Test anxiety and performance-avoidance goals explain gender differences in SAT-V, SAT-M, and overall SAT scores.

PubMed

Hannon, Brenda

2012-11-01

This study uses analysis of co-variance in order to determine which cognitive/learning (working memory, knowledge integration, epistemic belief of learning) or social/personality factors (test anxiety, performance-avoidance goals) might account for gender differences in SAT-V, SAT-M, and overall SAT scores. The results revealed that none of the cognitive/learning factors accounted for gender differences in SAT performance. However, the social/personality factors of test anxiety and performance-avoidance goals each separately accounted for all of the significant gender differences in SAT-V, SAT-M, and overall SAT performance. Furthermore, when the influences of both of these factors were statistically removed simultaneously, all non-significant gender differences reduced further to become trivial by Cohen's (1988) standards. Taken as a whole, these results suggest that gender differences in SAT-V, SAT-M, and overall SAT performance are a consequence of social/learning factors.

Successful testing and treating of HIV/AIDS in Indonesia depends on the addiction treatment modality

PubMed Central

Iskandar, Shelly; de Jong, Cor AJ; Hidayat, Teddy; Siregar, Ike MP; Achmad, Tri H; van Crevel, Reinout; van der Ven, Andre

2012-01-01

Background In many settings, people who inject drugs (PWID) have limited access to human immunodeficiency virus (HIV) care which is provided in several hospitals and primary health centers in big cities. Substance abuse treatment (SAT) can be used as the entry-point to HIV programs. The aim of this study is to describe the characteristics of the PWID who had accessed SAT and determine which SAT modality associates significantly with HIV programs. Methods PWID were recruited by respondent-driven sampling in an urban setting in Java, Indonesia and interviewed with the Addiction Severity Index (ASI), Blood-Borne Virus Transmission Risk Assessment Questionnaires, and Knowledge Questionnaire on HIV/AIDS. The information regarding the use of substance abuse treatment and HIV program were based on questions in ASI. Results Seventy-seven percent of 210 PWID had accessed SAT at least once. PWID who had accessed a SAT modality reported more severe drug problems. The most widely used SAT were opioid substitution (57%) and traditional/faith-based treatment (56%). Accessing substitution treatment (adjusted odds ratio [OR] = 5.8; 95% confidence interval [CI]: 2.5–13.9) or residential drug-free treatment (adjusted OR = 3.7; 95% CI: 1.4–9.7) was significantly associated with HIV testing, whereas accessing substitution treatment (adjusted OR = 3.8; 95% CI: 1.9–7.5) or other medical services (adjusted OR = 3.1; 95% CI: 1.1–8.7) was significantly associated with HIV treatment. There was no significant association between accessing traditional/faith-based treatment and HIV testing and treatment. Conclusion Efforts should be made to link HIV services with traditional/faith-based treatment to increase the coverage of HIV programs. PMID:23293529

Successful testing and treating of HIV/AIDS in Indonesia depends on the addiction treatment modality.

PubMed

Iskandar, Shelly; de Jong, Cor Aj; Hidayat, Teddy; Siregar, Ike Mp; Achmad, Tri H; van Crevel, Reinout; van der Ven, Andre

2012-01-01

In many settings, people who inject drugs (PWID) have limited access to human immunodeficiency virus (HIV) care which is provided in several hospitals and primary health centers in big cities. Substance abuse treatment (SAT) can be used as the entry-point to HIV programs. The aim of this study is to describe the characteristics of the PWID who had accessed SAT and determine which SAT modality associates significantly with HIV programs. PWID were recruited by respondent-driven sampling in an urban setting in Java, Indonesia and interviewed with the Addiction Severity Index (ASI), Blood-Borne Virus Transmission Risk Assessment Questionnaires, and Knowledge Questionnaire on HIV/AIDS. The information regarding the use of substance abuse treatment and HIV program were based on questions in ASI. Seventy-seven percent of 210 PWID had accessed SAT at least once. PWID who had accessed a SAT modality reported more severe drug problems. The most widely used SAT were opioid substitution (57%) and traditional/faith-based treatment (56%). Accessing substitution treatment (adjusted odds ratio [OR] = 5.8; 95% confidence interval [CI]: 2.5-13.9) or residential drug-free treatment (adjusted OR = 3.7; 95% CI: 1.4-9.7) was significantly associated with HIV testing, whereas accessing substitution treatment (adjusted OR = 3.8; 95% CI: 1.9-7.5) or other medical services (adjusted OR = 3.1; 95% CI: 1.1-8.7) was significantly associated with HIV treatment. There was no significant association between accessing traditional/faith-based treatment and HIV testing and treatment. Efforts should be made to link HIV services with traditional/faith-based treatment to increase the coverage of HIV programs.

Facilitating the exploitation of ERTS imagery using snow enhancement techniques

NASA Technical Reports Server (NTRS)

Wobber, F. J. (Principal Investigator); Martin, K. R.; Sheffield, C.; Russell, O.; Amato, R. V.

1973-01-01

The author has identified the following significant results. EarthSat has established an effective mail-based method for obtaining timely ground truth (snow depth) information over an extensive area. The method is both efficient and inexpensive compared with the cost of a similarly scaled direct field checking effort. Additional geological information has been acquired which is not shown in geological maps in the area. Excellent quality snow-free ERTS-1 transparencies of the test areas have been received and are being analyzed.

Correcting the SAT's Ethnic and Social-Class Bias: A Method for Reestimating SAT Scores.

ERIC Educational Resources Information Center

Freedle, Roy O.

2003-01-01

A corrective scoring method, the Revised-Scholastic Achievement Test (R-SAT), addresses nonrandom ethnic test bias patterns found in the SAT. The R-SAT has been shown to reduce the mean-score difference between African-American and white test-takers by one-third, increase verbal scores by as much as 200-300 points for individuals, and benefit…

VANDENBERG AIR FORCE BASE, CALIF.- The covered SciSat-1 spacecraft is lowered onto a test stand at Vandenberg Air Force Base, Calif., for functional testing. The solar arrays will be attached and the communications systems checked out. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-07-29

VANDENBERG AIR FORCE BASE, CALIF.- The covered SciSat-1 spacecraft is lowered onto a test stand at Vandenberg Air Force Base, Calif., for functional testing. The solar arrays will be attached and the communications systems checked out. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

Nano Entry System for CubeSat-Class Payloads Project (Nano-ADEPT)

NASA Technical Reports Server (NTRS)

Smith, Brandon Patrick

2014-01-01

This project is developing a mechanically deployed system through a mission application study, deployment/ejection testing, and wind tunnel testing. Adaptable Deployable Entry and Placement Technology (ADEPT) has been under development at NASA since 2011. Nano-ADEPT is the application of this revolutionary entry technology for small spacecraft. The unique capability of ADEPT for small science payloads comes from its ability to stow within a slender volume and deploy passively to achieve a mass-efficient drag surface with a high heat rate capability. Near-term applications for this technology include return of small science payloads or CubeSat technology from Low Earth Orbit (LEO) and delivery of secondary payloads to the surface of Mars.

Predicting clinical concussion measures at baseline based on motivation and academic profile.

PubMed

Trinidad, Katrina J; Schmidt, Julianne D; Register-Mihalik, Johna K; Groff, Diane; Goto, Shiho; Guskiewicz, Kevin M

2013-11-01

The purpose of this study was to predict baseline neurocognitive and postural control performance using a measure of motivation, high school grade point average (hsGPA), and Scholastic Aptitude Test (SAT) score. Cross-sectional. Clinical research center. Eighty-eight National Collegiate Athletic Association Division I incoming student-athletes (freshman and transfers). Participants completed baseline clinical concussion measures, including a neurocognitive test battery (CNS Vital Signs), a balance assessment [Sensory Organization Test (SOT)], and motivation testing (Rey Dot Counting). Participants granted permission to access hsGPA and SAT total score. Standard scores for each CNS Vital Signs domain and SOT composite score. Baseline motivation, hsGPA, and SAT explained a small percentage of the variance of complex attention (11%), processing speed (12%), and composite SOT score (20%). Motivation, hsGPA, and total SAT score do not explain a significant amount of the variance in neurocognitive and postural control measures but may still be valuable to consider when interpreting neurocognitive and postural control measures.

Modelling of XCO₂ Surfaces Based on Flight Tests of TanSat Instruments.

PubMed

Zhang, Li Li; Yue, Tian Xiang; Wilson, John P; Wang, Ding Yi; Zhao, Na; Liu, Yu; Liu, Dong Dong; Du, Zheng Ping; Wang, Yi Fu; Lin, Chao; Zheng, Yu Quan; Guo, Jian Hong

2016-11-01

The TanSat carbon satellite is to be launched at the end of 2016. In order to verify the performance of its instruments, a flight test of TanSat instruments was conducted in Jilin Province in September, 2015. The flight test area covered a total area of about 11,000 km² and the underlying surface cover included several lakes, forest land, grassland, wetland, farmland, a thermal power plant and numerous cities and villages. We modeled the column-average dry-air mole fraction of atmospheric carbon dioxide (XCO₂) surface based on flight test data which measured the near- and short-wave infrared (NIR) reflected solar radiation in the absorption bands at around 760 and 1610 nm. However, it is difficult to directly analyze the spatial distribution of XCO₂ in the flight area using the limited flight test data and the approximate surface of XCO₂, which was obtained by regression modeling, which is not very accurate either. We therefore used the high accuracy surface modeling (HASM) platform to fill the gaps where there is no information on XCO₂ in the flight test area, which takes the approximate surface of XCO₂ as its driving field and the XCO₂ observations retrieved from the flight test as its optimum control constraints. High accuracy surfaces of XCO₂ were constructed with HASM based on the flight's observations. The results showed that the mean XCO₂ in the flight test area is about 400 ppm and that XCO₂ over urban areas is much higher than in other places. Compared with OCO-2's XCO₂, the mean difference is 0.7 ppm and the standard deviation is 0.95 ppm. Therefore, the modelling of the XCO₂ surface based on the flight test of the TanSat instruments fell within an expected and acceptable range.

Simulation-To-Flight (STF-1): A Mission to Enable CubeSat Software-Based Validation and Verification

NASA Technical Reports Server (NTRS)

Morris, Justin; Zemerick, Scott; Grubb, Matt; Lucas, John; Jaridi, Majid; Gross, Jason N.; Ohi, Nicholas; Christian, John A.; Vassiliadis, Dimitris; Kadiyala, Anand;

Scanner qualification with IntenCD based reticle error correction

NASA Astrophysics Data System (ADS)

Elblinger, Yair; Finders, Jo; Demarteau, Marcel; Wismans, Onno; Minnaert Janssen, Ingrid; Duray, Frank; Ben Yishai, Michael; Mangan, Shmoolik; Cohen, Yaron; Parizat, Ziv; Attal, Shay; Polonsky, Netanel; Englard, Ilan

2010-03-01

Scanner introduction into the fab production environment is a challenging task. An efficient evaluation of scanner performance matrices during factory acceptance test (FAT) and later on during site acceptance test (SAT) is crucial for minimizing the cycle time for pre and post production-start activities. If done effectively, the matrices of base line performance established during the SAT are used as a reference for scanner performance and fleet matching monitoring and maintenance in the fab environment. Key elements which can influence the cycle time of the SAT, FAT and maintenance cycles are the imaging, process and mask characterizations involved with those cycles. Discrete mask measurement techniques are currently in use to create across-mask CDU maps. By subtracting these maps from their final wafer measurement CDU map counterparts, it is possible to assess the real scanner induced printed errors within certain limitations. The current discrete measurement methods are time consuming and some techniques also overlook mask based effects other than line width variations, such as transmission and phase variations, all of which influence the final printed CD variability. Applied Materials Aera2TM mask inspection tool with IntenCDTM technology can scan the mask at high speed, offer full mask coverage and accurate assessment of all masks induced source of errors simultaneously, making it beneficial for scanner qualifications and performance monitoring. In this paper we report on a study that was done to improve a scanner introduction and qualification process using the IntenCD application to map the mask induced CD non uniformity. We will present the results of six scanners in production and discuss the benefits of the new method.

Mythbusters.

ERIC Educational Resources Information Center

Marlowe, John

2000-01-01

School-bashers bemoaning declining SAT scores since 1967 do not consider the greater numbers of students now taking these tests. Some parents believe children are overtested. Teachers generally are well prepared, and administration is not top-heavy. Business is faster, but not necessarily more efficient than education. (MLH)

The Nucleolar Fibrillarin Protein Is Required for Helper Virus-Independent Long-Distance Trafficking of a Subviral Satellite RNA in Plants[OPEN

PubMed Central

Chang, Chih-Hao; Lee, Shu-Chuan; Lo, Yih-Shan; Wang, Jiun-Da; Shaw, Jane; Chang, Ban-Yang

2016-01-01

RNA trafficking plays pivotal roles in regulating plant development, gene silencing, and adaptation to environmental stress. Satellite RNAs (satRNAs), parasites of viruses, depend on their helper viruses (HVs) for replication, encapsidation, and efficient spread. However, it remains largely unknown how satRNAs interact with viruses and the cellular machinery to undergo trafficking. Here, we show that the P20 protein of Bamboo mosaic potexvirus satRNA (satBaMV) can functionally complement in trans the systemic trafficking of P20-defective satBaMV in infected Nicotiana benthamiana. The transgene-derived satBaMV, uncoupled from HV replication, was able to move autonomously across a graft union identified by RT-qPCR, RNA gel blot, and in situ RT-PCR analyses. Coimmunoprecipitation experiments revealed that the major nucleolar protein fibrillarin is coprecipitated in the P20 protein complex. Notably, silencing fibrillarin suppressed satBaMV-, but not HV-, phloem-based movement following grafting or coinoculation with HV. Confocal microscopy revealed that the P20 protein colocalized with fibrillarin in the nucleoli and formed punctate structures associated with plasmodesmata. The mobile satBaMV RNA appears to exist as ribonucleoprotein (RNP) complex composed of P20 and fibrillarin, whereas BaMV movement proteins, capsid protein, and BaMV RNA are recruited with HV coinfection. Taken together, our findings provide insight into movement of satBaMV via the fibrillarin-satBaMV-P20 RNP complex in phloem-mediated systemic trafficking. PMID:27702772

Target Practice: Reader Response Theory and Teachers' Interpretations of Students' SAT 10 Scores in Data-Based Professional Development

ERIC Educational Resources Information Center

Atkinson, Becky M.

2012-01-01

The study reported in this article examines how teachers read and respond to their students' Stanford Achievement Test 10 (SAT 10) scores with the goal of investigating the assumption that data-based teaching practice is more "objective" and less susceptible to divergent teacher interpretation. The study uses reader response theory to…

DebriSat: The New Hypervelocity Impact Test for Satellite Breakup Fragment Characterization

NASA Technical Reports Server (NTRS)

Cowardin, Heather

2015-01-01

To replicate a hyper-velocity fragmentation event using modern-day spacecraft materials and construction techniques to better improve the existing DoD and NASA breakup models: DebriSat is intended to be representative of modern LEO satellites. Major design decisions were reviewed and approved by Aerospace subject matter experts from different disciplines. DebriSat includes 7 major subsystems. Attitude determination and control system (ADCS), command and data handling (C&DH), electrical power system (EPS), payload, propulsion, telemetry tracking and command (TT&C), and thermal management. To reduce cost, most components are emulated based on existing design of flight hardware and fabricated with the same materials. center dotA key laboratory-based test, Satellite Orbital debris Characterization Impact Test (SOCIT), supporting the development of the DoD and NASA satellite breakup models was conducted at AEDC in 1992. Breakup models based on SOCIT have supported many applications and matched on-orbit events reasonably well over the years.

Characterization of Foot-And-Mouth Disease Viruses (FMDVs) from Ugandan Cattle Outbreaks during 2012-2013: Evidence for Circulation of Multiple Serotypes

PubMed Central

Namatovu, Alice; Tjørnehøj, Kirsten; Belsham, Graham J.; Dhikusooka, Moses T.; Wekesa, Sabenzia N.; Muwanika, Vincent B.; Siegismund, Hans R.; Ayebazibwe, Chrisostom

2015-01-01

To investigate the foot-and-mouth disease virus (FMDV) serotypes circulating in Uganda’s cattle population, both serological and virological analyses of samples from outbreaks that occurred during 2012–2013 were performed. Altogether, 79 sera and 60 oropharyngeal fluid (OP)/tissue/oral swab samples were collected from herds with reported FMD outbreaks in seven different Ugandan districts. Overall, 61/79 (77%) of the cattle sera were positive for antibodies against FMDV by PrioCHECK FMDV NS ELISA and solid phase blocking ELISA detected titres ≥ 80 for serotypes O, SAT 1, SAT 2 and SAT 3 in 41, 45, 30 and 45 of these 61 seropositive samples, respectively. Virus neutralisation tests detected the highest levels of neutralising antibodies (titres ≥ 45) against serotype O in the herds from Kween and Rakai districts, against SAT 1 in the herd from Nwoya district and against SAT 2 in the herds from Kiruhura, Isingiro and Ntungamo districts. The isolation of a SAT 2 FMDV from Isingiro was consistent with the detection of high levels of neutralising antibodies against SAT 2; sequencing (for the VP1 coding region) indicated that this virus belonged to lineage I within this serotype, like the currently used vaccine strain. From the Wakiso district 11 tissue/swab samples were collected; serotype A FMDV, genotype Africa (G-I), was isolated from the epithelial samples. This study shows that within a period of less than one year, FMD outbreaks in Uganda were caused by four different serotypes namely O, A, SAT 1 and SAT 2. Therefore, to enhance the control of FMD in Uganda, there is need for efficient and timely determination of outbreak virus strains/serotypes and vaccine matching. The value of incorporating serotype A antigen into the imported vaccines along with the current serotype O, SAT 1 and SAT 2 strains should be considered. PMID:25664876

Maker of SAT Aims New Test at 8th Graders

ERIC Educational Resources Information Center

Cech, Scott J.

2008-01-01

Officials at the New York City-based College Board last week rolled out their newest product: ReadiStep. No, it is not a new piece of exercise equipment or a whipped dessert topping--it is a test for 8th graders that some critics are calling a pre-PSAT, referring to the Preliminary SAT assessment taken by 9th and 10th graders and owned by the…

Integration of a MicroCAT Propulsion System and a PhoneSat Bus into a 1.5U CubeSat

NASA Technical Reports Server (NTRS)

Agasid, Elwood Floyd; Perez, Andres Dono; Gazulla, Oriol Tintore; Trinh, Greenfield Tran; Uribe, Eddie Anthony; Keidar, Michael; Haque, Samudra; Teel, George

2014-01-01

NASA Ames Research Center and the George Washington University have developed an electric propulsion subsystem that can be integrated into the PhoneSat bus. Experimental tests have shown a reliable performance by firing three different thrusters at various frequencies in vacuum conditions. The three thrusters were controlled by a SmartPhone that was running the PhoneSat software. The subsystem is fully operational and it requires low average power to function (about 0.1 W). The interface consists of a microcontroller that sends a trigger pulses to the PPU (Plasma Processing Unit), which is responsible for the thruster operation. Frequencies ranging from 1 to 50Hz have been tested, showing a strong flexibility. A SmartPhone acts as the main user interface for the selection of commands that control the entire system. The micro cathode arc thruster MicroCAT provides a high 1(sub sp) of 3000s that allows a 4kg satellite to obtain a (delta)V of 300m/s. The system mass is only 200g with a total of volume of 200(cu cm). The propellant is based on a solid cylinder made of Titanium, which is the cathode at the same time. This simplicity in the design avoids miniaturization and manufacturing problems. The characteristics of this thruster allow an array of MicroCATs to perform attitude control and orbital correcton maneuvers that will open the door for the implementation of an extensive collection of new mission concepts and space applications for CubeSats. NASA Ames is currently working on the integration of the system to fit the thrusters and PPU inside a 1.5U CubeSat together with the PhoneSat bus into a 1.5U CubeSat. This satellite is intended to be deployed from the ISS in 2015 and test the functionality of the thrusters by spinning the satellite around its long axis and measure the rotational speed with the phone byros. This test flight will raise the TRL of the propulsion system from 5 to 7 and will be a first test for further CubeSats with propulsion systems, a key subsystem for long duration or interplanetary CubeSat missions.

EMC Test Report: StangSat - CubeSat Program

NASA Technical Reports Server (NTRS)

Carmody, Lynne M.; Aragona, Peter S.

2013-01-01

This report documents the Electromagnetic Interference E M I testing performed on the StangSat; the unit under test (UUT). Testing was per the requirements of MIL STD-461F. The UUT was characterized and passed the radiated emissions (RE102 limit for Spacecraft) testing.

COMPLEXITY&APPROXIMABILITY OF QUANTIFIED&STOCHASTIC CONSTRAINT SATISFACTION PROBLEMS

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

Hunt, H. B.; Marathe, M. V.; Stearns, R. E.

2001-01-01

Let D be an arbitrary (not necessarily finite) nonempty set, let C be a finite set of constant symbols denoting arbitrary elements of D, and let S and T be an arbitrary finite set of finite-arity relations on D. We denote the problem of determining the satisfiability of finite conjunctions of relations in S applied to variables (to variables and symbols in C) by SAT(S) (by SATc(S).) Here, we study simultaneously the complexity of decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. We present simple yet general techniques to characterize simultaneously, the complexity ormore » efficient approximability of a number of versions/variants of the problems SAT(S), Q-SAT(S), S-SAT(S),MAX-Q-SAT(S) etc., for many different such D,C ,S, T. These versions/variants include decision, counting, maximization and approximate maximization problems, for unquantified, quantified and stochastically quantified formulas. Our unified approach is based on the following two basic concepts: (i) strongly-local replacements/reductions and (ii) relational/algebraic represent ability. Some of the results extend the earlier results in [Pa85,LMP99,CF+93,CF+94O]u r techniques and results reported here also provide significant steps towards obtaining dichotomy theorems, for a number of the problems above, including the problems MAX-&-SAT( S), and MAX-S-SAT(S). The discovery of such dichotomy theorems, for unquantified formulas, has received significant recent attention in the literature [CF+93,CF+94,Cr95,KSW97]« less

An Optimum Space-to-Ground Communication Concept for CubeSat Platform Utilizing NASA Space Network and Near Earth Network

NASA Technical Reports Server (NTRS)

Wong, Yen F.; Kegege, Obadiah; Schaire, Scott H.; Bussey, George; Altunc, Serhat; Zhang, Yuwen; Patel Chitra

2016-01-01

National Aeronautics and Space Administration (NASA) CubeSat missions are expected to grow rapidly in the next decade. Higher data rate CubeSats are transitioning away from Amateur Radio bands to higher frequency bands. A high-level communication architecture for future space-to-ground CubeSat communication was proposed within NASA Goddard Space Flight Center. This architecture addresses CubeSat direct-to-ground communication, CubeSat to Tracking Data Relay Satellite System (TDRSS) communication, CubeSat constellation with Mothership direct-to-ground communication, and CubeSat Constellation with Mothership communication through K-Band Single Access (KSA). A study has been performed to explore this communication architecture, through simulations, analyses, and identifying technologies, to develop the optimum communication concepts for CubeSat communications. This paper presents details of the simulation and analysis that include CubeSat swarm, daughter ship/mother ship constellation, Near Earth Network (NEN) S and X-band direct to ground link, TDRSS Multiple Access (MA) array vs Single Access mode, notional transceiver/antenna configurations, ground asset configurations and Code Division Multiple Access (CDMA) signal trades for daughter ship/mother ship CubeSat constellation inter-satellite cross link. Results of space science X-band 10 MHz maximum achievable data rate study are summarized. CubeSat NEN Ka-Band end-to-end communication analysis is provided. Current CubeSat communication technologies capabilities are presented. Compatibility test of the CubeSat transceiver through NEN and SN is discussed. Based on the analyses, signal trade studies and technology assessments, the desired CubeSat transceiver features and operation concepts for future CubeSat end-to-end communications are derived.

The Social Attribution Task-Multiple Choice (SAT-MC): A Psychometric and Equivalence Study of an Alternate Form.

PubMed

Johannesen, Jason K; Lurie, Jessica B; Fiszdon, Joanna M; Bell, Morris D

2013-01-01

The Social Attribution Task-Multiple Choice (SAT-MC) uses a 64-second video of geometric shapes set in motion to portray themes of social relatedness and intentions. Considered a test of "Theory of Mind," the SAT-MC assesses implicit social attribution formation while reducing verbal and basic cognitive demands required of other common measures. We present a comparability analysis of the SAT-MC and the new SAT-MC-II, an alternate form created for repeat testing, in a university sample (n = 92). Score distributions and patterns of association with external validation measures were nearly identical between the two forms, with convergent and discriminant validity supported by association with affect recognition ability and lack of association with basic visual reasoning. Internal consistency of the SAT-MC-II was superior (alpha = .81) to the SAT-MC (alpha = .56). Results support the use of SAT-MC and new SAT-MC-II as equivalent test forms. Demonstrating relatively higher association to social cognitive than basic cognitive abilities, the SAT-MC may provide enhanced sensitivity as an outcome measure of social cognitive intervention trials.

SDO FlatSat Facility

NASA Technical Reports Server (NTRS)

Amason, David L.

2008-01-01

The goal of the Solar Dynamics Observatory (SDO) is to understand and, ideally, predict the solar variations that influence life and society. It's instruments will measure the properties of the Sun and will take hifh definition images of the Sun every few seconds, all day every day. The FlatSat is a high fidelity electrical and functional representation of the SDO spacecraft bus. It is a high fidelity test bed for Integration & Test (I & T), flight software, and flight operations. For I & T purposes FlatSat will be a driver to development and dry run electrical integration procedures, STOL test procedures, page displays, and the command and telemetry database. FlatSat will also serve as a platform for flight software acceptance and systems testing for the flight software system component including the spacecraft main processors, power supply electronics, attitude control electronic, gimbal control electrons and the S-band communications card. FlatSat will also benefit the flight operations team through post-launch flight software code and table update development and verification and verification of new and updated flight operations products. This document highlights the benefits of FlatSat; describes the building of FlatSat; provides FlatSat facility requirements, access roles and responsibilities; and, and discusses FlatSat mechanical and electrical integration and functional testing.

VANDENBERG AIR FORCE BASE, CALIF. - The SciSat-1 spacecraft is revealed at Vandenberg Air Force Base, Calif. Sci-Sat, which will undergo instrument checkout and spacecraft functional testing, weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-06-26

VANDENBERG AIR FORCE BASE, CALIF. - The SciSat-1 spacecraft is revealed at Vandenberg Air Force Base, Calif. Sci-Sat, which will undergo instrument checkout and spacecraft functional testing, weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

VANDENBERG AIR FORCE BASE, CALIF.- The cover is being lifted off SciSat-1 spacecraft at Vandenberg Air Force Base, Calif. Sci-Sat, which will undergo instrument checkout and spacecraft functional testing, weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-06-26

VANDENBERG AIR FORCE BASE, CALIF.- The cover is being lifted off SciSat-1 spacecraft at Vandenberg Air Force Base, Calif. Sci-Sat, which will undergo instrument checkout and spacecraft functional testing, weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

The open prototype for educational NanoSats: Fixing the other side of the small satellite cost equation

NASA Astrophysics Data System (ADS)

Berk, Josh; Straub, Jeremy; Whalen, David

Government supported nano-satellite launch programs and emerging commercial small satellite launch services are reducing the cost of access to space for educational and other CubeSat projects. The cost and complexity of designing and building these satellites remains a vexing complication for many would be CubeSat aspirants. The Open Prototype for Educational NanoSats (OPEN), a proposed nano-satellite development platform, is described in this paper. OPEN endeavors to reduce the costs and risks associated with educational, government and commercial nano-satellite development. OPEN provides free and publicly available plans for building, testing and operating a versatile, low-cost satellite, based on the standardized CubeSat form-factor. OPEN consists of public-domain educational reference plans, complete with engineering schematics, CAD files, construction and test instructions as well as ancillary reference materials relevant to satellite building and operation. By making the plan, to produce a small but capable spacecraft freely available, OPEN seeks to lower the barriers to access on the other side (non-launch costs) of the satellite cost equation.

Comparative Validity of the Descriptive Tests of Mathematical Skills (DTMS) and SAT-Mathematics (SAT-M) for Predicting Performance in Freshman College Mathematics Courses: Prefatory Report

ERIC Educational Resources Information Center

McLoughlin, M. Padraig M. M.; Bluford, Dontrell A.

2004-01-01

This study investigated the predictive validity of the Descriptive Tests of Mathematical Skills (DTMS) and the SAT-Mathematics (SAT-M) tests as placement tools for entering students in a small, liberal arts, historically black institution (HBI) using regression analysis. The placement schema is four-tiered: for a remedial algebra course, college…

VANDENBERG AIR FORCE BASE, CALIF. - The L-1011 carrier aircraft is ready for flight after undergoing a Combined Systems Test, an integrated test involving the Pegasus launch vehicle, SciSat-1 spacecraft and L-1011 aircraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-08-09

VANDENBERG AIR FORCE BASE, CALIF. - The L-1011 carrier aircraft is ready for flight after undergoing a Combined Systems Test, an integrated test involving the Pegasus launch vehicle, SciSat-1 spacecraft and L-1011 aircraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

The Social Attribution Task-Multiple Choice (SAT-MC): A Psychometric and Equivalence Study of an Alternate Form

PubMed Central

Johannesen, Jason K.; Lurie, Jessica B.; Fiszdon, Joanna M.; Bell, Morris D.

2013-01-01

The Social Attribution Task-Multiple Choice (SAT-MC) uses a 64-second video of geometric shapes set in motion to portray themes of social relatedness and intentions. Considered a test of “Theory of Mind,” the SAT-MC assesses implicit social attribution formation while reducing verbal and basic cognitive demands required of other common measures. We present a comparability analysis of the SAT-MC and the new SAT-MC-II, an alternate form created for repeat testing, in a university sample (n = 92). Score distributions and patterns of association with external validation measures were nearly identical between the two forms, with convergent and discriminant validity supported by association with affect recognition ability and lack of association with basic visual reasoning. Internal consistency of the SAT-MC-II was superior (alpha = .81) to the SAT-MC (alpha = .56). Results support the use of SAT-MC and new SAT-MC-II as equivalent test forms. Demonstrating relatively higher association to social cognitive than basic cognitive abilities, the SAT-MC may provide enhanced sensitivity as an outcome measure of social cognitive intervention trials. PMID:23864984

An Optimum Space-to-Ground Communication Concept for CubeSat Platform Utilizing NASA Space Network and Near Earth Network

NASA Technical Reports Server (NTRS)

Wong, Yen F.; Kegege, Obadiah; Schaire, Scott H.; Bussey, George; Altunc, Serhat; Zhang, Yuwen; Patel, Chitra

2016-01-01

National Aeronautics and Space Administration (NASA) CubeSat missions are expected to grow rapidly in the next decade. Higher data rate CubeSats are transitioning away from Amateur Radio bands to higher frequency bands. A high-level communication architecture for future space-to-ground CubeSat communication was proposed within NASA Goddard Space Flight Center. This architecture addresses CubeSat direct-to-ground communication, CubeSat to Tracking Data Relay Satellite System (TDRSS) communication, CubeSat constellation with Mothership direct-to-ground communication, and CubeSat Constellation with Mothership communication through K-Band Single Access (KSA).A Study has been performed to explore this communication architecture, through simulations, analyses, and identifying technologies, to develop the optimum communication concepts for CubeSat communications. This paper will present details of the simulation and analysis that include CubeSat swarm, daughter shipmother ship constellation, Near Earth Network (NEN) S and X-band direct to ground link, TDRS Multiple Access (MA) array vs Single Access mode, notional transceiverantenna configurations, ground asset configurations and Code Division Multiple Access (CDMA) signal trades for daughter mother CubeSat constellation inter-satellite crosslink. Results of Space Science X-band 10 MHz maximum achievable data rate study will be summarized. Assessment of Technology Readiness Level (TRL) of current CubeSat communication technologies capabilities will be presented. Compatibility test of the CubeSat transceiver through NEN and Space Network (SN) will be discussed. Based on the analyses, signal trade studies and technology assessments, the functional design and performance requirements as well as operation concepts for future CubeSat end-to-end communications will be derived.

