due to enhanced public concerns for adverse environmental impacts and escalation in energy costs associated with the use of conventional energy sources. Photovoltaics and wind energy sources are being increasingly recognized as cost effective generation sources. A comprehensive evaluation of reliability and cost is required to analyze the actual benefits of utilizing these energy sources. The reliability aspects of utilizing renewable energy sources have largely been ignored in the past due the relatively insignificant contribution of these sources in major power systems, and consequently due to the lack of appropriate techniques. Renewable energy sources have the potential to play a significant role in the electrical energy requirements of small isolated power systems which are primarily supplied by costly diesel fuel. A relatively high renewable energy penetration can significantly reduce the system fuel costs but can also have considerable impact on the system reliability. Small isolated systems routinely plan their generating facilities using deterministic adequacy methods that cannot incorporate the highly erratic behavior of renewable energy sources. The utilization of a single probabilistic risk index has not been generally accepted in small isolated system evaluation despite its utilization in most large power utilities. Deterministic and probabilistic techniques are combined in this thesis using a system well-being approach to provide useful adequacy indices for small isolated systems that include renewable energy. This thesis presents an evaluation model for small isolated systems containing renewable energy sources by integrating simulation models that generate appropriate atmospheric data, evaluate chronological renewable power outputs and combine total available energy and load to provide useful system indices. A software tool SIPSREL+ has been developed which generates risk, well-being and energy based indices to provide realistic cost/reliability measures of utilizing renewable energy. The concepts presented and the examples illustrated in this thesis will help system planners to decide on appropriate installation sites, the types and mix of different energy generating sources, the optimum operating policies, and the optimum generation expansion plans required to meet increasing load demands in small isolated power systems containing photovoltaic and wind energy sources.

Scaling and Optimization of Magnetic Refrigeration for Commercial Building HVAC Systems Greater than 175 kW in Capacity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdelaziz, Omar; West, David L; Mallow, Anne M

Heating, ventilation, air-conditioning and refrigeration (HVACR) account for approximately one- third of building energy consumption. Magnetic refrigeration presents an opportunity for significant energy savings and emissions reduction for serving the building heating, cooling, and refrigeration loads. In this paper, we have examined the magnet and MCE material requirements for scaling magnetic refrigeration systems for commercial building cooling applications. Scaling relationships governing the resources required for magnetic refrigeration systems have been developed. As system refrigeration capacity increases, the use of superconducting magnet systems becomes more applicable, and a comparison is presented of system requirements for permanent and superconducting (SC) magnetization systems.more » Included in this analysis is an investigation of the ability of superconducting magnet based systems to overcome the parasitic power penalty of the cryocooler used to keep SC windings at cryogenic temperatures. Scaling relationships were used to develop the initial specification for a SC magnet-based active magnetic regeneration (AMR) system. An optimized superconducting magnet was designed to support this system. In this analysis, we show that the SC magnet system consisting of two 0.38 m3 regenerators is capable of producing 285 kW of cooling power with a T of 28 K. A system COP of 4.02 including cryocooler and fan losses which illustrates that an SC magnet-based system can operate with efficiency comparable to traditional systems and deliver large cooling powers of 285.4 kW (81.2 Tons).« less

An assessment of the real-time application capabilities of the SIFT computer system

NASA Technical Reports Server (NTRS)

Butler, R. W.

1982-01-01

The real-time capabilities of the SIFT computer system, a highly reliable multicomputer architecture developed to support the flight controls of a relaxed static stability aircraft, are discussed. The SIFT computer system was designed to meet extremely high reliability requirements and to facilitate a formal proof of its correctness. Although SIFT represents a significant achievement in fault-tolerant system research it presents an unusual and restrictive interface to its users. The characteristics of the user interface and its impact on application system design are assessed.

Public health systems research: the state of the field.

PubMed

Bagley, Prue; Lin, Vivian

2008-11-01

Public health infrastructure provides the building blocks required for the system to achieve public health goals. A systems approach to public health has been suggested as a means to tackle persistent and emerging problems. Systems and infrastructure are attracting increased research attention. A review of the Australian and international literature suggests an absence of empirical evidence about how the system and its component parts does, or should, work and highlights some of the difficulties associated with generating such evidence. It also indicates there is significant scope for further research.

In Silico Dynamics: computer simulation in a Virtual Embryo (SOT)

EPA Science Inventory

Abstract: Utilizing cell biological information to predict higher order biological processes is a significant challenge in predictive toxicology. This is especially true for highly dynamical systems such as the embryo where morphogenesis, growth and differentiation require preci...

A non-laser light source for photodynamic therapy: in vitro effects on normal and malignant cells.

