Reliability issues of free-space communications systems and networks

NASA Astrophysics Data System (ADS)

Willebrand, Heinz A.

2003-04-01

Free space optics (FSO) is a high-speed point-to-point connectivity solution traditionally used in the enterprise campus networking market for building-to-building LAN connectivity. However, more recently some wire line and wireless carriers started to deploy FSO systems in their networks. The requirements on FSO system reliability, meaing both system availability and component reliability, are far more stringent in the carrier market when compared to the requirements in the enterprise market segment. This paper tries to outline some of the aspects that are important to ensure carrier class system reliability.

Intelligent redundant actuation system requirements and preliminary system design

NASA Technical Reports Server (NTRS)

Defeo, P.; Geiger, L. J.; Harris, J.

1985-01-01

Several redundant actuation system configurations were designed and demonstrated to satisfy the stringent operational requirements of advanced flight control systems. However, this has been accomplished largely through brute force hardware redundancy, resulting in significantly increased computational requirements on the flight control computers which perform the failure analysis and reconfiguration management. Modern technology now provides powerful, low-cost microprocessors which are effective in performing failure isolation and configuration management at the local actuator level. One such concept, called an Intelligent Redundant Actuation System (IRAS), significantly reduces the flight control computer requirements and performs the local tasks more comprehensively than previously feasible. The requirements and preliminary design of an experimental laboratory system capable of demonstrating the concept and sufficiently flexible to explore a variety of configurations are discussed.

Environmental Quality: Environmental Protection and Enhancement

DTIC Science & Technology

2002-01-17

have an adverse effect on human health . These regulations are federally enforceable. Primacy states may have more stringent requirements. Primary...includes TT requirements for filtered and unfiltered systems that are specifically designed to protect against the adverse health effects of exposure to...MTBE (20) Alachlor ESA (36) Lead- 210 (9) Nitrobenzene (21) 1,2-diphenylhydrazine (37) Polonium - 210 (10) Terbacil (22) Diazinon (11) Acetochlor (23

40 CFR 35.910-7 - Fiscal Year 1977 Supplemental Appropriations Act allotments.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (secondary treatment, more stringent treatment required to meet water quality standards, and interceptor..., and V (secondary treatment, more stringent treatment required to meet water quality standards... Mexico 3,272,000 New York 105,294,000 North Carolina 20,722,000 North Dakota 3,272,000 Ohio 55,522,000...

40 CFR 142.10 - Requirements for a determination of primary enforcement responsibility.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS... enforcement responsibility. A State has primary enforcement responsibility for public water systems in the...: (a) Has adopted drinking water regulations which are no less stringent than the national primary...

40 CFR 142.10 - Requirements for a determination of primary enforcement responsibility.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS... enforcement responsibility. A State has primary enforcement responsibility for public water systems in the...: (a) Has adopted drinking water regulations which are no less stringent than the national primary...

40 CFR 142.10 - Requirements for a determination of primary enforcement responsibility.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS... enforcement responsibility. A State has primary enforcement responsibility for public water systems in the...: (a) Has adopted drinking water regulations which are no less stringent than the national primary...

Orphan Toxin OrtT (YdcX) of Escherichia coli Reduces Growth during the Stringent Response

DTIC Science & Technology

2015-01-29

antimicrobials trimethoprim and sulfamethoxazole; these antimicrobials induce the stringent response by inhibiting tetrahydrofolate synthesis...in the presence of both antimicrobials trimethoprim and sulfamethoxazole; these antimicrobials induce the stringent response by inhibiting...level [20]. Toxins 2015, 7 301 Despite these difficulties in determining physiological roles, TA systems are clearly phage inhibition systems

Manufacturing considerations for AMLCD cockpit displays

NASA Astrophysics Data System (ADS)

Luo, Fang-Chen

1995-06-01

AMLCD cockpit displays need to meet more stringent requirements compared with AMLCD commercial displays in areas such as environmental conditions, optical performance and device reliability. Special considerations are required for the manufacturing of AMLCD cockpit displays in each process step to address these issues. Some examples are: UV stable polarizers, wide-temperature LC material, strong LC glue seal, ESS test system, gray scale voltage EEPROM, etc.

DSN radio science system design and testing for Voyager-Neptune encounter

NASA Technical Reports Server (NTRS)

Ham, N. C.; Rebold, T. A.; Weese, J. F.

1989-01-01

The Deep Space Network (DSN) Radio Science System presently implemented within the Deep Space Network was designed to meet stringent requirements imposed by the demands of the Voyager-Neptune encounter and future missions. One of the initial parameters related to frequency stability is discussed. The requirement, specification, design, and methodology for measuring this parameter are described. A description of special instrumentation that was developed for the test measurements and initial test data resulting from the system tests performed at Canberra, Australia and Usuda, Japan are given.

Direct digital RF synthesis and modulation for MSAT mobile applications

NASA Technical Reports Server (NTRS)

Crozier, Stewart; Datta, Ravi; Sydor, John

1993-01-01

A practical method of performing direct digital RF synthesis using the Hilbert transform single sideband (SSB) technique is described. It is also shown that amplitude and phase modulation can be achieved directly at L-band with frequency stability and spurii performance exceeding stringent MSAT system requirements.

Opportunities for improving risk communication during the permitting process for entomophagous biological control agents: A review of current systems

USDA-ARS?s Scientific Manuscript database

Concerns about potentially irreversible non-target impacts from the importation and release of entomophagous biological control agents (BCAs) have resulted in increasingly stringent import requirements by National Plant Protection Organizations. Despite numerous scientific publications on the poten...

Modular Wireless Data-Acquisition and Control System

NASA Technical Reports Server (NTRS)

Perotti, Jose; Lucena, Angel; Medelius, Pedro; Mata, Carlos; Eckhoff, Anthony; Blalock, Norman

2004-01-01

A modular wireless data-acquisition and control system, now in operation at Kennedy Space Center, offers high performance at relatively low cost. The system includes a central station and a finite number of remote stations that communicate with each other through low-power radio frequency (RF) links. Designed to satisfy stringent requirements for reliability, integrity of data, and low power consumption, this system could be reproduced and adapted to use in a broad range of settings.

Supporting scalability and flexibility in a distributed management platform

NASA Astrophysics Data System (ADS)

Jardin, P.

1996-06-01

The TeMIP management platform was developed to manage very large distributed systems such as telecommunications networks. The management of these networks imposes a number of fairly stringent requirements including the partitioning of the network, division of work based on skills and target system types and the ability to adjust the functions to specific operational requirements. This requires the ability to cluster managed resources into domains that are totally defined at runtime based on operator policies. This paper addresses some of the issues that must be addressed in order to add a dynamic dimension to a management solution.

Downsizing Antenna Technologies for Mobile and Satellite Communications

NASA Technical Reports Server (NTRS)

Huang, J.; Densmore, A.; Tulintseff, A.; Jamnejad, V.

1993-01-01

Due to the increasing and stringent functional requirements (larger capacity, longer distances, etc.) of modern day communication systems, higher antenna gains are generally needed. This higher gain implies larger antenna size and mass which are undesirable to many systems. Consequently, downsizing antenna technology becomes one of the most critical areas for research and development efforts. Techniques to reduce antenna size can be categorized and are briefly discussed.

Polymeric additive performance in closed whitewater systems

Treesearch

T. H. Wegner

1984-01-01

“With more stringent requirements on discharge water quality and with escalating water treatment costs, water recycling within the paper mill is of growing importance. A serious problem resulting from more white-water recycling is reduced drainage and fiber or fines retention because of diminished polymeric additive performance. To provide better insight for overcoming...

Cybersecurity Education: Bridging the Gap between Hardware and Software Domains

ERIC Educational Resources Information Center

Lukowiak, Marcin; Radziszowski, Stanislaw; Vallino, James; Wood, Christopher

2014-01-01

With the continuous growth of cyberinfrastructure throughout modern society, the need for secure computing and communication is more important than ever before. As a result, there is also an increasing need for entry-level developers who are capable of designing and building practical solutions for systems with stringent security requirements.…

An Ada implementation of the network manager for the advanced information processing system

NASA Technical Reports Server (NTRS)

Nagle, Gail A.

1986-01-01

From an implementation standpoint, the Ada language provided many features which facilitated the data and procedure abstraction process. The language supported a design which was dynamically flexible (despite strong typing), modular, and self-documenting. Adequate training of programmers requires access to an efficient compiler which supports full Ada. When the performance issues for real time processing are finally addressed by more stringent requirements for tasking features and the development of efficient run-time environments for embedded systems, the full power of the language will be realized.

Toward a workable biosafety system for regulating genetically modified organisms in Ethiopia: balancing conservation and competitiveness.

PubMed

Abraham, Adane

2013-01-01

On September 9, 2009, Ethiopia enacted a highly restrictive biosafety law firmly based on precautionary principles as a foundation for its GMO regulation system. Its drafting process, led by the country's Environmental Protection Authority, was judged as biased, focusing only on protecting the environment from perceived risks, giving little attention to potential benefits of GMOs. Many of its provisions are very stringent, exceeding those of Cartagena Protocol on Biosafety, while others cannot be fulfilled by applicants, collectively rendering the emerged biosafety system unworkable. These provisions include requirements for advance informed agreement and rigorous socioeconomic assessment in risk evaluation for all GMO transactions, including contained research use-which requires the head of the competent national authority of the exporting country to take full responsibility for GMO-related information provided-and stringent labeling, insurance and monitoring requirements for all GMO activities. Furthermore, there is no provision to establish an independent national biosafety decision-making body(ies). As a result, foreign technology owners that provide highly demanded technologies like Bt cotton declined to work with Ethiopia. There is a fear that the emerged biosafety system might also continue to suppress domestic genetic engineering research and development. Thus, to benefit from GMOs, Ethiopia has to revise its biosafety system, primarily by making changes to some provisions of the law in a way that balances its diverse interests of conserving biodiversity, protecting the environment and enhancing competition in agricultural and other economic sectors.

Calibration of the SNO+ experiment

NASA Astrophysics Data System (ADS)

Maneira, J.; Falk, E.; Leming, E.; Peeters, S.; SNO+ Collaboration.

2017-09-01

The main goal of the SNO+ experiment is to perform a low-background and high-isotope-mass search for neutrinoless double-beta decay, employing 780 tonnes of liquid scintillator loaded with tellurium, in its initial phase at 0.5% by mass for a total mass of 1330 kg of 130Te. The SNO+ physics program includes also measurements of geo- and reactor neutrinos, supernova and solar neutrinos. Calibrations are an essential component of the SNO+ data-taking and analysis plan. The achievement of the physics goals requires both an extensive and regular calibration. This serves several goals: the measurement of several detector parameters, the validation of the simulation model and the constraint of systematic uncertainties on the reconstruction and particle identification algorithms. SNO+ faces stringent radiopurity requirements which, in turn, largely determine the materials selection, sealing and overall design of both the sources and deployment systems. In fact, to avoid frequent access to the inner volume of the detector, several permanent optical calibration systems have been developed and installed outside that volume. At the same time, the calibration source internal deployment system was re-designed as a fully sealed system, with more stringent material selection, but following the same working principle as the system used in SNO. This poster described the overall SNO+ calibration strategy, discussed the several new and innovative sources, both optical and radioactive, and covered the developments on source deployment systems.

"Reliability Of Fiber Optic Lans"

NASA Astrophysics Data System (ADS)

Code n, Michael; Scholl, Frederick; Hatfield, W. Bryan

1987-02-01

Fiber optic Local Area Network Systems are being used to interconnect increasing numbers of nodes. These nodes may include office computer peripherals and terminals, PBX switches, process control equipment and sensors, automated machine tools and robots, and military telemetry and communications equipment. The extensive shared base of capital resources in each system requires that the fiber optic LAN meet stringent reliability and maintainability requirements. These requirements are met by proper system design and by suitable manufacturing and quality procedures at all levels of a vertically integrated manufacturing operation. We will describe the reliability and maintainability of Codenoll's passive star based systems. These include LAN systems compatible with Ethernet (IEEE 802.3) and MAP (IEEE 802.4), and software compatible with IBM Token Ring (IEEE 802.5). No single point of failure exists in this system architecture.

Characteristic analysis and simulation for polysilicon comb micro-accelerometer

NASA Astrophysics Data System (ADS)

Liu, Fengli; Hao, Yongping

2008-10-01

High force update rate is a key factor for achieving high performance haptic rendering, which imposes a stringent real time requirement upon the execution environment of the haptic system. This requirement confines the haptic system to simplified environment for reducing the computation cost of haptic rendering algorithms. In this paper, we present a novel "hyper-threading" architecture consisting of several threads for haptic rendering. The high force update rate is achieved with relatively large computation time interval for each haptic loop. The proposed method was testified and proved to be effective with experiments on virtual wall prototype haptic system via Delta Haptic Device.

Pointing and tracking space mechanism for laser communication

NASA Technical Reports Server (NTRS)

Brunschvig, A.; Deboisanger, M.

1994-01-01

Space optical communication is considered a promising technology regarding its high data rate and confidentiality capabilities. However, it requires today complex satellite systems involving highly accurate mechanisms. This paper aims to highlight the stringent requirements which had to be fulfilled for such a mechanism, the way an existing design has been adapted to meet these requirements, and the main technical difficulties which have been overcome thanks to extensive development tests throughout the C/D phase initiated in 1991. The expected on-orbit performance of this mechanism is also presented.

Contamination control program for the Cosmic Background Explorer

NASA Technical Reports Server (NTRS)

Barney, Richard D.

1991-01-01

Each of the three state of the art instruments flown aboard NASA's Cosmic Background Explorer (COBE) were designed, fabricated, and integrated using unique contamination control procedures to ensure accurate characterization of the diffuse radiation in the universe. The most stringent surface level cleanliness specifications ever attempted by NASA were required by the Diffuse Infrared Background Experiment (DRIBE) which is located inside a liquid helium cooled dewar along with the Far Infrared Absolute Spectrophotometer (FIRAS). The DRIBE instrument required complex stray radiation suppression that defined a cold primary optical baffle system surface cleanliness level of 100A. The cleanliness levels of the cryogenic FIRAS instrument and the Differential Microwave Radiometer (DMR) which were positioned symmetrically around the dewar were less stringent ranging from 300 to 500A. To achieve these instrument cleanliness levels, the entire flight spacecraft was maintained at level 500A throughout each phase of development. The COBE contamination control program is described along with the difficulties experienced in maintaining the cleanliness quality of personnel and flight hardware throughout instrument assembly.

Tilt-tuned etalon locking for tunable laser stabilization.

PubMed

Gibson, Bradley M; McCall, Benjamin J

2015-06-15

Locking to a fringe of a tilt-tuned etalon provides a simple, inexpensive method for stabilizing tunable lasers. Here, we describe the use of such a system to stabilize an external-cavity quantum cascade laser; the locked laser has an Allan deviation of approximately 1 MHz over a one-second integration period, and has a single-scan tuning range of approximately 0.4  cm(-1). The system is robust, with minimal alignment requirements and automated lock acquisition, and can be easily adapted to different wavelength regions or more stringent stability requirements with minor alterations.

Circuitry Linking the Csr and Stringent Response Global Regulatory Systems

PubMed Central

Edwards, Adrianne N.; Patterson-Fortin, Laura M.; Vakulskas, Christopher A.; Mercante, Jeffrey W.; Potrykus, Katarzyna; Vinella, Daniel; Camacho, Martha I.; Fields, Joshua A.; Thompson, Stuart A.; Georgellis, Dimitris; Cashel, Michael; Babitzke, Paul; Romeo, Tony

2011-01-01

Summary CsrA protein regulates important cellular processes by binding to target mRNAs and altering their translation and/or stability. In Escherichia coli, CsrA binds to sRNAs, CsrB and CsrC, which sequester CsrA and antagonize its activity. Here, mRNAs for relA, spoT and dksA of the stringent response system were found among 721 different transcripts that copurified with CsrA. Many of the transcripts that copurified with CsrA were previously determined to respond to ppGpp and/or DksA. We examined multiple regulatory interactions between the Csr and stringent response systems. Most importantly, DksA and ppGpp robustly activated csrB/C transcription (10-fold), while they modestly activated csrA expression. We propose that CsrA-mediated regulation is relieved during the stringent response. Gel shift assays confirmed high affinity binding of CsrA to relA mRNA leader and weaker interactions with dksA and spoT. Reporter fusions, qRT-PCR, and immunoblotting showed that CsrA repressed relA expression, and (p)ppGpp accumulation during stringent response was enhanced in a csrA mutant. CsrA had modest to negligible effects on dksA and spoT expression. Transcription of dksA was negatively autoregulated via a feedback loop that tended to mask CsrA effects. We propose that the Csr system fine-tunes the stringent response and discuss biological implications of the composite circuitry. PMID:21488981

Regulation of early mRNA synthesis after bacteriophage T4 infection of Escherichia coli.

PubMed Central

Linder, C H; Fast, R

1975-01-01

Regulation of T4-specific mRNA synthesis was studied during leucine starvation of a leucine-requiring stringent Escherichia coli B strain. This was done by imposing starvation prior to T4 infection and then letting RNA synthesis proceed for different time periods. Rifampin or streptolydigin was added to stop further RNA synthesis, and protein synthesis was restored by addition of leucine. Samples were withdrawn at different times, and the enzyme-forming capacities found that, during conditions which elicit the stringent response in uninfected bacteria, immediate early mRNA is not stringently regulated. This conclusion contradicts the earlier conclusion of others, obtained by measuring incorporation of radioactive uracil; this is explained by the observation of Edlin and Neuhard (1967), confirmed and extended by us to the T4-infected cell, that the incorporation of uracil into RNA of a stringent strain is virtually blocked by amino acid starvation, whereas that of adenine continues at 30 to 50% of the rate seen in the presence of the required amino acid. PMID:1099229

Attitude control of an orbiting space vehicle.

NASA Technical Reports Server (NTRS)

Sutherlin, D. W.; Boland, J. S. , III; Borelli, M. T.

1971-01-01

Study of the normal and clamped modes of operation and dynamic response characteristics of the gimbaled control moment gyro (CMG) designed to fulfill the stringent pointing requirements of the Skylab telescope mount when the spacecraft is under the influence of both external and internal torques. The results indicate that the clamped mode of operation provides a feasible approach for significantly improving the system characteristics.

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.

Ultra-low mass drift chambers

NASA Astrophysics Data System (ADS)

Assiro, R.; Cappelli, L.; Cascella, M.; De Lorenzis, L.; Grancagnolo, F.; Ignatov, F.; L'Erario, A.; Maffezzoli, A.; Miccoli, A.; Onorato, G.; Perillo, M.; Piacentino, G.; Rella, S.; Rossetti, F.; Spedicato, M.; Tassielli, G.; Zavarise, G.

2013-08-01

We present a novel low mass drift chamber concept, developed in order to fulfill the stringent requirements imposed by the experiments for extremely rare processes, which require high resolutions (order of 100-200 keV/c) for particle momenta in a range (50-100 MeV/c) totally dominated by the multiple scattering contribution. We describe a geometry optimization procedure and a new wiring strategy with a feed-through-less wire anchoring system developed and tested on a drift chamber prototype under completion at INFN-Lecce .

Testing Cobol Programs by Mutation. Volume II. CMS 1 System Documentation,

DTIC Science & Technology

1980-02-01

8217 LOOP MVth a’ solution was to enebese the macn depesi- 1F rumen Tom dent imes ide a apeelal type of mdulo called a G aaraadom(2); device maul* (see...software status register can be modified at will, while the required, but as an additional benefit, Modula contents of the buffer can be dealt with as...language. The requirements are stringent and usu- Dick up the contents of the address by Indirect ally the work Is never completed, an the uses for

NASA's Solar Dynamics Observatory (SDO): A Systems Approach to a Complex Mission

NASA Technical Reports Server (NTRS)

Ruffa, John A.; Ward, David K.; Bartusek, LIsa M.; Bay, Michael; Gonzales, Peter J.; Pesnell, William D.

2012-01-01

The Solar Dynamics Observatory (SDO) includes three advanced instruments, massive science data volume, stringent science data completeness requirements, and a custom ground station to meet mission demands. The strict instrument science requirements imposed a number of challenging drivers on the overall mission system design, leading the SDO team to adopt an integrated systems engineering presence across all aspects of the mission to ensure that mission science requirements would be met. Key strategies were devised to address these system level drivers and mitigate identified threats to mission success. The global systems engineering team approach ensured that key drivers and risk areas were rigorously addressed through all phases of the mission, leading to the successful SDO launch and on-orbit operation. Since launch, SDO's on-orbit performance has met all mission science requirements and enabled groundbreaking science observations, expanding our understanding of the Sun and its dynamic processes.

NASA's Solar Dynamics Observatory (SDO): A Systems Approach to a Complex Mission

NASA Technical Reports Server (NTRS)

Ruffa, John A.; Ward, David K.; Bartusek, Lisa M.; Bay, Michael; Gonzales, Peter J.; Pesnell, William D.

2012-01-01

The Solar Dynamics Observatory (SDO) includes three advanced instruments, massive science data volume, stringent science data completeness requirements, and a custom ground station to meet mission demands. The strict instrument science requirements imposed a number of challenging drivers on the overall mission system design, leading the SDO team to adopt an integrated systems engineering presence across all aspects of the mission to ensure that mission science requirements would be met. Key strategies were devised to address these system level drivers and mitigate identified threats to mission success. The global systems engineering team approach ensured that key drivers and risk areas were rigorously addressed through all phases of the mission, leading to the successful SDO launch and on-orbit operation. Since launch, SDO s on-orbit performance has met all mission science requirements and enabled groundbreaking science observations, expanding our understanding of the Sun and its dynamic processes.

Model predictive control of a lean-burn gasoline engine coupled with a passive selective catalytic reduction system

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

Chen, Pingen; Lin, Qinghua; Prikhodko, Vitaly Y.

Lean-burn gasoline engines have demonstrated 10–20% engine efficiency gain over stoichiometric engines and are widely considered as a promising technology for meeting the 54.5 miles-per-gallon (mpg) Corporate Average Fuel Economy standard by 2025. Nevertheless, NOx emissions control for lean-burn gasoline for meeting the stringent EPA Tier 3 emission standards has been one of the main challenges towards the commercialization of highly-efficient lean-burn gasoline engines in the United States. Passive selective catalytic reduction (SCR) systems, which consist of a three-way catalyst and SCR, have demonstrated great potentials of effectively reducing NOx emissions for lean gasoline engines but may cause significant fuelmore » penalty due to ammonia generation via rich engine combustion. The purpose of this study is to develop a model-predictive control (MPC) scheme for a lean-burn gasoline engine coupled with a passive SCR system to minimize the fuel penalty associated with passive SCR operation while satisfying stringent NOx and NH3 emissions requirements. Simulation results demonstrate that the MPC-based control can reduce the fuel penalty by 47.7% in a simulated US06 cycle and 32.0% in a simulated UDDS cycle, compared to the baseline control, while achieving over 96% deNOx efficiency and less than 15 ppm tailpipe ammonia slip. The proposed MPC control can potentially enable high engine efficiency gain for highly-efficient lean-burn gasoline engine while meeting the stringent EPA Tier 3 emission standards.« less

Circuitry linking the Csr and stringent response global regulatory systems.

PubMed

Edwards, Adrianne N; Patterson-Fortin, Laura M; Vakulskas, Christopher A; Mercante, Jeffrey W; Potrykus, Katarzyna; Vinella, Daniel; Camacho, Martha I; Fields, Joshua A; Thompson, Stuart A; Georgellis, Dimitris; Cashel, Michael; Babitzke, Paul; Romeo, Tony

2011-06-01

CsrA protein regulates important cellular processes by binding to target mRNAs and altering their translation and/or stability. In Escherichia coli, CsrA binds to sRNAs, CsrB and CsrC, which sequester CsrA and antagonize its activity. Here, mRNAs for relA, spoT and dksA of the stringent response system were found among 721 different transcripts that copurified with CsrA. Many of the transcripts that copurified with CsrA were previously determined to respond to ppGpp and/or DksA. We examined multiple regulatory interactions between the Csr and stringent response systems. Most importantly, DksA and ppGpp robustly activated csrB/C transcription (10-fold), while they modestly activated csrA expression. We propose that CsrA-mediated regulation is relieved during the stringent response. Gel shift assays confirmed high affinity binding of CsrA to relA mRNA leader and weaker interactions with dksA and spoT. Reporter fusions, qRT-PCR and immunoblotting showed that CsrA repressed relA expression, and (p)ppGpp accumulation during stringent response was enhanced in a csrA mutant. CsrA had modest to negligible effects on dksA and spoT expression. Transcription of dksA was negatively autoregulated via a feedback loop that tended to mask CsrA effects. We propose that the Csr system fine-tunes the stringent response and discuss biological implications of the composite circuitry. © Published 2011. This article is a US Government work and is in the public domain in the USA.

Advanced Turbo-Charging Research and Development

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

None

2008-02-27

The objective of this project is to conduct analysis, design, procurement and test of a high pressure ratio, wide flow range, and high EGR system with two stages of turbocharging. The system needs to meet the stringent 2010MY emissions regulations at 20% + better fuel economy than its nearest gasoline competitor while allowing equivalent vehicle launch characteristics and higher torque capability than its nearest gasoline competitor. The system will also need to meet light truck/ SUV life requirements, which will require validation or development of components traditionally used only in passenger car applications. The conceived system is termed 'seriessequential turbocharger'more » because the turbocharger system operates in series at appropriate times and also sequentially when required. This is accomplished using intelligent design and control of flow passages and valves. Components of the seriessequential system will also be applicable to parallel-sequential systems which are also expected to be in use for future light truck/SUV applications.« less

Comparison of scientific and administrative database management systems

NASA Technical Reports Server (NTRS)

Stoltzfus, J. C.

1983-01-01

Some characteristics found to be different for scientific and administrative data bases are identified and some of the corresponding generic requirements for data base management systems (DBMS) are discussed. The requirements discussed are especially stringent for either the scientific or administrative data bases. For some, no commercial DBMS is fully satisfactory, and the data base designer must invent a suitable approach. For others, commercial systems are available with elegant solutions, and a wrong choice would mean an expensive work-around to provide the missing features. It is concluded that selection of a DBMS must be based on the requirements for the information system. There is no unique distinction between scientific and administrative data bases or DBMS. The distinction comes from the logical structure of the data, and understanding the data and their relationships is the key to defining the requirements and selecting an appropriate DBMS for a given set of applications.

A Scheduling Algorithm for Replicated Real-Time Tasks

NASA Technical Reports Server (NTRS)

Yu, Albert C.; Lin, Kwei-Jay

1991-01-01

We present an algorithm for scheduling real-time periodic tasks on a multiprocessor system under fault-tolerant requirement. Our approach incorporates both the redundancy and masking technique and the imprecise computation model. Since the tasks in hard real-time systems have stringent timing constraints, the redundancy and masking technique are more appropriate than the rollback techniques which usually require extra time for error recovery. The imprecise computation model provides flexible functionality by trading off the quality of the result produced by a task with the amount of processing time required to produce it. It therefore permits the performance of a real-time system to degrade gracefully. We evaluate the algorithm by stochastic analysis and Monte Carlo simulations. The results show that the algorithm is resilient under hardware failures.

Guanosine 3'-diphosphate 5'-diphosphate is not required for growth rate-dependent control of rRNA synthesis in Escherichia coli.

PubMed Central

Gaal, T; Gourse, R L

1990-01-01

rRNA synthesis in Escherichia coli is subject to at least two regulation systems, growth rate-dependent control and stringent control. The inverse correlation between rRNA synthesis rates and guanosine 3'-diphosphate 5'-diphosphate (ppGpp) levels under various physiological conditions has led to the supposition that ppGpp is the mediator of both control mechanisms by inhibiting transcription from rrn P1 promoters. Recently, relA- spoT- strains have been constructed in which both ppGpp synthesis pathways most likely have been removed (M. Cashel, personal communication). We have confirmed that such strains produce no detectable ppGpp and therefore offer a direct means for testing the involvement of ppGpp in the regulation of rRNA synthesis in vivo. Stringent control was determined by measurement of rRNA synthesis after amino acid starvation, while growth rate control was determined by measurement of rRNA synthesis under different nutritional conditions. As expected, the relA- spoT- strain is relaxed for stringent control. However, growth rate-dependent regulation is unimpaired. These results indicate that growth rate regulation can occur in the absence of ppGpp and imply that ppGpp is not the mediator, or at least is not the sole mediator, of growth rate-dependent control. Therefore, growth rate-dependent control and stringent control may utilize different mechanisms for regulating stable RNA synthesis. PMID:2196571

Conceptual design of a coherent optical system of modular imaging collectors (COSMIC). [telescope array deployed by space shuttle in 1990's

NASA Technical Reports Server (NTRS)

Nein, M. E.; Davis, B. G.

1982-01-01

The Coherent Optical System of Modular Imaging Collectors (COSMIC) is the design concept for a phase-coherent optical telescope array that may be placed in earth orbit by the Space Shuttle in the 1990s. The initial system module is a minimum redundancy array whose photon collecting area is three times larger than that of the Space Telescope, and possesses a one-dimensional resoution of better than 0.01 arcsec in the visible range. Thermal structural requirements are assessed. Although the coherent beam combination requirements will be met by an active control system, the COSMIC structural/thermal design must meet more stringent performance criteria than even those of the Space Telescope.

Mask etcher data strategy for 45nm and beyond

NASA Astrophysics Data System (ADS)

Lewington, Richard; Ibrahim, Ibrahim M.; Panayil, Sheeba; Kumar, Ajay; Yamartino, John

2006-05-01

Mask Etching for the 45nm technology node and beyond requires a system-level data and diagnostics strategy. This necessity stems from the need to control the performance of the mask etcher to increasingly stringent and diverse requirements of the mask production environment. Increasing mask costs and the capability to acquire and consolidate a wealth of data within the mask etch platform are primary motivators towards harnessing data mines for feedback into the mask etching optimization. There are offline and real-time possibilities and scenarios. Here, we discuss the data architecture, acquisition, and strategies of the Applied Materials Tetra II TM Mask Etch System.

Advanced Space-Based Detector Research at the Air Force Research Laboratory

DTIC Science & Technology

2009-03-04

purposes. The dark backgrounds place very stringent requirements on the noise characteristics of the sensor system, resulting in FPAs that must be...signal within a single pixel of a detector. 2. Optical signal amplification 2.1. Quantum interference Quantum well infrared photodetectors ( QWIPs ) are...are now extremely attractive for a growing number of sensor applications. Although considerable progress has been made in QWIPs , their relatively low

Advanced Space-Based Detector Research at the Air Force Research Laboratory (PREPRINT)

DTIC Science & Technology

2006-10-01

purposes. The dark backgrounds place very stringent requirements on the noise characteristics of the sensor system, resulting in FPAs that must be cooled...2.1. Quantum interference Quantum well infrared photodetectors ( QWIPs ) are based on intersubband absorption in III–V semiconductor multi-quantum well...Although considerable progress has been made in QWIPs , their relatively low quantum efficiencies constitute their greatest problem for space-based

Picometer-resolution dual-comb spectroscopy with a free-running fiber laser.

PubMed

Zhao, Xin; Hu, Guoqing; Zhao, Bofeng; Li, Cui; Pan, Yingling; Liu, Ya; Yasui, Takeshi; Zheng, Zheng

2016-09-19

Dual-comb spectroscopy holds the promise as real-time, high-resolution spectroscopy tools. However, in its conventional schemes, the stringent requirement on the coherence between two lasers requires sophisticated control systems. By replacing control electronics with an all-optical dual-comb lasing scheme, a simplified dual-comb spectroscopy scheme is demonstrated using one dual-wavelength, passively mode-locked fiber laser. Pulses with a intracavity-dispersion-determined repetition-frequency difference are shown to have good mutual coherence and stability. Capability to resolve the comb teeth and a picometer-wide optical spectral resolution are demonstrated using a simple data acquisition system. Energy-efficient, free-running fiber lasers with a small comb-tooth-spacing could enable low-cost dual-comb systems.

Considerations in development of expert systems for real-time space applications

NASA Technical Reports Server (NTRS)

Murugesan, S.

1988-01-01

Over the years, demand on space systems has increased tremendously and this trend will continue for the near future. Enhanced capabilities of space systems, however, can only be met with increased complexity and sophistication of onboard and ground systems. Artificial Intelligence and expert system techniques have great potential in space applications. Expert systems could facilitate autonomous decision making, improve in-orbit fault diagnosis and repair, enhance performance and reduce reliance on ground support. However, real-time expert systems, unlike conventional off-line consultative systems, have to satisfy certain special stringent requirements before they could be used for onboard space applications. Challenging and interesting new environments are faced while developing expert system space applications. This paper discusses the special characteristics, requirements and typical life cycle issues for onboard expert systems. Further, it also describes considerations in design, development, and implementation which are particularly important to real-time expert systems for space applications.

Precision Adjustable Liquid Regulator (ALR)

NASA Astrophysics Data System (ADS)

Meinhold, R.; Parker, M.

2004-10-01

A passive mechanical regulator has been developed for the control of fuel or oxidizer flow to a 450N class bipropellant engine for use on commercial and interplanetary spacecraft. There are several potential benefits to the propulsion system, depending on mission requirements and spacecraft design. This system design enables more precise control of main engine mixture ratio and inlet pressure, and simplifies the pressurization system by transferring the function of main engine flow rate control from the pressurization/propellant tank assemblies, to a single component, the ALR. This design can also reduce the thermal control requirements on the propellant tanks, avoid costly Qualification testing of biprop engines for missions with more stringent requirements, and reduce the overall propulsion system mass and power usage. In order to realize these benefits, the ALR must meet stringent design requirements. The main advantage of this regulator over other units available in the market is that it can regulate about its nominal set point to within +/-0.85%, and change its regulation set point in flight +/-4% about that nominal point. The set point change is handled actively via a stepper motor driven actuator, which converts rotary into linear motion to affect the spring preload acting on the regulator. Once adjusted to a particular set point, the actuator remains in its final position unpowered, and the regulator passively maintains outlet pressure. The very precise outlet regulation pressure is possible due to new technology developed by Moog, Inc. which reduces typical regulator mechanical hysteresis to near zero. The ALR requirements specified an outlet pressure set point range from 225 to 255 psi, and equivalent water flow rates required were in the 0.17 lb/sec range. The regulation output pressure is maintained at +/-2 psi about the set point from a P (delta or differential pressure) of 20 to over 100 psid. Maximum upstream system pressure was specified at 320 psi. The regulator is fault tolerant in that it was purposely designed with no shutoff capability, such that the minimum flow position of the poppet still allows the subsystem to provide adequate flow to the main engine for basic operation.

Current Technology for Thermal Protection Systems

NASA Technical Reports Server (NTRS)

Scotti, Stephen J. (Compiler)

1992-01-01

Interest in thermal protection systems for high-speed vehicles is increasing because of the stringent requirements of such new projects as the Space Exploration Initiative, the National Aero-Space Plane, and the High-Speed Civil Transport, as well as the needs for improved capabilities in existing thermal protection systems in the Space Shuttle and in turbojet engines. This selection of 13 papers from NASA and industry summarizes the history and operational experience of thermal protection systems utilized in the national space program to date, and also covers recent development efforts in thermal insulation, refractory materials and coatings, actively cooled structures, and two-phase thermal control systems.

Robust Fixed-Structure Controller Synthesis

NASA Technical Reports Server (NTRS)

Corrado, Joseph R.; Haddad, Wassim M.; Gupta, Kajal (Technical Monitor)

2000-01-01

The ability to develop an integrated control system design methodology for robust high performance controllers satisfying multiple design criteria and real world hardware constraints constitutes a challenging task. The increasingly stringent performance specifications required for controlling such systems necessitates a trade-off between controller complexity and robustness. The principle challenge of the minimal complexity robust control design is to arrive at a tractable control design formulation in spite of the extreme complexity of such systems. Hence, design of minimal complexitY robust controllers for systems in the face of modeling errors has been a major preoccupation of system and control theorists and practitioners for the past several decades.

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.

Creating an optical spectroscopy system for use in a primary care clinical setting (Conference Presentation)

NASA Astrophysics Data System (ADS)

Eshein, Adam; Nguyen, The-Quyen; Radosevich, Andrew J.; Gould, Bradley; Wu, Wenli; Konda, Vani; Yang, Leslie W.; Koons, Ann; Feder, Seth; Valuckaite, Vesta; Roy, Hemant K.; Backman, Vadim

2016-03-01

While there are a plethora of in-vivo spectroscopic techniques that have demonstrated the ability to detect a number of diseases in research trials, very few techniques have successfully become a fully realized clinical technology. This is primarily due to the stringent demands on a clinical device for widespread implementation. Some of these demands include: simple operation requiring minimal or no training, safe for in-vivo patient use, no disruption to normal clinic workflow, tracking of system performance, warning for measurement abnormality, and meeting all FDA guidelines for medical use. Previously, our group developed a fiber optic probe-based optical sensing technique known as low-coherence enhanced backscattering spectroscopy (LEBS) to quantify tissue ultrastructure in-vivo. Now we have developed this technique for the application of prescreening patients for colonoscopy in a primary care (PC) clinical setting. To meet the stringent requirements for a viable medical device used in a PC clinical setting, we developed several novel components including an automated calibration tool, optical contact sensor for signal acquisition, and a contamination sensor to identify measurements which have been affected by debris. The end result is a state-of-the-art medical device that can be realistically used by a PC physician to assess a person's risk for harboring colorectal precancerous lesions. The pilot study of this system shows great promise with excellent stability and accuracy in identifying high-risk patients. While this system has been designed and optimized for our specific application, the system and design concepts are universal to most in-vivo fiber optic based spectroscopic techniques.

Design and Error Analysis of a Vehicular AR System with Auto-Harmonization.

PubMed

Foxlin, Eric; Calloway, Thomas; Zhang, Hongsheng

2015-12-01

This paper describes the design, development and testing of an AR system that was developed for aerospace and ground vehicles to meet stringent accuracy and robustness requirements. The system uses an optical see-through HMD, and thus requires extremely low latency, high tracking accuracy and precision alignment and calibration of all subsystems in order to avoid mis-registration and "swim". The paper focuses on the optical/inertial hybrid tracking system and describes novel solutions to the challenges with the optics, algorithms, synchronization, and alignment with the vehicle and HMD systems. Tracker accuracy is presented with simulation results to predict the registration accuracy. A car test is used to create a through-the-eyepiece video demonstrating well-registered augmentations of the road and nearby structures while driving. Finally, a detailed covariance analysis of AR registration error is derived.

The Stringent Response Controls Catalases in Pseudomonas aeruginosa and Is Required for Hydrogen Peroxide and Antibiotic Tolerance

PubMed Central

Khakimova, Malika; Ahlgren, Heather G.; Harrison, Joe J.; English, Ann M.

2013-01-01

Pseudomonas aeruginosa, a human opportunistic pathogen, possesses a number of antioxidant defense enzymes under the control of multiple regulatory systems. We recently reported that inactivation of the P. aeruginosa stringent response (SR), a starvation stress response controlled by the alarmone (p)ppGpp, caused impaired antioxidant defenses and antibiotic tolerance. Since catalases are key antioxidant enzymes in P. aeruginosa, we compared the levels of H2O2 susceptibility and catalase activity in P. aeruginosa wild-type and ΔrelA ΔspoT (ΔSR) mutant cells. We found that the SR was required for optimal catalase activity and mediated H2O2 tolerance during both planktonic and biofilm growth. Upon amino acid starvation, induction of the SR upregulated catalase activity. Full expression of katA and katB also required the SR, and this regulation occurred through both RpoS-independent and RpoS-dependent mechanisms. Furthermore, overexpression of katA was sufficient to restore H2O2 tolerance and to partially rescue the antibiotic tolerance of ΔSR cells. All together, these results suggest that the SR regulates catalases and that this is an important mechanism in protecting nutrient-starved and biofilm bacteria from H2O2- and antibiotic-mediated killing. PMID:23457248

A high-temperature furnace for applications in microgravity

NASA Technical Reports Server (NTRS)

1991-01-01

Technology in the area of material processing and crystal growth has been greatly furthered by research in microgravity environments. The role of efficient, lightweight furnaces with reliable performance is crucial in these experiments. A need exists for the development of a readily duplicated, high-temperature furnace satisfying stringent weight, volume, and power constraints. A furnace was designed and is referred to as the UAH SHIELD. Stringent physical and operating characteristics for the system were specified, including a maximum weight of 20 kg, a maximum power requirement of 60 W, and a volume of the furnace assembly, excluding the batteries, limited to half a Get-Away-Special canister. The UAH SHIELD furnace uses radiation shield and vacuum technology applied in the form of a series of concentric cylinders enclosed on either end with disks. Thermal testing of a furnace prototype was performed in addition to some thermal and structural analysis. Results indicate the need for spacing of the shields to accommodate the thermal expansion during furnace operation. In addition, a power dissipation of approximately 100 W and system weight of approximately 30 kg was found for the current design.

Astrometric Telescope Facility isolation and pointing study

NASA Technical Reports Server (NTRS)

Hibble, William; Allen, Terry; Jackson, Louis; Medbery, James; Self, Richard

1988-01-01

The Astrometric Telescope Facility (ATF), an optical telescope designed to detect extrasolar planetary systems, is scheduled to be a major user of the Space Station's Payload Pointing System (PPS). However, because the ATF has such a stringent pointing stability specification and requires + or - 180 deg roll about its line of sight, mechanisms to enhance the basic PPS capability are required. The ATF pointing performance achievable by the addition of a magnetic isolation and pointing system (MIPS) between the PPS upper gimbal and the ATF, and separately, by the addition of a passive isolation system between the Space Station and the PPS base was investigated. The candidate MIPS can meet the ATF requirements in the presence of a 0.01 g disturbance. It fits within the available annular region between the PPS and the ATF while meeting power and weight limitations and providing the required roll motion, payload data and power services. By contrast, the passive base isolator system must have an unrealistically low isolation bandwidth on all axes to meet ATF pointing requirements and does not provide roll about the line of sight.

Towards an operational fault isolation expert system for French telecommunication satellite Telecom 2

NASA Astrophysics Data System (ADS)

Haziza, M.

1990-10-01

The DIAMS satellite fault isolation expert system shell concept is described. The project, initiated in 1985, has led to the development of a prototype Expert System (ES) dedicated to the Telecom 1 attitude and orbit control system. The prototype ES has been installed in the Telecom 1 satellite control center and evaluated by Telecom 1 operations. The development of a fault isolation ES covering a whole spacecraft (the French telecommunication satellite Telecom 2) is currently being undertaken. Full scale industrial applications raise stringent requirements in terms of knowledge management and software development methodology. The approach used by MATRA ESPACE to face this challenge is outlined.

The LLRF System for the S-Band RF Plants of the FERMI Linac

NASA Astrophysics Data System (ADS)

Fabris, A.; Byrd, J.; D'Auria, G.; Doolittle, L.; Gelmetti, F.; Huang, G.; Jones, J.; Milloch, M.; Predonzani, M.; Ratti, A.; Rohlev, T.; Salom, A.; Serrano, C.; Stettler, M.

2016-04-01

Specifications on electron beam quality for the operation of a linac-based free-electron laser (FEL), as FERMI in Trieste (Italy), impose stringent requirements on the stability of the electromagnetic fields of the accelerating sections. These specifications can be met only with state-of-the-art low-level RF (LLRF) systems based on advanced digital technologies. Design considerations, construction, and performance results of the FERMI digital LLRF are presented in this paper. The stability requirements derived by simulations are better than 0.1% in amplitude and 0.1° S-band in phase. The system installed in the FERMI Linac S-band RF plants has met these specifications and is in operation on a 24-h basis as a user facility. Capabilities of the system allow planning for new developments that are also described here.

Reliability Assessment for COTS Components in Space Flight Applications

NASA Technical Reports Server (NTRS)

Krishnan, G. S.; Mazzuchi, Thomas A.

2001-01-01

Systems built for space flight applications usually demand very high degree of performance and a very high level of accuracy. Hence, the design engineers are often prone to selecting state-of-art technologies for inclusion in their system design. The shrinking budgets also necessitate use of COTS (Commercial Off-The-Shelf) components, which are construed as being less expensive. The performance and accuracy requirements for space flight applications are much more stringent than those for the commercial applications. The quantity of systems designed and developed for space applications are much lower in number than those produced for the commercial applications. With a given set of requirements, are these COTS components reliable? This paper presents a model for assessing the reliability of COTS components in space applications and the associated affect on the system reliability. We illustrate the method with a real application.

A rigid and thermally stable all ceramic optical support bench assembly for the LSST Camera

NASA Astrophysics Data System (ADS)

Kroedel, Matthias; Langton, J. Brian; Wahl, Bill

2017-09-01

This paper will present the ceramic design, fabrication and metrology results and assembly plan of the LSST camera optical bench structure which is using the unique manufacturing features of the HB-Cesic technology. The optical bench assembly consists of a rigid "Grid" fabrication supporting individual raft plates mounting sensor assemblies by way of a rigid kinematic support system to meet extreme stringent requirements for focal plane planarity and stability.

Tunable, Flexible and Efficient Optimization of Control Pulses for Superconducting Qubits, part I - Theory

NASA Astrophysics Data System (ADS)

Machnes, Shai; AsséMat, Elie; Tannor, David; Wilhelm, Frank

Quantum computation places very stringent demands on gate fidelities, and experimental implementations require both the controls and the resultant dynamics to conform to hardware-specific ansatzes and constraints. Superconducting qubits present the additional requirement that pulses have simple parametrizations, so they can be further calibrated in the experiment, to compensate for uncertainties in system characterization. We present a novel, conceptually simple and easy-to-implement gradient-based optimal control algorithm, GOAT, which satisfies all the above requirements. In part II we shall demonstrate the algorithm's capabilities, by using GOAT to optimize fast high-accuracy pulses for two leading superconducting qubits architectures - Xmons and IBM's flux-tunable couplers.

EMI Performance of the AIRS Cooler and Electronics

NASA Technical Reports Server (NTRS)

Johnson, D.; Collins, S.; Ross, R.

1998-01-01

The TRW pulse tube cryocooler for JPL's Atmospheric Infrared Sounder (AIRS) instrument is required to meet stringent requirements for radiated electric and magnetic fields, conducted emissions on the input power bus, and electromagnetic susceptivility.

System Identification for Nonlinear Control Using Neural Networks

NASA Technical Reports Server (NTRS)

Stengel, Robert F.; Linse, Dennis J.

1990-01-01

An approach to incorporating artificial neural networks in nonlinear, adaptive control systems is described. The controller contains three principal elements: a nonlinear inverse dynamic control law whose coefficients depend on a comprehensive model of the plant, a neural network that models system dynamics, and a state estimator whose outputs drive the control law and train the neural network. Attention is focused on the system identification task, which combines an extended Kalman filter with generalized spline function approximation. Continual learning is possible during normal operation, without taking the system off line for specialized training. Nonlinear inverse dynamic control requires smooth derivatives as well as function estimates, imposing stringent goals on the approximating technique.

Advanced technology needs for a global change science program: Perspective of the Langley Research Center

NASA Technical Reports Server (NTRS)

Rowell, Lawrence F.; Swissler, Thomas J.

1991-01-01

The focus of the NASA program in remote sensing is primarily the Earth system science and the monitoring of the Earth global changes. One of NASA's roles is the identification and development of advanced sensing techniques, operational spacecraft, and the many supporting technologies necessary to meet the stringent science requirements. Langley Research Center has identified the elements of its current and proposed advanced technology development program that are relevant to global change science according to three categories: sensors, spacecraft, and information system technologies. These technology proposals are presented as one-page synopses covering scope, objective, approach, readiness timeline, deliverables, and estimated funding. In addition, the global change science requirements and their measurement histories are briefly discussed.

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.

Inertial Navigation System for India's Reusable Launch Vehicle-Technology Demonstrator (RLV-TD HEX) Mission

NASA Astrophysics Data System (ADS)

Umadevi, P.; Navas, A.; Karuturi, Kesavabrahmaji; Shukkoor, A. Abdul; Kumar, J. Krishna; Sreekumar, Sreejith; Basim, A. Mohammed

2017-12-01

This work presents the configuration of Inertial Navigation System (INS) used in India's Reusable Launch Vehicle-Technology Demonstrator (RLV-TD) Program. In view of the specific features and requirements of the RLV-TD, specific improvements and modifications were required in the INS. A new system was designed, realised and qualified meeting the mission requirements of RLV-TD, at the same time taking advantage of the flight heritage attained in INS through various Launch vehicle Missions of the country. The new system has additional redundancy in acceleration channel, in-built inclinometer based bias update scheme for acceleration channels and sign conventions as employed in an aircraft. Data acquisition in micro cycle periodicity (10 ms) was incorporated which was required to provide rate and attitude information at higher sampling rate for ascent phase control. Provision was incorporated for acquisition of rate and acceleration data with high resolution for aerodynamic characterisation and parameter estimation. GPS aided navigation scheme was incorporated to meet the stringent accuracy requirements of the mission. Navigation system configuration for RLV-TD, specific features incorporated to meet the mission requirements, various tests carried out and performance during RLV-TD flight are highlighted.

Space Shuttle Solid Rocket Booster decelerator subsystem - Air drop test vehicle/B-52 design

NASA Technical Reports Server (NTRS)

Runkle, R. E.; Drobnik, R. F.

1979-01-01

The air drop development test program for the Space Shuttle Solid Rocket Booster Recovery System required the design of a large drop test vehicle that would meet all the stringent requirements placed on it by structural loads, safety considerations, flight recovery system interfaces, and sequence. The drop test vehicle had to have the capability to test the drogue and the three main parachutes both separately and in the total flight deployment sequence and still be low-cost to fit in a low-budget development program. The design to test large ribbon parachutes to loads of 300,000 pounds required the detailed investigation and integration of several parameters such as carrier aircraft mechanical interface, drop test vehicle ground transportability, impact point ground penetration, salvageability, drop test vehicle intelligence, flight design hardware interfaces, and packaging fidelity.

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.

Results of the Advanced Space Structures Technology Research Experiments (ASTREX) hardware and control development

NASA Technical Reports Server (NTRS)

Cossey, Derek F.

1993-01-01

Future DOD, NASA, and SDI space systems will be larger than any spacecraft flown before. The economics of placing these Precision Space Systems (PSS) into orbit dictates that they be as low in mass as possible. This stringent weight reduction creates structural flexibility causing severe technical problems when combined with the precise shape and pointing requirements associated with many future PSS missions. Development of new Control Structure Interaction (CSI) technologies which can solve these problems and enable future space missions is being conducted at the Phillips Laboratory, On-Location Site, CA.