Study of LEO-SAT microwave link for broad-band mobile satellite communication system

NASA Technical Reports Server (NTRS)

Fujise, Masayuki; Chujo, Wataru; Chiba, Isamu; Furuhama, Yoji; Kawabata, Kazuaki; Konishi, Yoshihiko

1993-01-01

In the field of mobile satellite communications, a system based on low-earth-orbit satellites (LEO-SAT's) such as the Iridium system has been proposed. The LEO-SAT system is able to offer mobile telecommunication services in high-latitude areas. Rain degradation, fading and shadowing are also expected to be decreased when the system is operated at a high elevation angle. Furthermore, the propagation delay generated in the LEO-SAT system is less pronounced than that in the geostationary orbit satellite (GEO-SAT) system and, in voice services, the effect of the delay is almost negligible. We proposed a concept of a broad-band mobile satellite communication system with LEO-SAT's and Optical ISL. In that system, a fixed L-band (1.6/1.5 GHz) multibeam is used to offer narrow band service to the mobile terminals in the entire area covered by a LEO-SAT and steerable Ka-band (30/20 GHz) spot beams are used for the wide band service. In this paper, we present results of a study of LEO-SAT microwave link between a satellite and a mobile terminal for a broad-band mobile satellite communication system. First, the results of link budget calculations are presented and the antennas mounted on satellites are shown. For a future mobile antenna technology, we also show digital beamforming (DBF) techniques. DBF, together with modulation and/or demodulation, is becoming a key technique for mobile antennas with advanced functions such as antenna pattern calibration, correction, and radio interference suppression. In this paper, efficient DBF techniques for transmitting and receiving are presented. Furthermore, an adaptive array antenna system suitable for this LEO-SAT is presented.

DebriSat - A Planned Laboratory-Based Satellite Impact Experiment for Breakup Fragment Characterization

NASA Technical Reports Server (NTRS)

Liou, J.-C.; Fitz-Coy, N.; Werremeyer, M.; Huynh, T.; Voelker, M.; Opiela, J.

2012-01-01

DebriSat is a planned laboratory ]based satellite hypervelocity impact experiment. The goal of the project is to characterize the orbital debris that would be generated by a hypervelocity collision involving a modern satellite in low Earth orbit (LEO). The DebriSat project will update and expand upon the information obtained in the 1992 Satellite Orbital Debris Characterization Impact Test (SOCIT), which characterized the breakup of a 1960 's US Navy Transit satellite. There are three phases to this project: the design and fabrication of an engineering model representing a modern, 50-cm/50-kg class LEO satellite known as DebriSat; conduction of a laboratory-based hypervelocity impact to catastrophically break up the satellite; and characterization of the properties of breakup fragments down to 2 mm in size. The data obtained, including fragment size, area ]to ]mass ratio, density, shape, material composition, optical properties, and radar cross ]section distributions, will be used to supplement the DoD fs and NASA fs satellite breakup models to better describe the breakup outcome of a modern satellite. Updated breakup models will improve mission planning, environmental models, and event response. The DebriSat project is sponsored by the Air Force fs Space and Missile Systems Center and the NASA Orbital Debris Program Office. The design and fabrication of DebriSat is led by University of Florida with subject matter experts f support from The Aerospace Corporation. The major milestones of the project include the complete fabrication of DebriSat by September 2013, the hypervelocity impact of DebriSat at the Air Force fs Arnold Engineering Development Complex in early 2014, and fragment characterization and data analyses in late 2014.

Science-Driven NanoSats Design for Deep Space

NASA Astrophysics Data System (ADS)

Klesh, A. T.; Castillo, J. C.

2012-12-01

CubeSat-based exploration of Earth has driven the development of miniaturized systems and research-grade instruments. The current performance of CubeSats raises the question of their potential contribution to planetary exploration. Two possible applications can be foreseen. One would take advantage of the readily availability of the CubeSat deployer Poly Picosatellite Orbital Deployer (P-POD) for planetary-related observations around Earth (e.g., O/OREOS mission, ExoPlanetSat), and, when propulsion systems develop, for interplanetary exploration. However, the CubeSat formfactor restricts payloads to be in an undeployed volume of 10x10x10 (1U) to 10x20x30 (6U) cm, based on the qualified and accepted P-POD. As a possible alternative, one may leverage the CubeSat-tailored subsystems to operate that platform as a secondary payload on a deep space mission. Whether the CubeSat formfactor constraint might be adjusted to accommodate a broader range of science applications or specific tailoring is required remains to be quantified. Through consultation with a wide range of scientists and engineers, we have examined the possible applications of secondary deep space NanoSats, and what derived requirements stem from these missions. Applications and requirements, together with existing technology, inform on common formfactors that could be useful for future planetary missions. By examining these formfactors, we have identified different categories of NanoSat explorer (additionally imposing discrete requirements on the mothership) that directly support scientific endeavors. In this paper, we outline some of the scientific applications that would drive the NanoSat formfactor design, as well as describe how the requirements affect programmatic issues. Several mission types are considered: passive deployment, active propulsion, targeted landing, and sample return. Each scenario changes the risk posture, and can impose additional considerations. Our goal has been to identify appropriate science driven designs that might serve a similar purpose to the "CubeSat standard", but not bound by the current specification adopted for launch vehicles. Additionally we consider the various technologies needed to successfully carry out deep space NanoSat missions including communication infrastructure (either direct-to-Earth or via relay), navigation / position determination, and avionics survivability. A brief survey of existing systems is presented, with recommendations for development toward future needs. As CubeSats demonstrate greater and greater science capability in low-Earth orbit, it is only natural to attempt to use this technology-driven formfactor to investigate the solar system. Here we merge desired science applications with existing CubeSat lessons-learned and technological ability to determine how we might explore intelligently and efficiently, yet not lose the wisdom we have gained from "thinking inside the box". Acknowledgement: This work has been carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA.

Cryogenic on-orbit liquid depot storage acquisition and transfer (COLD-SAT) experiment subsystem instrumentation and wire harness design report

NASA Technical Reports Server (NTRS)

Edwards, Lawrence G.

1994-01-01

Subcritical cryogens such as liquid hydrogen (LH2) and liquid oxygen (LO2) are required for space based transportation propellant, reactant, and life support systems. Future long-duration space missions will require on-orbit systems capable of long-term cryogen storage and efficient fluid transfer capabilities. COLD-SAT, which stands for cryogenic orbiting liquid depot-storage acquisition and transfer, is a free-flying liquid hydrogen management flight experiment. Experiments to determine optimum methods of fluid storage and transfer will be performed on the COLD-SAT mission. The success of the mission is directly related to the type and accuracy of measurements made. The instrumentation and measurement techniques used are therefore critical to the success of the mission. This paper presents the results of the COLD-SAT experiment subsystem instrumentation and wire harness design effort. Candidate transducers capable of fulfilling the COLD-SAT experiment measurement requirements are identified. Signal conditioning techniques, data acquisition requirements, and measurement uncertainty analysis are presented. Electrical harnessing materials and wiring techniques for the instrumentation designed to minimize heat conduction to the cryogenic tanks and provide optimum measurement accuracy are listed.

A survey of SAT solver

NASA Astrophysics Data System (ADS)

Gong, Weiwei; Zhou, Xu

2017-06-01

In Computer Science, the Boolean Satisfiability Problem(SAT) is the problem of determining if there exists an interpretation that satisfies a given Boolean formula. SAT is one of the first problems that was proven to be NP-complete, which is also fundamental to artificial intelligence, algorithm and hardware design. This paper reviews the main algorithms of the SAT solver in recent years, including serial SAT algorithms, parallel SAT algorithms, SAT algorithms based on GPU, and SAT algorithms based on FPGA. The development of SAT is analyzed comprehensively in this paper. Finally, several possible directions for the development of the SAT problem are proposed.

Construction of a Thermal Vacuum Chamber for Environment Test of Triple CubeSat Mission TRIO-CINEMA

NASA Astrophysics Data System (ADS)

Jeon, Jeheon; Lee, Seongwhan; Yoon, Seyoung; Seon, Jongho; Jin, Ho; Lee, Donghun; Lin, Robert P.

2013-12-01

TRiplet Ionospheric Observatory-CubeSat for Ion, Neutron, Electron & MAgnetic fields (TRIO-CINEMA) is a CubeSat with 3.14 kg in weight and 3-U (10 × 10 × 30 cm) in size, jointly developed by Kyung Hee University and UC Berkeley to measure magnetic fields of near Earth space and detect plasma particles. When a satellite is launched into orbit, it encounters ultrahigh vacuum and extreme temperature. To verify the operation and survivability of the satellite in such an extreme space environment, experimental tests are conducted on the ground using thermal vacuum chamber. This paper describes the temperature control device and monitoring system suitable for CubeSat test environment using the thermal vacuum chamber of the School of Space Research, Kyung Hee University. To build the chamber, we use a general purpose thermal analysis program and NX 6.0 TMG program. We carry out thermal vacuum tests on the two flight models developed by Kyung Hee University based on the thermal model of the TRIO-CINEMA satellite. It is expected from this experiment that proper operation of the satellite in the space environment will be achieved.

Yes, the SAT Does Help Colleges.

ERIC Educational Resources Information Center

Hanford, George H.

1985-01-01

Discusses the Scholastic Aptitude Test (SAT) and its importance to colleges in admissions decisions. The author describes the admissions process, the role of test scores, and the relationships of class ranks and SAT scores to outcomes in college. (CT)

VANDENBERG AIR FORCE BASE, CALIF. - Outside the clean room at Vandenberg Air Force Base, Calif., the SciSat-1 spacecraft (background) has been removed from the shipping container mounting base (lower left) and placed on the handling fixture. Sci-Sat, which will undergo instrument checkout and spacecraft functional testing, weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-06-26

VANDENBERG AIR FORCE BASE, CALIF. - Outside the clean room at Vandenberg Air Force Base, Calif., the SciSat-1 spacecraft (background) has been removed from the shipping container mounting base (lower left) and placed on the handling fixture. Sci-Sat, which will undergo instrument checkout and spacecraft functional testing, weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

VANDENBERG AIR FORCE BASE, CALIF. - At Vandenberg AFB, Calif., a solar array is tested before installing on the SciSat-1 spacecraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-07-29

VANDENBERG AIR FORCE BASE, CALIF. - At Vandenberg AFB, Calif., a solar array is tested before installing on the SciSat-1 spacecraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

VANDENBERG AIR FORCE BASE, CALIF.- At Vandenberg Air Force Base, Calif., spacecraft functional testing is underway on the SciSat-1. The solar arrays are being attached and the communications systems are also being checked out. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-07-12

VANDENBERG AIR FORCE BASE, CALIF.- At Vandenberg Air Force Base, Calif., spacecraft functional testing is underway on the SciSat-1. The solar arrays are being attached and the communications systems are also being checked out. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

VANDENBERG AIR FORCE BASE, CALIF.- A covered SciSat-1 spacecraft sits on a test stand at Vandenberg Air Force Base, Calif. The solar arrays will be attached and the communications systems checked out. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-07-29

VANDENBERG AIR FORCE BASE, CALIF.- A covered SciSat-1 spacecraft sits on a test stand at Vandenberg Air Force Base, Calif. The solar arrays will be attached and the communications systems checked out. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

Preparing for the SAT: A Review

ERIC Educational Resources Information Center

Appelrouth, Jed I.; Zabrucky, Karen M.

2017-01-01

In 2016, more than 1.6 million students took the Scholastic Aptitude Test (SAT), a standardized college admissions test (College Board 2016a). Researchers have estimated that 33 percent of students who take the SAT participate in some mode of formal test preparation, such as private tutoring or classes, to prepare for the exam (Buchmann, Condron…

Theory-Based University Admissions Testing for a New Millennium

ERIC Educational Resources Information Center

Sternberg, Robert J.

2004-01-01

This article describes two projects based on Robert J. Sternberg's theory of successful intelligence and designed to provide theory-based testing for university admissions. The first, Rainbow Project, provided a supplementary test of analytical, practical, and creative skills to augment the SAT in predicting college performance. The Rainbow…

Risk management and statistical multivariate analysis approach for design and optimization of satranidazole nanoparticles.

PubMed

Dhat, Shalaka; Pund, Swati; Kokare, Chandrakant; Sharma, Pankaj; Shrivastava, Birendra

2017-01-01

Rapidly evolving technical and regulatory landscapes of the pharmaceutical product development necessitates risk management with application of multivariate analysis using Process Analytical Technology (PAT) and Quality by Design (QbD). Poorly soluble, high dose drug, Satranidazole was optimally nanoprecipitated (SAT-NP) employing principles of Formulation by Design (FbD). The potential risk factors influencing the critical quality attributes (CQA) of SAT-NP were identified using Ishikawa diagram. Plackett-Burman screening design was adopted to screen the eight critical formulation and process parameters influencing the mean particle size, zeta potential and dissolution efficiency at 30min in pH7.4 dissolution medium. Pareto charts (individual and cumulative) revealed three most critical factors influencing CQA of SAT-NP viz. aqueous stabilizer (Polyvinyl alcohol), release modifier (Eudragit® S 100) and volume of aqueous phase. The levels of these three critical formulation attributes were optimized by FbD within established design space to minimize mean particle size, poly dispersity index, and maximize encapsulation efficiency of SAT-NP. Lenth's and Bayesian analysis along with mathematical modeling of results allowed identification and quantification of critical formulation attributes significantly active on the selected CQAs. The optimized SAT-NP exhibited mean particle size; 216nm, polydispersity index; 0.250, zeta potential; -3.75mV and encapsulation efficiency; 78.3%. The product was lyophilized using mannitol to form readily redispersible powder. X-ray diffraction analysis confirmed the conversion of crystalline SAT to amorphous form. In vitro release of SAT-NP in gradually pH changing media showed <20% release in pH1.2 and pH6.8 in 5h, while, complete release (>95%) in pH7.4 in next 3h, indicative of burst release after a lag time. This investigation demonstrated effective application of risk management and QbD tools in developing site-specific release SAT-NP by nanoprecipitation. Copyright © 2016 Elsevier B.V. All rights reserved.

Racial Differences in Test Preparation Strategies: A Commentary on "Shadow Education, American Style: Test Preparation, the SAT and College Enrollment"

ERIC Educational Resources Information Center

Alon, Sigal

2010-01-01

Claudia Buchmann, Dennis Condron and Vincent Roscigno's study, titled "Shadow Education, American Style: Test Preparation, the SAT and College Enrollment," demonstrates that vigorous use of expensive test preparation tools, such as private classes and tutors, significantly boosts scores on standardized exams such as the SAT or ACT. This…

Trial-to-trial adjustments of speed-accuracy trade-offs in premotor and primary motor cortex

PubMed Central

Guberman, Guido; Cisek, Paul

2016-01-01

Recent studies have shown that activity in sensorimotor structures varies depending on the speed-accuracy trade-off (SAT) context in which a decision is made. Here we tested the hypothesis that the same areas also reflect a more local adjustment of SAT established between individual trials, based on the outcome of the previous decision. Two monkeys performed a reaching decision task in which sensory evidence continuously evolves during the time course of a trial. In two SAT contexts, we compared neural activity in trials following a correct choice vs. those following an error. In dorsal premotor cortex (PMd), we found that 23% of cells exhibited significantly weaker baseline activity after error trials, and for ∼30% of these this effect persisted into the deliberation epoch. These cells also contributed to the process of combining sensory evidence with the growing urgency to commit to a choice. We also found that the activity of 22% of PMd cells was increased after error trials. These neurons appeared to carry less information about sensory evidence and time-dependent urgency. For most of these modulated cells, the effect was independent of whether the previous error was expected or unexpected. We found similar phenomena in primary motor cortex (M1), with 25% of cells decreasing and 34% increasing activity after error trials, but unlike PMd, these neurons showed less clear differences in their response properties. These findings suggest that PMd and M1 belong to a network of brain areas involved in SAT adjustments established using the recent history of reinforcement. NEW & NOTEWORTHY Setting the speed-accuracy trade-off (SAT) is crucial for efficient decision making. Previous studies have reported that subjects adjust their SAT after individual decisions, usually choosing more conservatively after errors, but the neural correlates of this phenomenon are only partially known. Here, we show that neurons in PMd and M1 of monkeys performing a reach decision task support this mechanism by adequately modulating their firing rate as a function of the outcome of the previous decision. PMID:27852735

Nanosatellite optical downlink experiment: design, simulation, and prototyping

NASA Astrophysics Data System (ADS)

Clements, Emily; Aniceto, Raichelle; Barnes, Derek; Caplan, David; Clark, James; Portillo, Iñigo del; Haughwout, Christian; Khatsenko, Maxim; Kingsbury, Ryan; Lee, Myron; Morgan, Rachel; Twichell, Jonathan; Riesing, Kathleen; Yoon, Hyosang; Ziegler, Caleb; Cahoy, Kerri

2016-11-01

The nanosatellite optical downlink experiment (NODE) implements a free-space optical communications (lasercom) capability on a CubeSat platform that can support low earth orbit (LEO) to ground downlink rates>10 Mbps. A primary goal of NODE is to leverage commercially available technologies to provide a scalable and cost-effective alternative to radio-frequency-based communications. The NODE transmitter uses a 200-mW 1550-nm master-oscillator power-amplifier design using power-efficient M-ary pulse position modulation. To facilitate pointing the 0.12-deg downlink beam, NODE augments spacecraft body pointing with a microelectromechanical fast steering mirror (FSM) and uses an 850-nm uplink beacon to an onboard CCD camera. The 30-cm aperture ground telescope uses an infrared camera and FSM for tracking to an avalanche photodiode detector-based receiver. Here, we describe our approach to transition prototype transmitter and receiver designs to a full end-to-end CubeSat-scale system. This includes link budget refinement, drive electronics miniaturization, packaging reduction, improvements to pointing and attitude estimation, implementation of modulation, coding, and interleaving, and ground station receiver design. We capture trades and technology development needs and outline plans for integrated system ground testing.

A Small Aircraft Transportation System (SATS) Demand Model

NASA Technical Reports Server (NTRS)

Long, Dou; Lee, David; Johnson, Jesse; Kostiuk, Peter; Yackovetsky, Robert (Technical Monitor)

2001-01-01

The Small Aircraft Transportation System (SATS) demand modeling is a tool that will be useful for decision-makers to analyze SATS demands in both airport and airspace. We constructed a series of models following the general top-down, modular principles in systems engineering. There are three principal models, SATS Airport Demand Model (SATS-ADM), SATS Flight Demand Model (SATS-FDM), and LMINET-SATS. SATS-ADM models SATS operations, by aircraft type, from the forecasts in fleet, configuration and performance, utilization, and traffic mixture. Given the SATS airport operations such as the ones generated by SATS-ADM, SATS-FDM constructs the SATS origin and destination (O&D) traffic flow based on the solution of the gravity model, from which it then generates SATS flights using the Monte Carlo simulation based on the departure time-of-day profile. LMINET-SATS, an extension of LMINET, models SATS demands at airspace and airport by all aircraft operations in US The models use parameters to provide the user with flexibility and ease of use to generate SATS demand for different scenarios. Several case studies are included to illustrate the use of the models, which are useful to identify the need for a new air traffic management system to cope with SATS.

Autonomous, agile micro-satellites and supporting technologies

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

Breitfeller, E; Dittman, M D; Gaughan, R J

1999-07-19

This paper updates the on-going effort at Lawrence Livermore National Laboratory to develop autonomous, agile micro-satellites (MicroSats). The objective of this development effort is to develop MicroSats weighing only a few tens of kilograms, that are able to autonomously perform precision maneuvers and can be used telerobotically in a variety of mission modes. The required capabilities include satellite rendezvous, inspection, proximity-operations, docking, and servicing. The MicroSat carries an integrated proximity-operations sensor-suite incorporating advanced avionics. A new self-pressurizing propulsion system utilizing a miniaturized pump and non-toxic mono-propellant hydrogen peroxide was successfully tested. This system can provide a nominal 25 kg MicroSatmore » with 200-300 m/s delta-v including a warm-gas attitude control system. The avionics is based on the latest PowerPC processor using a CompactPCI bus architecture, which is modular, high-performance and processor-independent. This leverages commercial-off-the-shelf (COTS) technologies and minimizes the effects of future changes in processors. The MicroSat software development environment uses the Vx-Works real-time operating system (RTOS) that provides a rapid development environment for integration of new software modules, allowing early integration and test. We will summarize results of recent integrated ground flight testing of our latest non-toxic pumped propulsion MicroSat testbed vehicle operated on our unique dynamic air-rail.« less

Complexity and approximability of quantified and stochastic constraint satisfaction problems

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

Hunt, H. B.; Stearns, R. L.; Marathe, M. V.

2001-01-01

Let D be an arbitrary (not necessarily finite) nonempty set, let C be a finite set of constant symbols denoting arbitrary elements of D, and let S be an arbitrary finite set of finite-arity relations on D. We denote the problem of determining the satisfiability of finite conjunctions of relations in S applied to variables (to variables and symbols in C) by SAT(S) (by SAT{sub c}(S)). Here, we study simultaneously the complexity of and the existence of efficient approximation algorithms for a number of variants of the problems SAT(S) and SAT{sub c}(S), and for many different D, C, and S.more » These problem variants include decision and optimization problems, for formulas, quantified formulas stochastically-quantified formulas. We denote these problems by Q-SAT(S), MAX-Q-SAT(S), S-SAT(S), MAX-S-SAT(S) MAX-NSF-Q-SAT(S) and MAX-NSF-S-SAT(S). The main contribution is the development of a unified predictive theory for characterizing the the complexity of these problems. Our unified approach is based on the following basic two basic concepts: (i) strongly-local replacements/reductions and (ii) relational/algebraic representability. Let k {ge} 2. Let S be a finite set of finite-arity relations on {Sigma}{sub k} with the following condition on S: All finite arity relations on {Sigma}{sub k} can be represented as finite existentially-quantified conjunctions of relations in S applied to variables (to variables and constant symbols in C), Then we prove the following new results: (1) The problems SAT(S) and SAT{sub c}(S) are both NQL-complete and {le}{sub logn}{sup bw}-complete for NP. (2) The problems Q-SAT(S), Q-SAT{sub c}(S), are PSPACE-complete. Letting k = 2, the problem S-SAT(S) and S-SAT{sub c}(S) are PSPACE-complete. (3) {exists} {epsilon} > 0 for which approximating the problems MAX-Q-SAT(S) within {epsilon} times optimum is PSPACE-hard. Letting k =: 2, {exists} {epsilon} > 0 for which approximating the problems MAX-S-SAT(S) within {epsilon} times optimum is PSPACE-hard. (4) {forall} {epsilon} > 0 the problems MAX-NSF-Q-SAT(S) and MAX-NSF-S-SAT(S), are PSPACE-hard to approximate within a factor of n{sup {epsilon}} times optimum. These results significantly extend the earlier results by (i) Papadimitriou [Pa851] on complexity of stochastic satisfiability, (ii) Condon, Feigenbaum, Lund and Shor [CF+93, CF+94] by identifying natural classes of PSPACE-hard optimization problems with provably PSPACE-hard {epsilon}-approximation problems. Moreover, most of our results hold not just for Boolean relations: most previous results were done only in the context of Boolean domains. The results also constitute as a significant step towards obtaining a dichotomy theorems for the problems MAX-S-SAT(S) and MAX-Q-SAT(S): a research area of recent interest [CF+93, CF+94, Cr95, KSW97, LMP99].« less

The Social Attribution Task - Multiple Choice (SAT-MC): Psychometric comparison with social cognitive measures for schizophrenia research.

PubMed

Johannesen, Jason K; Fiszdon, Joanna M; Weinstein, Andrea; Ciosek, David; Bell, Morris D

2018-04-01

The Social Attribution Task-Multiple Choice (SAT-MC) tests the ability to extract social themes from viewed object motion. This form of animacy perception is thought to aid the development of social inference, but appears impaired in schizophrenia. The current study was undertaken to examine psychometric equivalence of two forms of the SAT-MC and to compare their performance against social cognitive tests recommended for schizophrenia research. Thirty-two schizophrenia (SZ) and 30 substance use disorder (SUD) participants completed both SAT-MC forms, the Bell-Lysaker Emotion Recognition Task (BLERT), Hinting Task, The Awareness of Social Inference Test (TASIT), Ambiguous Intentions and Hostility Questionnaire (AIHQ) and questionnaire measures of interpersonal function. Test sensitivity, construct and external validity, test-retest reliability, and internal consistency were evaluated. SZ scored significantly lower than SUD on both SAT-MC forms, each classifying ~60% of SZ as impaired, compared with ~30% of SUD. SAT-MC forms demonstrated good test-retest and parallel form reliability, minimal practice effect, high internal consistency, and similar patterns of correlation with social cognitive and external validity measures. The SAT-MC compared favorably to recommended social cognitive tests across psychometric features and, with exception of TASIT, was most sensitive to impairment in schizophrenia when compared to a chronic substance use sample. Published by Elsevier B.V.

DebriSat - A Planned Laboratory-Based Satellite Impact Experiment for Breakup Fragment Characterizations

NASA Technical Reports Server (NTRS)

Liou, Jer-Chyi; Clark, S.; Fitz-Coy, N.; Huynh, T.; Opiela, J.; Polk, M.; Roebuck, B.; Rushing, R.; Sorge, M.; Werremeyer, M.

2013-01-01

The goal of the DebriSat project is to characterize fragments generated by a hypervelocity collision involving a modern satellite in low Earth orbit (LEO). The DebriSat project will update and expand upon the information obtained in the 1992 Satellite Orbital Debris Characterization Impact Test (SOCIT), which characterized the breakup of a 1960 s US Navy Transit satellite. There are three phases to this project: the design and fabrication of DebriSat - an engineering model representing a modern, 60-cm/50-kg class LEO satellite; conduction of a laboratory-based hypervelocity impact to catastrophically break up the satellite; and characterization of the properties of breakup fragments down to 2 mm in size. The data obtained, including fragment size, area-to-mass ratio, density, shape, material composition, optical properties, and radar cross-section distributions, will be used to supplement the DoD s and NASA s satellite breakup models to better describe the breakup outcome of a modern satellite.

The SAT: An Essay in Uncertainty

ERIC Educational Resources Information Center

Mlodinow, Leonard

2008-01-01

In this article, the author talks about the release of the most comprehensive study of SAT exams. The headline on the Web site of the College Board, the maker of the test, was, "SAT Studies Show Test's Strength in Predicting College Success." At the same time, a headline on the Web site of the group FairTest, a 23-year-old, nonprofit…

Reconsidering the SAT-I for College Admissions: Analysis of Alternate Predictors of College Success.

ERIC Educational Resources Information Center

Armstrong, William B.; Carty, Heidi M.

The University of California is engaged in the elimination of the Scholastic Assessment Test I (SAT-I) Verbal and Mathematics tests as a requirement for freshman admission. Opponents of the SAT-I argue that the tests do not measure the outcomes of the high school curriculum and hence do not reflect student learning in secondary school. Proponents…

Handicapped Students and the SAT.

ERIC Educational Resources Information Center

Ragosta, Marjorie

A pilot study of handicapped students and the Scholastic Aptitude Test (SAT) was designed to assess the concerns of handicapped students about the SAT, to identify problems specific to certain disabilities or common across disabilities, to alert the College Board and Educational Testing Service (ETS) about the findings, and to make recommendations…

Surviving Without the SAT

ERIC Educational Resources Information Center

McDermott, Ann

2008-01-01

Scholastic Aptitude Test (SAT) scores still wield a mighty force in American culture and in the psyches of teenagers, even though 760 American colleges and universities have made standardized testing an optional part of the admissions process. Three years ago, after the new writing portion of the SAT was unveiled, the author's college, the College…

The QBito CubeSat: Applications in Space Engineering Education at Technical University of Madrid

NASA Astrophysics Data System (ADS)

Fernandez Fraile, Jose Javier; Laverón-Simavilla, Ana; Calvo, Daniel; Moreno Benavides, Efren

The QBito CubeSat is one of the 50 CubeSats that is being developed for the QB50 project. The project is funded by the 7 (th) Frame Program to launch 50 CubeSats in a ‘string-of-pearls’ configuration for multi-point, in-situ measurements in the lower thermosphere and re-entry research. The 50 CubeSats, developed by an international network of universities and research institutions, will comprise 40 double CubeSats with atmospheric sensors and 10 double or triple CubeSats for science and technology demonstration. It will be the first large-scale CubeSat constellation in orbit; a concept that has been under discussion for several years but not implemented up to now. This project has a high educational interest for universities; beyond the scientific and technological results, being part of an international group of over 90 universities all over the world working and sharing knowledge to achieve a successful mission represents an exciting opportunity. The QBito project main educational motivation is to educate students in space technologies and in space systems engineering. The Universidad Politécnica de Madrid (UPM) is designing, developing, building and testing one of the double CubeSats carrying as payload a kit of atmospheric sensors from the consortium, and other payloads developed by the team such as an IR non-refrigerated sensor, a Phase Change Material (PCM) for thermal control applications, a Fuzzy Logic Attitude Control System and other technological developments such as an optimized antenna deployment mechanism, a lightweight multi-mission configurable structure, and an efficient Electric Power System (EPS) with a Maximum Peak Power Tracker (MPPT). This project has been integrated in the training of the Aerospatiale Engineering, Master and PhD degree students by involving them in the complete engineering process, from its conceptual design to the post-flight conclusions. Three subsystems have been selected for being developed from the conceptual design stage to the flight device: structure, electrical power system and antenna deployment mechanism. In this work, the main characteristics adopted for structure are presented. The project has already provided very interesting lessons to all the people involved, not only students.

Characterization of Orbital Debris Via Hyper-Velocity Ground-Based Tests

NASA Technical Reports Server (NTRS)

Cowardin, Heather

2015-01-01

To replicate a hyper-velocity fragmentation event using modern-day spacecraft materials and construction techniques to better improve the existing DoD and NASA breakup models. DebriSat is intended to be representative of modern LEO satellites.Major design decisions were reviewed and approved by Aerospace subject matter experts from different disciplines. DebriSat includes 7 major subsystems. Attitude determination and control system (ADCS), command and data handling (C&DH), electrical power system (EPS), payload, propulsion, telemetry tracking and command (TT&C), and thermal management. To reduce cost, most components are emulated based on existing design of flight hardware and fabricated with the same materials. A key laboratory-based test, Satellite Orbital debris Characterization Impact Test (SOCIT), supporting the development of the DoD and NASA satellite breakup models was conducted at AEDC in 1992 .Breakup models based on SOCIT have supported many applications and matched on-orbit events reasonably well over the years.

The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Flight Experiment

NASA Technical Reports Server (NTRS)

Williams, Daniel M.; Murdoch, Jennifer L.; Adams, Catherine H.

2005-01-01

This paper provides a summary of conclusions from the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) Flight Experiment which NASA conducted to determine pilot acceptability of the HVO concept for normal conditions. The SATS HVO concept improves efficiency at non-towered, non-radar airports in Instrument Meteorological Conditions (IMC) while achieving a level of safety equal to today s system. Reported are results from flight experiment data that indicate that the SATS HVO concept is viable. The success of the SATS HVO concept is based on acceptable pilot workload, performance, and subjective criteria when compared to the procedural control operations in use today at non-towered, non-radar controlled airfields in IMC. The HVO Flight Experiment, flown on NASA's Cirrus SR22, used a subset of the HVO Simulation Experiment scenarios and evaluation pilots in order to validate the simulation experiment results. HVO and Baseline (today s system) scenarios flown included: single aircraft arriving for a GPS non-precision approach; aircraft arriving for the approach with multiple traffic aircraft; and aircraft arriving for the approach with multiple traffic aircraft and then conducting a missed approach. Results reveal that all twelve low-time instrument-rated pilots preferred SATS HVO when compared to current procedural separation operations. These pilots also flew the HVO procedures safely and proficiently without additional workload in comparison to today s system (Baseline). Detailed results of pilot flight technical error, and their subjective assessments of workload and situation awareness are presented in this paper.

Artificial bee colony in neuro - Symbolic integration

NASA Astrophysics Data System (ADS)

Kasihmuddin, Mohd Shareduwan Mohd; Sathasivam, Saratha; Mansor, Mohd. Asyraf

2017-08-01

Swarm intelligence is a research area that models the population of the swarm based on natural computation. Artificial bee colony (ABC) algorithm is a swarm based metaheuristic algorithm introduced by Karaboga to optimize numerical problem. Pattern-SAT is a pattern reconstruction paradigm that utilized 2SAT logical rule in representing the behavior of the desired pattern. The information of the desired pattern in terms of 2SAT logic is embedded to Hopfield neural network (HNN-P2SAT) and the desired pattern is reconstructed during the retrieval phase. Since the performance of HNN-P2SAT in Pattern-SAT deteriorates when the number of 2SAT clause increased, newly improved ABC is used to reduce the computation burden during the learning phase of HNN-P2SAT (HNN-P2SATABC). The aim of this study is to investigate the performance of Pattern-SAT produced by ABC incorporated with HNN-P2SAT and compare it with conventional standalone HNN. The comparison is examined by using Microsoft Visual Basic C++ 2013 software. The detailed comparison in doing Pattern-SAT is discussed based on global Pattern-SAT, ratio of activated clauses and computation time. The result obtained from computer simulation indicates the beneficial features of HNN-P2SATABC in doing Pattern-SAT. This finding is expected to result in a significant implication on the choice of searching method used to do Pattern-SAT.

High Data Rates for AubieSat-2 A & B, Two CubeSats Performing High Energy Science in the Upper Atmosphere

NASA Technical Reports Server (NTRS)

Sims, William H.