PubMed

Kashtan, Hanoch; Haddad, Riad; Greenberg, Ron; Skornick, Yehuda; Kaplan, Ofer

2002-01-01

Photodynamic therapy (PDT) involves the use of photosensitizing drugs combined with light to treat tumors. Laser systems, the current source of light for PDT, have several inherent drawbacks: the spectrum is essentially monochromatic which may be problematic for second generation photosensitizers, the systems are bulky and nearly impossible to move between hospital locations and require complicated electrical and cooling installations, the cost of a typical system is enormous, and its maintenance and operation require highly trained personnel. We now introduce a new non-laser light system, Versa-Light, which appears to work as effectively and has none of the above drawbacks. A series of in vitro studies were performed using various murine and human normal and cancer cells which underwent PDT using aluminum phthalocyanine (AlPcS4) as a photosensitizer and Versa-Light as the light source. PDT of cancer cells at light energy levels of 50, 100 and 200 j/cm2 significantly decreased cell viability. PDT also decreased cell viability of normal murine splenocytes and normal human lymphocytes, but to a lesser extent. The observed significant hyperthermia was light dose-dependent. We believe that Versa-Light can replace laser systems as an enhanced light source for PDT. Further in vitro and pre-clinical studies are in progress.

Hazard Analysis and Safety Requirements for Small Drone Operations: To What Extent Do Popular Drones Embed Safety?

PubMed

Plioutsias, Anastasios; Karanikas, Nektarios; Chatzimihailidou, Maria Mikela

2018-03-01

Currently, published risk analyses for drones refer mainly to commercial systems, use data from civil aviation, and are based on probabilistic approaches without suggesting an inclusive list of hazards and respective requirements. Within this context, this article presents: (1) a set of safety requirements generated from the application of the systems theoretic process analysis (STPA) technique on a generic small drone system; (2) a gap analysis between the set of safety requirements and the ones met by 19 popular drone models; (3) the extent of the differences between those models, their manufacturers, and the countries of origin; and (4) the association of drone prices with the extent they meet the requirements derived by STPA. The application of STPA resulted in 70 safety requirements distributed across the authority, manufacturer, end user, or drone automation levels. A gap analysis showed high dissimilarities regarding the extent to which the 19 drones meet the same safety requirements. Statistical results suggested a positive correlation between drone prices and the extent that the 19 drones studied herein met the safety requirements generated by STPA, and significant differences were identified among the manufacturers. This work complements the existing risk assessment frameworks for small drones, and contributes to the establishment of a commonly endorsed international risk analysis framework. Such a framework will support the development of a holistic and methodologically justified standardization scheme for small drone flights. © 2017 Society for Risk Analysis.

Nuclear electric propulsion development and qualification facilities

NASA Technical Reports Server (NTRS)

Dutt, D. S.; Thomassen, K.; Sovey, J.; Fontana, Mario

1991-01-01

This paper summarizes the findings of a Tri-Agency panel consisting of members from the National Aeronautics and Space Administration (NASA), U.S. Department of Energy (DOE), and U.S. Department of Defense (DOD) that were charged with reviewing the status and availability of facilities to test components and subsystems for megawatt-class nuclear electric propulsion (NEP) systems. The facilities required to support development of NEP are available in NASA centers, DOE laboratories, and industry. However, several key facilities require significant and near-term modification in order to perform the testing required to meet a 2014 launch date. For the higher powered Mars cargo and piloted missions, the priority established for facility preparation is: (1) a thruster developmental testing facility, (2) a thruster lifetime testing facility, (3) a dynamic energy conversion development and demonstration facility, and (4) an advanced reactor testing facility (if required to demonstrate an advanced multiwatt power system). Facilities to support development of the power conditioning and heat rejection subsystems are available in industry, federal laboratories, and universities. In addition to the development facilities, a new preflight qualifications and acceptance testing facility will be required to support the deployment of NEP systems for precursor, cargo, or piloted Mars missions. Because the deployment strategy for NEP involves early demonstration missions, the demonstration of the SP-100 power system is needed by the early 2000's.

Megawatt solar power systems for lunar surface operations

NASA Technical Reports Server (NTRS)

Adams, Brian; Alhadeff, Sam; Beard, Shawn; Carlile, David; Cook, David; Douglas, Craig; Garcia, Don; Gillespie, David; Golingo, Raymond; Gonzalez, Drew

1990-01-01

Lunar surface operations require habitation, transportation, life support, scientific, and manufacturing systems, all of which require some form of power. As an alternative to nuclear power, the development of a modular one megawatt solar power system is studied, examining both photovoltaic and dynamic cycle conversion methods, along with energy storage, heat rejection, and power backup subsystems. For photovoltaic power conversion, two systems are examined. First, a substantial increase in photovoltaic conversion efficiency is realized with the use of new GaAs/GaSb tandem photovoltaic cells, offering an impressive overall array efficiency of 23.5 percent. Since these new cells are still in the experimental phase of development, a currently available GaAs cell providing 18 percent efficiency is examined as an alternate to the experimental cells. Both Brayton and Stirling cycles, powered by linear parabolic solar concentrators, are examined for dynamic cycle power conversion. The Brayton cycle is studied in depth since it is already well developed and can provide high power levels fairly efficiently in a compact, low mass system. The dynamic conversion system requires large scale waste heat rejection capability. To provide this heat rejection, a comparison is made between a heat pipe/radiative fin system using advanced composites, and a potentially less massive liquid droplet radiator system. To supply power through the lunar night, both a low temperature alkaline fuel cell system and an experimental high temperature monolithic solid-oxide fuel cell system are considered. The reactants for the fuel cells are stored cryogenically in order to avoid the high tankage mass required by conventional gaseous storage. In addition, it is proposed that the propellant tanks from a spent, prototype lunar excursion vehicle be used for this purpose, therefore resulting in a significant overall reduction in effective storage system mass.