Continued Development of a Precision Cryogenic Dilatometer for the James Webb Space Telescope

NASA Technical Reports Server (NTRS)

Karlmann, Paul B.; Dudik, Matthew J.; Halverson, Peter G.; Levine, Marie; Marcin, Martin; Peters, Robert D.; Shaklan, Stuart; VanBuren, David

2004-01-01

As part of the James Webb Space Telescope (JWST) materials working group, a novel cryogenic dilatometer was designed and built at NASA Jet Propulsion Laboratory to help address stringent coefficient of thermal expansion (CTE) knowledge requirements. Previously reported results and error analysis have estimated a CTE measurement accuracy for ULE of 1.7 ppb/K with a 20K thermal load and 0.1 ppb/K with a 280K thermal load. Presented here is a further discussion of the cryogenic dilatometer system and a description of recent work including system modifications and investigations.

Flight Hardware Packaging Design for Stringent EMC Radiated Emission Requirements

NASA Technical Reports Server (NTRS)

Lortz, Charlene L.; Huang, Chi-Chien N.; Ravich, Joshua A.; Steiner, Carl N.

2013-01-01

This packaging design approach can help heritage hardware meet a flight project's stringent EMC radiated emissions requirement. The approach requires only minor modifications to a hardware's chassis and mainly concentrates on its connector interfaces. The solution is to raise the surface area where the connector is mounted by a few millimeters using a pedestal, and then wrapping with conductive tape from the cable backshell down to the surface-mounted connector. This design approach has been applied to JPL flight project subsystems. The EMC radiated emissions requirements for flight projects can vary from benign to mission critical. If the project's EMC requirements are stringent, the best approach to meet EMC requirements would be to design an EMC control program for the project early on and implement EMC design techniques starting with the circuit board layout. This is the ideal scenario for hardware that is built from scratch. Implementation of EMC radiated emissions mitigation techniques can mature as the design progresses, with minimal impact to the design cycle. The real challenge exists for hardware that is planned to be flown following a built-to-print approach, in which heritage hardware from a past project with a different set of requirements is expected to perform satisfactorily for a new project. With acceptance of heritage, the design would already be established (circuit board layout and components have already been pre-determined), and hence any radiated emissions mitigation techniques would only be applicable at the packaging level. The key is to take a heritage design with its known radiated emissions spectrum and repackage, or modify its chassis design so that it would have a better chance of meeting the new project s radiated emissions requirements.

Mars sample collection and preservation

NASA Technical Reports Server (NTRS)

Blanchard, Douglas P.

1988-01-01

The intensive exploration of Mars is a major step in the systematic exploration of the solar system. Mars, earth, and Venus provide valuable contrasts in planetary evolution. Mars exploration has progressed through the stages of exploration and is now ready for a sample-return mission. About 5 kg of intelligently selected samples will be returned from Mars. A variety of samples are wanted. This requires accurate landing in areas of high interest, surface mobility and analytical capability, a variety of sampling tools, and stringent preservation and isolation measures.

Defense Infrastructure: Documentation Lacking to Fully Support How DOD Determined Specifications for the Landstuhl Replacement Medical Center

DTIC Science & Technology

2012-05-01

LEED system awards points for meeting a variety of standards and certifies buildings as silver, gold , or platinum. The replacement medical center’s...indicate that it may qualify for a “ gold ” certification once it has met the more stringent German design requirements. For example, the project will... Joanne Landesman assisted in the message and report development, Amie Steele assisted in developing the report’s tables and graphics, Jennifer Echard

Department of Defense Review of the Foreign Comparative Testing Program FY2005-FY2006

DTIC Science & Technology

2007-04-01

Kingdom as a potential alternative to an ongoing domestic development program, which was failing to meet the size, weight , and cost objectives. The...Norway, Switzerland NAMMO, Oerlikon Contraves 0.50 USMC 40mm Training Cartridge MK281 Germany Nico Pyrotechnik 13.14 USMC High Rate-of-Fire .50 Cal...late FY 2003 and, although the system performed as advertised, it did not meet stringent weight requirements. In FY 2005, a down-sized version of

Magnetostrictive valve

NASA Technical Reports Server (NTRS)

Casabianca, C. C.

1978-01-01

Device requires no moving parts and has less stringent tolerances. Device uses magnetostrictive powdered metal and electromagnets, rather than solenoid. Device is more reliable than conventional valves.

The Space Station Prototype Program - The development of a regenerative life support system for extended-duration missions.

NASA Technical Reports Server (NTRS)

Willis, N. C., Jr.; Neel, J. M.

1972-01-01

Design concepts and test philosophies which may contribute to the development of a low-cost maintainable environmental control/life support system are examined. It is shown that the concept of producing flight prototype equipment during a developmental program can reduce the eventual cost of a flight system by incorporating realistic flight-type design requirements without imposing exacting design features and stringent controls. A flight prototype design is one that can be converted readily into an actual flight design without any conceptual change. Modularity of subsystems provides the system and the program a degree of flexibility relative to the eventual vehicle configuration and technological improvements.

Theory and design of interferometric synthetic aperture radars

NASA Technical Reports Server (NTRS)

Rodriguez, E.; Martin, J. M.

1992-01-01

A derivation of the signal statistics, an optimal estimator of the interferometric phase, and the expression necessary to calculate the height-error budget are presented. These expressions are used to derive methods of optimizing the parameters of the interferometric synthetic aperture radar system (InSAR), and are then employed in a specific design example for a system to perform high-resolution global topographic mapping with a one-year mission lifetime, subject to current technological constraints. A Monte Carlo simulation of this InSAR system is performed to evaluate its performance for realistic topography. The results indicate that this system has the potential to satisfy the stringent accuracy and resolution requirements for geophysical use of global topographic data.

Development of Temperature Sensitive Paints for the Detection of Small Temperature Differences

NASA Technical Reports Server (NTRS)

Oglesby, Donald M.; Upchurch, Billy T.; Sealey, Bradley S.; Leighty, Bradley D.; Burkett, Cecil G., Jr.; Jalali, Amir

1997-01-01

Temperature sensitive paints (TSP s) have recently been used to detect small temperature differences on aerodynamic model surfaces. These types of applications impose stringent performance requirements on a paint system. The TSP s must operate over a broad temperature range, must be physically robust (cannot chip or peel), must be polishable to at least the smoothness of the model surface, and must have sufficient sensitivity to detect small temperature differences. TSP coatings based on the use of metal complexes in polymer binders were developed at NASA Langley Research Center which meet most of the requirements for detection of small temperature differences under severe environmental conditions.

Intelligent tutoring in the spacecraft command/control environment

NASA Technical Reports Server (NTRS)

Truszkowski, Walter F.

1988-01-01

The spacecraft command/control environment is becoming increasingly complex. As we enter the era of Space Station and the era of more highly automated systems, it is evident that the critical roles played by operations personnel in supervising the many required control center system components is becoming more cognitively demanding. In addition, the changing and emerging roles in the operations picture have far-reaching effects on the achievement of mission objectives. Thus highly trained and competent operations personnel are mandatory for success. Keeping pace with these developments has been computer-aided instruction utilizing various artificial intelligence technologies. The impacts of this growing capability on the stringent requirements for efficient and effective control center operations personnel is an area of much concentrated study. Some of the research and development of automated tutoring systems for the spacecraft command/control environment is addressed.

The effect of timing errors in optical digital systems.

NASA Technical Reports Server (NTRS)

Gagliardi, R. M.

1972-01-01

The use of digital transmission with narrow light pulses appears attractive for data communications, but carries with it a stringent requirement on system bit timing. The effects of imperfect timing in direct-detection (noncoherent) optical binary systems are investigated using both pulse-position modulation and on-off keying for bit transmission. Particular emphasis is placed on specification of timing accuracy and an examination of system degradation when this accuracy is not attained. Bit error probabilities are shown as a function of timing errors from which average error probabilities can be computed for specific synchronization methods. Of significance is the presence of a residual or irreducible error probability in both systems, due entirely to the timing system, which cannot be overcome by the data channel.

An asymmetric resonant coupling wireless power transmission link for Micro-Ball Endoscopy.

PubMed

Sun, Tianjia; Xie, Xiang; Li, Guolin; Gu, Yingke; Deng, Yangdong; Wang, Ziqiang; Wang, Zhihua

2010-01-01

This paper investigates the design and optimization of a wireless power transmission link targeting Micro-Ball Endoscopy applications. A novel asymmetric resonant coupling structure is proposed to deliver power to an endoscopic Micro-Ball system for image read-out after it is excreted. Such a technology enables many key medical applications with stringent requirements for small system volume and high power delivery efficiency. A prototyping power transmission sub-system of the Micro-Ball system was implemented. It consists of primary coil, middle resonant coil, and cube-like full-direction secondary receiving coils. Our experimental results proved that 200mW of power can be successfully delivered. Such a wireless power transmission capability could satisfy the requirements of the Micro-Ball based endoscopy application. The transmission efficiency is in the range of 41% (worst working condition) to 53% (best working condition). Comparing to conventional structures, Asymmetric Resonant Coupling Structure improves power efficiency by 13%.

Multi-gigabit WDM optical networking for next generation avionics system communications

NASA Astrophysics Data System (ADS)

Gardner, Robert D.; Andonovic, I.; Hunter, D. K.; Hamoudi, A.; McLaughlin, A. J.; Aitchison, J. S.; Marsh, J. H.

2000-04-01

It is envisaged that photonic networking will play a significant role in improving performance and reliability in both civil and military avionics systems. Of all the available photonic multiplexing technologies, wavelength-division multiplexing (WDM) has been the primary focus of attention within mainstream telecommunications offering increased throughput at a reasonable cost, with scope for enhanced routing flexibility, connectivity and network survivability. A direct mapping of techniques and devices from the maturing telecommunications sector is, however, not possible because of the stringent requirements of systems operating in the hostile aerospace environment. This paper gives an outline of these requirements and discusses, in detail, the design and development of a multi-gigabit, broadband optical WDM network architecture, specifically for use on aerospace platforms. The paper will also discuss a key element in the system, the arrayed-waveguide grating (AWG) wavelength multiplexing component, which has been designed to allow operation over the full military temperature specification without environmental conditioning.

Fimag: the United Kingdom disaster victim/forensic identification imaging system.

PubMed

Rutty, Guy N; Robinson, Claire; Morgan, Bruno; Black, Sue; Adams, Catherine; Webster, Philip

2009-11-01

Imaging is an integral diagnostic tool in mass fatality investigations undertaken traditionally by plain X-rays, fluoroscopy, and dental radiography. However, little attention has been given to appropriate image reporting, secure data transfer and storage particularly in relation to the need to meet stringent judicial requirements. Notwithstanding these limitations, it is the risk associated with the safe handling and investigation of contaminated fatalities which is providing new challenges for mass fatality radiological imaging. Mobile multi-slice computed tomography is an alternative to these traditional modalities as it provides a greater diagnostic yield and an opportunity to address the requirements of the criminal justice system. We present a new national disaster victim/forensic identification imaging system--Fimag--which is applicable for both contaminated and non-contaminated mass fatality imaging and addresses the issues of judicial reporting. We suggest this system opens a new era in radiological diagnostics for mass fatalities.

Energy Efficient Engine (E3) combustion system component technology performance report

NASA Technical Reports Server (NTRS)

Burrus, D. L.; Chahrour, C. A.; Foltz, H. L.; Sabla, P. E.; Seto, S. P.; Taylor, J. R.

1984-01-01

The Energy Efficient Engine (E3) combustor effort was conducted as part of the overall NASA/GE E3 Program. This effort included the selection of an advanced double-annular combustion system design. The primary intent of this effort was to evolve a design that meets the stringent emissions and life goals of the E3, as well as all of the usual performance requirements of combustion systems for modern turbofan engines. Numerous detailed design studies were conducted to define the features of the combustion system design. Development test hardware was fabricated, and an extensive testing effort was undertaken to evaluate the combustion system subcomponents in order to verify and refine the design. Technology derived from this effort was incorporated into the engine combustion hardware design. The advanced engine combustion system was then evaluated in component testing to verify the design intent. What evolved from this effort was an advanced combustion system capable of satisfying all of the combustion system design objectives and requirements of the E3.

An Aircraft Separation Algorithm with Feedback and Perturbation

NASA Technical Reports Server (NTRS)

White, Allan L.

2010-01-01

A separation algorithm is a set of rules that tell aircraft how to maneuver in order to maintain a minimum distance between them. This paper investigates demonstrating that separation algorithms satisfy the FAA requirement for the occurrence of incidents by means of simulation. Any demonstration that a separation algorithm, or any other aspect of flight, satisfies the FAA requirement is a challenge because of the stringent nature of the requirement and the complexity of airspace operations. The paper begins with a probability and statistical analysis of both the FAA requirement and demonstrating meeting it by a Monte Carlo approach. It considers the geometry of maintaining separation when one plane must change its flight path. It then develops a simple feedback control law that guides the planes on their paths. The presence of feedback control permits the introduction of perturbations, and the stochastic nature of the chosen perturbation is examined. The simulation program is described. This paper is an early effort in the realistic demonstration of a stringent requirement. Much remains to be done.

Context-Aware Reviewer Assignment for Trust Enhanced Peer Review

PubMed Central

Li, Lei; Wang, Yan; Liu, Guanfeng; Wang, Meng; Wu, Xindong

2015-01-01

Reviewer assignment is critical to peer review systems, such as peer-reviewed research conferences or peer-reviewed funding applications, and its effectiveness is a deep concern of all academics. However, there are some problems in existing peer review systems during reviewer assignment. For example, some of the reviewers are much more stringent than others, leading to an unfair final decision, i.e., some submissions (i.e., papers or applications) with better quality are rejected. In this paper, we propose a context-aware reviewer assignment for trust enhanced peer review. More specifically, in our approach, we first consider the research area specific expertise of reviewers, and the institution relevance and co-authorship between reviewers and authors, so that reviewers with the right expertise are assigned to the corresponding submissions without potential conflict of interest. In addition, we propose a novel cross-assignment paradigm, and reviewers are cross-assigned in order to avoid assigning a group of stringent reviewers or a group of lenient reviewers to the same submission. More importantly, on top of them, we propose an academic CONtext-aware expertise relevanCe oriEnted Reviewer cross-assignmenT approach (CONCERT), which aims to effectively estimate the “true” ratings of submissions based on the ratings from all reviewers, even though no prior knowledge exists about the distribution of stringent reviewers and lenient reviewers. The experiments illustrate that compared with existing approaches, our proposed CONCERT approach can less likely assign more than one stringent reviewers or lenient reviewers to a submission simultaneously and significantly reduce the influence of ratings from stringent reviewers and lenient reviewers, leading to trust enhanced peer review and selection, no matter what kind of distributions of stringent reviewers and lenient reviewers are. PMID:26090849

Tunable, Flexible, and Efficient Optimization of Control Pulses for Practical Qubits

NASA Astrophysics Data System (ADS)

Machnes, Shai; Assémat, Elie; Tannor, David; Wilhelm, Frank K.

2018-04-01

Quantum computation places very stringent demands on gate fidelities, and experimental implementations require both the controls and the resultant dynamics to conform to hardware-specific constraints. Superconducting qubits present the additional requirement that pulses must have simple parameterizations, so they can be further calibrated in the experiment, to compensate for uncertainties in system parameters. Other quantum technologies, such as sensing, require extremely high fidelities. We present a novel, conceptually simple and easy-to-implement gradient-based optimal control technique named gradient optimization of analytic controls (GOAT), which satisfies all the above requirements, unlike previous approaches. To demonstrate GOAT's capabilities, with emphasis on flexibility and ease of subsequent calibration, we optimize fast coherence-limited pulses for two leading superconducting qubits architectures—flux-tunable transmons and fixed-frequency transmons with tunable couplers.

30 CFR 810.4 - Responsibility.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PERMANENT PROGRAM...) The Director shall ensure that performance standards and design requirements at least as stringent as... State regulatory authority shall ensure that performance standards and design requirements at least as...

Thermal design of the space shuttle external tank

NASA Technical Reports Server (NTRS)

Bachrtel, F. D.; Vaniman, J. L.; Stuckey, J. M.; Gray, C.; Widofsky, B.

1985-01-01

The shuttle external tank thermal design presents many challenges in meeting the stringent requirements established by the structures, main propulsion systems, and Orbiter elements. The selected thermal protection design had to meet these requirements, and ease of application, suitability for mass production considering low weight, cost, and high reliability. This development led to a spray-on-foam (SOFI) which covers the entire tank. The need and design for a SOFI material with a dual role of cryogenic insulation and ablator, and the development of the SOFI over SLA concept for high heating areas are discussed. Further issuses of minimum surface ice/frost, no debris, and the development of the TPS spray process considering the required quality and process control are examined.

The FoReVer Methodology: A MBSE Framework for Formal Verification

NASA Astrophysics Data System (ADS)

Baracchi, Laura; Mazzini, Silvia; Cimatti, Alessandro; Tonetta, Stefano; Garcia, Gerald

2013-08-01

The need for high level of confidence and operational integrity in critical space (software) systems is well recognized in the Space industry and has been addressed so far through rigorous System and Software Development Processes and stringent Verification and Validation regimes. The Model Based Space System Engineering process (MBSSE) derived in the System and Software Functional Requirement Techniques study (SSFRT) focused on the application of model based engineering technologies to support the space system and software development processes, from mission level requirements to software implementation through model refinements and translations. In this paper we report on our work in the ESA-funded FoReVer project where we aim at developing methodological, theoretical and technological support for a systematic approach to the space avionics system development, in phases 0/A/B/C. FoReVer enriches the MBSSE process with contract-based formal verification of properties, at different stages from system to software, through a step-wise refinement approach, with the support for a Software Reference Architecture.

Design Tools for Cost-Effective Implementation of Planetary Protection Requirements

NASA Technical Reports Server (NTRS)

Hamlin, Louise; Belz, Andrea; Evans, Michael; Kastner, Jason; Satter, Celeste; Spry, Andy

2006-01-01

Since the Viking missions to Mars in the 1970s, accounting for the costs associated with planetary protection implementation has not been done systematically during early project formulation phases, leading to unanticipated costs during subsequent implementation phases of flight projects. The simultaneous development of more stringent planetary protection requirements, resulting from new knowledge about the limits of life on Earth, together with current plans to conduct life-detection experiments on a number of different solar system target bodies motivates a systematic approach to integrating planetary protection requirements and mission design. A current development effort at NASA's Jet Propulsion Laboratory is aimed at integrating planetary protection requirements more fully into the early phases of mission architecture formulation and at developing tools to more rigorously predict associated cost and schedule impacts of architecture options chosen to meet planetary protection requirements.

A microdisplay-based HUD for automotive applications: Backplane design, planarization, and optical implementation

NASA Astrophysics Data System (ADS)

Schuck, Miller Harry

Automotive head-up displays require compact, bright, and inexpensive imaging systems. In this thesis, a compact head-up display (HUD) utilizing liquid-crystal-on-silicon microdisplay technology is presented from concept to implementation. The thesis comprises three primary areas of HUD research: the specification, design and implementation of a compact HUD optical system, the development of a wafer planarization process to enhance reflective device brightness and light immunity and the design, fabrication and testing of an inexpensive 640 x 512 pixel active matrix backplane intended to meet the HUD requirements. The thesis addresses the HUD problem at three levels, the systems level, the device level, and the materials level. At the systems level, the optical design of an automotive HUD must meet several competing requirements, including high image brightness, compact packaging, video-rate performance, and low cost. An optical system design which meets the competing requirements has been developed utilizing a fully-reconfigurable reflective microdisplay. The design consists of two optical stages, the first a projector stage which magnifies the display, and a second stage which forms the virtual image eventually seen by the driver. A key component of the optical system is a diffraction grating/field lens which forms a large viewing eyebox while reducing the optical system complexity. Image quality biocular disparity and luminous efficacy were analyzed and results of the optical implementation are presented. At the device level, the automotive HUD requires a reconfigurable, video-rate, high resolution image source for applications such as navigation and night vision. The design of a 640 x 512 pixel active matrix backplane which meets the requirements of the HUD is described. The backplane was designed to produce digital field sequential color images at video rates utilizing fast switching liquid crystal as the modulation layer. The design methodology is discussed, and the example of a clock generator is described from design to implementation. Electrical and optical test results of the fabricated backplane are presented. At the materials level, a planarization method was developed to meet the stringent brightness requirements of automotive HUD's. The research efforts described here have resulted in a simple, low cost post-processing method for planarizing microdisplay substrates based on a spin-cast polymeric resin, benzocyclobutene (BCB). Six- fold reductions in substrate step height were accomplished with a single coating. Via masking and dry etching methods were developed. High reflectivity metal was deposited and patterned over the planarized substrate to produce high aperture pixel mirrors. The process is simple, rapid, and results in microdisplays better able to meet the stringent requirements of high brightness display systems. Methods and results of the post- processing are described.

Turbofan Engine Core Compartment Vent Aerodynamic Configuration Development Methodology

NASA Technical Reports Server (NTRS)

Hebert, Leonard J.

2006-01-01

This paper presents an overview of the design methodology used in the development of the aerodynamic configuration of the nacelle core compartment vent for a typical Boeing commercial airplane together with design challenges for future design efforts. Core compartment vents exhaust engine subsystem flows from the space contained between the engine case and the nacelle of an airplane propulsion system. These subsystem flows typically consist of precooler, oil cooler, turbine case cooling, compartment cooling and nacelle leakage air. The design of core compartment vents is challenging due to stringent design requirements, mass flow sensitivity of the system to small changes in vent exit pressure ratio, and the need to maximize overall exhaust system performance at cruise conditions.

Evaluation of insulation materials and composites for use in a nuclear radiation environment, phase 1

NASA Technical Reports Server (NTRS)

Greenhow, W. A.; Lewis, J. H.

1972-01-01

This study has been carried out to evaluate flight-qualified Saturn 5 materials, components, and systems for use, with or without modification, in the radiation environment of the nuclear flight system. The results reported herein are primarily intended to aid designers in their evaluation and selection of off-the-shelf equipments which may meet the stringent requirements and specifications associated with application on a reusable nuclear powered space system, i.e., the reusable nuclear shuttle. One of the factors which must be evaluated in the design of the RNS is the effects of radiation on materials; and it is toward this aspect of the overall effort that this analysis has been directed.

The Galileo attitude and articulation control system - A radiation-hard, high precision, state-of-the-art control system

NASA Technical Reports Server (NTRS)

Stephenson, R. Rhoads

1985-01-01

The Galileo mission and spacecraft, consisting of a Jupiter-orbiter and an atmospheric entry probe, are discussed. Components will include: magnetometers and plasma-wave antennas on a boom, high-gain antenna, probe vehicle, two different bus electronics packages, and a radioisotope thermoelectric generator. Instruments, investigators and objectives are tabulated for both probe science and orbiter science investigations. Requirements in the design of the attitude and articulation control system are very stringent because of the complex dynamics, flexible body effects, the need for autonomy, and the severe radiation environment in the Jupiter nighborhood. Galileo was intended to be ready for launch via Space Shuttle in May of 1986.

Operational Challenges In TDRS Post-Maneuver Orbit Determination

NASA Technical Reports Server (NTRS)

Laing, Jason; Myers, Jessica; Ward, Douglas; Lamb, Rivers

2015-01-01

The GSFC Flight Dynamics Facility (FDF) is responsible for daily and post maneuver orbit determination for the Tracking and Data Relay Satellite System (TDRSS). The most stringent requirement for this orbit determination is 75 meters total position accuracy (3-sigma) predicted over one day for Terra's onboard navigation system. To maintain an accurate solution onboard Terra, a solution is generated and provided by the FDF Four hours after a TDRS maneuver. A number of factors present challenges to this support, such as maneuver prediction uncertainty and potentially unreliable tracking from User satellities. Reliable support is provided by comparing an extended Kalman Filter (estimated using ODTK) against a Batch Least Squares system (estimated using GTDS).

Small Body Landing Accuracy Using In-Situ Navigation

NASA Technical Reports Server (NTRS)

Bhaskaran, Shyam; Nandi, Sumita; Broschart, Stephen; Wallace, Mark; Olson, Corwin; Cangahuala, L. Alberto

2011-01-01

Spacecraft landings on small bodies (asteroids and comets) can require target accuracies too stringent to be met using ground-based navigation alone, especially if specific landing site requirements must be met for safety or to meet science goals. In-situ optical observations coupled with onboard navigation processing can meet the tighter accuracy requirements to enable such missions. Recent developments in deep space navigation capability include a self-contained autonomous navigation system (used in flight on three missions) and a landmark tracking system (used experimentally on the Japanese Hayabusa mission). The merging of these two technologies forms a methodology to perform autonomous onboard navigation around small bodies. This paper presents an overview of these systems, as well as the results from Monte Carlo studies to quantify the achievable landing accuracies by using these methods. Sensitivity of the results to variations in spacecraft maneuver execution error, attitude control accuracy and unmodeled forces are examined. Cases for two bodies, a small asteroid and on a mid-size comet, are presented.

Real-time simulation of a Doubly-Fed Induction Generator based wind power system on eMEGASimRTM Real-Time Digital Simulator

NASA Astrophysics Data System (ADS)

Boakye-Boateng, Nasir Abdulai

The growing demand for wind power integration into the generation mix prompts the need to subject these systems to stringent performance requirements. This study sought to identify the required tools and procedures needed to perform real-time simulation studies of Doubly-Fed Induction Generator (DFIG) based wind generation systems as basis for performing more practical tests of reliability and performance for both grid-connected and islanded wind generation systems. The author focused on developing a platform for wind generation studies and in addition, the author tested the performance of two DFIG models on the platform real-time simulation model; an average SimpowerSystemsRTM DFIG wind turbine, and a detailed DFIG based wind turbine using ARTEMiSRTM components. The platform model implemented here consists of a high voltage transmission system with four integrated wind farm models consisting in total of 65 DFIG based wind turbines and it was developed and tested on OPAL-RT's eMEGASimRTM Real-Time Digital Simulator.

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.

Importance of Resolving the Spectral Support of Beam-plasma Instabilities in Simulations

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

Shalaby, Mohamad; Broderick, Avery E.; Chang, Philip

2017-10-20

Many astrophysical plasmas are prone to beam-plasma instabilities. For relativistic and dilute beams, the spectral support of the beam-plasma instabilities is narrow, i.e., the linearly unstable modes that grow with rates comparable to the maximum growth rate occupy a narrow range of wavenumbers. This places stringent requirements on the box-sizes when simulating the evolution of the instabilities. We identify the implied lower limits on the box size imposed by the longitudinal beam plasma instability, i.e., typically the most stringent condition required to correctly capture the linear evolution of the instabilities in multidimensional simulations. We find that sizes many orders ofmore » magnitude larger than the resonant wavelength are typically required. Using one-dimensional particle-in-cell simulations, we show that the failure to sufficiently resolve the spectral support of the longitudinal instability yields slower growth and lower levels of saturation, potentially leading to erroneous physical conclusion.« less

Propagating Qualitative Values Through Quantitative Equations

NASA Technical Reports Server (NTRS)

Kulkarni, Deepak

1992-01-01

In most practical problems where traditional numeric simulation is not adequate, one need to reason about a system with both qualitative and quantitative equations. In this paper, we address the problem of propagating qualitative values represented as interval values through quantitative equations. Previous research has produced exponential-time algorithms for approximate solution of the problem. These may not meet the stringent requirements of many real time applications. This paper advances the state of art by producing a linear-time algorithm that can propagate a qualitative value through a class of complex quantitative equations exactly and through arbitrary algebraic expressions approximately. The algorithm was found applicable to Space Shuttle Reaction Control System model.

Mission Management Computer Software for RLV-TD

NASA Astrophysics Data System (ADS)

Manju, C. R.; Joy, Josna Susan; Vidya, L.; Sheenarani, I.; Sruthy, C. N.; Viswanathan, P. C.; Dinesh, Sudin; Jayalekshmy, L.; Karuturi, Kesavabrahmaji; Sheema, E.; Syamala, S.; Unnikrishnan, S. Manju; Ali, S. Akbar; Paramasivam, R.; Sheela, D. S.; Shukkoor, A. Abdul; Lalithambika, V. R.; Mookiah, T.

2017-12-01

The Mission Management Computer (MMC) software is responsible for the autonomous navigation, sequencing, guidance and control of the Re-usable Launch Vehicle (RLV), through lift-off, ascent, coasting, re-entry, controlled descent and splashdown. A hard real-time system has been designed for handling the mission requirements in an integrated manner and for meeting the stringent timing constraints. Redundancy management and fault-tolerance techniques are also built into the system, in order to achieve a successful mission even in presence of component failures. This paper describes the functions and features of the components of the MMC software which has accomplished the successful RLV-Technology Demonstrator mission.

SIMULATIONS OF TRANSVERSE STACKING IN THE NSLS-II BOOSTER

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

Fliller III, R.; Shaftan, T.

2011-03-28

The NSLS-II injection system consists of a 200 MeV linac and a 3 GeV booster. The linac needs to deliver 15 nC in 80 - 150 bunches to the booster every minute to achieve current stability goals in the storage ring. This is a very stringent requirement that has not been demonstrated at an operating light source. We have developed a scheme to transversely stack two bunch trains in the NSLS-II booster in order to alleviate the charge requirements on the linac. This scheme has been outlined previously. In this paper we show particle tracking simulations of the tracking scheme.more » We show simulations of the booster ramp with a stacked beam for a variety of lattice errors and injected beam parameters. In all cases the performance of the proposed stacking method is sufficient to reduce the required charge from the linac. For this reason the injection system of the NSLS-II booster is being designed to include this feature. The NSLS-II injection system consists of a 200 MeV linac and a 3 GeV booster. The injectors must provide 7.5nC in bunch trains 80-150 bunches long every minute for top off operation of the storage ring. Top off then requires that the linac deliver 15nC of charge once losses in the injector chain are taken into consideration. This is a very stringent requirement that has not been demonstrated at an operating light source. For this reason we have developed a method to transversely stack two bunch trains in the booster while maintaining the charge transport efficiency. This stacking scheme has been discussed previously. In this paper we show the simulations of the booster ramp with a single bunch train in the booster. Then we give a brief overview of the stacking scheme. Following, we show the results of stacking two bunch trains in the booster with varying beam emittances and train separations. The behavior of the beam through the ramp is examined showing that it is possible to stack two bunch trains in the booster.« less

Role of the Stringent Stress Response in the Antibiotic Resistance Phenotype of Methicillin-Resistant Staphylococcus aureus

PubMed Central

Aedo, Sandra

2016-01-01

Resistance to beta-lactam antibiotics in methicillin-resistant Staphylococcus aureus (MRSA) requires the presence of an acquired genetic determinant, mecA or mecC, which encode penicillin-binding protein PBP2A or PBP2A′, respectively. Although all MRSA strains share a mechanism of resistance, the phenotypic expression of beta-lactam resistance shows considerable strain-to-strain variation. The stringent stress response, a stress response that results from nutrient limitation, was shown to play a key role in determining the resistance level of an MRSA strain. In the present study, we validated the impact of the stringent stress response on transcription and translation of mecA in the MRSA clinical isolate strain N315, which also carries known regulatory genes (mecI/mecR1/mecR2 and blaI/blaR1) for mecA transcription. We showed that the impact of the stringent stress response on the resistance level may be restricted to beta-lactam resistance based on a “foreign” determinant such as mecA, as opposed to resistance based on mutations in the native S. aureus determinant pbpB (encoding PBP2). Our observations demonstrate that high-level resistance mediated by the stringent stress response follows the current model of beta-lactam resistance in which the native PBP2 protein is also essential for expression of the resistance phenotype. We also show that the Staphylococcus sciuri pbpD gene (also called mecAI), the putative evolutionary precursor of mecA, confers oxacillin resistance in an S. aureus strain, generating a heterogeneous phenotype that can be converted to high and homogenous resistance by induction of the stringent stress response in the bacteria. PMID:26833147

Environmental Life Cycle Assessment and Cost Analysis of Bath, NY Wastewater Treatment Plant: Potential Upgrade Implications

EPA Science Inventory

Many communities across the U.S. are required to upgrade wastewater treatment plants (WWTP) to meet increasingly stringent nutrient effluent standards. However, increased capital, energy and chemical requirements of upgrades create potential trade-offs between eutrophication pot...

Design, fabrication, and operation of dished accelerator grids on a 30-cm ion thruster

NASA Technical Reports Server (NTRS)

Rawlin, V. K.; Banks, B. A.; Byers, D. C.

1972-01-01

Several closely-space dished accelerator grid systems were fabricated and tested on a 30-cm diameter mercury bombardment thruster and they appear to be a solution to the stringent requirements imposed by the near-term, high-thrust, low specific impulse electric propulsion missions. The grids were simultaneously hydroformed and then simultaneously stress relieved. The ion extraction capability and discharge chamber performance were studied as the total accelerating voltage, the ratio of net-to-total voltage, grid spacing, and dish direction were varied.

Two-dimensional surface strain measurement based on a variation of Yamaguchi's laser-speckle strain gauge

NASA Technical Reports Server (NTRS)

Barranger, John P.

1990-01-01

A novel optical method of measuring 2-D surface strain is proposed. Two linear strains along orthogonal axes and the shear strain between those axes is determined by a variation of Yamaguchi's laser-speckle strain gage technique. It offers the advantages of shorter data acquisition times, less stringent alignment requirements, and reduced decorrelation effects when compared to a previously implemented optical strain rosette technique. The method automatically cancels the translational and rotational components of rigid body motion while simplifying the optical system and improving the speed of response.

RS-84 Engine Completes Design Review

NASA Technical Reports Server (NTRS)

2003-01-01

This is an artist's concept of the kerosene-fueled RS-84 engine, one of several technologies competing to power NASA's next generation of launch vehicles. The RS-84 has successfully completed its preliminary design review as a reusable, liquid kerosene booster engine that will deliver a thrust level of 1 million pounds of force. The preliminary design review is a lengthy technical analysis that evaluates engine design according to stringent system requirements. The review ensures development is on target to meet Next Generation Launch Technology goals: Improved safety, reliability, and cost.

Application of technology developed for flight simulation at NASA. Langley Research Center

NASA Technical Reports Server (NTRS)

Cleveland, Jeff I., II

1991-01-01

In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations including mathematical model computation and data input/output to the simulators must be deterministic and be completed in as short a time as possible. Personnel at NASA's Langley Research Center are currently developing the use of supercomputers for simulation mathematical model computation for real-time simulation. This, coupled with the use of an open systems software architecture, will advance the state-of-the-art in real-time flight simulation.

NASA management of the Space Shuttle Program

NASA Technical Reports Server (NTRS)

Peters, F.

1975-01-01

The management system and management technology described have been developed to meet stringent cost and schedule constraints of the Space Shuttle Program. Management of resources available to this program requires control and motivation of a large number of efficient creative personnel trained in various technical specialties. This must be done while keeping track of numerous parallel, yet interdependent activities involving different functions, organizations, and products all moving together in accordance with intricate plans for budgets, schedules, performance, and interaction. Some techniques developed to identify problems at an early stage and seek immediate solutions are examined.

Reconfigurable Pointing Control for High Resolution Space Spectroscopy

NASA Technical Reports Server (NTRS)

Bayard, David S.; Kia, Tooraj; vanCleve, Jeffrey

1997-01-01

In this paper, a pointing control performance criteria is established to support high resolution space spectroscopy. Results indicate that these pointing requirements are very stringent, and would typically be difficult to meet using standard 3-axis spacecraft control. To resolve this difficulty, it is shown that performance can be significantly improved using a reconfigurable control architecture that switches among a small bank of detuned Kalman filters. The effectiveness of the control reconfiguration approach is demonstrated by example on the Space Infra, Red Telescope Facility (SIRTF) pointing system, in support of the Infrared Spectrograph (IRS) payload.

Materials technology assessment for a 1050 K Stirling space engine design

NASA Technical Reports Server (NTRS)

Scheuermann, Coulson M.; Dreshfield, Robert L.; Gaydosh, Darrell J.; Kiser, James D.; Mackay, Rebecca A.; Mcdaniels, David L.; Petrasek, Donald W.; Vannucci, Raymond D.; Bowles, Kenneth J.; Watson, Gordon K.

1988-01-01

An assessment of materials technology and proposed materials selection was made for the 1050 K (superalloy) Stirling Space Engine design. The objectives of this assessment were to evaluate previously proposed materials selections, evaluate the current state-of-the-art materials, propose potential alternate materials selections and identify research and development efforts needed to provide materials that can meet the stringent system requirements. This assessment generally reaffirmed the choices made by the contractor. However, in many cases alternative choices were described and suggestions for needed materials and fabrication research and development were made.

40 CFR 63.2241 - What are the work practice requirements and how must I meet them?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Products Compliance Options, Operating Requirements, and Work Practice Requirements § 63.2241 What are the...) If you have a dry rotary dryer, you may choose to designate your dry rotary dryer as a green rotary dryer and meet the more stringent compliance options and operating requirements in § 63.2240 for green...

Design, analysis, and testing of high frequency passively damped struts

NASA Technical Reports Server (NTRS)

Yiu, Y. C.; Davis, L. Porter; Napolitano, Kevin; Ninneman, R. Rory

1993-01-01

Objectives of the research are: (1) to develop design requirements for damped struts to stabilize control system in the high frequency cross-over and spill-over range; (2) to design, fabricate and test viscously damped strut and viscoelastically damped strut; (3) to verify accuracy of design and analysis methodology of damped struts; and (4) to design and build test apparatus, and develop data reduction algorithm to measure strut complex stiffness. In order to meet the stringent performance requirements of the SPICE experiment, the active control system is used to suppress the dynamic responses of the low order structural modes. However, the control system also inadvertently drives some of the higher order modes unstable in the cross-over and spill-over frequency range. Passive damping is a reliable and effective way to provide damping to stabilize the control system. It also improves the robustness of the control system. Damping is designed into the SPICE testbed as an integral part of the control-structure technology.

Nutrient Removal and Resource Recovery: Effect on Life Cycle Cost and Environmental Impacts of Small Scale Wastewater Treatment

EPA Science Inventory

Many communities across the U.S. are required to upgrade wastewater treatment plants (WWTP) to meet increasingly stringent nutrient effluent standards. However, increased capital, energy and chemical requirements of upgrades create potential trade-offs between eutrophication pote...

40 CFR 85.525 - Applicable standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... prohibition, vehicles/engines that have been converted to operate on a different fuel must meet emission standards and related requirements as follows: (a) The modified vehicle/engine must meet the requirements that applied for the OEM vehicle/engine, or the most stringent OEM vehicle/engine standards in any...

Technology Requirements For a Square-Meter, Arcsecond-Resolution Telescope for X-Rays: The SMART-X Mission

NASA Technical Reports Server (NTRS)

Schwartz, Daniel A.; Allured, Ryan; Bookbinder, Jay; Cotroneo, Vincenzo; Forman, William; Freeman, Mark; McMuldroch, Stuart; Reid, Paul; Tananbaum, Harvey; Vikhlinin, Alexey;

Characterization of three-way automotive catalysts

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

Kenik, E.A.; More, K.L.; LaBarge, W.

1997-04-01

The CRADA between Delphi Automotive Systems (Delphi; formerly General Motors - AC Delco, Systems) and Lockheed Martin Energy Research (LMER) on automotive catalysts was completed at the end of FY96, after a ten month, no-cost extension. The CRADA was aimed at improved performance and lifetime of noble metal based three-way-catalysts (TWC), which are the primary catalytic system for automotive emission control systems. While these TWC can meet the currently required emission standards, higher than optimum noble metal loadings are often required to meet lifetime requirements. In addition, more stringent emission standards will be imposed in the near future, demanding improvedmore » performance and service life from these catalysts. Understanding the changes of TWC conversion efficiency with ageing is a critical need in improving these catalysts. Initially in a fresh catalyst, the active material is often distributed on a very fine scale, approaching single atoms or small atomic clusters. As such, a wide range of analytical techniques have been employed to provide high spatial resolution characterization of the evolving state of the catalytic material.« less

Oral bioaccessibility testing and read-across hazard assessment of nickel compounds.

PubMed

Henderson, Rayetta G; Cappellini, Danielle; Seilkop, Steven K; Bates, Hudson K; Oller, Adriana R

2012-06-01

In vitro metal ion bioaccessibility, as a measure of bioavailability, can be used to read-across toxicity information from data-rich, source substances to data-poor, target substances. To meet the data requirements for oral systemic toxicity endpoints under the REACH Regulation in Europe, 12 nickel substances underwent bioaccessibility testing in stomach and intestinal fluids. A read-across paradigm was developed based on the correlation between gastric bioaccessibility and in vivo acute oral toxicity. The oral LD₅₀ values were well predicted by nickel release (R² = 0.91). Samples releasing <48% available nickel (mgNi released/mg available Ni × 100) are predicted to have an LD₅₀ > 2000 mg/kg; while samples releasing > 76% available nickel are expected to have an LD₅₀ between 300 and 2000 mg/kg. The hazard classifications (European Regulation on Classification, Labelling and Packaging of Chemical Substances and Mixtures) for all oral systemic endpoints were evaluated based on read-across from three source nickel compounds (sulfate, subsulfide, oxide). Samples releasing < 48% available nickel were read-across from nickel oxides and subsulfide. Samples releasing > 76% Ni were read-across from nickel sulfate. This assessment suggests that nickel chloride and dihydroxide should be less stringently classified and nickel sulfamate should receive a more stringent classification for oral systemic endpoints than currently assigned. Copyright © 2012 Elsevier Inc. All rights reserved.

Development of the risk-based, phased-in approach for the international harmonization of the regulation of container closure systems for drugs in Taiwan.

PubMed

Chang, Lin-Chau; Kang, Jaw-Jou; Gau, Churn-Shiouh

2016-06-01

The main concern for container closure systems of drugs is to ensure suitability for the intended use which is associated with issues regarding protection, compatibility, safety, and performance. Among various concerns, leachables may pose a safety hazard to patients, while risks might vary depending on the dosage form and the administration route. Stringent regulatory authorities such as the European Medicines Agency and the United States Food and Drug Administration have established risk-based regulatory requirements and published corresponding guidelines to facilitate implementation. Taiwan, a member of the Pharmaceutical Inspection Convention and Pharmaceutical Inspection Co-operation Scheme, makes every effort to harmonize with international regulations and to strengthen protection of public health through regulatory controls. The aim of the present study was to investigate the regulatory framework and policies set by stringent regulatory authorities. The strategy proposed for the development of an eventual guideline was sent to the Taiwan Food and Drug Administration for decision. A risk-based, phased-in approach which was extensively discussed in the expert committee was proposed. The approach proposed herein could also serve as a starting point which is worth considered by other countries in which international harmonization is in process. Copyright © 2016 Elsevier Inc. All rights reserved.

78 FR 20039 - Reportable Events and Certain Other Notification Requirements

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-03

...'' test and four other criteria designed to measure various aspects of financial soundness. The credit... controlled group changes. Like section 4043, the reportable events regulation generally requires post-event... available for plans that could meet one of two funding tests that would be more stringent than those...

40 CFR 1039.625 - What requirements apply under the program for equipment-manufacturer flexibility?

Code of Federal Regulations, 2012 CFR

2012-07-01

... NONROAD COMPRESSION-IGNITION ENGINES Special Compliance Provisions § 1039.625 What requirements apply... manufacturers to produce equipment with engines that are subject to less stringent emission standards after the... such equipment without manufacturing it. Engines and equipment you produce under this section are...

40 CFR 1039.625 - What requirements apply under the program for equipment-manufacturer flexibility?

Code of Federal Regulations, 2013 CFR

2013-07-01

... NONROAD COMPRESSION-IGNITION ENGINES Special Compliance Provisions § 1039.625 What requirements apply... manufacturers to produce equipment with engines that are subject to less stringent emission standards after the... such equipment without manufacturing it. Engines and equipment you produce under this section are...

Energy Efficient Engine combustor test hardware detailed design report

NASA Technical Reports Server (NTRS)

Burrus, D. L.; Chahrour, C. A.; Foltz, H. L.; Sabla, P. E.; Seto, S. P.; Taylor, J. R.

1984-01-01

The Energy Efficient Engine (E3) Combustor Development effort was conducted as part of the overall NASA/GE E3 Program. This effort included the selection of an advanced double-annular combustion system design. The primary intent was to evolve a design which meets the stringent emissions and life goals of the E3 as well as all of the usual performance requirements of combustion systems for modern turbofan engines. Numerous detailed design studies were conducted to define the features of the combustion system design. Development test hardware was fabricated, and an extensive testing effort was undertaken to evaluate the combustion system subcomponents in order to verify and refine the design. Technology derived from this development effort will be incorporated into the engine combustion system hardware design. This advanced engine combustion system will then be evaluated in component testing to verify the design intent. What is evolving from this development effort is an advanced combustion system capable of satisfying all of the combustion system design objectives and requirements of the E3. Fuel nozzle, diffuser, starting, and emissions design studies are discussed.

Early Benchmarks of Product Generation Capabilities of the GOES-R Ground System for Operational Weather Prediction

NASA Astrophysics Data System (ADS)

Kalluri, S. N.; Haman, B.; Vititoe, D.

2014-12-01

The ground system under development for Geostationary Operational Environmental Satellite-R (GOES-R) series of weather satellite has completed a key milestone in implementing the science algorithms that process raw sensor data to higher level products in preparation for launch. Real time observations from GOES-R are expected to make significant contributions to Earth and space weather prediction, and there are stringent requirements to product weather products at very low latency to meet NOAA's operational needs. Simulated test data from all the six GOES-R sensors are being processed by the system to test and verify performance of the fielded system. Early results show that the system development is on track to meet functional and performance requirements to process science data. Comparison of science products generated by the ground system from simulated data with those generated by the algorithm developers show close agreement among data sets which demonstrates that the algorithms are implemented correctly. Successful delivery of products to AWIPS and the Product Distribution and Access (PDA) system from the core system demonstrate that the external interfaces are working.

Indexing system for optical beam steering

NASA Technical Reports Server (NTRS)

Sullivan, Mark T.; Cannon, David M.; Debra, Daniel B.; Young, Jeffrey A.; Mansfield, Joseph A.; Carmichael, Roger E.; Lissol, Peter S.; Pryor, G. M.; Miklosy, Les G.; Lee, Jeffrey H.

1990-01-01

This paper describes the design and testing of an indexing system for optical-beam steering. The cryogenic beam-steering mechanism is a 360-degree rotation device capable of discrete, high-precision alignment positions. It uses low-precision components for its rough alignment and kinematic design to meet its stringent repeatability and stability requirements (of about 5 arcsec). The principal advantages of this design include a decoupling of the low-precision, large angular motion from the high-precision alignment, and a power-off alignment position that potentially extends the life or hold time of cryogenic systems. An alternate design, which takes advantage of these attributes while reducing overall motion, is also presented. Preliminary test results show the kinematic mount capable of sub-arc second repeatability.

A Dependable Massive Storage Service for Medical Imaging.

PubMed

Núñez-Gaona, Marco Antonio; Marcelín-Jiménez, Ricardo; Gutiérrez-Martínez, Josefina; Aguirre-Meneses, Heriberto; Gonzalez-Compean, José Luis

2018-05-18

We present the construction of Babel, a distributed storage system that meets stringent requirements on dependability, availability, and scalability. Together with Babel, we developed an application that uses our system to store medical images. Accordingly, we show the feasibility of our proposal to provide an alternative solution for massive scientific storage and describe the software architecture style that manages the DICOM images life cycle, utilizing Babel like a virtual local storage component for a picture archiving and communication system (PACS-Babel Interface). Furthermore, we describe the communication interface in the Unified Modeling Language (UML) and show how it can be extended to manage the hard work associated with data migration processes on PACS in case of updates or disaster recovery.

Flight dynamics facility operational orbit determination support for the ocean topography experiment

NASA Technical Reports Server (NTRS)

Bolvin, D. T.; Schanzle, A. F.; Samii, M. V.; Doll, C. E.

1991-01-01

The Ocean Topography Experiment (TOPEX/POSEIDON) mission is designed to determine the topography of the Earth's sea surface across a 3 yr period, beginning with launch in June 1992. The Goddard Space Flight Center Dynamics Facility has the capability to operationally receive and process Tracking and Data Relay Satellite System (TDRSS) tracking data. Because these data will be used to support orbit determination (OD) aspects of the TOPEX mission, the Dynamics Facility was designated to perform TOPEX operational OD. The scientific data require stringent OD accuracy in navigating the TOPEX spacecraft. The OD accuracy requirements fall into two categories: (1) on orbit free flight; and (2) maneuver. The maneuver OD accuracy requirements are of two types; premaneuver planning and postmaneuver evaluation. Analysis using the Orbit Determination Error Analysis System (ODEAS) covariance software has shown that, during the first postlaunch mission phase of the TOPEX mission, some postmaneuver evaluation OD accuracy requirements cannot be met. ODEAS results also show that the most difficult requirements to meet are those that determine the change in the components of velocity for postmaneuver evaluation.

Toward a Dynamically Reconfigurable Computing and Communication System for Small Spacecraft

NASA Technical Reports Server (NTRS)

Kifle, Muli; Andro, Monty; Tran, Quang K.; Fujikawa, Gene; Chu, Pong P.

2003-01-01

Future science missions will require the use of multiple spacecraft with multiple sensor nodes autonomously responding and adapting to a dynamically changing space environment. The acquisition of random scientific events will require rapidly changing network topologies, distributed processing power, and a dynamic resource management strategy. Optimum utilization and configuration of spacecraft communications and navigation resources will be critical in meeting the demand of these stringent mission requirements. There are two important trends to follow with respect to NASA's (National Aeronautics and Space Administration) future scientific missions: the use of multiple satellite systems and the development of an integrated space communications network. Reconfigurable computing and communication systems may enable versatile adaptation of a spacecraft system's resources by dynamic allocation of the processor hardware to perform new operations or to maintain functionality due to malfunctions or hardware faults. Advancements in FPGA (Field Programmable Gate Array) technology make it possible to incorporate major communication and network functionalities in FPGA chips and provide the basis for a dynamically reconfigurable communication system. Advantages of higher computation speeds and accuracy are envisioned with tremendous hardware flexibility to ensure maximum survivability of future science mission spacecraft. This paper discusses the requirements, enabling technologies, and challenges associated with dynamically reconfigurable space communications systems.

Modeling for Integrated Science Management and Resilient Systems Development

NASA Technical Reports Server (NTRS)

Shelhamer, M.; Mindock, J.; Lumpkins, S.