2015-01-01

This paper will discuss a proposed CubeSat size (3 Units / 6 Units) telemetry system concept being developed at Marshall Space Flight Center (MSFC) in cooperation with Auburn University. The telemetry system incorporates efficient, high-bandwidth communications by developing flight-ready, low-cost, PROTOFLIGHT software defined radio (SDR) payload for use on CubeSats. The current telemetry system is slightly larger in dimension of footprint than required to fit within a 0.75 Unit CubeSat volume. Extensible and modular communications for CubeSat technologies will provide high data rates for science experiments performed by two CubeSats flying in formation in Low Earth Orbit. The project is a collaboration between the University of Alabama in Huntsville and Auburn University to study high energy phenomena in the upper atmosphere. Higher bandwidth capacity will enable high-volume, low error-rate data transfer to and from the CubeSats, while also providing additional bandwidth and error correction margin to accommodate more complex encryption algorithms and higher user volume.

Crucial design issues for special access technology; a Delphi study.

PubMed

O'Rourke, Pearl; Ekins, Ray; Timmins, Bernard; Timmins, Fiona; Long, Siobhan; Coyle, Eugene

2014-01-01

To develop and demonstrate a method to involve professional users of assistive technology (AT) in the development process of customisable products. Employing the ideas of user participation and mass customisation, this research addresses the need for reduced product costs and optimised product flexibility. An adaptable six-question Delphi study was developed to establish consensus among AT professionals on design issues relating to a specified AT domain requiring innovation. The study is demonstrated for the special access technology (SAT) domain. A modified morphological matrix structures the application of the study results to the product design process. Fourteen professionals from the Republic of Ireland and the UK participated. Consensus was reached on prevalent parts of SAT that malfunction, primary reasons for SAT malfunction, characteristics of clients associated with SAT selection, client needs regarding SAT use and training, desirable traits of SAT and clinicians' frustrations with SAT. The study revealed a range of problems related to SAT, highlighting the complexities of successful SAT adoption. The questions led to differentiated insights and enabled design solution conceptualisation from various perspectives. The approach was found to help facilitate efficient generation and application of professional users' knowledge during the design process of customisable AT.

An Econometric Model of the Scholastic Aptitude Test Performance of State Educational Systems.

ERIC Educational Resources Information Center

Hashway, Robert M.; And Others

1991-01-01

Nationwide data were partitioned into wealth, fiscal policy, fiscal orientation, and Scholastic Aptitude Test (SAT) performance and participation. Largest between-group differences show that low SAT achieving states have a larger percentage of seniors taking the SAT, along with higher per capita income, per pupil expenditures, and teacher…

Integration and Environmental Qualification Testing of Spacecraft Structures in Support of the Naval Postgraduate School CubeSat Launcher Program

DTIC Science & Technology

2009-06-01

2 3. Space Access Challenges to the CubeSat Community........ 3 B. NPSCUL/NPSCUL-LITE PROGRAM HISTORY TO DATE...Astronautics, AIAA Space 2008 Conference and Exhibition, 2008. 3 3. Space Access Challenges to the CubeSat Community In less than ten years since... challenges to space access for CubeSats.5 Launch of a CubeSat aboard US launch vehicles from US launch facilities would allow CubeSats of a sensitive nature

Ultra-Compact Ka-Band Parabolic Deployable Antenna for RADAR and Interplanetary CubeSats

NASA Technical Reports Server (NTRS)

Sauder, Jonathan; Chahat, Nacer; Thomson, Mark; Hodges, Richard; Peral, Eva; Rahmat-Samii, Yahya

2015-01-01

Over the past several years, technology and launch opportunities for CubeSats have exploded, enabling a wide variety of missions. However, as instruments become more complex and CubeSats travel deeper into space, data communication rates become an issue. To solve this challenge, JPL has initiated a research and technology development effort to design a 0.5 meter Ka-band parabolic deployable antenna (KaPDA) which would stow in 1.5U (10 x 10 x 15 cu cm) and provide 42dB of gain (50% efficiency). A folding rib architecture and dual reflector Cassegrainian design was selected as it best balances RF gain and stowed size. The design implements an innovative telescoping waveguide and gas powered deployment. RF simulations show that after losses, the antenna would have over 42 dB gain, supported by preliminary test results. KaPDA would create opportunities for a host of new CubeSat missions by allowing high data rate communication which would enable using high fidelity instruments or venturing further into deep space, including potential interplanetary missions. Additionally KaPDA would provide a solution for other small antenna needs and the opportunity to obtain Earth science data. This paper discusses the design challenges encountered, the architecture of the solution, and the antennas expected performance capabilities.

Colleges Making SAT Optional as Admissions Requirement

ERIC Educational Resources Information Center

Gilroy, Marilyn

2007-01-01

This article reports that more colleges are dropping the SAT as a requirement for admission and, in many cases, these institutions are attracting a larger and more diverse pool of applicants. According to the National Center for Fair & Open Testing (FairTest), 740 schools have made the SATs optional. The list includes some of the nation's most…

Performance Test for the SIGMA Communication System

NASA Astrophysics Data System (ADS)

Jeong, Seonyeong; Lee, Hyojeong; Lee, Seongwhan; Shin, Jehyuck; Lee, Jungkyu; Jin, Ho

2016-12-01

Scientific CubeSat with Instruments for Global Magnetic Fields and Radiations (SIGMA) is a 3-U size CubeSat that will be operated in low earth orbit (LEO). The SIGMA communication system uses a very high frequency (VHF) band for uplink and an ultra high frequency (UHF) band for downlink. Both frequencies belong to an amateur band. The ground station that communicates with SIGMA is located at Kyung Hee Astronomical Observatory (KHAO). For reliable communication, we carried out a laboratory (LAB) test and far-field tests between the CubeSat and a ground station. In the field test, we considered test parameters such as attenuation, antenna deployment, CubeSat body attitude, and Doppler frequency shift in transmitting commands and receiving data. In this paper, we present a communication performance test of SIGMA, a link budget analysis, and a field test process. We also compare the link budget with the field test results of transmitting commands and receiving data.

Selecting soybean resistant to the cyst nematode Heterodera glycines using simple sequence repeat (microssatellite) markers.

PubMed

Espindola, S M C G; Hamawaki, O T; Oliveira, A P; Hamawaki, C D L; Hamawaki, R L; Takahashi, L M

2016-03-11

The soybean cyst nematode (SCN) is a major cause of soybean yield reduction. The objective of this study was to evaluate the efficiency of marker-assisted selection to identify genotypes resistant to SCN race 3 infection, using Sat_168 and Sat-141 resistance quantitative trait loci. The experiment was carried out under greenhouse conditions, using soybean populations originated from crosses between susceptible and resistant parent stock: CD-201 (susceptible) and Foster IAC (resistant), Conquista (susceptible) and S83-30 (resistant), La-Suprema (susceptible) and S57-11 (resistant), and Parecis (susceptible) and S65-50 (resistant). Plants were inoculated with SCN and evaluated according to the female index (FI), those with FI < 10% were classified as resistant to nematode infection. Plants were genotyped for SCN resistance using microsatellite markers Sat-141 and Sat_168. Marker selection efficiency was analyzed by a contingency table, taking into account genotypic versus phenotypic evaluations for each line. These markers were shown to be useful tool for selection of SCN race 3.

Severe Accident Test Station Activity Report

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

Pint, Bruce A.; Terrani, Kurt A.

2015-06-01

Enhancing safety margins in light water reactor (LWR) severe accidents is currently the focus of a number of international R&D programs. The current UO2/Zr-based alloy fuel system is particularly susceptible since the Zr-based cladding experiences rapid oxidation kinetics in steam at elevated temperatures. Therefore, alternative cladding materials that offer slower oxidation kinetics and a smaller enthalpy of oxidation can significantly reduce the rate of heat and hydrogen generation in the core during a coolant-limited severe accident. In the U.S. program, the high temperature steam oxidation performance of accident tolerant fuel (ATF) cladding solutions has been evaluated in the Severe Accidentmore » Test Station (SATS) at Oak Ridge National Laboratory (ORNL) since 2012. This report summarizes the capabilities of the SATS and provides an overview of the oxidation kinetics of several candidate cladding materials. A suggested baseline for evaluating ATF candidates is a two order of magnitude reduction in the steam oxidation resistance above 1000ºC compared to Zr-based alloys. The ATF candidates are categorized based on the protective external oxide or scale that forms during exposure to steam at high temperature: chromia, alumina, and silica. Comparisons are made to literature and SATS data for Zr-based alloys and other less-protective materials.« less

Human computer interactions in next-generation of aircraft smart navigation management systems: task analysis and architecture under an agent-oriented methodological approach.

PubMed

Canino-Rodríguez, José M; García-Herrero, Jesús; Besada-Portas, Juan; Ravelo-García, Antonio G; Travieso-González, Carlos; Alonso-Hernández, Jesús B

2015-03-04

The limited efficiency of current air traffic systems will require a next-generation of Smart Air Traffic System (SATS) that relies on current technological advances. This challenge means a transition toward a new navigation and air-traffic procedures paradigm, where pilots and air traffic controllers perform and coordinate their activities according to new roles and technological supports. The design of new Human-Computer Interactions (HCI) for performing these activities is a key element of SATS. However efforts for developing such tools need to be inspired on a parallel characterization of hypothetical air traffic scenarios compatible with current ones. This paper is focused on airborne HCI into SATS where cockpit inputs came from aircraft navigation systems, surrounding traffic situation, controllers' indications, etc. So the HCI is intended to enhance situation awareness and decision-making through pilot cockpit. This work approach considers SATS as a system distributed on a large-scale with uncertainty in a dynamic environment. Therefore, a multi-agent systems based approach is well suited for modeling such an environment. We demonstrate that current methodologies for designing multi-agent systems are a useful tool to characterize HCI. We specifically illustrate how the selected methodological approach provides enough guidelines to obtain a cockpit HCI design that complies with future SATS specifications.

Human Computer Interactions in Next-Generation of Aircraft Smart Navigation Management Systems: Task Analysis and Architecture under an Agent-Oriented Methodological Approach

PubMed Central

Canino-Rodríguez, José M.; García-Herrero, Jesús; Besada-Portas, Juan; Ravelo-García, Antonio G.; Travieso-González, Carlos; Alonso-Hernández, Jesús B.

2015-01-01

The limited efficiency of current air traffic systems will require a next-generation of Smart Air Traffic System (SATS) that relies on current technological advances. This challenge means a transition toward a new navigation and air-traffic procedures paradigm, where pilots and air traffic controllers perform and coordinate their activities according to new roles and technological supports. The design of new Human-Computer Interactions (HCI) for performing these activities is a key element of SATS. However efforts for developing such tools need to be inspired on a parallel characterization of hypothetical air traffic scenarios compatible with current ones. This paper is focused on airborne HCI into SATS where cockpit inputs came from aircraft navigation systems, surrounding traffic situation, controllers’ indications, etc. So the HCI is intended to enhance situation awareness and decision-making through pilot cockpit. This work approach considers SATS as a system distributed on a large-scale with uncertainty in a dynamic environment. Therefore, a multi-agent systems based approach is well suited for modeling such an environment. We demonstrate that current methodologies for designing multi-agent systems are a useful tool to characterize HCI. We specifically illustrate how the selected methodological approach provides enough guidelines to obtain a cockpit HCI design that complies with future SATS specifications. PMID:25746092

[Diagnosis of human brucellosis. Role of pH in the seroagglutination test and influence of pH on the agglutinating activity of IgM, IgG and IgA antibodies].

PubMed

Rubio Vallejo, Manuel; del Pozo, José L; Del Pozo León, José Luis; Hernández-Molina, Juan Manuel; Dorronsoro Ibero, Inés; Marrodán Ciordia, Teresa; Díaz García, Ramón

2002-04-01

To evaluate the role of pH in the seroagglutination test (SAT)and Rose Bengal (RB) test, and to determine the influence of pH on the agglutinating activity of IgM, IgG and IgA antibodies. The SAT was performed at pH 7.2 or pH 5.0 in standard microtiter-type polystyrene plates using Ring Test antigen or the Brucella suspension (BRUCAPT) provided in the Brucellacapt kits. Specific antibodies against native hapten were determined by radial immunodiffusion. Additionally, IgG, IgA and IgM fractions were separated from 8 sera by absorption chromatography and their agglutinating capacity was studied at pH 7.2 and 5.0. We studied 72 sera from patients with clinical brucellosis taken at the time of hospitalization, 16 from persons in contact with infected animals, and 16 from healthy donors. SAT results at pH 5.0 correlated with those obtained with the Rose Bengal test. Four Rose Bengal-positive sera were found to be SAT-negative at pH 7.2 and SAT-positive at pH 5.0. SAT performed at pH 5.0 with BRUCAPT antigen yielded higher titers than tests performed at pH 7.2 or 5.0 with Ring Test antigen (p < 0.001), with highest titers in IDR-positive sera. Among the 8 IgG fractions, all but one agglutinated at pH 7.2, and in 4, IgG titers showed significant increases at pH 5.0. Three IgA fractions were SAT-negative at pH 7.2 and SAT-positive at pH 5.0; the other 5 agglutinated at both pH conditions and were DTT-sensitive. All IgA fractions but one were positive by Rose Bengal. Agglutinating activity of the IgM fraction was not affected by pH. The SAT performed with the buffer and antigen suspension included in the Brucellacapt kit (pH 5.0) is highly useful for detecting agglutinating and non-agglutinating antibodies at pH 7.2.

The Trypanosoma cruzi Satellite DNA OligoC-TesT and Trypanosoma cruzi Kinetoplast DNA OligoC-TesT for Diagnosis of Chagas Disease: A Multi-cohort Comparative Evaluation Study

PubMed Central

De Winne, Koen; Büscher, Philippe; Luquetti, Alejandro O.; Tavares, Suelene B. N.; Oliveira, Rodrigo A.; Solari, Aldo; Zulantay, Ines; Apt, Werner; Diosque, Patricio; Monje Rumi, Mercedes; Gironès, Nuria; Fresno, Manuel; Lopez-Velez, Rogelio; Perez-Molina, José A.; Monge-Maillo, Begoña; Garcia, Lineth; Deborggraeve, Stijn

2014-01-01

Background The Trypanosoma cruzi satellite DNA (satDNA) OligoC-TesT is a standardised PCR format for diagnosis of Chagas disease. The sensitivity of the test is lower for discrete typing unit (DTU) TcI than for TcII-VI and the test has not been evaluated in chronic Chagas disease patients. Methodology/Principal Findings We developed a new prototype of the OligoC-TesT based on kinetoplast DNA (kDNA) detection. We evaluated the satDNA and kDNA OligoC-TesTs in a multi-cohort study with 187 chronic Chagas patients and 88 healthy endemic controls recruited in Argentina, Chile and Spain and 26 diseased non-endemic controls from D.R. Congo and Sudan. All specimens were tested in duplicate. The overall specificity in the controls was 99.1% (95% CI 95.2%–99.8%) for the satDNA OligoC-TesT and 97.4% (95% CI 92.6%–99.1%) for the kDNA OligoC-TesT. The overall sensitivity in the patients was 67.9% (95% CI 60.9%–74.2%) for the satDNA OligoC-TesT and 79.1% (95% CI 72.8%–84.4%) for the kDNA OligoC-Test. Conclusions/Significance Specificities of the two T. cruzi OligoC-TesT prototypes are high on non-endemic and endemic controls. Sensitivities are moderate but significantly (p = 0.0004) higher for the kDNA OligoC-TesT compared to the satDNA OligoC-TesT. PMID:24392177

Life with the SAT: Assessing Our Young People and Our Times.

ERIC Educational Resources Information Center

Hanford, George H.

The history and nature of the Scholastic Aptitude Test (SAT) and issues that continue to be raised in the context of its use are discussed by a former president of the College Entrance Examination Board. This book provides insights into the changing role of college admissions testing since World War II; and considers the role of the SAT in…

Effects of Coaching on the Validity of the SAT: A Simulation Study.

ERIC Educational Resources Information Center

Baydar, Nazli

The effects of student coaching in preparation for the College Board Scholastic Aptitude Test (SAT) on the predictive validity of this test for freshman year performance were studied using data on 1985 freshman year students from four colleges. After the validity of the SAT was estimated for each school, a given proportion of students was picked,…

The SAT Gender Gap: Identifying the Causes.

ERIC Educational Resources Information Center

Rosser, Phyllis

Questions on the Scholastic Aptitude Test (SAT) with the largest score differences between women and men of all racial and ethnic groups were identified. Patterns of difficulty that would explain the SAT's continuing underprediction of female first-year college performance were studied. An item analysis of one form of the June 1986 SAT for 1,112…

College Math Assessment: SAT Scores vs. College Math Placement Scores

ERIC Educational Resources Information Center

Foley-Peres, Kathleen; Poirier, Dawn

2008-01-01

Many colleges and university's use SAT math scores or math placement tests to place students in the appropriate math course. This study compares the use of math placement scores and SAT scores for 188 freshman students. The student's grades and faculty observations were analyzed to determine if the SAT scores and/or college math assessment scores…

NASA Operational Simulator for Small Satellites (NOS3)

NASA Technical Reports Server (NTRS)

Zemerick, Scott

2015-01-01

The Simulation-to-Flight 1 (STF-1) CubeSat mission aims to demonstrate how legacy simulation technologies may be adapted for flexible and effective use on missions using the CubeSat platform. These technologies, named NASA Operational Simulator (NOS), have demonstrated significant value on several missions such as James Webb Space Telescope, Global Precipitation Measurement, Juno, and Deep Space Climate Observatory in the areas of software development, mission operationstraining, verification and validation (VV), test procedure development and software systems check-out. STF-1 will demonstrate a highly portable simulation and test platform that allows seamless transition of mission development artifacts to flight products. This environment will decrease development time of future CubeSat missions by lessening the dependency on hardware resources. In addition, through a partnership between NASA GSFC, the West Virginia Space Grant Consortium and West Virginia University, the STF-1 CubeSat will hosts payloads for three secondary objectives that aim to advance engineering and physical-science research in the areas of navigation systems of small satellites, provide useful data for understanding magnetosphere-ionosphere coupling and space weather, and verify the performance and durability of III-V Nitride-based materials.

Assessing Attitudes towards Statistics among Medical Students: Psychometric Properties of the Serbian Version of the Survey of Attitudes Towards Statistics (SATS)

PubMed Central

Stanisavljevic, Dejana; Trajkovic, Goran; Marinkovic, Jelena; Bukumiric, Zoran; Cirkovic, Andja; Milic, Natasa

2014-01-01

Background Medical statistics has become important and relevant for future doctors, enabling them to practice evidence based medicine. Recent studies report that students’ attitudes towards statistics play an important role in their statistics achievements. The aim of the study was to test the psychometric properties of the Serbian version of the Survey of Attitudes Towards Statistics (SATS) in order to acquire a valid instrument to measure attitudes inside the Serbian educational context. Methods The validation study was performed on a cohort of 417 medical students who were enrolled in an obligatory introductory statistics course. The SATS adaptation was based on an internationally accepted methodology for translation and cultural adaptation. Psychometric properties of the Serbian version of the SATS were analyzed through the examination of factorial structure and internal consistency. Results Most medical students held positive attitudes towards statistics. The average total SATS score was above neutral (4.3±0.8), and varied from 1.9 to 6.2. Confirmatory factor analysis validated the six-factor structure of the questionnaire (Affect, Cognitive Competence, Value, Difficulty, Interest and Effort). Values for fit indices TLI (0.940) and CFI (0.961) were above the cut-off of ≥0.90. The RMSEA value of 0.064 (0.051–0.078) was below the suggested value of ≤0.08. Cronbach’s alpha of the entire scale was 0.90, indicating scale reliability. In a multivariate regression model, self-rating of ability in mathematics and current grade point average were significantly associated with the total SATS score after adjusting for age and gender. Conclusion Present study provided the evidence for the appropriate metric properties of the Serbian version of SATS. Confirmatory factor analysis validated the six-factor structure of the scale. The SATS might be reliable and a valid instrument for identifying medical students’ attitudes towards statistics in the Serbian educational context. PMID:25405489

Assessing attitudes towards statistics among medical students: psychometric properties of the Serbian version of the Survey of Attitudes Towards Statistics (SATS).

PubMed

Stanisavljevic, Dejana; Trajkovic, Goran; Marinkovic, Jelena; Bukumiric, Zoran; Cirkovic, Andja; Milic, Natasa

2014-01-01

Medical statistics has become important and relevant for future doctors, enabling them to practice evidence based medicine. Recent studies report that students' attitudes towards statistics play an important role in their statistics achievements. The aim of the study was to test the psychometric properties of the Serbian version of the Survey of Attitudes Towards Statistics (SATS) in order to acquire a valid instrument to measure attitudes inside the Serbian educational context. The validation study was performed on a cohort of 417 medical students who were enrolled in an obligatory introductory statistics course. The SATS adaptation was based on an internationally accepted methodology for translation and cultural adaptation. Psychometric properties of the Serbian version of the SATS were analyzed through the examination of factorial structure and internal consistency. Most medical students held positive attitudes towards statistics. The average total SATS score was above neutral (4.3±0.8), and varied from 1.9 to 6.2. Confirmatory factor analysis validated the six-factor structure of the questionnaire (Affect, Cognitive Competence, Value, Difficulty, Interest and Effort). Values for fit indices TLI (0.940) and CFI (0.961) were above the cut-off of ≥0.90. The RMSEA value of 0.064 (0.051-0.078) was below the suggested value of ≤0.08. Cronbach's alpha of the entire scale was 0.90, indicating scale reliability. In a multivariate regression model, self-rating of ability in mathematics and current grade point average were significantly associated with the total SATS score after adjusting for age and gender. Present study provided the evidence for the appropriate metric properties of the Serbian version of SATS. Confirmatory factor analysis validated the six-factor structure of the scale. The SATS might be reliable and a valid instrument for identifying medical students' attitudes towards statistics in the Serbian educational context.

The End of Testing and Future Possibilities: An Examination of the Demise of SATs in England and Possible Alternative Assessments

ERIC Educational Resources Information Center

Marshall, Bethan

2008-01-01

This article looks at the controversial starting of testing, its boycott, the subsequent years of protest and, in October 2008, the apparent end of key stage examining in England. It considers a possible alternative to the tests based on a project carried out at King's College London based on portfolio assessment.

CubeSat Initiatives at KSC

NASA Technical Reports Server (NTRS)

Berg, Jared J.

2014-01-01

Even though the Small PayLoad Integrated Testing Services or SPLITS line of business is newly established, KSC has been involved in a variety of CubeSat projects and programs. CubeSat development projects have been initiated through educational outreach partnerships with schools and universities, commercial partnerships and internal training initiatives. KSC has also been involved in CubeSat deployment through programs to find launch opportunities to fly CubeSats as auxiliary payloads on previously planned missions and involvement in the development of new launch capabilities for small satellites. This overview will highlight the CubeSat accomplishments at KSC and discuss planning for future projects and opportunities.

A new tool for the assessment of satisfaction with iron chelation therapy (ICT-Sat) for patients with β-thalassemia major.

PubMed

Elalfy, Mohsen S; Massoud, Walid; Elsherif, Nayera H; Labib, Jonair H; Elalfy, Omar M; Elaasar, Safaa; von Mackensen, Sylvia

2012-06-01

High satisfaction with iron chelation is a major determinant for adherence to ICT in beta-thalassaemia major (β-TM) patients. In this study, a new tool to assess different domains of satisfaction for available forms of ICT was developed and validated. The impact of patients' satisfaction with ICT has been tested. Items were generated via focus groups and a preliminary version with 24 items (ICT-Sat) with an additional item for treatment preference and a knowledge questionnaire (KQ) was developed. 170 β-TM patients from three Thalassaemia centers in Egypt, aged 2-32 years received three questionnaires to fill in; the new ICT-Sat, a KQ, and a previously validated tool for satisfaction with ICT (SICT) and retested 4-6 weeks later to ensure re-test reliability. Type of chelation, drug related adverse events, compliance with ICT, and serum ferritin level (SF) during the year prior to the study as well as available cardiac T2*data were recorded. One hundred and fifty two β-TM patients completed all questionnaires; median age was 12 years. The final 15 remaining ICT-Sat items, yielding to four domain scores, explained 70.6% of the total variance. The "perceived effectiveness" and "fear and worries" domains of the ICT-Sat correlated significantly with the domains "perceived effectiveness" and "acceptance" of the SICT. Patients treated with oral ICT were more satisfied with perceived effectiveness, and their side effects. A new clinically based ICT-Sat tool was developed and revealed good psychometric characteristics. Adherence to ICT was better correlated with "perceived effectiveness" and SF level. Copyright © 2012 Wiley Periodicals, Inc.

Nine Facts about the SAT That Might Surprise You. Statistical Report

ERIC Educational Resources Information Center

Letukas, Lynn

2015-01-01

The purpose of this document is to identify and dispel rumors that are frequently cited about the SAT. The following is a compilation of nine popular rumors organized into three areas: "Student Demographics," "Test Preparation/Test Prediction," and "Test Utilization."

Ground Demonstration on the Autonomous Docking of Two 3U CubeSats Using a Novel Permanent-Magnet Docking Mechanism

NASA Technical Reports Server (NTRS)

Pei, Jing; Murchison, Luke; BenShabat, Adam; Stewart, Victor; Rosenthal, James; Follman, Jacob; Branchy, Mark; Sellers, Drew; Elandt, Ryan; Elliott, Sawyer;

A Multiple-Choice Mushroom: Schools, Colleges Rely More than Ever on Standardized Tests.

ERIC Educational Resources Information Center

Hawkins, B. Denise

1995-01-01

This discussion of college entrance examinations reviews differences between the Scholastic Assessment Test (SAT) and the American College Test. It then focuses on the SAT, discussing numbers of students taking the tests, changes in test construction to recognize contributions of women and minorities, involvement of African Americans in…

Electrospray Thrusters for Attitude Control of a 1-U CubeSat

NASA Astrophysics Data System (ADS)

Timilsina, Navin

With a rapid increase in the interest in use of nanosatellites in the past decade, finding a precise and low-power-consuming attitude control system for these satellites has been a real challenge. In this thesis, it is intended to design and test an electrospray thruster system that could perform the attitude control of a 1-unit CubeSat. Firstly, an experimental setup is built to calculate the conductivity of different liquids that could be used as propellants for the CubeSat. Secondly, a Time-Of-Flight experiment is performed to find out the thrust and specific impulse given by these liquids and hence selecting the optimum propellant. On the other hand, a colloidal thruster system for a 1-U CubeSat is designed in Solidworks and fabricated using Lathe and CNC Milling Machine. Afterwards, passive propellant feeding is tested in this thruster system. Finally, the electronic circuit and wireless control system necessary to remotely control the CubeSat is designed and the final testing is performed. Among the propellants studied, Ethyl ammonium nitrate (EAN) was selected as the best propellant for the CubeSat. Theoretical design and fabrication of the thruster system was performed successfully and so was the passive propellant feeding test. The satellite was assembled for the final experiment but unfortunately the microcontroller broke down during the first test and no promising results were found out. However, after proving that one thruster works with passive feeding, it could be said that the ACS testing would have worked if we had performed vacuum compatibility tests for other components beforehand.

Comparing State SAT Scores: Problems, Biases, and Corrections.

ERIC Educational Resources Information Center

Gohmann, Stephen F.

1988-01-01

One method to correct for selection bias in comparing Scholastic Aptitude Test (SAT) scores among states is presented, which is a modification of J. J. Heckman's Selection Bias Correction (1976, 1979). Empirical results suggest that sample selection bias is present in SAT score regressions. (SLD)

Pathfinder Technology Demonstrator: GlobalStar Testing and Results

NASA Technical Reports Server (NTRS)

Kuroda, Vanessa; Limes, Gregory L.; Han, Shi Lei; Hanson, John Eric; Christa, Scott E.

2016-01-01

The communications subsystem of a spacecraft is typically a SWaP (size, weight, and power) intensive subsystem in a SWaP constrained environment such as a CubeSat. Use of a satellite-based communication system, such as GlobalStars duplex GSP-1720 radio is a low SWaP potentially game-changing low-cost communication subsystem solution that was evaluated for feasibility for the NASA Pathfinder Technology Demonstrator (PTD) project. The PTD project is a series of 6U CubeSat missions to flight demonstrate and characterize novel small satellite payloads in low Earth orbit. GlobalStar is a low Earth orbit satellite constellation for satellite phone and low-speed data communications, and the GSP-1720 is their single board duplex radio most commonly used in satellite phones and shipment tracking devices. The PTD project tested the GSP-1720 to characterize its viability for flight using NASA GEVS (General Environmental Verification Standard) vibration and thermal vacuum levels, as well as testing the uplink-downlink connectivity, data throughput, and file transfer capabilities. This presentation will present the results of the environmental and capability testing of the GSP-1720 performed at NASA Ames Research Center, as well as the viability for CubeSat use in LEO.

The COLD-SAT Experiment for Cryogenic Fluid Management Technology

NASA Technical Reports Server (NTRS)

Schuster, J. R.; Wachter, J. P.; Vento, D. M.

1990-01-01

Future national space transportation missions will depend on the use of cryogenic fluid management technology development needs for these missions. In-space testing will be conducted in order to show low gravity cryogenic fluid management concepts and to acquire a technical data base. Liquid H2 is the preferred test fluid due to its propellant use. The design of COLD-SAT (Cryogenic On-orbit Liquid Depot Storage, Acquisition, and Transfer Satellite), an Expendable Launch Vehicle (ELV) launched orbital spacecraft that will perform subcritical liquid H2 storage and transfer experiments under low gravity conditions is studied. An Atlas launch vehicle will place COLD-SAT into a circular orbit, and the 3-axis controlled spacecraft bus will provide electric power, experiment control, and data management, attitude control, and propulsive accelerations for the experiments. Low levels of acceleration will provide data on the effects that low gravity might have on the heat and mass transfer processes used. The experiment module will contain 3 liquid H2 tanks; fluid transfer, pressurization and venting equipment; and instrumentation.

Steam Oxidation of FeCrAl and SiC in the Severe Accident Test Station (SATS)

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

Pint, Bruce A.; Unocic, Kinga A.; Terrani, Kurt A.

2015-08-01

Numerous research projects are directed towards developing accident tolerant fuel (ATF) concepts that will enhance safety margins in light water reactors (LWR) during severe accident scenarios. In the U.S. program, the high temperature steam oxidation performance of ATF solutions has been evaluated in the Severe Accident Test Station (SATS) at Oak Ridge National Laboratory (ORNL) since 2012 [1-3] and this facility continues to support those efforts in the ATF community. Compared to the current UO2/Zr-based alloy fuel system, alternative cladding materials can offer slower oxidation kinetics and a smaller enthalpy of oxidation that can significantly reduce the rate of heatmore » and hydrogen generation in the core during a coolant-limited severe accident [4-5]. Thus, steam oxidation behavior is a key aspect of the evaluation of ATF concepts. This report summarizes recent work to measure steam oxidation kinetics of FeCrAl and SiC specimens in the SATS.« less

Innovative power management, attitude determination and control tile for CubeSat standard NanoSatellites

NASA Astrophysics Data System (ADS)

Ali, Anwar; Mughal, M. Rizwan; Ali, Haider; Reyneri, Leonardo

2014-03-01

Electric power supply (EPS) and attitude determination and control subsystem (ADCS) are the most essential elements of any aerospace mission. Efficient EPS and precise ADCS are the core of any spacecraft mission. So keeping in mind their importance, they have been integrated and developed on a single tile called CubePMT module. Modular power management tiles (PMTs) are already available in the market but they are less efficient, heavier in weight, consume more power and contain less number of subsystems. Commercial of the shelf (COTS) components have been used for CubePMT implementation which are low cost and easily available from the market. CubePMT is developed on the design approach of AraMiS architecture: a project developed at Politecnico di Torino that provides low cost and higher performance space missions with dimensions larger than CubeSats. The feature of AraMiS design approach is its modularity. These modules can be reused for multiple missions which helps in significant reduction of the overall budget, development and testing time. One has just to reassemble the required subsystems to achieve the targeted specific mission.

PhoneSat: Ground Testing of a Phone-Based Prototype Bus

NASA Technical Reports Server (NTRS)

Felix, Carmen; Howard, Benjamin; Reyes, Matthew; Snarskiy, Fedor; Hickman, Ryan; Boshuizen, Christopher; Marshall, William

2010-01-01

Most of the key capabilities that are requisite of a satellite bus are housed in today's smart phones. PhoneSat refers to an initiative to build a ground-based prototype vehicle that could all the basic functionality of a satellite, including attitude control, using a smart Phone as its central hardware. All components used were also low cost Commercial off the Shelf (COTS). In summer 2009, an initial prototype was created using the LEGO Mindstorm toolkit demonstrating simple attitude control. Here we report on a follow up initiative to design, build and test a vehicle based on the Google s smart phone Nexus One. The report includes results from initial thermal-vacuum chamber tests and low altitude sub-orbital rocket flights which show that, at least for short durations, the Nexus One phone is able to withstand key aspects of the space environment without failure. We compare the sensor data from the Phone's accelerometers and magnetometers with that of an external microelectronic inertial measurement unit.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044916 (11 Feb. 2014) --- A set of NanoRacks CubeSats is photographed by an Expedition 38 crew member after the deployment by the Small Satellite Orbital Deployer (SSOD). The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

TechEdSat Nano-Satellite Series Fact Sheet

NASA Technical Reports Server (NTRS)

Murbach, Marcus; Martinez, Andres; Guarneros Luna, Ali

2014-01-01

TechEdSat-3p is the second generation in the TechEdSat-X series. The TechEdSat Series uses the CubeSat standards established by the California Polytechnic State University Cal Poly), San Luis Obispo. With typical blocks being constructed from 1-unit (1U 10x10x10 cm) increments, the TechEdSat-3p has a 3U volume with a 30 cm length. The project uniquely pairs advanced university students with NASA researchers in a rapid design-to-flight experience lasting 1-2 semesters.The TechEdSat Nano-Satellite Series provides a rapid platform for testing technologies for future NASA Earth and planetary missions, as well as providing students with an early exposure to flight hardware development and management.