Comparison of two humidification systems for long-term noninvasive mechanical ventilation.

PubMed

Nava, S; Cirio, S; Fanfulla, F; Carlucci, A; Navarra, A; Negri, A; Ceriana, P

2008-08-01

There is no consensus concerning the best system of humidification during long-term noninvasive mechanical ventilation (NIMV). In a technical pilot randomised crossover 12-month study, 16 patients with stable chronic hypercapnic respiratory failure received either heated humidification or heat and moisture exchanger. Compliance with long-term NIMV, airway symptoms, side-effects and number of severe acute pulmonary exacerbations requiring hospitalisation were recorded. Two patients died. Intention-to-treat statistical analysis was performed on 14 patients. No significant differences were observed in compliance with long-term NIMV, but 10 out of 14 patients decided to continue long-term NIMV with heated humidification at the end of the trial. The incidence of side-effects, except for dry throat (significantly more often present using heat and moisture exchanger), hospitalisations and pneumonia were not significantly different. In the present pilot study, the use heated humidification and heat and moisture exchanger showed similar tolerance and side-effects, but a higher number of patients decided to continue long-term noninvasive mechanical ventilation with heated humidification. Further larger studies are required in order to confirm these findings.

''Virtual Welding,'' a new aid for teaching Manufacturing Process Engineering

NASA Astrophysics Data System (ADS)

Portela, José M.; Huerta, María M.; Pastor, Andrés; Álvarez, Miguel; Sánchez-Carrilero, Manuel

2009-11-01

Overcrowding in the classroom is a serious problem in universities, particularly in specialties that require a certain type of teaching practice. These practices often require expenditure on consumables and a space large enough to hold the necessary materials and the materials that have already been used. Apart from the budget, another problem concerns the attention paid to each student. The use of simulation systems in the early learning stages of the welding technique can prove very beneficial thanks to error detection functions installed in the system, which provide the student with feedbach during the execution of the practice session, and the significant savings in both consumables and energy.

Prospects for low wing-loading STOL transports with ride smoothing.

NASA Technical Reports Server (NTRS)

Holloway, R. B.; Thompson, G. O.; Rohling, W. J.

1972-01-01

Airplanes with low wing-loadings provide STOL capability without reliance on auxiliary propulsion or augmented lift, but require a ride smoothing control system to provide acceptable passenger comfort. A parametric study produced a configuration having a .35 thrust-to-weight ratio and a 50 psf wing loading, and which satisfied specified mission requirements and airworthiness standards. A ride-smoothing control system (RCS) synthesis was then performed which consisted of ride quality criteria definition, RCS concept trades, and analysis of RCS performance benefits at significant flight conditions. Within the limitations of the study it is concluded that this is a viable approach to STOL airplane design.

An assessment of future computer system needs for large-scale computation

NASA Technical Reports Server (NTRS)

Lykos, P.; White, J.

1980-01-01

Data ranging from specific computer capability requirements to opinions about the desirability of a national computer facility are summarized. It is concluded that considerable attention should be given to improving the user-machine interface. Otherwise, increased computer power may not improve the overall effectiveness of the machine user. Significant improvement in throughput requires highly concurrent systems plus the willingness of the user community to develop problem solutions for that kind of architecture. An unanticipated result was the expression of need for an on-going cross-disciplinary users group/forum in order to share experiences and to more effectively communicate needs to the manufacturers.

Design of an Fiber-Coupled Laser Heterodyne Interferometer for the FLARE

NASA Astrophysics Data System (ADS)

Frank, Samuel; Yoo, Jongsoo; Ji, Hantao; Jara-Almonte, Jon

2016-10-01

The FLARE (Facility for Laboratory Reconnection Experiments), which is currently under construction at PPPL, requires a complete set of laboratory plasma diagnostics. The Langmuir probes that will be used in the device to gather local density data require a reliable interferometer system to serve as baseline for density measurement calibration. A fully fiber-coupled infrared laser heterodyne interferometer has been designed in order to serve as the primary line-integrated electron density diagnostic. Thanks to advances in the communications industry many fiber optic devices and phase detection methods have advanced significantly becoming increasingly reliable and inexpensive. Fully fiber coupling a plasma interferometer greatly simplifies alignment procedures needed since the only free space laser path needing alignment is through the plasma itself. Fiber-coupling also provides significant resistance to vibrational noise, a common problem in plasma interferometry systems. This device also uses a greatly simplified phase detection scheme in which chips, originally developed for the communications industry, capable of directly detecting the phase shift of a signal with high time resolution. The design and initial performance of the system will be discussed.