2014-01-01

Many physiological, environmental, and operational risks exist for crewmembers during spaceflight. An understanding of these risks from an integrated perspective is required to provide effective and efficient mitigations during future exploration missions that typically have stringent limitations on resources available, such as mass, power, and crew time. The Human Research Program (HRP) is in the early stages of developing collaborative modeling approaches for the purposes of managing its science portfolio in an integrated manner to support cross-disciplinary risk mitigation strategies and to enable resilient human and engineered systems in the spaceflight environment. In this talk, we will share ideas being explored from fields such as network science, complexity theory, and system-of-systems modeling. Initial work on tools to support these explorations will be discussed briefly, along with ideas for future efforts.

ARI's Views on ANSI S12.60-2002.

ERIC Educational Resources Information Center

Darbeau, Michele

2003-01-01

States the position of the Air-Conditioning and Refrigeration Institute (ARI) toward ANSI Standard 12.60, which addresses classroom acoustics. Explains why it believes the standard creates an overly stringent requirement. (EV)

Development and manufacture of visor for helmet-mounted display

NASA Astrophysics Data System (ADS)

Krevor, David H.; McNelly, Gregg; Skubon, John; Speirs, Robert

2004-01-01

The manufacturing design and process development for the Visor for the JHMCS (Joint Helmet Mounted Cueing System) are discussed. The JHMCS system is a Helmet Mounted Display (HMD) system currently flying on the F-15, F-16 and F/A-18 aircraft. The Visor manufacturing processes are essential to both system performance and economy. The Visor functions both as the system optical combiner and personal protective equipment for the pilot. The Visor material is optical polycarbonate. For a military HMD system, the mechanical and environmental properties of the Visor are as necessary as the optical properties. The visor must meet stringent dimensional requirements to assure adequate system optical performance. Injection molding can provide dimensional fidelity to the requirements, if done properly. Concurrent design of the visor and the tool (i.e., the injection mold) is essential. The concurrent design necessarily considers manufacturing operations and the use environment of the Visor. Computer modeling of the molding process is a necessary input to the mold design. With proper attention to product design and tool development, it is possible to improve upon published standard dimensional tolerances for molded polycarbonate articles.

Design and Performance of the Terrestrial Planet Finder Coronagraph

NASA Technical Reports Server (NTRS)

White, Mary L.; Shaklan, Stuart; Lisman, P. Doulas; Ho, Timothy; Mouroulis, Pantazis; Basinger, Scott; Ledeboer, Bill; Kwack, Eug; Kissil, Andy; Mosier, Gary;

The stringent response regulates adaptation to darkness in the cyanobacterium Synechococcus elongatus.

PubMed

Hood, Rachel D; Higgins, Sean A; Flamholz, Avi; Nichols, Robert J; Savage, David F

2016-08-16

The cyanobacterium Synechococcus elongatus relies upon photosynthesis to drive metabolism and growth. During darkness, Synechococcus stops growing, derives energy from its glycogen stores, and greatly decreases rates of macromolecular synthesis via unknown mechanisms. Here, we show that the stringent response, a stress response pathway whose genes are conserved across bacteria and plant plastids, contributes to this dark adaptation. Levels of the stringent response alarmone guanosine 3'-diphosphate 5'-diphosphate (ppGpp) rise after a shift from light to dark, indicating that darkness triggers the same response in cyanobacteria as starvation in heterotrophic bacteria. High levels of ppGpp are sufficient to stop growth and dramatically alter many aspects of cellular physiology, including levels of photosynthetic pigments and polyphosphate, DNA content, and the rate of translation. Cells unable to synthesize ppGpp display pronounced growth defects after exposure to darkness. The stringent response regulates expression of a number of genes in Synechococcus, including ribosomal hibernation promoting factor (hpf), which causes ribosomes to dimerize in the dark and may contribute to decreased translation. Although the metabolism of Synechococcus differentiates it from other model bacterial systems, the logic of the stringent response remains remarkably conserved, while at the same time having adapted to the unique stresses of the photosynthetic lifestyle.

The stringent response regulates adaptation to darkness in the cyanobacterium Synechococcus elongatus

PubMed Central

Hood, Rachel D.; Higgins, Sean A.; Flamholz, Avi; Nichols, Robert J.

2016-01-01

The cyanobacterium Synechococcus elongatus relies upon photosynthesis to drive metabolism and growth. During darkness, Synechococcus stops growing, derives energy from its glycogen stores, and greatly decreases rates of macromolecular synthesis via unknown mechanisms. Here, we show that the stringent response, a stress response pathway whose genes are conserved across bacteria and plant plastids, contributes to this dark adaptation. Levels of the stringent response alarmone guanosine 3′-diphosphate 5′-diphosphate (ppGpp) rise after a shift from light to dark, indicating that darkness triggers the same response in cyanobacteria as starvation in heterotrophic bacteria. High levels of ppGpp are sufficient to stop growth and dramatically alter many aspects of cellular physiology, including levels of photosynthetic pigments and polyphosphate, DNA content, and the rate of translation. Cells unable to synthesize ppGpp display pronounced growth defects after exposure to darkness. The stringent response regulates expression of a number of genes in Synechococcus, including ribosomal hibernation promoting factor (hpf), which causes ribosomes to dimerize in the dark and may contribute to decreased translation. Although the metabolism of Synechococcus differentiates it from other model bacterial systems, the logic of the stringent response remains remarkably conserved, while at the same time having adapted to the unique stresses of the photosynthetic lifestyle. PMID:27486247

Parallel Architectures for Planetary Exploration Requirements (PAPER)

NASA Technical Reports Server (NTRS)

Cezzar, Ruknet; Sen, Ranjan K.

1989-01-01

The Parallel Architectures for Planetary Exploration Requirements (PAPER) project is essentially research oriented towards technology insertion issues for NASA's unmanned planetary probes. It was initiated to complement and augment the long-term efforts for space exploration with particular reference to NASA/LaRC's (NASA Langley Research Center) research needs for planetary exploration missions of the mid and late 1990s. The requirements for space missions as given in the somewhat dated Advanced Information Processing Systems (AIPS) requirements document are contrasted with the new requirements from JPL/Caltech involving sensor data capture and scene analysis. It is shown that more stringent requirements have arisen as a result of technological advancements. Two possible architectures, the AIPS Proof of Concept (POC) configuration and the MAX Fault-tolerant dataflow multiprocessor, were evaluated. The main observation was that the AIPS design is biased towards fault tolerance and may not be an ideal architecture for planetary and deep space probes due to high cost and complexity. The MAX concepts appears to be a promising candidate, except that more detailed information is required. The feasibility for adding neural computation capability to this architecture needs to be studied. Key impact issues for architectural design of computing systems meant for planetary missions were also identified.

Planning and response to Ebola virus disease: An integrated approach.

PubMed

Smith, Philip W; Boulter, Kathleen C; Hewlett, Angela L; Kratochvil, Christopher J; Beam, Elizabeth J; Gibbs, Shawn G; Lowe, John-Martin J; Schwedhelm, Michelle M

2015-05-01

The care of patients with Ebola virus disease (EVD) requires the application of critical care medicine principles under conditions of stringent infection control precautions. The care of patients with EVD requires a number of elements in terms of physical layout, personal protective apparel, and other equipment. Provision of care is demanding in terms of depth of staff and training. The key to safely providing such care is a system that brings many valuable skills to the table, and allows communication between these individuals. We present our approach to leadership structure and function--a variation of incident command--in providing care to 3 patients with EVD. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

A translational velocity command system for VTOL low speed flight

NASA Technical Reports Server (NTRS)

Merrick, V. K.

1982-01-01

A translational velocity flight controller, suitable for very low speed maneuvering, is described and its application to a large class of VTOL aircraft from jet lift to propeller driven types is analyzed. Estimates for the more critical lateral axis lead to the conclusion that the controller would provide a jet lift (high disk loading) VTOL aircraft with satisfactory "hands off" station keeping in operational conditions more stringent than any specified in current or projected requirements. It also seems likely that ducted fan or propeller driven (low disk loading) VTOL aircraft would have acceptable hovering handling qualities even in high turbulence, although in these conditions pilot intervention to maintain satisfactory station keeping would probably be required for landing in restricted areas.

Development of a 10 Ah, Prismatic, Lithium-Ion Cell for NASA/GSFC

NASA Technical Reports Server (NTRS)

Stein, Brian; Baker, John W.; George, Douglas S.; Isaacs, Nathan D.; Shah, Pinakin M.; Rao, Gopalakrishna M.; Day, John H. (Technical Monitor)

2001-01-01

MSA's 10 Ah Li-ion cell is a rugged design suitable for the stringent requirements of aerospace applications. Eighteen cells demonstrate consistent cycling performance over a wide range of rates and temperatures. The cell passes qualification requirements for vibration survivability technology improvements at MSA continue to enhance cell performance.

40 CFR 1039.625 - What requirements apply under the program for equipment-manufacturer flexibility?

Code of Federal Regulations, 2014 CFR

2014-07-01

... differences that justify your request. (vi) Describe your efforts to find and use other compliant engines, or... NONROAD COMPRESSION-IGNITION ENGINES Special Compliance Provisions § 1039.625 What requirements apply... manufacturers to produce equipment with engines that are subject to less stringent emission standards after the...

A Near-Optimal Distributed QoS Constrained Routing Algorithm for Multichannel Wireless Sensor Networks

PubMed Central

Lin, Frank Yeong-Sung; Hsiao, Chiu-Han; Yen, Hong-Hsu; Hsieh, Yu-Jen

2013-01-01

One of the important applications in Wireless Sensor Networks (WSNs) is video surveillance that includes the tasks of video data processing and transmission. Processing and transmission of image and video data in WSNs has attracted a lot of attention in recent years. This is known as Wireless Visual Sensor Networks (WVSNs). WVSNs are distributed intelligent systems for collecting image or video data with unique performance, complexity, and quality of service challenges. WVSNs consist of a large number of battery-powered and resource constrained camera nodes. End-to-end delay is a very important Quality of Service (QoS) metric for video surveillance application in WVSNs. How to meet the stringent delay QoS in resource constrained WVSNs is a challenging issue that requires novel distributed and collaborative routing strategies. This paper proposes a Near-Optimal Distributed QoS Constrained (NODQC) routing algorithm to achieve an end-to-end route with lower delay and higher throughput. A Lagrangian Relaxation (LR)-based routing metric that considers the “system perspective” and “user perspective” is proposed to determine the near-optimal routing paths that satisfy end-to-end delay constraints with high system throughput. The empirical results show that the NODQC routing algorithm outperforms others in terms of higher system throughput with lower average end-to-end delay and delay jitter. In this paper, for the first time, the algorithm shows how to meet the delay QoS and at the same time how to achieve higher system throughput in stringently resource constrained WVSNs.

Alignment telescope for Antares

NASA Astrophysics Data System (ADS)

Appert, Q. D.; Swann, T. A.; Ward, J. H.; Hardesty, C.; Wright, L.

The Antares Automatic Alignment System employs a specially designed telescope for alignment of its laser beamlines. There are two telescopes in the system, and since each telescope is a primary alignment reference, stringent boresight accuracy and stability over the focus range were required. Optical and mechanical designs, which meet this requirements as well as that of image quality over a wide wavelength band, are described. Special test techniques for initial assembly and alignment of the telescope are also presented. The telescope, which has a 180-mm aperture FK51-KZF2 type glass doublet objective, requires a boresight accuracy of 2.8 (SIGMA)rad at two focal lengths, and object distances between 11 meters and infinity. Travel of a smaller secondary doublet provides focus from 11 m to infinity with approximately 7.8 m effective focal length. By flipping in a third doublet, the effective focal length is reduced to 2.5 m. Telescope alignment was accomplished by using a rotary air bearing to establish an axis in front of the system and placing the focus of a Laser Unequal Path Interferometer (LUPI) at the image plane.

Alignment Telescope For Antares

NASA Astrophysics Data System (ADS)

Appert, Q. D.; Swann, T. A.; Ward, J. H.; Hardesty, C.; Wrignt, L.

1983-11-01

The Antares Automatic Alignment System employs a specially designed telescope for alignment of its laser beamlines. There are two telescopes in the system, and since eacn telescope is a primary alignment reference, stringent boresight accuracy and stability over the focus range were required. Optical and mechanical designs, which meet this requirement as well as that of image quality over a wide wavelength band, are described. Special test techniques for initial assembly and alignment of the telescope are also presented. The telescope, which has a 180-mm aperture FK51-KZF2 type glass doublet objective, requires a boresight accuracy of 2.8 prad at two focal lengths, and object distances between 11 meters and infinity. Travel of a smaller secondary doublet provides focus from 11 m to infinity with approximately 7.8 m effective focal length. By flipping in a third doublet, the effective focal length is reduced to 2.5 m. Telescope alignment was accomplished by using a rotary air bearing to establish an axis in front of the system and placing the focus of a Laser Unequal Path Interferometer (LUPI) at the image plane.

Turbomachinery Course

NASA Technical Reports Server (NTRS)

Stinson, Henry; Turner, James (Technical Monitor)

2002-01-01

In this viewgraph presentation, information and diagrams are provided on rocket engine turbopumps. These turbomachines are highly complex and have several unique features: (1) They are generally very high power density machines; (2) They experience high fluid dynamic loads; (3) They are exposed to severe thermal shocks in terms of rapid starts and stops and extremely high heat transfer coefficients; (4) They have stringent suction performance requirements to minimize tank weight; (5) Their working fluids significantly impact the design: oxidizers are generally explosive, they afford almost no lubrication for bearings and seals, some fuels can degrade material properties, cryogenics result in severe thermal gradients; (6) Their life requirements are short relative to other turbomachines in that there are hundreds of cycles and a few hours of operation for reusable systems. The design of rocket engine turbomachines is a systems engineering challenge because multiple engineering disciplines must be integrated to deal with issues pertaining to stress, structural dynamics, hydrodynamics, aerodynamics, thermodynamics, and materials and process selection.

New Concept for FES-Induced Movements

NASA Astrophysics Data System (ADS)

Ahmed, Mohammed; Huq, M. S.; Ibrahim, B. S. K. K.; Ahmed, Aisha; Ahmed, Zainab

2016-11-01

Functional Electrical Stimulation (FES) had become a viable option for movement restoration, therapy and rehabilitation in neurologically impaired subjects. Although the number of such subjects increase globally but only few orthosis devices combine with the technique are available and are costly. A factor resulting to this could be stringent requirement for such devices to have passed clinical acceptance. In that regard a new approach which utilize the patient wheelchair as support and also a novel control system to synchronize the stimulation such that the movement is accomplished safely was proposed. It is expected to improve well-being, social integration, independence, cost, and healthcare delivery.

Scanning mirror for infrared sensors

NASA Technical Reports Server (NTRS)

Anderson, R. H.; Bernstein, S. B.

1972-01-01

A high resolution, long life angle-encoded scanning mirror, built for application in an infrared attitude sensor, is described. The mirror uses a Moire' fringe type optical encoder and unique torsion bar suspension together with a magnetic drive to meet stringent operational and environmental requirements at a minimum weight and with minimum power consumption. Details of the specifications, design, and construction are presented with an analysis of the mirror suspension that allows accurate prediction of performance. The emphasis is on mechanical design considerations, and brief discussions are included on the encoder and magnetic drive to provide a complete view of the mirror system and its capabilities.

Preservation of Gaussian state entanglement in a quantum beat laser by reservoir engineering

NASA Astrophysics Data System (ADS)

Qurban, Misbah; Islam, Rameez ul; Ge, Guo-Qin; Ikram, Manzoor

2018-04-01

Quantum beat lasers have been considered as sources of entangled radiation in continuous variables such as Gaussian states. In order to preserve entanglement and to minimize entanglement degradation due to the system’s interaction with the surrounding environment, we propose to engineer environment modes through insertion of another system in between the laser resonator and the environment. This makes the environment surrounding the two-mode laser a structured reservoir. It not only enhances the entanglement among two modes of the laser but also preserves the entanglement for sufficiently longer times, a stringent requirement for quantum information processing tasks.

Challenges in Aeropropulsion

NASA Technical Reports Server (NTRS)

Campbell, Donald C.

1995-01-01

Aeropropulsion technologies must progress to satisfy increasingly stringent global environmental requirements with economically viable air transportation systems. In this paper, key propulsion technologies to meet future needs are identified and the associated challenges are briefly discussed. Also discussed are NASA's vision, NASA's changing role in meeting today's challenge of a shrinking research budget, and propulsion technology impacts on the environment and air transport economics. Critical aeropropulsion technology drivers are identified and their impact evaluated. The aviation industry is critical to the nation's economy, job creation, and national security. NASA's advanced aeropropulsion technology programs and their relation to the aviation industry are discussed.

The Further Development of Heat-Resistant Materials for Aircraft Engines

NASA Technical Reports Server (NTRS)

Bollenrath, Franz

1946-01-01

The present report deals with the problems involved in the greater utilization and development of aircraft engine materials, and specifically; piston materials, cylinder heads, exhaust valves, and exhaust gas turbine blading. The blades of the exhaust gas turbine are likely to be the highest stressed components of modern power plants from a thermal-mechanical and chemical standpoint, even though the requirements on exhaust valves of engines with gasoline injection are in general no less stringent. For the fire plate in Diesel engines the specifications for mechanical strength and design are not so stringent, and the question of heat resistance, which under these circumstances is easier obtainable, predominates.

76 FR 57515 - Energy Conservation Program: Energy Conservation Standards for Residential Refrigerators...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-15

...The Energy Policy and Conservation Act (EPCA) prescribes energy conservation standards for various consumer products and commercial and industrial equipment, including refrigerators, refrigerator-freezers, and freezers. EPCA also requires the U.S. Department of Energy (DOE) to determine if more stringent, amended standards for these products are technologically feasible and economically justified, and would save a significant amount of energy. In this final rule, DOE is adopting more stringent energy conservation standards for refrigerators, refrigerator-freezers, and freezers. It has determined that the amended energy conservation standards for these products would result in the significant conservation of energy and are technologically feasible and economically justified.

Welding and joining techniques.

PubMed

Chipperfield, F A; Dunkerton, S B

2001-05-01

There is a welding solution for most applications. As products must meet more stringent requirements or require more flexible processes to aid design or reduce cost, further improvements or totally new processes are likely to be developed. Quality control aspects are also becoming more important to meet regulation, and monitoring and control of welding processes and the standardised testing of joints will meet some if not all of these requirements.

Bee guide to complying with the Safe Drinking Water Act. Final report

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

Garland, J.G.; Acker, A.M.

This report provides current information on the Safe Drinking Water Act and recent amendments. The report describes the evolution of the Safe Drinking Water Act and the responsibilities of base personnel involved in compliance with the Act. It also describes the monitoring requirements, analytical requirements, best available technology for controlling contaminants, and public notification requirements for regulated contaminants. The appendixes include proposed contaminants and state water quality agencies. Each Air Force public water distribution system (PWDS) must comply with the SDWA, and the National Primary Drinking Water Regulations (NPDWRs). In the United States and its territories, the provisions of themore » SDWA and the NPDWRs are enforced by the states except in the few instances in which the state has not been delegated primary enforcement responsibility (primacy) by the EPA. States that have primacy may establish drinking water regulations, monitoring schedules, and reporting requirements more stringent than, or in addition to, those in the NPDWRs. Air Force public water systems in these states are required to comply with these additional requirements as well as federal enforcement actions as carried out by the EPA Regional Office.« less

Active stability augmentation of large space structures: A stochastic control problem

NASA Technical Reports Server (NTRS)

Balakrishnan, A. V.

1987-01-01

A problem in SCOLE is that of slewing an offset antenna on a long flexible beam-like truss attached to the space shuttle, with rather stringent pointing accuracy requirements. The relevant methodology aspects in robust feedback-control design for stability augmentation of the beam using on-board sensors is examined. It is framed as a stochastic control problem, boundary control of a distributed parameter system described by partial differential equations. While the framework is mathematical, the emphasis is still on an engineering solution. An abstract mathematical formulation is developed as a nonlinear wave equation in a Hilbert space. That the system is controllable is shown and a feedback control law that is robust in the sense that it does not require quantitative knowledge of system parameters is developed. The stochastic control problem that arises in instrumenting this law using appropriate sensors is treated. Using an engineering first approximation which is valid for small damping, formulas for optimal choice of the control gain are developed.

Appropriate technology for domestic wastewater management in under-resourced regions of the world

NASA Astrophysics Data System (ADS)

Oladoja, Nurudeen Abiola

2017-11-01

Centralized wastewater management system is the modern day waste management practice, but the high cost and stringent requirements for the construction and operation have made it less attractive in the under-resourced regions of the world. Considering these challenges, the use of decentralized wastewater management system, on-site treatment system, as an appropriate technology for domestic wastewater treatment is hereby advocated. Adopting this technology helps save money, protects home owners' investment, promotes better watershed management, offers an appropriate solution for low-density communities, provides suitable alternatives for varying site conditions and furnishes effective solutions for ecologically sensitive areas. In the light of this, an overview of the on-site treatment scheme, at the laboratory scale, pilot study stage, and field trials was conducted to highlight the operational principles' strength and shortcomings of the scheme. The operational requirements for the establishing and operation of the scheme and best management practice to enhance the performance and sustenance were proffered.

The detector calibration system for the CUORE cryogenic bolometer array

DOE PAGES

Cushman, Jeremy S.; Dally, Adam; Davis, Christopher J.; ...

2016-11-14

The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale cryogenic experiment designed to search for neutrinoless double-beta decay of 130Te and other rare events. The CUORE detector consists of 988 TeO 2 bolometers operated underground at 10 mK in a dilution refrigerator at the Laboratori Nazionali del Gran Sasso. Candidate events are identified through a precise measurement of their energy. The absolute energy response of the detectors is established by the regular calibration of each individual bolometer using gamma sources. The close-packed configuration of the CUORE bolometer array combined with the extensive shielding surrounding the detectors requires themore » placement of calibration sources within the array itself. The CUORE Detector Calibration System is designed to insert radioactive sources into and remove them from the cryostat while respecting the stringent heat load, radiopurity, and operational requirements of the experiment. In conclusion, this paper describes the design, commissioning, and performance of this novel source calibration deployment system for ultra-low-temperature environments.« less

RT-MATRIX: Measuring Total Organic Carbon by Photocatalytic Oxidation of Volatile Organic Compounds

NASA Technical Reports Server (NTRS)

2008-01-01

Volatile organic compounds (VOCs) inevitably accumulate in enclosed habitats such as the International Space Station and the Crew Exploration Vehicle (CEV) as a result of human metabolism, material off-gassing, and leaking equipment. Some VOCs can negatively affect the quality of the crew's life, health, and performance; and consequently, the success of the mission. Air quality must be closely monitored to ensure a safe living and working environment. Currently, there is no reliable air quality monitoring system that meets NASA's stringent requirements for power, mass, volume, or performance. The ultimate objective of the project -- the development of a Real-Time, Miniaturized, Autonomous Total Risk Indicator System (RT.MATRIX).is to provide a portable, dual-function sensing system that simultaneously determines total organic carbon (TOC) and individual contaminants in air streams.

Programming Models for Concurrency and Real-Time

NASA Astrophysics Data System (ADS)

Vitek, Jan

Modern real-time applications are increasingly large, complex and concurrent systems which must meet stringent performance and predictability requirements. Programming those systems require fundamental advances in programming languages and runtime systems. This talk presents our work on Flexotasks, a programming model for concurrent, real-time systems inspired by stream-processing and concurrent active objects. Some of the key innovations in Flexotasks are that it support both real-time garbage collection and region-based memory with an ownership type system for static safety. Communication between tasks is performed by channels with a linear type discipline to avoid copying messages, and by a non-blocking transactional memory facility. We have evaluated our model empirically within two distinct implementations, one based on Purdue’s Ovm research virtual machine framework and the other on Websphere, IBM’s production real-time virtual machine. We have written a number of small programs, as well as a 30 KLOC avionics collision detector application. We show that Flexotasks are capable of executing periodic threads at 10 KHz with a standard deviation of 1.2us and have performance competitive with hand coded C programs.

Ver-i-Fus: an integrated access control and information monitoring and management system

NASA Astrophysics Data System (ADS)

Thomopoulos, Stelios C.; Reisman, James G.; Papelis, Yiannis E.

1997-01-01

This paper describes the Ver-i-Fus Integrated Access Control and Information Monitoring and Management (IAC-I2M) system that INTELNET Inc. has developed. The Ver-i-Fus IAC-I2M system has been designed to meet the most stringent security and information monitoring requirements while allowing two- way communication between the user and the system. The systems offers a flexible interface that permits to integrate practically any sensing device, or combination of sensing devices, including a live-scan fingerprint reader, thus providing biometrics verification for enhanced security. Different configurations of the system provide solutions to different sets of access control problems. The re-configurable hardware interface, tied together with biometrics verification and a flexible interface that allows to integrate Ver-i-Fus with an MIS, provide an integrated solution to security, time and attendance, labor monitoring, production monitoring, and payroll applications.

School Meal Programs: Revenue and Expense Information from Selected States. Report to Congressional Requesters.

ERIC Educational Resources Information Center

Bellis, David D.

In school year 1996-97, the Department of Agriculture instituted more stringent requirements for the nutritional content of school meals. The General Accounting Office was asked to study school food-service revenues and expenses and how they had changed since the requirements went into effect. This report contains information of the sources of…

Contaminant levels, source strengths, and ventilation rates in California retail stores.

PubMed

Chan, W R; Cohn, S; Sidheswaran, M; Sullivan, D P; Fisk, W J

2015-08-01

This field study measured ventilation rates and indoor air quality in 21 visits to retail stores in California. Three types of stores, such as grocery, furniture/hardware stores, and apparel, were sampled. Ventilation rates measured using a tracer gas decay method exceeded the minimum requirement of California's Title 24 Standard in all but one store. Concentrations of volatile organic compounds (VOCs), ozone, and carbon dioxide measured indoors and outdoors were analyzed. Even though there was adequate ventilation according to standard, concentrations of formaldehyde and acetaldehyde exceeded the most stringent chronic health guidelines in many of the sampled stores. The whole-building emission rates of VOCs were estimated from the measured ventilation rates and the concentrations measured indoor and outdoor. Estimated formaldehyde emission rates suggest that retail stores would need to ventilate at levels far exceeding the current Title 24 requirement to lower indoor concentrations below California's stringent formaldehyde reference level. Given the high costs of providing ventilation, effective source control is an attractive alternative. Field measurements suggest that California retail stores were well ventilated relative to the minimum ventilation rate requirement specified in the Building Energy Efficiency Standards Title 24. Concentrations of formaldehyde found in retail stores were low relative to levels found in homes but exceeded the most stringent chronic health guideline. Looking ahead, California is mandating zero energy commercial buildings by 2030. To reduce the energy use from building ventilation while maintaining or even lowering formaldehyde in retail stores, effective formaldehyde source control measures are vitally important. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Experimental study of precisely selected evaporation chains in the decay of excited 25Mg

NASA Astrophysics Data System (ADS)

Camaiani, A.; Casini, G.; Morelli, L.; Barlini, S.; Piantelli, S.; Baiocco, G.; Bini, M.; Bruno, M.; Buccola, A.; Cinausero, M.; Cicerchia, M.; D'Agostino, M.; Degelier, M.; Fabris, D.; Frosin, C.; Gramegna, F.; Gulminelli, F.; Mantovani, G.; Marchi, T.; Olmi, A.; Ottanelli, P.; Pasquali, G.; Pastore, G.; Valdré, S.; Verde, G.

2018-04-01

The reaction 12C+13C at 95 MeV bombarding energy is studied using the Garfield + Ring Counter apparatus located at the INFN Laboratori Nazionali di Legnaro. In this paper we want to investigate the de-excitation of 25Mg aiming both at a new stringent test of the statistical description of nuclear decay and a direct comparison with the decay of the system 24Mg formed through 12C+12C reactions previously studied. Thanks to the large acceptance of the detector and to its good fragment identification capabilities, we could apply stringent selections on fusion-evaporation events, requiring their completeness in charge. The main decay features of the evaporation residues and of the emitted light particles are overall well described by a pure statistical model; however, as for the case of the previously studied 24Mg, we observed some deviations in the branching ratios, in particular for those chains involving only the evaporation of α particles. From this point of view the behavior of the 24Mg and 25Mg decay cases appear to be rather similar. An attempt to obtain a full mass balance even without neutron detection is also discussed.

Technology Requirements for a Square Meter, Arcsecond Resolution Telescope for X-Rays: The SMART-X Mission

NASA Technical Reports Server (NTRS)

Schwartz, Daniel A.; Allured, Ryan; Bookbinder, Jay A.; Cotroneo, Vincenzo; Forman, William R.; Freeman, Mark D.; McMuldroch, Stuart; Reid, Paul B.; Tananbaum, Harvey; Vikhlinin, Alexey A.;

The NOνA Module Factory Quality Assurance System

NASA Astrophysics Data System (ADS)

Smith, Alex; the NOνA Collaboration

The NOνA experiment will measure neutrino oscillations using a long-baseline beam, a ∼220-ton near detector and a ∼14-kiloton far detector. Production of ∼12500 modules to build these detectors is an industrial scale operation requiring careful quality assurance to meet the stringent technical specifications. Unlike a typical industrial operation, this project will use primarily a part time labor force of ∼200 University of Minnesota undergraduate students managed by a small team of full time employees. The quality assurance system is involved in nearly every aspect of the production: assembly, scheduling, training, payroll, materials, machine maintenance, test data, and safety compliance. The quality assurance data collected during the assembly process allows us to quickly identify and correct any problems that arise.

The high Beta cryo-modules and the associated cryogenic system for the HIE-ISOLDE upgrade at CERN

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

Delruelle, N.; Leclercq, Y.; Pirotte, O.

2014-01-29

The major upgrade of the energy and intensity of the existing ISOLDE and REX-ISOLDE radioactive ion beam facilities at CERN requires the replacement of most of the existing ISOLDE post-acceleration equipment by a superconducting linac based on quarter-wave resonators housed together with superconducting solenoids in a series of four high-β and two low-β cryo-modules. As well as providing optimum conditions for physics, the cryo-modules need to function under stringent vacuum and cryogenic conditions. We present the detail design and expected cryogenic performance of the high- β cryo-module together with the cryogenic supply and distribution system destined to service the completemore » superconducting linac.« less

A Viking satellite orbit trim strategy

NASA Technical Reports Server (NTRS)

Hintz, G. R.

1971-01-01

One strategy is submitted for meeting the varied and stringent requirements of the Viking Project on the control of the satellite orbit to obtain reconnaissance and to prepare for lander release. To satisfy these requirements, different orbit trim maneuver strategies were developed for two typical Viking missions. In addition, a summary of recent numerical results is included to show that this strategy satisfies the mission requirements which have been identified.

Analysis of QoS Requirements for e-Health Services and Mapping to Evolved Packet System QoS Classes

PubMed Central

Skorin-Kapov, Lea; Matijasevic, Maja

2010-01-01

E-Health services comprise a broad range of healthcare services delivered by using information and communication technology. In order to support existing as well as emerging e-Health services over converged next generation network (NGN) architectures, there is a need for network QoS control mechanisms that meet the often stringent requirements of such services. In this paper, we evaluate the QoS support for e-Health services in the context of the Evolved Packet System (EPS), specified by the Third Generation Partnership Project (3GPP) as a multi-access all-IP NGN. We classify heterogeneous e-Health services based on context and network QoS requirements and propose a mapping to existing 3GPP QoS Class Identifiers (QCIs) that serve as a basis for the class-based QoS concept of the EPS. The proposed mapping aims to provide network operators with guidelines for meeting heterogeneous e-Health service requirements. As an example, we present the QoS requirements for a prototype e-Health service supporting tele-consultation between a patient and a doctor and illustrate the use of the proposed mapping to QCIs in standardized QoS control procedures. PMID:20976301

Passive isolation/damping system for the Hubble space telescope reaction wheels

NASA Technical Reports Server (NTRS)

Hasha, Martin D.

1987-01-01

NASA's Hubble Space Telescope contain large, diffraction limited optics with extraordinary resolution and performance for surpassing existing observatories. The need to reduce structural borne vibration and resultant optical jitter from critical Pointing Control System components, Reaction Wheels, prompted the feasibility investigation and eventual development of a passive isolation system. Alternative design concepts considered were required to meet a host of stringent specifications and pass rigid tests to be successfully verified and integrated into the already built flight vehicle. The final design employs multiple arrays of fluid damped springs that attenuate over a wide spectrum, while confining newly introduced resonances to benign regions of vehicle dynamic response. Overall jitter improvement of roughly a factor of 2 to 3 is attained with this system. The basis, evolution, and performance of the isolation system, specifically discussing design concepts considered, optimization studies, development lessons learned, innovative features, and analytical and ground test verified results are presented.

Performance and Life Tests of a Regenerative Blower for EVA Suit Ventilation

NASA Technical Reports Server (NTRS)

Izenson, Mike; Chen, Weibo; Paul, Heather L.; Jennings, Mallory A.

2011-01-01

Ventilation fans for future space suits must meet demanding performance specifications, satisfy stringent safety requirements for operation in an oxygen atmosphere, and be able to increase output to operate in buddy mode. A regenerative blower is an attractive choice due to its ability to meet these requirements at low operating speed. This paper describes progress in the development and testing of a regenerative blower designed to meet requirements for ventilation subsystems in a future space suit Portable Life Support Systems (PLSS). The blower assembly includes a custom-designed motor that has significantly improved in efficiency during this development effort. The blower was tested at both nominal and buddy mode operating points and head/flow performance and power consumption were measured. The blower was operated for over 1000 hours to demonstrate safe operation in an oxygen test loop at prototypical pressures. In addition, the blower demonstrated operation with the introduction of simulated lunar dust.

Augmenting the Genetic Toolbox for Sulfolobus islandicus with a Stringent Positive Selectable Marker for Agmatine Prototrophy

PubMed Central

Cooper, Tara E.; Krause, David J.

2013-01-01

Sulfolobus species have become the model organisms for studying the unique biology of the crenarchaeal division of the archaeal domain. In particular, Sulfolobus islandicus provides a powerful opportunity to explore natural variation via experimental functional genomics. To support these efforts, we further expanded genetic tools for S. islandicus by developing a stringent positive selection for agmatine prototrophs in strains in which the argD gene, encoding arginine decarboxylase, has been deleted. Strains with deletions in argD were shown to be auxotrophic for agmatine even in nutrient-rich medium, but growth could be restored by either supplementation of exogenous agmatine or reintroduction of a functional copy of the argD gene from S. solfataricus P2 into the ΔargD host. Using this stringent selection, a robust targeted gene knockout system was established via an improved next generation of the MID (marker insertion and unmarked target gene deletion) method. Application of this novel system was validated by targeted knockout of the upsEF genes involved in UV-inducible cell aggregation formation. PMID:23835176

Advanced model-based FDIR techniques for aerospace systems: Today challenges and opportunities

NASA Astrophysics Data System (ADS)

Zolghadri, Ali

2012-08-01

This paper discusses some trends and recent advances in model-based Fault Detection, Isolation and Recovery (FDIR) for aerospace systems. The FDIR challenges range from pre-design and design stages for upcoming and new programs, to improvement of the performance of in-service flying systems. For space missions, optimization of flight conditions and safe operation is intrinsically related to GNC (Guidance, Navigation & Control) system of the spacecraft and includes sensors and actuators monitoring. Many future space missions will require autonomous proximity operations including fault diagnosis and the subsequent control and guidance recovery actions. For upcoming and future aircraft, one of the main issues is how early and robust diagnosis of some small and subtle faults could contribute to the overall optimization of aircraft design. This issue would be an important factor for anticipating the more and more stringent requirements which would come in force for future environmentally-friendlier programs. The paper underlines the reasons for a widening gap between the advanced scientific FDIR methods being developed by the academic community and technological solutions demanded by the aerospace industry.

40 CFR 131.4 - State authority.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS... reviewing, establishing, and revising water quality standards. As recognized by section 510 of the Clean Water Act, States may develop water quality standards more stringent than required by this regulation...

40 CFR 63.11118 - Requirements for facilities with monthly throughput of 100,000 gallons of gasoline or more.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Management Practices § 63.11118 Requirements for facilities with monthly throughput of 100,000 gallons of...)(1) or paragraph (b)(2) of this section. (1) Each management practice in Table 1 to this subpart that...) Operates using management practices at least as stringent as those in Table 1 to this subpart. (ii) Your...

Colorado River Sewer System Joint Venture to Upgrade Wastewater System

EPA Pesticide Factsheets

SAN FRANCISCO -Today, the Colorado River Sewer System Joint Venture, located in Parker, Ariz. entered into an agreement with the EPA to upgrade their wastewater treatment system to meet stringent water quality standards. The cost of the upgrade is ap

Dynamic Resource Allocation for IEEE802.16e

NASA Astrophysics Data System (ADS)

Nascimento, Alberto; Rodriguez, Jonathan

Mobile communications has witnessed an exponential increase in the amount of users, services and applications. New high bandwidth consuming applications are targeted for B3G networks raising more stringent requirements for Dynamic Resource Allocation (DRA) architectures and packet schedulers that must be spectrum efficient and deliver QoS for heterogeneous applications and services. In this paper we propose a new cross layer-based architecture framework embedded in a newly designed DRA architecture for the Mobile WiMAX standard. System level simulation results show that the proposed architecture can be considered a viable candidate solution for supporting mixed services in a cost-effective manner in contrast to existing approaches.

MAP Propulsion System Thermal Design

NASA Technical Reports Server (NTRS)

Mosier, Carol L.

2003-01-01

The propulsion system of the Microwave Anisotropy Probe (MAP) had stringent requirements that made the thermal design unique. To meet instrument stability requirements the system had to be designed to keep temperatures of all components within acceptable limits without heater cycling. Although the spacecraft remains at a fixed 22 sun angle at L2, the variations in solar constant, property degradation, and bus voltage range all significantly affect the temperature. Large portions of the fuel lines are external to the structure and all components are mounted to non-conductive composite structure. These two facts made the sensitivity to the MLI effective emissivity and bus temperature very high. Approximately two years prior to launch the propulsion system was redesigned to meet MAP requirements. The new design utilized hardware that was already installed in order to meet schedule constraints. The spacecraft design and the thermal requirements were changed to compensate for inadequacies of the existing hardware. The propulsion system consists of fuel lines, fill and drain lines/valve, eight thrusters, a HXCM, and a propulsion tank. A voltage regulator was added to keep critical components within limits. Software was developed to control the operational heaters. Trim resistors were put in series with each operational heater circuits and the tank survival heater. A highly sophisticated test program, which included real time model correlation, was developed to determine trim resistors sizes. These trim resistors were installed during a chamber break and verified during thermal balance testing.

Contamination Control Assessment of the World's Largest Space Environment Simulation Chamber

NASA Technical Reports Server (NTRS)

Snyder, Aaron; Henry, Michael W.; Grisnik, Stanley P.; Sinclair, Stephen M.

2012-01-01

The Space Power Facility s thermal vacuum test chamber is the largest chamber in the world capable of providing an environment for space simulation. To improve performance and meet stringent requirements of a wide customer base, significant modifications were made to the vacuum chamber. These include major changes to the vacuum system and numerous enhancements to the chamber s unique polar crane, with a goal of providing high cleanliness levels. The significance of these changes and modifications are discussed in this paper. In addition, the composition and arrangement of the pumping system and its impact on molecular back-streaming are discussed in detail. Molecular contamination measurements obtained with a TQCM and witness wafers during two recent integrated system tests of the chamber are presented and discussed. Finally, a concluding remarks section is presented.

Differential detection of Gaussian MSK in a mobile radio environment

NASA Technical Reports Server (NTRS)

Simon, M. K.; Wang, C. C.

1984-01-01

Minimum shift keying with Gaussian shaped transmit pulses is a strong candidate for a modulation technique that satisfies the stringent out-of-band radiated power requirements of the mobil radio application. Numerous studies and field experiments have been conducted by the Japanese on urban and suburban mobile radio channels with systems employing Gaussian minimum-shift keying (GMSK) transmission and differentially coherent reception. A comprehensive analytical treatment is presented of the performance of such systems emphasizing the important trade-offs among the various system design parameters such as transmit and receiver filter bandwidths and detection threshold level. It is shown that two-bit differential detection of GMSK is capable of offering far superior performance to the more conventional one-bit detection method both in the presence of an additive Gaussian noise background and Rician fading.

Differential detection of Gaussian MSK in a mobile radio environment

NASA Astrophysics Data System (ADS)

Simon, M. K.; Wang, C. C.

1984-11-01

Minimum shift keying with Gaussian shaped transmit pulses is a strong candidate for a modulation technique that satisfies the stringent out-of-band radiated power requirements of the mobil radio application. Numerous studies and field experiments have been conducted by the Japanese on urban and suburban mobile radio channels with systems employing Gaussian minimum-shift keying (GMSK) transmission and differentially coherent reception. A comprehensive analytical treatment is presented of the performance of such systems emphasizing the important trade-offs among the various system design parameters such as transmit and receiver filter bandwidths and detection threshold level. It is shown that two-bit differential detection of GMSK is capable of offering far superior performance to the more conventional one-bit detection method both in the presence of an additive Gaussian noise background and Rician fading.

Investigation of material improvements to mitigate the abrasive wear mechanism of concrete crosstie rail seat deterioration (RSD).

DOT National Transportation Integrated Search

2014-11-01

To meet the increasingly stringent design and performance requirements due to increasing cumulative : gross tonnages from heavy-haul freight operations, along with increased high-speed inter-city passenger : rail development, improvements in concrete...

Deriving protection thresholds for threatened and endangered species potentially exposed to pesticides

EPA Science Inventory

The Endangered Species Act requires specific and stringent protection to threatened and endangered species and their critical habitat. Therefore, protective methods for risk assessment for such species are needed. Species sensitivity distributions (SSDs) are a common tool used fo...

76 FR 20556 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-13

... stringent in their floodplain management requirements. The community may at any time enact stricter... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA...: Federal Emergency Management Agency, DHS. ACTION: Interim rule. SUMMARY: This interim rule lists...

76 FR 43601 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-21

... stringent in their floodplain management requirements. The community may at any time enact stricter... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA...: Federal Emergency Management Agency, DHS. ACTION: Interim rule. SUMMARY: This interim rule lists...

Cyber Safety and Security for Reduced Crew Operations (RCO)

NASA Technical Reports Server (NTRS)

Driscoll, Kevin R.; Roy, Aloke; Ponchak, Denise S.; Downey, Alan N.

2017-01-01

NASA and the Aviation Industry is looking into reduced crew operations (RCO) that would cut today's required two-person flight crews down to a single pilot with support from ground-based crews. Shared responsibility across air and ground personnel will require highly reliable and secure data communication and supporting automation, which will be safety-critical for passenger and cargo aircraft. This paper looks at the different types and degrees of authority delegation given from the air to the ground and the ramifications of each, including the safety and security hazards introduced, the mitigation mechanisms for these hazards, and other demands on an RCO system architecture which would be highly invasive into (almost) all safety-critical avionics. The adjacent fields of unmanned aerial systems and autonomous ground vehicles are viewed to find problems that RCO may face and related aviation accident scenarios are described. The paper explores possible data communication architectures to meet stringent performance and information security (INFOSEC) requirements of RCO. Subsequently, potential challenges for RCO data communication authentication, encryption and non-repudiation are identified.

Review of current interest and research in water hyacinth-based wastewater treatment

NASA Technical Reports Server (NTRS)

Markarian, R. K.; Balon, J. E.; Robinson, A. C.

1977-01-01

The status of activity in the user community for water hyacinth-based wastewater treatment was evaluated. The principal technique used was that of interviewing people who either (1) were known to be engaged in hyacinth research or development or (2) had made inquiry to NASA about hyacinth systems. About 40 non-research organizations and a similar number of research organizations were contacted. As a result of the interviews and a review of the relevant literature, it was concluded that hyacinth systems have the potential for providing a lower cost way for small cities to meet increasingly stringent effluent requirements. A limited amount of full-scale demonstration of hyacinth systems has been carried out during the past two years, but the yield of design data has been small. Several organizations are currently planning construction of experimental full-scale hyacinth-based wastewater treatment systems during 1977-1978.

Power Management Integrated Circuit for Indoor Photovoltaic Energy Harvesting System

NASA Astrophysics Data System (ADS)

Jain, Vipul

In today's world, power dissipation is a main concern for battery operated mobile devices. Key design decisions are being governed by power rather than area/delay because power requirements are growing more stringent every year. Hence, a hybrid power management system is proposed, which uses both a solar panel to harvest energy from indoor lighting and a battery to power the load. The system tracks the maximum power point of the solar panel and regulates the battery and microcontroller output load voltages through the use of an on-chip switched-capacitor DC-DC converter. System performance is verified through simulation at the 180nm technology node and is made to be integrated on-chip with 0.25 second startup time, 79% efficiency, --8/+14% ripple on the load, an average 1micro A of quiescent current (3.7micro W of power) and total on-chip area of 1.8mm2 .

Dual Regulation of Bacillus subtilis kinB Gene Encoding a Sporulation Trigger by SinR through Transcription Repression and Positive Stringent Transcription Control.

PubMed

Fujita, Yasutaro; Ogura, Mitsuo; Nii, Satomi; Hirooka, Kazutake

2017-01-01

It is known that transcription of kinB encoding a trigger for Bacillus subtilis sporulation is under repression by SinR, a master repressor of biofilm formation, and under positive stringent transcription control depending on the adenine species at the transcription initiation nucleotide (nt). Deletion and base substitution analyses of the kinB promoter (P kinB ) region using lacZ fusions indicated that either a 5-nt deletion (Δ5, nt -61/-57, +1 is the transcription initiation nt) or the substitution of G at nt -45 with A (G-45A) relieved kinB repression. Thus, we found a pair of SinR-binding consensus sequences (GTTCTYT; Y is T or C) in an inverted orientation (SinR-1) between nt -57/-42, which is most likely a SinR-binding site for kinB repression. This relief from SinR repression likely requires SinI, an antagonist of SinR. Surprisingly, we found that SinR is essential for positive stringent transcription control of P kinB . Electrophoretic mobility shift assay (EMSA) analysis indicated that SinR bound not only to SinR-1 but also to SinR-2 (nt -29/-8) consisting of another pair of SinR consensus sequences in a tandem repeat arrangement; the two sequences partially overlap the '-35' and '-10' regions of P kinB . Introduction of base substitutions (T-27C C-26T) in the upstream consensus sequence of SinR-2 affected positive stringent transcription control of P kinB , suggesting that SinR binding to SinR-2 likely causes this positive control. EMSA also implied that RNA polymerase and SinR are possibly bound together to SinR-2 to form a transcription initiation complex for kinB transcription. Thus, it was suggested in this work that derepression of kinB from SinR repression by SinI induced by Spo0A∼P and occurrence of SinR-dependent positive stringent transcription control of kinB might induce effective sporulation cooperatively, implying an intimate interplay by stringent response, sporulation, and biofilm formation.

Reliability of unstable periodic orbit based control strategies in biological systems.

PubMed

Mishra, Nagender; Hasse, Maria; Biswal, B; Singh, Harinder P

2015-04-01

Presence of recurrent and statistically significant unstable periodic orbits (UPOs) in time series obtained from biological systems is now routinely used as evidence for low dimensional chaos. Extracting accurate dynamical information from the detected UPO trajectories is vital for successful control strategies that either aim to stabilize the system near the fixed point or steer the system away from the periodic orbits. A hybrid UPO detection method from return maps that combines topological recurrence criterion, matrix fit algorithm, and stringent criterion for fixed point location gives accurate and statistically significant UPOs even in the presence of significant noise. Geometry of the return map, frequency of UPOs visiting the same trajectory, length of the data set, strength of the noise, and degree of nonstationarity affect the efficacy of the proposed method. Results suggest that establishing determinism from unambiguous UPO detection is often possible in short data sets with significant noise, but derived dynamical properties are rarely accurate and adequate for controlling the dynamics around these UPOs. A repeat chaos control experiment on epileptic hippocampal slices through more stringent control strategy and adaptive UPO tracking is reinterpreted in this context through simulation of similar control experiments on an analogous but stochastic computer model of epileptic brain slices. Reproduction of equivalent results suggests that far more stringent criteria are needed for linking apparent success of control in such experiments with possible determinism in the underlying dynamics.

Reliability of unstable periodic orbit based control strategies in biological systems

NASA Astrophysics Data System (ADS)

Mishra, Nagender; Hasse, Maria; Biswal, B.; Singh, Harinder P.

2015-04-01

Presence of recurrent and statistically significant unstable periodic orbits (UPOs) in time series obtained from biological systems is now routinely used as evidence for low dimensional chaos. Extracting accurate dynamical information from the detected UPO trajectories is vital for successful control strategies that either aim to stabilize the system near the fixed point or steer the system away from the periodic orbits. A hybrid UPO detection method from return maps that combines topological recurrence criterion, matrix fit algorithm, and stringent criterion for fixed point location gives accurate and statistically significant UPOs even in the presence of significant noise. Geometry of the return map, frequency of UPOs visiting the same trajectory, length of the data set, strength of the noise, and degree of nonstationarity affect the efficacy of the proposed method. Results suggest that establishing determinism from unambiguous UPO detection is often possible in short data sets with significant noise, but derived dynamical properties are rarely accurate and adequate for controlling the dynamics around these UPOs. A repeat chaos control experiment on epileptic hippocampal slices through more stringent control strategy and adaptive UPO tracking is reinterpreted in this context through simulation of similar control experiments on an analogous but stochastic computer model of epileptic brain slices. Reproduction of equivalent results suggests that far more stringent criteria are needed for linking apparent success of control in such experiments with possible determinism in the underlying dynamics.

Spacecraft Antennas

NASA Technical Reports Server (NTRS)

Jamnejad, Vahraz; Manshadi, Farzin; Rahmat-Samii, Yahya; Cramer, Paul

1990-01-01

Some of the various categories of issues that must be considered in the selection and design of spacecraft antennas for a Personal Access Satellite System (PASS) are addressed, and parametric studies for some of the antenna concepts to help the system designer in making the most appropriate antenna choice with regards to weight, size, and complexity, etc. are provided. The question of appropriate polarization for the spacecraft as well as for the User Terminal Antenna required particular attention and was studied in some depth. Circular polarization seems to be the favored outcome of this study. Another problem that has generally been a complicating factor in designing the multiple beam reflector antennas, is the type of feeds (single vs. multiple element and overlapping vs. non-overlapping clusters) needed for generating the beams. This choice is dependent on certain system design factors, such as the required frequency reuse, acceptable interbeam isolation, antenna efficiency, number of beams scanned, and beam-forming network (BFN) complexity. This issue is partially addressed, but is not completely resolved. Indications are that it may be possible to use relatively simple non-overlapping clusters of only a few elements, unless a large frequency reuse and very stringent isolation levels are required.