Illustrating economic evaluation of diagnostic technologies: comparing Helicobacter pylori screening strategies in prevention of gastric cancer in Canada.

PubMed

Xie, Feng; O'Reilly, Daria; Ferrusi, Ilia L; Blackhouse, Gord; Bowen, James M; Tarride, Jean-Eric; Goeree, Ron

2009-05-01

The aim of this paper is to present an economic evaluation of diagnostic technologies using Helicobacter pylori screening strategies for the prevention of gastric cancer as an illustration. A Markov model was constructed to compare the lifetime cost and effectiveness of 4 potential strategies: no screening, the serology test by enzyme-linked immunosorbent assay (ELISA), the stool antigen test (SAT), and the (13)C-urea breath test (UBT) for the detection of H. pylori among a hypothetical cohort of 10,000 Canadian men aged 35 years. Special parameter consideration included the sensitivity and specificity of each screening strategy, which determined the model structure and treatment regimen. The primary outcome measured was the incremental cost-effectiveness ratio between the screening strategies and the no-screening strategy. Base-case analysis and probabilistic sensitivity analysis were performed using the point estimates of the parameters and Monte Carlo simulations, respectively. Compared with the no-screening strategy in the base-case analysis, the incremental cost-effectiveness ratio was $33,000 per quality-adjusted life-year (QALY) for the ELISA, $29,800 per QALY for the SAT, and $50,400 per QALY for the UBT. The probabilistic sensitivity analysis revealed that the no-screening strategy was more cost effective if the willingness to pay (WTP) was <$20,000 per QALY, while the SAT had the highest probability of being cost effective if the WTP was >$30,000 per QALY. Both the ELISA and the UBT were not cost-effective strategies over a wide range of WTP values. Although the UBT had the highest sensitivity and specificity, either no screening or the SAT could be the most cost-effective strategy depending on the WTP threshold values from an economic perspective. This highlights the importance of economic evaluations of diagnostic technologies.

So, Your Children Are College Bound ... but Are They SAT Ready? Parents Play a Key Role in Preparing Students to Standardized Tests, Experts Agree

ERIC Educational Resources Information Center

Keels, Crystal L.

2004-01-01

Parents are an essential component in their children's SAT success, says Starlett Craig, director of outreach and enrichment programs at Clemson University in South Carolina. Clemson is home to a successful two-week SAT summer camp, where students are immersed in workshops that prepare them for the exam. But whether a child goes to a SAT camp or…

Brucellosis as a neglected disease in a neglected population: a seroepidemiological study of migratory nomads in the Fars province of Iran.

PubMed

Honarvar, B; Moghadami, M; Lankarani, K B; Davarpanah, M A; Ataolahi, M; Farbod, A; Eskandari, E; Panahi, M; Ghorbani, A; Zahiri, Z; Tabrizi, R; Pourjafar, M; Heidari, S M M

2017-02-01

This study assessed the seroprevalence of brucellosis and its risk factors in migratory nomads in the Fars province of Iran. Active brucellosis was defined as the combination of clinical symptoms, including fever, chills, night sweats, headache, low back pain, arthralgia, or myalgia, and positive laboratory testing, including either a serum agglutination test (SAT) ⩾1:80 with a 2-mercaptoethanol (2-ME) test ⩾1:40, or a SAT <1:80 combined with a positive Coombs Wright test (CWT) at a titre of at least threefold higher than SAT titre results. For the 536 participants, the female (316, 59%) to male (220, 41%) ratio was 1·4 and the participants' mean age was 32·4 ± 18·9 (range 1-96) years. Of all participants, 325 (60·6%) showed clinical symptoms; in symptomatic participants, the Rose Bengal plate test was positive in 33 (6·1%) cases, the SAT was positive in 18 (3·3%) cases, and the 2-ME test was positive in 30 (5·5%) cases. Positive SAT and 2-ME results were seen in 18 (3·3%) cases, but a negative SAT and a positive CWT were found in 36 (6·7%) cases. As a result, active brucellosis was detected in 54 cases, indicating a prevalence of 10% (95% confidence interval 8-12). In conclusion, we determined that brucellosis is a prevalent yet neglected disease in this nomadic population. Brucellosis control is not possible as long as these high-risk populations remain neglected.

Computer as a Tool in SAT Preparation.

ERIC Educational Resources Information Center

Coffin, Gregory C.

Two experimental programs, designed to increase Scholastic Aptitude Test (SAT) scores of inner city, low achieving students by using computer-assisted SAT preparation, produced differing results. Forty volunteers from a nearby high school were assigned to two groups of 20 each--one experimental and one control group. The first program provided six…

Preparing Students for College Admissions Tests

ERIC Educational Resources Information Center

Appelrouth, Jed I.; Zabrucky, Karen M.; Moore, DeWayne

2017-01-01

Attaining successful outcomes on the SAT can have profound educational and financial consequences for college-bound students. Using archival data from a private tutoring centre, we investigated variables we hypothesised to contribute to SAT score increases. Our analyses revealed significant effects of time on task and rate of SAT homework…

Seroprevalence of Brucella antibodies in camels in Katsina State, Nigeria.

PubMed

Salisu, U S; Kudi, C A; Bale, J O O; Babashani, M; Kaltungo, B Y; Saidu, S N A; Asambe, A; Baba, A Y

2017-06-01

A cross-sectional study was carried out to determine the status of Brucella infection in one-humped (Dromedary) camels in the North and Central senatorial districts of Katsina State, Nigeria. Nine hundred and eighty serum samples from live and slaughtered camels were tested. Modified Rose Bengal plate test (RBPT) and serum agglutination test (SAT) with ethylenediaminetetraacetic acid, (EDTA) were used as screening and standard tests, respectively. The prevalence of Brucella antibodies were 110 (11.2%) and 103 (10.5%) for RBPT and SAT, respectively. Of the 472 and 508 serum samples tested from the herds and abattoirs, respectively, 63 (13.3%) and 47 (9.3%) were positive by RBPT while 62 (13.1%) and 41 (8.1%) were positive by SAT, respectively. Based on the results, it was concluded that Brucella antibodies were present in camels in the study area. Poor management practices and mixing of camels with other species of livestock as well as unrestricted movement of camels were proposed to be the reasons for the prevalence of the disease in the study area. In view of the public health importance of the disease, it is recommended that there is the need to develop a strategic plan to decrease spread of brucellosis in the study area.

Carbon dioxide stimulation of photosynthesis in Liquidambar styraciflua is not sustained during a 12-year field experiment

DOE PAGES

Warren, Jeffrey M.; Jensen, Anna M.; Medlyn, Belinda E.; ...

2014-11-17

Elevated atmospheric CO 2 (eCO 2) often increases photosynthetic CO 2 assimilation (A) in field studies of temperate tree species, although there is evidence that the increases may decline through time due to biochemical and morphological acclimation, and environmental constraints. Indeed, at the free air CO 2 enrichment (FACE) study in Oak Ridge, Tennessee, A was increased in 12-year-old sweetgum trees following two years of ~40% enhancement of CO 2. A was re-assessed a decade later to determine if initial enhancement of eCO 2 was sustained through time. Measurements were conducted at prevailing CO 2 and temperature on detached, re-hydratedmore » branches using a portable gas exchange system. Photosynthetic CO 2 response curves (A versus the CO 2 concentration in the intercellular air space (C i); or A-C i curves) were contrasted with earlier measurements using consistent leaf photosynthesis model equations. We accessed relationships between light-saturated photosynthesis (A sat), maximum electron transport rate (J max), maximum Rubisco activity (V cmax) chlorophyll content and foliar nitrogen (N) and chlorophyll content. In 1999, light-saturated photosynthesis (A sat) for eCO 2 treatments was 15.4 ± 0.8 μmol m -2 s -1, 22% higher than aCO 2 treatments (P<0.01). By 2009, A sat declined to <50% of 1999 values, and there was no longer a significant effect of eCO 2 (A sat = 6.9 or 5.7 ± 0.7 μmol m -2 s -1 for eCO 2 or aCO 2, respectively). In 1999, there was no treatment effect on area-based foliar N; however, by 2008, N content in eCO 2 foliage was 17% less than in aCO 2 foliage. Photosynthetic N use efficiency (A sat:N) was greater in eCO 2 in 1999 resulting in greater A sat despite similar N content, but the enhanced efficiency in eCO 2 trees was lost as foliar N declined to sub-optimal levels. There was no treatment difference in the declining linear relationships between J max or V cmax with declining N, or in the ratio of J max:V cmax through time. Results suggest that initial enhancement of photosynthesis to elevated CO 2 will not be sustained through time if nitrogen becomes limited.« less

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

Warren, Jeffrey M.; Jensen, Anna M.; Medlyn, Belinda E.

Elevated atmospheric CO 2 (eCO 2) often increases photosynthetic CO 2 assimilation (A) in field studies of temperate tree species, although there is evidence that the increases may decline through time due to biochemical and morphological acclimation, and environmental constraints. Indeed, at the free air CO 2 enrichment (FACE) study in Oak Ridge, Tennessee, A was increased in 12-year-old sweetgum trees following two years of ~40% enhancement of CO 2. A was re-assessed a decade later to determine if initial enhancement of eCO 2 was sustained through time. Measurements were conducted at prevailing CO 2 and temperature on detached, re-hydratedmore » branches using a portable gas exchange system. Photosynthetic CO 2 response curves (A versus the CO 2 concentration in the intercellular air space (C i); or A-C i curves) were contrasted with earlier measurements using consistent leaf photosynthesis model equations. We accessed relationships between light-saturated photosynthesis (A sat), maximum electron transport rate (J max), maximum Rubisco activity (V cmax) chlorophyll content and foliar nitrogen (N) and chlorophyll content. In 1999, light-saturated photosynthesis (A sat) for eCO 2 treatments was 15.4 ± 0.8 μmol m -2 s -1, 22% higher than aCO 2 treatments (P<0.01). By 2009, A sat declined to <50% of 1999 values, and there was no longer a significant effect of eCO 2 (A sat = 6.9 or 5.7 ± 0.7 μmol m -2 s -1 for eCO 2 or aCO 2, respectively). In 1999, there was no treatment effect on area-based foliar N; however, by 2008, N content in eCO 2 foliage was 17% less than in aCO 2 foliage. Photosynthetic N use efficiency (A sat:N) was greater in eCO 2 in 1999 resulting in greater A sat despite similar N content, but the enhanced efficiency in eCO 2 trees was lost as foliar N declined to sub-optimal levels. There was no treatment difference in the declining linear relationships between J max or V cmax with declining N, or in the ratio of J max:V cmax through time. Results suggest that initial enhancement of photosynthesis to elevated CO 2 will not be sustained through time if nitrogen becomes limited.« less

A Comparison of Standardized Achievement Test Scores on Right and Left Brain Dominant Fourth-Grade Students.

ERIC Educational Resources Information Center

Bell, Michael L.; Roubinek, Darrell L.

1989-01-01

Compares fourth-graders' subtest scores on the Stanford Achievement Test (SAT), the Iowa Test of Basic Skills (ITBS), and the Metropolitan Achievement Test (MAT). Finds right-brain dominant students scored better on four SAT subtests, and left-brain dominant students scored better on four ITBS subtests and two MAT subtests. (NH)

Characterization of Orbital Debris via Hyper-Velocity Laboratory-Based Tests

NASA Technical Reports Server (NTRS)

Cowardin, Heather; Liou, J.-C.; Anz-Meador, Phillip; Sorge, Marlon; Opiela, John; Fitz-Coy, Norman; Huynh, Tom; Krisko, Paula

2017-01-01

Existing DOD and NASA satellite breakup models are based on a key laboratory test, Satellite Orbital debris Characterization Impact Test (SOCIT), which has supported many applications and matched on-orbit events involving older satellite designs reasonably well over the years. In order to update and improve these models, the NASA Orbital Debris Program Office, in collaboration with the Air Force Space and Missile Systems Center, The Aerospace Corporation, and the University of Florida, replicated a hypervelocity impact using a mock-up satellite, DebriSat, in controlled laboratory conditions. DebriSat is representative of present-day LEO satellites, built with modern spacecraft materials and construction techniques. Fragments down to 2 mm in size will be characterized by their physical and derived properties. A subset of fragments will be further analyzed in laboratory radar and optical facilities to update the existing radar-based NASA Size Estimation Model (SEM) and develop a comparable optical-based SEM. A historical overview of the project, status of the characterization process, and plans for integrating the data into various models will be discussed herein.

Characterization of Orbital Debris via Hyper-Velocity Laboratory-Based Tests

NASA Technical Reports Server (NTRS)

Cowardin, Heather; Liou, J.-C.; Krisko, Paula; Opiela, John; Fitz-Coy, Norman; Sorge, Marlon; Huynh, Tom

2017-01-01

Existing DoD and NASA satellite breakup models are based on a key laboratory test, Satellite Orbital debris Characterization Impact Test (SOCIT), which has supported many applications and matched on-orbit events involving older satellite designs reasonably well over the years. In order to update and improve these models, the NASA Orbital Debris Program Office, in collaboration with the Air Force Space and Missile Systems Center, The Aerospace Corporation, and the University of Florida, replicated a hypervelocity impact using a mock-up satellite, DebriSat, in controlled laboratory conditions. DebriSat is representative of present-day LEO satellites, built with modern spacecraft materials and construction techniques. Fragments down to 2 mm in size will be characterized by their physical and derived properties. A subset of fragments will be further analyzed in laboratory radar and optical facilities to update the existing radar-based NASA Size Estimation Model (SEM) and develop a comparable optical-based SEM. A historical overview of the project, status of the characterization process, and plans for integrating the data into various models will be discussed herein.

The self-description inventory+, part 1 : factor structure and convergent validity analyses.

DOT National Transportation Integrated Search

2013-07-01

Each year the FAA hires approximately 900 new air traffic controller candidates, the majority of whom take the Air Traffic Selection and Training test battery, better known as AT-SAT. This test, developed in 1997, is based on a job/task analysis cond...

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-13

ISS038-E-046586 (13 Feb. 2014) --- A set of NanoRacks CubeSats is photographed by an Expedition 38 crew member after the deployment by the NanoRacks Launcher attached to the end of the Japanese robotic arm. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-13

ISS038-E-046579 (13 Feb. 2014) --- A set of NanoRacks CubeSats is photographed by an Expedition 38 crew member after the deployment by the NanoRacks Launcher attached to the end of the Japanese robotic arm. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

On the Factorial Structure of the SAT and Implications for Next-Generation College Readiness Assessments

ERIC Educational Resources Information Center

Wiley, Edward W.; Shavelson, Richard J.; Kurpius, Amy A.

2014-01-01

The name "SAT" has become synonymous with college admissions testing; it has been dubbed "the gold standard." Numerous studies on its reliability and predictive validity show that the SAT predicts college performance beyond high school grade point average. Surprisingly, studies of the factorial structure of the current version…

New SAT or No SAT?

ERIC Educational Resources Information Center

Malveaux, Julianne

2004-01-01

Some say the new SAT is an improved version of the old one. It adds more math, especially advanced algebra, an essay section and testing on grammar, according to some reports. Supposedly, it will rely less on rote reasoning and more on critical thinking. Will it give college admissions officers better information? Because no matter what the SAT…

Gum chewing improves adolescents’ math performance in an SAT preparatory course

USDA-ARS?s Scientific Manuscript database

The purpose of the current study was to determine the effect of gum chewing on students’ performance in a preparatory course for the Scholastic Aptitude Test (SAT). A total of 182 adolescents enrolled in an SAT preparatory class were randomized into one of two treatments: 1) gum chewing condition (G...

Spatial pattern of foot-and-mouth disease virus serotypes in North Central Nigeria

PubMed Central

Wungak, Yiltawe Simwal; Ishola, Olayinka O.; Olugasa, Babasola O.; Lazarus, David D.; Ehizibolo, David O.; Ularamu, Hussaini G.

2017-01-01

Aim: This study aimed to determine the foot-and-mouth disease virus (FMDV) serotypes circulating, the prevalence of FMDV serotypes, and the spatial distribution of FMDV among sedentary and pastoral cattle herds in the North-Central Nigeria. Materials and Methods: A cross-sectional study was undertaken, during which a total of 155 sera that tested positive for foot-and-mouth disease (FMD) 3ABC non-structural protein antibodies were selected and screened for FMD structural protein serotypes, A, O, SAT 1, and SAT 2 using a solid-phase competitive enzyme-linked immunosorbent assay (ELISA). Epithelial tissue specimens were collected during outbreak investigations which were tested for FMD using an antigen capture ELISA for serotype A, O, SAT 1, and SAT 2. Results: An overall serotype-specific prevalence of 79.35 (95% confidence interval [CI]: 72.4-85.18) was recorded for serotype O, 65.2% (95% CI: 57.41-72.3) for serotype A, 52.9% (95% CI: 45.03-60.67) for SAT 2, and 33.55% (95% CI: 26.45-41.26) for SAT 1. Evidence of exposure to multiple FMDV serotypes showed that 12.26% of the sera samples had antibodies against four serotypes circulating, 30.97% had antibodies against three serotypes circulating, 22.58% had antibodies against two serotypes, and 17% showed exposure to only one serotype. Clinical specimens (epithelial tissue) collected during outbreak investigations showed that serotype O has the highest proportion of 50% with serotype A - 25%; SAT 2 - 20.8%; and SAT 1 - 4.1%. Conclusion: The study detected diffuse and co-circulation of serotypes A, O, SAT 1, and SAT 2 within the study area, and hence the need for the appropriately matched multivalent vaccine is strongly advocated for FMD control in Nigeria. PMID:28507418

E-st@r-I experience: Valuable knowledge for improving the e-st@r-II design

NASA Astrophysics Data System (ADS)

Corpino, S.; Obiols-Rabasa, G.; Mozzillo, R.; Nichele, F.

2016-04-01

Many universities all over the world have now established hands-on education programs based on CubeSats. These small and cheap platforms are becoming more and more attractive also for other-than-educational missions, such as technology demonstration, science applications, and Earth observation. This new paradigm requires the development of adequate technology to increase CubeSat performance and mission reliability, because educationally-driven missions have often failed. In 2013 the ESA Education Office launched the Fly Your Satellite! Programme which aims at increasing CubeSat mission reliability through several actions: to improve design implementation, to define best practices for conducting the verification process, and to make the CubeSat community aware of the importance of verification. Within this framework, the CubeSat team at Politecnico di Torino developed the e-st@r-II CubeSat as follow-on of the e-st@r-I satellite, launched in 2012 on the VEGA Maiden Flight. E-st@r-I and e-st@r-II are both 1U satellites with educational and technology demonstration objectives: to give hands-on experience to university students and to test an active attitude determination and control system based on inertial and magnetic measurements with magnetic actuation. This paper describes the know-how gained thanks to the e-st@r-I mission, and how this heritage has been translated into the improvement of the new CubeSat in several areas and lifecycle phases. The CubeSat design has been reviewed to reduce the complexity of the assembly procedure and to deal with possible failures of the on-board computer, for example re-coding the software in the communications subsystem. New procedures have been designed and assessed for the verification campaign accordingly to ECSS rules and with the support of ESA specialists. Different operative modes have been implemented to handle some anomalies observed during the operations of the first satellite. A new version of the on-board software is one of the main modifications. In particular, the activation sequence of the satellite has been modified to have a stepwise switch-on of the satellite. In conclusion, the e-st@r-I experience has provided valuable lessons during its development, verification and on-orbit operations. This know-how has become crucial for the development of the e-st@r-II CubeSat as illustrated in this article.

Branded by a Test

ERIC Educational Resources Information Center

Popham, W. James

2006-01-01

Scholastic Aptitude Test (SAT) and American College Program (ACT) scores are the main determinants of college entrance in the USA. It is widely assumed that these tests are predictive of success both during college and in later life, but such views are incorrect. Another widely-held view, held by many educators, is that the SAT and ACT are…

Hispanics' SAT Scores: The Influences of Level of Parental Education, Performance-Avoidance Goals, and Knowledge about Learning

ERIC Educational Resources Information Center

Hannon, Brenda

2015-01-01

This study uncovers which learning (epistemic belief of learning), socioeconomic background (level of parental education, family income) or social-personality factors (performance-avoidance goals, test anxiety) mitigate the ethnic gap in SAT (Scholastic Assessment Test) scores. Measures assessing achievement motivation, test anxiety, socioeconomic…

The NUTS CubeSat Project: Spin-Offs and Technology Development

NASA Astrophysics Data System (ADS)

Birkeland, R.; Stein, T. A.; Tommer, M.; Beermann, B.; Petrasch, J.; Gjersvik, A.

2015-09-01

The development of CubeSats allows for the conception and implementation of new approaches and technologies. In this paper we present a spin-off and technology innovation resulting from the NTNU Test Satellite (NUTS). NUTS is a 2U CubeSat under development by students of the Norwegian University of Science and Technology (NTNU) in Trondheim, Norway. The satellite is due to launch in 2017 and is based upon in-house developments. We will describe the innovative carbon-fibre frame, radio systems and proposals for an infrared camera for atmospheric gravity waves observations. A NUTS spinoff, the Cosmic Particle Telescope (CPT-SCOPE), will be presented in greater detail since it has been selected for the BEXUS 20 campaign in autumn 2015. CPT-SCOPE is a Norwegian-German compact radiation monitor prototype developed by students.

Characterization of Orbital Debris via Hyper-Velocity Ground-Based Tests

NASA Technical Reports Server (NTRS)

Cowardin, Heather

2016-01-01

The purpose of the DebriSat project is to replicate a hyper-velocity fragmentation event using modern-day spacecraft materials and construction techniques to better improve the existing DoDand NASA breakup models.

Force Limited Vibration Testing and Subsequent Redesign of the Naval Postgraduate School CubeSat Launcher

DTIC Science & Technology

2014-06-01

release is controlled by a non-explosive actuator (NEA). Once the NEA is actuated, it releases the P-POD door, which springs open due to torsion ...deemed to be undesirable to OSL as it limited flexibility in final CubeSat position choices on NPSCuL. 24 Building on the lessons learned from the...OUTSat mission that included maintaining flexibility of CubeSat positions on NPSCuL, it was decided that the option to proto-qualify a CubeSat on the

PhoneSat - The Smartphone Nanosatellite

NASA Technical Reports Server (NTRS)

Cockrell, James J.; Yost, Bruce; Petro, Andrew

2013-01-01

NASAs PhoneSat project will test whether spacecraft can be built using smartphones to launch the lowest-cost satellites ever flown in space. Each PhoneSat nanosatellite is one cubesat unit - a satellite in a 10 cm (approx. 4 inches) cube or about the size of a tissue box - and weighs approximately three pounds. Engineers believe PhoneSat technology will enable NASA to launch multiple new satellites capable of conducting science and exploration missions at a small fraction of the cost of conventional satellites.

PhoneSat - The Smartphone Nanosatellite

NASA Technical Reports Server (NTRS)

Cockrell, James J.; Yost, Bruce; Petro, Andrew

2013-01-01

NASA's PhoneSat project tests whether spacecraft can be built using smartphones to launch the lowest-cost satellites ever flown in space. Each PhoneSat nanosatellite is one cubesat unit - a satellite in a 10 cm (approx. 4 inches) cube or about the size of a tissue box - and weighs approximately 1 kg (2.2 pounds). Engineers believe PhoneSat technology will enable NASA to launch multiple new satellites capable of conducting science and exploration missions at a small fraction of the cost of conventional satellites.

Differential Prediction Generalization in College Admissions Testing

ERIC Educational Resources Information Center

Aguinis, Herman; Culpepper, Steven A.; Pierce, Charles A.

2016-01-01

We introduce the concept of "differential prediction generalization" in the context of college admissions testing. Specifically, we assess the extent to which predicted first-year college grade point average (GPA) based on high-school grade point average (HSGPA) and SAT scores depends on a student's ethnicity and gender and whether this…

Predictions of heading date in bread wheat (Triticum aestivum L.) using QTL-based parameters of an ecophysiological model

PubMed Central

Bogard, Matthieu; Ravel, Catherine; Paux, Etienne; Bordes, Jacques; Balfourier, François; Chapman, Scott C.; Le Gouis, Jacques; Allard, Vincent

2014-01-01

Prediction of wheat phenology facilitates the selection of cultivars with specific adaptations to a particular environment. However, while QTL analysis for heading date can identify major genes controlling phenology, the results are limited to the environments and genotypes tested. Moreover, while ecophysiological models allow accurate predictions in new environments, they may require substantial phenotypic data to parameterize each genotype. Also, the model parameters are rarely related to all underlying genes, and all the possible allelic combinations that could be obtained by breeding cannot be tested with models. In this study, a QTL-based model is proposed to predict heading date in bread wheat (Triticum aestivum L.). Two parameters of an ecophysiological model (V sat and P base, representing genotype vernalization requirements and photoperiod sensitivity, respectively) were optimized for 210 genotypes grown in 10 contrasting location × sowing date combinations. Multiple linear regression models predicting V sat and P base with 11 and 12 associated genetic markers accounted for 71 and 68% of the variance of these parameters, respectively. QTL-based V sat and P base estimates were able to predict heading date of an independent validation data set (88 genotypes in six location × sowing date combinations) with a root mean square error of prediction of 5 to 8.6 days, explaining 48 to 63% of the variation for heading date. The QTL-based model proposed in this study may be used for agronomic purposes and to assist breeders in suggesting locally adapted ideotypes for wheat phenology. PMID:25148833

The cysteine synthase complex from plants. Mitochondrial serine acetyltransferase from Arabidopsis thaliana carries a bifunctional domain for catalysis and protein-protein interaction.

PubMed

Wirtz, M; Berkowitz, O; Droux, M; Hell, R

2001-02-01

Serine acetyltransferase (SAT) catalyzes the rate-limiting step of cysteine biosynthesis in bacteria and plants and functions in association with O-acetylserine (thiol) lyase (OAS-TL) in the cysteine synthase complex. Very little is known about the structure and catalysis of SATs except that they share a characteristic C-terminal hexapeptide-repeat domain with a number of enzymatically unrelated acyltransferases. Computational modeling of this domain was performed for the mitochondrial SAT isoform from Arabidopsis thaliana, based on crystal structures of bacterial acyltransferases. The results indicate a left-handed parallel beta-helix consisting of beta-sheets alternating with turns, resulting in a prism-like structure. This model was challenged by site-directed mutagenesis and tested for a suspected dual function of this domain in catalysis and hetero-oligomerization. The bifunctionality of the SAT C-terminus in transferase activity and interaction with OAS-TL is demonstrated and discussed with respect to the putative role of the cysteine synthase complex in regulation of cysteine biosynthesis.

Manufacturing Methods and Technology for Digital Fault Isolation for Printed Circuit Boards.

DTIC Science & Technology

1979-08-25

microprocessors and support chips, ROMs, RAMs, UARTs , etc. They also include rules for busses and memory testing. The special rules for test points emphasize...I 8). UART .. ...................................................... I 9). SAT...0.0 I ( 8). UART ...................................................... 0.0O S 9). SAT

Characterization of Oribtal Debris via Hyper-Velocity Ground-Based Tests

NASA Technical Reports Server (NTRS)

Cowardin, H.

2015-01-01

Existing DoD and NASA satellite breakup models are based on a key laboratory-based test, Satellite Orbital debris Characterization Impact Test (SOCIT), which has supported many applications and matched on-orbit events involving older satellite designs reasonably well over the years. In order to update and improve the break-up models and the NASA Size Estimation Model (SEM) for events involving more modern satellite designs, the NASA Orbital Debris Program Office has worked in collaboration with the University of Florida to replicate a hypervelocity impact using a satellite built with modern-day spacecraft materials and construction techniques. The spacecraft, called DebriSat, was intended to be a representative of modern LEO satellites and all major designs decisions were reviewed and approved by subject matter experts at Aerospace Corporation. DebriSat is composed of 7 major subsystems including attitude determination and control system (ADCS), command and data handling (C&DH), electrical power system (EPS), payload, propulsion, telemetry tracking and command (TT&C), and thermal management. To reduce cost, most components are emulated based on existing design of flight hardware and fabricated with the same materials. All fragments down to 2 mm is size will be characterized via material, size, shape, bulk density, and the associated data will be stored in a database for multiple users to access. Laboratory radar and optical measurements will be performed on a subset of fragments to provide a better understanding of the data products from orbital debris acquired from ground-based radars and telescopes. The resulting data analysis from DebriSat will be used to update break-up models and develop the first optical SEM in conjunction with updates into the current NASA SEM. The characterization of the fragmentation will be discussed in the subsequent presentation.

Design and Fabrication of DebriSat - A Representative LEO Satellite for Improvements to Standard Satellite Breakup Models

NASA Technical Reports Server (NTRS)

Clark, S.; Dietrich, A.; Fitz-Coy, N.; Weremeyer, M.; Liou, J.-C.

2012-01-01

This paper discusses the design and fabrication of DebriSat, a 50 kg satellite developed to be representative of a modern low Earth orbit satellite in terms of its components, materials used, and fabrication procedures. DebriSat will be the target of a future hypervelocity impact experiment to determine the physical characteristics of debris generated after an on-orbit collision of a modern LEO satellite. The major ground-based satellite impact experiment used by DoD and NASA in their development of satellite breakup models was SOCIT, conducted in 1992. The target used for that experiment was a Navy transit satellite (40 cm, 35 kg) fabricated in the 1960's. Modern satellites are very different in materials and construction techniques than those built 40 years ago. Therefore, there is a need to conduct a similar experiment using a modern target satellite to improve the fidelity of the satellite breakup models. To ensure that DebriSat is truly representative of typical LEO missions, a comprehensive study of historical LEO satellite designs and missions within the past 15 years for satellites ranging from 1 kg to 5000 kg was conducted. This study identified modern trends in hardware, material, and construction practices utilized in recent LEO missions. Although DebriSat is an engineering model, specific attention is placed on the quality, type, and quantity of the materials used in its fabrication to ensure the integrity of the outcome. With the exception of software, all other aspects of the satellite s design, fabrication, and assembly integration and testing will be as rigorous as that of an actual flight vehicle. For example, to simulate survivability of launch loads, DebriSat will be subjected to a vibration test. As well, the satellite will undergo thermal vacuum tests to verify that the components and overall systems meet typical environmental standards. Proper assembly and integration techniques will involve comprehensive joint analysis, including the precise torqueing of fasteners and thread locking. Finally, the implementation of process documentation and verification procedures is discussed to provide a comprehensive overview of the design and fabrication of this representative LEO satellite.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044887 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it deploys a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044889 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it deploys a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044890 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it deploys a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

SAT and ACT Predict College GPA after Removing "g"

ERIC Educational Resources Information Center

Coyle, Thomas R.; Pillow, David R.

2008-01-01

This research examined whether the SAT and ACT would predict college grade point average (GPA) after removing g from the tests. SAT and ACT scores and freshman GPAs were obtained from a university sample (N=161) and the 1997 National Longitudinal Study of Youth (N=8984). Structural equation modeling was used to examine relationships among g, GPA,…

CloudSat Preps for Launch at Vandenberg Air Force Base, CA

NASA Technical Reports Server (NTRS)

2005-01-01

The CloudSat spacecraft sits encapsulated within its Boeing Delta launch vehicle dual payload attach fitting at Vandenberg Air Force Base, Calif. CloudSat will share its ride to orbit late next month with NASA's CALIPSO spacecraft. The two spacecraft are designed to reveal the secrets of clouds and aerosols.

Sampling and sensitivity analyses tools (SaSAT) for computational modelling

PubMed Central

Hoare, Alexander; Regan, David G; Wilson, David P

2008-01-01

SaSAT (Sampling and Sensitivity Analysis Tools) is a user-friendly software package for applying uncertainty and sensitivity analyses to mathematical and computational models of arbitrary complexity and context. The toolbox is built in Matlab®, a numerical mathematical software package, and utilises algorithms contained in the Matlab® Statistics Toolbox. However, Matlab® is not required to use SaSAT as the software package is provided as an executable file with all the necessary supplementary files. The SaSAT package is also designed to work seamlessly with Microsoft Excel but no functionality is forfeited if that software is not available. A comprehensive suite of tools is provided to enable the following tasks to be easily performed: efficient and equitable sampling of parameter space by various methodologies; calculation of correlation coefficients; regression analysis; factor prioritisation; and graphical output of results, including response surfaces, tornado plots, and scatterplots. Use of SaSAT is exemplified by application to a simple epidemic model. To our knowledge, a number of the methods available in SaSAT for performing sensitivity analyses have not previously been used in epidemiological modelling and their usefulness in this context is demonstrated. PMID:18304361

Challenges for Serology-Based Characterization of Foot-and-Mouth Disease Outbreaks in Endemic Areas; Identification of Two Separate Lineages of Serotype O FMDV in Uganda in 2011.