Managing the Security of Nursing Data in the Electronic Health Record

PubMed Central

Samadbeik, Mahnaz; Gorzin, Zahra; Khoshkam, Masomeh; Roudbari, Masoud

2015-01-01

Background: The Electronic Health Record (EHR) is a patient care information resource for clinicians and nursing documentation is an essential part of comprehensive patient care. Ensuring privacy and the security of health information is a key component to building the trust required to realize the potential benefits of electronic health information exchange. This study was aimed to manage nursing data security in the EHR and also discover the viewpoints of hospital information system vendors (computer companies) and hospital information technology specialists about nursing data security. Methods: This research is a cross sectional analytic-descriptive study. The study populations were IT experts at the academic hospitals and computer companies of Tehran city in Iran. Data was collected by a self-developed questionnaire whose validity and reliability were confirmed using the experts’ opinions and Cronbach’s alpha coefficient respectively. Data was analyzed through Spss Version 18 and by descriptive and analytic statistics. Results: The findings of the study revealed that user name and password were the most important methods to authenticate the nurses, with mean percent of 95% and 80%, respectively, and also the most significant level of information security protection were assigned to administrative and logical controls. There was no significant difference between opinions of both groups studied about the levels of information security protection and security requirements (p>0.05). Moreover the access to servers by authorized people, periodic security update, and the application of authentication and authorization were defined as the most basic security requirements from the viewpoint of more than 88 percent of recently-mentioned participants. Conclusions: Computer companies as system designers and hospitals information technology specialists as systems users and stakeholders present many important views about security requirements for EHR systems and nursing electronic documentation systems. Prioritizing of these requirements helps policy makers to decide what to do when planning for EHR implementation. Therefore, to make appropriate security decisions and to achieve the expected level of protection of the electronic nursing information, it is suggested to consider the priorities of both groups of experts about security principles and also discuss the issues seem to be different between two groups of participants in the research. PMID:25870490

Managing the security of nursing data in the electronic health record.

PubMed

Samadbeik, Mahnaz; Gorzin, Zahra; Khoshkam, Masomeh; Roudbari, Masoud

2015-02-01

The Electronic Health Record (EHR) is a patient care information resource for clinicians and nursing documentation is an essential part of comprehensive patient care. Ensuring privacy and the security of health information is a key component to building the trust required to realize the potential benefits of electronic health information exchange. This study was aimed to manage nursing data security in the EHR and also discover the viewpoints of hospital information system vendors (computer companies) and hospital information technology specialists about nursing data security. This research is a cross sectional analytic-descriptive study. The study populations were IT experts at the academic hospitals and computer companies of Tehran city in Iran. Data was collected by a self-developed questionnaire whose validity and reliability were confirmed using the experts' opinions and Cronbach's alpha coefficient respectively. Data was analyzed through Spss Version 18 and by descriptive and analytic statistics. The findings of the study revealed that user name and password were the most important methods to authenticate the nurses, with mean percent of 95% and 80%, respectively, and also the most significant level of information security protection were assigned to administrative and logical controls. There was no significant difference between opinions of both groups studied about the levels of information security protection and security requirements (p>0.05). Moreover the access to servers by authorized people, periodic security update, and the application of authentication and authorization were defined as the most basic security requirements from the viewpoint of more than 88 percent of recently-mentioned participants. Computer companies as system designers and hospitals information technology specialists as systems users and stakeholders present many important views about security requirements for EHR systems and nursing electronic documentation systems. Prioritizing of these requirements helps policy makers to decide what to do when planning for EHR implementation. Therefore, to make appropriate security decisions and to achieve the expected level of protection of the electronic nursing information, it is suggested to consider the priorities of both groups of experts about security principles and also discuss the issues seem to be different between two groups of participants in the research.

Research on the tool holder mode in high speed machining

NASA Astrophysics Data System (ADS)

Zhenyu, Zhao; Yongquan, Zhou; Houming, Zhou; Xiaomei, Xu; Haibin, Xiao

2018-03-01

High speed machining technology can improve the processing efficiency and precision, but also reduce the processing cost. Therefore, the technology is widely regarded in the industry. With the extensive application of high-speed machining technology, high-speed tool system has higher and higher requirements on the tool chuck. At present, in high speed precision machining, several new kinds of clip heads are as long as there are heat shrinkage tool-holder, high-precision spring chuck, hydraulic tool-holder, and the three-rib deformation chuck. Among them, the heat shrinkage tool-holder has the advantages of high precision, high clamping force, high bending rigidity and dynamic balance, etc., which are widely used. Therefore, it is of great significance to research the new requirements of the machining tool system. In order to adapt to the requirement of high speed machining precision machining technology, this paper expounds the common tool holder technology of high precision machining, and proposes how to select correctly tool clamping system in practice. The characteristics and existing problems are analyzed in the tool clamping system.

Material Requirements, Selection And Development for the Proposed JIMO SpacePower System

NASA Astrophysics Data System (ADS)

Ring, P. J.; Sayre, E. D.