Ultra Low Outgassing silicone performance in a simulated space ionizing radiation environment

NASA Astrophysics Data System (ADS)

Velderrain, M.; Malave, V.; Taylor, E. W.

2010-09-01

The improvement of silicone-based materials used in space and aerospace environments has garnered much attention for several decades. Most recently, an Ultra Low Outgassing™ silicone incorporating innovative reinforcing and functional fillers has shown that silicone elastomers with unique and specific properties can be developed to meet applications requiring stringent outgassing requirements. This paper will report on the next crucial step in qualifying these materials for spacecraft applications requiring chemical and physical stability in the presence of ionizing radiation. As a first step in this process, selected materials were irradiated with Co-60 gamma-rays to simulate the total dose received in near- Earth orbits. The paper will present pre-and post-irradiation response data of Ultra Low Outgassing silicone samples exposed under ambient air environment coupled with measurements of collected volatile condensable material (CVCM) and total mass loss (TML) per the standard conditions in ASTM E 595. The data will show an insignificant effect on the CVCMs and TMLs after exposure to various dosages of gamma radiation. This data may favorably impact new applications for these silicone materials for use as an improved sealant for space solar cell systems, space structures, satellite systems and aerospace systems.

Thermal Model Development for an X-Ray Mirror Assembly

NASA Technical Reports Server (NTRS)

Bonafede, Joseph A.

2015-01-01

Space-based x-ray optics require stringent thermal environmental control to achieve the desired image quality. Future x-ray telescopes will employ hundreds of nearly cylindrical, thin mirror shells to maximize effective area, with each shell built from small azimuthal segment pairs for manufacturability. Thermal issues with these thin optics are inevitable because the mirrors must have a near unobstructed view of space while maintaining near uniform 20 C temperature to avoid thermal deformations. NASA Goddard has been investigating the thermal characteristics of a future x-ray telescope with an image requirement of 5 arc-seconds and only 1 arc-second focusing error allocated for thermal distortion. The telescope employs 135 effective mirror shells formed from 7320 individual mirror segments mounted in three rings of 18, 30, and 36 modules each. Thermal requirements demand a complex thermal control system and detailed thermal modeling to verify performance. This presentation introduces innovative modeling efforts used for the conceptual design of the mirror assembly and presents results demonstrating potential feasibility of the thermal requirements.

Detecting Chemical Weapons: Threats, Requirements, Solutions, and Future Challenges

NASA Astrophysics Data System (ADS)

Boso, Brian

2011-03-01

Although chemicals have been reportedly used as weapons for thousands of years, it was not until 1915 at Ypres, France that an industrial chemical, chlorine, was used in World War I as an offensive weapon in significant quantity, causing mass casualties. From that point until today the development, detection, production and protection from chemical weapons has be an organized endeavor of many of the world's armed forces and in more recent times, non-governmental terrorist organizations. The number of Chemical Warfare Agents (CWAs) has steadily increased as research into more toxic substances continued for most of the 20 th century. Today there are over 70 substances including harassing agents like tear gas, incapacitating agents, and lethal agents like blister, blood, chocking, and nerve agents. The requirements for detecting chemical weapons vary depending on the context in which they are encountered and the concept of operation of the organization deploying the detection equipment. The US DoD, for example, has as a requirement, that US forces be able to continue their mission, even in the event of a chemical attack. This places stringent requirements on detection equipment. It must be lightweight (<2 lbs), detect a large array of chemical warfare agents and toxic industrial chemicals, detect and warn at concentration levels and time duration to prevent acute health effects, meet military ruggedness specifications and work over a wide range of temperature and humidity, and have a very high probability of detection with a similarly low probability of false positives. The current technology of choice to meet these stringent requirements is Ion Mobility Spectrometry. Many technologies are capable of detecting chemicals at the trace levels required and have been extensively developed for this application, including, but not limited to: mass spectroscopy, IR spectroscopy, RAMAN spectroscopy, MEMs micro-cantilever sensors, surface acoustic wave sensors, differential mobility spectrometry, and amplifying fluorescence polymers. In the future the requirements for detection equipment will continue to become even more stringent. The continuing increase in the sheer number of threats that will need to be detected, the development of binary agents requiring that even the precursor chemicals be detected, the development of new types of agents unlike any of the current chemistries, and the expansion of the list of toxic industrial chemical will require new techniques with higher specificity and more sensitivity.

Wire-Arc-Sprayed Aluminum Protects Steel Against Corrosion

NASA Technical Reports Server (NTRS)

Zimmerman, Frank R.; Poorman, Richard; Sanders, Heather L.; Mckechnie, Timothy N.; Bonds, James W., Jr.; Daniel, Ronald L., Jr.

1995-01-01

Aluminum coatings wire-arc sprayed onto steel substrates found effective in protecting substrates against corrosion. Coatings also satisfy stringent requirements for adhesion and flexibility, both at room temperature and at temperatures as low as liquid hydrogen. Developed as alternatives to corrosion-inhibiting primers and paints required by law to be phased out because they contain and emit such toxic substances as chromium and volatile organic compounds.

Ultrasound Picture Archiving And Communication Systems

NASA Astrophysics Data System (ADS)

Koestner, Ken; Hottinger, C. F.

1982-01-01

The ideal ultrasonic image communication and storage system must be flexible in order to optimize speed and minimize storage requirements. Various ultrasonic imaging modalities are quite different in data volume and speed requirements. Static imaging, for example B-Scanning, involves acquisition of a large amount of data that is averaged or accumulated in a desired manner. The image is then frozen in image memory before transfer and storage. Images are commonly a 512 x 512 point array, each point 6 bits deep. Transfer of such an image over a serial line at 9600 baud would require about three minutes. Faster transfer times are possible; for example, we have developed a parallel image transfer system using direct memory access (DMA) that reduces the time to 16 seconds. Data in this format requires 256K bytes for storage. Data compression can be utilized to reduce these requirements. Real-time imaging has much more stringent requirements for speed and storage. The amount of actual data per frame in real-time imaging is reduced due to physical limitations on ultrasound. For example, 100 scan lines (480 points long, 6 bits deep) can be acquired during a frame at a 30 per second rate. In order to transmit and save this data at a real-time rate requires a transfer rate of 8.6 Megabaud. A real-time archiving system would be complicated by the necessity of specialized hardware to interpolate between scan lines and perform desirable greyscale manipulation on recall. Image archiving for cardiology and radiology would require data transfer at this high rate to preserve temporal (cardiology) and spatial (radiology) information.

Whole-Genome Microarray and Gene Deletion Studies Reveal Regulation of the Polyhydroxyalkanoate Production Cycle by the Stringent Response in Ralstonia eutropha H16

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

Brigham, CJ; Speth, DR; Rha, C

Poly(3-hydroxybutyrate) (PHB) production and mobilization in Ralstonia eutropha are well studied, but in only a few instances has PHB production been explored in relation to other cellular processes. We examined the global gene expression of wild-type R. eutropha throughout the PHB cycle: growth on fructose, PHB production using fructose following ammonium depletion, and PHB utilization in the absence of exogenous carbon after ammonium was resupplied. Our results confirm or lend support to previously reported results regarding the expression of PHB-related genes and enzymes. Additionally, genes for many different cellular processes, such as DNA replication, cell division, and translation, are selectivelymore » repressed during PHB production. In contrast, the expression levels of genes under the control of the alternative sigma factor sigma(54) increase sharply during PHB production and are repressed again during PHB utilization. Global gene regulation during PHB production is strongly reminiscent of the gene expression pattern observed during the stringent response in other species. Furthermore, a ppGpp synthase deletion mutant did not show an accumulation of PHB, and the chemical induction of the stringent response with DL-norvaline caused an increased accumulation of PHB in the presence of ammonium. These results indicate that the stringent response is required for PHB accumulation in R. eutropha, helping to elucidate a thus-far-unknown physiological basis for this process.« less

Modernizing the automatic temperature-regulating systems for electric resistor furnaces

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

Anchevskii, I.V.; Afanasiadi, N.G.; Demin, V.P.

An analysis of the technical level of heat-treating equipment at the sector's plants showed that automation was either insufficient or completely lacking. Modern heat-treating technology makes stringent demands on heat-treating equipment, including electric resistor furnaces. Therefore, it became necessary to modernize these furnaces and equip them with modern automatic temperature control systems (ATCSs). This is most urgent for furnaces which handle nuclear-power-station parts, which must not only be held at a certain temperature for a definite time, but which also require a complex process with established heating rates in each time period. The heat-treatment data are recorded in the part'smore » passport certificate, and the temperatures of both the heatingzone atmosphere and the heat-treated part are monitored.« less

Mission building blocks for outer solar system exploration.

NASA Technical Reports Server (NTRS)

Herman, D.; Tarver, P.; Moore, J.

1973-01-01

Description of the technological building blocks required for exploring the outer planets with maximum scientific yields under stringent resource constraints. Two generic spacecraft types are considered: the Mariner and the Pioneer. Following a discussion of the outer planet mission constraints, the evolutionary development of spacecraft, probes, and propulsion building blocks is presented. Then, program genealogies are shown for Pioneer and Mariner missions and advanced propulsion systems to illustrate the soundness of a program based on spacecraft modification rather than on the development of new spacecraft for each mission. It is argued that, for minimum costs, technological advancement should occur in an evolutionary manner from mission to mission. While this strategy is likely to result in compromises on specific missions, the realization of the overall objectives calls for an advance commitment to the entire mission series.

High-port low-latency optical switch architecture with optical feed-forward buffering for 256-node disaggregated data centers.

PubMed

Terzenidis, Nikos; Moralis-Pegios, Miltiadis; Mourgias-Alexandris, George; Vyrsokinos, Konstantinos; Pleros, Nikos

2018-04-02

Departing from traditional server-centric data center architectures towards disaggregated systems that can offer increased resource utilization at reduced cost and energy envelopes, the use of high-port switching with highly stringent latency and bandwidth requirements becomes a necessity. We present an optical switch architecture exploiting a hybrid broadcast-and-select/wavelength routing scheme with small-scale optical feedforward buffering. The architecture is experimentally demonstrated at 10Gb/s, reporting error-free performance with a power penalty of <2.5dB. Moreover, network simulations for a 256-node system, revealed low-latency values of only 605nsec, at throughput values reaching 80% when employing 2-packet-size optical buffers, while multi-rack network performance was also investigated.

Seismic isolation of Advanced LIGO: Review of strategy, instrumentation and performance

NASA Astrophysics Data System (ADS)

Matichard, F.; Lantz, B.; Mittleman, R.; Mason, K.; Kissel, J.; Abbott, B.; Biscans, S.; McIver, J.; Abbott, R.; Abbott, S.; Allwine, E.; Barnum, S.; Birch, J.; Celerier, C.; Clark, D.; Coyne, D.; DeBra, D.; DeRosa, R.; Evans, M.; Foley, S.; Fritschel, P.; Giaime, J. A.; Gray, C.; Grabeel, G.; Hanson, J.; Hardham, C.; Hillard, M.; Hua, W.; Kucharczyk, C.; Landry, M.; Le Roux, A.; Lhuillier, V.; Macleod, D.; Macinnis, M.; Mitchell, R.; O'Reilly, B.; Ottaway, D.; Paris, H.; Pele, A.; Puma, M.; Radkins, H.; Ramet, C.; Robinson, M.; Ruet, L.; Sarin, P.; Shoemaker, D.; Stein, A.; Thomas, J.; Vargas, M.; Venkateswara, K.; Warner, J.; Wen, S.

2015-09-01

The new generation of gravitational waves detectors require unprecedented levels of isolation from seismic noise. This article reviews the seismic isolation strategy and instrumentation developed for the Advanced LIGO observatories. It summarizes over a decade of research on active inertial isolation and shows the performance recently achieved at the Advanced LIGO observatories. The paper emphasizes the scientific and technical challenges of this endeavor and how they have been addressed. An overview of the isolation strategy is given. It combines multiple layers of passive and active inertial isolation to provide suitable rejection of seismic noise at all frequencies. A detailed presentation of the three active platforms that have been developed is given. They are the hydraulic pre-isolator, the single-stage internal isolator and the two-stage internal isolator. The architecture, instrumentation, control scheme and isolation results are presented for each of the three systems. Results show that the seismic isolation sub-system meets Advanced LIGO’s stringent requirements and robustly supports the operation of the two detectors.

KSC Center Director Bridges accepts an ISO 9001 certificate from DNV

NASA Technical Reports Server (NTRS)

1998-01-01

Center Director Roy Bridges displays the ISO 9001 certificate he was awarded by Det Norske Veritas (DNV), Inc., an international ISO certification organization, at a ceremony at KSC. Dalton Lyon of DNV made the presentation, which included a 2000th ISO Certificate Plaque. ISO 9001 comprises the most detailed, comprehensive set of standard requirements for quality programs established by the International Standards Organization. The presentation followed a successful independent audit by DNV of the KSC Management System in May of this year. The third-party auditors examined about 20 elements of KSC's system, including management responsibility, design control, documentation, test and inspection, and corrective action procedures. DNV found that KSC met or exceeded the stringent quality standards in all areas. KSC will use this certification as a tool to improve an already world-class team. All NASA centers are required by NASA Administrator Daniel S. Goldin to be ISO 9001 registered by September 1999. NASA is the first federal agency to seek the quality certification.

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

Cushman, Jeremy S.; Dally, Adam; Davis, Christopher J.

The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale cryogenic experiment designed to search for neutrinoless double-beta decay of 130Te and other rare events. The CUORE detector consists of 988 TeO 2 bolometers operated underground at 10 mK in a dilution refrigerator at the Laboratori Nazionali del Gran Sasso. Candidate events are identified through a precise measurement of their energy. The absolute energy response of the detectors is established by the regular calibration of each individual bolometer using gamma sources. The close-packed configuration of the CUORE bolometer array combined with the extensive shielding surrounding the detectors requires themore » placement of calibration sources within the array itself. The CUORE Detector Calibration System is designed to insert radioactive sources into and remove them from the cryostat while respecting the stringent heat load, radiopurity, and operational requirements of the experiment. In conclusion, this paper describes the design, commissioning, and performance of this novel source calibration deployment system for ultra-low-temperature environments.« less

KSC-98pc907

NASA Image and Video Library

1998-08-11

Center Director Roy Bridges displays the ISO 9001 certificate he was awarded by Det Norske Veritas (DNV), Inc., an international ISO certification organization, at a ceremony at KSC. Dalton Lyon of DNV made the presentation, which included a 2000th ISO Certificate Plaque. ISO 9001 comprises the most detailed, comprehensive set of standard requirements for quality programs established by the International Standards Organization. The presentation followed a successful independent audit by DNV of the KSC Management System in May of this year. The third-party auditors examined about 20 elements of KSC's system, including management responsibility, design control, documentation, test and inspection, and corrective action procedures. DNV found that KSC met or exceeded the stringent quality standards in all areas. KSC will use this certification as a tool to improve an already world-class team. All NASA centers are required by NASA Administrator Daniel S. Goldin to be ISO 9001 registered by September 1999. NASA is the first federal agency to seek the quality certification

KSC-98pc908

NASA Image and Video Library

1998-08-11

Center Director Roy Bridges (right) displays the 2000th ISO Certificate Plaque he was given by Dalton Lyon (left) of Det Norske Veritas (DNV), Inc., an international ISO certification organization, at a ceremony at KSC. The plaque is a representation of the ISO 9001 certification awarded to KSC by DNV. ISO 9001 comprises the most detailed, comprehensive set of standard requirements for quality programs established by the International Standards Organization. The presentation followed a successful independent audit by DNV of the KSC Management System in May of this year. The third-party auditors examined about 20 elements of KSC's system, including management responsibility, design control, documentation, test and inspection, and corrective action procedures. DNV found that KSC met or exceeded the stringent quality standards in all areas. KSC will use this certification as a tool to improve an already worldclass team. All NASA centers are required by NASA Administrator Daniel S. Goldin to be ISO 9001 registered by September 1999. NASA is the first federal agency to seek the quality certification

Regional ITS architecture guidance : developing, using, and maintaining an ITS architecture for your region

DOT National Transportation Integrated Search

1998-08-01

The purpose of this TechBrief is to discuss one of the Long Term Pavement Performance (LTPP) program's stringent data requirements - site-specific measurements for estimating pavement loadings - and to illustrate the effects of traffic loading data e...

EFFECTS OF CHANGING DISINFECTANTS ON LEAD AND COPPER RELEASE– A REVIEW

EPA Science Inventory

More utilities are using chloramines in place of free chlorine for greater residual stability and better compliance with both the Total Coliform Rule (TCR) and more stringent requirements of the Disinfectants/Disinfection By-Products Rule (D/DBPR). However, new information about ...

20 CFR 658.701 - Statements of policy.

Code of Federal Regulations, 2010 CFR

2010-04-01

... ensure that State agencies comply with all requirements established by JS regulations. (b) It is the... continual violations of JS regulations if less stringent remedial actions taken in accordance with this... alleged violations by State agencies of the JS regulations received from any person or organization. ...

Avoiding Title V permitting pitfalls

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

Laswell, D.L.

1993-04-01

Title V of the 1990 Clean Air Act Amendments requires states to implement new air operating permit programs. States have a great deal of flexibility in developing their permit programs. Industry should work now to ensure that state programs contain the favorable aspects of the federal regulations and do not contain more stringent requirements that are not required under the Clean Air Act. This article outlines areas of the permit program that have the potential to handicap industry`s ability to expand.

Hubble Space Telescope servicing mission scientific instrument protective enclosure design requirements and contamination controls

NASA Technical Reports Server (NTRS)

Hansen, Patricia A.; Hughes, David W.; Hedgeland, Randy J.; Chivatero, Craig J.; Studer, Robert J.; Kostos, Peter J.

1994-01-01

The Scientific Instrument Protective Enclosures were designed for the Hubble Space Telescope Servicing Missions to provide a beginning environment to a Scientific Instrument during ground and on orbit activities. The Scientific Instruments required very stringent surface cleanliness and molecular outgassing levels to maintain ultraviolet performance. Data from the First Servicing Mission verified that both the Scientific Instruments and Scientific Instrument Protective Enclosures met surface cleanliness level requirements during ground and on-orbit activities.

The Orbital Design of Alpha Centauri Exoplanet Satellite (ACESat)

NASA Technical Reports Server (NTRS)

Weston, Sasha; Belikov, Rus; Bendek, Eduardo

2015-01-01

Exoplanet candidates discovered by Kepler are too distant for biomarkers to be detected with foreseeable technology. Alpha Centauri has high separation from other stars and is of close proximity to Earth, which makes the binary star system 'low hanging fruit' for scientists. Alpha Centauri Exoplanet Satellite (ACESat) is a mission proposed to Small Explorer Program (SMEX) that will use a coronagraph to search for an orbiting planet around one of the stars of Alpha Centauri. The trajectory design for this mission is presented here where three different trajectories are considered: Low Earth Orbit (LEO), Geosynchronous Orbit (GEO) and a Heliocentric Orbit. Uninterrupted stare time to Alpha Centauri is desirable for meeting science requirements, or an orbit that provides 90% stare time to the science target. The instrument thermal stability also has stringent requirements for proper function, influencing trajectory design.

Auralization Architectures for NASA?s Next Generation Aircraft Noise Prediction Program

NASA Technical Reports Server (NTRS)

Rizzi, Stephen A.; Lopes, Leonard V.; Burley, Casey L.; Aumann, Aric R.

2013-01-01

Aircraft community noise is a significant concern due to continued growth in air traffic, increasingly stringent environmental goals, and operational limitations imposed by airport authorities. The assessment of human response to noise from future aircraft can only be afforded through laboratory testing using simulated flyover noise. Recent work by the authors demonstrated the ability to auralize predicted flyover noise for a state-of-the-art reference aircraft and a future hybrid wing body aircraft concept. This auralization used source noise predictions from NASA's Aircraft NOise Prediction Program (ANOPP) as input. The results from this process demonstrated that auralization based upon system noise predictions is consistent with, and complementary to, system noise predictions alone. To further develop and validate the auralization process, improvements to the interfaces between the synthesis capability and the system noise tools are required. This paper describes the key elements required for accurate noise synthesis and introduces auralization architectures for use with the next-generation ANOPP (ANOPP2). The architectures are built around a new auralization library and its associated Application Programming Interface (API) that utilize ANOPP2 APIs to access data required for auralization. The architectures are designed to make the process of auralizing flyover noise a common element of system noise prediction.

Revitalizing the Space Shuttle's Thermal Protection System with Reverse Engineering and 3D Vision Technology

NASA Technical Reports Server (NTRS)

Wilson, Brad; Galatzer, Yishai

2008-01-01

The Space Shuttle is protected by a Thermal Protection System (TPS) made of tens of thousands of individually shaped heat protection tile. With every flight, tiles are damaged on take-off and return to earth. After each mission, the heat tiles must be fixed or replaced depending on the level of damage. As part of the return to flight mission, the TPS requirements are more stringent, leading to a significant increase in heat tile replacements. The replacement operation requires scanning tile cavities, and in some cases the actual tiles. The 3D scan data is used to reverse engineer each tile into a precise CAD model, which in turn, is exported to a CAM system for the manufacture of the heat protection tile. Scanning is performed while other activities are going on in the shuttle processing facility. Many technicians work simultaneously on the space shuttle structure, which results in structural movements and vibrations. This paper will cover a portable, ultra-fast data acquisition approach used to scan surfaces in this unstable environment.

Space shuttle orbiter auxiliary power unit development challenges

NASA Technical Reports Server (NTRS)

Lance, R.; Weary, D.

1985-01-01

When the flying spacecraft was approved for development, a power unit for the hydraulic system had to be developed. Unlike other systems on the orbiter, there was no precedent in earlier spacecraft for a hydraulic system nor for the power unit to drive the hydraulic pumps. The only prototypes available were airplane auxiliary power units (APU), which were not required to operate in the severe environments of a spacecraft nor to have the longevity of an orbiter hydraulic power unit. The challenge was to build a hydraulic power unit which could operate in 0g or 3g, in a vacuum or at sea level pressure, and at -65 F or 225 F, which would be capable of restarting while hot, and which would be capable of sustaining the hydraulic loads for the life of the orbiter. The basic approach to providing hydraulic power for the orbiter was to use a small, high speed, monopropellant fueled turbine power unit to drive a conventional aircraft type hydraulic pump. The stringent requirements imposed on the orbiter APU quickly made this machine different from existing aircraft APUs.

Robust Multilayer Insulation for Cryogenic Systems

NASA Technical Reports Server (NTRS)

Fesmire, J. E.; Scholtens, B. F.; Augustynowicz, S. D.

2007-01-01

New requirements for thermal insulation include robust Multilayer insulation (MU) systems that work for a range of environments from high vacuum to no vacuum. Improved MLI systems must be simple to install and maintain while meeting the life-cycle cost and thermal performance objectives. Performance of actual MLI systems has been previously shown to be much worse than ideal MLI. Spacecraft that must contain cryogens for both lunar service (high vacuum) and ground launch operations (no vacuum) are planned. Future cryogenic spacecraft for the soft vacuum environment of Mars are also envisioned. Industry products using robust MLI can benefit from improved cost-efficiency and system safety. Novel materials have been developed to operate as excellent thermal insulators at vacuum levels that are much less stringent than the absolute high vacuum requirement of current MLI systems. One such robust system, Layered Composite Insulation (LCI), has been developed by the Cryogenics Test Laboratory at NASA Kennedy Space Center. The experimental testing and development of LCI is the focus of this paper. LCI thermal performance under cryogenic conditions is shown to be six times better than MLI at soft vacuum and similar to MLI at high vacuum. The experimental apparent thermal conductivity (k-value) and heat flux data for LCI systems are compared with other MLI systems.

Engineering Design of ITER Prototype Fast Plant System Controller

NASA Astrophysics Data System (ADS)

Goncalves, B.; Sousa, J.; Carvalho, B.; Rodrigues, A. P.; Correia, M.; Batista, A.; Vega, J.; Ruiz, M.; Lopez, J. M.; Rojo, R. Castro; Wallander, A.; Utzel, N.; Neto, A.; Alves, D.; Valcarcel, D.

2011-08-01

The ITER control, data access and communication (CODAC) design team identified the need for two types of plant systems. A slow control plant system is based on industrial automation technology with maximum sampling rates below 100 Hz, and a fast control plant system is based on embedded technology with higher sampling rates and more stringent real-time requirements than that required for slow controllers. The latter is applicable to diagnostics and plant systems in closed-control loops whose cycle times are below 1 ms. Fast controllers will be dedicated industrial controllers with the ability to supervise other fast and/or slow controllers, interface to actuators and sensors and, if necessary, high performance networks. Two prototypes of a fast plant system controller specialized for data acquisition and constrained by ITER technological choices are being built using two different form factors. This prototyping activity contributes to the Plant Control Design Handbook effort of standardization, specifically regarding fast controller characteristics. Envisaging a general purpose fast controller design, diagnostic use cases with specific requirements were analyzed and will be presented along with the interface with CODAC and sensors. The requirements and constraints that real-time plasma control imposes on the design were also taken into consideration. Functional specifications and technology neutral architecture, together with its implications on the engineering design, were considered. The detailed engineering design compliant with ITER standards was performed and will be discussed in detail. Emphasis will be given to the integration of the controller in the standard CODAC environment. Requirements for the EPICS IOC providing the interface to the outside world, the prototype decisions on form factor, real-time operating system, and high-performance networks will also be discussed, as well as the requirements for data streaming to CODAC for visualization and archiving.

78 FR 20912 - Clean Water Act: Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-08

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9798-8] Clean Water Act: Availability of List Decisions.... SUMMARY: The Clean Water Act requires that States periodically submit, and EPA approve or disapprove... are not stringent enough to attain or maintain State water quality standards and for which total...

43 CFR 420.12 - Requirements-operators.

Code of Federal Regulations, 2012 CFR

2012-10-01

... THE INTERIOR OFF-ROAD VEHICLE USE Operating Criteria § 420.12 Requirements—operators. (a) In addition... off-road vehicles; if State laws are lacking or less stringent than the regulations established in... operator of an off-road vehicle operated on Reclamation lands shall possess a valid motor vehicle operator...

43 CFR 420.12 - Requirements-operators.

Code of Federal Regulations, 2013 CFR

2013-10-01

... THE INTERIOR OFF-ROAD VEHICLE USE Operating Criteria § 420.12 Requirements—operators. (a) In addition... off-road vehicles; if State laws are lacking or less stringent than the regulations established in... operator of an off-road vehicle operated on Reclamation lands shall possess a valid motor vehicle operator...

43 CFR 420.12 - Requirements-operators.

Code of Federal Regulations, 2014 CFR

2014-10-01

... THE INTERIOR OFF-ROAD VEHICLE USE Operating Criteria § 420.12 Requirements—operators. (a) In addition... off-road vehicles; if State laws are lacking or less stringent than the regulations established in... operator of an off-road vehicle operated on Reclamation lands shall possess a valid motor vehicle operator...

The Dangers of Aestheticism in Schooling.

ERIC Educational Resources Information Center

Meager, Ruby

1981-01-01

Prompted by Immanuel Kant's analysis of the nature and operations of the imagination in his "Critique of the Aesthetical Judgment," this article points out the danger of encouraging imagination-borne aesthetical judgments and explanatory hypotheses. Concludes that understanding requires submission to more stringent standards of objectivity and to…

An Introduction to Modern Missing Data Analyses

ERIC Educational Resources Information Center

Baraldi, Amanda N.; Enders, Craig K.

2010-01-01

A great deal of recent methodological research has focused on two modern missing data analysis methods: maximum likelihood and multiple imputation. These approaches are advantageous to traditional techniques (e.g. deletion and mean imputation techniques) because they require less stringent assumptions and mitigate the pitfalls of traditional…

40 CFR 256.21 - Requirements for State regulatory powers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... WASTES GUIDELINES FOR DEVELOPMENT AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Solid Waste... be adequate to enforce solid waste disposal standards which are equivalent to or more stringent than the criteria for classification of solid waste disposal facilities (40 CFR part 257). Such authority...

40 CFR 256.21 - Requirements for State regulatory powers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... WASTES GUIDELINES FOR DEVELOPMENT AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Solid Waste... be adequate to enforce solid waste disposal standards which are equivalent to or more stringent than the criteria for classification of solid waste disposal facilities (40 CFR part 257). Such authority...

43 CFR 420.12 - Requirements-operators.

Code of Federal Regulations, 2010 CFR

2010-10-01

... snowmobiles, trail bikes, and any other off road vehicle the operator shall wear safety equipment, generally... THE INTERIOR OFF-ROAD VEHICLE USE Operating Criteria § 420.12 Requirements—operators. (a) In addition... off-road vehicles; if State laws are lacking or less stringent than the regulations established in...

43 CFR 420.12 - Requirements-operators.

Code of Federal Regulations, 2011 CFR

2011-10-01

... snowmobiles, trail bikes, and any other off road vehicle the operator shall wear safety equipment, generally... THE INTERIOR OFF-ROAD VEHICLE USE Operating Criteria § 420.12 Requirements—operators. (a) In addition... off-road vehicles; if State laws are lacking or less stringent than the regulations established in...

Using Common Planning Time to Foster Professional Learning

ERIC Educational Resources Information Center

Dever, Robin; Lash, Martha J.

2013-01-01

Increased emphasis on meeting state standards, more stringent requirements for designation as highly qualified, and intensified accountability for student performance have foisted new expectations upon teachers and stimulated changes in professional development models in which the greater urgency is clearly to attend to the teacher's role as…

Field dodder (Cuscuta campestris) control with flumioxazin

USDA-ARS?s Scientific Manuscript database

Field dodder is an important weed in alfalfa grown for seed production, requiring stringent control to keep the alfalfa seed free of dodder seed contamination. Pendimethalin has been the primary tool used to control dodder in alfalfa seed production for over 25 years. Flumioxazin was recently regis...

Public Water System Supervision Program Revision for the State of Nevada

EPA Pesticide Factsheets

Nevada revised its approved Public Water System Supervision Program under the federal Safe Drinking Water Act. EPA has determined that these revisions by the State of Nevada are no less stringent than the corresponding Federal regulations.

Stringency and relaxation among the halobacteria.

PubMed Central

Cimmino, C; Scoarughi, G L; Donini, P

1993-01-01

Accumulation of stable RNA and production of guanosine polyphosphates (ppGpp and pppGpp) were studied during amino acid starvation in four species of halobacteria. In two of the four species, stable RNA was under stringent control, whereas one of the remaining two species was relaxed and the other gave an intermediate phenotype. The stringent reaction was reversed by anisomycin, an effect analogous to the chloroamphenicol-induced reversal of stringency in the eubacteria. During the stringent response, neither ppGpp nor pppGpp accumulation took place during starvation. In both growing and starved cells a very low basal level of the two polyphosphates appeared to be present. In the stringent species the intracellular concentration of GTP did not diminish but actually increased during the course of the stringent response. These data demonstrate that (i) wild-type halobacteria can have either the stringent or the relaxed phenotype (all wild-type eubacteria tested have been shown to be stringent); (ii) stringency in the halobacteria is dependent on the deaminoacylation of tRNA, as in the eubacteria; and (iii) in the halobacteria, ppGpp is not an effector of stringent control over stable-RNA synthesis. Images PMID:7691798

Radiation-hardened microwave communications system

NASA Astrophysics Data System (ADS)

Smith, S. F.; Bible, D. W.; Crutcher, R. I.; Hannah, J. H.; Moore, J. A.; Nowlin, C. H.; Vandermolen, R. I.; Chagnot, D.; Leroy, A.

1993-03-01

To develop a wireless communication system to meet the stringent requirements for a nuclear hot cell and similar environments, including control of advanced servomanipulators, a microwave signal transmission system development program was established to produce a demonstration prototype for the Consolidated Fuel Reprocessing Program at Oak Ridge National Laboratory (ORNL). Proof-of-principle tests in a partially metal lined enclosure at ORNL successfully demonstrated the feasibility of directed microwave signal transmission techniques for remote systems applications. The potential for much more severe radio-frequency (RF) multipath propagation conditions in fully metal lined cells led to a programmatic decision to conduct additional testing in more typical hot-cell environments at other sites. Again, the test results were excellent. Based on the designs of the earlier systems, an advanced microwave signal transmission system configuration was subsequently developed that, in highly reflective environments, will support both high-performance video channels and high baud-rate digital data links at total gamma dose tolerance levels exceeding 10(exp 7) rads and at elevated ambient temperatures.

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

NONE

Toshiba Display Services, a television picture-tube manufacturer in Horseheads, NY, recently was able to meet stringent state regulations to reduce emissions from two of its film applications lines by installing a regenerative catalytic oxidation system. Toshiba officials initially evaluated several technologies to control volatile organic compounds. After deciding that oxidation was the best technology for its facility, the company invited a number of suppliers to submit proposals. Because all of the oxidation technologies considered by Toshiba had the capability to achieve the destruction and removal efficiency requirement, the company combined the second and third decision elements and conducted an in-depthmore » comparison of the initial capital and ongoing operating costs for each proposal. Officials narrowed the field to two systems--the lowest-cost regenerative thermal oxidation system on the market and a regenerative catalytic oxidation system. The company selected St. Louis, Mo.-based Monsanto Enviro-Chem Systems Inc., to install its DynaCycle{reg_sign} regenerative catalytic oxidation system, marking the first Dyna-Cycle installation in a US television picture-tube facility.« less

Assessment of Logistics Effectiveness for Expeditionary Units

DTIC Science & Technology

2017-12-01

navigating the bureaucracy when spending government money requires the ESU teams to be savvy supply experts. Figure 8. EOD Force Laydown. Source...main uses is to help free a trapped diver from any number of hazards. The MK-16 equipment must withstand these conditions and not puncture...of the valves being shipped to the units as repair parts. The pieces require an oxygen- free environment for testing, along with other stringent

Contamination monitoring approaches for EUV space optics

NASA Technical Reports Server (NTRS)

Ray, David C.; Malina, Roger F.; Welsh, Barry J.; Battel, Steven J.

1989-01-01

Data from contaminant-induced UV optics degradation studies and particulate models are used here to develop end-of-service-life instrument contamination requirements which are very stringent but achievable. The budget is divided into allocations for each phase of hardware processing. Optical and nonoptical hardware are monitored for particulate and molecular contamination during initial cleaning and baking, assembly, test, and calibration phases. The measured contamination levels are compared to the requirements developed for each phase to provide confidence that the required end-of-life levels will be met.

Applications and challenges of multivalent recombinant vaccines

PubMed Central

Naim, Hussein Y.

2013-01-01

The exceptional discoveries of antigen/gene delivery systems have allowed the development of novel prophylactic and therapeutic vaccine candidates. The vaccine candidates employ various antigen-delivery systems, particularly recombinant viral vectors. Recombinant viral vectors are experimental vaccines similar to DNA vaccines, but they use attenuated viruses or bacterium as a carrier “vector” to introduce microbial DNA to cells of the body. They closely mimic a natural infection and therefore can efficiently stimulate the immune system. Although such recombinant vectors may face extensive preclinical testing and will possibly have to meet stringent regulatory requirements, some of these vectors (e.g. measles virus vectors) may benefit from the profound industrial and clinical experience of the parent vaccine. Most notably, novel vaccines based on live attenuated viruses combine the induction of broad, strong and persistent immune responses with acceptable safety profiles. We assess certain technologies in light of their use against human immunodeficiency virus (HIV). PMID:23249651

Engineering of the LISA Pathfinder mission—making the experiment a practical reality

NASA Astrophysics Data System (ADS)

Warren, Carl; Dunbar, Neil; Backler, Mike

2009-05-01

LISA Pathfinder represents a unique challenge in the development of scientific spacecraft—not only is the LISA Test Package (LTP) payload a complex integrated development, placing stringent requirements on its developers and the spacecraft, but the payload also acts as the core sensor and actuator for the spacecraft, making the tasks of control design, software development and system verification unusually difficult. The micro-propulsion system which provides the remaining actuation also presents substantial development and verification challenges. As the mission approaches the system critical design review, flight hardware is completing verification and the process of verification using software and hardware simulators and test benches is underway. Preparation for operations has started, but critical milestones for LTP and field effect electric propulsion (FEEP) lie ahead. This paper summarizes the status of the present development and outlines the key challenges that must be overcome on the way to launch.

Integration of power over fiber on RoF systems in different scenarios

NASA Astrophysics Data System (ADS)

Vázquez, C.; Montero, D. S.; Pinzón, P. J.; López-Cardona, J. D.; Contreras, P.; Tapetado, A.

2017-01-01

Future high capacity of the 5th Generation radio environment will boost transport networks to be adapted. The high bandwidth, together with stringent delay and jitter requirements, make dedicated optical connectivity a preferred solution for fronthaul. Those Radio Access Networks apart from higher capacity and lower latency should have higher energy efficiency. In order to cover this aspect, power over fiber has been pointed out as a key technology for that purpose having in mind that control plane will be centralized on future Cloud RAN and that sometimes Remote Radio Heads should be deployed in places lacking external power supply in order to fulfill the desired coverage. In this paper, different scenarios on potential demanding environments of power over fiber on Radio over Fiber systems such as automotive, in-house and remote mobile fronthaul will be discussed. Some tests on power over fiber systems based on different optical fibers are provided.

HETDEX tracker control system design and implementation

NASA Astrophysics Data System (ADS)

Beno, Joseph H.; Hayes, Richard; Leck, Ron; Penney, Charles; Soukup, Ian

2012-09-01

To enable the Hobby-Eberly Telescope Dark Energy Experiment, The University of Texas at Austin Center for Electromechanics and McDonald Observatory developed a precision tracker and control system - an 18,000 kg robot to position a 3,100 kg payload within 10 microns of a desired dynamic track. Performance requirements to meet science needs and safety requirements that emerged from detailed Failure Modes and Effects Analysis resulted in a system of 13 precision controlled actuators and 100 additional analog and digital devices (primarily sensors and safety limit switches). Due to this complexity, demanding accuracy requirements, and stringent safety requirements, two independent control systems were developed. First, a versatile and easily configurable centralized control system that links with modeling and simulation tools during the hardware and software design process was deemed essential for normal operation including motion control. A second, parallel, control system, the Hardware Fault Controller (HFC) provides independent monitoring and fault control through a dedicated microcontroller to force a safe, controlled shutdown of the entire system in the event a fault is detected. Motion controls were developed in a Matlab-Simulink simulation environment, and coupled with dSPACE controller hardware. The dSPACE real-time operating system collects sensor information; motor commands are transmitted over a PROFIBUS network to servo amplifiers and drive motor status is received over the same network. To interface the dSPACE controller directly to absolute Heidenhain sensors with EnDat 2.2 protocol, a custom communication board was developed. This paper covers details of operational control software, the HFC, algorithms, tuning, debugging, testing, and lessons learned.

Thermal Design to Meet Stringent Temperature Gradient/Stability Requirements of SWIFT BAT Detectors

NASA Technical Reports Server (NTRS)

Choi, Michael K.

2000-01-01

The Burst Alert Telescope (BAT) is an instrument on the National Aeronautics and Space Administration (NASA) SWIFT spacecraft. It is designed to detect gamma ray burst over a broad region of the sky and quickly align the telescopes on the spacecraft to the gamma ray source. The thermal requirements for the BAT detector arrays are very stringent. The maximum allowable temperature gradient of the 256 cadmium zinc telluride (CZT) detectors is PC. Also, the maximum allowable rate of temperature change of the ASICs of the 256 Detector Modules (DMs) is PC on any time scale. The total power dissipation of the DMs and Block Command & Data Handling (BCDH) is 180 W. This paper presents a thermal design that uses constant conductance heat pipes (CCHPs) to minimize the temperature gradient of the DMs, and loop heat pipes (LHPs) to transport the waste heat to the radiator. The LHPs vary the effective thermal conductance from the DMs to the radiator to minimize heater power to meet the heater power budget, and to improve the temperature stability. The DMs are cold biased, and active heater control is used to meet the temperature gradient and stability requirements.

Violation of continuous-variable Einstein-Podolsky-Rosen steering with discrete measurements.

PubMed

Schneeloch, James; Dixon, P Ben; Howland, Gregory A; Broadbent, Curtis J; Howell, John C

2013-03-29

In this Letter, we derive an entropic Einstein-Podolsky-Rosen (EPR) steering inequality for continuous-variable systems using only experimentally measured discrete probability distributions and details of the measurement apparatus. We use this inequality to witness EPR steering between the positions and momenta of photon pairs generated in spontaneous parametric down-conversion. We examine the asymmetry between parties in this inequality, and show that this asymmetry can be used to reduce the technical requirements of experimental setups intended to demonstrate the EPR paradox. Furthermore, we develop a more stringent steering inequality that is symmetric between parties, and use it to show that the down-converted photon pairs also exhibit symmetric EPR steering.

Violation of Continuous-Variable Einstein-Podolsky-Rosen Steering with Discrete Measurements

NASA Astrophysics Data System (ADS)

Schneeloch, James; Dixon, P. Ben; Howland, Gregory A.; Broadbent, Curtis J.; Howell, John C.

2013-03-01

In this Letter, we derive an entropic Einstein-Podolsky-Rosen (EPR) steering inequality for continuous-variable systems using only experimentally measured discrete probability distributions and details of the measurement apparatus. We use this inequality to witness EPR steering between the positions and momenta of photon pairs generated in spontaneous parametric down-conversion. We examine the asymmetry between parties in this inequality, and show that this asymmetry can be used to reduce the technical requirements of experimental setups intended to demonstrate the EPR paradox. Furthermore, we develop a more stringent steering inequality that is symmetric between parties, and use it to show that the down-converted photon pairs also exhibit symmetric EPR steering.

Greener, meaner diesels sport thermal barrier coatings

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

Winkler, M.F.; Parker, D.W.

1992-05-01

The highly reliable diesel engine has long been the workhorse of the transportation, industrial power, utility, and marine industries. Demand for diesels is expected to accelerate well into the next century, driven by the engine's ability to economically produce power in almost any environment. Increasingly stringent environmental, efficiency, and durability requirements, however, present new challenges to diesel engine manufacturers and operators. This paper reports that many of these challenges can be met entirely, or in part, by thermal barrier coatings (TBCs). Diesel engine TBCs are plasma-spray-applied ceramics, which insulate combustion system components, such as pistons, valves, and piston fire decks,more » from heat and thermal shock.« less

Design, qualification, manufacturing and integration of IXV Ablative Thermal Protection System

NASA Astrophysics Data System (ADS)

Cioeta, Mario; Di Vita, Gandolfo; Signorelli Maria, Teresa; Bianco, Gianluca; Cutroni, Maurizio; Damiani, Francesco; Ferretti, Viviana; Rotondo, Adriano

2016-07-01

In the present paper, all the activities carried out by Avio S.p.A in order to define, qualify, manufacture and integrate the IXV Ablative TPS will be presented. In particular the extensive numerical simulation in both small and full scale testing activities will be overviewed. Wide-ranging testing activity has been carried out in order to verify, confirm and correlate the numerical models used for TPS sizing. Tests ranged from classical thermo-mechanical characterization traction specimens to tests in plasma wind tunnels on dedicated prototypes. Finally manufacturing and integration activities will be described emphasizing technological aspects solved in order to meet the stringent requirements in terms of shape accuracy and integration tolerances.

Design and testing of the Space Station Freedom Propellant Tank Assembly

NASA Technical Reports Server (NTRS)

Dudley, D. D.; Thonet, T. A.; Goforth, A. M.

1992-01-01

Propellant storage and management functions for the Propulsion Module of the U.S. Space Station Freedom are provided by the Propellant Tank Assembly (PTA). The PTA consists of a surface-tension type propellant acquisition device contained within a welded titanium pressure vessel. The PTA design concept was selected with high reliability and low program risk as primary goals in order to meet stringent NASA structural, expulsion, fracture control and reliability requirements. The PTA design makes use of Shuttle Orbital Maneuvering System and Peacekeeper Propellant Storage Assembly design and analysis techniques. This paper summarizes the PTA design solution and discusses the underlying detailed analyses. In addition, design verification and qualification test activities are discussed.

Reliability of unstable periodic orbit based control strategies in biological systems

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

Mishra, Nagender; Singh, Harinder P.; Hasse, Maria

2015-04-15

Presence of recurrent and statistically significant unstable periodic orbits (UPOs) in time series obtained from biological systems is now routinely used as evidence for low dimensional chaos. Extracting accurate dynamical information from the detected UPO trajectories is vital for successful control strategies that either aim to stabilize the system near the fixed point or steer the system away from the periodic orbits. A hybrid UPO detection method from return maps that combines topological recurrence criterion, matrix fit algorithm, and stringent criterion for fixed point location gives accurate and statistically significant UPOs even in the presence of significant noise. Geometry ofmore » the return map, frequency of UPOs visiting the same trajectory, length of the data set, strength of the noise, and degree of nonstationarity affect the efficacy of the proposed method. Results suggest that establishing determinism from unambiguous UPO detection is often possible in short data sets with significant noise, but derived dynamical properties are rarely accurate and adequate for controlling the dynamics around these UPOs. A repeat chaos control experiment on epileptic hippocampal slices through more stringent control strategy and adaptive UPO tracking is reinterpreted in this context through simulation of similar control experiments on an analogous but stochastic computer model of epileptic brain slices. Reproduction of equivalent results suggests that far more stringent criteria are needed for linking apparent success of control in such experiments with possible determinism in the underlying dynamics.« less

76 FR 75913 - Notice of Lodging of Modification of Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-05

... (``Regulated Bacteria'') and to comply with interim effluent limitations for those pollutants. The proposed Modification provides new, more stringent interim effluent limitations for Regulated Bacteria and requires... effluent limitations for Regulated Bacteria set forth in the Facility's National Pollutant Discharge...

42 CFR 455.452 - Other State screening methods.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 4 2013-10-01 2013-10-01 false Other State screening methods. 455.452 Section 455....452 Other State screening methods. Nothing in this subpart must restrict the State Medicaid agency from establishing provider screening methods in addition to or more stringent than those required by...

42 CFR 455.452 - Other State screening methods.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 4 2011-10-01 2011-10-01 false Other State screening methods. 455.452 Section 455....452 Other State screening methods. Nothing in this subpart must restrict the State Medicaid agency from establishing provider screening methods in addition to or more stringent than those required by...

49 CFR 383.133 - Testing methods.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Testing methods. 383.133 Section 383.133... STANDARDS; REQUIREMENTS AND PENALTIES Tests § 383.133 Testing methods. (a) All tests shall be constructed in... must be at least as stringent as the Federal standards. (c) States shall determine specific methods for...

FY 2001 Pollution Prevention/Compliance, Acquisition and Technology Division Annual Report

DTIC Science & Technology

2002-02-15

readiness, save money and avoid bad decisions by knowing which alternative cleaning products meet its stringent requirements for performance, soldier...several cleaning products and gather data the Army and other DoD services can use to make procurement and usage decisions. The current program test

Fixed-Abrasive Grinding of Thin-Film Recording Heads Final Report CRADA No. TC-0498-93

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

Blaedel, K. L.; Newman, C.

The goals of this project were (1) to significantly reduce the cost of manufacturing thin-film recording heads for magnetic storage media and (2) to meet the stringent dimensional tolerances required for heads in the next generation high-density disc drives.

Evidence-Based Practices in Mentoring Students with Disabilities: Four Case Studies

ERIC Educational Resources Information Center

Stumbo, Norma J.; Martin, Jay K.; Nordstrom, Dan; Rolfe, Tina; Burgstahler, Sheryl; Whitney, Jean; Langley-Turnbaugh, Samantha; Lovewell, Lynn; Moeller, Babette; Larry, Randy; Misquez, Ed

2011-01-01

Individuals with disabilities are attending postsecondary institutions at higher rates than ever before, although many struggle to adjust in college environments. On one hand, higher education positively correlates with better employment outcomes, while on the other, higher education represents more stringent academic requirements and more…

Live, Online Short-Courses: A Case Study of Innovative Teacher Professional Development

ERIC Educational Resources Information Center

Marrero, Meghan E.; Woodruff, Karen A.; Schuster, Glen S.; Riccio, Jessica Fitzsimons

2010-01-01

Teachers are searching for new venues through which they may meet stringent professional development requirements. Under competitive funding from NASA's (National Aeronautics and Space Administration) Office of Education and the NASA Explorer Schools Project, U.S. Satellite Laboratory, Inc. created a series of live, online, interactive…

Documentation of 50% water conservation in a single process at a beef abattoir

USDA-ARS?s Scientific Manuscript database

Beef slaughter is water intensive due to stringent food safety requirements. We conducted a study at a commercial beef processor to demonstrate water conservation by modifying the mechanical head wash. We documented the initial nozzle configuration (112 nozzles), water pressure (275 kPa), and flowra...

7 CFR 331.5 - Exemptions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... reported to APHIS or CDC by telephone, facsimile, or e-mail. This report must be followed by submission of APHIS/CDC Form 4 within 7 calendar days after identification. Less stringent reporting may be required during agricultural emergencies or outbreaks, or in endemic areas. A copy of APHIS/CDC Form 4 must be...

7 CFR 331.5 - Exemptions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... reported to APHIS or CDC by telephone, facsimile, or e-mail. This report must be followed by submission of APHIS/CDC Form 4 within 7 calendar days after identification. Less stringent reporting may be required during agricultural emergencies or outbreaks, or in endemic areas. A copy of APHIS/CDC Form 4 must be...

7 CFR 331.5 - Exemptions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... reported to APHIS or CDC by telephone, facsimile, or e-mail. This report must be followed by submission of APHIS/CDC Form 4 within 7 calendar days after identification. Less stringent reporting may be required during agricultural emergencies or outbreaks, or in endemic areas. A copy of APHIS/CDC Form 4 must be...

7 CFR 331.5 - Exemptions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... reported to APHIS or CDC by telephone, facsimile, or e-mail. This report must be followed by submission of APHIS/CDC Form 4 within 7 calendar days after identification. Less stringent reporting may be required during agricultural emergencies or outbreaks, or in endemic areas. A copy of APHIS/CDC Form 4 must be...

7 CFR 331.5 - Exemptions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... reported to APHIS or CDC by telephone, facsimile, or e-mail. This report must be followed by submission of APHIS/CDC Form 4 within 7 calendar days after identification. Less stringent reporting may be required during agricultural emergencies or outbreaks, or in endemic areas. A copy of APHIS/CDC Form 4 must be...

49 CFR 661.21 - State Buy America provisions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 7 2010-10-01 2010-10-01 false State Buy America provisions. 661.21 Section 661... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BUY AMERICA REQUIREMENTS § 661.21 State Buy America provisions. (a) Except as provided in paragraph (b) of this section, any State may impose more stringent Buy America or...