PubMed

Namatovu, A; Belsham, G J; Ayebazibwe, C; Dhikusooka, M T; Wekesa, S N; Siegismund, H R; Muwanika, V B; Tjørnehøj, K

2015-10-01

Control of foot-and-mouth disease (FMD) in Uganda by ring vaccination largely depends on costly trivalent vaccines, and use of monovalent vaccines could improve the cost effectiveness. This, however, requires application of highly specific diagnostic tests. This study investigated outbreaks of FMD in seven Ugandan districts, during 2011, using the PrioCHECK® FMDV NS ELISA, solid-phase blocking ELISAs (SPBEs) and virus neutralization tests (VNTs), together with virological analyses for characterization of the responsible viruses. Two hundred and eighteen (218) cattle and 23 goat sera as well as 82 oropharyngeal fluid/epithelial tissue samples were collected. Some 50% of the cattle and 17% of the goat sera were positive by the PrioCHECK® FMDV NS ELISA, while SPBEs identified titres ≥80 for antibodies against serotype O FMD virus (FMDV) in 51% of the anti-NSP positive cattle sera. However, 35% of the anti-NSP positive cattle sera had SPBE titres ≥80 against multiple serotypes, primarily against serotypes O, SAT 1 and SAT 3. Comparison of SPBEs and VNTs for the detection of antibodies against serotypes O, SAT 1 and SAT 3 in 72 NSP positive cattle sera showed comparable results against serotype O (P = 0.181), while VNTs detected significantly fewer samples positive for antibodies against SAT 1 and SAT 3 than the SPBEs (P < 0.001). Detection of antibodies against serotype O was consistent with the isolation of serotype O FMDVs from 13 samples. Four of these viruses were sequenced and belonged to two distinct lineages within the East Africa-2 (EA-2) topotype, each differing from the currently used vaccine strain (EA-1 topotype). The relationships of these lineages to other serotype O viruses in the Eastern Africa region are discussed. To enhance the control of FMD in Uganda, there is need to improve the specificity of the SAT-SPBEs, perform vaccine matching and implement improved regional FMD control. © 2013 Blackwell Verlag GmbH.

A study of time management: the correlation between video game usage and academic performance markers.

PubMed

Anand, Vivek

2007-08-01

This study analyzes the correlation between video game usage and academic performance. Scholastic Aptitude Test (SAT) and grade-point average (GPA) scores were used to gauge academic performance. The amount of time a student spends playing video games has a negative correlation with students' GPA and SAT scores. As video game usage increases, GPA and SAT scores decrease. A chi-squared analysis found a p value for video game usage and GPA was greater than a 95% confidence level (0.005 < p < 0.01). This finding suggests that dependence exists. SAT score and video game usage also returned a p value that was significant (0.01 < p < 0.05). Chi-squared results were not significant when comparing time spent studying and an individual's SAT score. This research suggests that video games may have a detrimental effect on an individual's GPA and possibly on SAT scores. Although these results show statistical dependence, proving cause and effect remains difficult, since SAT scores represent a single test on a given day. The effects of video games maybe be cumulative; however, drawing a conclusion is difficult because SAT scores represent a measure of general knowledge. GPA versus video games is more reliable because both involve a continuous measurement of engaged activity and performance. The connection remains difficult because of the complex nature of student life and academic performance. Also, video game usage may simply be a function of specific personality types and characteristics.

Extending Clause Learning of SAT Solvers with Boolean Gröbner Bases

NASA Astrophysics Data System (ADS)

Zengler, Christoph; Küchlin, Wolfgang

We extend clause learning as performed by most modern SAT Solvers by integrating the computation of Boolean Gröbner bases into the conflict learning process. Instead of learning only one clause per conflict, we compute and learn additional binary clauses from a Gröbner basis of the current conflict. We used the Gröbner basis engine of the logic package Redlog contained in the computer algebra system Reduce to extend the SAT solver MiniSAT with Gröbner basis learning. Our approach shows a significant reduction of conflicts and a reduction of restarts and computation time on many hard problems from the SAT 2009 competition.

Sea Ice Detection Based on Differential Delay-Doppler Maps from UK TechDemoSat-1

PubMed Central

Zhu, Yongchao; Yu, Kegen; Zou, Jingui; Wickert, Jens

2017-01-01

Global Navigation Satellite System (GNSS) signals can be exploited to remotely sense atmosphere and land and ocean surface to retrieve a range of geophysical parameters. This paper proposes two new methods, termed as power-summation of differential Delay-Doppler Maps (PS-D) and pixel-number of differential Delay-Doppler Maps (PN-D), to distinguish between sea ice and sea water using differential Delay-Doppler Maps (dDDMs). PS-D and PN-D make use of power-summation and pixel-number of dDDMs, respectively, to measure the degree of difference between two DDMs so as to determine the transition state (water-water, water-ice, ice-ice and ice-water) and hence ice and water are detected. Moreover, an adaptive incoherent averaging of DDMs is employed to improve the computational efficiency. A large number of DDMs recorded by UK TechDemoSat-1 (TDS-1) over the Arctic region are used to test the proposed sea ice detection methods. Through evaluating against ground-truth measurements from the Ocean Sea Ice SAF, the proposed PS-D and PN-D methods achieve a probability of detection of 99.72% and 99.69% respectively, while the probability of false detection is 0.28% and 0.31% respectively. PMID:28704948

Carbon-14 urea breath test: does it work in patients with partial gastric resection?

PubMed

Dede, Fuat; Civen, Hüseyin; Dane, Faysal; Aliustaoglu, Mehmet; Turhal, Serdar; Turoglu, Halil Turgut; Inanir, Sabahat

2015-11-01

The diagnostic value of Carbon-14 urea breath test (C-14 UBT) in the detection of Helicobacter pylori (H. pylori) infection in non-operated patients has been proved. However, the efficacy of C-14 UBT in patients with partial gastric resection (PGR) has not been evaluated yet. Herein, the results of the C-14 UBT and H. pylori stool antigen test (HpSAT) in this patient group were compared with the endoscopic findings. Multi-breath samples C-14 UBT and HpSAT were performed in all patients on the same day. Histology was used as a gold standard for testing C-14 UBT and HpSAT diagnostic efficacies. 30 patients (mean age: 54.6 ± 11 year) with PGR were included. The sensitivity and specificity of standard C-14 UBT were 29 and 100 %, respectively. When breath samples were collected at 20th min, and >35 CPM was selected as radioactivity threshold, the sensitivity raised to 86 % without any loss of specificity. The specificity and sensitivity of the HpSAT were 71 and 96 %, respectively. The sensitivity of the standard C-14 UBT was very poor for patients with PGR, and results of HpSAT were superior in this population. Certain modifications are needed if C-14 UBT is to be used in PGR patients.

Robust optimization with transiently chaotic dynamical systems

NASA Astrophysics Data System (ADS)

Sumi, R.; Molnár, B.; Ercsey-Ravasz, M.

2014-05-01

Efficiently solving hard optimization problems has been a strong motivation for progress in analog computing. In a recent study we presented a continuous-time dynamical system for solving the NP-complete Boolean satisfiability (SAT) problem, with a one-to-one correspondence between its stable attractors and the SAT solutions. While physical implementations could offer great efficiency, the transiently chaotic dynamics raises the question of operability in the presence of noise, unavoidable on analog devices. Here we show that the probability of finding solutions is robust to noise intensities well above those present on real hardware. We also developed a cellular neural network model realizable with analog circuits, which tolerates even larger noise intensities. These methods represent an opportunity for robust and efficient physical implementations.

University of Colorado CubeSat Student Projects as Successful Model for Teaching Students about Engineering Practices

NASA Astrophysics Data System (ADS)

Palo, S. E.; Li, X.; Woods, T. N.; Kohnert, R.

2014-12-01

There is a long history of cooperation between students at the University of Colorado, Boulder and professional engineers and scientists at LASP, which has led to many successful space missions with direct student involvement. The recent student-led missions include the Student Nitric Oxide Explorer (SNOE, 1998 - 2002), the Student Dust Counter (SDC) on New Horizons (2006 - present), the Colorado Student Space Weather Experiment (CSSWE), being a very successful NSF CubeSat that launched in September 2012, and the NASA Miniature X-ray Solar Spectrometer (MinXSS) CubeSat (launch will be in early 2015). Students are involved in all aspects of the design, and they experience the full scope of the mission process from concept, to fabrication and test, and mission operations. A significant part of the student involvement in the CubeSat projects is gained by using the CubeSat development as a focal point for an existing two-semester course sequence in CU's Aerospace Engineering Sciences (AES) Department: the Space Hardware Design section of Graduate Projects I & II (ASEN 5018 & ASEN 6028). The goal of these courses is to teach graduate students how to design and build systems using a requirement-based approach and fundamental systems engineering practices. The two-semester sequence takes teams of about 15 students from requirements definition and preliminary design through manufacturing, integration, and testing. In addition to the design process, students learn key professional skills such as working effectively in groups, finding solutions to open-ended problems, and actually building a system to their own set of specifications. The partnership between AES and LASP allows us to include engineering professionals in the mix, thus more effectively training science and engineering students for future roles in the civilian or commercial space industry. The mentoring process with LASP engineers helps to mitigate risk of the inexperience of the students and ensures consistent system engineer oversight for the multi-year CubeSat programs.

Integration of a 6LilnSe 2 thermal neutron detector into a CubeSat instrument

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

Egner, Joanna C.; Groza, Michael; Burger, Arnold

This paper describes the development of a preliminary compact and lightweight neutron detection system that uses the low power consuming CubeSat platform and will be especially effective for space-based applications. This is made possible using the novel 6LiInSe 2 scintillator crystal and a silicon avalanche photodiode (Si-APD). The schematics of this instrument are presented as well as the response of the instrument to initial testing under alpha radiation. The entire system weighs 670 grams and requires 5 volts direct current at 3 watts.

Integration of a 6LilnSe 2 thermal neutron detector into a CubeSat instrument

DOE PAGES

Egner, Joanna C.; Groza, Michael; Burger, Arnold; ...

2016-11-08

This paper describes the development of a preliminary compact and lightweight neutron detection system that uses the low power consuming CubeSat platform and will be especially effective for space-based applications. This is made possible using the novel 6LiInSe 2 scintillator crystal and a silicon avalanche photodiode (Si-APD). The schematics of this instrument are presented as well as the response of the instrument to initial testing under alpha radiation. The entire system weighs 670 grams and requires 5 volts direct current at 3 watts.

Analog Approach to Constraint Satisfaction Enabled by Spin Orbit Torque Magnetic Tunnel Junctions.

PubMed

Wijesinghe, Parami; Liyanagedera, Chamika; Roy, Kaushik

2018-05-02

Boolean satisfiability (k-SAT) is an NP-complete (k ≥ 3) problem that constitute one of the hardest classes of constraint satisfaction problems. In this work, we provide a proof of concept hardware based analog k-SAT solver, that is built using Magnetic Tunnel Junctions (MTJs). The inherent physics of MTJs, enhanced by device level modifications, is harnessed here to emulate the intricate dynamics of an analog satisfiability (SAT) solver. In the presence of thermal noise, the MTJ based system can successfully solve Boolean satisfiability problems. Most importantly, our results exhibit that, the proposed MTJ based hardware SAT solver is capable of finding a solution to a significant fraction (at least 85%) of hard 3-SAT problems, within a time that has a polynomial relationship with the number of variables(<50).

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044883 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it begins the deployment of a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044994 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station prior to the deployment of a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

The Achievement Gap: Should We Rely on SAT Scores to Tell Us Anything about It?

ERIC Educational Resources Information Center

Whittington, Dale

2004-01-01

Increasing numbers of students taking the SAT have declined to identify their race/ethnicity. I examined the impact of non-respondents on the validity of reported racial/ethnic differences and year-to-year changes in test performance. Using an analysis reported by Wainer (1988) and SAT data from 1996 to 2003, I confirmed Wainer's findings that…

The SAT Prediction of Grades for Mexican-American Versus Anglo-American Students at the University of California, Riverside.

ERIC Educational Resources Information Center

Goldman, Roy D.; Richards, Regina

The predictive validity of the Scholastic Aptitude Test (SAT) for Mexican-Americans is investigated. Forty-two Mexican-American freshmen students who entered the University of California, Riverside, in the Fall 1971 participated in the study. Analyses of variance concerning ethnic groups on GPA (grade point average) and SAT verbal (SATV) and math…

Modeling the Change in PSAT Scores: A Growth Modeling Approach

ERIC Educational Resources Information Center

Himelfarb, Igor

2012-01-01

The Preliminary SAT/National Merit Scholarship Qualifying Test (PSAT/NMSQT) is a test jointly administrated by the College Board and National Merit Scholarship Corporation, which is used to prepare high school students for the SAT, and as initial screening for numerous scholarships (Marini, Mattern, & Shaw, 2011). Previous research has…

Vulnerability assessment of RC frames considering the characteristic of pulse-like ground motions

NASA Astrophysics Data System (ADS)

Xu, Chao; Wen, Zengping

2017-04-01

Pulse-like ground motions are a special class of ground motions that are particularly challenging to characterize for earthquake hazard assessment. These motions are characterized by a "pulse" in the velocity time history of the motion, and they are typically very intense and have been observed to cause severe damage to structures in past earthquakes. So it is particularly important to characterize these ground motions. Previous studies show that the severe response of structure is not entirely accounted for by measuring the intensity of the ground motion using spectral acceleration of the elastic first-mode period of a structure (Sa(T1)). This paper will use several alternative intensity measures to characterize the effect of pulse-like ground motions in vulnerability assessment. The ability of these intensity measures to characterize pulse-like ground motions will be evaluated. Pulse-like ground motions and ordinary ground motions are selected as input to carry out incremental dynamic analysis. Structural response and vulnerability are estimated by using Sa(T1) as the intensity measure. The impact of pulse period on structural response is studied through residual analysis. By comparing the difference between the structural response and vulnerability curves using pulse-like ground motions and ordinary ground motions as the input, the impact of velocity pulse on vulnerability is investigated and the shortcoming of using Sa(T1) to characterize pulse-like ground motion is analyzed. Then, vector-valued ground motion intensity measures(Sa(T1)&RT1,T2, Sa(T1)&RPGV,Sa) and inelastic displacement spectra(Sdi(T1)) are used to characterize the damage potential of pulse-like ground motions, the efficiency and sufficiency of these intensity measures are evaluated. The study shows that: have strong the damage potential of near fault ground motions with velocity pulse is closely related to the pulse period of strong motion as well as first mode period of vibration and nonlinear features of the structure. The above factors should be taken into account when choosing a reasonable ground motion parameter to characterize the damage potential of pulse-like ground motions. Vulnerability curves based on Sa(T1) show obvious differences between using near fault ground motions and ordinary ground motions, as well as pulse-like ground motions with different pulse periods as the input. When using vector-valued intensity measures such as Sa(T1)&RT1,T2, Sa(T1)&RPGV,Sa and inelastic displacement spectra, the results of vulnerability analysis are roughly the same. These ground motion intensity measures are more efficient and sufficient to characterize the damage potential of near fault ground motions with velocity pulse.

Survey on the implementation and reliability of CubeSat electrical bus interfaces

NASA Astrophysics Data System (ADS)

Bouwmeester, Jasper; Langer, Martin; Gill, Eberhard

2017-06-01

This paper provides results and conclusions on a survey on the implementation and reliability aspects of CubeSat bus interfaces, with an emphasis on the data bus and power distribution. It provides recommendations for a future CubeSat bus standard. The survey is based on a literature study and a questionnaire representing 60 launched CubeSats and 44 to be launched CubeSats. It is found that the bus interfaces are not the main driver for mission failures. However, it is concluded that the Inter Integrated Circuit (I2C) data bus, as implemented in a great majority of the CubeSats, caused some catastrophic satellite failures and a vast amount of bus lockups. The power distribution may lead to catastrophic failures if the power lines are not protected against overcurrent. A connector and wiring standard widely implemented in CubeSats is based on the PC/104 standard. Most participants find the 104 pin connector of this standard too large. For a future CubeSat bus interface standard, it is recommended to implement a reliable data bus, a power distribution with overcurrent protection and a wiring harness with smaller connectors compared with PC/104.

Micro Cathode Arc Thruster for PhoneSat: Development and Potential Applications

NASA Technical Reports Server (NTRS)

Gazulla, Oriol Tintore; Perez, Andres Dono; Agasid, Elwood; Uribe, Eddie; Trinh, Greenfield; Keidar, Michael; Teel, George; Haque, Samudra; Lukas, Joseph; Salas, Alberto Guillen;

Nursing students' attitudes toward statistics: Effect of a biostatistics course and association with examination performance.

PubMed

Kiekkas, Panagiotis; Panagiotarou, Aliki; Malja, Alvaro; Tahirai, Daniela; Zykai, Rountina; Bakalis, Nick; Stefanopoulos, Nikolaos

2015-12-01

Although statistical knowledge and skills are necessary for promoting evidence-based practice, health sciences students have expressed anxiety about statistics courses, which may hinder their learning of statistical concepts. To evaluate the effects of a biostatistics course on nursing students' attitudes toward statistics and to explore the association between these attitudes and their performance in the course examination. One-group quasi-experimental pre-test/post-test design. Undergraduate nursing students of the fifth or higher semester of studies, who attended a biostatistics course. Participants were asked to complete the pre-test and post-test forms of The Survey of Attitudes Toward Statistics (SATS)-36 scale at the beginning and end of the course respectively. Pre-test and post-test scale scores were compared, while correlations between post-test scores and participants' examination performance were estimated. Among 156 participants, post-test scores of the overall SATS-36 scale and of the Affect, Cognitive Competence, Interest and Effort components were significantly higher than pre-test ones, indicating that the course was followed by more positive attitudes toward statistics. Among 104 students who participated in the examination, higher post-test scores of the overall SATS-36 scale and of the Affect, Difficulty, Interest and Effort components were significantly but weakly correlated with higher examination performance. Students' attitudes toward statistics can be improved through appropriate biostatistics courses, while positive attitudes contribute to higher course achievements and possibly to improved statistical skills in later professional life. Copyright © 2015 Elsevier Ltd. All rights reserved.

ACT/SAT Test Preparation and Coaching Programs. What Works Clearinghouse Intervention Report

ERIC Educational Resources Information Center

What Works Clearinghouse, 2016

2016-01-01

Most colleges and universities in the United States require students to take the SAT or ACT as part of the college application process. These tests are high stakes in at least three ways. First, most universities factor scores on these tests into admissions decisions. Second, higher scores can increase a student's chances of being admitted to…

CanSat Competition: Contributing to the Development of NASA's Vision for Robotic Space Exploration

NASA Technical Reports Server (NTRS)

Berman, Joshua; Berman, Timothy; Billheimer, Thomas; Biclmer. Elizabeth; Hood, Stuart; Neas, Charles

2007-01-01

CanSat is an international student design-build-launch competition organized by the American Astronautical Society (AAS) and American Institute of Aeronautics and Astronautics (AIAA). The competition is also sponsored by the Naval Research Laboratory (NRL) and the National Aeronautics and Space Administration (NASA). The CanSat competition is designed for college, university and high school students wanting to participate in an applicable space-related competition. The objective of the CanSat competition is to complete space exploration missions by designing a specific system for a small sounding rocket payload which will follow and perform to a specific set of rules and guidelines for each year's competition. The competition encompasses a complete life-cycle of one year which includes all phases of design, integration, testing, judging and competition. The mission guidelines are based from space exploration missions and include bonus requirement options which teams may choose to participate in. The fundamental goal of the competition is to educate future engineers and scientists. This is accomplished by students applying systems engineering practices to a development project that incorporates an end-to-end life cycle, from requirements analysis, through preliminary design, integration and testing, an actual flight of the CanSat, and concluding with a post-mission debrief. This is done specifically with space related missions to bring a unique aspect of engineering and design to the competition. The competition has been progressing since its creation in 2005. The competition was originally meant to purely convey the engineering and design process to its participants, but through many experiences the competition has also undergone a learning experience with respect to systems engineering process and design. According

Electrical Power Subsystem Integration and Test for the NPS Solar Cell Array Tester CubeSat

DTIC Science & Technology

2010-12-01

Earth’s Gravitational Constant MCU Microcontroller Unit MPPT Maximum Power Point Tracker NiCr Nickel Chromium NPS Naval Postgraduate School P...new testing platform was designed, built, and used to conduct integrated testing on CubeSat Kit (CSK) compatible devices. The power budgets and...acceptance test results obtained from the testing platform were used with a solar array power generation simulation, and a battery state of charge

Strengthening of Ocean Heat Uptake Efficiency Associated with the Recent Climate Hiatus

NASA Technical Reports Server (NTRS)

Watanabe, Masahiro; Kamae, Youichi; Yoshimori, Masakazu; Oka, Akira; Sato, Makiko; Ishii, Masayoshi; Mochizuki, Takashi; Kimoto, Masahide

2013-01-01

The rate of increase of global-mean surface air temperature (SAT(sub g)) has apparently slowed during the last decade. We investigated the extent to which state-of-the-art general circulation models (GCMs) can capture this hiatus period by using multimodel ensembles of historical climate simulations. While the SAT(sub g) linear trend for the last decade is not captured by their ensemble means regardless of differences in model generation and external forcing, it is barely represented by an 11-member ensemble of a GCM, suggesting an internal origin of the hiatus associated with active heat uptake by the oceans. Besides, we found opposite changes in ocean heat uptake efficiency (k), weakening in models and strengthening in nature, which explain why the models tend to overestimate the SAT(sub g) trend. The weakening of k commonly found in GCMs seems to be an inevitable response of the climate system to global warming, suggesting the recovery from hiatus in coming decades.

Utilization of artificial recharged effluent as makeup water for industrial cooling system: corrosion and scaling.

PubMed

Wei, Liangliang; Qin, Kena; Zhao, Qingliang; Noguera, Daniel R; Xin, Ming; Liu, Chengcai; Keene, Natalie; Wang, Kun; Cui, Fuyi

2016-01-01

The secondary effluent from wastewater treatment plants was reused for industrial cooling water after pre-treatment with a laboratory-scale soil aquifer treatment (SAT) system. Up to a 95.3% removal efficiency for suspended solids (SS), 51.4% for chemical oxygen demand (COD), 32.1% for Cl(-) and 30.0% SO4(2-) were observed for the recharged secondary effluent after the SAT operation, which is essential for controlling scaling and corrosion during the cooling process. As compared to the secondary effluent, the reuse of the 1.5 m depth SAT effluent decreased the corrosion by 75.0%, in addition to a 55.1% decline of the scales/biofouling formation (with a compacted structure). The experimental results can satisfy the Chinese criterion of Design Criterion of the Industrial Circulating Cooling Water Treatment (GB 50050-95), and was more efficient than tertiary effluent which coagulated with ferric chloride. In addition, chemical structure of the scales/biofouling obtained from the cooling system was analyzed.

Intuitive Sense of Number Correlates With Math Scores on College-Entrance Examination

PubMed Central

Libertus, Melissa E.; Odic, Darko; Halberda, Justin

2012-01-01

Many educated adults possess exact mathematical abilities in addition to an approximate, intuitive sense of number, often referred to as the Approximate Number System (ANS). Here we investigate the link between ANS precision and mathematics performance in adults by testing participants on an ANS-precision test and collecting their scores on the Scholastic Aptitude Test (SAT), a standardized college-entrance exam in the USA. In two correlational studies, we found that ANS precision correlated with SAT-Quantitative (i.e., mathematics) scores. This relationship remained robust even when controlling for SAT-Verbal scores, suggesting a small but specific relationship between our primitive sense for number and formal mathematical abilities. PMID:23098904

NanoRacks CubeSat

NASA Image and Video Library

2014-02-14

ISS038-E-047232 (14 Feb. 2014) --- A set of NanoRacks CubeSats is photographed by an Expedition 38 crew member after the deployment by the NanoRacks Launcher attached to the end of the Japanese robotic arm. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing. International Space Station solar array panels provide the backdrop for the scene.

Electromagnetic Simulations for an Axisymmetric Gregorian Reflector System for a Space Deployed Inflatable Antenna

DTIC Science & Technology

2016-01-22

Q. J. Wei, S. Pan, S. Mohan, and S. Seager, Inflatable antenna for CubeSat : fabrication, deployment and results of experimental tests, 2014 IEEE...Aerospace Conference, pp. 1- 12. [8] A. Babuscia, T. Choi, C. Lee, and K-M. Cheung, Inflatable antennas and arrays for interplanetary communication using CubeSats and SmallSats, 2015 IEEE Aerospace Conference, pp. 1-9.

SAT Scores, 2012-13: Wake County Public School System (WCPSS). Measuring Up. D&A Report No. 13.22

ERIC Educational Resources Information Center

Muli, Juliana; Gilleland, Kevin; McMillen, Brad

2014-01-01

As the ACT has become part of North Carolina's mandatory testing program, SAT participation in Wake County Public School System (WCPSS) and North Carolina has declined in recent years. However, SAT performance in WCPSS remains high compared to state and national averages. In 2012-13, students in WCPSS continued to score 50-60 points higher on the…

A Historical Perspective on the Content of the SAT®. Research Report No. 2003-3. ETS RR-03-10

ERIC Educational Resources Information Center

Lawrence, Ida M.; Rigol, Gretchen W.; Van Essen, Thomas; Jackson, Carol A.

2003-01-01

This paper provides an historical perspective on the content of the SAT. The review begins at the beginning, when the first College Board SAT (the Scholastic Aptitude Test) was administered to 8,040 students on June 23, 1926. At that time, the SAT consisted of nine subtests: Definitions, Arithmetical Problems, Classification, Artificial Language,…

A Study of the Factors and Conditions Related to Changing S.A.T. Scores in a Mid-Sized Florida School District.

ERIC Educational Resources Information Center

Bullen, Nancy

1981-01-01

To determine the crucial factors affecting student performance on the Scholastic Aptitude Test (SAT) in Manatee County (Florida) public schools, researchers sent questionnaires to students who had completed the SAT in the years 1977 through 1980. Of 887 students sent the questionnaire, 188 returned responses in time for tabulation. This small…

The Relationship between SAT Scores and Retention to the Second Year: 2007 SAT Validity Sample. Statistical Report No. 2011-4

ERIC Educational Resources Information Center

Mattern, Krista D.; Patterson, Brian F.

2011-01-01

This report presents the findings from a replication of the analyses from the report, "Is Performance on the SAT Related to College Retention?" (Mattern & Patterson, 2009). The tables presented herein are based on the 2007 sample and the findings are largely the same as those presented in the original report, and show SAT scores are…

CubeSat evolution: Analyzing CubeSat capabilities for conducting science missions

NASA Astrophysics Data System (ADS)

Poghosyan, Armen; Golkar, Alessandro

2017-01-01

Traditionally, the space industry produced large and sophisticated spacecraft handcrafted by large teams of engineers and budgets within the reach of only a few large government-backed institutions. However, over the last decade, the space industry experienced an increased interest towards smaller missions and recent advances in commercial-off-the-shelf (COTS) technology miniaturization spurred the development of small spacecraft missions based on the CubeSat standard. CubeSats were initially envisioned primarily as educational tools or low cost technology demonstration platforms that could be developed and launched within one or two years. Recently, however, more advanced CubeSat missions have been developed and proposed, indicating that CubeSats clearly started to transition from being solely educational and technology demonstration platforms to offer opportunities for low-cost real science missions with potential high value in terms of science return and commercial revenue. Despite the significant progress made in CubeSat research and development over the last decade, some fundamental questions still habitually arise about the CubeSat capabilities, limitations, and ultimately about their scientific and commercial value. The main objective of this review is to evaluate the state of the art CubeSat capabilities with a special focus on advanced scientific missions and a goal of assessing the potential of CubeSat platforms as capable spacecraft. A total of over 1200 launched and proposed missions have been analyzed from various sources including peer-reviewed journal publications, conference proceedings, mission webpages as well as other publicly available satellite databases and about 130 relatively high performance missions were downselected and categorized into six groups based on the primary mission objectives including "Earth Science and Spaceborne Applications", "Deep Space Exploration", "Heliophysics: Space Weather", "Astrophysics", "Spaceborne In Situ Laboratory", and "Technology Demonstration" for in-detail analysis. Additionally, the evolution of CubeSat enabling technologies are surveyed for evaluating the current technology state of the art as well as identifying potential areas that will benefit the most from further technology developments for enabling high performance science missions based on CubeSat platforms.

SAT's Next Chapter about to Be Written

ERIC Educational Resources Information Center

Honawar, Vaishali

2005-01-01

Starting in March 2005, the SAT, taken annually by more than 1.4 million college-bound students, will undergo its most significant change since 1994, when the College Board, which sponsors the test, first allowed calculators into test rooms, added open-ended math questions, and eliminated antonyms and added more critical-reading passages in the…

The Scholastic Aptitude Test: A Response to Slack and Porter's "Critical Appraisal."

ERIC Educational Resources Information Center

Jackson, Rex

1980-01-01

Responding to allegations about the effect of coaching on the Scholastic Aptitude Test (SAT) and its predictive validity ("Harvard Educational Review," May 1980), Jackson evaluates Slack and Porter's arguments and addresses the issues of the utility of SAT scores as admissions criteria and the alleged misrepresentation of negative…

De novo generation of helper virus-satellite chimera RNAs results in disease attenuation and satellite sequence acquisition in a host-dependent manner.

PubMed

Pyle, J D; Scholthof, Karen-Beth G

2018-01-15

Panicum mosaic virus (PMV) is a helper RNA virus for satellite RNAs (satRNAs) and a satellite virus (SPMV). Here, we describe modifications that occur at the 3'-end of a satRNA of PMV, satS. Co-infections of PMV+satS result in attenuation of the disease symptoms induced by PMV alone in Brachypodium distachyon and proso millet. The 375 nt satS acquires ~100-200 nts from the 3'-end of PMV during infection and is associated with decreased abundance of the PMV RNA and capsid protein in millet. PMV-satS chimera RNAs were isolated from native infections of St. Augustinegrass and switchgrass. Phylogenetic analyses revealed that the chimeric RNAs clustered according to the host species from which they were isolated. Additionally, the chimera satRNAs acquired non-viral "linker" sequences in a host-specific manner. These results highlight the dynamic regulation of viral pathogenicity by satellites, and the selective host-dependent, sequence-based pressures for driving satRNA generation and genome compositions. Copyright © 2017 Elsevier Inc. All rights reserved.

Score Trends, SAT Validity and Subgroup Differences

ERIC Educational Resources Information Center

Camara, Wayne

2008-01-01

Presented at the Summer Institute on College Admissions at Harvard in June 2008. The presentation explores whether the SAT validity has changed with the test changes and if those changes affect specific subgroups.

Inflatable Antenna for CubeSat: Extension of the Previously Developed S-Band Design to the X-Band

NASA Technical Reports Server (NTRS)

Babuscia, Alessandra; Choi, Thomas; Cheung, Kar-Ming; Thangavelautham, Jekan; Ravichandran, Mithun; Chandra, Aman

2015-01-01

The inflatable antenna for CubeSat is a 1 meter antenna reflector designed with one side reflective Mylar, another side clear Mylar with a patch antenna at the focus. The development of this technology responds to the increasing need for more capable communication systems to allow CubeSats to operate autonomously in interplanetary missions. An initial version of the antenna for the S-Band was developed and tested in both anechoic chamber and vacuum chamber. Recent developments in transceivers and amplifiers for CubeSat at X-band motivated the extension from the S-Band to the X-Band. This paper describes the process of extending the design of the antenna to the X-Band focusing on patch antenna redesign, new manufacturing challenges and initial results of experimental tests.

Validating Standardized Testing: The Role of the SAT and ACT in Undergraduate Admissions. [Background Information to Legislative Hearing].