2004-02-01

NASA is proposing a major new nuclear Space initiative-The Jupiter Icy Moons Orbiter (JIMO). A mission such as this inevitably requires a significant power source both for propulsion and for on-board power. Three reactor concepts, liquid metal cooled, heat pipe cooled and gas cooled are being considered together with three power conversion systems Brayton (cycle), Thermoelectric and Stirling cycles, and possibly Photo voltaics for future systems. Regardless of the reactor system selected it is almost certain that high temperature (materials), refractory alloys, will be required. This paper revisits the material selection options, reviewing the rationale behind the SP-100 selection of Nb-1Zr as the major cladding and structural material and considers the alternatives and developments needed for the longer duty cycle of the JIMO power supply. A side glance is also taken at the basis behind the selection of Uranium nitride fuel over UO2 or UC and a brief discussion of the reason for the selection of Lithium as the liquid metal coolant for SP-100 over other liquid metals.

In-Situ Propellant Supplied Lunar Lander Concept

NASA Astrophysics Data System (ADS)

Donahue, Benjamin; Maulsby, Curtis

2008-01-01

Future NASA and commercial Lunar missions will require innovative spacecraft configurations incorporating reliable, sustainable propulsion, propellant storage, power and crew life support technologies that can evolve into long duration, partially autonomous systems that can be used to emplace and sustain the massive supplies required for a permanently occupied lunar base. Ambitious surface science missions will require efficient Lunar transfer systems to provide the consumables, science equipment, energy generation systems, habitation systems and crew provisions necessary for lengthy tours on the surface. Lunar lander descent and ascent stages become significantly more efficient when they can be refueled on the Lunar surface and operated numerous times. Landers enabled by Lunar In-Situ Propellant Production (ISPP) facilities will greatly ease constraints on spacecraft mass and payload delivery capability, and may operate much more affordably (in the long term) then landers that are dependant on Earth supplied propellants. In this paper, a Lander concept that leverages ISPP is described and its performance is quantified. Landers, operating as sortie vehicles from Low Lunar Orbit, with efficiencies facilitated by ISPP will enable economical utilization and enhancements that will provide increasingly valuable science yields from Lunar Bases.

High-Efficiency Solar Thermal Vacuum Demonstration Completed for Refractive Secondary Concentrator

NASA Technical Reports Server (NTRS)

Wong, Wayne A.

2001-01-01

Common to many of the space applications that utilize solar thermal energy--such as electric power conversion, thermal propulsion, and furnaces--is a need for highly efficient, solar concentration systems. An effort is underway at the NASA Glenn Research Center to develop the refractive secondary concentrator, which uses refraction and total internal reflection to efficiently concentrate and direct solar energy. When used in combination with advanced lightweight primary concentrators, the refractive secondary concentrator enables very high system concentration ratios (10,000 to 1) and very high temperatures (>2000 K). The innovative refractive secondary concentrator offers significant advantages over all other types of secondary concentrators. The refractive secondary offers the highest throughput efficiency, provides for flux tailoring, requires no active cooling, relaxes the pointing and tracking requirements of the primary concentrator, and enables very high system concentration ratios. This technology has broad applicability to any system that requires the conversion of solar energy to heat. Glenn initiated the development of the refractive secondary concentrator in support of Shooting Star, a solar thermal propulsion flight experiment, and continued the development in support of Space Solar Power.

A survey of advanced battery systems for space applications

NASA Technical Reports Server (NTRS)

Attia, Alan I.

1989-01-01

The results of a survey on advanced secondary battery systems for space applications are presented. The objectives were: to identify advanced battery systems capable of meeting the requirements of various types of space missions, with significant advantages over currently available batteries, to obtain an accurate estimate of the anticipated improvements of these advanced systems, and to obtain a consensus for the selection of systems most likely to yield the desired improvements. Few advanced systems are likely to exceed a specific energy of 150 Wh/kg and meet the additional requirements of safety and reliability within the next 15 years. The few that have this potential are: (1) regenerative fuel cells, both alkaline and solid polymer electrolyte (SPE) types for large power systems; (2) lithium-intercalatable cathodes, particularly the metal ozides intercalatable cathodes (MnO2 or CoO2), with applications limited to small spacecrafts requiring limited cycle life and low power levels; (3) lithium molten salt systems (e.g., LiAl-FeS2); and (4) Na/beta Alumina/Sulfur or metal chlorides cells. Likely technological advances that would enhance the performance of all the above systems are also identified, in particular: improved bifunctional oxygen electrodes; improved manufacturing technology for thin film lithium electrodes in combination with polymeric electrolytes; improved seals for the lithium molten salt cells; and improved ceramics for sodium/solid electrolyte cells.

Human Factors Engineering. A Self-Paced Text, Lessons 36-40,

DTIC Science & Technology

1981-08-01

proposed contract does not involve ’significant human interface for operation/ maintenance /control,’ the selection guide should not be used. Turn to Page 98... work space configuration, packaging, and labeling. These are all aspects of maintenance which need to be incorporated into the original design plans... work done. An ROC is a ’Required Operational Capability’ statement that is required by the Army during the system acquisition process . Return to Page

Significance of User Participation in a Hospital Information System Success: Insights From a Case Study.