49 CFR 661.21 - State Buy America provisions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 7 2014-10-01 2014-10-01 false State Buy America provisions. 661.21 Section 661... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BUY AMERICA REQUIREMENTS § 661.21 State Buy America provisions. (a) Except as provided in paragraph (b) of this section, any State may impose more stringent Buy America or...

49 CFR 661.21 - State Buy America provisions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 7 2011-10-01 2011-10-01 false State Buy America provisions. 661.21 Section 661... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BUY AMERICA REQUIREMENTS § 661.21 State Buy America provisions. (a) Except as provided in paragraph (b) of this section, any State may impose more stringent Buy America or...

49 CFR 661.21 - State Buy America provisions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 7 2012-10-01 2012-10-01 false State Buy America provisions. 661.21 Section 661... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BUY AMERICA REQUIREMENTS § 661.21 State Buy America provisions. (a) Except as provided in paragraph (b) of this section, any State may impose more stringent Buy America or...

49 CFR 661.21 - State Buy America provisions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 7 2013-10-01 2013-10-01 false State Buy America provisions. 661.21 Section 661... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BUY AMERICA REQUIREMENTS § 661.21 State Buy America provisions. (a) Except as provided in paragraph (b) of this section, any State may impose more stringent Buy America or...

30 CFR 903.700 - Arizona Federal program.

Code of Federal Regulations, 2014 CFR

2014-07-01

... operations in Arizona conducted on non-Federal and non-Indian lands. To the extent required by 30 CFR part 740, this part also applies to surface coal mining and reclamation operations on Federal lands in... that the rules in this chapter establish more stringent environmental or land use controls: (1) The...

30 CFR 903.700 - Arizona Federal program.

Code of Federal Regulations, 2012 CFR

2012-07-01

... operations in Arizona conducted on non-Federal and non-Indian lands. To the extent required by 30 CFR part 740, this part also applies to surface coal mining and reclamation operations on Federal lands in... that the rules in this chapter establish more stringent environmental or land use controls: (1) The...

30 CFR 903.700 - Arizona Federal program.

Code of Federal Regulations, 2011 CFR

2011-07-01

... operations in Arizona conducted on non-Federal and non-Indian lands. To the extent required by 30 CFR part 740, this part also applies to surface coal mining and reclamation operations on Federal lands in... that the rules in this chapter establish more stringent environmental or land use controls: (1) The...

30 CFR 903.700 - Arizona Federal program.

Code of Federal Regulations, 2013 CFR

2013-07-01

... operations in Arizona conducted on non-Federal and non-Indian lands. To the extent required by 30 CFR part 740, this part also applies to surface coal mining and reclamation operations on Federal lands in... that the rules in this chapter establish more stringent environmental or land use controls: (1) The...

NFIRAOS in 2015: engineering for future integration of complex subsystems

NASA Astrophysics Data System (ADS)

Atwood, Jenny; Andersen, David; Byrnes, Peter; Densmore, Adam; Fitzsimmons, Joeleff; Herriot, Glen; Hill, Alexis

2016-07-01

The Narrow Field InfraRed Adaptive Optics System (NFIRAOS) will be the first-light facility Adaptive Optics (AO) system for the Thirty Meter Telescope (TMT). NFIRAOS will be able to host three science instruments that can take advantage of this high performance system. NRC Herzberg is leading the design effort for this critical TMT subsystem. As part of the final design phase of NFIRAOS, we have identified multiple subsystems to be sub-contracted to Canadian industry. The scope of work for each subcontract is guided by the NFIRAOS Work Breakdown Structure (WBS) and is divided into two phases: the completion of the final design and the fabrication, assembly and delivery of the final product. Integration of the subsystems at NRC will require a detailed understanding of the interfaces between the subsystems, and this work has begun by defining the interface physical characteristics, stability, local coordinate systems, and alignment features. In order to maintain our stringent performance requirements, the interface parameters for each subsystem are captured in multiple performance budgets, which allow a bottom-up error estimate. In this paper we discuss our approach for defining the interfaces in a consistent manner and present an example error budget that is influenced by multiple subsystems.

Field Testing of Compartmentalization Methods for Multifamily Construction

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

Ueno, K.; Lstiburek, J. W.

2015-03-01

The 2012 International Energy Conservation Code (IECC) has an airtightness requirement of 3 air changes per hour at 50 Pascals test pressure (3 ACH50) for single-family and multifamily construction (in climate zones 3–8). The Leadership in Energy & Environmental Design certification program and ASHRAE Standard 189 have comparable compartmentalization requirements. ASHRAE Standard 62.2 will soon be responsible for all multifamily ventilation requirements (low rise and high rise); it has an exceptionally stringent compartmentalization requirement. These code and program requirements are driving the need for easier and more effective methods of compartmentalization in multifamily buildings.

Abatement of tropospheric ozone: effects of strategies to improve air quality on public health and other sectors.

PubMed

Guest, C S; Morgan, P; Moss, J R; Woodward, A J; McMichael, A J

1996-06-01

The National Health and Medical Research Council's air quality goal for ozone in the troposphere (near the earth's surface) is 0.12 parts per million (ppm), averaged over one hour, similar to the United States standard, but less stringent than the guideline for Europe. We aimed to identify the environmental, economic and social changes that would be associated with changing the goal. Methods included literature review, economic assessments and group interviews. The group to benefit from lower exposures may include outdoor workers, school children and people not in regular day-time work indoors, because ozone is most prevalent during the daylight hours of the warmer months. A lower level could improve the yield of some crops. The causes and effects of tropospheric ozone are not appreciated except among groups with relevant commercial, industrial or scientific experience. However, the consultations identified frustration about the social problems caused by dependence on private motor vehicles. Short-term costs of compliance with a more stringent goal would fall principally on the users of transport. The value of the benefits was enough for many to support making the ozone goal more stringent, but those who required a demonstration of financial benefit (even including savings of health care costs) did not support any change to the goal. Based primarily on averted detriment to health, we recommend the more stringent level of 0.08 ppm (one-hour average) as the goal for the year 2005 in Australia and elsewhere. The addition of a goal with longer averaging time is also proposed.

40 CFR 35.2015 - State priority system and project priority list.

Code of Federal Regulations, 2014 CFR

2014-07-01

... I); (B) Treatment more stringent than secondary (category II); (C) Infiltration/inflow correction... cost-effective alternative; (C) New interceptors and appurtenances; and (D) Infiltration/inflow...

40 CFR 35.2015 - State priority system and project priority list.

Code of Federal Regulations, 2013 CFR

2013-07-01

... I); (B) Treatment more stringent than secondary (category II); (C) Infiltration/inflow correction... cost-effective alternative; (C) New interceptors and appurtenances; and (D) Infiltration/inflow...

40 CFR 35.2015 - State priority system and project priority list.

Code of Federal Regulations, 2011 CFR

2011-07-01

... I); (B) Treatment more stringent than secondary (category II); (C) Infiltration/inflow correction... cost-effective alternative; (C) New interceptors and appurtenances; and (D) Infiltration/inflow...

40 CFR 35.2015 - State priority system and project priority list.

Code of Federal Regulations, 2012 CFR

2012-07-01

... I); (B) Treatment more stringent than secondary (category II); (C) Infiltration/inflow correction... cost-effective alternative; (C) New interceptors and appurtenances; and (D) Infiltration/inflow...

Carbon monoxide exposure from aircraft fueling vehicles.

PubMed

McCammon, C S; Halperin, W F; Lemen, R A

1981-01-01

Investigators from the National Institute for Occupational Safety and Health observed deficiencies in maintenance of fueling trucks at an international airport. The exhaust system is vented under the front bumper, a standard design on fueling trucks which is intended to minimize the proximity of the exhaust system to the jet fuel in the vehicles. Carbon monoxide levels were measured in the cabs of 17 fueling trucks with windows closed, heaters on, and in different positions relative to the wind. One truck had an average CO level of 300 ppm, two exceeded 100 ppm, five others exceeded 50 ppm, while levels in the other nine averaged less than or equal to 500 ppm. Levels of CO depended on the mechanical condition of the vehicle and the vehicle's orientation to the wind. Stringent maintenance is required as the exhaust design is not fail-safe.

Spacecraft attitude determination using a second-order nonlinear filter

NASA Technical Reports Server (NTRS)

Vathsal, S.

1987-01-01

The stringent attitude determination accuracy and faster slew maneuver requirements demanded by present-day spacecraft control systems motivate the development of recursive nonlinear filters for attitude estimation. This paper presents the second-order filter development for the estimation of attitude quaternion using three-axis gyro and star tracker measurement data. Performance comparisons have been made by computer simulation of system models and filter mechanization. It is shown that the second-order filter consistently performs better than the extended Kalman filter when the performance index of the root sum square estimation error of the quaternion vector is compared. The second-order filter identifies the gyro drift rates faster than the extended Kalman filter. The uniqueness of this algorithm is the online generation of the time-varying process and measurement noise covariance matrices, derived as a function or the process and measurement nonlinearity, respectively.

Histone modifications controlling native and induced neural stem cell identity.

PubMed

Broccoli, Vania; Colasante, Gaia; Sessa, Alessandro; Rubio, Alicia

2015-10-01

During development, neural progenitor cells (NPCs) that are capable of self-renewing maintain a proliferative cellular pool while generating all differentiated neural cell components. Although the genetic network of transcription factors (TFs) required for neural specification has been well characterized, the unique set of histone modifications that accompanies this process has only recently started to be investigated. In vitro neural differentiation of pluripotent stem cells is emerging as a powerful system to examine epigenetic programs. Deciphering the histone code and how it shapes the chromatin environment will reveal the intimate link between epigenetic changes and mechanisms for neural fate determination in the developing nervous system. Furthermore, it will offer a molecular framework for a stringent comparison between native and induced neural stem cells (iNSCs) generated by direct neural cell conversion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Monitoring xenon purity in the LUX detector with a mass spectrometry system

NASA Astrophysics Data System (ADS)

Balajthy, Jon; LUX Experiment Collaboration

2015-04-01

The LUX dark matter search experiment is a 350 kg two-phase liquid/gas xenon time projection chamber located at the 4850 ft level of the Sanford Underground Research Facility in Lead, SD. To monitor for radioactive impurities such as krypton and impurities which limit charge yield such as oxygen, LUX uses a xenon sampling system consisting of a mass spectrometer and a liquid nitrogen cold trap. The cold trap separates the gaseous impurities from a small sample of xenon and allows them to pass to the mass spectrometer for analysis. We report here on results from the LUX xenon sampling program. We also report on methods to enhance the sensitivity of the cold trap technique in preparation for the next-generation LUX-ZEPLIN experiment which will have even more stringent purity requirements.

Marshall Space Flight Center's Solar Wind Facility

NASA Technical Reports Server (NTRS)

Wright, K. H.; Schneider, T. A.; Vaughn, J. A.; Whittlesey, P. L.

2017-01-01

Historically, NASA's Marshall Space Flight Center (MSFC) has operated a Solar Wind Facility (SWF) to provide long term particle and photon exposure to material samples. The requirements on the particle beam details were not stringent as the cumulative fluence level is the test goal. Motivated by development of the faraday cup instrument on the NASA Solar Probe Plus (SPP) mission, the MSFC SWF has been upgraded to included high fidelity particle beams providing broadbeam ions, broadbeam electrons, and narrow beam protons or ions, which cover a wide dynamic range of solar wind velocity and flux conditions. The large vacuum chamber with integrated cryo-shroud, combined with a 3-axis positioning system, provides an excellent platform for sensor development and qualification. This short paper provides some details of the SWF charged particle beams characteristics in the context of the Solar Probe Plus program requirements. Data will be presented on the flux and energy ranges as well as beam stability.

Parallelization of implicit finite difference schemes in computational fluid dynamics

NASA Technical Reports Server (NTRS)

Decker, Naomi H.; Naik, Vijay K.; Nicoules, Michel

1990-01-01

Implicit finite difference schemes are often the preferred numerical schemes in computational fluid dynamics, requiring less stringent stability bounds than the explicit schemes. Each iteration in an implicit scheme involves global data dependencies in the form of second and higher order recurrences. Efficient parallel implementations of such iterative methods are considerably more difficult and non-intuitive. The parallelization of the implicit schemes that are used for solving the Euler and the thin layer Navier-Stokes equations and that require inversions of large linear systems in the form of block tri-diagonal and/or block penta-diagonal matrices is discussed. Three-dimensional cases are emphasized and schemes that minimize the total execution time are presented. Partitioning and scheduling schemes for alleviating the effects of the global data dependencies are described. An analysis of the communication and the computation aspects of these methods is presented. The effect of the boundary conditions on the parallel schemes is also discussed.

Fuel processing requirements and techniques for fuel cell propulsion power

NASA Astrophysics Data System (ADS)

Kumar, R.; Ahmed, S.; Yu, M.

Fuels for fuel cells in transportation systems are likely to be methanol, natural gas, hydrogen, propane, or ethanol. Fuels other than hydrogen will need to be reformed to hydrogen on-board the vehicle. The fuel reformer must meet stringent requirements for weight and volume, product quality, and transient operation. It must be compact and lightweight, must produce low levels of CO and other byproducts, and must have rapid start-up and good dynamic response. Catalytic steam reforming, catalytic or noncatalytic partial oxidation reforming, or some combination of these processes may be used. This paper discusses salient features of the different kinds of reformers and describes the catalysts and processes being examined for the oxidation reforming of methanol and the steam reforming of ethanol. Effective catalysts and reaction conditions for the former have been identified; promising catalysts and reaction conditions for the latter are being investigated.

Nutation and precession control of the High Energy Solar Physics (HESP) satellite

NASA Technical Reports Server (NTRS)

Jayaraman, C. P.; Robertson, B. P.

1993-01-01

The High Energy Solar Physics (HESP) spacecraft is an intermediate class satellite proposed by NASA to study solar high-energy phenomena during the next cycle of high solar activity in the 1998 to 2005 time frame. The HESP spacecraft is a spinning satellite which points to the sun with stringent pointing requirements. The natural dynamics of a spinning satellite includes an undesirable effect: nutation, which is due to the presence of disturbances and offsets of the spin axis from the angular momentum vector. The proposed Attitude Control System (ACS) attenuates nutation with reaction wheels. Precessing the spacecraft to track the sun in the north-south and east-west directions is accomplished with the use of torques from magnetic torquer bars. In this paper, the basic dynamics of a spinning spacecraft are derived, control algorithms to meet HESP science requirements are discussed and simulation results to demonstrate feasibility of the ACS concept are presented.

Global Rsh-dependent transcription profile of Brucella suis during stringent response unravels adaptation to nutrient starvation and cross-talk with other stress responses

PubMed Central

2013-01-01

Background In the intracellular pathogen Brucella spp., the activation of the stringent response, a global regulatory network providing rapid adaptation to growth-affecting stress conditions such as nutrient deficiency, is essential for replication in the host. A single, bi-functional enzyme Rsh catalyzes synthesis and hydrolysis of the alarmone (p)ppGpp, responsible for differential gene expression under stringent conditions. Results cDNA microarray analysis allowed characterization of the transcriptional profiles of the B. suis 1330 wild-type and Δrsh mutant in a minimal medium, partially mimicking the nutrient-poor intramacrophagic environment. A total of 379 genes (11.6% of the genome) were differentially expressed in a rsh-dependent manner, of which 198 were up-, and 181 were down-regulated. The pleiotropic character of the response was confirmed, as the genes encoded an important number of transcriptional regulators, cell envelope proteins, stress factors, transport systems, and energy metabolism proteins. Virulence genes such as narG and sodC, respectively encoding respiratory nitrate reductase and superoxide dismutase, were under the positive control of (p)ppGpp, as well as expression of the cbb3-type cytochrome c oxidase, essential for chronic murine infection. Methionine was the only amino acid whose biosynthesis was absolutely dependent on stringent response in B. suis. Conclusions The study illustrated the complexity of the processes involved in adaptation to nutrient starvation, and contributed to a better understanding of the correlation between stringent response and Brucella virulence. Most interestingly, it clearly indicated (p)ppGpp-dependent cross-talk between at least three stress responses playing a central role in Brucella adaptation to the host: nutrient, oxidative, and low-oxygen stress. PMID:23834488

Reliable vision-guided grasping

NASA Technical Reports Server (NTRS)

Nicewarner, Keith E.; Kelley, Robert B.

1992-01-01

Automated assembly of truss structures in space requires vision-guided servoing for grasping a strut when its position and orientation are uncertain. This paper presents a methodology for efficient and robust vision-guided robot grasping alignment. The vision-guided grasping problem is related to vision-guided 'docking' problems. It differs from other hand-in-eye visual servoing problems, such as tracking, in that the distance from the target is a relevant servo parameter. The methodology described in this paper is hierarchy of levels in which the vision/robot interface is decreasingly 'intelligent,' and increasingly fast. Speed is achieved primarily by information reduction. This reduction exploits the use of region-of-interest windows in the image plane and feature motion prediction. These reductions invariably require stringent assumptions about the image. Therefore, at a higher level, these assumptions are verified using slower, more reliable methods. This hierarchy provides for robust error recovery in that when a lower-level routine fails, the next-higher routine will be called and so on. A working system is described which visually aligns a robot to grasp a cylindrical strut. The system uses a single camera mounted on the end effector of a robot and requires only crude calibration parameters. The grasping procedure is fast and reliable, with a multi-level error recovery system.

Investigation of Cleanliness Verification Techniques for Rocket Engine Hardware

NASA Technical Reports Server (NTRS)

Fritzemeier, Marilyn L.; Skowronski, Raymund P.

1994-01-01

Oxidizer propellant systems for liquid-fueled rocket engines must meet stringent cleanliness requirements for particulate and nonvolatile residue. These requirements were established to limit residual contaminants which could block small orifices or ignite in the oxidizer system during engine operation. Limiting organic residues in high pressure oxygen systems, such as in the Space Shuttle Main Engine (SSME), is particularly important. The current method of cleanliness verification for the SSME uses an organic solvent flush of the critical hardware surfaces. The solvent is filtered and analyzed for particulate matter followed by gravimetric determination of the nonvolatile residue (NVR) content of the filtered solvent. The organic solvents currently specified for use (1, 1, 1-trichloroethane and CFC-113) are ozone-depleting chemicals slated for elimination by December 1995. A test program is in progress to evaluate alternative methods for cleanliness verification that do not require the use of ozone-depleting chemicals and that minimize or eliminate the use of solvents regulated as hazardous air pollutants or smog precursors. Initial results from the laboratory test program to evaluate aqueous-based methods and organic solvent flush methods for NVR verification are provided and compared with results obtained using the current method. Evaluation of the alternative methods was conducted using a range of contaminants encountered in the manufacture of rocket engine hardware.

The Implications of Deep Mitigation Pathways

NASA Astrophysics Data System (ADS)

Calvin, K. V.

2016-12-01

The 21st Conference of Parties to the UNFCCC agreement called for limiting climate change to "well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C." A climate target of 1.5°C places a stringent constraint on allowable emissions over the twenty-first century. Roegli et al. (2015) set that constraint at 200-415 GtCO2 between 2011 and 2100 for a likely chance of staying below 1.5°C in 2100. Limiting emissions to these levels requires that global emissions peak and decline over the coming decades, with net negative global emissions by mid-century. This level of decarbonization requires dramatic shifts in the energy and agricultural sectors, and comes at significant economic costs. This talk explores the effect of mitigating climate change to 1.5°C on the economy, energy system, and terrestrial system. We quantify the required deployment of various low carbon technologies, as well as the amount of existing capital that is abandoned in an effort to limit emissions. We show the shifts required in the terrestrial system, including its contribution to carbon sequestration through afforestation and bioenergy. Additionally, we show the implications of deep mitigation pathways on energy, food, and carbon prices. We contrast these results with a reference, no climate policy, world and a 2°C.

Cyber Safety and Security for Reduced Crew Operations (RCO)

NASA Technical Reports Server (NTRS)

Driscoll, Kevin

2017-01-01

NASA and the Aviation Industry is looking into reduced crew operations (RCO) that would cut today's required two-person flight crews down to a single pilot with support from ground-based crews. Shared responsibility across air and ground personnel will require highly reliable and secure data communication and supporting automation, which will be safety-critical for passenger and cargo aircraft. This paper looks at the different types and degrees of authority delegation given from the air to the ground and the ramifications of each, including the safety and security hazards introduced, the mitigation mechanisms for these hazards, and other demands on an RCO system architecture which would be highly invasive into (almost) all safety-critical avionics. The adjacent fields of unmanned aerial systems and autonomous ground vehicles are viewed to find problems that RCO may face and related aviation accident scenarios are described. The paper explores possible data communication architectures to meet stringent performance and information security (INFOSEC) requirements of RCO. Subsequently, potential challenges for RCO data communication authentication, encryption and non-repudiation are identified. The approach includes a comprehensive safety-hazard analysis of the RCO system to determine top level INFOSEC requirements for RCO and proposes an option for effective RCO implementation. This paper concludes with questioning the economic viability of RCO in light of the expense of overcoming the operational safety and security hazards it would introduce.

Optical calibration of SNO +

NASA Astrophysics Data System (ADS)

Leming, Edward; SNO+ Collaboration

2015-04-01

Situated 2 km underground in Sudbury, Northern Ontario, the SNO + detector consists of an acrylic sphere 12 m in diameter containing 780 tons of target mass, surrounded by approximately 9,500 PMTs. For SNO, this target mass was heavy water, however the change to SNO + is defined by the change of this target mass to a novel scintillator. With the lower energy threshold, low intrinsic radioactivity levels and the best shielding against muons and cosmogenic activation of all existing neutrino experiments, SNO + will be sensitive to exciting new physics. The experiment will be studying solar, reactor, super nova and geo-neutrinos, though the main purpose of SNO + is the search for neutrinoless double-beta decay of Te-130. To meet the requirements imposed by the physics on detector performance, a detailed optical calibration is needed. Source deployment must be kept to a minimum and eliminated if possible, in order to meet the stringent radiopurity requirements. This led to the development of the Embedded LED/laser Light Injection Entity (ELLIE) system. This talk provides a summary of the upgrades to from SNO to SNO +, discussing the requirements on and methods of optical calibration, focusing on the deployed laserball and ELLIE system.

Lipophilic super-absorbent swelling gels as cleaners for use on weapons systems and platforms

USDA-ARS?s Scientific Manuscript database

Increasingly stringent environmental regulations on volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) demand the development of disruptive technologies for cleaning weapons systems and platforms. Currently employed techniques such as vapor degreasing, solvent, aqueous, or blast c...

Polybrominated diphenyl ether (PBDE) concentrations and resulting exposure in homes in California: relationships among passive air, surface wipe and dust concentrations, and temporal variability

EPA Science Inventory

Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in furniture foam, electronics, and other home furnishings. A field study was conducted that enrolled 139 households from California, which has had more stringent flame retardant requirements than other countries...

Sensitivity and Specificity of Proposed DSM-5 Criteria for Autism Spectrum Disorder in Toddlers

ERIC Educational Resources Information Center

Barton, Marianne L.; Robins, Diana L.; Jashar, Dasal; Brennan, Laura; Fein, Deborah

2013-01-01

Autism spectrum disorder (ASD) diagnosis is based on behavioral presentation; changes in conceptual models or defining behaviors may significantly impact diagnosis and uptake of ASD-specific interventions. The literature examining impact of DSM-5 criteria is equivocal. Toddlers may be especially vulnerable to the stringent requirements of…

Electrophoresis for biological production

NASA Technical Reports Server (NTRS)

Mccreight, L. R.

1977-01-01

Preparative electrophoresis may provide a unique method for meeting ever more stringent purity requirements. Prolonged near zero gravity in space may permit the operation of preparative electrophoresis equipment with 100 times greater throughput than is currently available. Some experiments with influenza Virus Antigen, Erythropoietin and Antihemophaliac Factor, along with process and economic projections, are briefly reviewed.

78 FR 56267 - Article 19-A of the State of New York's Vehicle and Traffic Law

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-12

... safety benefits, how it is being enforced against interstate passenger carriers and its effect, if any, on interstate commerce. DATES: Comments are due on or before November 12, 2013. ADDRESSES: You may... interstate commerce by imposing requirements that are more stringent than Federal regulations. MCC stated...

Parables and Politics: Clergy Attitudes toward Illegal Immigration in Alabama

ERIC Educational Resources Information Center

Wickersham, Mary Eleanor

2013-01-01

The passage of a stringent immigration law in Alabama in 2011 makes relevant the juxtaposition of clergy and congregant attitudes and behaviors toward illegal immigrants as related to Biblical teachings that require charity to aliens. In order to examine the relationship between religious attitudes and illegal immigration, approximately 426…

Making Academic OER Easy: Reflections on Technology and Openness at Oxford University

ERIC Educational Resources Information Center

Highton, Melissa; Fresen, Jill; Wild, Joanna

2011-01-01

Due to its stringent entry requirements, academic reputation and world ranking, Oxford University in the United Kingdom is perceived by some as being a closed, exclusive, and elitist institution. As learning technologists working in the institution, we have experienced an enthusiasm amongst academic colleagues for openness in publication and…

40 CFR 129.7 - Requirement and procedure for establishing a more stringent effluent limitation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION AGENCY (CONTINUED) WATER PROGRAMS TOXIC POLLUTANT EFFLUENT STANDARDS Toxic Pollutant Effluent...) determines that the ambient water criterion established in these standards is not being met or will not be met in the receiving water as a result of one or more discharges at levels allowed by these standards...

75 FR 48579 - Approval and Promulgation of Implementation Plans; State of Missouri

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-11

.... Louis area. The state has a statewide fugitive dust rule, 10 CSR 10-6.170, which contains similar... fugitive dust rule is as stringent as the requirements in the rescinded area rule and this action would not... longer in operation, and because the state's statewide fugitive dust rule contains similar restrictions...

40 CFR 146.15 - Class I municipal disposal well alternative authorization in certain parts of Florida.

Code of Federal Regulations, 2010 CFR

2010-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM... ground water monitoring data generated pursuant to regulatory requirements governing operation of Class I...-600.420(1)(d), and using high-level disinfection in a manner that is no less stringent than the...

40 CFR 146.15 - Class I municipal disposal well alternative authorization in certain parts of Florida.

Code of Federal Regulations, 2012 CFR

2012-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM... ground water monitoring data generated pursuant to regulatory requirements governing operation of Class I...-600.420(1)(d), and using high-level disinfection in a manner that is no less stringent than the...

40 CFR 146.15 - Class I municipal disposal well alternative authorization in certain parts of Florida.

Code of Federal Regulations, 2011 CFR

2011-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM... ground water monitoring data generated pursuant to regulatory requirements governing operation of Class I...-600.420(1)(d), and using high-level disinfection in a manner that is no less stringent than the...

40 CFR 146.15 - Class I municipal disposal well alternative authorization in certain parts of Florida.

Code of Federal Regulations, 2013 CFR

2013-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM... ground water monitoring data generated pursuant to regulatory requirements governing operation of Class I...-600.420(1)(d), and using high-level disinfection in a manner that is no less stringent than the...

40 CFR 146.15 - Class I municipal disposal well alternative authorization in certain parts of Florida.

Code of Federal Regulations, 2014 CFR

2014-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM... ground water monitoring data generated pursuant to regulatory requirements governing operation of Class I...-600.420(1)(d), and using high-level disinfection in a manner that is no less stringent than the...

77 FR 1895 - Revisions to the California State Implementation Plan, South Coast Air Quality Management District

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-12

... approve South Coast Air Quality Management District (SCAQMD) Rule 317, ``Clean Air Act Non- Attainment Fee... Rule 317, an equivalent alternative program, is not less stringent than the program required by section... equivalent alternative programs, and, if so, whether Rule 317 would constitute an approvable equivalent...

77 FR 74372 - Revisions to the California State Implementation Plan, South Coast Air Quality Management District

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-14

... of South Coast Air Quality Management District (SCAQMD) Rule 317, ``Clean Air Act Non- Attainment Fee... determined that SCAQMD's alternative fee-equivalent program is not less stringent than the program required by section 185, and, therefore, is approvable as an equivalent alternative program, consistent with...

76 FR 25569 - Defense Federal Acquisition Regulation Supplement; Minimizing the Use of Materials Containing...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-05

..., therefore, this action establishes requirements that DoD personnel must follow when making acquisitions for...) ten-fold from 52 to 5 micrograms-per-cubic-meter, making it among the most stringently regulated... officer will forward the request to the authorized approving official (DFARS 223.7305(a)) for decision...

Documentation of 50% water conservation in a single process at a beef abattoir. Meat Science

USDA-ARS?s Scientific Manuscript database

Beef slaughter is water intensive due to stringent food safety requirements. We conducted a study at a commercial beef processor to demonstrate water conservation by modifying the mechanical head wash. We documented the initial nozzle configuration (112 nozzles), water pressure (275 kPa), and flowra...

Precision requirements and innovative manufacturing for ultrahigh precision laser interferometry of gravitational-wave astronomy

NASA Astrophysics Data System (ADS)

Ni, Wei-Tou; Han, Sen; Jin, Tao

2016-11-01

With the LIGO announcement of the first direct detection of gravitational waves (GWs), the GW Astronomy was formally ushered into our age. After one-hundred years of theoretical investigation and fifty years of experimental endeavor, this is a historical landmark not just for physics and astronomy, but also for industry and manufacturing. The challenge and opportunity for industry is precision and innovative manufacturing in large size - production of large and homogeneous optical components, optical diagnosis of large components, high reflectance dielectric coating on large mirrors, manufacturing of components for ultrahigh vacuum of large volume, manufacturing of high attenuating vibration isolation system, production of high-power high-stability single-frequency lasers, production of high-resolution positioning systems etc. In this talk, we address the requirements and methods to satisfy these requirements. Optical diagnosis of large optical components requires large phase-shifting interferometer; the 1.06 μm Phase Shifting Interferometer for testing LIGO optics and the recently built 24" phase-shifting Interferometer in Chengdu, China are examples. High quality mirrors are crucial for laser interferometric GW detection, so as for ring laser gyroscope, high precision laser stabilization via optical cavities, quantum optomechanics, cavity quantum electrodynamics and vacuum birefringence measurement. There are stringent requirements on the substrate materials and coating methods. For cryogenic GW interferometer, appropriate coating on sapphire or silicon are required for good thermal and homogeneity properties. Large ultrahigh vacuum components and high attenuating vibration system together with an efficient metrology system are required and will be addressed. For space interferometry, drag-free technology and weak-light manipulation technology are must. Drag-free technology is well-developed. Weak-light phase locking is demonstrated in the laboratories while weak-light manipulation technology still needs developments.

Precision phase control for the radio frequency system of K500 superconducting cyclotron at Variable Energy Cyclotron Centre, Kolkata

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

Som, Sumit; Ghosh, Surajit; Seth, Sudeshna

2013-11-15

Variable Energy Cyclotron Centre (VECC) has commissioned K500 Superconducting cyclotron (SCC) based on MSU and Texas A and M university cyclotrons. The radio frequency (RF) system of SCC has been commissioned with the stringent requirement of various RF parameters. The three-phase RF system of Superconducting cyclotron has been developed in the frequency range 9–27 MHz with amplitude and phase stability of 100 ppm and ±0.1°, respectively. The phase control system has the option to change the relative phase difference between any two RF cavities and maintain the phase stability within ±0.1° during round-the-clock cyclotron operation. The said precision phase loopmore » consists of both analogue In-phase/Quadrature modulator to achieve faster response and also Direct Digital Synthesis based phase shifter to achieve wide dynamic range as well. This paper discusses detail insights into the various issues of phase control for the K500 SCC at VECC, Kolkata.« less

The many faces of competency.

PubMed

Drane, J F

1985-04-01

A sliding-scale model for assessing patient competency to consent to medical treatments is proposed. The least stringent standard, to be applied in the case of safe and effective treatments, assumes a valid consent if the patient is aware of what is happening and assents to the rational expectations of the physician. The second standard, applicable in the case of less certain treatments, requires that the patient understand the treatment options and have the capacity to choose or reject a treatment based on a weighing of risks and benefits. The third and most stringent standard, reserved for very dangerous treatments, bases competence to consent on an appreciation of the implications of the medical information for the patient's life and on an ability to state the reasons for the decision in terms of the medical issues and the patient's personal values.

Emergency vehicle alert system (EVAS)

NASA Technical Reports Server (NTRS)

Reed, Bill; Crump, Roger; Harper, Warren; Myneni, Krishna

1995-01-01

The Emergency Vehicle Alert System (EVAS) program is sponsored by the NASA/MSFC Technology Utilization (TU) office. The program was conceived to support the needs of hearing impaired drivers. The objective of the program is to develop a low-cost, small device which can be located in a personal vehicle and warn the driver, via a visual means, of the approach of an emergency vehicle. Many different technologies might be developed for this purpose and each has its own advantages and drawbacks. The requirements for an acoustic detection system, appear to be pretty stringent and may not allow the development of a reliable, low-cost device in the near future. The problems include variations in the sirens between various types of emergency vehicles, distortions due to wind and surrounding objects, competing background noise, sophisticated signal processing requirements, and omni-directional coverage requirements. Another approach is to use a Radio Frequency (RF) signal between the Emergency Vehicle (EV) and the Personal Vehicle (PV). This approach requires a transmitter on each EV and a receiver in each PV, however it is virtually assured that a system can be developed which works. With this approach, the real technology issue is how to make a system work as inexpensively as possible. This report gives a brief summary of the EVAS program from its inception and concentrates on describing the activities that occurred during Phase 4. References 1-3 describe activities under Phases 1-3. In the fourth phase of the program, the major effort to be expended was in development of the microcontroller system for the PV, refinement of some system elements and packaging for demonstration purposes. An EVAS system was developed and demonstrated which used standard spread spectrum modems with minor modifications.

On-orbit calibration for star sensors without priori information.

PubMed

Zhang, Hao; Niu, Yanxiong; Lu, Jiazhen; Zhang, Chengfen; Yang, Yanqiang

2017-07-24

The star sensor is a prerequisite navigation device for a spacecraft. The on-orbit calibration is an essential guarantee for its operation performance. However, traditional calibration methods rely on ground information and are invalid without priori information. The uncertain on-orbit parameters will eventually influence the performance of guidance navigation and control system. In this paper, a novel calibration method without priori information for on-orbit star sensors is proposed. Firstly, the simplified back propagation neural network is designed for focal length and main point estimation along with system property evaluation, called coarse calibration. Then the unscented Kalman filter is adopted for the precise calibration of all parameters, including focal length, main point and distortion. The proposed method benefits from self-initialization and no attitude or preinstalled sensor parameter is required. Precise star sensor parameter estimation can be achieved without priori information, which is a significant improvement for on-orbit devices. Simulations and experiments results demonstrate that the calibration is easy for operation with high accuracy and robustness. The proposed method can satisfy the stringent requirement for most star sensors.

KSC Center Director Bridges accepts an ISO 9001 certification plaque from DNV

NASA Technical Reports Server (NTRS)

1998-01-01

Center Director Roy Bridges (right) displays the 2000th ISO Certificate Plaque he was given by Dalton Lyon (left) of Det Norske Veritas (DNV), Inc., an international ISO certification organization, at a ceremony at KSC. The plaque is a representation of the ISO 9001 certification awarded to KSC by DNV. ISO 9001 comprises the most detailed, comprehensive set of standard requirements for quality programs established by the International Standards Organization. The presentation followed a successful independent audit by DNV of the KSC Management System in May of this year. The third-party auditors examined about 20 elements of KSC's system, including management responsibility, design control, documentation, test and inspection, and corrective action procedures. DNV found that KSC met or exceeded the stringent quality standards in all areas. KSC will use this certification as a tool to improve an already world- class team. All NASA centers are required by NASA Administrator Daniel S. Goldin to be ISO 9001 registered by September 1999. NASA is the first federal agency to seek the quality certification.

Ares Launch Vehicles Lean Practices Case Study

NASA Technical Reports Server (NTRS)

Doreswamy, Rajiv; Self, Timothy A.

2007-01-01

The Ares launch vehicles team, managed by the Ares Projects Office (APO) at NASA Marshall Space Flight Center, has completed the Ares I Crew Launch Vehicle System Requirements Review and System Definition Review and early design work for the Ares V Cargo Launch Vehicle. This paper provides examples of how Lean Manufacturing, Kaizen events, and Six Sigma practices are helping APO deliver a new space transportation capability on time and within budget, while still meeting stringent technical requirements. For example, Lean philosophies have been applied to numerous process definition efforts and existing process improvement activities, including the Ares I-X test flight Certificate of Flight Readiness (CoFR) process, risk management process, and review board organization and processes. Ares executives learned Lean practices firsthand, making the team "smart buyers" during proposal reviews and instilling the team with a sense of what is meant by "value-added" activities. Since the goal of the APO is to field launch vehicles at a reasonable cost and on an ambitious schedule, adopting Lean philosophies and practices will be crucial to the Ares Project's long-term SUCCESS.

Initial closed operation of the CELSS Test Facility Engineering Development Unit

NASA Technical Reports Server (NTRS)

Kliss, M.; Blackwell, C.; Zografos, A.; Drews, M.; MacElroy, R.; McKenna, R.; Heyenga, A. G.

2003-01-01

As part of the NASA Advanced Life Support Flight Program, a Controlled Ecological Life Support System (CELSS) Test Facility Engineering Development Unit has been constructed and is undergoing initial operational testing at NASA Ames Research Center. The Engineering Development Unit (EDU) is a tightly closed, stringently controlled, ground-based testbed which provides a broad range of environmental conditions under which a variety of CELSS higher plant crops can be grown. Although the EDU was developed primarily to provide near-term engineering data and a realistic determination of the subsystem and system requirements necessary for the fabrication of a comparable flight unit, the EDU has also provided a means to evaluate plant crop productivity and physiology under controlled conditions. This paper describes the initial closed operational testing of the EDU, with emphasis on the hardware performance capabilities. Measured performance data during a 28-day closed operation period are compared with the specified functional requirements, and an example of inferring crop growth parameters from the test data is presented. Plans for future science and technology testing are also discussed. Published by Elsevier Science Ltd on behalf of COSPAR.

KSC-98pc909

NASA Image and Video Library

1998-08-11

Center Director Roy Bridges speaks to KSC employees at the ISO certification ceremony held at the Training Auditorium. Bridges was presented an ISO 9001 certificate and plaque awarded to KSC by Det Norske Veritas (DNV), Inc., an international ISO certification organization. ISO 9001 comprises the most detailed, comprehensive set of standard requirements for quality programs established by the International Standards Organization. The presentation followed a successful independent audit by DNV of the KSC Management System in May of this year. The third-party auditors examined about 20 elements of KSC's system, including management responsibility, design control, documentation, test and inspection, and corrective action procedures. DNV found that KSC met or exceeded the stringent quality standards in all areas. KSC will use this certification as a tool to improve an already worldclass team. All NASA centers are required by NASA Administrator Daniel S. Goldin to be ISO 9001 registered by September 1999. NASA is the first federal agency to seek the quality certification. Next to Bridges is Heidi Hollingsworth, with the Center for Independent Living, who uses American Sign Language for any hearing-impaired employees in the audience

VETA-1 x ray detection system

NASA Technical Reports Server (NTRS)

Podgorski, W. A.; Flanagan, Kathy A.; Freeman, Mark D.; Goddard, R. G.; Kellogg, Edwin M.; Norton, T. J.; Ouellette, J. P.; Roy, A. G.; Schwartz, Daniel A.

1992-01-01

The alignment and X-ray imaging performance of the Advanced X-ray Astrophysics Facility (AXAF) Verification Engineering Test Article-I (VETA-I) was measured by the VETA-I X-Ray Detection System (VXDS). The VXDS was based on the X-ray detection system utilized in the AXAF Technology Mirror Assembly (TMA) program, upgraded to meet the more stringent requirements of the VETA-I test program. The VXDS includes two types of X-ray detectors: (1) a High Resolution Imager (HRI) which provides X-ray imaging capabilities, and (2) sealed and flow proportional counters which, in conjunction with apertures of various types and precision translation stages, provide the most accurate measurement of VETA-I performance. Herein we give an overview of the VXDS hardware including X-ray detectors, translation stages, apertures, proportional counters and flow counter gas supply system and associated electronics. We also describe the installation of the VXDS into the Marshall Space Flight Center (MSFC) X-Ray Calibration Facility (XRCF). We discuss in detail the design and performance of those elements of the VXDS which have not been discussed elsewhere; translation systems, flow counter gas supply system, apertures and thermal monitoring system.

A novel and lightweight system to secure wireless medical sensor networks.

PubMed

He, Daojing; Chan, Sammy; Tang, Shaohua

2014-01-01

Wireless medical sensor networks (MSNs) are a key enabling technology in e-healthcare that allows the data of a patient's vital body parameters to be collected by the wearable or implantable biosensors. However, the security and privacy protection of the collected data is a major unsolved issue, with challenges coming from the stringent resource constraints of MSN devices, and the high demand for both security/privacy and practicality. In this paper, we propose a lightweight and secure system for MSNs. The system employs hash-chain based key updating mechanism and proxy-protected signature technique to achieve efficient secure transmission and fine-grained data access control. Furthermore, we extend the system to provide backward secrecy and privacy preservation. Our system only requires symmetric-key encryption/decryption and hash operations and is thus suitable for the low-power sensor nodes. This paper also reports the experimental results of the proposed system in a network of resource-limited motes and laptop PCs, which show its efficiency in practice. To the best of our knowledge, this is the first secure data transmission and access control system for MSNs until now.

Two-photon microscope for multisite microphotolysis of caged neurotransmitters in acute brain slices

PubMed Central

Losavio, Bradley E.; Iyer, Vijay; Saggau, Peter

2009-01-01

We developed a two-photon microscope optimized for physiologically manipulating single neurons through their postsynaptic receptors. The optical layout fulfills the stringent design criteria required for high-speed, high-resolution imaging in scattering brain tissue with minimal photodamage. We detail the practical compensation of spectral and temporal dispersion inherent in fast laser beam scanning with acousto-optic deflectors, as well as a set of biological protocols for visualizing nearly diffraction-limited structures and delivering physiological synaptic stimuli. The microscope clearly resolves dendritic spines and evokes electrophysiological transients in single neurons that are similar to endogenous responses. This system enables the study of multisynaptic integration and will assist our understanding of single neuron function and dendritic computation. PMID:20059271

Cryogenic Evaluation of an Advanced DC/DC Converter Module for Deep Space Applications

NASA Technical Reports Server (NTRS)

Elbuluk, Malik E.; Hammoud, Ahmad; Gerber, Scott S.; Patterson, Richard

2003-01-01

DC/DC converters are widely used in power management, conditioning, and control of space power systems. Deep space applications require electronics that withstand cryogenic temperature and meet a stringent radiation tolerance. In this work, the performance of an advanced, radiation-hardened (rad-hard) commercial DC/DC converter module was investigated at cryogenic temperatures. The converter was investigated in terms of its steady state and dynamic operations. The output voltage regulation, efficiency, terminal current ripple characteristics, and output voltage response to load changes were determined in the temperature range of 20 to -140 C. These parameters were obtained at various load levels and at different input voltages. The experimental procedures along with the results obtained on the investigated converter are presented and discussed.

Autonomous mine detection system (AMDS) neutralization payload module

NASA Astrophysics Data System (ADS)

Majerus, M.; Vanaman, R.; Wright, N.

2010-04-01

The Autonomous Mine Detection System (AMDS) program is developing a landmine and explosive hazards standoff detection, marking, and neutralization system for dismounted soldiers. The AMDS Capabilities Development Document (CDD) has identified the requirement to deploy three payload modules for small robotic platforms: mine detection and marking, explosives detection and marking, and neutralization. This paper addresses the neutralization payload module. There are a number of challenges that must be overcome for the neutralization payload module to be successfully integrated into AMDS. The neutralizer must meet stringent size, weight, and power (SWaP) requirements to be compatible with a small robot. The neutralizer must be effective against a broad threat, to include metal and plastic-cased Anti-Personnel (AP) and Anti-Tank (AT) landmines, explosive devices, and Unexploded Explosive Ordnance (UXO.) It must adapt to a variety of threat concealments, overburdens, and emplacement methods, to include soil, gravel, asphalt, and concrete. A unique neutralization technology is being investigated for adaptation to the AMDS Neutralization Module. This paper will describe review this technology and how the other two payload modules influence its design for minimizing SWaP. Recent modeling and experimental efforts will be included.

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

Buehler, Marc; Tartaglia, Michael; Tompkins, John

The Mu2e experiment at Fermilab is designed to explore charged lepton flavor violation by searching for muon-to-electron conversion. The magnetic field generated by a system of solenoids is crucial for Mu2e and requires accurate characterization to detect any flaws and to produce a detailed field map. Stringent physics goals are driving magnetic field specifications for the Mu2e solenoids. A field mapper is being designed, which will produce detailed magnetic field maps. The uniform field region of the spectrometer volume requires the highest level of precision (1 Gauss per 1 Tesla). During commissioning, multiple magnetic field maps will be generated tomore » verify proper alignment of all magnet coils, and to create the final magnetic field map. In order to design and build a precise field mapping system consisting of Hall and NRM probes, tolerances and precision for such a system need to be evaluated. In this paper we present a design for the Mu2e field mapping hardware, and discuss results from OPERA-3D simulations to specify parameters for Hall and NMR probes. We also present a fitting procedure for the analytical treatment of our expected magnetic measurements.« less

Reliability and availability evaluation of Wireless Sensor Networks for industrial applications.

PubMed

Silva, Ivanovitch; Guedes, Luiz Affonso; Portugal, Paulo; Vasques, Francisco

2012-01-01

Wireless Sensor Networks (WSN) currently represent the best candidate to be adopted as the communication solution for the last mile connection in process control and monitoring applications in industrial environments. Most of these applications have stringent dependability (reliability and availability) requirements, as a system failure may result in economic losses, put people in danger or lead to environmental damages. Among the different type of faults that can lead to a system failure, permanent faults on network devices have a major impact. They can hamper communications over long periods of time and consequently disturb, or even disable, control algorithms. The lack of a structured approach enabling the evaluation of permanent faults, prevents system designers to optimize decisions that minimize these occurrences. In this work we propose a methodology based on an automatic generation of a fault tree to evaluate the reliability and availability of Wireless Sensor Networks, when permanent faults occur on network devices. The proposal supports any topology, different levels of redundancy, network reconfigurations, criticality of devices and arbitrary failure conditions. The proposed methodology is particularly suitable for the design and validation of Wireless Sensor Networks when trying to optimize its reliability and availability requirements.

Reliability and Availability Evaluation of Wireless Sensor Networks for Industrial Applications

PubMed Central

Silva, Ivanovitch; Guedes, Luiz Affonso; Portugal, Paulo; Vasques, Francisco

2012-01-01

Wireless Sensor Networks (WSN) currently represent the best candidate to be adopted as the communication solution for the last mile connection in process control and monitoring applications in industrial environments. Most of these applications have stringent dependability (reliability and availability) requirements, as a system failure may result in economic losses, put people in danger or lead to environmental damages. Among the different type of faults that can lead to a system failure, permanent faults on network devices have a major impact. They can hamper communications over long periods of time and consequently disturb, or even disable, control algorithms. The lack of a structured approach enabling the evaluation of permanent faults, prevents system designers to optimize decisions that minimize these occurrences. In this work we propose a methodology based on an automatic generation of a fault tree to evaluate the reliability and availability of Wireless Sensor Networks, when permanent faults occur on network devices. The proposal supports any topology, different levels of redundancy, network reconfigurations, criticality of devices and arbitrary failure conditions. The proposed methodology is particularly suitable for the design and validation of Wireless Sensor Networks when trying to optimize its reliability and availability requirements. PMID:22368497

Integrated Magneto-Chemical Sensor For On-Site Food Allergen Detection.

PubMed

Lin, Hsing-Ying; Huang, Chen-Han; Park, Jongmin; Pathania, Divya; Castro, Cesar M; Fasano, Alessio; Weissleder, Ralph; Lee, Hakho

2017-10-24

Adverse food reactions, including food allergies, food sensitivities, and autoimmune reaction (e.g., celiac disease) affect 5-15% of the population and remain a considerable public health problem requiring stringent food avoidance and epinephrine availability for emergency events. Avoiding problematic foods is practically difficult, given current reliance on prepared foods and out-of-home meals. In response, we developed a portable, point-of-use detection technology, termed integrated exogenous antigen testing (iEAT). The system consists of a disposable antigen extraction device coupled with an electronic keychain reader for rapid sensing and communication. We optimized the prototype iEAT system to detect five major food antigens in peanuts, hazelnuts, wheat, milk, and eggs. Antigen extraction and detection with iEAT requires <10 min and achieves high-detection sensitivities (e.g., 0.1 mg/kg for gluten, lower than regulatory limits of 20 mg/kg). When testing under restaurant conditions, we were able to detect hidden food antigens such as gluten within "gluten-free" food items. The small size and rapid, simple testing of the iEAT system should help not only consumers but also other key stakeholders such as clinicians, food industries, and regulators to enhance food safety.

The impact of multiple show-ups on eyewitness decision-making and innocence risk.

PubMed

Smith, Andrew M; Bertrand, Michelle; Lindsay, R C L; Kalmet, Natalie; Grossman, Deborah; Provenzano, Daniel

2014-09-01

If an eyewitness rejects a show-up, police may respond by finding a new suspect and conducting a second show-up with the same eyewitness. Police may continue finding suspects and conducting show-ups until the eyewitness makes an identification (Study 1). Relatively low criterion-setting eyewitnesses filter themselves out of the multiple show-ups procedure by choosing the first suspect with whom they are presented (Studies 2 and 3). Accordingly, response bias was more stringent on the second show-up when compared with the first, but became no more stringent with additional show-ups. Despite this stringent shift in response bias, innocence risk increased with additional show-ups, as false alarms cumulate (Studies 2 and 3). Although unbiased show-up instructions decreased innocent suspect identifications, the numbers were still discouraging (Study 4). Given the high number of innocent suspects who would be mistakenly identified through the use of multiple show-up procedures, using such identifications as evidence of guilt is questionable. Although evidence of guilt is limited to identifications from a single show-up, practical constraints might sometimes require police to use additional show-ups. Accordingly, we propose a stronger partition between evidentiary and investigative procedures. PsycINFO Database Record (c) 2014 APA, all rights reserved.

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.

Tracker controls development and control architecture for the Hobby-Eberly Telescope Wide Field Upgrade

NASA Astrophysics Data System (ADS)

Mock, Jason R.; Beno, Joe; Rafferty, Tom H.; Cornell, Mark E.