ERIC Educational Resources Information Center

Moore, Jamillah; Teng, Allen

A hearing was planned by the California Senate Select Committee on Higher Education Admissions and Outreach to consider the role of the Scholastic Assessment Tests (SAT) and the American College Test (ACT) in the admission of students to California's public universities. The hearing was intended to provide a serious discussion of the merits and…

An Evaluation of Kernel Equating: Parallel Equating with Classical Methods in the SAT Subject Tests[TM] Program. Research Report. ETS RR-09-06

ERIC Educational Resources Information Center

Grant, Mary C.; Zhang, Lilly; Damiano, Michele

2009-01-01

This study investigated kernel equating methods by comparing these methods to operational equatings for two tests in the SAT Subject Tests[TM] program. GENASYS (ETS, 2007) was used for all equating methods and scaled score kernel equating results were compared to Tucker, Levine observed score, chained linear, and chained equipercentile equating…

Structural Qualification Testing of the WindSat Payload Using Sine Bursts Near Structural Resonance

NASA Technical Reports Server (NTRS)

Pontius, Jim; Barnes, Donald; Broduer, Steve (Technical Monitor)

2001-01-01

Sine burst tests are often used for structural qualification of space flight hardware. In most instances, the driving frequency of the shaker is specified far below the structure's first resonant mode, such that the entire test article sees uniform acceleration. For large structures, this limits qualification testing to lower parts of the structure, or else it over-tests the lower structure to achieve qualification of the upper structure. The WindSat payload, a 10.5 foot tall graphite/epoxy, titanium, and aluminum radiometer, experiences accelerations at the six foot diameter reflector nearly four times that at the spacecraft interface. Due to size of the payload, the number of bonded joints, and the lightweight reflector support structure design and construction, using static pull testing to qualify all of the bonded joints in the upper structure would result in large, expensive, and extensive test fixturing. Sine burst testing near the first two structural resonant modes was performed on the WindSat payload to achieve the correct load factor distribution up the stack for structural qualification. In this presentation, how finite element method (FEM) sine burst predictions were used in conjunction with low level random and sine burst tests to achieve correct qualification test load factor distribution on the WindSat payload is discussed. Also presented is the risk mitigation approach for using the uncorrelated FEM in this procedure.

Reassessment of urbanization effect on surface air temperature trends at an urban station of North China

NASA Astrophysics Data System (ADS)

Bian, Tao; Ren, Guoyu

2017-11-01

Based on a homogenized data set of monthly mean temperature, minimum temperature, and maximum temperature at Shijiazhuang City Meteorological Station (Shijiazhuang station) and four rural meteorological stations selected applying a more sophisticated methodology, we reanalyzed the urbanization effects on annual, seasonal, and monthly mean surface air temperature (SAT) trends for updated time period 1960-2012 at the typical urban station in North China. The results showed that (1) urbanization effects on the long-term trends of annual mean SAT, minimum SAT, and diurnal temperature range (DTR) in the last 53 years reached 0.25, 0.47, and - 0.50 °C/decade, respectively, all statistically significant at the 0.001 confidence level, with the contributions from urbanization effects to the overall long-term trends reaching 67.8, 78.6, and 100%, respectively; (2) the urbanization effects on the trends of seasonal mean SAT, minimum SAT, and DTR were also large and statistically highly significant. Except for November and December, the urbanization effects on monthly mean SAT, minimum SAT, and DTR were also all statistically significant at the 0.05 confidence level; and (3) the annual, seasonal, and monthly mean maximum SAT series at the urban station registered a generally weaker and non-significant urbanization effect. The updated analysis evidenced that our previous work for this same urban station had underestimated the urbanization effect and its contribution to the overall changes in the SAT series. Many similar urban stations were being included in the current national and regional SAT data sets, and the results of this paper further indicated the importance and urgency for paying more attention to the urbanization bias in the monitoring and detection of global and regional SAT change based on the data sets.

Norm-Referenced Tests and Race-Blind Admissions: The Case for Eliminating the SAT and ACT at the University of California. Research & Occasional Paper Series: CSHE.15.17

ERIC Educational Resources Information Center

Geiser, Saul

2017-01-01

Of all college admission criteria, scores on nationally normed tests like the SAT and ACT are most affected by the socioeconomic background of the student. The effect of socioeconomic background on test scores has grown substantially at University of California over the past two decades, and tests have become more of a barrier to admission of…

The Dutch Brucella abortus monitoring programme for cattle: the impact of false-positive serological reactions and comparison of serological tests.

PubMed

Emmerzaal, A; de Wit, J J; Dijkstra, Th; Bakker, D; van Zijderveld, F G

2002-02-01

The Dutch national Brucella abortus eradication programme for cattle started in 1959. Sporadic cases occurred yearly until 1995; the last infected herd was culled in 1996. In August 1999 the Netherlands was declared officially free of bovine brucellosis by the European Union. Before 1999, the programme to monitor the official Brucella-free status of bovine herds was primarily based on periodical testing of dairy herds with the milk ring test (MRT) and serological testing of all animals older than 1 year of age from non-dairy herds, using the micro-agglutination test (MAT) as screening test. In addition, serum samples of cattle that aborted were tested with the MAT. The high number of false positive reactions in both tests and the serum agglutination test (SAT) and complement fixation test (CFT) used for confirmation seemed to result in unnecessary blockade of herds, subsequent testing and slaughter of animals. For this reason, a validation study was performed in which three indirect enzyme-linked immunosorbent assays (ELISAs), the CFT and the SAT were compared using a panel of sera from brucellosis-free cattle, sera from experimentally infected cattle, and sera from cattle experimentally infected with bacteria which are known to induce cross-reactive antibodies (Pasteurella, Salmonella, Yersinia, and Escherichia). Moreover, four ELISAs and the MRT were compared using a panel of 1000 bulk milk samples from Brucella-free herds and 12 milk samples from Brucella abortus- infected cattle. It is concluded that the ELISA obtained from ID-Lelystad is the most suitable test to monitor the brucelosis free status of herds because it gives rise to fewer false-positive reactions than the SAT.

A multifunctional solar panel antenna for cube satellites

NASA Astrophysics Data System (ADS)

Fawole, Olutosin C.

The basic cube satellite (CubeSat) is a modern small satellite that has a standard size of about one liter (the 1U CubeSat). Three 1U CubeSats could be stacked to form a 3U CubeSat. Their low-cost, short development time, and ease of deployment make CubeSats popular for space research, geographical information gathering, and communication applications. An antenna is a key part of the CubeSat communication subsystem. Traditionally, antennas used on CubeSats are wrapped-up wire dipole antennas, which are deployed after satellite launch. Another antenna type used on CubeSats is the patch antenna. In addition to their low gain and efficiency, deployable dipole antennas may also fail to deploy on satellite launch. On the other hand, a solid patch antenna will compete for space with solar cells when placed on a CubeSat face, interfering with satellite power generation. Slot antennas are promising alternatives to dipole and patch antennas on CubeSats. When excited, a thin slot aperture etched on a conductive sheet (ground plane) is an efficient bidirectional radiator. This open slot antenna can be backed by a reflector or cavity for unidirectional radiation, and solar cells can be placed in spaces on the ground plane not occupied by the slot. The large surface areas of 3U CubeSats can be exploited for a multifunctional antenna by integrating multiple thin slot radiators, which are backed by a thin cavity on the CubeSat surfaces. Solar cells can then be integrated on the antenna surface. Polarization diversity and frequency diversity improve the overall performance of a communication system. Having a single radiating structure that could provide these diversities is desired. It has been demonstrated that when a probe excites a square cavity with two unequal length crossed-slots, the differential radiation from the two slots combines in the far-field to yield circular polarization. In addition, it has been shown that two equal-length proximal slots, when both fed with a stripline, resonate at a frequency due to their original lengths, and also resonate at a lower frequency due to mutual coupling between the slots, leading to a dual-band operation. The multifunctional antenna designs presented are harmonizations and extensions of these two independent works. In the multifunctional antenna designs presented, multiple slots were etched on a 83 mm x 340 mm two-layer shallow cavity. The slots were laid out on the cavity such when the cavity was excited by a probe at a particular point, the differential radiation from the slots would combine in the far-field to yield Left-Handed Circular Polarization (LHCP). Furthermore, when the cavity was excited by another probe at an opposite point, the slots would produce Right-Handed Circular Polarization (RHCP). In addition, as forethought, these slots were laid out on the cavity such that some slots were close together enough to give Linearly Polarized (LP) dual-band operation when fed with a stripline. This antenna was designed and optimized via computer simulations, fabricated using Printed Circuit Board (PCB) technology, and characterized using a Vector Network Analyzer (VNA) and NSI Far Field Systems.

VZLUSAT-1: verification of new materials and technologies for space

NASA Astrophysics Data System (ADS)

Daniel, Vladimir; Urban, Martin; Nentvich, Ondrej; Stehlikova, Veronika

2016-09-01

CubeSats are a good opportunity to test new technologies and materials on orbit. These innovations can be later used for improving of properties and life length of Cubesat or other satellites as well. VZLUSAT-1 is a small satellite from the CubeSat family, which will carry a wide scale of payloads with different purposes. The poster is focused on measuring of degradation and properties measurement of new radiation hardened composite material in orbit due to space environment. Material properties changes can be studied by many methods and in many disciplines. One payload measures mechanical changes in dependence on Young's modulus of elasticity which is got from non-destructive testing by mechanical vibrations. The natural frequencies we get using Fast Fourier Transform. The material is tested also by several thermometers which measure heat distribution through the composite, as well as reflectivity in dependence on different coatings. The satellite also will measure the material radiation shielding properties. There are PIN diodes which measure the relative shielding efficiency of composite and how it will change in time in space environment. Last one of material space testing is measurement of outgassing from tested composite material. It could be very dangerous for other parts of satellite, like detectors, when anything was outgassing, for example water steam. There are several humidity sensors which are sensitive to steam and other gases and measures temperatures as well.

Some Horsesense about Raising SAT Scores.

ERIC Educational Resources Information Center

Hillje, Barbara Brown

1980-01-01

Shares some warnings and positive suggestions about preparing students for the Scholastic Aptitude Tests (SATs). Urges teachers to concentrate on improving students' reading and writing skills rather than have students memorize long lists of big words. (RL)

Modeling Tidal Stresses on Satellites Using an Enhanced SatStressGUI

NASA Astrophysics Data System (ADS)

Patthoff, D. A.; Pappalardo, R. T.; Li, J.; Ayton, B.; Kay, J.; Kattenhorn, S. A.

2015-12-01

Icy and rocky satellites of our solar system display a wide range of geological deformation on their surfaces. Some are old and heavily cratered while other are observed to be presently active. Many of the potential sources of stress which can deform satellites are tied to the tidal deformation the moons experience as they orbit their parent planets. Other plausible sources of global-scale stress include a change in orbital parameters, nonsynchronous rotation, or volume change induced by the melting or freezing of a subsurface layer. We turn to computer modeling to correlate observed geologic features to the possible stresses that created them. One model is the SatStress open-source program developed by Z. Selvans (Wahr et al.,2009) to compute viscoelastic diurnal and nonsynchronous rotation stresses using a four-layer viscoelastic satellite model. Kay and Katternhorn (2010) expanded on this work by developing SatStressGUI, which integrated SatStress's original features into a graphical user interface. SatStressGUI computes stress vectors and Love numbers, and generates stress plots and lineaments. We have expanded on SatStressGUI by adding features such as the ability to generate cycloid-style lineaments, calculate stresses resulting from obliquity, and more efficient batch the processing of data. Users may also define their own Love numbers to propagate through further calculations. Here we demonstrate our recent enhancements to SatStressGUI and its abilities, by comparing observed features on Enceladus and Europa to modeled diurnal, nonsynchronous, and obliquity stresses.

Removal of pharmaceuticals and personal care products during water recycling: microbial community structure and effects of substrate concentration.

PubMed

Onesios-Barry, Kathryn M; Berry, David; Proescher, Jody B; Sivakumar, I K Ashok; Bouwer, Edward J

2014-04-01

Many pharmaceuticals and personal care products (PPCPs) have been shown to be biotransformed in water treatment systems. However, little research exists on the effect of initial PPCP concentration on PPCP biotransformation or on the microbial communities treating impacted water. In this study, biological PPCP removal at various concentrations was assessed using laboratory columns inoculated with wastewater treatment plant effluent. Pyrosequencing was used to examine microbial communities in the columns and in soil from a soil aquifer treatment (SAT; a method of water treatment prior to reuse) site. Laboratory columns were supplied with different concentrations (0.25, 10, 100, or 1,000 μg liter(-1)) of each of 15 PPCPs. Five PPCPs (4-isopropyl-3-methylphenol [biosol], p-chloro-m-xylenol, gemfibrozil, ketoprofen, and phenytoin) were not removed at any tested concentrations. Two PPCPs (naproxen and triclosan) exhibited removals independent of PPCP concentration. PPCP removal efficiencies were dependent on initial concentrations for biphenylol, p-chloro-m-cresol, chlorophene, diclofenac, 5-fluorouracil, ibuprofen, and valproic acid, showing that PPCP concentration can affect biotransformation. Biofilms from sand samples collected from the 0.25- and 10-μg liter(-1) PPCP columns were pyrosequenced along with SAT soil samples collected on three consecutive days of a wetting and drying cycle to enable comparison of these two communities exposed to PPCPs. SAT communities were similar to column communities in taxonomy and phylotype composition, and both were found to contain close relatives of known PPCP degraders. The efficiency of biological removal of PPCPs was found to be dependent on the concentration at which the contamination occurs for some, but not all, PPCPs.

Removal of Pharmaceuticals and Personal Care Products during Water Recycling: Microbial Community Structure and Effects of Substrate Concentration

PubMed Central

Onesios-Barry, Kathryn M.; Berry, David; Proescher, Jody B.; Sivakumar, I. K. Ashok

2014-01-01

Many pharmaceuticals and personal care products (PPCPs) have been shown to be biotransformed in water treatment systems. However, little research exists on the effect of initial PPCP concentration on PPCP biotransformation or on the microbial communities treating impacted water. In this study, biological PPCP removal at various concentrations was assessed using laboratory columns inoculated with wastewater treatment plant effluent. Pyrosequencing was used to examine microbial communities in the columns and in soil from a soil aquifer treatment (SAT; a method of water treatment prior to reuse) site. Laboratory columns were supplied with different concentrations (0.25, 10, 100, or 1,000 μg liter−1) of each of 15 PPCPs. Five PPCPs (4-isopropyl-3-methylphenol [biosol], p-chloro-m-xylenol, gemfibrozil, ketoprofen, and phenytoin) were not removed at any tested concentrations. Two PPCPs (naproxen and triclosan) exhibited removals independent of PPCP concentration. PPCP removal efficiencies were dependent on initial concentrations for biphenylol, p-chloro-m-cresol, chlorophene, diclofenac, 5-fluorouracil, ibuprofen, and valproic acid, showing that PPCP concentration can affect biotransformation. Biofilms from sand samples collected from the 0.25- and 10-μg liter−1 PPCP columns were pyrosequenced along with SAT soil samples collected on three consecutive days of a wetting and drying cycle to enable comparison of these two communities exposed to PPCPs. SAT communities were similar to column communities in taxonomy and phylotype composition, and both were found to contain close relatives of known PPCP degraders. The efficiency of biological removal of PPCPs was found to be dependent on the concentration at which the contamination occurs for some, but not all, PPCPs. PMID:24509919

Unfair Treatment? The Case of Freedle, the SAT, and the Standardization Approach to Differential Item Functioning

ERIC Educational Resources Information Center

Santelices, Maria Veronica; Wilson, Mark

2010-01-01

In 2003, the "Harvard Educational Review" published a controversial article by Roy Freedle that claimed bias against African American students in the SAT college admissions test. Freedle's work stimulated national media attention and faced an onslaught of criticism from experts at the Educational Testing Service (ETS), the agency…

Race, Poverty and SAT Scores: Modeling the Influences of Family Income on Black and White High School Students' SAT Performance

ERIC Educational Resources Information Center

Dixon-Roman, Ezekiel J.; Everson, Howard T.; McArdle, John J.

2013-01-01

Background: Educational policy makers and test critics often assert that standardized test scores are strongly influenced by factors beyond individual differences in academic achievement such as family income and wealth. Unfortunately, few empirical studies consider the simultaneous and related influences of family income, parental education, and…

Who's on First? Gender Differences in Performance on the "SAT"® Test on Critical Reading Items with Sports and Science Content. Research Report. ETS RR-16-26

ERIC Educational Resources Information Center

Chubbuck, Kay; Curley, W. Edward; King, Teresa C.

2016-01-01

This study gathered quantitative and qualitative evidence concerning gender differences in performance by using critical reading material on the "SAT"® test with sports and science content. The fundamental research questions guiding the study were: If sports and science are to be included in a skills test, what kinds of material are…

CUBES Project Support

NASA Technical Reports Server (NTRS)

Jenkins, Kenneth T., Jr.

2012-01-01

CUBES stands for Creating Understanding and Broadening Education through Satellites. The goal of the project is to allow high school students to build a small satellite, or CubeSat. Merritt Island High School (MIHS) was selected to partner with NASA, and California Polytechnic State University (Cal-Poly}, to build a CubeSat. The objective of the mission is to collect flight data to better characterize maximum predicted environments inside the CubeSat launcher, Poly-Picosatellite Orbital Deplorer (P-POD), while attached to the launch vehicle. The MIHS CubeSat team will apply to the NASA CubeSat Launch Initiative, which provides opportunities for small satellite development teams to secure launch slots on upcoming expendable launch vehicle missions. The MIHS team is working to achieve a test launch, or proof of concept flight aboard a suborbital launch vehicle in early 2013.

A Combined Hazard Index Fire Test Methodology for Aircraft Cabin Materials. Volume I.

DTIC Science & Technology

1982-04-01

PROGRAM TEST PANEL NO. 1 ....... 52 5 SUMARY OF EXPERIMTAL CHAS/SATS DATA FOR CI PRGRAM TEST PANEL 2, 3 & 4...As indicated in Figure 2, the dose of each hazard building up in CHI zone 13 is approaching an "effective dose" limit which prevents occupant escape...per minute. During a test, flow into SATS was stopped when CO reached peak concentrations to prevent dilution thereafter at decreasing sample CO

Solar neutron observations with ChubuSat-2 satellite

NASA Astrophysics Data System (ADS)

Yamaoka, Kazutaka

2016-07-01

Solar neutron observation is a key in understanding of ion accerelation mechanism in the Sun surface since neutrons are hardly affected by magnetic field around the Sun and intersteller mediums unlike charged particles. However, there was only a few tenth detections so far since its discovery in 1982. Actually SEDA-AP Fiber detector (FIB) onboard the International Space Station (ISS) was suffered from a high neutron background produced by the ISS itself. ChubuSat is a series of 50-kg class microsatellite jointly depeloped by universities (Nagoya university and Daido university) and aerospace companies at the Chubu area of central Japan. The ChubuSat-2 is the second ChubuSat following the ChubuSat-1 which was launched by Russian DNEPR rocket on November 6, 2014. It was selected as one of four piggyback payloads of the X-ray astronomy satellite ASTRO-H in 2014 summer, and will be launched by the H-IIA launch vehcles from from JAXA Tanegashima Space Center (TNSC) in February 2016. The ChubuSat-2 carries a mission instrument, radiation detector (RD). The main mission of ChubuSat-2 is devoted for monitoring neutrons and gamma-rays which can be background source for ASTRO-H celestrial observations with the RD. The mission also involves a function of solar neutron observations which were originally proposed by graduate students who join the leadership development program for space exploration and research, program for leading graduate schools at Nagoya University. The RD has a similar detection area and efficiency to those of the SEDA-AP FIB, but is expected to have lower backgrounthan the ISS thanks to much smaller mass of the micro-satellite. In this paper, we will describe details of ChubuSat-2 satellite and RD, and in-orbit performance of RD.

Periodically Launched, Dedicated CubeSats/SmallSats for Space Situational Awareness Through NASA Communications Networks

NASA Astrophysics Data System (ADS)

Stromberg, E. M.; Shaw, H.; Estabrook, P.; Neilsen, T. L.; Gunther, J.; Swenson, C.; Fish, C. S.; Schaire, S. H.

2014-12-01

Space Situational Awareness (SSA) is an area where spaceflight activities and missions can directly influence the quality of life on earth. The combination of space weather, near earth orbiting objects, atmospheric conditions at the space boundary, and other phenomena can have significant short-term and long-term implications for the inhabitants of this planet. The importance of SSA has led to increased activity in this area from both space and ground based platforms. The emerging capability of CubeSats and SmallSats provides an opportunity for these low-cost, versatile platforms to augment the SSA infrastructure. The CubeSats and SmallSats can be launched opportunistically with shorter lead times than larger missions. They can be organized both as constellations or individual sensor elements. Combining CubeSats and SmallSats with the existing NASA communications networks (TDRS Space Network, Deep Space Network and the Near Earth Network) provide a backbone structure for SSA which can be tied to a SSA portal for data distribution and management. In this poster we will describe the instruments and sensors needed for CubeSat and SmallSat SSA missions. We will describe the architecture and concept of operations for a set of opportunistic, periodically launched, SSA CubeSats and SmallSats. We will also describe the integrated communications infrastructure to support end-to-end data delivery and management to a SSA portal.

Identification of Trypanosoma cruzi Discrete Typing Units (DTUs) in Latin-American migrants in Barcelona (Spain).

PubMed

Abras, Alba; Gállego, Montserrat; Muñoz, Carmen; Juiz, Natalia A; Ramírez, Juan Carlos; Cura, Carolina I; Tebar, Silvia; Fernández-Arévalo, Anna; Pinazo, María-Jesús; de la Torre, Leonardo; Posada, Elizabeth; Navarro, Ferran; Espinal, Paula; Ballart, Cristina; Portús, Montserrat; Gascón, Joaquim; Schijman, Alejandro G

2017-04-01

Trypanosoma cruzi, the causative agent of Chagas disease, is divided into six Discrete Typing Units (DTUs): TcI-TcVI. We aimed to identify T. cruzi DTUs in Latin-American migrants in the Barcelona area (Spain) and to assess different molecular typing approaches for the characterization of T. cruzi genotypes. Seventy-five peripheral blood samples were analyzed by two real-time PCR methods (qPCR) based on satellite DNA (SatDNA) and kinetoplastid DNA (kDNA). The 20 samples testing positive in both methods, all belonging to Bolivian individuals, were submitted to DTU characterization using two PCR-based flowcharts: multiplex qPCR using TaqMan probes (MTq-PCR), and conventional PCR. These samples were also studied by sequencing the SatDNA and classified as type I (TcI/III), type II (TcII/IV) and type I/II hybrid (TcV/VI). Ten out of the 20 samples gave positive results in the flowcharts: TcV (5 samples), TcII/V/VI (3) and mixed infections by TcV plus TcII (1) and TcV plus TcII/VI (1). By SatDNA sequencing, we classified the 20 samples, 19 as type I/II and one as type I. The most frequent DTU identified by both flowcharts, and suggested by SatDNA sequencing in the remaining samples with low parasitic loads, TcV, is common in Bolivia and predominant in peripheral blood. The mixed infection by TcV-TcII was detected for the first time simultaneously in Bolivian migrants. PCR-based flowcharts are very useful to characterize DTUs during acute infection. SatDNA sequence analysis cannot discriminate T. cruzi populations at the level of a single DTU but it enabled us to increase the number of characterized cases in chronically infected patients. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

PhoneSat 2.4 Launches to Orbit aboard Minotaur-1 Rocket (Reporter Package)

NASA Image and Video Library

2013-11-21

On November 19, NASA's PhoneSat 2.4 successfully launched into space on board a Minotaur-1 rocket from the Wallops Flight Facility in Virginia. Built at NASA's Ames Research Center, the smartphone-based cubesat is an improved version of the previous PhoneSat satellites.

NASA Near Earth Network (NEN) Support for Lunar and L1/L2 CubeSats

NASA Technical Reports Server (NTRS)

Schaire, Scott; Altunc, Serhat; Wong, Yen; Shelton, Marta; Celeste, Peter; Anderson, Michael; Perrotto, Trish

2017-01-01

The NASA Near Earth Network (NEN) consists of globally distributed tracking stations, including NASA, commercial, and partner ground stations, that are strategically located to maximize the coverage provided to a variety of orbital and suborbital missions, including those in LEO, GEO, HEO, lunar and L1/L2 orbits. The NENs future mission set includes and will continue to include CubeSat missions. The majority of the CubeSat missions destined to fly on EM-1, launching in late 2018, many in a lunar orbit, will communicate with ground based stations via X-band and will utilize the NASA Jet Propulsion Laboratory (JPL) developed IRIS radio. The NEN recognizes the important role CubeSats are beginning to play in carrying out NASAs mission and is therefore investigating the modifications needed to provide IRIS radio compatibility. With modification, the NEN could potentially expand support to the EM-1 lunar CubeSats.The NEN could begin providing significant coverage to lunar CubeSat missions utilizing three to four of the NENs mid-latitude sites. This coverage would supplement coverage provided by the JPL Deep Space Network (DSN). The NEN, with smaller apertures than DSN, provides the benefit of a larger beamwidth that could be beneficial in the event of uncertain ephemeris data. In order to realize these benefits the NEN would need to upgrade stations targeted based on coverage ability and current configuration/ease of upgrade, to ensure compatibility with the IRIS radio. In addition, the NEN is working with CubeSat radio developers to ensure NEN compatibility with alternative CubeSat radios for Lunar and L1/L2 CubeSats. The NEN has provided NEN compatibility requirements to several radio developers who are developing radios that offer lower cost and, in some cases, more capabilities with fewer constraints. The NEN is ready to begin supporting CubeSat missions. The NEN is considering network upgrades to broaden the types of CubeSat missions that can be supported and is supporting both the CubeSat community and radio developers to ensure future CubeSat missions have multiple options when choosing a network for their communications support.

Conservatism and Cognitive Ability

ERIC Educational Resources Information Center

Stankov, Lazar

2009-01-01

Conservatism and cognitive ability are negatively correlated. The evidence is based on 1254 community college students and 1600 foreign students seeking entry to United States' universities. At the individual level of analysis, conservatism scores correlate negatively with SAT, Vocabulary, and Analogy test scores. At the national level of…

Arctic and Antarctic Sea-Ice Freeboard and Thickness Retrievals from CryoSat-2 and EnviSat

NASA Astrophysics Data System (ADS)

Ricker, Robert; Hendricks, Stefan; Schwegmann, Sandra; Helm, Veit; Rinne, Eero

2016-04-01

The CryoSat-2 satellite is now in the 6th year of data acquisition. With its synthetic aperture radar altimeter, CryoSat-2 achieves great improvements in the along track resolution compared to previous radar altimeter missions like ERS or Envisat. The latitudinal coverage contains major parts of the Arctic marine ice fields where previous missions left a big data gap around the North Pole and especially over the multiyear ice zone north of Greenland. With this unique data set, changes in sea-ice thickness can be investigated in the context of the rapid reduction of the Arctic sea-ice cover which has been observed during the last decades. We present the current state of the CryoSat-2 Arctic sea-ice thickness retrieval that is processed at the Alfred Wegener Institute and available via seaiceportal.de (originally: meereisportal.de). Though biases in sea-ice thickness may occur due to the interpretation of waveforms, airborne and ground-based validation measurements give confidence that the retrieval algorithm enables us to capture the actual distributions of sea-ice regimes. Nevertheless, long time series of data retrievals are essential to estimate trends in sea-ice thickness and volume. Today, more than 20 years of radar altimeter data are potentially available and capable to derive sea ice thickness. However, data originate from satellites with different sensor characteristics. Therefore, it is crucial to study the consistency between single sensors to derive long and consistent time series. We present results from the tested consistency between Antarctic freeboard measurements of the radar altimeters on-board of Envisat and CryoSat-2 for their overlap period in 2011.

Rapid diagnosis of pulmonary tuberculosis and detection of drug resistance by combined simultaneous amplification testing and reverse dot blot.

PubMed

Chen, Yiwen; Zhang, Lahong; Hong, Liquan; Luo, Xian; Chen, Juping; Tang, Leiming; Chen, Jiahuan; Liu, Xia; Chen, Zhaojun

2018-06-01

Making a correct and rapid diagnosis is essential for managing pulmonary tuberculosis (PTB), particularly multidrug-resistant tuberculosis. We aimed to evaluate the efficacy of the combination of simultaneous amplification testing (SAT) and reverse dot blot (RDB) for the rapid detection of Mycobacterium tuberculosis (MTB) and drug-resistant mutants in respiratory samples. 225 suspected PTB and 32 non-TB pulmonary disease samples were collected. All sputum samples were sent for acid-fast bacilli smear, SAT, culture and drug susceptibility testing (DST) by the BACTEC TM MGIT TM 960 system. 53 PTB samples were tested by both RDB and DNA sequencing to identify drug resistance genes and mutated sites. The SAT positive rate (64.9%) was higher than the culture positive rate (55.1%), with a coincidence rate of 83.7%. The sensitivity and specificity of SAT for diagnosing PTB were 66.7% and 100%, respectively, while those for culture were 53.9% and 84.2%, respectively. RDB has high sensitivity and specificity in identifying drug resistance genes and mutated sites. The results of RDB correlated well with those of DST and DNA sequencing, with coincidence rates of 92.5% and 98.1%, respectively. The combination of SAT and RDB is promising for rapidly detecting PTB and monitoring drug resistance in clinical laboratories. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Malaria Early Warning: The MalarSat project

NASA Astrophysics Data System (ADS)

Roca, M.; Escorihuela, M. J.; Martínez, D.; Torrent, M.; Aponte, J.; Nunez, F.; Garcia, J.

2009-04-01

Malaria is one of the major public health challenges undermining development in the world. The aim of MalarSat Project is to provide a malaria risks infection maps at global scale using Earth Observation data to support and prevent epidemic episodes. The proposed service for creating malaria risk maps would be critically useful to improve the efficiency in insecticide programs, vaccine campaigns and the logistics epidemic treatment. Different teams have already carried out studies in order to exploit the use of Earth Observation (EO) data with epidemiology purposes. In the case of malaria risk maps, it has been shown that meteorological data is not sufficient to fulfill this objective. In particular being able to map the malaria mosquito habitat would increase the accuracy of risk maps. The malaria mosquitoes mainly reproduce in new water puddles of very reduced dimensions (about 1 meter wide). There is no instrument that could detect such small patches of water unless there are many of them spread in an area of several hundreds of meters. MalarSat aims at using the radar altimeter data from the EnviSat, RA-2, to try and build indicators of mosquitoes existence. This presentation will show the scientific objectives and principles of the MalarSat project.

Development of a Solar Array Drive Assembly for CubeSat

NASA Technical Reports Server (NTRS)

Passaretti, Mike; Hayes, Ron

2010-01-01

Small satellites and in particular CubeSats, have increasingly become more viable as platforms for payloads typically requiring much larger bus structures. As advances in technology make payloads and instruments for space missions smaller, lighter and more power efficient, a niche market is emerging from the university community to perform rapidly developed, low-cost missions on very small spacecraft - micro, nano, and picosatellites. In just the last few years, imaging, biological and new technology demonstration missions have been either proposed or have flown using variations of the CubeSat structure as a basis. As these missions have become more complex, and the CubeSat standard has increased in both size (number of cubes) and mass, available power has become an issue. Body-mounted solar cells provide a minimal amount of power; deployable arrays improve on that baseline but are still limited. To truly achieve maximum power, deployed tracked arrays are necessary. To this end, Honeybee Robotics Spacecraft Mechanisms Corporation, along with MMA of Nederland Colorado, has developed a solar array drive assembly (SADA) and deployable solar arrays specifically for CubeSat missions. In this paper, we discuss the development of the SADA.

A Glimpse into the Satellite DNA Library in Characidae Fish (Teleostei, Characiformes)

PubMed Central

Utsunomia, Ricardo; Ruiz-Ruano, Francisco J.; Silva, Duílio M. Z. A.; Serrano, Érica A.; Rosa, Ivana F.; Scudeler, Patrícia E. S.; Hashimoto, Diogo T.; Oliveira, Claudio; Camacho, Juan Pedro M.; Foresti, Fausto

2017-01-01

Satellite DNA (satDNA) is an abundant fraction of repetitive DNA in eukaryotic genomes and plays an important role in genome organization and evolution. In general, satDNA sequences follow a concerted evolutionary pattern through the intragenomic homogenization of different repeat units. In addition, the satDNA library hypothesis predicts that related species share a series of satDNA variants descended from a common ancestor species, with differential amplification of different satDNA variants. The finding of a same satDNA family in species belonging to different genera within Characidae fish provided the opportunity to test both concerted evolution and library hypotheses. For this purpose, we analyzed here sequence variation and abundance of this satDNA family in ten species, by a combination of next generation sequencing (NGS), PCR and Sanger sequencing, and fluorescence in situ hybridization (FISH). We found extensive between-species variation for the number and size of pericentromeric FISH signals. At genomic level, the analysis of 1000s of DNA sequences obtained by Illumina sequencing and PCR amplification allowed defining 150 haplotypes which were linked in a common minimum spanning tree, where different patterns of concerted evolution were apparent. This also provided a glimpse into the satDNA library of this group of species. In consistency with the library hypothesis, different variants for this satDNA showed high differences in abundance between species, from highly abundant to simply relictual variants. PMID:28855916

Conquering the SAT: How Parents Can Help Teens Overcome the Pressure and Succeed

ERIC Educational Resources Information Center

Johnson, Ned; Eskelsen, Emily Warner

2006-01-01

This insightful and practical guide for parents shows how they often undermine rather than encourage their teens' success on one of the most stressful standardized tests--the SAT--and what strategies will remedy the problem. In recent years this test has taken on fearsome proportions, matched only by the growing competition for slots at major…

Validating Standardized Testing: The Role of the SAT and ACT in Undergraduate Admissions. [Hearing before the California Legislature, Senate Select Committee on Higher Education Admissions and Outreach, Sacramento, California, February 5, 1998].