PubMed

Saleem, Naveed; Steel, Douglas; Gercek, Gokhan; Chandra, Ashish

User participation in the development of a system is universally prescribed as an effective strategy to ensure the success of the resultant system. However, the existing literature on the merits of user participation only provides equivocal evidence. Various analyses of this literature point out that this equivocal evidence may be due to inconsistent operational measures of the user participation and system success constructs. Planned organizational change and participative decision making, the underlying paradigms of user participation construct, suggest that the development of some information systems may require blending of users' system-related functional expertise and developers' technical expertise to ensure system success. These paradigms also maintain that in case of well-defined, structured information systems user participation should enhance the likelihood of system success through better user understanding of the need for the system and system content and objectives, user trust, and a sense of system ownership. This research also described a case study involving the development and implementation of a medical records system for a neonatal intensive care unit in a large hospital in Texas. The case study provides evidence that in systems that require incorporation of user functional expertise user participation will enhance the likelihood of system success.

The HYDICE instrument design and its application to planetary instruments

NASA Technical Reports Server (NTRS)

Basedow, R.; Silverglate, P.; Rappoport, W.; Rockwell, R.; Rosenberg, D.; Shu, K.; Whittlesey, R.; Zalewski, E.

1993-01-01

The Hyperspectral Digital Imagery Collection Experiment (HYDICE) instrument represents a significant advance in the state of the art in hyperspectral sensors. It combines a higher signal-to-noise ratio (SNR) and significantly better spatial and spectral resolution and radio metric accuracy than systems flying on aircraft today. The need for 'clean' data, i.e., data free of sampling artifacts and excessive spatial or spectral noise, is a key driver behind the difficult combination of performance requirements laid out for HYDICE. Most of these involve the sensor optics and detector. This paper presents an optimized approach to those requirements, one that comprises push broom scanning, a single, mechanically cooled focal plane, a double-pass prism spectrometer, and an easily fabricated yet wide-field telescope. Central to the approach is a detector array that covers the entire spectrum from 0.4 to 2.5 microns. Among the major benefits conferred by such a design are optical and mechanical simplicity, low polarization sensitivity, and coverage of the entire spectrum without suffering the spectral gaps caused by beam splitters. The overall system minimizes interfaces to the C-141 aircraft on which it will be flown, can be calibrated on the ground and in flight to accuracies better than those required, and is designed for simple, push-button operation. Only unprocessed data are recorded during flight. A ground data processing station provides quick-look, calibration correction, and archiving capabilities, with a throughput better than the requirements. Overall performance of the system is expected to provide the solid database required to evaluate the potential of hyperspectral imagery in a wide variety of applications. HYDICE can be regarded as a test bed for future planetary instruments. The ability to spectrally image a wide field of view over multiple spectral octaves offers obvious advantages and is expected to maximize science return for the required cost and weight.

Research on the Application of Risk-based Inspection for the Boiler System in Power Plant

NASA Astrophysics Data System (ADS)

Li, Henan

2017-12-01

Power plant boiler is one of the three main equipment of coal-fired power plants, is very tall to the requirement of the safe and stable operation, in a significant role in the whole system of thermal power generation, a risk-based inspection is a kind of pursuit of security and economy of unified system management idea and method, can effectively evaluate equipment risk and reduce the operational cost.

Engineering Development Program of a Closed Aluminum-Oxygen Semi-cell System for an Unmanned Underwater Vehicle: An Update

NASA Technical Reports Server (NTRS)

Gregg, Dane W.; Hall, Susan E.

1996-01-01

Most emerging unmanned undersea vehicle (UUV) missions require significantly longer range and endurance than is achievable with existing battery technology. The Aluminum-Oxygen (Al-O2) semi-cell is a candidate technology capable of providing a significant improvement in endurance compared to the silver-zinc battery technology currently in use in UUVs and compares favorably to other proposed UUV power systems not only in performance, but also in safety and logistics. An Al-O2 semi-cell system is under development, consisting of a cell stack, gas management, oxygen storage, electrolyte management coolant and controller subsystems. It is designed to replace the existing silver-zinc battery and meet existing weight, volume, electrical and thermal requirements, therefore minimizing modification to the UUV. A detailed system design is complete. A component and material endurance test to evaluate compatibility and reliability of various materials and components is complete. Sub=scale (short stack) system testing is complete. A full-scale demonstration unit is now under construction for testing in the second half of 1995. The full scale demonstration test will simulate environmental conditions of the operational system. This paper summarizes the results of the extensive short stack and endurance test programs, describes the plan for full-scale testing, and concludes with a brief discussion of future directions for this technology.

Re-Assessing Leaching Requirements for the Salinity Control under New Irrigation Regimes

NASA Astrophysics Data System (ADS)

Wu, Laosheng; Yang, Ting; Šimůnek, Jirka

2017-04-01

Irrigation is essential to sustain agricultural production, but it adds dissolved salts (or salinity) to croplands. Leaching is thus necessary to keep the average rootzone salinity below the plant threshold EC levels in order to sustain crop production. Current leaching requirement (LR) calculation is based on steady-state, one-dimensional (1D), and water balance approaches, which often overestimates the LRs under transient field conditions. While in recent years, surface and sprinkler irrigated fields have been largely converted to drip or micro-spray systems and deficit irrigation has become more popular, currently accepted LRs may not be appropriate for these irrigation systems. Under point or line irrigation sources (e.g., drips or drip-lines), water and salts move both downwards and laterally, which may lead to highly saline areas on the edges of the wetted area. Under such circumstances, processes such as precipitation/dissolution of mineral phases and/or cation exchange may significantly affect the leaching requirement. The overall objective of this research was to use computer simulation models (i.e., Hydrus-2D and UnsatChem) to evaluate LRs under transient conditions and new irrigation regimes. Simulations were carried out using parameters for soils, climate zones, and major crops and their corresponding fertilization practices typical for California to: (1) Assess the effects of salt precipitation/dissolution on the leaching requirement (LR); (2) Evaluate localized water movement on average rootzone salinity and the leaching requirement (LR); (3) Evaluate leaching requirements for soils under deficit irrigation; and (4) Assess the effects of rainfall on the leaching requirement. Information from this research could significantly impact water management practices in irrigated croplands.