2010-07-01

To enable the Hobby-Eberly Telescope Wide Field Upgrade, the University of Texas Center for Electromechanics and McDonald Observatory are developing a precision tracker system - a 15,000 kg robot to position a 3,100 kg payload within 10 microns of a desired dynamic track. Performance requirements to meet science needs and safety requirements that emerged from detailed Failure Modes and Effects Analysis resulted in a system of 14 precision controlled actuators and 100 additional analog and digital devices (primarily sensors and safety limit switches). This level of system complexity and emphasis on fail-safe operation is typical of large modern telescopes and numerous industrial applications. Due to this complexity, demanding accuracy requirements, and stringent safety requirements, a highly versatile and easily configurable centralized control system that easily links with modeling and simulation tools during the hardware and software design process was deemed essential. The Matlab/Simulink simulation environment, coupled with dSPACE controller hardware, was selected for controls development and realization. The dSPACE real-time operating system collects sensor information; motor commands are transmitted over a PROFIBUS network to servo amplifiers and drive motor status is received over the same network. Custom designed position feedback loops, supplemented by feed forward force commands for enhanced performance, and algorithms to accommodate self-locking gearboxes (for safety), reside in dSPACE. To interface the dSPACE controller directly to absolute Heidenhain sensors with EnDat 2.2 protocol, a custom communication board was developed. This paper covers details of software and hardware, design choices and analysis, and supporting simulations (primarily Simulink).

A magnetic isolation and pointing system for the astrometric telescope facility

NASA Technical Reports Server (NTRS)

Smith, Marcie; Hibble, William; Wolke, Patrick J.

1993-01-01

The astrometric telescope facility (ATF), a 20-meter telescope designed for long-term detection and observation of planetary systems outside of the solar system, is scheduled to be a major user of the Space Station's payload pointing system (PPS) capabilities. However, because the ATF has such a stringent pointing stability specification (as low as 0.01 arcsec error over the frequency range from 5 to 200 hertz) and requires +/- 180-degree roll rotation around the telescope's line of sight, the ATF's utilization of the PPS requires the addition of a mechanism or mechanisms to enhance the basic PPS capabilities. The results of a study conducted to investigate the ATF pointing performance achievable by the addition of a magnetic isolation and pointing (MIPS) system between the PPS upper gimbal and the ATF, and separately, by the addition of a passive isolation system between the Space Station and the PPS base are presented. In addition, the study produced requirements on magnetic force and gap motion as a function of the level of Space Station disturbance. These results were used to support the definition of a candidate MIPS. Pointing performance results from the study indicate that a MIPS can meet the ATF pointing requirements in the presence of a PPS base transitional acceleration of up to 0.018g, with reasonable restrictions placed on the isolation and pointing bandwidths. By contrast, the passive base isolator system must have an unrealistically low isolation bandwidth on all axes (less than 0.1 hertz) to meet ATF pointing requirements. The candidate MIPS is based on an assumed base translational disturbance of 0.01g. The system fits within the available annular region between the PPS and ATF while meeting power and weight limitations and providing the required payload roll motion. Payload data and power services are provided by noncontacting transfer devices.

A production-theory-based framework for analysing recycling systems in the e-waste sector

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

Schmidt, Mario

2005-07-15

Modern approaches in the production theory of business and management economics propose that objects (e.g. materials) be divided into good, bad or neutral. In transformation processes such as occur in production or recycling this makes it possible to distinguish stringently between the economic revenue of a process and the economic and ecological expenditures for it. This approach can be transferred to entire systems of processes in order to determine the system revenue and the system expenditure. Material flow nets or graphs are used for this purpose. In complex material flow systems it becomes possible to calculate not only the costs,more » but also the direct and indirect environmental impacts of an individual process or a system revenue (for example a product or the elimination of waste) consistently. The approach permits a stringent analysis as well as different analysis perspectives of a material flow system. It is particularly suitable for closed-loop economic systems in which material backflows occur. With the aid of an example developed jointly with Hewlett Packard Europe, the paper outlines how this approach can be employed in the field of e-waste management.« less

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

Adams, D.; Alekou, A.; Apollonio, M.

Here, the international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240\\,MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less thanmore » $$\\sim$$1% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is $$f_\\pi < 1.4\\%$$ at 90% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling.« less

Current Scenario of Spurious and Substandard Medicines in India: A Systematic Review

PubMed Central

Khan, A. N.; Khar, R. K.

2015-01-01

Globally, every country is the victim of substandard or spurious drugs, which result in life threatening issues, financial loss of consumer and manufacturer and loss in trust on health system. The aim of this enumerative review was to probe the extent on poor quality drugs with their consequences on public health and the preventive measures taken by the Indian pharmaceutical regulatory system. Government and non-government studies, literature and news were gathered from journals and authentic websites. All data from 2000 to 2013 were compiled and interpreted to reveal the real story of poor quality drugs in India. For minimizing spurious/falsely-labelled/falsified/counterfeit drugs or not of standard quality drugs, there is urgent requirement of more stringent regulation and legal action against the problem. However, India has taken some preventive steps in the country to fight against the poor quality drugs for protecting and promoting the public health. PMID:25767312

Characterization of individual mouse cerebrospinal fluid proteomes

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

Smith, Jeffrey S.; Angel, Thomas E.; Chavkin, Charles

2014-03-20

Analysis of cerebrospinal fluid (CSF) offers key insight into the status of the central nervous system. Characterization of murine CSF proteomes can provide a valuable resource for studying central nervous system injury and disease in animal models. However, the small volume of CSF in mice has thus far limited individual mouse proteome characterization. Through non-terminal CSF extractions in C57Bl/6 mice and high-resolution liquid chromatography-mass spectrometry analysis of individual murine samples, we report the most comprehensive proteome characterization of individual murine CSF to date. Utilizing stringent protein inclusion criteria that required the identification of at least two unique peptides (1% falsemore » discovery rate at the peptide level) we identified a total of 566 unique proteins, including 128 proteins from three individual CSF samples that have been previously identified in brain tissue. Our methods and analysis provide a mechanism for individual murine CSF proteome analysis.« less

A 0.18 μm CMOS LDO Regulator for an On-Chip Sensor Array Impedance Measurement System.

PubMed

Pérez-Bailón, Jorge; Márquez, Alejandro; Calvo, Belén; Medrano, Nicolás

2018-05-02

This paper presents a fully integrated 0.18 μm CMOS Low-Dropout (LDO) Voltage Regulator specifically designed to meet the stringent requirements of a battery-operated impedance spectrometry multichannel CMOS micro-instrument. The proposed LDO provides a regulated 1.8 V voltage from a 3.6 V to 1.94 V battery voltage over a −40 °C to 100 °C temperature range, with a compact topology (<0.10 mm² area) and a constant quiescent current of only 7.45 μA with 99.985% current efficiency, achieving remarkable state-of-art Figures of Merit (FoMs) for the regulating⁻transient performance. Experimental measurements validate its suitability for the target application, paving the way towards the future achievement of a truly portable System on Chip (SoC) platform for impedance sensors.

Power system design of ESMO

NASA Astrophysics Data System (ADS)

Ulrich, Steve; Veilleux, Jean-François; Landry Corbin, François

2009-01-01

The European Student Moon Orbiter (ESMO) spacecraft is a student-built mini satellite being designed for a mission to the Moon. Designing and launching mini satellites are becoming a current trend in the space sector since they provide an economic way to perform innovative scientific experiments and in-flight demonstration of novel space technologies. The generation, storage, control, and distribution of the electrical power in a mini satellite represents unique challenges to the power engineer since the mass and volume restrictions are very stringent. Regardless of these problems, every subsystem and payload equipment must be operated within their specified voltage band whenever they required to be turned on. This paper presents the preliminary design of a lightweight, compact, and reliable power system for ESMO that can generate 720 W. Some of the key components of the EPS include ultra triple-junction (UTJ) GaAs solar cells controlled by maximum power point trackers, and high efficiency Li-ion secondary batteries recharged in parallel.

Pion contamination in the MICE muon beam

NASA Astrophysics Data System (ADS)

Adams, D.; Alekou, A.; Apollonio, M.; Asfandiyarov, R.; Barber, G.; Barclay, P.; de Bari, A.; Bayes, R.; Bayliss, V.; Bertoni, R.; Blackmore, V. J.; Blondel, A.; Blot, S.; Bogomilov, M.; Bonesini, M.; Booth, C. N.; Bowring, D.; Boyd, S.; Brashaw, T. W.; Bravar, U.; Bross, A. D.; Capponi, M.; Carlisle, T.; Cecchet, G.; Charnley, C.; Chignoli, F.; Cline, D.; Cobb, J. H.; Colling, G.; Collomb, N.; Coney, L.; Cooke, P.; Courthold, M.; Cremaldi, L. M.; DeMello, A.; Dick, A.; Dobbs, A.; Dornan, P.; Drews, M.; Drielsma, F.; Filthaut, F.; Fitzpatrick, T.; Franchini, P.; Francis, V.; Fry, L.; Gallagher, A.; Gamet, R.; Gardener, R.; Gourlay, S.; Grant, A.; Greis, J. R.; Griffiths, S.; Hanlet, P.; Hansen, O. M.; Hanson, G. G.; Hart, T. L.; Hartnett, T.; Hayler, T.; Heidt, C.; Hills, M.; Hodgson, P.; Hunt, C.; Iaciofano, A.; Ishimoto, S.; Kafka, G.; Kaplan, D. M.; Karadzhov, Y.; Kim, Y. K.; Kuno, Y.; Kyberd, P.; Lagrange, J.-B.; Langlands, J.; Lau, W.; Leonova, M.; Li, D.; Lintern, A.; Littlefield, M.; Long, K.; Luo, T.; Macwaters, C.; Martlew, B.; Martyniak, J.; Mazza, R.; Middleton, S.; Moretti, A.; Moss, A.; Muir, A.; Mullacrane, I.; Nebrensky, J. J.; Neuffer, D.; Nichols, A.; Nicholson, R.; Nugent, J. C.; Oates, A.; Onel, Y.; Orestano, D.; Overton, E.; Owens, P.; Palladino, V.; Pasternak, J.; Pastore, F.; Pidcott, C.; Popovic, M.; Preece, R.; Prestemon, S.; Rajaram, D.; Ramberger, S.; Rayner, M. A.; Ricciardi, S.; Roberts, T. J.; Robinson, M.; Rogers, C.; Ronald, K.; Rubinov, P.; Rucinski, P.; Sakamato, H.; Sanders, D. A.; Santos, E.; Savidge, T.; Smith, P. J.; Snopok, P.; Soler, F. J. P.; Speirs, D.; Stanley, T.; Stokes, G.; Summers, D. J.; Tarrant, J.; Taylor, I.; Tortora, L.; Torun, Y.; Tsenov, R.; Tunnell, C. D.; Uchida, M. A.; Vankova-Kirilova, G.; Virostek, S.; Vretenar, M.; Warburton, P.; Watson, S.; White, C.; Whyte, C. G.; Wilson, A.; Winter, M.; Yang, X.; Young, A.; Zisman, M.

2016-03-01

The international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240 MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less than ~1% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is fπ < 1.4% at 90% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling.

Pion contamination in the MICE muon beam

DOE PAGES

Adams, D.; Alekou, A.; Apollonio, M.; ...

2016-03-01

Here, the international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240\\,MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less thanmore » $$\\sim$$1% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is $$f_\\pi < 1.4\\%$$ at 90% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling.« less

The evolution of CELSS for lunar bases. [Controlled Ecological Life Support Systems

NASA Technical Reports Server (NTRS)

Macelroy, R. D.; Klein, H. P.; Averner, M. M.

1985-01-01

A bioregenerative life support system designed to address the fundamental requirements of a functioning independent lunar base is presented in full. Issues to be discussed are associated with CELSS weight, volume and cost of operation. The fundamental CELSS component is a small, highly automated module containing plants which photosynthesize and provide the crew with food, water and oxygen. Hydrogen, nitrogen and carbon dioxide will be initially brought in from earth, recycled and their waste products conserved. As the insufficiency of buffers necessitates stringent cybernetic control, a stable state will be maintained by computer control. Through genetic engineering and carbon dioxide, temperature, and nutrient manipulation, plant productivity can be increased, while the area necessary for growth and illumination energy decreased. In addition, photosynthetic efficiency can be enhanced through lamp design, fiber optics and the use of appropriate wavelengths. Crop maintenance will be performed by robotics, as a means of preventing plant ailments.

Ultralow-power electronics for biomedical applications.

PubMed

Chandrakasan, Anantha P; Verma, Naveen; Daly, Denis C

2008-01-01

The electronics of a general biomedical device consist of energy delivery, analog-to-digital conversion, signal processing, and communication subsystems. Each of these blocks must be designed for minimum energy consumption. Specific design techniques, such as aggressive voltage scaling, dynamic power-performance management, and energy-efficient signaling, must be employed to adhere to the stringent energy constraint. The constraint itself is set by the energy source, so energy harvesting holds tremendous promise toward enabling sophisticated systems without straining user lifestyle. Further, once harvested, efficient delivery of the low-energy levels, as well as robust operation in the aggressive low-power modes, requires careful understanding and treatment of the specific design limitations that dominate this realm. We outline the performance and power constraints of biomedical devices, and present circuit techniques to achieve complete systems operating down to power levels of microwatts. In all cases, approaches that leverage advanced technology trends are emphasized.

Polarization Effects Aboard the Space Interferometry Mission

NASA Technical Reports Server (NTRS)

Levin, Jason; Young, Martin; Dubovitsky, Serge; Dorsky, Leonard

2006-01-01

For precision displacement measurements, laser metrology is currently one of the most accurate measurements. Often, the measurement is located some distance away from the laser source, and as a result, stringent requirements are placed on the laser delivery system with respect to the state of polarization. Such is the case with the fiber distribution assembly (FDA) that is slated to fly aboard the Space Interferometry Mission (SIM) next decade. This system utilizes a concatenated array of couplers, polarizers and lengthy runs of polarization-maintaining (PM) fiber to distribute linearly-polarized light from a single laser to fourteen different optical metrology measurement points throughout the spacecraft. Optical power fluctuations at the point of measurement can be traced back to the polarization extinction ration (PER) of the concatenated components, in conjunction with the rate of change in phase difference of the light along the slow and fast axes of the PM fiber.

An Open-Source Hardware and Software System for Acquisition and Real-Time Processing of Electrophysiology during High Field MRI

PubMed Central

Purdon, Patrick L.; Millan, Hernan; Fuller, Peter L.; Bonmassar, Giorgio

2008-01-01

Simultaneous recording of electrophysiology and functional magnetic resonance imaging (fMRI) is a technique of growing importance in neuroscience. Rapidly evolving clinical and scientific requirements have created a need for hardware and software that can be customized for specific applications. Hardware may require customization to enable a variety of recording types (e.g., electroencephalogram, local field potentials, or multi-unit activity) while meeting the stringent and costly requirements of MRI safety and compatibility. Real-time signal processing tools are an enabling technology for studies of learning, attention, sleep, epilepsy, neurofeedback, and neuropharmacology, yet real-time signal processing tools are difficult to develop. We describe an open source system for simultaneous electrophysiology and fMRI featuring low-noise (< 0.6 uV p-p input noise), electromagnetic compatibility for MRI (tested up to 7 Tesla), and user-programmable real-time signal processing. The hardware distribution provides the complete specifications required to build an MRI-compatible electrophysiological data acquisition system, including circuit schematics, print circuit board (PCB) layouts, Gerber files for PCB fabrication and robotic assembly, a bill of materials with part numbers, data sheets, and vendor information, and test procedures. The software facilitates rapid implementation of real-time signal processing algorithms. This system has used in human EEG/fMRI studies at 3 and 7 Tesla examining the auditory system, visual system, sleep physiology, and anesthesia, as well as in intracranial electrophysiological studies of the non-human primate visual system during 3 Tesla fMRI, and in human hyperbaric physiology studies at depths of up to 300 feet below sea level. PMID:18761038

An open-source hardware and software system for acquisition and real-time processing of electrophysiology during high field MRI.

PubMed

Purdon, Patrick L; Millan, Hernan; Fuller, Peter L; Bonmassar, Giorgio

2008-11-15

Simultaneous recording of electrophysiology and functional magnetic resonance imaging (fMRI) is a technique of growing importance in neuroscience. Rapidly evolving clinical and scientific requirements have created a need for hardware and software that can be customized for specific applications. Hardware may require customization to enable a variety of recording types (e.g., electroencephalogram, local field potentials, or multi-unit activity) while meeting the stringent and costly requirements of MRI safety and compatibility. Real-time signal processing tools are an enabling technology for studies of learning, attention, sleep, epilepsy, neurofeedback, and neuropharmacology, yet real-time signal processing tools are difficult to develop. We describe an open-source system for simultaneous electrophysiology and fMRI featuring low-noise (<0.6microV p-p input noise), electromagnetic compatibility for MRI (tested up to 7T), and user-programmable real-time signal processing. The hardware distribution provides the complete specifications required to build an MRI-compatible electrophysiological data acquisition system, including circuit schematics, print circuit board (PCB) layouts, Gerber files for PCB fabrication and robotic assembly, a bill of materials with part numbers, data sheets, and vendor information, and test procedures. The software facilitates rapid implementation of real-time signal processing algorithms. This system has been used in human EEG/fMRI studies at 3 and 7T examining the auditory system, visual system, sleep physiology, and anesthesia, as well as in intracranial electrophysiological studies of the non-human primate visual system during 3T fMRI, and in human hyperbaric physiology studies at depths of up to 300 feet below sea level.

Atomic precision etch using a low-electron temperature plasma

NASA Astrophysics Data System (ADS)

Dorf, L.; Wang, J.-C.; Rauf, S.; Zhang, Y.; Agarwal, A.; Kenney, J.; Ramaswamy, K.; Collins, K.

2016-03-01

Sub-nm precision is increasingly being required of many critical plasma etching processes in the semiconductor industry. Accurate control over ion energy and ion/radical composition is needed during plasma processing to meet these stringent requirements. Described in this work is a new plasma etch system which has been designed with the requirements of atomic precision plasma processing in mind. In this system, an electron sheet beam parallel to the substrate surface produces a plasma with an order of magnitude lower electron temperature Te (~ 0.3 eV) and ion energy Ei (< 3 eV without applied bias) compared to conventional radio-frequency (RF) plasma technologies. Electron beam plasmas are characterized by higher ion-to-radical fraction compared to RF plasmas, so a separate radical source is used to provide accurate control over relative ion and radical concentrations. Another important element in this plasma system is low frequency RF bias capability which allows control of ion energy in the 2-50 eV range. Presented in this work are the results of etching of a variety of materials and structures performed in this system. In addition to high selectivity and low controllable etch rate, an important requirement of atomic precision etch processes is no (or minimal) damage to the remaining material surface. It has traditionally not been possible to avoid damage in RF plasma processing systems, even during atomic layer etch. The experiments for Si etch in Cl2 based plasmas in the aforementioned etch system show that damage can be minimized if the ion energy is kept below 10 eV. Layer-by-layer etch of Si is also demonstrated in this etch system using electrical and gas pulsing.

76 FR 46842 - Notice of Lodging of Consent Decree Under the Clean Air Act

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-03

..., Section 301(a) of the Clean Water Act, 42 U.S.C. 1311(a), and Section 3005(a) of the Resource Conservation..., Michigan. Under the Consent Decree, Dow will implement an Enhanced Leak Detection and Repair (``LDAR'') Program which imposes leak monitoring and repair requirements more stringent than existing LDAR...

Diving into Data: Developing the Capacity for Data Literacy in Teacher Education

ERIC Educational Resources Information Center

Dunlap, Karen; Piro, Jody S.

2016-01-01

Educators by definition are now required to utilize a variety of student data to shape the decisions they make and design the lessons they teach. As accountability standards become more stringent and as teachers face increasingly diverse student populations within their classrooms, they often struggle to adequately meet the needs of all learners.…

78 FR 8361 - Flightcrew Member Duty and Rest Requirements; Technical Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-06

...). Because these short-call-reserve limits were not intended to be more stringent than flight-duty-period... short-call reserve to have the same extension as a flight duty period. Accordingly, in the final rule... [Docket No. FAA-2009-1093; Amdt. Nos. 117-1, 119-16, 121-357] RIN 2120-AJ58 Flightcrew Member Duty and...

Engineering Design Handbook. Breech Mechanism Design

DTIC Science & Technology

1979-02-01

4-22 4-11.2 Tool and Gage Requirements ...................................... 4-22 R eferences...16 4-5 Total Cost per Piece---Sum of Tool Costs, Machining Cost, and Nonproductive Cost ....................................................... 4-20 4...practical design limits are end of the gun tube from which the projectile numerous as well as stringent Today, the multi- emerges and the breecb end is that

Limiting Central Government Budget Deficits: International Experiences

DTIC Science & Technology

2010-03-11

Economic Cooperation and Development ( OECD ) countries, limit their fiscal deficits. Financial markets support government efforts to reduce deficit...fiscal consolidation efforts and developing medium-term budgetary frameworks for fiscal planning . Fiscal consolidation efforts, however, generally...require policymakers to weigh the effects of various policy trade-offs, including the trade-off between adopting stringent, but enforceable, rules- based

Practical experience with full-scale structured sheet media (SSM) integrated fixed-film activated sludge (IFAS) systems for nitrification.

PubMed

Li, Hua; Zhu, Jia; Flamming, James J; O'Connell, Jack; Shrader, Michael

2015-01-01

Many wastewater treatment plants in the USA, which were originally designed as secondary treatment systems with no or partial nitrification requirements, are facing increased flows, loads, and more stringent ammonia discharge limits. Plant expansion is often not cost-effective due to either high construction costs or lack of land. Under these circumstances, integrated fixed-film activated sludge (IFAS) systems using both suspended growth and biofilms that grow attached to a fixed plastic structured sheet media are found to be a viable solution for solving the challenges. Multiple plants have been retrofitted with such IFAS systems in the past few years. The system has proven to be efficient and reliable in achieving not only consistent nitrification, but also enhanced bio-chemical oxygen demand removal and sludge settling characteristics. This paper presents long-term practical experiences with the IFAS system design, operation and maintenance, and performance for three full-scale plants with distinct processes; that is, a trickling filter/solids contact process, a conventional plug flow activated sludge process and an extended aeration process.

Transient Thermal Analyses of Passive Systems on SCEPTOR X-57

NASA Technical Reports Server (NTRS)

Chin, Jeffrey C.; Schnulo, Sydney L.; Smith, Andrew D.

2017-01-01

As efficiency, emissions, and noise become increasingly prominent considerations in aircraft design, turning to an electric propulsion system is a desirable solution. Achieving the intended benefits of distributed electric propulsion (DEP) requires thermally demanding high power systems, presenting a different set of challenges compared to traditional aircraft propulsion. The embedded nature of these heat sources often preclude the use of traditional thermal management systems in order to maximize performance, with less opportunity to exhaust waste heat to the surrounding environment. This paper summarizes the thermal analyses of X-57 vehicle subsystems that don't employ externally air-cooled heat sinks. The high-power battery, wires, high-lift motors, and aircraft outer surface are subjected to heat loads with stringent thermal constraints. The temperature of these components are tracked transiently, since they never reach a steady-state equilibrium. Through analysis and testing, this report demonstrates that properly characterizing the material properties is key to accurately modeling peak temperature of these systems, with less concern for spatial thermal gradients. Experimentally validated results show the thermal profile of these systems can be sufficiently estimated using reduced order approximations.

High Power mm-Wave Transmitter System for Radar or Telecommunications

NASA Technical Reports Server (NTRS)

Stride, S. L.; McMaster, R. L.; Pogorzelski, R. J.

2003-01-01

Future NASA deep space missions able to provide tens of kilo-watts of spacecraft DC power, make it feasible to employ high power RF telecommunications systems. Traditional flight systems (e.g., Cassini), constrained by limited DC power, used a single high-gain 4m Cassegrain reflector fed by a single lower power (20W) transmitter. Increased available DC power means that high power (1000 W) transmitters can be used. Rather than continue building traditional single-transmitter systems it now becomes feasible to engineer and build multi-element active arrays that can illuminate a dish. Illuminating a 2m dish with a spherical wavefront from an offset 1kW active array can provide sufficient ERP (Effective Radiated Power) when compared to a larger Cassegrain dish. Such a system has the advantage of lower mass, lower volume, improved reliability, less stringent pointing requirements, lower cost and risk. We propose to design and build a prototype Ka-band transmit antenna with an active sub-array using 125W TWTAs. The system could be applied to a telecommunications downlink or radar transmitter used for missions such as JIMO.

SS/RCS surface tension propellant acquisition/expulsion tankage technology

NASA Technical Reports Server (NTRS)

1975-01-01

The analysis, design, fabrication, and testing of a propellant tank that satisfies the requirements of the space shuttle is presented. This mission presents very stringent and sometimes conflicting requirements. A compartmented-tank device was developed and various ground and drop tower test techniques were employed to verify the design using both subscale and full-scale hardware. Performance was established with scale models and further substantiation was obtained with the full-scale tankage. Fabrication, acceptance, fill and drain, inspection, and other ground handling procedures were developed.

End User Acceptance - Requirements or Specifications, Certification, Testing

NASA Technical Reports Server (NTRS)

Jeevarajan, Judith

2013-01-01

NASA follows top level safety requirement of two-failure tolerance (t hree levels of controls or design for minimum risk) to all catastroph ic hazards in the design of safe li-ion batteries for space use. ? R igorous development testing at appropriate levels to credible offnominal conditions and review of test data. ? Implement robust design con trols based on test results and test again to confirm safety at the a ppropriate levels. ? Stringent testing of all (100%) flight batteries (from button cells to large batteries).

17-4 PH and 15-5 PH

NASA Technical Reports Server (NTRS)

Johnson, Howard T.

1995-01-01

17-4 PH and 15-5 PH are extremely useful and versatile precipitation-hardening stainless steels. Armco 17-4 PH is well suited for the magnetic particle inspection requirements of Aerospace Material Specification. Armco 15-5 PH and 17-4 PH are produced in billet, plate, bar, and wire. Also, 15-5 PH is able to meet the stringent mechanical properties required in the aerospace and nuclear industries. Both products are easy to heat treat and machine, making them very useful in many applications.

High Performance, Robust Control of Flexible Space Structures: MSFC Center Director's Discretionary Fund

NASA Technical Reports Server (NTRS)

Whorton, M. S.

1998-01-01

Many spacecraft systems have ambitious objectives that place stringent requirements on control systems. Achievable performance is often limited because of difficulty of obtaining accurate models for flexible space structures. To achieve sufficiently high performance to accomplish mission objectives may require the ability to refine the control design model based on closed-loop test data and tune the controller based on the refined model. A control system design procedure is developed based on mixed H2/H(infinity) optimization to synthesize a set of controllers explicitly trading between nominal performance and robust stability. A homotopy algorithm is presented which generates a trajectory of gains that may be implemented to determine maximum achievable performance for a given model error bound. Examples show that a better balance between robustness and performance is obtained using the mixed H2/H(infinity) design method than either H2 or mu-synthesis control design. A second contribution is a new procedure for closed-loop system identification which refines parameters of a control design model in a canonical realization. Examples demonstrate convergence of the parameter estimation and improved performance realized by using the refined model for controller redesign. These developments result in an effective mechanism for achieving high-performance control of flexible space structures.

Specialized data analysis for the Space Shuttle Main Engine and diagnostic evaluation of advanced propulsion system components

NASA Technical Reports Server (NTRS)

1993-01-01

The Marshall Space Flight Center is responsible for the development and management of advanced launch vehicle propulsion systems, including the Space Shuttle Main Engine (SSME), which is presently operational, and the Space Transportation Main Engine (STME) under development. The SSME's provide high performance within stringent constraints on size, weight, and reliability. Based on operational experience, continuous design improvement is in progress to enhance system durability and reliability. Specialized data analysis and interpretation is required in support of SSME and advanced propulsion system diagnostic evaluations. Comprehensive evaluation of the dynamic measurements obtained from test and flight operations is necessary to provide timely assessment of the vibrational characteristics indicating the operational status of turbomachinery and other critical engine components. Efficient performance of this effort is critical due to the significant impact of dynamic evaluation results on ground test and launch schedules, and requires direct familiarity with SSME and derivative systems, test data acquisition, and diagnostic software. Detailed analysis and evaluation of dynamic measurements obtained during SSME and advanced system ground test and flight operations was performed including analytical/statistical assessment of component dynamic behavior, and the development and implementation of analytical/statistical models to efficiently define nominal component dynamic characteristics, detect anomalous behavior, and assess machinery operational condition. In addition, the SSME and J-2 data will be applied to develop vibroacoustic environments for advanced propulsion system components, as required. This study will provide timely assessment of engine component operational status, identify probable causes of malfunction, and indicate feasible engineering solutions. This contract will be performed through accomplishment of negotiated task orders.

77 FR 36274 - Public Water System Supervision Program Revision for the State of Alabama

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-18

... Surface Water Treatment Rule, Long Term 2 Enhanced Surface Water Treatment Rule, and Stage 2 Disinfection/Disinfection Byproducts Rule. EPA has determined that Alabama's rules are no less stringent than the...

Application of IUS equipment and experience to orbit transfer vehicles of the 90's

NASA Astrophysics Data System (ADS)

Bangsund, E.; Keeney, J.; Cowgill, E.

1985-10-01

This paper relates experiences with the IUS program and the application of that experience to Future Orbit Transfer Vehicles. More specifically it includes the implementation of the U.S. Air Force Space Division high reliability parts standard (SMASO STD 73-2C) and the component/system test standard (MIL-STD-1540A). Test results from the parts and component level testing and the resulting system level test program for fourteen IUS flight vehicles are discussed. The IUS program has had the highest compliance with these standards and thus offers a benchmark of experience for future programs demanding extreme reliability. In summary, application of the stringent parts standard has resulted in fewer failures during testing and the stringent test standard has eliminated design problems in the hardware. Both have been expensive in costs and schedules, and should be applied with flexibility.

A front-end electronic system for large arrays of bolometers

NASA Astrophysics Data System (ADS)

Arnaboldi, C.; Carniti, P.; Cassina, L.; Gotti, C.; Liu, X.; Maino, M.; Pessina, G.; Rosenfeld, C.; Zhu, B. X.

2018-02-01

CUORE is an array of thermal calorimeters composed of 988 crystals held at about 10 mK, whose absorbed energy is read out with semiconductor thermistors. The composition of the crystal is TeO2, and the aim is the study of the double beta decay of 130Te on very long and stable runs. CUPID-0 is an array of 26 Zn82Se crystals with double thermistor readout to study the double beta decay of 82Se. In the present paper, we present an overview of the entire front-end electronic readout chain, from the preamplifier to the anti-aliasing filter. This overview includes motivations, design strategies, circuit implementation and performance results of the electronic system, including other auxiliary yet important elements like power supplies and the slow control communication system. The stringent requirements of stability on the very long experimental runs that are foreseen during CUORE and CUPID-0 operation, are achieved thanks to novel solutions of the front-end preamplifier and of the detector bias circuit setup.

MICROSCOPE mission: drag-free and attitude control system expertise activities toward the scientific team

NASA Astrophysics Data System (ADS)

Delavault, Stéphanie; Prieur, Pascal; Liénart, Thomas; Robert, Alain; Guidotti, Pierre-Yves

2018-04-01

Microscope is a CNES-ESA-ONERA-CNRS-OCA-DLR-ZARM mission dedicated to the test of the Equivalence Principle with an improved accuracy of 10-15. The 300 kg drag-free microsatellite was launched on April 25th 2016 into a 710 km dawndusk sun-synchronous orbit for a 2-year mission. To comply with stringent requirements, the drag-free and attitude control system (DFACS) involves the scientific accelerometer as main sensor and a set of 8 cold gas proportional thrusters. Once in mission mode, within the CNES drag-free expertise center (CECT) the DFACS team provides several services to the system and to the scientific mission center: cold gas monitoring and management, `Attitude' ancillary data, DFACS expertise ancillary data. For this purpose, expertise tools have been implemented in the CECT, using the flexibility and efficiency of Matlab™ utilities. This paper presents the role of the CECT within the mission and details the expertise activities of the DFACS team illustrated with some typical in flight results.

Relative phase noise induced impairment in M-ary phase-shift-keying coherent optical communication system using distributed fiber Raman amplifier.

PubMed

Cheng, Jingchi; Tang, Ming; Fu, Songnian; Shum, Perry Ping; Liu, Deming

2013-04-01

We show for the first time, to the best of our knowledge, that, in a coherent communication system that employs a phase-shift-keying signal and Raman amplification, besides the pump relative intensity noise (RIN) transfer to the amplitude, the signal's phase will also be affected by pump RIN through the pump-signal cross-phase modulation. Although the average pump power induced linear phase change can be compensated for by the phase-correction algorithm, a relative phase noise (RPN) parameter has been found to characterize pump RIN induced stochastic phase noise. This extra phase noise brings non-negligible system impairments in terms of the Q-factor penalty. The calculation shows that copumping leads to much more stringent requirements to pump RIN, and relatively larger fiber dispersion helps to suppress the RPN induced impairment. A higher-order phase-shift keying (PSK) signal is less tolerant to noise than a lower-order PSK.

Open-systems architecture of a standardized command interface chip-set for switching and control of a spacecraft power bus

NASA Technical Reports Server (NTRS)

Ruiz, Ian B.; Burke, Gary R.; Lung, Gerald; Whitaker, William D.; Nowicki, Robert M.

2004-01-01

The Jet Propulsion Laboratory (JPL) has developed a command interface chip-set that primarily consists of two mixed-signal ASICs'; the Command Interface ASIC (CIA) and Analog Interface ASIC (AIA). The Open-systems architecture employed during the design of this chip-set enables its use as both an intelligent gateway between the system's flight computer and the control, actuation, and activation of the spacecraft's loads, valves, and pyrotechnics respectfully as well as the regulator of the spacecraft power bus. Furthermore, the architecture is highly adaptable and employed fault-tolerant design methods enabling a host of other mission uses including reliable remote data collection. The objective of this design is to both provide a needed flight component that meets the stringent environmental requirements of current deep space missions and to add a new element to a growing library that can be used as a standard building block for future missions to the outer planets.

Energy and water quality management systems for water utility's operations: a review.

PubMed

Cherchi, Carla; Badruzzaman, Mohammad; Oppenheimer, Joan; Bros, Christopher M; Jacangelo, Joseph G

2015-04-15

Holistic management of water and energy resources is critical for water utilities facing increasing energy prices, water supply shortage and stringent regulatory requirements. In the early 1990s, the concept of an integrated Energy and Water Quality Management System (EWQMS) was developed as an operational optimization framework for solving water quality, water supply and energy management problems simultaneously. Approximately twenty water utilities have implemented an EWQMS by interfacing commercial or in-house software optimization programs with existing control systems. For utilities with an installed EWQMS, operating cost savings of 8-15% have been reported due to higher use of cheaper tariff periods and better operating efficiencies, resulting in the reduction in energy consumption of ∼6-9%. This review provides the current state-of-knowledge on EWQMS typical structural features and operational strategies and benefits and drawbacks are analyzed. The review also highlights the challenges encountered during installation and implementation of EWQMS and identifies the knowledge gaps that should motivate new research efforts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Precision experiments on mirror transitions at Notre Dame

NASA Astrophysics Data System (ADS)

Brodeur, Maxime; TwinSol Collaboration

2016-09-01

Thanks to extensive experimental efforts that led to a precise determination of important experimental quantities of superallowed pure Fermi transitions, we now have a very precise value for Vud that leads to a stringent test of the CKM matrix unitarity. Despite this achievement, measurements in other systems remain relevant as conflicting results could uncover unknown systematic effects or even new physics. One such system is the superallowed mixed transition, which can help refine theoretical corrections used for pure Fermi transitions and improve the accuracy of Vud. However, as a corrected Ft-value determination from these systems requires the more challenging determination of the Fermi Gamow-Teller mixing ratio, only five transitions, spreading from 19Ne to 37Ar, are currently fully characterized. To rectify the situation, an experimental program on precision experiment of mirror transitions that includes precision half-life measurements, and in the future, the determination of the Fermi Gamow-Teller mixing ratio, has started at the University of Notre Dame. This work is supported in part by the National Science Foundation.

NIST torsion oscillator viscometer response: Performance on the LeRC active vibration isolation platform

NASA Technical Reports Server (NTRS)

Berg, Robert F.; Grodsinsky, Carlos M.

1992-01-01

Critical point viscosity measurements are limited to their reduced temperature approach to T(sub c) in an Earth bound system, because of density gradients imposed by gravity. Therefore, these classes of experiments have been proposed as good candidates for 'microgravity' science experiments where this limitation is not present. The nature of these viscosity measurements dictate hardware that is sensitive to low frequency excitations. Because of the vibratory acceleration sensitivity of a torsion oscillator viscometer, used to acquire such measurements, a vibration isolation sensitivity test was performed on candidate 'microgravity' hardware to study the possibility of meeting the stringent oscillatory sensitivity requirements of a National Institute of Standards and Technology (NIST) torsion oscillator viscometer. A prototype six degree of freedom active magnetic isolation system, developed at NASA Lewis Research Center, was used as the isolation system. The ambient acceleration levels of the platform were reduced to the noise floor levels of its control sensors, about one microgravity in the 0.1 to 10 Hz bandwidth.

Do we need a special ethics for research?

PubMed

Hansson, Sven Ove

2011-03-01

Research is subject to more stringent ethical requirements than most other human activities, and a procedure that is otherwise allowed may be forbidden in research. Hence, risk-taking is more restricted in scientific research than in most non-research contexts, and privacy is better protected in scientific questionnaires than in marketing surveys. Potential arguments for this difference are scrutinized. The case in its favour appears to be weak. A stronger case can be made in favour of a difference in the opposite direction: If perilous or otherwise problematic activities have to be performed it is usually better to perform them in a research context where they are properly evaluated so that guidance is obtained for the future. However, retreating from current ethical demands on research is not a desirable direction to go. Instead, research ethics can serve to inspire the introduction of more stringent ethical principles in other social sectors.

Nitrogen stress response and stringent response are coupled in Escherichia coli

PubMed Central

Brown, Daniel R.; Barton, Geraint; Pan, Zhensheng; Buck, Martin; Wigneshweraraj, Sivaramesh

2014-01-01

Assimilation of nitrogen is an essential process in bacteria. The nitrogen regulation stress response is an adaptive mechanism used by nitrogen-starved Escherichia coli to scavenge for alternative nitrogen sources and requires the global transcriptional regulator NtrC. In addition, nitrogen-starved E. coli cells synthesize a signal molecule, guanosine tetraphosphate (ppGpp), which serves as an effector molecule of many processes including transcription to initiate global physiological changes, collectively termed the stringent response. The regulatory mechanisms leading to elevated ppGpp levels during nutritional stresses remain elusive. Here, we show that transcription of relA, a key gene responsible for the synthesis of ppGpp, is activated by NtrC during nitrogen starvation. The results reveal that NtrC couples these two major bacterial stress responses to manage conditions of nitrogen limitation, and provide novel mechanistic insights into how a specific nutritional stress leads to elevating ppGpp levels in bacteria. PMID:24947454

Gauge field localization on brane worlds

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

Guerrero, Rommel; Rodriguez, R. Omar; Melfo, Alejandra

2010-04-15

We consider the effects of spacetime curvature and brane thickness on the localization of gauge fields on a brane via kinetic terms induced by localized fermions. We find that in a warped geometry with an infinitely thin brane, both the infrared and the ultraviolet behavior of the electromagnetic propagator are affected, providing a more stringent bound on the brane's tension than that coming from the requirement of four-dimensional gravity on the brane. On the other hand, for a thick wall in a flat spacetime, where the fermions are localized by means of a Yukawa coupling, we find that four-dimensional electromagnetismmore » is recovered in a region bounded from above by the same critical distance appearing in the thin case, but also from below by a new scale related to the brane's thickness and the electromagnetic couplings. This imposes very stringent bounds on the brane's thickness which seem to invalidate the localization mechanism for this case.« less

Solar Heating And Cooling Of Buildings (SHACOB): Requirements definition and impact analysis-2. Volume 1: Energy-conserving design for residential structures

NASA Astrophysics Data System (ADS)

Cretcher, C. K.

1980-11-01

The impact of stringent energy conserving building standards on electric utility service areas and their customers was analyzed. The demands on the seven broadly representative electric utilities were aggregated to represent the total new construction electric heating demands in the years 1990 and 2000 to be compared to the aggregate obtained similarly for a nominal, less stringent standard, viz., ASHRAE 90-75. Results presented include the percentage of energy savings achieved in both heating and cooling seasons and typical demand profile changes. A utility economic impact analysis was performed for the cases investigated to determine changes in operating costs and potential capacity sales. A third cost component considered is the incremental cost of superinsulation (over ASHRAE 90-75) to the customer. The aggregate net cost to the utility/customer entity is utilized as a measure of overall economic benefit.

Characterization of spacecraft and environmental disturbances on a SmallSat

NASA Technical Reports Server (NTRS)

Johnson, Thomas A.; Nguyen, Dung Phu Chi; Cuda, Vince; Freesland, Doug

1994-01-01

The objective of this study is to model the on-orbit vibration environment encountered by a SmallSat. Vibration control issues are common to the Earth observing, imaging, and microgravity communities. A spacecraft may contain dozens of support systems and instruments each a potential source of vibration. The quality of payload data depends on constraining vibration so that parasitic disturbances do not affect the payload's pointing or microgravity requirement. In practice, payloads are designed incorporating existing flight hardware in many cases with nonspecific vibration performance. Thus, for the development of a payload, designers require a thorough knowledge of existing mechanical devices and their associated disturbance levels. This study evaluates a SmallSat mission and seeks to answer basic questions concerning on-orbit vibration. Payloads were considered from the Earth observing, microgravity, and imaging communities. Candidate payload requirements were matched to spacecraft bus resources of present day SmallSats. From the set of candidate payloads, the representative payload GLAS (Geoscience Laser Altimeter System) was selected. The requirements of GLAS were considered very stringent for the 150 - 500 kg class of payloads. Once the payload was selected, a generic SmallSat was designed in order to accommodate the payload requirements (weight, size, power, etc.). This study seeks to characterize the on-orbit vibration environment of a SmallSat designed for this type of mission and to determine whether a SmallSat can provide the precision pointing and jitter control required for earth observing payloads.

40 CFR 63.1034 - Closed vent systems and control devices; or emissions routed to a fuel gas system or process...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Closed vent systems and control devices; or emissions routed to a fuel gas system or process standards. 63.1034 Section 63.1034 Protection... stringent. The 20 parts per million by volume standard is not applicable to the provisions of § 63.1016. (ii...

40 CFR 63.1034 - Closed vent systems and control devices; or emissions routed to a fuel gas system or process...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Closed vent systems and control devices; or emissions routed to a fuel gas system or process standards. 63.1034 Section 63.1034 Protection... stringent. The 20 parts per million by volume standard is not applicable to the provisions of § 63.1016. (ii...

Continuous reduction of cyclic adsorbed and desorbed NO(x) in diesel emission using nonthermal plasma.

PubMed

Kuwahara, Takuya; Nakaguchi, Harunobu; Kuroki, Tomoyuki; Okubo, Masaaki

2016-05-05

Considering the recent stringent regulations governing diesel NO(x) emission, an aftertreatment system for the reduction of NO(x) in the exhaust gas has been proposed and studied. The proposed system is a hybrid method combining nonthermal plasma and NOx adsorbent. The system does not require precious metal catalysts or harmful chemicals such as urea and ammonia. In the present system, NO(x) in diesel emission is treated by adsorption and desorption by adsorbent as well as nonthermal plasma reduction. In addition, the remaining NO(x) in the adsorbent is desorbed again in the supplied air by residual heat. The desorbed NO(x) in air recirculates into the intake of the engine, and this process, i.e., exhaust gas components' recirculation (EGCR) achieves NO(x) reduction. Alternate utilization of two adsorption chambers in the system can achieve high-efficiency NO(x) removal continuously. An experiment with a stationary diesel engine for electric power generation demonstrates an energy efficiency of 154 g(NO2)/kWh for NO(x) removal and continuous NO(x) reduction of 70.3%. Considering the regulation against diesel emission in Japan, i.e., the new regulation to be imposed on vehicles of 3.5-7.5 ton since 2016, the present aftertreatment system fulfills the requirement with only 1.0% of engine power. Copyright © 2016. Published by Elsevier B.V.

Are More Stringent NCLB State Accountability Systems Associated with Better Student Outcomes? An Analysis of NAEP Results across States

ERIC Educational Resources Information Center

Wei, Xin

2012-01-01

This study developed a comprehensive measure of the stringency level of NCLB states' accountability systems, including the strength of their annual measurable objectives, confidence intervals, performance indexing, retesting, minimum subgroup size, and the difficulty levels of proficiency standards. This study related accountability stringency in…

76 FR 69734 - Public Water System Supervision Program Revision for the State of New Mexico

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-09

... Water System Supervision Program. New Mexico has adopted the Lead and Copper Rule Short Term Revisions... water. EPA has determined that this rule revision submitted by New Mexico is no less stringent than the... the following offices: New Mexico Environment Department, Drinking Water Bureau, 525 Camino De Los...

Service-Oriented Architecture (SOA) Instantiation within a Hard Real-Time, Deterministic Combat System Environment

ERIC Educational Resources Information Center

Moreland, James D., Jr

2013-01-01

This research investigates the instantiation of a Service-Oriented Architecture (SOA) within a hard real-time (stringent time constraints), deterministic (maximum predictability) combat system (CS) environment. There are numerous stakeholders across the U.S. Department of the Navy who are affected by this development, and therefore the system…

Advances in structural monitoring with Global Positioning System technology: 1997-2006

NASA Astrophysics Data System (ADS)

Ogaja, Clement; Li, Xiaojing; Rizos, Chris

2007-11-01

Over the last decade, users of the Global Positioning System (GPS) have developed the technology capable of meeting stringent requirements to study the dynamics of tall buildings, towers, and bridges during earthquakes, wind-induced deformation and traffic loading. Dynamic measurements of relative displacements of structures is currently possible using real-time kinematic (RTK) positioning techniques, now advanced to record typically at 10-20 Hz (or higher - e.g., 100 Hz) with an accuracy of ±1 cm horizontally and ±2 cm vertically. With further advances in the technology and improvements in sampling capability, it is possible to meet the needs of real-time displacement information for the structural engineering community. After a decade of great strides in proving the feasibility of the technology, focus is moving to sensor integration and operational systems. Several investigators are now routinely researching the integration of GPS with other sensors (accelerometers, fibre optics, pseudolites, etc.) to utilise the complementary benefits and overcome limitations of the individual systems. Examples of real-time operational systems exist to demonstrate the significance of GPS technology in measuring the dynamic behaviour of large engineering structures.

Vibration isolation and dual-stage actuation pointing system for space precision payloads

NASA Astrophysics Data System (ADS)

Kong, Yongfang; Huang, Hai

2018-02-01

Pointing and stability requirements for future space missions are becoming more and more stringent. This work follows the pointing control method which consists of a traditional spacecraft attitude control system and a payload active pointing loop, further proposing a vibration isolation and dual-stage actuation pointing system for space precision payloads based on a soft Stewart platform. Central to the concept is using the dual-stage actuator instead of the traditional voice coil motor single-stage actuator to improve the payload active pointing capability. Based on a specified payload, the corresponding platform was designed to be installed between the spacecraft bus and the payload. The performance of the proposed system is demonstrated by preliminary closed-loop control investigations in simulations. With the ordinary spacecraft bus, the line-of-sight pointing accuracy can be controlled to below a few milliarcseconds in tip and tilt. Meanwhile, utilizing the voice coil motor with the softening spring in parallel, which is a portion of the dual-stage actuator, the system effectively achieves low-frequency motion transmission and high-frequency vibration isolation along the other four degree-of-freedom directions.

Dual-Layer Video Encryption using RSA Algorithm

NASA Astrophysics Data System (ADS)

Chadha, Aman; Mallik, Sushmit; Chadha, Ankit; Johar, Ravdeep; Mani Roja, M.

2015-04-01

This paper proposes a video encryption algorithm using RSA and Pseudo Noise (PN) sequence, aimed at applications requiring sensitive video information transfers. The system is primarily designed to work with files encoded using the Audio Video Interleaved (AVI) codec, although it can be easily ported for use with Moving Picture Experts Group (MPEG) encoded files. The audio and video components of the source separately undergo two layers of encryption to ensure a reasonable level of security. Encryption of the video component involves applying the RSA algorithm followed by the PN-based encryption. Similarly, the audio component is first encrypted using PN and further subjected to encryption using the Discrete Cosine Transform. Combining these techniques, an efficient system, invulnerable to security breaches and attacks with favorable values of parameters such as encryption/decryption speed, encryption/decryption ratio and visual degradation; has been put forth. For applications requiring encryption of sensitive data wherein stringent security requirements are of prime concern, the system is found to yield negligible similarities in visual perception between the original and the encrypted video sequence. For applications wherein visual similarity is not of major concern, we limit the encryption task to a single level of encryption which is accomplished by using RSA, thereby quickening the encryption process. Although some similarity between the original and encrypted video is observed in this case, it is not enough to comprehend the happenings in the video.

A Ten-Meter Ground-Station Telescope for Deep-Space Optical Communications: A Preliminary Design

NASA Technical Reports Server (NTRS)

Britcliffe, M.; Hoppe, D.; Roberts, W.; Page, N.

2001-01-01

This article describes a telescope design for a 10-m optical ground station for deep-space communications. The design for a direct-detection optical communications telescope differs dramatically from a telescope for imaging applications. In general, the requirements for optical manufacturing and tracking performance are much less stringent for direct detection of optical signals. The technical challenge is providing a design that will operate in the daytime/nighttime conditions required for a Deep Space Network tracking application. The design presented addresses these requirements. The design will provide higher performance at lower cost than existing designs.

Process for fabrication of large titanium diboride ceramic bodies

DOEpatents

Moorhead, Arthur J.; Bomar, E. S.; Becher, Paul F.

1989-01-01

A process for manufacturing large, fully dense, high purity TiB.sub.2 articles by pressing powders with a sintering aid at relatively low temperatures to reduce grain growth. The process requires stringent temperature and pressure applications in the hot-pressing step to ensure maximum removal of sintering aid and to avoid damage to the fabricated article or the die.

A polyketide synthase gene and an aspartate kinase like gene are required for the biosynthesis of fusaric acid in Fusarium Oxysporum f. sp. Vasinfectum

USDA-ARS?s Scientific Manuscript database

A genetically unique strain of the Fusarium wilt pathogen was first recognized in wilted and dead Upland cotton seedlings in Australia in 1993. Since that time the disease spread rapidly despite stringent containment practices. The Australian biotype isolates of Fusarium oxysporum f. sp. vasinfec...