ERIC Educational Resources Information Center

California State Legislature, Sacramento. Senate Select Committee on Higher Education Admissions and Outreach.

This report contains testimony and materials presented at the California Senate Select Committee on Higher Education Admissions and Outreach hearing, February 1998, held to examine the role of the Scholastic Assessment Test (SAT) and the American College Test (ACT) in undergraduate admissions to the public universities of California. In her…

Application of the CloudSat and NEXRAD Radars Toward Improvements in High Resolution Operational Forecasts

NASA Technical Reports Server (NTRS)

Molthan, A. L.; Haynes, J. A.; Case, J. L.; Jedlovec, G. L.; Lapenta, W. M.

2008-01-01

As computational power increases, operational forecast models are performing simulations with higher spatial resolution allowing for the transition from sub-grid scale cloud parameterizations to an explicit forecast of cloud characteristics and precipitation through the use of single- or multi-moment bulk water microphysics schemes. investments in space-borne and terrestrial remote sensing have developed the NASA CloudSat Cloud Profiling Radar and the NOAA National Weather Service NEXRAD system, each providing observations related to the bulk properties of clouds and precipitation through measurements of reflectivity. CloudSat and NEXRAD system radars observed light to moderate snowfall in association with a cold-season, midlatitude cyclone traversing the Central United States in February 2007. These systems are responsible for widespread cloud cover and various types of precipitation, are of economic consequence, and pose a challenge to operational forecasters. This event is simulated with the Weather Research and Forecast (WRF) Model, utilizing the NASA Goddard Cumulus Ensemble microphysics scheme. Comparisons are made between WRF-simulated and observed reflectivity available from the CloudSat and NEXRAD systems. The application of CloudSat reflectivity is made possible through the QuickBeam radiative transfer model, with cautious application applied in light of single scattering characteristics and spherical target assumptions. Significant differences are noted within modeled and observed cloud profiles, based upon simulated reflectivity, and modifications to the single-moment scheme are tested through a supplemental WRF forecast that incorporates a temperature dependent snow crystal size distribution.

Evaluation of the solid phase competition ELISA for detecting antibodies against the six foot-and-mouth disease virus non-O serotypes.

PubMed

Li, Yanmin; Swabey, Kate G; Gibson, Debi; Keel, Phil J; Hamblin, Pip; Wilsden, Ginette; Corteyn, Mandy; Ferris, Nigel P

2012-08-01

The solid-phase competition ELISA (SPCE) has been evaluated in both screening and titration assay formats for detecting antibodies against foot-and-mouth disease virus (FMDV) for the six non-O serotypes A, C, SAT 1, SAT 2, SAT 3 and Asia 1. Cut-off values were determined as a percentage inhibition of 40 for the SAT serotypes and 50 for serotypes A, C and Asia 1, which gave rise to specificity values ranging from 99.41% to 99.9% for the different serotypes. The relative sensitivity between the SPCE and LPBE/virus neutralisation test was 100%/109%. Antiserum titres derived by the SPCE for samples of serotypes O, A(22) and Asia 1 were more than 11, 1 and 5 times of those determined by virus neutralisation test, respectively. This study indicated that the non-type O SPCEs have sufficient sensitivities and specificities for use as serological diagnostic tests for the qualitative and quantitative detection of antibodies against FMDV. Copyright © 2012 Elsevier B.V. All rights reserved.

LighSail Students Testing - ELaNa XI

NASA Image and Video Library

2014-09-23

Students Alex Diaz and Riki Munakata of California Polytechnic State University testing the LightSail CubeSat. LightSail is a citizen-funded technology demonstration mission sponsored by the Planetary Society using solar propulsion for CubeSats. The spacecraft is designed to “sail” on the energy of solar photons striking the thin, reflective sail material. The first LightSail mission is designed to test the spacecraft’s critical systems, including the sequence to autonomously deploy a Mylar solar sail with an area of 32 square meters (344 square feet). The Planetary Society is planning a second, full solar sailing demonstration flight for 2016. Light is made of packets of energy called photons. While photons have no mass, they have energy and momentum. Solar sails use this momentum as a method of propulsion, creating flight by light. LightSail’s solar sail is packaged into a three-unit CubeSat about the size of a loaf of bread. Launched by NASA’s CubeSat Launch Initiative on the ELaNa XI mission as an auxiliary payload aboard the U.S. Air Force X-37B space plane mission on May 20, 2015.

An efficient algorithm for computing fixed length attractors based on bounded model checking in synchronous Boolean networks with biochemical applications.

PubMed

Li, X Y; Yang, G W; Zheng, D S; Guo, W S; Hung, W N N

2015-04-28

Genetic regulatory networks are the key to understanding biochemical systems. One condition of the genetic regulatory network under different living environments can be modeled as a synchronous Boolean network. The attractors of these Boolean networks will help biologists to identify determinant and stable factors. Existing methods identify attractors based on a random initial state or the entire state simultaneously. They cannot identify the fixed length attractors directly. The complexity of including time increases exponentially with respect to the attractor number and length of attractors. This study used the bounded model checking to quickly locate fixed length attractors. Based on the SAT solver, we propose a new algorithm for efficiently computing the fixed length attractors, which is more suitable for large Boolean networks and numerous attractors' networks. After comparison using the tool BooleNet, empirical experiments involving biochemical systems demonstrated the feasibility and efficiency of our approach.

NASA's CubeQuest Challenge - From Ground Tournaments to Lunar and Deep Space Derby

NASA Technical Reports Server (NTRS)

Hyde, Elizabeth Lee; Cockrell, James J.

2017-01-01

The First Flight of NASA's Space Launch System will feature 13 CubeSats that will launch into cis-lunar space. Three of these CubeSats are winners of the CubeQuest Challenge, part of NASA's Space Technology Mission Directorate (STMD) Centennial Challenge Program. In order to qualify for launch on EM-1, the winning teams needed to win a series of Ground Tournaments, periodically held since 2015. The final Ground Tournament, GT-4, was held in May 2017, and resulted in the Top 3 selection for the EM-1 launch opportunity. The Challenge now proceeds to the in-space Derbies, where teams must build and test their spacecraft before launch on EM-1. Once in space, they will compete for a variety of Communications and Propulsion-based challenges. This is the first Centennial Challenge to compete in space and is a springboard for future in-space Challenges. In addition, the technologies gained from this challenge will also propel development of deep space CubeSats.

MethaneSat: Detecting Methane Emissions in the Barnett Shale Region

NASA Astrophysics Data System (ADS)

Propp, A. M.; Benmergui, J. S.; Turner, A. J.; Wofsy, S. C.

2017-12-01

In this study, we investigate the new information that will be provided by MethaneSat, a proposed satellite that will measure the total column dry-air mole fraction of methane at 1x1 km or 2x2 km spatial resolution with 0.1-0.2% random error. We run an atmospheric model to simulate MethaneSat's ability to characterize methane emissions from the Barnett Shale, a natural gas province in Texas. For comparison, we perform observation system simulation experiments (OSSEs) for MethaneSat, the National Oceanic and Atmospheric administration (NOAA) surface and aircraft network, and Greenhouse Gases Observing Satellite (GOSAT). The results demonstrate the added benefit that MethaneSat would provide in our efforts to monitor and report methane emissions. We find that MethaneSat successfully quantifies total methane emissions in the region, as well as their spatial distribution and steep gradients. Under the same test conditions, both the NOAA network and GOSAT fail to capture this information. Furthermore, we find that the results for MethaneSat depend far less on the prior emission estimate than do those for the other observing systems, demonstrating the benefit of high sampling density. The results suggest that MethaneSat would be an incredibly useful tool for obtaining detailed methane emission information from oil and gas provinces around the world.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-045009 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it deploys a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing. Station solar array panels, Earth's horizon and the blackness of space provide the backdrop for the scene.

Near Earth Network (NEN) CubeSat Communications

NASA Technical Reports Server (NTRS)

Schaire, Scott

2017-01-01

The NASA Near Earth Network (NEN) consists of globally distributed tracking stations, including NASA, commercial, and partner ground stations, that are strategically located to maximize the coverage provided to a variety of orbital and suborbital missions, including those in LEO (Low Earth Orbit), GEO (Geosynchronous Earth Orbit), HEO (Highly Elliptical Orbit), lunar and L1-L2 orbits. The NEN's future mission set includes and will continue to include CubeSat missions. The first NEN-supported CubeSat mission will be the Cubesat Proximity Operations Demonstration (CPOD) launching into LEO in 2017. The majority of the CubeSat missions destined to fly on EM-1, launching in late 2018, many in a lunar orbit, will communicate with ground-based stations via X-band and will utilize the NASA Jet Propulsion Laboratory (JPL)-developed IRIS (Satellite Communication for Air Traffic Management) radio. The NEN recognizes the important role CubeSats are beginning to play in carrying out NASAs mission and is therefore investigating the modifications needed to provide IRIS radio compatibility. With modification, the NEN could potentially expand support to the EM-1 (Exploration Mission-1) lunar CubeSats. The NEN could begin providing significant coverage to lunar CubeSat missions utilizing three to four of the NEN's mid-latitude sites. This coverage would supplement coverage provided by the JPL Deep Space Network (DSN). The NEN, with smaller apertures than DSN, provides the benefit of a larger beamwidth that could be beneficial in the event of uncertain ephemeris data. In order to realize these benefits the NEN would need to upgrade stations targeted based on coverage ability and current configuration ease of upgrade, to ensure compatibility with the IRIS radio. In addition, the NEN is working with CubeSat radio developers to ensure NEN compatibility with alternative CubeSat radios for Lunar and L1-L2 CubeSats. The NEN has provided NEN compatibility requirements to several radio developers who are developing radios that offer lower cost and, in some cases, more capabilities with fewer constraints. The NEN is ready to begin supporting CubeSat missions. The NEN is considering network upgrades to broaden the types of CubeSat missions that can be supported and is supporting both the CubeSat community and radio developers to ensure future CubeSat missions have multiple options when choosing a network for their communications support.

NASA Near Earth Network (NEN) Support for Lunar and L1/L2 CubeSats

NASA Technical Reports Server (NTRS)

Schaire, Scott H.

2017-01-01

The NASA Near Earth Network (NEN) consists of globally distributed tracking stations, including NASA, commercial, and partner ground stations, that are strategically located to maximize the coverage provided to a variety of orbital and suborbital missions, including those in LEO, GEO, HEO, lunar and L1/L2 orbits. The NENs future mission set includes and will continue to include CubeSat missions. The first NEN supported CubeSat mission will be the Cubesat Proximity Operations Demonstration (CPOD) launching into low earth orbit (LEO) in early 2017. The majority of the CubeSat missions destined to fly on EM-1, launching in late 2018, many in a lunar orbit, will communicate with ground based stations via X-band and will utilize the NASA Jet Propulsion Laboratory (JPL) developed IRIS radio. The NEN recognizes the important role CubeSats are beginning to play in carrying out NASAs mission and is therefore investigating the modifications needed to provide IRIS radio compatibility. With modification, the NEN could potentially expand support to the EM-1 lunar CubeSats. The NEN could begin providing significant coverage to lunar CubeSat missions utilizing three to four of the NENs mid-latitude sites. This coverage would supplement coverage provided by the JPL Deep Space Network (DSN). The NEN, with smaller apertures than DSN, provides the benefit of a larger beamwidth that could be beneficial in the event of uncertain ephemeris data. In order to realize these benefits the NEN would need to upgrade stations targeted based on coverage ability and current configurationease of upgrade, to ensure compatibility with the IRIS radio.In addition, the NEN is working with CubeSat radio developers to ensure NEN compatibility with alternative CubeSat radios for Lunar and L1/L2 CubeSats. The NEN has provided NEN compatibility requirements to several radio developers who are developing radios that offer lower cost and, in some cases, more capabilities with fewer constraints. The NEN is ready to begin supporting CubeSat missions. The NEN is considering network upgrades to broaden the types of CubeSat missions that can be supported and is supporting both the CubeSat community and radio developers to ensure future CubeSat missions have multiple options when choosing a network for their communications support.

CubeSat Attitude Determination and Helmholtz Cage Design

DTIC Science & Technology

2012-03-01

4.2.2. 3.6 CubeSat Components The CubeSat used in this experiment is commanded and controlled via the Arduino Mega board that is based on the ATmel...UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base , Ohio APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED The views...ENY/12-M03 Abstract A method of 3-axis satellite attitude determination utilizing six body-fixed light sensors and a 3-axis magnetometer is analyzed. A

On the verge of an astronomy CubeSat revolution

NASA Astrophysics Data System (ADS)

Shkolnik, Evgenya L.

2018-05-01

CubeSats are small satellites built in standard sizes and form factors, which have been growing in popularity but have thus far been largely ignored within the field of astronomy. When deployed as space-based telescopes, they enable science experiments not possible with existing or planned large space missions, filling several key gaps in astronomical research. Unlike expensive and highly sought after space telescopes such as the Hubble Space Telescope, whose time must be shared among many instruments and science programs, CubeSats can monitor sources for weeks or months at time, and at wavelengths not accessible from the ground such as the ultraviolet, far-infrared and low-frequency radio. Science cases for CubeSats being developed now include a wide variety of astrophysical experiments, including exoplanets, stars, black holes and radio transients. Achieving high-impact astronomical research with CubeSats is becoming increasingly feasible with advances in technologies such as precision pointing, compact sensitive detectors and the miniaturization of propulsion systems. CubeSats may also pair with the large space- and ground-based telescopes to provide complementary data to better explain the physical processes observed.

Test and On-Orbit Experiences of FalconSAT-3

NASA Astrophysics Data System (ADS)

Saylor, W. W.; France, M. E. B.

2008-08-01

The fundamental objectives of the capstone design project in the Department of Astronautics at the United States Air Force Academy (USAFA) are for cadets to learn important engineering lessons by executing a real space mission on a Department of Defense-funded satellite project. FalconSAT-3 is a 50 kg, gravity gradient-stabilized designed and built by cadets and launched March 2007 on the first ESPA (Enhanced extended launch vehicle Satellite Payload Adapter) mission. FalconSAT-3 was one of six satellites integrated onto the launch vehicle and the nature of the mission made it that the satellite was subject to the full formality of testing requirements. Two successive gravity gradient booms failed either design requirements or environmental testing; design requirements grew dramatically during the design phase; ambiguous thermal vacuum test results led to uncertainty at launch; and after launch it was not possible to contact the satellite for several weeks.

Research, Development and Testing of a Fault-Tolerant FPGA-Based Sequencer for CubeSat Launching Applications

DTIC Science & Technology

2013-03-01

amounts of time and effort to implement. Future testing with commercial, fault-tolerant synthesis software, under a radiation environment, will yield ...initial viewpoint of the author is to take the flash-based FPGA route. This will yield a simple, reconfigurable circuit while providing the added...structure seen in Figure 30. Each of these full adder blocks were replaced in subsequent iterations to yield proper comparison with this baseline

Independent associations of insulin resistance with high whole-body intermuscular and low leg subcutaneous adipose tissue distribution in obese HIV-infected women123

PubMed Central

Albu, Jeanine B; Kenya, Sonjia; He, Qing; Wainwright, Marsha; Berk, Evan S; Heshka, Stanley; Kotler, Donald P; Engelson, Ellen S

2009-01-01

Background Obesity and insulin resistance are growing problems in HIV-positive (HIV+) women receiving highly active antiretroviral therapy (HAART). Objective The objective was to determine the contribution of adipose tissue (AT) enlargement and distribution to the presence of insulin resistance in obese HIV+ women. Design Whole-body intermuscular AT (IMAT), visceral AT (VAT), subcutaneous AT (SAT), and SAT distribution (leg versus upper body) were measured by whole-body magnetic resonance imaging. Insulin sensitivity (SI) was measured with an intravenous glucose tolerance test in obese HIV+ women recruited because of their desire to lose weight (n = 17) and in obese healthy controls (n = 32). Results The HIV+ women had relatively less whole-body SAT and more VAT and IMAT than did the controls (P < 0.05 for all). A significant interaction by HIV status was observed for the relation of total SAT with SI (P < 0.001 for the regression’s slope interactions after adjustment for age, height, and weight). However, relations of IMAT, VAT, and SAT distribution (leg SAT as a percentage of total SAT; leg SAT%) with SI did not differ significantly between groups. For both groups combined, the best model predicting a low SI included significant contributions by both high IMAT and low leg SAT%, independent of age, height, and weight, and no interaction between groups was observed (overall r2 = 0.44, P = 0.0003). Conclusion In obese HIV+ women, high whole-body IMAT and low leg SAT% distribution are independently associated with insulin resistance. PMID:17616768

The Effects of Coaching on Standardized Admission Examinations. Staff Memorandum of the Boston Regional Office of the Federal Trade Commission.

ERIC Educational Resources Information Center

Federal Trade Commission, Washington, DC. Bureau of Consumer Protection.

A non-experimental design was used to determine if scores of students enrolled in specified major coaching schools were significantly higher than scores of comparable uncoached groups. Score increases at two Scholastic Aptitude Test (SAT) coaching schools and Law School Admission Test (LSAT) schools were compared. Over 1,400 SAT examinees and…

Learning in the Shadows and in the Light of Day: A Commentary on "Shadow Education, American Style: Test Preparation, the SAT and College Enrollment"

ERIC Educational Resources Information Center

Grodsky, Eric

2010-01-01

Buchmann, Condron and Roscigno argue in their article, "Shadow Education, American Style: Test Preparation, the SAT and College Enrollment," that the activities in which students engage to prepare for college entrance exams are forms of shadow education, a means by which more advantaged parents seek to pass their privileged status along…

Technology transfer program of Microlabsat

NASA Astrophysics Data System (ADS)

Nakamura, Y.; Hashimoto, H.

2004-11-01

A 50kg-class small satellite developed by JAXA called "MicroLabSat" was launched piggyback by H-IIA rocket No. 4 on 14 December 2002. This satellite will demonstrate small satellite bus technology and conduct experiments on a new separator feasibility and remote inspection technology. All missions were completed successfully on 25 May 2003. Furthermore, the hand-construction by young JAXA engineers motivated these engineers to higher performance in learning design, assembly and testing technology. Small and medium-sized Japanese companies have recently joined together and initiated a project to develop a small satellite. The goal of the project is to commercialise small satellites, which will require low- cost development. Therefore, they have started with a satellite incorporating the components and bus technologies of MicroLabSat and have been technically supported by universities and JAXA since 2004. This satellite project, in which industry, universities and a space agency are collaborating, seeks to meet the technical challenge of launching a low-cost satellite. This paper reports JAX's strategies for developing a small satellite for demonstrating space technology as well as the development and operation results of MicroLabSat. It also describes the project status of an industry-based satellite, developed through collaboration among industries, universities and the space agency, and how the technologies of MicroLabSat are applied.

RainCube 6U CubeSat

NASA Image and Video Library

2018-05-17

The RainCube 6U CubeSat with fully-deployed antenna. RainCube, CubeRRT and TEMPEST-D are currently integrated aboard Orbital ATKs Cygnus spacecraft and are awaiting launch on an Antares rocket. After the CubeSats have arrived at the station, they will be deployed into low-Earth orbit and will begin their missions to test these new technologies useful for predicting weather, ensuring data quality, and helping researchers better understand storms. https://photojournal.jpl.nasa.gov/catalog/PIA22457

Systematic review: Comparison of Xpert MTB/RIF, LAMP and SAT methods for the diagnosis of pulmonary tuberculosis.

PubMed

Yan, Liping; Xiao, Heping; Zhang, Qing

2016-01-01

Technological advances in nucleic acid amplification have led to breakthroughs in the early detection of PTB compared to traditional sputum smear tests. The sensitivity and specificity of loop-mediated isothermal amplification (LAMP), simultaneous amplification testing (SAT), and Xpert MTB/RIF for the diagnosis of pulmonary tuberculosis were evaluated. A critical review of previous studies of LAMP, SAT, and Xpert MTB/RIF for the diagnosis of pulmonary tuberculosis that used laboratory culturing as the reference method was carried out together with a meta-analysis. In 25 previous studies, the pooled sensitivity and specificity of the diagnosis of tuberculosis were 93% and 94% for LAMP, 96% and 88% for SAT, and 89% and 98% for Xpert MTB/RIF. The I(2) values for the pooled data were >80%, indicating significant heterogeneity. In the smear-positive subgroup analysis of LAMP, the sensitivity increased from 93% to 98% (I(2) = 2.6%), and specificity was 68% (I(2) = 38.4%). In the HIV-infected subgroup analysis of Xpert MTB/RIF, the pooled sensitivity and specificity were 79% (I(2) = 72.9%) and 99% (I(2) = 64.4%). In the HIV-negative subgroup analysis for Xpert MTB/RIF, the pooled sensitivity and specificity were 72% (I(2) = 49.6%) and 99% (I(2) = 64.5%). LAMP, SAT and Xpert MTB/RIF had comparably high levels of sensitivity and specificity for the diagnosis of tuberculosis. The diagnostic sensitivity and specificity of three methods were similar, with LAMP being highly sensitive for the diagnosis of smear-positive PTB. The cost effectiveness of LAMP and SAT make them particularly suitable tests for diagnosing PTB in developing countries. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Biomechanical Assessment of Hand/Arm Force with Pneumatic Nail Gun Actuation Systems.

PubMed

Lowe, Brian D; Albers, James; Hudock, Stephen D

2014-09-01

A biomechanical model is presented, and combined with measurements of tip press force, to estimate total user hand force associated with two pneumatic nail gun trigger systems. The contact actuation trigger (CAT) can fire a nail when the user holds the trigger depressed first and then "bumps" the nail gun tip against the workpiece. With a full sequential actuation trigger (SAT) the user must press the tip against the workpiece prior to activating the trigger. The SAT is demonstrably safer in reducing traumatic injury risk, but increases the duration (and magnitude) of tip force exertion. Time integrated (cumulative) hand force was calculated for a single user from measurements of the tip contact force with the workpiece and transfer time between nails as inputs to a static model of the nail gun and workpiece in two nailing task orientations. The model shows the hand force dependence upon the orientation of the workpiece in addition to the trigger system. Based on standard time allowances from work measurement systems (i.e. Methods-Time Measurement - 1) it is proposed that efficient application of hand force with the SAT in maintaining tip contact can reduce force exertion attributable to the sequential actuation trigger to 2-8% (horizontal nailing) and 9-20% (vertical nailing) of the total hand/arm force. The present model is useful for considering differences in cumulative hand/arm force exposure between the SAT and CAT systems and may explain the appeal of the CAT trigger in reducing the user's perception of muscular effort.

A Biomechanical Assessment of Hand/Arm Force with Pneumatic Nail Gun Actuation Systems

PubMed Central

Lowe, Brian D.; Albers, James; Hudock, Stephen D.

2015-01-01

A biomechanical model is presented, and combined with measurements of tip press force, to estimate total user hand force associated with two pneumatic nail gun trigger systems. The contact actuation trigger (CAT) can fire a nail when the user holds the trigger depressed first and then “bumps” the nail gun tip against the workpiece. With a full sequential actuation trigger (SAT) the user must press the tip against the workpiece prior to activating the trigger. The SAT is demonstrably safer in reducing traumatic injury risk, but increases the duration (and magnitude) of tip force exertion. Time integrated (cumulative) hand force was calculated for a single user from measurements of the tip contact force with the workpiece and transfer time between nails as inputs to a static model of the nail gun and workpiece in two nailing task orientations. The model shows the hand force dependence upon the orientation of the workpiece in addition to the trigger system. Based on standard time allowances from work measurement systems (i.e. Methods-Time Measurement - 1) it is proposed that efficient application of hand force with the SAT in maintaining tip contact can reduce force exertion attributable to the sequential actuation trigger to 2–8% (horizontal nailing) and 9–20% (vertical nailing) of the total hand/arm force. The present model is useful for considering differences in cumulative hand/arm force exposure between the SAT and CAT systems and may explain the appeal of the CAT trigger in reducing the user’s perception of muscular effort. PMID:26321780

Making every gram count - Big measurements from tiny platforms (Invited)

NASA Astrophysics Data System (ADS)

Fish, C. S.; Neilsen, T. L.; Stromberg, E. M.

2013-12-01

The most significant advances in Earth, solar, and space physics over the next decades will originate from new, system-level observational techniques. The most promising technique to still be fully developed and exploited requires conducting multi-point or distributed constellation-based observations. This system-level observational approach is required to understand the 'big picture' coupling between disparate regions such as the solar-wind, magnetosphere, ionosphere, upper atmosphere, land, and ocean. The national research council, NASA science mission directorate, and the larger heliophysics community have repeatedly identified the pressing need for multipoint scientific investigations to be implemented via satellite constellations. The NASA Solar Terrestrial Probes Magnetospheric Multiscale (MMS) mission and NASA Earth Science Division's 'A-train', consisting of the AQUA, CloudSat, CALIPSO and AURA satellites, are examples of such constellations. However, the costs to date of these and other similar proposed constellations have been prohibitive given the 'large satellite' architectures and the multiple launch vehicles required for implementing the constellations. Financially sustainable development and deployment of multi-spacecraft constellations can only be achieved through the use of small spacecraft that allow for multiple hostings per launch vehicle. The revolution in commercial mobile and other battery powered consumer technology has helped enable researchers in recent years to build and fly very small yet capable satellites, principally CubeSats. A majority of the CubeSat activity and development to date has come from international academia and the amateur radio satellite community, but several of the typical large-satellite vendors have developed CubeSats as well. Recent government-sponsored CubeSat initiatives, such as the NRO Colony, NSF CubeSat Space Weather, NASA Office of Chief Technologist Edison and CubeSat Launch Initiative (CSLI) Educational Launch of Nanosatellites Educational Launch of Nano-satellites (ELaNa), the Air Force Space Environmental NanoSat Experiment (SENSE), and the ESA QB50 programs have spurred the development of very proficient miniature space sensors and technologies that enable technology demonstration, space and earth science research, and operational CubeSat based missions. In this paper we will review many of the small, low cost sensor and instrumentation technologies that have been developed to date as part of the CubeSat movement and examine how these new CubeSat based technologies are helping us do more with less.

International Study to Evaluate PCR Methods for Detection of Trypanosoma cruzi DNA in Blood Samples from Chagas Disease Patients

PubMed Central

Schijman, Alejandro G.; Bisio, Margarita; Orellana, Liliana; Sued, Mariela; Duffy, Tomás; Mejia Jaramillo, Ana M.; Cura, Carolina; Auter, Frederic; Veron, Vincent; Qvarnstrom, Yvonne; Deborggraeve, Stijn; Hijar, Gisely; Zulantay, Inés; Lucero, Raúl Horacio; Velazquez, Elsa; Tellez, Tatiana; Sanchez Leon, Zunilda; Galvão, Lucia; Nolder, Debbie; Monje Rumi, María; Levi, José E.; Ramirez, Juan D.; Zorrilla, Pilar; Flores, María; Jercic, Maria I.; Crisante, Gladys; Añez, Néstor; De Castro, Ana M.; Gonzalez, Clara I.; Acosta Viana, Karla; Yachelini, Pedro; Torrico, Faustino; Robello, Carlos; Diosque, Patricio; Triana Chavez, Omar; Aznar, Christine; Russomando, Graciela; Büscher, Philippe; Assal, Azzedine; Guhl, Felipe; Sosa Estani, Sergio; DaSilva, Alexandre; Britto, Constança; Luquetti, Alejandro; Ladzins, Janis

2011-01-01

Background A century after its discovery, Chagas disease still represents a major neglected tropical threat. Accurate diagnostics tools as well as surrogate markers of parasitological response to treatment are research priorities in the field. The purpose of this study was to evaluate the performance of PCR methods in detection of Trypanosoma cruzi DNA by an external quality evaluation. Methodology/Findings An international collaborative study was launched by expert PCR laboratories from 16 countries. Currently used strategies were challenged against serial dilutions of purified DNA from stocks representing T. cruzi discrete typing units (DTU) I, IV and VI (set A), human blood spiked with parasite cells (set B) and Guanidine Hidrochloride-EDTA blood samples from 32 seropositive and 10 seronegative patients from Southern Cone countries (set C). Forty eight PCR tests were reported for set A and 44 for sets B and C; 28 targeted minicircle DNA (kDNA), 13 satellite DNA (Sat-DNA) and the remainder low copy number sequences. In set A, commercial master mixes and Sat-DNA Real Time PCR showed better specificity, but kDNA-PCR was more sensitive to detect DTU I DNA. In set B, commercial DNA extraction kits presented better specificity than solvent extraction protocols. Sat-DNA PCR tests had higher specificity, with sensitivities of 0.05–0.5 parasites/mL whereas specific kDNA tests detected 5.10−3 par/mL. Sixteen specific and coherent methods had a Good Performance in both sets A and B (10 fg/µl of DNA from all stocks, 5 par/mL spiked blood). The median values of sensitivities, specificities and accuracies obtained in testing the Set C samples with the 16 tests determined to be good performing by analyzing Sets A and B samples varied considerably. Out of them, four methods depicted the best performing parameters in all three sets of samples, detecting at least 10 fg/µl for each DNA stock, 0.5 par/mL and a sensitivity between 83.3–94.4%, specificity of 85–95%, accuracy of 86.8–89.5% and kappa index of 0.7–0.8 compared to consensus PCR reports of the 16 good performing tests and 63–69%, 100%, 71.4–76.2% and 0.4–0.5, respectively compared to serodiagnosis. Method LbD2 used solvent extraction followed by Sybr-Green based Real time PCR targeted to Sat-DNA; method LbD3 used solvent DNA extraction followed by conventional PCR targeted to Sat-DNA. The third method (LbF1) used glass fiber column based DNA extraction followed by TaqMan Real Time PCR targeted to Sat-DNA (cruzi 1/cruzi 2 and cruzi 3 TaqMan probe) and the fourth method (LbQ) used solvent DNA extraction followed by conventional hot-start PCR targeted to kDNA (primer pairs 121/122). These four methods were further evaluated at the coordinating laboratory in a subset of human blood samples, confirming the performance obtained by the participating laboratories. Conclusion/Significance This study represents a first crucial step towards international validation of PCR procedures for detection of T. cruzi in human blood samples. PMID:21264349

Exploiting artificial intelligence for in-situ analysis of high-resolution radio emission measurements on a CubeSat

NASA Astrophysics Data System (ADS)

Isham, Brett; Bergman, Jan; Krause, Linda; Rincon-Charris, Amilcar; Bruhn, Fredrik; Funk, Peter; Stramkals, Arturs

2016-07-01

CubeSat missions are intentionally constrained by the limitations of their small platform. Mission payloads designed for low volume, mass, and power, may however be disproportionally limited by available telemetry allocations. In many cases, it is the data delivered to the ground which determines the value of the mission. However, transmitting more data does not necessarily guarantee high value, since the value also depends on data quality. By exploiting fast on-board computing and efficient artificial intelligence (AI) algorithms for analysis and data selection, the usage of the telemetry link can be optimized and value added to the mission. This concept is being implemented on the Puerto Rico CubeSat, which will make measurements of ambient ionospheric radio waves and ion irregularities and turbulence. Principle project goals include providing aerospace and systems engineering experiences to students. Science objectives include the study of natural space plasma processes to aid in better understanding of space weather and the Sun to Earth connection, and in-situ diagnostics of ionospheric modification experiments using high-power ground-based radio transmitters. We hope that this project might point the way to the productive use of AI in space and other remote, low-data-bandwidth environments.

Non-"g" Residuals of the SAT and ACT Predict Specific Abilities

ERIC Educational Resources Information Center

Coyle, Thomas R.; Purcell, Jason M.; Snyder, Anissa C.; Kochunov, Peter

2013-01-01

This research examined whether non-"g" residuals of the SAT and ACT subtests, obtained after removing g, predicted specific abilities. Non-"g" residuals of the verbal and math subtests of the SAT and ACT were correlated with academic (verbal and math) and non-academic abilities (speed and shop), both based on the Armed Services…

Post optimization paradigm in maximum 3-satisfiability logic programming

NASA Astrophysics Data System (ADS)

Mansor, Mohd. Asyraf; Sathasivam, Saratha; Kasihmuddin, Mohd Shareduwan Mohd

2017-08-01

Maximum 3-Satisfiability (MAX-3SAT) is a counterpart of the Boolean satisfiability problem that can be treated as a constraint optimization problem. It deals with a conundrum of searching the maximum number of satisfied clauses in a particular 3-SAT formula. This paper presents the implementation of enhanced Hopfield network in hastening the Maximum 3-Satisfiability (MAX-3SAT) logic programming. Four post optimization techniques are investigated, including the Elliot symmetric activation function, Gaussian activation function, Wavelet activation function and Hyperbolic tangent activation function. The performances of these post optimization techniques in accelerating MAX-3SAT logic programming will be discussed in terms of the ratio of maximum satisfied clauses, Hamming distance and the computation time. Dev-C++ was used as the platform for training, testing and validating our proposed techniques. The results depict the Hyperbolic tangent activation function and Elliot symmetric activation function can be used in doing MAX-3SAT logic programming.