A Multi-Purpose Modular Electronics Integration Node for Exploration Extravehicular Activity

NASA Technical Reports Server (NTRS)

Hodgson, Edward; Papale, William; Wichowski, Robert; Rosenbush, David; Hawes, Kevin; Stankiewicz, Tom

2013-01-01

As NASA works to develop an effective integrated portable life support system design for exploration Extravehicular activity (EVA), alternatives to the current system s electrical power and control architecture are needed to support new requirements for flexibility, maintainability, reliability, and reduced mass and volume. Experience with the current Extravehicular Mobility Unit (EMU) has demonstrated that the current architecture, based in a central power supply, monitoring and control unit, with dedicated analog wiring harness connections to active components in the system has a significant impact on system packaging and seriously constrains design flexibility in adapting to component obsolescence and changing system needs over time. An alternative architecture based in the use of a digital data bus offers possible wiring harness and system power savings, but risks significant penalties in component complexity and cost. A hybrid architecture that relies on a set of electronic and power interface nodes serving functional models within the Portable Life Support System (PLSS) is proposed to minimize both packaging and component level penalties. A common interface node hardware design can further reduce penalties by reducing the nonrecurring development costs, making miniaturization more practical, maximizing opportunities for maturation and reliability growth, providing enhanced fault tolerance, and providing stable design interfaces for system components and a central control. Adaptation to varying specific module requirements can be achieved with modest changes in firmware code within the module. A preliminary design effort has developed a common set of hardware interface requirements and functional capabilities for such a node based on anticipated modules comprising an exploration PLSS, and a prototype node has been designed assembled, programmed, and tested. One instance of such a node has been adapted to support testing the swingbed carbon dioxide and humidity control element in NASA s advanced PLSS 2.0 test article. This paper will describe the common interface node design concept, results of the prototype development and test effort, and plans for use in NASA PLSS 2.0 integrated tests.

Risk Assessment and Control through Countermeasure System Iplementation for Long-term Crew Exposure to Microgravity

NASA Technical Reports Server (NTRS)

Gernand, Jeremy M.

2004-01-01

Experience with the International Space Station (ISS) program demonstrates the degree to which engineering design and operational solutions must protect crewmembers from health risks due to long-term exposure to the microgravity environment. Risks to safety and health due to degradation in the microgravity environment include crew inability to complete emergency or nominal activities, increased risk of injury, and inability to complete safe return to the ground due to reduced strength or embrittled bones. These risks without controls slowly increase in probability for the length of the mission and become more significant for increasing mission durations. Countermeasures to microgravity include hardware systems that place a crewmember s body under elevated stress to produce an effect similar to daily exposure to gravity. The ISS countermeasure system is predominately composed of customized exercise machines. Historical treatment of microgravity countermeasure systems as medical research experiments unintentionally reduced the foreseen importance and therefore the capability of the systems to function in a long-term operational role. Long-term hazardous effects and steadily increasing operational risks due to non-functional countermeasure equipment require a more rigorous design approach and incorporation of redundancy into seemingly non- mission-critical hardware systems. Variations in the rate of health degradation and responsiveness to countermeasures among the crew population drastically increase the challenge for design requirements development and verification of the appropriate risk control strategy. The long-term nature of the hazards and severe limits on logistical re-supply mass, volume and frequency complicates assessment of hardware availability and verification of an adequate maintenance and sparing plan. Design achievement of medically defined performance requirements by microgravity countermeasure systems and incorporation of adequate failure tolerance significantly reduces these risks. Future implementation of on-site monitoring hardware for critical health parameters such as bone mineral density would allow greater responsiveness, efficiency, and optimized design of the countermeasures system.

Energy requirements in pressure irrigation systems

NASA Astrophysics Data System (ADS)

Sánchez, R.; Rodríguez-Sinobas, L.; Juana, L.; Laguna, F. V.; Castañón, G.; Gil, M.; Benítez, J.