Rugged, Tunable Extended-Cavity Diode Laser

NASA Technical Reports Server (NTRS)

Moore, Donald; Brinza, David; Seidel, David; Klipstein, William; Choi, Dong Ho; Le, Lam; Zhang, Guangzhi; Iniguez, Roberto; Tang, Wade

2007-01-01

A rugged, tunable extended-cavity diode laser (ECDL) has been developed to satisfy stringent requirements for frequency stability, notably including low sensitivity to vibration. This laser is designed specifically for use in an atomic-clock experiment to be performed aboard the International Space Station (ISS). Lasers of similar design would be suitable for use in terrestrial laboratories engaged in atomic-clock and atomic-physics research.

The Limits of Civic Education: The Divergent Implications of Political and Comprehensive Liberalism

ERIC Educational Resources Information Center

Fowler, Tim

2011-01-01

Education has become one of the foremost arenas in which political liberals attempt to differentiate their account from that of comprehensive liberals. Rawls posits that the requirements of his theory, as laid out in "Political Liberalism," will be far less stringent than those of liberals such as Kant, Mill or Joseph Raz. However, a number of…

The Human Rights Context for Ethical Requirements for Involving People with Intellectual Disability in Medical Research

ERIC Educational Resources Information Center

Iacono, T.; Carling-Jenkins, R.

2012-01-01

Background: The history of ethical guidelines addresses protection of human rights in the face of violations. Examples of such violations in research involving people with intellectual disabilities (ID) abound. We explore this history in an effort to understand the apparently stringent criteria for the inclusion of people with ID in research, and…

A Study of Covert Communications in Space Platforms Hosting Government Payloads

DTIC Science & Technology

2015-02-01

possible adversarial actions (e.g., malicious software co- resident on the commercial host). Threats to the commercial supply chain are just one... supply chain to either create or exploit channel vulnerabilities. For government hosted payload missions, the critical payload data are encrypted...access to space by hosting government- supplied payloads on commercial space platforms. These commercially hosted payloads require stringent

Evaluating the fate of mercury and other metals across the life-cycle stages from the use of FGD gypsum for wallboard production

EPA Science Inventory

In 2007, 12.3 million tons of flue gas desulfurization (FGD) gypsum was produced due to air emission controls at coal-fired power plants. With increasing use of wet scrubbers in response to more stringent air pollution control requirements, FGD gypsum production is expected to in...

75 FR 81765 - Safety Standards for Full-Size Baby Cribs and Non-Full-Size Baby Cribs; Final Rule

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-28

...Section 104(b) of the Consumer Product Safety Improvement Act of 2008 (``CPSIA'') requires the United States Consumer Product Safety Commission (``CPSC,'' ``Commission,'' or ``we'') to promulgate consumer product safety standards for durable infant or toddler products. These standards are to be ``substantially the same as'' applicable voluntary standards or more stringent than the voluntary standard if the Commission concludes that more stringent requirements would further reduce the risk of injury associated with the product. The Commission is issuing safety standards for full-size and non-full-size baby cribs in response to the direction under section 104(b) of the CPSIA.\\1\\ Section 104(c) of the CPSIA specifies that the crib standards will cover used as well as new cribs. The crib standards will apply to anyone who manufactures, distributes, or contracts to sell a crib; to child care facilities, family child care homes, and others holding themselves out to be knowledgeable about cribs; to anyone who leases, sublets, or otherwise places a crib in the stream of commerce; and to owners and operators of places of public accommodation affecting commerce. ---------------------------------------------------------------------------

Power Enhancement in High Dimensional Cross-Sectional Tests

PubMed Central

Fan, Jianqing; Liao, Yuan; Yao, Jiawei

2016-01-01

We propose a novel technique to boost the power of testing a high-dimensional vector H : θ = 0 against sparse alternatives where the null hypothesis is violated only by a couple of components. Existing tests based on quadratic forms such as the Wald statistic often suffer from low powers due to the accumulation of errors in estimating high-dimensional parameters. More powerful tests for sparse alternatives such as thresholding and extreme-value tests, on the other hand, require either stringent conditions or bootstrap to derive the null distribution and often suffer from size distortions due to the slow convergence. Based on a screening technique, we introduce a “power enhancement component”, which is zero under the null hypothesis with high probability, but diverges quickly under sparse alternatives. The proposed test statistic combines the power enhancement component with an asymptotically pivotal statistic, and strengthens the power under sparse alternatives. The null distribution does not require stringent regularity conditions, and is completely determined by that of the pivotal statistic. As specific applications, the proposed methods are applied to testing the factor pricing models and validating the cross-sectional independence in panel data models. PMID:26778846

Research notes : capacity of aging bent caps.

DOT National Transportation Integrated Search

2008-10-01

Many conventionally reinforced concrete deck girder (RCDG) bridges were built in the United States during the construction of the interstate highway system in the 1950s. Designs followed the AASHO standard of the time, which were less stringent than ...

Magnetic Testing, and Modeling, Simulation and Analysis for Space Applications

NASA Technical Reports Server (NTRS)

Boghosian, Mary; Narvaez, Pablo; Herman, Ray

2012-01-01

The Aerospace Corporation (Aerospace) and Lockheed Martin Space Systems (LMSS) participated with Jet Propulsion Laboratory (JPL) in the implementation of a magnetic cleanliness program of the NASA/JPL JUNO mission. The magnetic cleanliness program was applied from early flight system development up through system level environmental testing. The JUNO magnetic cleanliness program required setting-up a specialized magnetic test facility at Lockheed Martin Space Systems for testing the flight system and a testing program with facility for testing system parts and subsystems at JPL. The magnetic modeling, simulation and analysis capability was set up and performed by Aerospace to provide qualitative and quantitative magnetic assessments of the magnetic parts, components, and subsystems prior to or in lieu of magnetic tests. Because of the sensitive nature of the fields and particles scientific measurements being conducted by the JUNO space mission to Jupiter, the imposition of stringent magnetic control specifications required a magnetic control program to ensure that the spacecraft's science magnetometers and plasma wave search coil were not magnetically contaminated by flight system magnetic interferences. With Aerospace's magnetic modeling, simulation and analysis and JPL's system modeling and testing approach, and LMSS's test support, the project achieved a cost effective approach to achieving a magnetically clean spacecraft. This paper presents lessons learned from the JUNO magnetic testing approach and Aerospace's modeling, simulation and analysis activities used to solve problems such as remnant magnetization, performance of hard and soft magnetic materials within the targeted space system in applied external magnetic fields.

Crash-resistant fuel system effectiveness in civil helicopter crashes.

PubMed

Hayden, Mark S; Shanahan, Dennis F; Chen, Li-Hui; Baker, Susan P

2005-08-01

Crash-resistant fuel systems (CRFS) have demonstrated close to 100% effectiveness in survivable crashes of Army helicopters, but the technology has been slow to transfer into the civil helicopter arena. Federal standards for civil helicopter CRFS are less stringent than those for military helicopters. A reduction in standards for CRFS in military helicopters is being considered. The goal of this study was to determine whether crashes of civil helicopters with CRFS are less likely to result in post-crash fire than crashes of those without. Crashes of civil helicopters during 1982-2004 were analyzed, comparing Bell 206 helicopters manufactured with CRFS with Aerospatial 350 helicopters manufactured during the same period (post-1981), but lacking CRFS. Bell 206 helicopters with CRFS were also compared with earlier models without CRFS. The highest proportion of crashes with post-crash fires (11.3%) was in AS-350s manufactured after 1981 (non-CRFS), and the lowest (3.7%) was in Bell 206s (with CRFS) [unadjusted risk ratio (RR) = 3.3, 95% confidence interval (CI) = 1.04, 10.50; adjusted for light and weather, RR = 2.81, Cl = 0.82, 9.69]. Earlier models of Bell 206s without CRFS had higher risk of post-crash fire than post-1981 models with CRFS (7.4% vs. 3.7%; adjusted RR = 2.11, Cl = 0.82, 5.45). The results of this study suggest a better performance, in terms of post-crash fire prevention, of CRFS-equipped civil helicopters as compared with those without CRFS. It is possible that CRFS in civil helicopters have not achieved the same degree of effectiveness as CRFS in military helicopters. CRFS should be used more widely in civil helicopters. The more stringent CRFS requirements for military helicopters should not be reduced without further research.

Characteristics of typical non-road machinery emissions in China by using portable emission measurement system.

PubMed

Fu, Mingliang; Ge, Yunshan; Tan, Jianwei; Zeng, Tao; Liang, Bin

2012-10-15

Non-road machinery, especially construction equipment could be an important pollutant source of the deterioration in air quality in Chinese urban areas due to its large quantity and to the absence of stringent emission requirements. In this study, emission tests were performed on 12 excavators and 8 wheel loaders by using portable emission measurement system (PEMS) to determine their emission characteristics. The typical operating modes were categorized as idling mode, moving mode and working mode. Compared with those during idling and moving modes, the average time-based emission factors during working mode of HC were 2.61 and 1.27 times higher, NO(x) were 3.66 and 1.36 times higher, and PM were 4.05 and 1.95 times higher, respectively. Under all conditions, categories of the measured emissions increased with the rise in engine power. Compared with those of Stage I emission standard equipment, gaseous emissions and PM emitted from Stage II emission standard equipment were lower. The results indicated that, from Stage I to Stage II, the average reductions of HC, NO(x) and PM were 56%, 37% and 29% for the working mode, respectively. Those results also demonstrated the effectiveness of emission control regulation and the improvement of emission control technology. The data and tests show that the longer the accumulated working hours, the higher HC and NO(x) average fuel-based emission factors are. The emissions measured from the construction vehicles employed in this study were higher than the data collected in previous studies, which shows that it is critical for the government to put into effect more stringent emission regulations to further improve the air quality in Chinese urban areas. Copyright © 2012 Elsevier B.V. All rights reserved.

Tsunami Detection Systems for International Requirements

NASA Astrophysics Data System (ADS)

Lawson, R. A.

2007-12-01

Results are presented regarding the first commercially available, fully operational, tsunami detection system to have passed stringent U.S. government testing requirements and to have successfully demonstrated its ability to detect an actual tsunami at sea. Spurred by the devastation of the December 26, 2004, Indian Ocean tsunami that killed more than 230,000 people, the private sector actively supported the Intergovernmental Oceanographic Commission's (IOC"s) efforts to develop a tsunami warning system and mitigation plan for the Indian Ocean region. As each country in the region developed its requirements, SAIC recognized that many of these underdeveloped countries would need significant technical assistance to fully execute their plans. With the original focus on data fusion, consequence assessment tools, and warning center architecture, it was quickly realized that the cornerstone of any tsunami warning system would be reliable tsunami detection buoys that could meet very stringent operational standards. Our goal was to leverage extensive experience in underwater surveillance and oceanographic sensing to produce an enhanced and reliable deep water sensor that could meet emerging international requirements. Like the NOAA Deep-ocean Assessment and Recording of Tsunamis (DART TM ) buoy, the SAIC Tsunami Buoy (STB) system consists of three subsystems: a surfaccommunications buoy subsystem, a bottom pressure recorder subsystem, and a buoy mooring subsystem. With the operational success that DART has demonstrated, SAIC decided to build and test to the same high standards. The tsunami detection buoy system measures small changes in the depth of the deep ocean caused by tsunami waves as they propagate past the sensor. This is accomplished by using an extremely sensitive bottom pressure sensor/recorder to measure very small changes in pressure as the waves move past the buoy system. The bottom pressure recorder component includes a processor with algorithms that recognize these characteristics, and then immediately alerts a tsunami warning center through the communications buoy when the processor senses one of these waves. In addition to the tsunami detection buoy system, an end-to-end tsunami warning system was developed that builds upon the country's existing disaster warning infrastructure. This warning system includes 1) components that receive, process, and analyze buoy, seismic and tide gauge data; 2) predictive tools and a consequence assessment tool set to provide decision support; 3) operation center design and implementation; and 4) tsunami buoy operations and maintenance support. The first buoy was deployed Oct. 25, 2006, approximately 200 nautical miles west of San Diego in 3,800 meters of water. Just three weeks later, it was put to the test during an actual tsunami event. On Nov. 15, 2006, an 8.3 magnitude earthquake rocked the Kuril Islands, located between Japan and the Kamchatka Peninsula of Russia. That quake generated a small tsunami. Waves from the tsunami propagated approximately 4,000 nautical miles across the Pacific Ocean in about nine hours-- a speed of about 445 nautical miles per hour when this commercial buoy first detected them. Throughout that event, the tsunami buoy system showed excellent correlation with data collected by a NOAA DART buoy located 28 nautical miles north of it. Subsequent analysis revealed that the STB matched DART operational capabilities and performed flawlessly. The buoy proved its capabilities again on Jan. 13, 2007, when an 8.1 magnitude earthquake occurred in the same region, and the STB detected the seismic event. As a result of the successes of this entire project, SAIC recently applied for and received a license from NOAA to build DART systems.

Initial Closed Operation of the CELSS Test Facility Engineering Development Unit

NASA Technical Reports Server (NTRS)

Kliss, Mark

1995-01-01

As part of the NASA Controlled Ecological Life Support System (CELSS) Program, a CELSS Test Facility (CTF) is being planned for installation on the Space Station. The CTF will be used to provide data on the productivity and efficiency of a variety of CELSS higher plant crops grown sequentially from seed to harvest in the microgravity environment of the Space Station. Stringent environmental control will be maintained while fundamental crop productivity issues, such as carbon dioxide uptake and oxygen production rates, water transpiration rates, and biomass accumulation rates are obtained for comparison with ground-based data. In order to obtain an early realistic determination of the subsystem and system requirements necessary to provide the appropriate environmental conditions specified for CTF crop productivity experiments, an Engineering Development Unit (EDU) has been constructed and is undergoing initial operational testing at NASA Ames Research Center. The EDU is a ground-based testbed which will be used to characterize the integrated performance of major subsystem technologies, to evaluate hardware candidates and control strategies required for the CTF, and to further define the ability to meet CTF requirements within present Space Station constraints. This paper describes the initial closed operational testing of the EDU. Measured performance data are compared with the specified functional requirements and results from initial closed testing are presented. Plans for future science and technology testing are discussed.

The nylon scintillator containment vessels for the Borexino solar neutrino experiment

NASA Astrophysics Data System (ADS)

Cadonati, L.; Calaprice, F.; Galbiati, C.; Pocar, A.; Shutt, T.

2014-06-01

The neutrino event rate in the Borexino scintillator is very low ( 0.5 events per day per ton) and concentrated in an energy region well below the 2.6 MeV threshold of natural radioactivity. The intrinsic radioactive contaminants in the photomultipliers (PMTs), in the Stainless Steel Sphere, and in other detector components, play special requirements on the system required to contain the scintillator. The liquid scintillator must be shielded from the Stainless Steel Sphere and from the PMTs by a thick barrier of buffer fluid. The fluid barrier, in addition, needs to be segmented in order to contain migration of radon and daughters emanated by the Stainless Steel Sphere and by the PMTs. These requirements were met by designing and building two spherical vessel made of thin nylon film. The inner vessel contains the scintillator, separating it from the surrounding buffer. The buffer region itself is divided into two concentric shells by the second, outer nylon vessel. In addition, the two nylon vessels must satisfy stringent requirements for radioactivity and for mechanical, optical and chemical properties. This paper describes the requirements of the the nylon vessels for the Borexino experiment and offers a brief overview of the construction methods adopted to meet those requirements.

Design and implementation of robust decentralized control laws for the ACES structure at Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

Collins, Emmanuel G., Jr.; Phillips, Douglas; Hyland, David C.

1990-01-01

An experiment was conducted to design controllers that would provide substantial reduction of line-of-sight control errors. The satisfaction of this objective required the controllers to attenuate the beam vibration significantly. Particular emphasis was placed on controller simplicity (i.e., reduced-order and decentralized controller architectures). Complexity reduction in control law implementation is of paramount interest due to stringent limitations on throughput of even state-of-the-art space qualified processors. The results of this experiment successfully demonstrate active vibrator control for a flexible structure. The testbed is the ACES structure at the NASA Marshall Space Flight Center. The ACES structure is dynamically traceable to future space systems and especially allows the study of line-of-sight control issues.

Beam alignment based on two-dimensional power spectral density of a near-field image.

PubMed

Wang, Shenzhen; Yuan, Qiang; Zeng, Fa; Zhang, Xin; Zhao, Junpu; Li, Kehong; Zhang, Xiaolu; Xue, Qiao; Yang, Ying; Dai, Wanjun; Zhou, Wei; Wang, Yuanchen; Zheng, Kuixing; Su, Jingqin; Hu, Dongxia; Zhu, Qihua

2017-10-30

Beam alignment is crucial to high-power laser facilities and is used to adjust the laser beams quickly and accurately to meet stringent requirements of pointing and centering. In this paper, a novel alignment method is presented, which employs data processing of the two-dimensional power spectral density (2D-PSD) for a near-field image and resolves the beam pointing error relative to the spatial filter pinhole directly. Combining this with a near-field fiducial mark, the operation of beam alignment is achieved. It is experimentally demonstrated that this scheme realizes a far-field alignment precision of approximately 3% of the pinhole size. This scheme adopts only one near-field camera to construct the alignment system, which provides a simple, efficient, and low-cost way to align lasers.

Bacteriophages in food fermentations: new frontiers in a continuous arms race.

PubMed

Samson, Julie E; Moineau, Sylvain

2013-01-01

Phage contamination represents an important risk to any process requiring bacterial growth, particularly in the biotechnology and food industries. The presence of unwanted phages may lead to manufacturing delays, lower quality product, or, in the worst cases, total production loss. Thus, constant phage monitoring and stringent application of the appropriate control measures are indispensable. In fact, a systematic preventive approach to phage contamination [phage analysis and critical control points (PACCP)] should be put in place. In this review, sources of phage contamination and novel phage detection methods are described, with an emphasis on bacterial viruses that infect lactic acid bacteria used in food fermentations. Recent discoveries related to antiphage systems that are changing our views on phage-host interactions are highlighted. Finally, future directions are also discussed.

Securing Mobile Networks in an Operational Setting

NASA Technical Reports Server (NTRS)

Ivancic, William D.; Stewart, David H.; Bell, Terry L.; Paulsen, Phillip E.; Shell, Dan

2004-01-01

This paper describes a network demonstration and three month field trial of mobile networking using mobile-IPv4. The network was implemented as part of the US Coast Guard operational network which is a ".mil" network and requires stringent levels of security. The initial demonstrations took place in November 2002 and a three month field trial took place from July through September of 2003. The mobile network utilized encryptors capable of NSA-approved Type 1 algorithms, mobile router from Cisco Systems and 802.11 and satellite wireless links. This paper also describes a conceptual architecture for wide-scale deployment of secure mobile networking in operational environments where both private and public infrastructure is used. Additional issues presented include link costs, placement of encryptors and running routing protocols over layer-3 encryption devices.

Quantum random number generation for loophole-free Bell tests

NASA Astrophysics Data System (ADS)

Mitchell, Morgan; Abellan, Carlos; Amaya, Waldimar

2015-05-01

We describe the generation of quantum random numbers at multi-Gbps rates, combined with real-time randomness extraction, to give very high purity random numbers based on quantum events at most tens of ns in the past. The system satisfies the stringent requirements of quantum non-locality tests that aim to close the timing loophole. We describe the generation mechanism using spontaneous-emission-driven phase diffusion in a semiconductor laser, digitization, and extraction by parity calculation using multi-GHz logic chips. We pay special attention to experimental proof of the quality of the random numbers and analysis of the randomness extraction. In contrast to widely-used models of randomness generators in the computer science literature, we argue that randomness generation by spontaneous emission can be extracted from a single source.

Mission in the works promises precise global topographic data

USGS Publications Warehouse

Farr, T.; Evans, D.; Zebker, H.; Harding, D.; Bufton, J.; Dixon, T.; Vetrella, S.; Gesch, D.B.

1995-01-01

Significant deficiencies in the quality of today's topographic data severely limit scientific applications. Very few available data sets meet the stringent requirements of 10–30 m for global digital topography and 5 m or better vertical accuracy, and existing satellite systems are unlikely to fulfill these requirements. The Joint Topographic Science Working Group, appointed by NASA and the Italian Space Agency, concluded that radar interferometry coupled with a laser altimeter would be the most promising approach for improving data quality. By providing its own illumination at a wavelength Ion g enough to (e.g., λ = 25 cm) to penetrate clouds and rain, the interferometer would provide a global, uniform high-quality topographic data set. One mission under study, TOPSAT, is well positioned to fill this niche and promises to pave the way toward a more standardized and precise topographic database. TOPSAT would be an international mission, designed to make use of recent technology advances in such programs as NASA's New Millennium. It could be ready to launch by the end of this decade.

Flight Mechanics of the Entry, Descent and Landing of the ExoMars Mission

NASA Technical Reports Server (NTRS)

HayaRamos, Rodrigo; Boneti, Davide

2007-01-01

ExoMars is ESA's current mission to planet Mars. A high mobility rover and a fixed station will be deployed on the surface of Mars. This paper regards the flight mechanics of the Entry, Descent and Landing (EDL) phases used for the mission analysis and design of the Baseline and back-up scenarios of the mission. The EDL concept is based on a ballistic entry, followed by a descent under parachutes and inflatable devices (airbags) for landing. The mission analysis and design is driven by the flexibility in terms of landing site, arrival dates and the very stringent requirement in terms of landing accuracy. The challenging requirements currently imposed to the mission need innovative analysis and design techniques to support system design trade-offs to cope with the variability in entry conditions. The concept of the Global Entry Corridor has been conceived, designed, implemented and successfully validated as a key tool to provide a global picture of the mission capabilities in terms of landing site reachability.

Characterization of a Track-and-Hold Amplifier for Application to a High Performance SAR

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

DUBBERT, DALE F.; HARDIN, TERRY LYNN; DELAPLAIN, GILBERT G.

2002-07-01

A Synthetic Aperture Radar (SAR) which employs direct IF sampling can significantly reduce the complexity of the analog electronics prior to the analog-to-digital converter (ADC). For relatively high frequency IF bands, a wide-bandwidth track-and-hold amplifier (THA) is required prior to the ADC. The THA functions primarily as a means of converting, through bandpass sampling, the IF signal to a baseband signal which can be sampled by the ADC. For a wide-band, high dynamic-range receiver system, such as a SAR receiver, stringent performance requirements are placed on the THA. We first measure the THA parameters such as gain, gain compression, third-ordermore » intercept (TOI), signal-to-noise ratio (SNR), spurious-free dynamic-range (SFDR), noise figure (NF), and phase noise. The results are then analyzed in terms of their respective impact on the overall performance of the SAR. The specific THA under consideration is the Rockwell Scientific RTH010.« less

The use of computer-generated color graphic images for transient thermal analysis. [for hypersonic aircraft

NASA Technical Reports Server (NTRS)

Edwards, C. L. W.; Meissner, F. T.; Hall, J. B.

1979-01-01

Color computer graphics techniques were investigated as a means of rapidly scanning and interpreting large sets of transient heating data. The data presented were generated to support the conceptual design of a heat-sink thermal protection system (TPS) for a hypersonic research airplane. Color-coded vector and raster displays of the numerical geometry used in the heating calculations were employed to analyze skin thicknesses and surface temperatures of the heat-sink TPS under a variety of trajectory flight profiles. Both vector and raster displays proved to be effective means for rapidly identifying heat-sink mass concentrations, regions of high heating, and potentially adverse thermal gradients. The color-coded (raster) surface displays are a very efficient means for displaying surface-temperature and heating histories, and thereby the more stringent design requirements can quickly be identified. The related hardware and software developments required to implement both the vector and the raster displays for this application are also discussed.

ICESat-2 ATLAS Beam Steering Mechanism (BSM)

NASA Technical Reports Server (NTRS)

Hinkle, Matthew

2015-01-01

This work covers the design and test of a beam steering mechanism (BSM) used to accurately guide a laser on the Advanced Topographic Laser Altimeter System (ATLAS) down to Earth in order to measure elevation. It describes the main components in the BSM that allows it to perform and meet stringent requirements. Requirements of the BSM include two-axis steering of the transmitted laser beam, +-5000 uRad mechanical motion in each axis, and 1.5 uRad RMS pointing stability among many other requirements. The BSM uses four voice coil actuators in order to locate the mirror at the angle we need. There are four Differential Position Sensors that determine the position and angle of the mirror at all times. These sensors were verified through optical testing in both ambient and thermal conditions. Testing and extensive analyses were performed on the two-axis flexure throughout the program to check flexure thickness, positive margins, and infinite life. The mirror mount design has been modified to eliminate radial preload, while incorporating a titanium wave spring to provide an axial preload of 10.8N. The BSM underwent multiple tests in order to verify all components work as required under various conditions.

IRST: a key system in modern warfare

NASA Astrophysics Data System (ADS)

Missirian, Jean-Michel; Ducruet, Laurent

1997-08-01

A naval infra red search and track (IRST) system is a passive surveillance device capable of detecting and tracking air and surface threats in the region where electromagnetic sensors are less efficient, typically within a few degrees around the horizon. The evolution in anti ship sea skimming missiles performances has outlined the benefit that can be gained from infrared systems in ship self-defense. The complementary nature of radar and IRST systems can also be exploited to full advantage in the field of multisensor data fusion. The combined use of radar and infrared secures the detection by redundancy of data; it substantially enhances target tracking, classification and identification and reduces the combat system's reaction time. Designing an IRST implies matching technical choices with operational requirements, and this under increasingly stringent cost constraints. This paper first reminds the benefits that can be obtained with an IRST system in the context of modern naval warfare, then retraces the evolutions from the first generation IRST systems, such as VAMPIR, to the second-generation systems now entering service. A general presentation of the current SAGEM SA IRST family is also made for naval, air and ground-based applications.

The human rights context for ethical requirements for involving people with intellectual disability in medical research.

PubMed

Iacono, T; Carling-Jenkins, R

2012-11-01

The history of ethical guidelines addresses protection of human rights in the face of violations. Examples of such violations in research involving people with intellectual disabilities (ID) abound. We explore this history in an effort to understand the apparently stringent criteria for the inclusion of people with ID in research, and differences between medical and other research within a single jurisdiction. The history of the Helsinki Declaration and informed consent within medical research, and high-profile examples of ethical misconduct involving people with ID and other groups are reviewed. The UN Convention on the Rights of Persons with Disabilities is then examined for its research implications. This background is used to examine a current anomaly within an Australian context for the inclusion of people with ID without decisional capacity in medical versus other types of research. Ethical guidelines have often failed to protect the human rights of people with ID and other vulnerable groups. Contrasting requirements within an Australian jurisdiction for medical and other research would seem to have originated in early deference to medical authority for making decisions on behalf of patients. Stringent ethical requirements are likely to continue to challenge researchers in ID. A human rights perspective provides a framework for engaging both researchers and vulnerable participant groups. © 2012 The Authors. Journal of Intellectual Disability Research © 2012 Blackwell Publishing Ltd.

Lipophilic super-absorbent polymer gels as surface cleaners for oil and grease

USDA-ARS?s Scientific Manuscript database

Increasingly stringent environmental regulations on volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) demand the development of disruptive technologies for cleaning weapons systems and platforms. Currently employed techniques such as vapor degreasing, solvent, aqueous, or blast ...

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

Rowe, Nathan C; Younkin, James R; Pickett, Chris A

Radio-Frequency (RF) devices have revolutionized many aspects of modern industrial processes. RF technology can enable wireless communication for tag identification, sensor communication, and asset tracking. Radio-frequency identification (RFID) is a technology that utilizes wireless communication to interrogate and identify an electronic tag attached to an item in order to identify the item. The technology can come in many forms: passive or active tags, low to ultra-wideband frequencies, small paper-thin tags to brick-sized units, and simple tags or highly integrated sensor packages. RF technology, and specifically RFID, has been applied widely in commercial markets for inventory, supply chain management, and assetmore » tracking. Several recent studies have demonstrated the safeguards benefits of utilizing RFID versus conventional inventory tagging methods for tracking nuclear material. These studies have indicated that the RF requirements for safeguards functions are more stringent than the RF requirements for other inventory tracking and accounting applications. Additionally, other requirements must be addressed, including environmental and operating conditions, authentication, and tag location and attachment. Facility restrictions on radio spectrum, method of tag attachment, and sensitivity of the data collected impact the tag selection and system design. More important, the intended use of the system must be considered. The requirements for using RF to simply replace or supplement container identifiers such as bar codes that facilitate the inventory function will differ greatly from the requirements for deploying RF for unattended monitoring applications. Several studies have investigated these considerations to advance commercial RF devices for safeguards use, and a number of system concepts have been developed. This paper will provide an overview of past studies and current technologies, and will investigate the requirements, existing gaps, and several potential next steps for advancing RF techniques for safeguards use.« less

40 CFR 281.30 - New UST system design, construction, installation, and notification.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 27 2011-07-01 2011-07-01 false New UST system design, construction, installation, and notification. 281.30 Section 281.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) APPROVAL OF STATE UNDERGROUND STORAGE TANK PROGRAMS Criteria for No-Less-Stringent § 281.30 New UST...

40 CFR 281.30 - New UST system design, construction, installation, and notification.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 26 2010-07-01 2010-07-01 false New UST system design, construction, installation, and notification. 281.30 Section 281.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) APPROVAL OF STATE UNDERGROUND STORAGE TANK PROGRAMS Criteria for No-Less-Stringent § 281.30 New UST...

Multi-beam range imager for autonomous operations

NASA Technical Reports Server (NTRS)

Marzwell, Neville I.; Lee, H. Sang; Ramaswami, R.

1993-01-01

For space operations from the Space Station Freedom the real time range imager will be very valuable in terms of refuelling, docking as well as space exploration operations. For these applications as well as many other robotics and remote ranging applications, a small potable, power efficient, robust range imager capable of a few tens of km ranging with 10 cm accuracy is needed. The system developed is based on a well known pseudo-random modulation technique applied to a laser transmitter combined with a novel range resolution enhancement technique. In this technique, the transmitter is modulated by a relatively low frequency of an order of a few MHz to enhance the signal to noise ratio and to ease the stringent systems engineering requirements while accomplishing a very high resolution. The desired resolution cannot easily be attained by other conventional approaches. The engineering model of the system is being designed to obtain better than 10 cm range accuracy simply by implementing a high precision clock circuit. In this paper we present the principle of the pseudo-random noise (PN) lidar system and the results of the proof of experiment.

RC beams shear-strengthened with fabric-reinforced-cementitious-matrix (FRCM) composite

NASA Astrophysics Data System (ADS)

Loreto, Giovanni; Babaeidarabad, Saman; Leardini, Lorenzo; Nanni, Antonio

2015-12-01

The interest in retrofit/rehabilitation of existing concrete structures has increased due to degradation and/or introduction of more stringent design requirements. Among the externally-bonded strengthening systems fiber-reinforced polymers is the most widely known technology. Despite its effectiveness as a material system, the presence of an organic binder has some drawbacks that could be addressed by using in its place a cementitious binder as in fabric-reinforced cementitious matrix (FRCM) systems. The purpose of this paper is to evaluate the behavior of reinforced concrete (RC) beams strengthened in shear with U-wraps made of FRCM. An extensive experimental program was undertaken in order to understand and characterize this composite when used as a strengthening system. The laboratory results demonstrate the technical viability of FRCM for shear strengthening of RC beams. Based on the experimental and analytical results, FRCM increases shear strength but not proportionally to the number of fabric plies installed. On the other hand, FRCM failure modes are related with a high consistency to the amount of external reinforcement applied. Design considerations based on the algorithms proposed by ACI guidelines are also provided.

Transmission of multiplexed video signals in multimode optical fiber systems

NASA Technical Reports Server (NTRS)

White, Preston, III

1988-01-01

Kennedy Space Center has the need for economical transmission of two multiplexed video signals along multimode fiberoptic systems. These systems must span unusual distances and must meet RS-250B short-haul standards after reception. Bandwidth is a major problem and studies of the installed fibers, available LEDs and PINFETs led to the choice of 100 MHz as the upper limit for the system bandwidth. Optical multiplexing and digital transmission were deemed inappropriate. Three electrical multiplexing schemes were chosen for further study. Each of the multiplexing schemes included an FM stage to help meet the stringent S/N specification. Both FM and AM frequency division multiplexing methods were investigated theoretically and these results were validated with laboratory tests. The novel application of quadrature amplitude multiplexing was also considered. Frequency division multiplexing of two wideband FM video signal appears the most promising scheme although this application requires high power highly linear LED transmitters. Futher studies are necessary to determine if LEDs of appropriate quality exist and to better quantify performance of QAM in this application.

Understanding Beam Alignment in a Coherent Lidar System

NASA Technical Reports Server (NTRS)

Prasad, Narasimha S.; Roychoudhari, Chandrasekhar

2015-01-01

Optical beam alignment in a coherent lidar (or ladar) receiver system plays a critical role in optimizing its performance. Optical alignment in a coherent lidar system dictates the wavefront curvature (phase front) and Poynting vector) matching of the local oscillator beam with the incoming receiver beam on a detector. However, this alignment is often not easy to achieve and is rarely perfect. Furthermore, optical fibers are being increasingly used in coherent lidar system receivers for transporting radiation to achieve architectural elegance. Single mode fibers also require stringent mode matching for efficient light coupling. The detector response characteristics vary with the misalignment of the two pointing vectors. Misalignment can lead to increase in DC current. Also, a lens in front of the detector may exasperate phase front and Poynting vector mismatch. Non-Interaction of Waves, or the NIW property indicates the light beams do not interfere by themselves in the absence of detecting dipoles. In this paper, we will analyze the extent of misalignment on the detector specifications using pointing vectors of mixing beams in light of the NIW property.

Prevention of errors and user alienation in healthcare IT integration programmes.

PubMed

Benson, Tim

2007-01-01

The design, development and implementation stages of integrated computer projects require close collaboration between users and developers, but this is particularly difficult where there are multiple specialties, organisations and system suppliers. Users become alienated if they are not consulted, but consultation is meaningless if they cannot understand the specifications showing exactly what is proposed. We need stringent specifications that users and developers can review and check before most of the work is done. Avoidable errors lead to delays and cost over-runs. The number of errors is a function of the likelihood of misunderstanding any part of the specification, the number of individuals involved and the number of choices or options. One way to reduce these problems is to provide a conceptual design specification, comprising detailed Unified Modelling Language (UML) class and activity diagrams, data definitions and terminology, in addition to conventional technology-specific specifications. A conceptual design specification needs to be straightforward to understand and use, transparent and unambiguous. People find structured diagrams, such as maps, charts and blueprints, easier to use than reports or tables. Other desirable properties include being technology-independent, comprehensive, stringent, coherent, consistent, composed from reusable elements and computer-readable (XML). When users and developers share the same agreed conceptual design specification, this can be one of the master documents of a formal contract between the stakeholders. No extra meaning should be added during the later stages of the project life cycle.

Proceedings: Workshop on Environmental Considerations in the Life-Cycle of Paints and Coatings Held in Champaign, Illinois on September 9-10, 1986

DTIC Science & Technology

1988-07-01

MSDS or Material Safety Data Sheets from our suppliers and we are required to provide the same for our customers . We are required to train our personnel...non-sparking tools. Labels We protect our customers by labeling our materials in accordance with the NPCA Labeling Guide which is at least as...stringent as any federal or local regulations, by providing Material Safety Data Sheets and by providing customer assistance O when requested regarding safe

Debris control design achievements of the booster separation motors

NASA Technical Reports Server (NTRS)

Smith, G. W.; Chase, C. A.

1985-01-01

The stringent debris control requirements imposed on the design of the Space Shuttle booster separation motor are described along with the verification program implemented to ensure compliance with debris control objectives. The principal areas emphasized in the design and development of the Booster Separation Motor (BSM) relative to debris control were the propellant formulation and nozzle closures which protect the motors from aerodynamic heating and moisture. A description of the motor design requirements, the propellant formulation and verification program, and the nozzle closures design and verification are presented.

Dilution refrigeration for space applications

NASA Technical Reports Server (NTRS)

Israelsson, U. E.; Petrac, D.

1990-01-01

Dilution refrigerators are presently used routinely in ground based applications where temperatures below 0.3 K are required. The operation of a conventional dilution refrigerator depends critically on the presence of gravity. To operate a dilution refrigerator in space many technical difficulties must be overcome. Some of the anticipated difficulties are identified in this paper and possible solutions are described. A single cycle refrigerator is described conceptually that uses forces other than gravity to function and the stringent constraints imposed on the design by requiring the refrigerator to function on the earth without using gravity are elaborated upon.

On-orbit damage detection and health monitoring of large space trusses: Status and critical issues

NASA Technical Reports Server (NTRS)

Kashangaki, Thomas A. L.

1991-01-01

The long lifetimes, delicate nature and stringent pointing requirements of large space structures such as Space Station Freedom and geostationary Earth sciences platforms might require that these spacecraft be monitored periodically for possible damage to the load carrying structures. A review of the literature in damage detection and health monitoring of such structures is presented, along with a candidate structure to be used as a testbed for future work in this field. A unified notation and terminology is also proposed to facilitate comparisons between candidate methods.

Rapid Cycling CO2 and H2O Removal System for EMU

NASA Technical Reports Server (NTRS)

Alptekin, Gokhan; Cates, Matthew; Dubovik, Margarita; Gershanovich, Yevgenia; Paul, Heather; Thomas, Gretchen

2006-01-01

NASA's planned future missions set stringent demands on the design of the Portable Life Support Systems (PLSS), requiring dramatic reductions in weight, decreased reliance on supplies and greater flexibility on the types of missions. Use of regenerable systems that reduce weight and volume of the EMU is of critical importance to NASA, both for low orbit operations and for long duration manned missions. The CO2 and humidity control unit in the existing PLSS design is relatively large, since it has to remove 8 hours worth of CO2. If the sorbent regeneration can be carried out during the extravehicular activity (EVA) with a relatively high regeneration frequency, the size of the sorbent canister and weight can be significantly reduced. TDA Research, Inc. (TDA) is developing a compact, regenerable sorbent-based system to control CO2 and humidity in the space suit ventilation loop. The sorbent can be regenerated using space vacuum during the EVA, eliminating all duration-limiting elements in the life support system. This paper summarizes the results of the sorbent development and testing, and evaluation efforts. The results of a preliminary system analysis are also included, showing the size and volume reductions provided by the new system.

Testing stellar evolution models with detached eclipsing binaries

NASA Astrophysics Data System (ADS)

Higl, J.; Weiss, A.

2017-12-01

Stellar evolution codes, as all other numerical tools, need to be verified. One of the standard stellar objects that allow stringent tests of stellar evolution theory and models, are detached eclipsing binaries. We have used 19 such objects to test our stellar evolution code, in order to see whether standard methods and assumptions suffice to reproduce the observed global properties. In this paper we concentrate on three effects that contain a specific uncertainty: atomic diffusion as used for standard solar model calculations, overshooting from convective regions, and a simple model for the effect of stellar spots on stellar radius, which is one of the possible solutions for the radius problem of M dwarfs. We find that in general old systems need diffusion to allow for, or at least improve, an acceptable fit, and that systems with convective cores indeed need overshooting. Only one system (AI Phe) requires the absence of it for a successful fit. To match stellar radii for very low-mass stars, the spot model proved to be an effective approach, but depending on model details, requires a high percentage of the surface being covered by spots. We briefly discuss improvements needed to further reduce the freedom in modelling and to allow an even more restrictive test by using these objects.

Pathways to low-cost electrochemical energy storage: a comparison of aqueous and nonaqueous flow batteries

DOE PAGES

Darling, Robert M.; Gallagher, Kevin G.; Kowalski, Jeffrey A.; ...

2014-11-01

Energy storage is increasingly seen as a valuable asset for electricity grids composed of high fractions of intermittent sources, such as wind power or, in developing economies, unreliable generation and transmission services. However, the potential of batteries to meet the stringent cost and durability requirements for grid applications is largely unquantified. We investigate electrochemical systems capable of economically storing energy for hours and present an analysis of the relationships among technological performance characteristics, component cost factors, and system price for established and conceptual aqueous and nonaqueous batteries. We identified potential advantages of nonaqueous flow batteries over those based on aqueousmore » electrolytes; however, new challenging constraints burden the nonaqueous approach, including the solubility of the active material in the electrolyte. Requirements in harmony with economically effective energy storage are derived for aqueous and nonaqueous systems. The attributes of flow batteries are compared to those of aqueous and nonaqueous enclosed and hybrid (semi-flow) batteries. Flow batteries are a promising technology for reaching these challenging energy storage targets owing to their independent power and energy scaling, reliance on facile and reversible reactants, and potentially simpler manufacture as compared to established enclosed batteries such as lead–acid or lithium-ion.« less

Prototyping Control and Data Acquisition for the ITER Neutral Beam Test Facility

NASA Astrophysics Data System (ADS)

Luchetta, Adriano; Manduchi, Gabriele; Taliercio, Cesare; Soppelsa, Anton; Paolucci, Francesco; Sartori, Filippo; Barbato, Paolo; Breda, Mauro; Capobianco, Roberto; Molon, Federico; Moressa, Modesto; Polato, Sandro; Simionato, Paola; Zampiva, Enrico

2013-10-01

The ITER Neutral Beam Test Facility will be the project's R&D facility for heating neutral beam injectors (HNB) for fusion research operating with H/D negative ions. Its mission is to develop technology to build the HNB prototype injector meeting the stringent HNB requirements (16.5 MW injection power, -1 MeV acceleration energy, 40 A ion current and one hour continuous operation). Two test-beds will be built in sequence in the facility: first SPIDER, the ion source test-bed, to optimize the negative ion source performance, second MITICA, the actual prototype injector, to optimize ion beam acceleration and neutralization. The SPIDER control and data acquisition system is under design. To validate the main architectural choices, a system prototype has been assembled and performance tests have been executed to assess the prototype's capability to meet the control and data acquisition system requirements. The prototype is based on open-source software frameworks running under Linux. EPICS is the slow control engine, MDSplus is the data handler and MARTe is the fast control manager. The prototype addresses low and high-frequency data acquisition, 10 kS/s and 10 MS/s respectively, camera image acquisition, data archiving, data streaming, data retrieval and visualization, real time fast control with 100 μs control cycle and supervisory control.

Cluster: A fleet of four spacecraft to study plasma structures in three dimensions

NASA Technical Reports Server (NTRS)

Schmidt, R.; Goldstein, M. L.

1988-01-01

The four Cluster spacecraft are spin stabilized spacecraft which are designed and built under stringent requirements as far as electromagnetic cleanliness is concerned. Conductive surfaces and low electromagnetic background noise are mandatory for accurate electric field and cold plasma measurements. The mission is implemented in collaboration between ESA and NASA. A Russian mission will be closely coordinated with Cluster.

Lightweight Solar Photovoltaic Blankets

NASA Technical Reports Server (NTRS)

Ceragioli, R.; Himmler, R.; Nath, P.; Vogeli, C.; Guha, S.

1995-01-01

Lightweight, flexible sheets containing arrays of stacked solar photovoltaic cells developed to supply electric power aboard spacecraft. Solar batteries satisfying stringent requirements for operation in outer space also adaptable to terrestrial environment. Attractive for use as long-lived, portable photovoltaic power sources. Cells based on amorphous silicon which offers potential for order-of-magnitude increases in power per unit weight, power per unit volume, and endurance in presence of ionizing radiation.

DOE Zero Energy Ready Home Case Study: Palo Duro Homes — Palo Duro Homes, Albuquerque, NM

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

none,

2014-09-01

This builder was honored for Most DOE Zero Energy Ready Homes Built in the 2014 Housing Innovation Awards. By July 2014, Palo Duro had completed 152 homes since the program began in 2013 (under the original program title DOE Challenge Home), all of them certified to the stringent efficiency requirements of DOE’s Zero Energy Ready Home program.

Low Impact Development for Industrial Areas

DTIC Science & Technology

2015-07-01

Stormwater program managers are faced with increasingly stringent stormwater discharge limits for heavy metals such as copper, zinc , nutrients, total...limits for heavy metals such as copper, zinc , nutrients, total suspended solids (TSS), oil and grease. These limits are required to reduce...U.S. EPA), state agencies, and local agencies set permit limits as part of the total mass daily loading regulatory framework. Copper, zinc , lead

Conceptual design of the cryostat for the new high luminosity (HL-LHC) triplet magnets

NASA Astrophysics Data System (ADS)

Ramos, D.; Parma, V.; Moretti, M.; Eymin, C.; Todesco, E.; Van Weelderen, R.; Prin, H.; Berkowitz Zamora, D.

2017-12-01

The High Luminosity LHC (HL-LHC) is a project to upgrade the LHC collider after 2020-2025 to increase the integrated luminosity by about one order of magnitude and extend the physics production until 2035. An upgrade of the focusing triplets insertion system for the ATLAS and CMS experiments is foreseen using superconducting magnets operating in a pressurised superfluid helium bath at 1.9 K. This will require the design and construction of four continuous cryostats, each about sixty meters in length and one meter in diameter, for the final beam focusing quadrupoles, corrector magnets and beam separation dipoles. The design is constrained by the dimensions of the existing tunnel and accessibility restrictions imposing the integration of cryogenic piping inside the cryostat, thus resulting in a very compact integration. As the alignment and position stability of the magnets is crucial for the luminosity performance of the machine, the magnet support system must be carefully designed in order to cope with parasitic forces and thermo-mechanical load cycles. In this paper, we present the conceptual design of the cryostat and discuss the approach to address the stringent and often conflicting requirements of alignment, integration and thermal aspects.

Estimating the system price of redox flow batteries for grid storage

NASA Astrophysics Data System (ADS)

Ha, Seungbum; Gallagher, Kevin G.

2015-11-01

Low-cost energy storage systems are required to support extensive deployment of intermittent renewable energy on the electricity grid. Redox flow batteries have potential advantages to meet the stringent cost target for grid applications as compared to more traditional batteries based on an enclosed architecture. However, the manufacturing process and therefore potential high-volume production price of redox flow batteries is largely unquantified. We present a comprehensive assessment of a prospective production process for aqueous all vanadium flow battery and nonaqueous lithium polysulfide flow battery. The estimated investment and variable costs are translated to fixed expenses, profit, and warranty as a function of production volume. When compared to lithium-ion batteries, redox flow batteries are estimated to exhibit lower costs of manufacture, here calculated as the unit price less materials costs, owing to their simpler reactor (cell) design, lower required area, and thus simpler manufacturing process. Redox flow batteries are also projected to achieve the majority of manufacturing scale benefits at lower production volumes as compared to lithium-ion. However, this advantage is offset due to the dramatically lower present production volume of flow batteries compared to competitive technologies such as lithium-ion.

KSC Center Director Bridges addresses the audience at an ISO 9001 certification ceremony

NASA Technical Reports Server (NTRS)

1998-01-01

Center Director Roy Bridges speaks to KSC employees at the ISO certification ceremony held at the Training Auditorium. Bridges was presented an ISO 9001 certificate and plaque awarded to KSC by Det Norske Veritas (DNV), Inc., an international ISO certification organization. ISO 9001 comprises the most detailed, comprehensive set of standard requirements for quality programs established by the International Standards Organization. The presentation followed a successful independent audit by DNV of the KSC Management System in May of this year. The third-party auditors examined about 20 elements of KSC's system, including management responsibility, design control, documentation, test and inspection, and corrective action procedures. DNV found that KSC met or exceeded the stringent quality standards in all areas. KSC will use this certification as a tool to improve an already world- class team. All NASA centers are required by NASA Administrator Daniel S. Goldin to be ISO 9001 registered by September 1999. NASA is the first federal agency to seek the quality certification. Next to Bridges is Heidi Hollingsworth, with the Center for Independent Living, who uses American Sign Language for any hearing-impaired employees in the audience.

Ka-band monopulse antenna-pointing systems analysis and simulation

NASA Technical Reports Server (NTRS)

Lo, V. Y.

1996-01-01

NASA 's Deep Space Network (DSN) has been using both 70-m and 34-m reflector antennas to communicate with spacecraft at S-band (2.3 GHz) and X-band (8.45 GHz). To improve the quality of telecommunication and to meet future mission requirements, JPL has been developing 34-m Ka-band (32-GHz) beam waveguide antennas. Presently, antenna pointing operates in either the open-loop mode with blind pointing using navigation predicts or the closed-loop mode with conical scan (conscan). Pointing accuracy under normal conscan operating conditions is in the neighborhood of 5 mdeg. This is acceptable at S- and X-bands, but not enough at Ka-band. Due to the narrow beamwidth at Ka-band, it is important to improve pointing accuracy significantly (approximately 2 mdeg). Monopulse antenna tracking is one scheme being developed to meet the stringent pointing-accuracy requirement at Ka-band. Other advantages of monopulse tracking include low sensitivity to signal amplitude fluctuations as well as single-pulse processing for acquisition and tracking. This article presents system modeling, signal processing, simulation, and implementation of Ka-band monopulse tracking feed for antennas in NASA/DSN ground stations.

Multipurpose neutron generators based on the radio frequency quadrupole linear accelerator

NASA Astrophysics Data System (ADS)

Hamm, Robert W.

2000-12-01

Neutron generators based on the Radio Frequency Quadrupole accelerator are now used for a variety of applications. These compact linear accelerators can produce from 108 to more than 1013 neutrons/second using either proton or deuteron beams to bombard beryllium targets. They exhibit long lifetimes at full output, as there is little target or beam degradation. Since they do not use radioactive materials, licensing requirements are less stringent than for isotopic sources or tritium sealed tube generators. The light weight and compact size of these robust systems make them transportable. The low divergence output beam from the RFQ also allows use of a remote target, which can reduce the seize of the shielding and moderator. The RFQ linac can be designed with a wide range of output beam energy and used with other targets such as lithium and deuterium to produce a neutron spectrum tailored to a specific application. These pulsed systems are well-suited for applications requiring a high peak neutron flux, including activation analysis of very short-lived reaction products. They can replace conventional sources in non-destructive testing applications such as thermal or fast neutron radiography, and can also be used for cancer therapy.

Preliminary study of a millimeter wave FMCW InSAR for UAS indoor navigation.

PubMed

Scannapieco, Antonio F; Renga, Alfredo; Moccia, Antonio

2015-01-22

Small autonomous unmanned aerial systems (UAS) could be used for indoor inspection in emergency missions, such as damage assessment or the search for survivors in dangerous environments, e.g., power plants, underground railways, mines and industrial warehouses. Two basic functions are required to carry out these tasks, that is autonomous GPS-denied navigation with obstacle detection and high-resolution 3Dmapping with moving target detection. State-of-the-art sensors for UAS are very sensitive to environmental conditions and often fail in the case of poor visibility caused by dust, fog, smoke, flames or other factors that are met as nominal mission scenarios when operating indoors. This paper is a preliminary study concerning an innovative radar sensor based on the interferometric Synthetic Aperture Radar (SAR) principle, which has the potential to satisfy stringent requirements set by indoor autonomous operation. An architectural solution based on a frequency-modulated continuous wave (FMCW) scheme is proposed after a detailed analysis of existing compact and lightweight SAR. A preliminary system design is obtained, and the main imaging peculiarities of the novel sensor are discussed, demonstrating that high-resolution, high-quality observation of an assigned control volume can be achieved.