2012-04-01

Modernization of irrigation schemes, generally understood as transformation of surface irrigation systems into pressure -sprinkler and trickle- irrigation systems, aims at, among others, improving irrigation efficiency and reduction of operation and maintenance efforts made by the irrigators. However, pressure irrigation systems, in contrast, carry a serious energy cost. Energy requirements depend on decisions taken on management strategies during the operation phase, which are conditioned by previous decisions taken on the design project of the different elements which compose the irrigation system. Most of the countries where irrigation activity is significant bear in mind that modernization irrigation must play a key role in the agricultural infrastructure policies. The objective of this study is to characterize and estimate the mean and variation of the energy consumed by common types of irrigation systems and their management possibilities. The work includes all processes involved from the diversion of water into irrigation specific infrastructure to water discharge by the emitters installed on the crop fields. Simulation taking into account all elements comprising the irrigation system has been used to estimate the energy requirements of typical irrigation systems of several crop production systems. It has been applied to extensive and intensive crop systems, such us extensive winter crops, summer crops and olive trees, fruit trees and vineyards and intensive horticulture in greenhouses. The simulation of various types of irrigation systems and management strategies, in the framework imposed by particular cropping systems, would help to develop criteria for improving the energy balance in relation to the irrigation water supply productivity.

Health policy and systems research: towards a better understanding and review of ethical issues.

PubMed

Luyckx, Valerie Ann; Biller-Andorno, Nikola; Saxena, Abha; Tran, Nhan T

2017-01-01

Given the focus on health systems in the post-millennium development goal era and moving towards the sustainable development goals, there is a compelling need for a common framework for health policy and systems research ethics to guide researchers and facilitate review by research ethics committees. A consultation of global health policy and systems research and ethics experts was convened to identify ethical considerations relevant to health policy and systems research based on existing knowledge and to identify knowledge gaps through a scoping review and further expert deliberation. Health policy and systems research is highly complex and, in the absence of guidance documents, there is significant variability in ethics review. Although fundamental ethical principles pertain to both traditional clinical research and health policy and systems research, the application of these principles requires a comprehensive understanding of the nature of health policy and systems research with its distinct challenges. Such awareness must be raised among researchers and research ethics committees. Current research ethics committees lack familiarity with health policy and systems research and because health policy and systems research is conducted in real-world contexts, committees often have difficulties in determining whether a project is indeed research and/or requires ethical review. Given the strong current focus on health policy and systems research to rapidly improve health and health systems functioning globally, greater engagement and dialogue around the ethical concerns is required to optimise research review and research conduct in this rapidly evolving field.

Health policy and systems research: towards a better understanding and review of ethical issues

PubMed Central

Biller-Andorno, Nikola; Saxena, Abha; Tran, Nhan T

2017-01-01

Given the focus on health systems in the post-millennium development goal era and moving towards the sustainable development goals, there is a compelling need for a common framework for health policy and systems research ethics to guide researchers and facilitate review by research ethics committees. A consultation of global health policy and systems research and ethics experts was convened to identify ethical considerations relevant to health policy and systems research based on existing knowledge and to identify knowledge gaps through a scoping review and further expert deliberation. Health policy and systems research is highly complex and, in the absence of guidance documents, there is significant variability in ethics review. Although fundamental ethical principles pertain to both traditional clinical research and health policy and systems research, the application of these principles requires a comprehensive understanding of the nature of health policy and systems research with its distinct challenges. Such awareness must be raised among researchers and research ethics committees. Current research ethics committees lack familiarity with health policy and systems research and because health policy and systems research is conducted in real-world contexts, committees often have difficulties in determining whether a project is indeed research and/or requires ethical review. Given the strong current focus on health policy and systems research to rapidly improve health and health systems functioning globally, greater engagement and dialogue around the ethical concerns is required to optimise research review and research conduct in this rapidly evolving field. PMID:29225934

Toward an integrated computerized patient record.

PubMed

Dole, T R; Luberti, A A

2000-04-01

Developing a comprehensive electronic medical record system to serve ambulatory care providers in a large health care enterprise requires significant time and resources. One approach to achieving this system is to devise a series of short-term, workable solutions until a complete system is designed and implemented. The initial solution introduced a basic (mini) medical record system that provided an automated problem/summary sheet and decentralization of ambulatory-based medical records. The next step was to partner with an information system vendor committed to continued development of the long-term system capable of supporting the health care organization well into the future.

Analysis of space systems study for the space disposal of nuclear waste study report. Volume 2: Technical report

NASA Technical Reports Server (NTRS)

1981-01-01

Reasonable space systems concepts were systematically identified and defined and a total system was evaluated for the space disposal of nuclear wastes. Areas studied include space destinations, space transportation options, launch site options payload protection approaches, and payload rescue techniques. Systems level cost and performance trades defined four alternative space systems which deliver payloads to the selected 0.85 AU heliocentric orbit destination at least as economically as the reference system without requiring removal of the protective radiation shield container. No concepts significantly less costly than the reference concept were identified.

Rotary Wing Deceleration Use on Titan

NASA Technical Reports Server (NTRS)

Young, Larry A.; Steiner, Ted J.

2011-01-01

Rotary wing decelerator (RWD) systems were compared against other methods of atmospheric deceleration and were determined to show significant potential for application to a system requiring controlled descent, low-velocity landing, and atmospheric research capability on Titan. Design space exploration and down-selection results in a system with a single rotor utilizing cyclic pitch control. Models were developed for selection of a RWD descent system for use on Titan and to determine the relationships between the key design parameters of such a system and the time of descent. The possibility of extracting power from the system during descent was also investigated.