Preliminary Study of a Millimeter Wave FMCW InSAR for UAS Indoor Navigation

PubMed Central

Scannapieco, Antonio F.; Renga, Alfredo; Moccia, Antonio

2015-01-01

Small autonomous unmanned aerial systems (UAS) could be used for indoor inspection in emergency missions, such as damage assessment or the search for survivors in dangerous environments, e.g., power plants, underground railways, mines and industrial warehouses. Two basic functions are required to carry out these tasks, that is autonomous GPS-denied navigation with obstacle detection and high-resolution 3D mapping with moving target detection. State-of-the-art sensors for UAS are very sensitive to environmental conditions and often fail in the case of poor visibility caused by dust, fog, smoke, flames or other factors that are met as nominal mission scenarios when operating indoors. This paper is a preliminary study concerning an innovative radar sensor based on the interferometric Synthetic Aperture Radar (SAR) principle, which has the potential to satisfy stringent requirements set by indoor autonomous operation. An architectural solution based on a frequency-modulated continuous wave (FMCW) scheme is proposed after a detailed analysis of existing compact and lightweight SAR. A preliminary system design is obtained, and the main imaging peculiarities of the novel sensor are discussed, demonstrating that high-resolution, high-quality observation of an assigned control volume can be achieved. PMID:25621606

A two-qubit logic gate in silicon.

PubMed

Veldhorst, M; Yang, C H; Hwang, J C C; Huang, W; Dehollain, J P; Muhonen, J T; Simmons, S; Laucht, A; Hudson, F E; Itoh, K M; Morello, A; Dzurak, A S

2015-10-15

Quantum computation requires qubits that can be coupled in a scalable manner, together with universal and high-fidelity one- and two-qubit logic gates. Many physical realizations of qubits exist, including single photons, trapped ions, superconducting circuits, single defects or atoms in diamond and silicon, and semiconductor quantum dots, with single-qubit fidelities that exceed the stringent thresholds required for fault-tolerant quantum computing. Despite this, high-fidelity two-qubit gates in the solid state that can be manufactured using standard lithographic techniques have so far been limited to superconducting qubits, owing to the difficulties of coupling qubits and dephasing in semiconductor systems. Here we present a two-qubit logic gate, which uses single spins in isotopically enriched silicon and is realized by performing single- and two-qubit operations in a quantum dot system using the exchange interaction, as envisaged in the Loss-DiVincenzo proposal. We realize CNOT gates via controlled-phase operations combined with single-qubit operations. Direct gate-voltage control provides single-qubit addressability, together with a switchable exchange interaction that is used in the two-qubit controlled-phase gate. By independently reading out both qubits, we measure clear anticorrelations in the two-spin probabilities of the CNOT gate.

Multi-aperture microoptical system for close-up imaging

NASA Astrophysics Data System (ADS)

Berlich, René; Brückner, Andreas; Leitel, Robert; Oberdörster, Alexander; Wippermann, Frank; Bräuer, Andreas

2014-09-01

Modern applications in biomedical imaging, machine vision and security engineering require close-up optical systems with high resolution. Combined with the need for miniaturization and fast image acquisition of extended object fields, the design and fabrication of respective devices is extremely challenging. Standard commercial imaging solutions rely on bulky setups or depend on scanning techniques in order to meet the stringent requirements. Recently, our group has proposed a novel, multi-aperture approach based on parallel image transfer in order to overcome these constraints. It exploits state of the art microoptical manufacturing techniques on wafer level in order to create a compact, cost-effective system with a large field of view. However, initial prototypes have so far been subject to various limitations regarding their manufacturing, reliability and applicability. In this work, we demonstrate the optical design and fabrication of an advanced system, which overcomes these restrictions. In particular, a revised optical design facilitates a more efficient and economical fabrication process and inherently improves system reliability. An additional customized front side illumination module provides homogeneous white light illumination over the entire field of view while maintaining a high degree of compactness. Moreover, the complete imaging assembly is mounted on a positioning system. In combination with an extended working range, this allows for adjustment of the system's focus location. The final optical design is capable of capturing an object field of 36x24 mm2 with a resolution of 150 cycles/mm. Finally, we present experimental results of the respective prototype that demonstrate its enhanced capabilities.

Water reuse at highway rest areas : evaluation phase.

DOT National Transportation Integrated Search

1977-01-01

The limited availability of water and stringent wastewater effluent standards at rest areas led to the development of a water recycle-reuse system to treat flush water from water closets. Flush fluid for rest area water closets accounts for 95% to 97...

Trapped strontium ion optical clock

NASA Astrophysics Data System (ADS)

Barwood, G. P.; Gill, P.; Klein, H. A.; Hosaka, K.; Huang, G.; Lea, S. N.; Margolis, H. S.; Szymaniec, K.; Walton, B. R.

2017-11-01

Increasingly stringent demands on atomic timekeeping, driven by applications such as global navigation satellite systems (GNSS), communications, and very-long baseline interferometry (VBLI) radio astronomy, have motivated the development of improved time and frequency standards. There are many scientific applications of such devices in space.

Particulate matter emissions from combustion of wood in district heating applications

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

Ghafghazi, S.; Sowlati, T.; Sokhansanj, Shahabaddine

2011-01-01

The utilization of wood biomass to generate district heat and power in communities that have access to this energy source is increasing. In this paper the effect of wood fuel properties, combustion condition, and flue gas cleaning system on variation in the amount and formation of particles in the flue gas of typical district heating wood boilers are discussed based on the literature survey. Direct measurements of particulate matter (PM) emissions from wood boilers with district heating applications are reviewed and presented. Finally, recommendations are given regarding the selection of wood fuel, combustion system condition, and flue gas cleaning systemmore » in district heating systems in order to meet stringent air quality standards. It is concluded that utilization of high quality wood fuel, such as wood pellets produced from natural, uncontaminated stem wood, would generate the least PM emissions compared to other wood fuel types. Particulate matter emissions from grate burners equipped with electrostatic precipitators when using wood pellets can be well below stringent regulatory emission limit such as particulate emission limit of Metro Vancouver, Canada.« less

The Association of State Law to Physical Education Time Allocation in US Public Schools

PubMed Central

Oh, April; Chriqui, Jamie F.; Mâsse, Louise C.; Atienza, Audie A.; Nebeling, Linda; Agurs-Collins, Tanya; Moser, Richard P.; Dodd, Kevin W.

2012-01-01

Objectives. We examined whether public schools in states with specific and stringent physical education (PE) laws, as assessed by the Physical Education–Related State Policy Classification System (PERSPCS), available on the Classification of Laws Associated with School Students (C.L.A.S.S.) Web site, reported more weekly PE time in the most recent School Health Policies and Programs Survey (SHPPS). Methods. Schools (n = 410) were grouped by their state’s PERSPCS time requirement scores (none, nonspecific requirement, or specific requirement). Average weekly school-level PE was calculated using the SHPPS-reported PE minutes. Weighted analyses determined if PE minutes/week differed by PERSPCS group. Results. Schools in states with specific requirement laws averaged over 27 and 60 more PE minutes/week at the elementary and middle school levels, respectively, compared with schools within states with nonspecific laws and over 40 and 60 more PE minutes per week, respectively, compared with elementary and middle schools in states with no laws. High school results were nonsignificant. Conclusions. Public health guidelines recommend at least 60 minutes of daily physical activity for children, and PE may further this goal. Strong codified law with specific time requirements for PE may be an important tool contributing toward adequate PE time and daily physical activity recommendations. PMID:22594746

Registering medicines for low-income countries: how suitable are the stringent review procedures of the World Health Organisation, the US Food and Drug Administration and the European Medicines Agency?

PubMed

Doua, Joachim Y; Van Geertruyden, Jean-Pierre

2014-01-01

New medicines are registered after a resource-demanding process. Unfortunately, in low-income countries (LICs), demand outweighs resources. To facilitate registration in LICs, stringent review procedures of the European Medicines Agency (EMA Article-58), Food and Drug Administration (FDA PEPFAR-linked review) and WHO Prequalification programme have been established. Only the PEPFAR-linked review gives approval, while the others make recommendations for approval. This study assessed the performance and discussed the challenges of these three stringent review procedures. Data from WHO, FDA, EMA, Medline and Internet were analysed. Over 60% of medicines reviewed by stringent review procedures are manufactured in India. Until 2012, WHO prequalified 400 medicines (211 vaccines, 130 antiretrovirals, 29 tuberculostatics, 15 antimalarials and 15 others). PEPFAR-linked review approved 156 antiretrovirals, while EMA Article 58 recommended approval of 3 antiretrovirals, 1 vaccine and 1 antimalarial. WHO Prequalification and PEPFAR-linked review are free of charge and as a result have accelerated access to antiretrovirals. They both built capacity in sub-Saharan Africa, although WHO prequalification relies technically on stringent regulatory authorities and financially on donors. Article-58 offers the largest disease coverage and strongest technical capacities, is costly and involves fewer LICs. To meet the high demand for quality medicines in LICs, these stringent review procedures need to enlarge their disease coverage. To improve registration, EMA Article 58 should actively involve LICs. Furthermore, LIC regulatory activities must not be fully resigned to stringent review procedure. © 2013 John Wiley & Sons Ltd.

An alternative to sneakernet

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

Orrell, S.; Ralstin, S.

1992-04-01

Many computer security plans specify that only a small percentage of the data processed will be classified. Thus, the bulk of the data on secure systems must be unclassified. Secure limited access sites operating approved classified computing systems sometimes also have a system ostensibly containing only unclassified files but operating within the secure environment. That system could be networked or otherwise connected to a classified system(s) in order that both be able to use common resources for file storage or computing power. Such a system must operate under the same rules as the secure classified systems. It is in themore » nature of unclassified files that they either came from, or will eventually migrate to, a non-secure system. Today, unclassified files are exported from systems within the secure environment typically by loading transport media and carrying them to an open system. Import of unclassified files is handled similarly. This media transport process, sometimes referred to as sneaker net, often is manually logged and controlled only by administrative procedures. A comprehensive system for secure bi-directional transfer of unclassified files between secure and open environments has yet to be developed. Any such secure file transport system should be required to meet several stringent criteria. It is the purpose of this document to begin a definition of these criteria.« less

An alternative to sneakernet

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

Orrell, S.; Ralstin, S.

1992-01-01

Many computer security plans specify that only a small percentage of the data processed will be classified. Thus, the bulk of the data on secure systems must be unclassified. Secure limited access sites operating approved classified computing systems sometimes also have a system ostensibly containing only unclassified files but operating within the secure environment. That system could be networked or otherwise connected to a classified system(s) in order that both be able to use common resources for file storage or computing power. Such a system must operate under the same rules as the secure classified systems. It is in themore » nature of unclassified files that they either came from, or will eventually migrate to, a non-secure system. Today, unclassified files are exported from systems within the secure environment typically by loading transport media and carrying them to an open system. Import of unclassified files is handled similarly. This media transport process, sometimes referred to as sneaker net, often is manually logged and controlled only by administrative procedures. A comprehensive system for secure bi-directional transfer of unclassified files between secure and open environments has yet to be developed. Any such secure file transport system should be required to meet several stringent criteria. It is the purpose of this document to begin a definition of these criteria.« less

Commissioning of the vacuum system of the KATRIN Main Spectrometer

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

Arenz, M.; Babutzka, M.; Bahr, M.

The KATRIN experiment will probe the neutrino mass by measuring the β-electron energy spectrum near the endpoint of tritium β-decay. We performed an integral energy analysis by an electro-static spectrometer (``Main Spectrometer''), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m 3, and a complex inner electrode system with about 120 000 individual parts. The strong magnetic field that guides the β-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. Furthermore, a system consisting of 6 turbo-molecular pumps andmore » 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300 °C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10 -11 mbar range. We demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.« less

An ISVD-based Euclidian structure from motion for smartphones

NASA Astrophysics Data System (ADS)

Masiero, A.; Guarnieri, A.; Vettore, A.; Pirotti, F.

2014-06-01

The development of Mobile Mapping systems over the last decades allowed to quickly collect georeferenced spatial measurements by means of sensors mounted on mobile vehicles. Despite the large number of applications that can potentially take advantage of such systems, because of their cost their use is currently typically limited to certain specialized organizations, companies, and Universities. However, the recent worldwide diffusion of powerful mobile devices typically embedded with GPS, Inertial Navigation System (INS), and imaging sensors is enabling the development of small and compact mobile mapping systems. More specifically, this paper considers the development of a 3D reconstruction system based on photogrammetry methods for smartphones (or other similar mobile devices). The limited computational resources available in such systems and the users' request for real time reconstructions impose very stringent requirements on the computational burden of the 3D reconstruction procedure. This work takes advantage of certain recently developed mathematical tools (incremental singular value decomposition) and of photogrammetry techniques (structure from motion, Tomasi-Kanade factorization) to access very computationally efficient Euclidian 3D reconstruction of the scene. Furthermore, thanks to the presence of instrumentation for localization embedded in the device, the obtained 3D reconstruction can be properly georeferenced.

Commissioning of the vacuum system of the KATRIN Main Spectrometer

DOE PAGES

Arenz, M.; Babutzka, M.; Bahr, M.; ...

2016-04-07

The KATRIN experiment will probe the neutrino mass by measuring the β-electron energy spectrum near the endpoint of tritium β-decay. We performed an integral energy analysis by an electro-static spectrometer (``Main Spectrometer''), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m 3, and a complex inner electrode system with about 120 000 individual parts. The strong magnetic field that guides the β-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. Furthermore, a system consisting of 6 turbo-molecular pumps andmore » 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300 °C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10 -11 mbar range. We demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.« less

Optical interconnection networks for high-performance computing systems

NASA Astrophysics Data System (ADS)

Biberman, Aleksandr; Bergman, Keren

2012-04-01

Enabled by silicon photonic technology, optical interconnection networks have the potential to be a key disruptive technology in computing and communication industries. The enduring pursuit of performance gains in computing, combined with stringent power constraints, has fostered the ever-growing computational parallelism associated with chip multiprocessors, memory systems, high-performance computing systems and data centers. Sustaining these parallelism growths introduces unique challenges for on- and off-chip communications, shifting the focus toward novel and fundamentally different communication approaches. Chip-scale photonic interconnection networks, enabled by high-performance silicon photonic devices, offer unprecedented bandwidth scalability with reduced power consumption. We demonstrate that the silicon photonic platforms have already produced all the high-performance photonic devices required to realize these types of networks. Through extensive empirical characterization in much of our work, we demonstrate such feasibility of waveguides, modulators, switches and photodetectors. We also demonstrate systems that simultaneously combine many functionalities to achieve more complex building blocks. We propose novel silicon photonic devices, subsystems, network topologies and architectures to enable unprecedented performance of these photonic interconnection networks. Furthermore, the advantages of photonic interconnection networks extend far beyond the chip, offering advanced communication environments for memory systems, high-performance computing systems, and data centers.

It Security and EO Systems

NASA Astrophysics Data System (ADS)

Burnett, M.

2010-12-01

One topic that is beginning to influence the systems that support these goals is that of Information Technology (IT) Security. Unsecure systems are vulnerable to increasing attacks and other negative consequences; sponsoring agencies are correspondingly responding with more refined policies and more stringent security requirements. These affect how EO systems can meet the goals of data and service interoperability and harmonization through open access, transformation and visualization services. Contemporary systems, including the vision of a system-of-systems (such as GEOSS, the Global Earth Observation System of Systems), utilize technologies that support a distributed, global, net-centric environment. These types of systems have a high reliance on the open systems, web services, shared infrastructure and data standards. The broader IT industry has developed and used these technologies in their business and mission critical systems for many years. Unfortunately, the IT industry, and their customers have learned the importance of protecting their assets and resources (computing and information) as they have been forced to respond to an ever increasing number and more complex illegitimate “attackers”. This presentation will offer an overview of work done by the CEOS WGISS organization in summarizing security threats, the challenges to responding to them and capturing the current state of the practice within the EO community.

Digital orthoimagery base specification V1.0

USGS Publications Warehouse

Rufe, Philip P.

2014-01-01

The resolution requirement for orthoimagery in support of the The National Map of the U.S. Geological Survey (USGS) is 1 meter. However, as the Office of Management and Budget A-16 designated Federal agency responsible for base orthoimagery, the USGS National Geospatial Program (NGP) has developed this base specification to include higher resolution orthoimagery. Many Federal, State, and local programs use high-resolution orthoimagery for various purposes including critical infrastructure management, vector data updates, land-use analysis, natural resource inventory, and extraction of data. The complex nature of large-area orthoimagery datasets, combined with the broad interest in orthoimagery, which is of consistent quality and spatial accuracy, requires high-resolution orthoimagery to meet or exceed the format and content outlined in this specification. The USGS intends to use this specification primarily to create consistency across all NGP funded and managed orthoimagery collections, in particular, collections in support of the National Digital Orthoimagery Program (NDOP). In the absence of other comprehensive specifications or standards, the USGS intends that this specification will, to the highest degree practical, be adopted by other USGS programs and mission areas, and by other Federal agencies. This base specification, defining minimum parameters for orthoimagery data collection. Local conditions in any given project area, specialized applications for the data, or the preferences of cooperators, may mandate more stringent requirements. The USGS fully supports the acquisition of more detailed, accurate, or value-added data that exceed the base specification outlined herein. A partial list of common “buy-up” options is provided in appendix 1 for those areas and projects that require more stringent or expanded specifications.

Polysilicon planarization and plug recess etching in a decoupled plasma source chamber using two endpoint techniques

NASA Astrophysics Data System (ADS)

Kaplita, George A.; Schmitz, Stefan; Ranade, Rajiv; Mathad, Gangadhara S.

1999-09-01

The planarization and recessing of polysilicon to form a plug are processes of increasing importance in silicon IC fabrication. While this technology has been developed and applied to DRAM technology using Trench Storage Capacitors, the need for such processes in other IC applications (i.e. polysilicon studs) has increased. Both planarization and recess processes usually have stringent requirements on etch rate, recess uniformity, and selectivity to underlying films. Additionally, both processes generally must be isotropic, yet must not expand any seams that might be present in the polysilicon fill. These processes should also be insensitive to changes in exposed silicon area (pattern factor) on the wafer. A SF6 plasma process in a polysilicon DPS (Decoupled Plasma Source) reactor has demonstrated the capability of achieving the above process requirements for both planarization and recess etch. The SF6 process in the decoupled plasma source reactor exhibited less sensitivity to pattern factor than in other types of reactors. Control of these planarization and recess processes requires two endpoint systems to work sequentially in the same recipe: one for monitoring the endpoint when blanket polysilicon (100% Si loading) is being planarized and one for monitoring the recess depth while the plug is being recessed (less than 10% Si loading). The planarization process employs an optical emission endpoint system (OES). An interferometric endpoint system (IEP), capable of monitoring lateral interference, is used for determining the recess depth. The ability of using either or both systems is required to make these plug processes manufacturable. Measuring the recess depth resulting from the recess process can be difficult, costly and time- consuming. An Atomic Force Microscope (AFM) can greatly alleviate these problems and can serve as a critical tool in the development of recess processes.

A comparison of five methods for monitoring the precision of automated x-ray film processors.

PubMed

Nickoloff, E L; Leo, F; Reese, M

1978-11-01

Five different methods for preparing sensitometric strips used to monitor the precision of automated film processors are compared. A method for determining the sensitivity of each system to processor variations is presented; the observed statistical variability is multiplied by the system response to temperature or chemical changes. Pre-exposed sensitometric strips required the use of accurate densitometers and stringent control limits to be effective. X-ray exposed sensitometric strips demonstrated large variations in the x-ray output (2 omega approximately equal to 8.0%) over a period of one month. Some light sensitometers were capable of detecting +/- 1.0 degrees F (+/- 0.6 degrees C) variations in developer temperature in the processor and/or about 10.0 ml of chemical contamination in the processor. Nevertheless, even the light sensitometers were susceptible to problems, e.g. film emulsion selection, line voltage variations, and latent image fading. Advantages and disadvantages of the various sensitometric methods are discussed.

Performance improvements of binary diffractive structures via optimization of the photolithography and dry etch processes

NASA Astrophysics Data System (ADS)

Welch, Kevin; Leonard, Jerry; Jones, Richard D.

2010-08-01

Increasingly stringent requirements on the performance of diffractive optical elements (DOEs) used in wafer scanner illumination systems are driving continuous improvements in their associated manufacturing processes. Specifically, these processes are designed to improve the output pattern uniformity of off-axis illumination systems to minimize degradation in the ultimate imaging performance of a lithographic tool. In this paper, we discuss performance improvements in both photolithographic patterning and RIE etching of fused silica diffractive optical structures. In summary, optimized photolithographic processes were developed to increase critical dimension uniformity and featuresize linearity across the substrate. The photoresist film thickness was also optimized for integration with an improved etch process. This etch process was itself optimized for pattern transfer fidelity, sidewall profile (wall angle, trench bottom flatness), and across-wafer etch depth uniformity. Improvements observed with these processes on idealized test structures (for ease of analysis) led to their implementation in product flows, with comparable increases in performance and yield on customer designs.

SWIFT BAT Loop Heat Pipe Thermal System Characteristics and Ground/Flight Operation Procedure

NASA Technical Reports Server (NTRS)

Choi, Michael K.

2003-01-01

The SWIFT Burst Alert Telescope (BAT) Detector Array has a total power dissipation of 208 W. To meet the stringent temperature gradient and thermal stability requirements in the normal operational mode, and heater power budget in both the normal operational and safehold modes, the Detector Array is thermally well coupled to eight constant conductance heat pipes (CCHPs) embedded in the Detector Array Plate (DAP), and two loop heat pipes (LHPs) transport heat fiom the CCHPs to a radiator. The CCHPs have ammonia as the working fluid and the LHPs have propylene as the working fluid. Precision heater controllers, which have adjustable set points in flight, are used to control the LHP compensation chamber and Detector Array XA1 ASIC temperatures. The radiator has the AZ-Tek AZW-LA-II low-alpha white paint as the thermal coating and is located on the anti-sun side of the spacecraft. This paper presents the characteristics, ground operation and flight operation procedures of the LHP thermal system.

Electro-Mechanical Simulation of a Large Aperture MOEMS Fabry-Perot Tunable Filter

NASA Technical Reports Server (NTRS)

Kuhn, Jonathan L.; Barclay, Richard B.; Greenhouse, Matthew A.; Mott, D. Brent; Satyapal, Shobita; Powers, Edward I. (Technical Monitor)

2000-01-01

We are developing a micro-machined electrostatically actuated Fabry-Perot tunable filter with a large clear aperture for application in high through-put wide-field imaging spectroscopy and lidar systems. In the first phase of this effort, we are developing key components based on coupled electro-mechanical simulations. In particular, the movable etalon plate design leverages high coating stresses to yield a flat surface in drum-head tension over a large diameter (12.5 mm). In this approach, the cylindrical silicon movable plate is back etched, resulting in an optically coated membrane that is suspended from a thick silicon support ring. Understanding the interaction between the support ring, suspended membrane, and coating is critical to developing surfaces that are flat to within stringent etalon requirements. In this work, we present the simulations used to develop the movable plate, spring suspension system, and electrostatic actuation mechanism. We also present results from tests of fabricated proof of concept components.

High-Heat-Flux Cyclic Durability of Thermal and Environmental Barrier Coatings

NASA Technical Reports Server (NTRS)

Zhu, Dongming; Ghosn, Louis L.; Miller, Robert A.

2007-01-01

Advanced ceramic thermal and environmental barrier coatings will play an increasingly important role in future gas turbine engines because of their ability to protect the engine components and further raise engine temperatures. For the supersonic vehicles currently envisioned in the NASA fundamental aeronautics program, advanced gas turbine engines will be used to provide high power density thrust during the extended supersonic flight of the aircraft, while meeting stringent low emission requirements. Advanced ceramic coating systems are critical to the performance, life and durability of the hot-section components of the engine systems. In this work, the laser and burner rig based high-heat-flux testing approaches were developed to investigate the coating cyclic response and failure mechanisms under simulated supersonic long-duration cruise mission. The accelerated coating cracking and delamination mechanism under the engine high-heat-flux, and extended supersonic cruise time conditions will be addressed. A coating life prediction framework may be realized by examining the crack initiation and propagation in conjunction with environmental degradation under high-heat-flux test conditions.

NASA's Space Launch System: An Evolving Capability for Exploration

NASA Technical Reports Server (NTRS)

Creech, Stephen D.; Robinson, Kimberly F.

2016-01-01

Designed to meet the stringent requirements of human exploration missions into deep space and to Mars, NASA's Space Launch System (SLS) vehicle represents a unique new launch capability opening new opportunities for mission design. NASA is working to identify new ways to use SLS to enable new missions or mission profiles. In its initial Block 1 configuration, capable of launching 70 metric tons (t) to low Earth orbit (LEO), SLS is capable of not only propelling the Orion crew vehicle into cislunar space, but also delivering small satellites to deep space destinations. The evolved configurations of SLS, including both the 105 t Block 1B and the 130 t Block 2, offer opportunities for launching co-manifested payloads and a new class of secondary payloads with the Orion crew vehicle, and also offer the capability to carry 8.4- or 10-m payload fairings, larger than any contemporary launch vehicle, delivering unmatched mass-lift capability, payload volume, and C3.

Reverse phase protein microarrays: fluorometric and colorimetric detection.

PubMed

Gallagher, Rosa I; Silvestri, Alessandra; Petricoin, Emanuel F; Liotta, Lance A; Espina, Virginia

2011-01-01

The Reverse Phase Protein Microarray (RPMA) is an array platform used to quantitate proteins and their posttranslationally modified forms. RPMAs are applicable for profiling key cellular signaling pathways and protein networks, allowing direct comparison of the activation state of proteins from multiple samples within the same array. The RPMA format consists of proteins immobilized directly on a nitrocellulose substratum. The analyte is subsequently probed with a primary antibody and a series of reagents for signal amplification and detection. Due to the diversity, low concentration, and large dynamic range of protein analytes, RPMAs require stringent signal amplification methods, high quality image acquisition, and software capable of precisely analyzing spot intensities on an array. Microarray detection strategies can be either fluorescent or colorimetric. The choice of a detection system depends on (a) the expected analyte concentration, (b) type of microarray imaging system, and (c) type of sample. The focus of this chapter is to describe RPMA detection and imaging using fluorescent and colorimetric (diaminobenzidine (DAB)) methods.

Thermal Protection for Mars Sample Return Earth Entry Vehicle: A Grand Challenge for Design Methodology and Reliability Verification

NASA Technical Reports Server (NTRS)

Venkatapathy, Ethiraj; Gage, Peter; Wright, Michael J.

2017-01-01

Mars Sample Return is our Grand Challenge for the coming decade. TPS (Thermal Protection System) nominal performance is not the key challenge. The main difficulty for designers is the need to verify unprecedented reliability for the entry system: current guidelines for prevention of backward contamination require that the probability of spores larger than 1 micron diameter escaping into the Earth environment be lower than 1 million for the entire system, and the allocation to TPS would be more stringent than that. For reference, the reliability allocation for Orion TPS is closer to 11000, and the demonstrated reliability for previous human Earth return systems was closer to 1100. Improving reliability by more than 3 orders of magnitude is a grand challenge indeed. The TPS community must embrace the possibility of new architectures that are focused on reliability above thermal performance and mass efficiency. MSR (Mars Sample Return) EEV (Earth Entry Vehicle) will be hit with MMOD (Micrometeoroid and Orbital Debris) prior to reentry. A chute-less aero-shell design which allows for self-righting shape was baselined in prior MSR studies, with the assumption that a passive system will maximize EEV robustness. Hence the aero-shell along with the TPS has to take ground impact and not break apart. System verification will require testing to establish ablative performance and thermal failure but also testing of damage from MMOD, and structural performance at ground impact. Mission requirements will demand analysis, testing and verification that are focused on establishing reliability of the design. In this proposed talk, we will focus on the grand challenge of MSR EEV TPS and the need for innovative approaches to address challenges in modeling, testing, manufacturing and verification.

Automated telescope scheduling

NASA Technical Reports Server (NTRS)

Johnston, Mark D.

1988-01-01

With the ever increasing level of automation of astronomical telescopes the benefits and feasibility of automated planning and scheduling are becoming more apparent. Improved efficiency and increased overall telescope utilization are the most obvious goals. Automated scheduling at some level has been done for several satellite observatories, but the requirements on these systems were much less stringent than on modern ground or satellite observatories. The scheduling problem is particularly acute for Hubble Space Telescope: virtually all observations must be planned in excruciating detail weeks to months in advance. Space Telescope Science Institute has recently made significant progress on the scheduling problem by exploiting state-of-the-art artificial intelligence software technology. What is especially interesting is that this effort has already yielded software that is well suited to scheduling groundbased telescopes, including the problem of optimizing the coordinated scheduling of more than one telescope.

A Proteomic Workflow Using High-Throughput De Novo Sequencing Towards Complementation of Genome Information for Improved Comparative Crop Science.

PubMed

Turetschek, Reinhard; Lyon, David; Desalegn, Getinet; Kaul, Hans-Peter; Wienkoop, Stefanie

2016-01-01

The proteomic study of non-model organisms, such as many crop plants, is challenging due to the lack of comprehensive genome information. Changing environmental conditions require the study and selection of adapted cultivars. Mutations, inherent to cultivars, hamper protein identification and thus considerably complicate the qualitative and quantitative comparison in large-scale systems biology approaches. With this workflow, cultivar-specific mutations are detected from high-throughput comparative MS analyses, by extracting sequence polymorphisms with de novo sequencing. Stringent criteria are suggested to filter for confidential mutations. Subsequently, these polymorphisms complement the initially used database, which is ready to use with any preferred database search algorithm. In our example, we thereby identified 26 specific mutations in two cultivars of Pisum sativum and achieved an increased number (17 %) of peptide spectrum matches.

Spectral analysis for GNSS coordinate time series using chirp Fourier transform

NASA Astrophysics Data System (ADS)

Feng, Shengtao; Bo, Wanju; Ma, Qingzun; Wang, Zifan

2017-12-01

Spectral analysis for global navigation satellite system (GNSS) coordinate time series provides a principal tool to understand the intrinsic mechanism that affects tectonic movements. Spectral analysis methods such as the fast Fourier transform, Lomb-Scargle spectrum, evolutionary power spectrum, wavelet power spectrum, etc. are used to find periodic characteristics in time series. Among spectral analysis methods, the chirp Fourier transform (CFT) with less stringent requirements is tested with synthetic and actual GNSS coordinate time series, which proves the accuracy and efficiency of the method. With the length of series only limited to even numbers, CFT provides a convenient tool for windowed spectral analysis. The results of ideal synthetic data prove CFT accurate and efficient, while the results of actual data show that CFT is usable to derive periodic information from GNSS coordinate time series.

Welfare reform: advocacy and intervention in the health care setting.

PubMed Central

Lawton, E; Leiter, K; Todd, J; Smith, L

1999-01-01

Welfare reform has drastically altered the lives of poor families in the US. In its wake, many former recipients are not receiving whatever transitional benefits and other safeguards to which they remain entitled under federal and state laws. Families are losing access to Medicaid and are not receiving the child care assistance or Food Stamps for which they continue to be eligible. Ill-served by stringent time limits and work requirements, lack of child care assistance, and lack of training and educational opportunities for the development of skills that will lead to better jobs, families need help to navigate the complexities of the new welfare system. Boston Medical Center's Department of Pediatrics has instituted a welfare screening project to educate families about their rights under welfare reform and assist them in advocating for themselves and their children. PMID:10670622

Enhancing the Bandwidth of Gravitational-Wave Detectors with Unstable Optomechanical Filters

NASA Astrophysics Data System (ADS)

Miao, Haixing; Ma, Yiqiu; Zhao, Chunnong; Chen, Yanbei

2015-11-01

Advanced interferometric gravitational-wave detectors use optical cavities to resonantly enhance their shot-noise-limited sensitivity. Because of positive dispersion of these cavities—signals at different frequencies pick up different phases, there is a tradeoff between the detector bandwidth and peak sensitivity, which is a universal feature for quantum measurement devices having resonant cavities. We consider embedding an active unstable filter inside the interferometer to compensate the phase, and using feedback control to stabilize the entire system. We show that this scheme in principle can enhance the bandwidth without sacrificing the peak sensitivity. However, the unstable filter under our current consideration is a cavity-assisted optomechanical device operating in the instability regime, and the thermal fluctuation of the mechanical oscillator puts a very stringent requirement on the environmental temperature and the mechanical quality factor.

Achieving Vibration Stability of the NSLS-II Hard X-ray Nanoprobe Beamline

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

Simos, N.; Chu, Y. N.; Broadbent, A.

2010-08-30

The Hard X-ray Nanoprobe (HXN) Beamline of National Synchrotron Light Source II (NSLS-lI) requires high levels of stability in order to achieve the desired instrument resolution. To ensure that the design of the endstation helps meet the stringent criteria and that natural and cultural vibration is mitigated both passively and actively, a comprehensive study complimentary to the design process has been undertaken. Vibration sources that have the potential to disrupt sensitive experiments such as wind, traffic and NSLS II operating systems have been studied using state of the art simulations and an array of field data. Further, final stage vibrationmore » isolation principles have been explored in order to be utilized in supporting endstation instruments. This paper presents results of the various study aspects and their influence on the HXN design optimization.« less

Optimization of an organic memristor as an adaptive memory element

NASA Astrophysics Data System (ADS)

Berzina, Tatiana; Smerieri, Anteo; Bernabò, Marco; Pucci, Andrea; Ruggeri, Giacomo; Erokhin, Victor; Fontana, M. P.

2009-06-01

The combination of memory and signal handling characteristics of a memristor makes it a promising candidate for adaptive bioinspired information processing systems. This poses stringent requirements on the basic device, such as stability and reproducibility over a large number of training/learning cycles, and a large anisotropy in the fundamental control material parameter, in our case the electrical conductivity. In this work we report results on the improved performance of electrochemically controlled polymeric memristors, where optimization of a conducting polymer (polyaniline) in the active channel and better environmental control of fabrication methods led to a large increase both in the absolute values of the conductivity in the partially oxydized state of polyaniline and of the on-off conductivity ratio. These improvements are crucial for the application of the organic memristor to adaptive complex signal handling networks.

A combined Earth scanner and momentum wheel for attitude determination and control of small spacecraft

NASA Astrophysics Data System (ADS)

Bialke, Bill

1992-05-01

In order to satisfy the stringent cost and power requirements of small satellites, an advanced SCANWHEEL was designed, built, and qualified by ITHACO, Inc. The T-SCANWHEEL is a modular momentum/reaction wheel with an integral conical Earth scanner. The momentum wheel provides momentum bias and control torques about the pitch axis of a spacecraft. An angled scan mirror coupled to the rotating shaft of the momentum wheel provides a conical scan of the field-of-view of an infrared sensor to provide pitch-and-roll attitude information. By using the same motor and bearings for the momentum wheel and Earth scanner, the overall power consumption is reduced and the system reliability is enhanced. The evolution of the T-SCANWHEEL is presented, including design ground rules, tradeoff analyses, and performance results.

Structural integrity and containment aspects of small gas turbine engines

NASA Astrophysics Data System (ADS)

Gupta, S. S.; Gomuc, R.

1994-03-01

Structural integrity of rotating components in gas turbine engines is very crucial since their failure implies high impact energy, which, if uncontained, could mean damage to aircraft structures, controls, and so forth, and, in the worst scenario, even loss of lives. This final consequence has led to very stringent airworthiness regulations for engine/aircraft certifications. This paper discusses the historical statistics of noncontainment events in turbofans, turboprops, and turboshafts and shows how the damage severity varies between different applications and how changes to regulations are continuing in order to improve the reliability of aircraft/rotorcraft. The paper also presents design challenges resulting from the analysis complexity of containment/noncontainment event and the way Pratt & Whitney Canada design/analysis/test system caters to all the requirements. The weight and cost impact of possible changes to current regulations are also presented.

Vision Technology for Automated Inspection of Hybrid Microelectronics Assemblies

DTIC Science & Technology

1988-06-01

circuits are a very efficient packaging technique, with the primary advantages of size, better resistance to environ - 0 ments, and the flexibility to...produced for the military are much more complex and have more stringent performance requirements, particularly in their resistance to environments and...boards, particularly because of the need to protect circuits from a hostile environment such as salt, heat, and moisture. Included among the major U.S

Development of hermetic electrical connectors for SSC spool pieces

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

Kountanis, B.; Kalny, L.

1993-05-01

The Superconducting Super Collider ring is about 54 miles (87 km circumference) and primarily includes a series of magnets. Spool piece assemblies are interspaced in the ring at predetermined intervals to provide specific functions such as cryogenic interfaces, vacuum interface, magnet power, magnet power dump, quench heater power, and special instrumentation. Electrical connectors serve as interfaces for instrumentation and quench heater circuits. These connectors have to meet stringent requirements.

Applications of Probabilistic Combiners on Linear Feedback Shift Register Sequences

DTIC Science & Technology

2016-12-01

on the resulting output strings show a drastic increase in complexity, while simultaneously passing the stringent randomness tests required by the...a three-variable function. Our tests on the resulting output strings show a drastic increase in complex- ity, while simultaneously passing the...10001101 01000010 11101001 Decryption of a message that has been encrypted using bitwise XOR is quite simple. Since each bit is its own additive inverse

The evolution and challenges for the international harmonization of the regulation of pharmaceutical excipients in Taiwan.

PubMed

Chang, Lin-Chau; Kang, Jaw-Jou; Gau, Churn-Shiouh

2015-12-01

Excipients, once considered an inert component, have been shown to greatly influence the characteristics of the drug product, such as quality and safety. Functionality-related characteristics of excipients could affect the performance of the drug product. Moreover, the impact of globalization has complicated the issue and made the supervision of supply chain highly important. Taiwan, a member of the Pharmaceutical Inspection Convention and Pharmaceutical Inspection Co-operation Scheme, makes efforts to harmonize with international regulations and to strengthen the protection of patients through regulatory controls. In order to improve the harmonization and the transparency of regulatory requirements, the aim of the present study was to investigate the regulatory framework and considerations of stringent regulatory authorities and to propose the draft regulatory requirements to the Taiwan Food and Drug Administration for jurisdiction. The proposal which was extensively discussed in the expert committee includes the regulatory considerations to ensure the safety and quality of the excipients and may serve as a platform to facilitate the communication with industries about the current thinking on related issues. Moreover, through the review of the recent guidelines published by the stringent regulatory authorities, the trend of the regulatory considerations was revealed and discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

Feedback System Theory

DTIC Science & Technology

1978-11-01

R 2. GOVT A $ SION NO. 3 RIEqLPýIVT’S.;TALOG NUMBER r/ 4. TITLE (and wbiFflT, -L M4 1 , FEEDBACK SYSTEM THEORY ~r Inter in- 6. PERFORMING ORG. REPORT...ANNUAL REPORT FEEDBACK SYSTEM THEORY AFOSR GRANT NO. 76-2946B Air Force Office of Scientific Research for year ending October 31, 1978 79 02 08 L|I...re less stringent than in other synthesis techniques which cannot handle significant parameter uncertainty. _I FEEDBACK SYSTEM THEORY 1. Introduction

Piloted simulator study of allowable time delay in pitch flight control system of a transport airplane with negative static stability

NASA Technical Reports Server (NTRS)

Grantham, William D.; Smith, Paul M.; Person, Lee H., Jr.; Meyer, Robert T.; Tingas, Stephen A.

1987-01-01

A piloted simulation study was conducted to determine the permissible time delay in the flight control system of a 10-percent statically unstable transport airplane during cruise flight conditions. The math model used for the simulation was a derivative Lockheed L-1011 wide-body jet transport. Data were collected and analyzed from a total of 137 cruising flights in both calm- and turbulent-air conditions. Results of this piloted simulation study verify previous findings that show present military specifications for allowable control-system time delay may be too stringent when applied to transport-size airplanes. Also, the degree of handling-qualities degradation due to time delay is shown to be strongly dependent on the source of the time delay in an advanced flight control system. Maximum allowable time delay for each source of time delay in the control system, in addition to a less stringent overall maximum level of time delay, should be considered for large aircraft. Preliminary results also suggest that adverse effects of control-system time delay may be at least partially offset by variations in control gearing. It is recommended that the data base include different airplane baselines, control systems, and piloting tasks with many pilots participating, so that a reasonable set of limits for control-system time delay can be established to replace the military specification limits currently being used.

GPS navigation algorithms for Autonomous Airborne Refueling of Unmanned Air Vehicles

NASA Astrophysics Data System (ADS)

Khanafseh, Samer Mahmoud

Unmanned Air Vehicles (UAVs) have recently generated great interest because of their potential to perform hazardous missions without risking loss of life. If autonomous airborne refueling is possible for UAVs, mission range and endurance will be greatly enhanced. However, concerns about UAV-tanker proximity, dynamic mobility and safety demand that the relative navigation system meets stringent requirements on accuracy, integrity, and continuity. In response, this research focuses on developing high-performance GPS-based navigation architectures for Autonomous Airborne Refueling (AAR) of UAVs. The AAR mission is unique because of the potentially severe sky blockage introduced by the tanker. To address this issue, a high-fidelity dynamic sky blockage model was developed and experimentally validated. In addition, robust carrier phase differential GPS navigation algorithms were derived, including a new method for high-integrity reacquisition of carrier cycle ambiguities for recently-blocked satellites. In order to evaluate navigation performance, world-wide global availability and sensitivity covariance analyses were conducted. The new navigation algorithms were shown to be sufficient for turn-free scenarios, but improvement in performance was necessary to meet the difficult requirements for a general refueling mission with banked turns. Therefore, several innovative methods were pursued to enhance navigation performance. First, a new theoretical approach was developed to quantify the position-domain integrity risk in cycle ambiguity resolution problems. A mechanism to implement this method with partially-fixed cycle ambiguity vectors was derived, and it was used to define tight upper bounds on AAR navigation integrity risk. A second method, where a new algorithm for optimal fusion of measurements from multiple antennas was developed, was used to improve satellite coverage in poor visibility environments such as in AAR. Finally, methods for using data-link extracted measurements as an additional inter-vehicle ranging measurement were also introduced. The algorithms and methods developed in this work are generally applicable to realize high-performance GPS-based navigation in partially obstructed environments. Navigation performance for AAR was quantified through covariance analysis, and it was shown that the stringent navigation requirements for this application are achievable. Finally, a real-time implementation of the algorithms was developed and successfully validated in autopiloted flight tests.

The Stringent Response Is Essential for Pseudomonas aeruginosa Virulence in the Rat Lung Agar Bead and Drosophila melanogaster Feeding Models of Infection▿†

PubMed Central

Vogt, Stefanie L.; Green, Christopher; Stevens, Katarzyna M.; Day, Brad; Erickson, David L.; Woods, Donald E.; Storey, Douglas G.

2011-01-01

The stringent response is a regulatory system that allows bacteria to sense and adapt to nutrient-poor environments. The central mediator of the stringent response is the molecule guanosine 3′,5′-bispyrophosphate (ppGpp), which is synthesized by the enzymes RelA and SpoT and which is also degraded by SpoT. Our laboratory previously demonstrated that a relA mutant of Pseudomonas aeruginosa, the principal cause of lung infections in cystic fibrosis patients, was attenuated in virulence in a Drosophila melanogaster feeding model of infection. In this study, we examined the role of spoT in P. aeruginosa virulence. We generated an insertion mutation in spoT within the previously constructed relA mutant, thereby producing a ppGpp-devoid strain. The relA spoT double mutant was unable to establish a chronic infection in D. melanogaster and was also avirulent in the rat lung agar bead model of infection, a model in which the relA mutant is fully virulent. Synthesis of the virulence determinants pyocyanin, elastase, protease, and siderophores was impaired in the relA spoT double mutant. This mutant was also defective in swarming and twitching, but not in swimming motility. The relA spoT mutant and, to a lesser extent, the relA mutant were less able to withstand stresses such as heat shock and oxidative stress than the wild-type strain PAO1, which may partially account for the inability of the relA spoT mutant to successfully colonize the rat lung. Our results indicate that the stringent response, and SpoT in particular, is a crucial regulator of virulence processes in P. aeruginosa. PMID:21788391

Mercury emission trend influenced by stringent air pollutants regulation for coal-fired power plants in Korea

NASA Astrophysics Data System (ADS)

Pudasainee, Deepak; Kim, Jeong-Hun; Seo, Yong-Chil

2009-12-01

Regulatory control of mercury emission from anthropogenic sources has become a global concern in the recent past. Coal-fired power plants are one of the largest sources of anthropogenic mercury emission into the atmosphere. This paper summarizes the current reducing trend of mercury emission as co-beneficial effect by more stringent regulation changes to control primary air pollutants with introducing test results from the commercial coal-fired facilities and suggesting a guideline for future regulatory development in Korea. On average, mercury emission concentrations ranged 16.3-2.7 μg Sm -3, 2.4-1.1 μg Sm -3, 3.1-0.7 μg Sm -3 from anthracite coal-fired power plants equipped with electrostatic precipitator (ESP), bituminous coal-fired power plants with ESP + flue gas desulphurization (FGD) and bituminous coal-fired power plants with selective catalytic reactor (SCR) + cold side (CS) - ESP + wet FGD, respectively. Among the existing air pollution control devices, the best configuration for mercury removal in coal-fired power plants was SCR + CS - ESP + wet FGD, which were installed due to the stringent regulation changes to control primary air pollutants emission such as SO 2, NOx and dust. It was estimated that uncontrolled and controlled mercury emission from coal-fired power plants as 10.3 ton yr -1 and 3.2 ton yr -1 respectively. After the installation of ESP, FGD and SCR system, following the enforcement of the stringent regulation, 7.1 ton yr -1 of mercury emission has been reduced (nearly 69%) from coal-fired power plants as a co-benefit control. Based on the overall study, a sample guideline including emission limits were suggested which will be applied to develop a countermeasure for controlling mercury emission from coal-fired power plants.

Performance of two updated blood glucose monitoring systems: an evaluation following ISO 15197:2013.

PubMed

Pleus, Stefan; Baumstark, Annette; Rittmeyer, Delia; Jendrike, Nina; Haug, Cornelia; Freckmann, Guido

2016-05-01

Objective For patients with diabetes, regular self-monitoring of blood glucose (SMBG) is essential to ensure adequate glycemic control. Therefore, accurate and reliable blood glucose measurements with SMBG systems are necessary. The international standard ISO 15197 describes requirements for SMBG systems, such as limits within which 95% of glucose results have to fall to reach acceptable system accuracy. The 2013 version of this standard sets higher demands, especially regarding system accuracy, than the currently still valid edition. ISO 15197 can be applied by manufacturers to receive a CE mark for their system. Research design and methods This study was an accuracy evaluation following ISO 15197:2013 section 6.3 of two recently updated SMBG systems (Contour * and Contour TS; Bayer Consumer Care AG, Basel, Switzerland) with an improved algorithm to investigate whether the systems fulfill the requirements of the new standard. For this purpose, capillary blood samples of approximately 100 participants were measured with three test strip lots of both systems and deviations from glucose values obtained with a hexokinase-based comparison method (Cobas Integra † 400 plus; Roche Instrument Center, Rotkreuz, Switzerland) were determined. Percentages of values within the acceptance criteria of ISO 15197:2013 were calculated. This study was registered at clinicaltrials.gov (NCT02358408). Main outcome Both updated systems fulfilled the system accuracy requirements of ISO 15197:2013 as 98.5% to 100% of the results were within the stipulated limits. Furthermore, all results were within the clinically non-critical zones A and B of the consensus error grid for type 1 diabetes. Conclusions The technical improvement of the systems ensured compliance with ISO 15197 in the hands of healthcare professionals even in its more stringent 2013 version. Alternative presentation of system accuracy results in radar plots provides additional information with certain advantages. In addition, the surveillance error grid offers a modern tool to assess a system's clinical performance.

Far-IR transparency and dynamic infrared signature control with novel conducting polymer systems

NASA Astrophysics Data System (ADS)

Chandrasekhar, Prasanna; Dooley, T. J.

1995-09-01

Materials which possess transparency, coupled with active controllability of this transparency in the infrared (IR), are today an increasingly important requirement, for varied applications. These applications include windows for IR sensors, IR-region flat panel displays used in camouflage as well as in communication and sight through night-vision goggles, coatings with dynamically controllable IR-emissivity, and thermal conservation coatings. Among stringent requirements for these applications are large dynamic ranges (color contrast), 'multi-color' or broad-band characteristics, extended cyclability, long memory retention, matrix addressability, small area fabricability, low power consumption, and environmental stability. Among materials possessing the requirements for variation of IR signature, conducting polymers (CPs) appear to be the only materials with dynamic, actively controllable signature and acceptable dynamic range. Conventional CPs such as poly(alkyl thiophene), poly(pyrrole) or poly(aniline) show very limited dynamic range, especially in the far-IR, while also showing poor transparency. We have developed a number of novel CP systems ('system' implying the CP, the selected dopant, the synthesis method, and the electrolyte) with very wide dynamic range (up to 90% in both important IR regions, 3 - 5 (mu) and 8 - 12 (mu) ), high cyclability (to 105 cycles with less than 10% optical degradation), nearly indefinite optical memory retention, matrix addressability of multi-pixel displays, very wide operating temperature and excellent environmental stability, low charge capacity, and processability into areas from less than 1 mm2 to more than 100 cm2. The criteria used to design and arrive at these CP systems, together with representative IR signature data, are presented in this paper.

A Shared Responsibility for Skills

ERIC Educational Resources Information Center

Clough, Bert

2011-01-01

Co-investment between the state, employer, and employee is an intrinsic feature of most vocational and education training systems. The government's strategy is to "profoundly" shift responsibility for funding learning and skills from the state to individuals and businesses. At a time of stringent cuts in publicly-funded further education…

Lubricity of biobased diesel fuels and additives

USDA-ARS?s Scientific Manuscript database

Modern diesel engines rely on the fuel itself to lubricate moving parts in the fuel and engine systems. Prior to the late 1990s, diesel fuel from petroleum provided sufficient lubricity to effectively reduce wear in injectors and fuel pumps. Increasingly stringent limitations on the sulfur content o...