CSUNSat-1 Team working on their CubeSat at California State University Northridge

NASA Image and Video Library

2015-03-02

CSUNSat-1 Team (Adam Kaplan, James Flynn, Donald Eckels) working on their CubeSat at California State University Northridge. The primary mission of CSUNSat1 is to space test an innovative low temperature capable energy storage system developed by the Jet Propulsion Laboratory, raising its TRL level to 7 from 4 to 5. The success of this energy storage system will enable future missions, especially those in deep space to do more science while requiring less energy, mass and volume. This CubeSat was designed, built, programmed, and tested by a team of over 70 engineering and computer science students at CSUN.  The primary source of funding for CSUNSat1 comes from NASA’s Smallest Technology Partnership program. Launched by NASA’s CubeSat Launch Initiative NET April 18, 2017 ELaNa XVII mission on the seventh Orbital-ATK Cygnus Commercial Resupply Services (OA-7) to the International Space Station and deployed on tbd.

The Step approach to Message Design and Testing (SatMDT): A conceptual framework to guide the development and evaluation of persuasive health messages.

PubMed

Lewis, Ioni; Watson, Barry; White, Katherine M

2016-12-01

This paper provides an important and timely overview of a conceptual framework designed to assist with the development of message content, as well as the evaluation, of persuasive health messages. While an earlier version of this framework was presented in a prior publication by the authors in 2009, important refinements to the framework have seen it evolve in recent years, warranting the need for an updated review. This paper outlines the Step approach to Message Design and Testing (or SatMDT) in accordance with the theoretical evidence which underpins, as well as empirical evidence which demonstrates the relevance and feasibility of, each of the framework's steps. The development and testing of the framework have thus far been based exclusively within the road safety advertising context; however, the view expressed herein is that the framework may have broader appeal and application to the health persuasion context. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sat1 is dispensable for active oxalate secretion in mouse duodenum

PubMed Central

Ko, Narae; Knauf, Felix; Jiang, Zhirong; Markovich, Daniel

2012-01-01

Mice deficient for the apical membrane oxalate transporter SLC26A6 develop hyperoxalemia, hyperoxaluria, and calcium oxalate stones due to a defect in intestinal oxalate secretion. However, the nature of the basolateral membrane oxalate transport process that operates in series with SLC26A6 to mediate active oxalate secretion in the intestine remains unknown. Sulfate anion transporter-1 (Sat1 or SLC26A1) is a basolateral membrane anion exchanger that mediates intestinal oxalate transport. Moreover, Sat1-deficient mice also have a phenotype of hyperoxalemia, hyperoxaluria, and calcium oxalate stones. We, therefore, tested the role of Sat1 in mouse duodenum, a tissue with Sat1 expression and SLC26A6-dependent oxalate secretion. Although the active secretory flux of oxalate across mouse duodenum was strongly inhibited (>90%) by addition of the disulfonic stilbene DIDS to the basolateral solution, secretion was unaffected by changes in medium concentrations of sulfate and bicarbonate, key substrates for Sat1-mediated anion exchange. Inhibition of intracellular bicarbonate production by acetazolamide and complete removal of bicarbonate from the buffer also produced no change in oxalate secretion. Finally, active oxalate secretion was not reduced in Sat1-null mice. We conclude that a DIDS-sensitive basolateral transporter is involved in mediating oxalate secretion across mouse duodenum, but Sat1 itself is dispensable for this process. PMID:22517357

Centromeric and non-centromeric satellite DNA organisation differs in holocentric Rhynchospora species.

PubMed

Ribeiro, Tiago; Marques, André; Novák, Petr; Schubert, Veit; Vanzela, André L L; Macas, Jiri; Houben, Andreas; Pedrosa-Harand, Andrea

2017-03-01

Satellite DNA repeats (or satDNA) are fast-evolving sequences usually associated with condensed heterochromatin. To test whether the chromosomal organisation of centromeric and non-centromeric satDNA differs in species with holocentric chromosomes, we identified and characterised the major satDNA families in the holocentric Cyperaceae species Rhynchospora ciliata (2n = 10), R. globosa (2n = 50) and R. tenuis (2n = 2x = 4 and 2n = 4x = 8). While conserved centromeric repeats (present in R. ciliata and R. tenuis) revealed linear signals at both chromatids, non-centromeric, species-specific satDNAs formed distinct clusters along the chromosomes. Colocalisation of both repeat types resulted in a ladder-like hybridisation pattern at mitotic chromosomes. In interphase, the centromeric satDNA was dispersed while non-centromeric satDNA clustered and partly colocalised to chromocentres. Despite the banding-like hybridisation patterns of the clustered satDNA, the identification of chromosome pairs was impaired due to the irregular hybridisation patterns of the homologues in R. tenuis and R. ciliata. These differences are probably caused by restricted or impaired meiotic recombination as reported for R. tenuis, or alternatively by complex chromosome rearrangements or unequal condensation of homologous metaphase chromosomes. Thus, holocentricity influences the chromosomal organisation leading to differences in the distribution patterns and condensation dynamics of centromeric and non-centromeric satDNA.

The Stability of the Score Scales for the "SAT Reasoning Test"™ from 2005 to 2010. Research Report. ETS RR-12-15

ERIC Educational Resources Information Center

Guo, Hongwen; Liu, Jinghua; Curley, Edward; Dorans, Neil

2012-01-01

This study examines the stability of the "SAT Reasoning Test"™ score scales from 2005 to 2010. A 2005 old form (OF) was administered along with a 2010 new form (NF). A new conversion for OF was derived through direct equipercentile equating. A comparison of the newly derived and the original OF conversions showed that Critical Reading…

easyCBM Beginning Reading Measures: Grades K-1 Alternate Form Reliability and Criterion Validity with the SAT-10. Technical Report #1403

ERIC Educational Resources Information Center

Wray, Kraig; Lai, Cheng-Fei; Sáez, Leilani; Alonzo, Julie; Tindal, Gerald

2013-01-01

We report the results of an alternate form reliability and criterion validity study of kindergarten and grade 1 (N = 84-199) reading measures from the easyCBM© assessment system and Stanford Early School Achievement Test/Stanford Achievement Test, 10th edition (SESAT/SAT-­10) across 5 time points. The alternate form reliabilities ranged from…

Analysis of 2009-10 WCPSS SAT Scores. Measuring Up. E&R Report No. 10.25

ERIC Educational Resources Information Center

Holdzkom, David; Gilleland, Kevin

2010-01-01

Wake County Public School System (WCPSS) students continue to fare well on the SAT test as compared with students in the state and nation. While there was a decline in average test scores in 2009-10 as compared with the prior year, the posted scores continue a trend of measurable improvement over time. Over the past 20 years, the average SAT…

NPS-SCAT: Systems Engineering and Payload Subsystem Design, Integration, and Testing of NPS’ First CubeSat

DTIC Science & Technology

2010-06-01

Subsystem Design, Integration, and Testing of NPS’ First CubeSat 6. AUTHOR(S) Jenkins, Robert D. IV 5. FUNDING NUMBERS 7. PERFORMING ORGANIZATION NAME(S...AND ADDRESS(ES) Naval Postgraduate School Monterey, CA 93943-5000 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING /MONITORING...Experimental Mission SOIC Small Outline Integrated Circuit SOT Small Outline Transistor SpaceX Space Exploration Technologies Corporation SPI

Test-retest reliability and agreement of the Satisfaction with the Assistive Technology Services (SATS) instrument in two Nordic countries.

PubMed

Sund, Terje; Iwarsson, Susanne; Anttila, Heidi; Helle, Tina; Brandt, Ase

2014-07-01

The purpose of this study was to investigate test-retest reliability, agreement, internal consistency, and floor- and ceiling effects of the Danish and Finnish versions of the Satisfaction with the Assistive Technology Services (SATS) instrument among adult users of powered wheelchairs (PWCs) or powered scooters (scooters). Test-retest design, two telephone interviews 7-18 days apart of 40 informants, with mean age of 67.5 (SD 13.09) years in the Danish; and 54 informants with mean age of 55.6 (SD 12.09) years in the Finnish sample. The intra-class correlation coefficient varied between 0.57 and 0.93 for items in the Danish and between 0.41 and 0.93 in the Finnish sample. The percentage agreement varied between 54.2 and 79.5 for items in the Danish and between 69.2 and 81.1 in the Finnish sample, while the Cronbach's alpha values varied between 0.87 and 0.96 in the two samples. A ceiling effect was found in all items of both samples. This study indicates that the SATS may be reliably administered for telephone interviews among adult PWC and scooter users, and give information about aspects of the service delivery process for quality development improvement purposes. Further psychometric testing of the SATS is required.

Small Projects Rapid Integration and Test Environment (SPRITE): Application for Increasing Robustness

NASA Technical Reports Server (NTRS)

Rakoczy, John; Heater, Daniel; Lee, Ashley

2013-01-01

Marshall Space Flight Center's (MSFC) Small Projects Rapid Integration and Test Environment (SPRITE) is a Hardware-In-The-Loop (HWIL) facility that provides rapid development, integration, and testing capabilities for small projects (CubeSats, payloads, spacecraft, and launch vehicles). This facility environment focuses on efficient processes and modular design to support rapid prototyping, integration, testing and verification of small projects at an affordable cost, especially compared to larger type HWIL facilities. SPRITE (Figure 1) consists of a "core" capability or "plant" simulation platform utilizing a graphical programming environment capable of being rapidly re-configured for any potential test article's space environments, as well as a standard set of interfaces (i.e. Mil-Std 1553, Serial, Analog, Digital, etc.). SPRITE also allows this level of interface testing of components and subsystems very early in a program, thereby reducing program risk.

Removal Mechanisms of Para-nitrophenol in Reclaimed Water using SAT and its Bio-enhancement

NASA Astrophysics Data System (ADS)

Wen, Y. L.; Yang, Y.; Zhang, H.; Lou, B.

2017-12-01

Nowadays, we were facing with water resource shortage along with water pollution. It was important to undertake the cost effective technology to treat polluted water whilst encourage water reuse. Soil aquifer treatment (SAT) was an efficient technology, using the infiltration process of mediation, adsorption and biodegradation on the pollutants in the environment to achieve the goal of recycling water. For a better understanding of the transport and attenuation of para-nitrophenol (P-NP) and the change of microbial community at the stress of p-nitrophenol in soil aquifer treatment system, two column experiments were operated to investigate the physical, chemical, and microbial dynamics. At the same time, the bio-augment method was used to enhance the SAT biodegradation system. The SAT column experiment was operated about 38 days, which demonstrated that two reduction zones were revealed at the middle of the column and the biodiversity of the microbial community could be destroyed under the P-NP stress. Absorption was the main removal mechanism according to the obtained experimental data. By using the displacement method, the BIO-SAT system was operated about 36 days, which showed perfect outcome for the P-NP removal at a higher concentration. From the PCR-DGGE and high throughput sequencing study, enhanced bacteria could form a stable biological community with indigenous communities. Through the Canonical Correspondence Analysis (CCA) microbial degradation and environmental factors, the results showed that the pH was a very important parameter affects the degradation of nitrophenol degradation bacteria. The metal ions under the condition of low concentration can promote the growth of microbial degradation. This study provide valuable result on the attenuation potential of for the bio-enhanced SAT system (BIO-SAT). (No Image Selected)

Cancer-linked satellite 2 DNA hypomethylation does not regulate Sat2 non-coding RNA expression and is initiated by heat shock pathway activation.

PubMed

Tilman, Gaëlle; Arnoult, Nausica; Lenglez, Sandrine; Van Beneden, Amandine; Loriot, Axelle; De Smet, Charles; Decottignies, Anabelle

2012-08-01

Epigenetic dysfunctions, including DNA methylation alterations, play major roles in cancer initiation and progression. Although it is well established that gene promoter demethylation activates transcription, it remains unclear whether hypomethylation of repetitive heterochromatin similarly affects expression of non-coding RNA from these loci. Understanding how repetitive non-coding RNAs are transcriptionally regulated is important given that their established upregulation by the heat shock (HS) pathway suggests important functions in cellular response to stress, possibly by promoting heterochromatin reconstruction. We found that, although pericentromeric satellite 2 (Sat2) DNA hypomethylation is detected in a majority of cancer cell lines of various origins, DNA methylation loss does not constitutively hyperactivate Sat2 expression, and also does not facilitate Sat2 transcriptional induction upon heat shock. In melanoma tumor samples, our analysis revealed that the HS response, frequently upregulated in tumors, is probably the main determinant of Sat2 RNA expression in vivo. Next, we tested whether HS pathway hyperactivation may drive Sat2 demethylation. Strikingly, we found that both hyperthermia and hyperactivated RasV12 oncogene, another potent inducer of the HS pathway, reduced Sat2 methylation levels by up to 27% in human fibroblasts recovering from stress. Demethylation occurred locally on Sat2 repeats, resulting in a demethylation signature that was also detected in cancer cell lines with moderate genome-wide hypomethylation. We therefore propose that upregulation of Sat2 transcription in response to HS pathway hyperactivation during tumorigenesis may promote localized demethylation of the locus. This, in turn, may contribute to tumorigenesis, as demethylation of Sat2 was previously reported to favor chromosomal rearrangements.

Lunar and Lagrangian Point L1 L2 CubeSat Communication and Navigation Considerations

NASA Technical Reports Server (NTRS)

Schaire, Scott; Wong, Yen F.; Altunc, Serhat; Bussey, George D.; Shelton, Marta; Folta, Dave; Gramling, Cheryl; Celeste, Peter; Anderson, Mike; Perrotto, Trish;

Extravehicular Activity System Sizing Analysis Tool (EVAS_SAT)

NASA Technical Reports Server (NTRS)

Brown, Cheryl B.; Conger, Bruce C.; Miranda, Bruno M.; Bue, Grant C.; Rouen, Michael N.

2007-01-01

An effort was initiated by NASA/JSC in 2001 to develop an Extravehicular Activity System Sizing Analysis Tool (EVAS_SAT) for the sizing of Extravehicular Activity System (EVAS) architecture and studies. Its intent was to support space suit development efforts and to aid in conceptual designs for future human exploration missions. Its basis was the Life Support Options Performance Program (LSOPP), a spacesuit and portable life support system (PLSS) sizing program developed for NASA/JSC circa 1990. EVAS_SAT estimates the mass, power, and volume characteristics for user-defined EVAS architectures, including Suit Systems, Airlock Systems, Tools and Translation Aids, and Vehicle Support equipment. The tool has undergone annual changes and has been updated as new data have become available. Certain sizing algorithms have been developed based on industry standards, while others are based on the LSOPP sizing routines. The sizing algorithms used by EVAS_SAT are preliminary. Because EVAS_SAT was designed for use by members of the EVA community, subsystem familiarity on the part of the intended user group and in the analysis of results is assumed. The current EVAS_SAT is operated within Microsoft Excel 2003 using a Visual Basic interface system.

Preliminary Analysis of Delta-V Requirements for a Lunar CubeSat Impactor with Deployment Altitude Variations

NASA Astrophysics Data System (ADS)

Song, Young-Joo; Ho, Jin; Kim, Bang-Yeop

2015-09-01

Characteristics of delta-V requirements for deploying an impactor from a mother-ship at different orbital altitudes are analyzed in order to prepare for a future lunar CubeSat impactor mission. A mother-ship is assumed to be orbiting the moon with a circular orbit at a 90 deg inclination and having 50, 100, 150, 200 km altitudes. Critical design parameters that are directly related to the success of the impactor mission are also analyzed including deploy directions, CubeSat flight time, impact velocity, and associated impact angles. Based on derived delta-V requirements, required thruster burn time and fuel mass are analyzed by adapting four different miniaturized commercial onboard thrusters currently developed for CubeSat applications. As a result, CubeSat impact trajectories as well as thruster burn characteristics deployed at different orbital altitudes are found to satisfy the mission objectives. It is concluded that thrust burn time should considered as the more critical design parameter than the required fuel mass when deducing the onboard propulsion system requirements. Results provided through this work will be helpful in further detailed system definition and design activities for future lunar missions with a CubeSat-based payload.

Identification of aaNAT5b as a spermine N-acetyltransferase in the mosquito, Aedes aegypti.

PubMed

Guan, Huai; Wang, Maoying; Liao, Chenghong; Liang, Jing; Mehere, Prajwalini; Tian, Meiling; Liu, Hairong; Robinson, Howard; Li, Jianyong; Han, Qian

2018-01-01

Mosquitoes transmit a number of diseases in animals and humans, including Dengue, Chikungunya and Zika viruses that affect millions of people each year. Controlling the disease-transmitting mosquitoes has proven to be a successful strategy to reduce the viruses transmission. Polyamines are required for the life cycle of the RNA viruses, Chikungunya virus and Zika virus, and a depletion of spermidine and spermine in the host via induction of spermine N-acetyltransferase restricts their replication. Spermine N-acetyltransferase is a key catabolic enzyme in the polyamine pathway, however there is no information of the enzyme identification in any insects. Aliphatic polyamines play a fundamental role in tissue growth and development in organisms. They are acetylated by spermidine/spermine N1-acetyltransferase (SAT). In this study we provided a molecular and biochemical identification of SAT from Aedes aegypti mosquitoes. Screening of purified recombinant proteins against polyamines established that aaNAT5b, named previously based on sequence similarity with identified aaNAT1 in insects, is active to spermine and spermidine. A crystal structure was determined and used in molecular docking in this study. Key residues were identified to be involved in spermine binding using molecular docking and simulation. In addition, SAT transcript was down regulated by blood feeding using a real time PCR test. Based on its substrate profile and transcriptional levels after blood feeding, together with previous reports for polyamines required in arboviruses replication, SAT might be potentially used as a target to control arboviruses with human interference.

Tactically Extensible and Modular Communications - X-Band TEMCOM-X

NASA Technical Reports Server (NTRS)

Sims, William Herbert; Varnavas, Kosta A.; Casas, Joseph; Spehn, Stephen L.; Kendrick, Neal; Cross, Stephen; Sanderson, Paul; Booth, Janet C.

2015-01-01

This paper will discuss a proposed CubeSat size (3U) telemetry system concept being developed at Marshall Space Flight Center (MSFC) in cooperation with the U.S. Department of the Army and Dynetics Corporation. This telemetry system incorporates efficient, high-bandwidth communications by developing flight-ready, low-cost, Protoflight software defined radio (SDR) and Electronically Steerable Patch Array (ESPA) antenna subsystems for use on platforms as small as CubeSats and unmanned aircraft systems (UASs). The current telemetry system is slightly larger in dimension of footprint than required to fit within a 0.5U CubeSat volume. Extensible and modular communications for CubeSat technologies will partially mitigate current capability gaps between traditional strategic space platforms and lower-cost small satellite solutions. Higher bandwidth capacity will enable high-volume, low error-rate data transfer to and from tactical forces or sensors operating in austere locations (e.g., direct imagery download, unattended ground sensor data exfiltration, interlink communications), while also providing additional bandwidth and error correction margin to accommodate more complex encryption algorithms and higher user volume.

Considerations in the Integration of Small Aircraft Transportation System Higher Volume Operations (SATSHVO) in the National Airspace System (NAS)

NASA Technical Reports Server (NTRS)

Lohr, Gary W.; Williams, Dan; Abbott, Terence; Baxley, Brian; Greco, Adam; Ridgway, Richard

2005-01-01

The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) concept holds the promise for increased efficiency and throughput at many of the nations under-used airports. This concept allows for concurrent operations at uncontrolled airports that under today s procedures are restricted to one arrival or one departure operation at a time, when current-day IFR separation standards are applied. To allow for concurrent operations, SATS HVO proposes several fundamental changes to today's system. These changes include: creation of dedicated airspace, development of new procedures and communications (phraseologies), and assignment of roles and responsibilities for pilots and controllers, among others. These changes would affect operations on the airborne side (pilot) as well as the groundside (controller and air traffic flow process). The focus of this paper is to discuss some of the issues and potential problems that have been considered in the development of the SATS HVO concept, in particular from the ground side perspective. Reasonable solutions to the issues raised here have been proposed by the SATS HVO team, and are discussed in this paper.

SmallSats, Iodine Propulsion Technology, Applications to Low-Cost Lunar Missions, and the Iodine Satellite (iSAT) Project

NASA Technical Reports Server (NTRS)

Dankanich, John W.

2014-01-01

Closing Remarks: ?(1) SmallSats hold significant potential for future low cost high value missions; (2) Propulsion remains a key limiting capability for SmallSats that Iodine can address: High ISP * Density for volume constrained spacecraft; Indefinite quiescence, unpressurized and non-hazardous as a secondary payload; (3) Iodine enables MicroSat and SmallSat maneuverability: Enables transfer into high value orbits, constellation deployment and deorbit; (4) Iodine may enable a new class of planetary and exploration class missions: Enables GTO launched secondary spacecraft to transit to the moon, asteroids, and other interplanetary destinations for approximately 150 million dollars full life cycle cost including the launch; (5) ESPA based OTVs are also volume constrained and a shift from xenon to iodine can significantly increase the transfer vehicle change in volume capability including transfers from GTO to a range of Lunar Orbits; (6) The iSAT project is a fast pace high value iodine Hall technology demonstration mission: Partnership with NASA GRC and NASA MSFC with industry partner - Busek; (7) The iSAT mission is an approved project with PDR in November of 2014 and is targeting a flight opportunity in FY17.

An Assessment of the Dimensionality of SAT-Mathematical.

ERIC Educational Resources Information Center

Lawrence, Ida M.; Dorans, Neil J.

Six editions of Scholastic Aptitude Test-Mathematical (SAT-M) were factor analyzed using confirmatory and exploratory methods. Confirmatory factor analyses (using the LISREL VI program) were conducted on correlation matrices among item parcels--sums of scores on a small subset of items. Item parcels were constructed to yield correlation matrices…

Unflagged SATs: Who Benefits from Special Accommodations?

ERIC Educational Resources Information Center

Abrams, Samuel J.

2005-01-01

When the College Board announced, in the summer of 2002, that it would stop "flagging" the test scores of students who were given special accommodations for the SAT, the gold standard exam for college admission, disability advocates were thrilled. "A triumphant day for millions of people with dyslexia and other disabilities,"…

Achieving Science with CubeSats: Thinking Inside the Box

NASA Astrophysics Data System (ADS)

Zurbuchen, Thomas H.; Lal, Bhavya

2017-01-01

We present the results of a study conducted by the National Academies of Sciences, Engineering, and Medicine. The study focused on the scientific potential and technological promise of CubeSats. We will first review the growth of the CubeSat platform from an education-focused technology toward a platform of importance for technology development, science, and commercial use, both in the United States and internationally. The use has especially exploded in recent years. For example, of the over 400 CubeSats launched since 2000, more than 80% of all science-focused ones have been launched just in the past four years. Similarly, more than 80% of peer-reviewed papers describing new science based on CubeSat data have been published in the past five years.We will then assess the technological and science promise of CubeSats across space science disciplines, and discuss a subset of priority science goals that can be achieved given the current state of CubeSat capabilities. Many of these goals address targeted science, often in coordination with other spacecraft, or by using sacrificial or high-risk orbits that lead to the demise of the satellite after critical data have been collected. Other goals relate to the use of CubeSats as constellations or swarms, deploying tens to hundreds of CubeSats that function as one distributed array of measurements.Finally, we will summarize our conclusions and recommendations from this study; especially those focused on nearterm investment that could improve the capabilities of CubeSats toward increased science and technological return and enable the science communities’ use of CubeSats.

Achieving Science with CubeSats: Thinking Inside the Box

NASA Astrophysics Data System (ADS)

Lal, B.; Zurbuchen, T.

2016-12-01

In this paper, we present a study conducted by the National Academies of Sciences, Engineering, and Medicine. The study focused on the scientific potential and technological promise of CubeSats. We will first review the growth of the CubeSat platform from an education-focused technology toward a platform of importance for technology development, science, and commercial use, both in the United States and internationally. The use has especially exploded in recent years. For example, of the over 400 CubeSats launched since 2000, more than 80% of all science-focused ones have been launched just in the past four years. Similarly, more than 80% of peer-reviewed papers describing new science based on CubeSat data have been published in the past five years. We will then assess the technological and science promise of CubeSats across space science disciplines, and discuss a subset of priority science goals that can be achieved given the current state of CubeSat capabilities. Many of these goals address targeted science, often in coordination with other spacecraft, or by using sacrificial or high-risk orbits that lead to the demise of the satellite after critical data have been collected. Other goals relate to the use of CubeSats as constellations or swarms, deploying tens to hundreds of CubeSats that function as one distributed array of measurements. Finally, we will summarize our conclusions and recommendations from this study; especially those focused on near-term investment that could improve the capabilities of CubeSats toward increased science and technological return and enable the science communities' use of CubeSats.

State-of-the-Art for Small Satellite Propulsion Systems

NASA Technical Reports Server (NTRS)

Parker, Khary I.

2016-01-01

The NASA/Goddard Space Flight Center (NASA/GSFC) is in the business of performing world-class, space-based, scientific research on various spacecraft platforms, which now include small satellites (SmallSats). In order to perform world class science on a SmallSat, NASA/GSFC requires that their components be highly reliable, high performing, have low power consumption, at the lowest cost possible. The Propulsion Branch (Code 597) at NASA/GSFC has conducted a SmallSat propulsion system survey to determine their availability and level of development. Based on publicly available information and unique features, this paper discusses some of the existing SmallSat propulsion systems.. The systems described in this paper do not indicate or imply any endorsement by NASA or NASA/GSFC over those not included.

Range Environmental Assessment for Test Area C-52 Complex, Eglin Air Force Base, Florida

DTIC Science & Technology

2014-10-31

tourism in the region. Promotes and develops general business, trade, and tourism components of the state economy. Chapter 334 Transportation...sale in BWB. 124 Canterbury Circle. Sat. Aug. 23rd, 8am-2pm. Sports equip, house- wares, books, puzzles, linens, glassware, all must go! Indoor sale

A SAT Based Effective Algorithm for the Directed Hamiltonian Cycle Problem

NASA Astrophysics Data System (ADS)

Jäger, Gerold; Zhang, Weixiong

The Hamiltonian cycle problem (HCP) is an important combinatorial problem with applications in many areas. While thorough theoretical and experimental analyses have been made on the HCP in undirected graphs, little is known for the HCP in directed graphs (DHCP). The contribution of this work is an effective algorithm for the DHCP. Our algorithm explores and exploits the close relationship between the DHCP and the Assignment Problem (AP) and utilizes a technique based on Boolean satisfiability (SAT). By combining effective algorithms for the AP and SAT, our algorithm significantly outperforms previous exact DHCP algorithms including an algorithm based on the award-winning Concorde TSP algorithm.

VZLUSAT-1: Nanosatellite with miniature lobster eye X-ray telescope and qualification of the radiation shielding composite for space application

NASA Astrophysics Data System (ADS)

Urban, Martin; Nentvich, Ondrej; Stehlikova, Veronika; Baca, Tomas; Daniel, Vladimir; Hudec, Rene

2017-11-01

In the upcoming generation of small satellites there is a great potential for testing new sensors, processes and technologies for space and also for the creation of large in situ sensor networks. It plays a significant role in the more detailed examination, modelling and evaluation of the orbital environment. Scientific payloads based on the CubeSat technology are also feasible and the miniature X-ray telescope described in this paper may serve as an example. One of these small satellites from CubeSat family is a Czech CubeSat VZLUSAT-1, which is going to be launched during QB50 mission in 2017. This satellite has dimensions of 100 mm × 100 mm × 230 mm. The VZLUSAT-1 has three main payloads. The tested Radiation Hardened Composites Housing (RHCH) has ambitions to be used as a structural and shielding material to protect electronic devices in space or for constructions of future manned and unmanned spacecraft as well as Moon or Martian habitats. The novel miniaturized X-ray telescope with a Lobster Eye (LE) optics represents an example of CubeSat's scientific payload. The telescope has a wide field of view and such systems may be essential in detecting the X-ray sources of various physical origin. VZLUSAT-1 also carries the FIPEX payload which measures the molecular and atomic oxygen density among part of the satellite group in QB50 mission. The VZLUSAT-1 is one of the constellation in the QB50 mission that create a measuring network around the Earth and provide multipoint, in-situ measurements of the atmosphere.

Using Additive Manufacturing to Print a CubeSat Propulsion System

NASA Technical Reports Server (NTRS)

Marshall, William M.

2015-01-01

CubeSats are increasingly being utilized for missions traditionally ascribed to larger satellites CubeSat unit (1U) defined as 10 cm x 10 cm x 11 cm. Have been built up to 6U sizes. CubeSats are typically built up from commercially available off-the-shelf components, but have limited capabilities. By using additive manufacturing, mission specific capabilities (such as propulsion), can be built into a system. This effort is part of STMD Small Satellite program Printing the Complete CubeSat. Interest in propulsion concepts for CubeSats is rapidly gaining interest-Numerous concepts exist for CubeSat scale propulsion concepts. The focus of this effort is how to incorporate into structure using additive manufacturing. End-use of propulsion system dictates which type of system to develop-Pulse-mode RCS would require different system than a delta-V orbital maneuvering system. Team chose an RCS system based on available propulsion systems and feasibility of printing using a materials extrusion process. Initially investigated a cold-gas propulsion system for RCS applications-Materials extrusion process did not permit adequate sealing of part to make this a functional approach.

Biofeedback-based self-alert training reduces alpha activity and stabilizes accuracy in the Sustained Attention to Response Task.

PubMed

Braun, Niclas; Debener, Stefan; Sölle, Ariane; Kranczioch, Cornelia; Hildebrandt, Helmut

2015-01-01

Deficits in sustaining attention are common in various organic brain diseases. A recent study proposed self-alert training (SAT) as a technique to improve sustained attention. In the SAT, individuals learn to gain volitional control over their own state of arousal by means of electrodermal biofeedback. In this study, we investigated the behavioral, electrodermal, and electroencephalogram correlates of the SAT with a blinded, randomized, and active-controlled pre-post study design. Sustained attention capacity was assessed with the Sustained Attention to Response Task (SART). The SAT resulted in strong phasic increases in skin conductance response (SCR), but endogenous control of SCR without feedback was problematic. Electroencephalogram analysis revealed stronger alpha reduction during SART for the SAT than for the control group. Behaviorally, the SAT group performed more accurately and more slowly after intervention than the control group. The study provides further evidence that SAT helps to maintain SART accuracy over prolonged periods of time. Whether this accuracy is more related to sustained attention or response inhibition is discussed.

Adaptive fuzzy logic controller with direct action type structures for InnoSAT attitude control system

NASA Astrophysics Data System (ADS)

Bakri, F. A.; Mashor, M. Y.; Sharun, S. M.; Bibi Sarpinah, S. N.; Abu Bakar, Z.

2016-10-01

This study proposes an adaptive fuzzy controller for attitude control system (ACS) of Innovative Satellite (InnoSAT) based on direct action type structure. In order to study new methods used in satellite attitude control, this paper presents three structures of controllers: Fuzzy PI, Fuzzy PD and conventional Fuzzy PID. The objective of this work is to compare the time response and tracking performance among the three different structures of controllers. The parameters of controller were tuned on-line by adjustment mechanism, which was an approach similar to a PID error that could minimize errors between actual and model reference output. This paper also presents a Model References Adaptive Control (MRAC) as a control scheme to control time varying systems where the performance specifications were given in terms of the reference model. All the controllers were tested using InnoSAT system under some operating conditions such as disturbance, varying gain, measurement noise and time delay. In conclusion, among all considered DA-type structures, AFPID controller was observed as the best structure since it outperformed other controllers in most conditions.

Reconstruction of regional mean temperature for East Asia since 1900s and its uncertainties

NASA Astrophysics Data System (ADS)

Hua, W.

2017-12-01

Regional average surface air temperature (SAT) is one of the key variables often used to investigate climate change. Unfortunately, because of the limited observations over East Asia, there were also some gaps in the observation data sampling for regional mean SAT analysis, which was important to estimate past climate change. In this study, the regional average temperature of East Asia since 1900s is calculated by the Empirical Orthogonal Function (EOF)-based optimal interpolation (OA) method with considering the data errors. The results show that our estimate is more precise and robust than the results from simple average, which provides a better way for past climate reconstruction. In addition to the reconstructed regional average SAT anomaly time series, we also estimated uncertainties of reconstruction. The root mean square error (RMSE) results show that the the error decreases with respect to time, and are not sufficiently large to alter the conclusions on the persist warming in East Asia during twenty-first century. Moreover, the test of influence of data error on reconstruction clearly shows the sensitivity of reconstruction to the size of the data error.

Phonesat In-flight Experience Results

NASA Technical Reports Server (NTRS)

Attai, Watson; Guillen, Salas Alberto; Oyadomari, Ken Yuji; Priscal, Cedric; Shimmin, Rogan Stuart; Gazulla, Oriol Tintore; Wolfe, Jasper Lewis

2014-01-01

Consumer technology, over the last decade, has begun to encompass devices that enable us to figure out where we are, which way we are pointing, observe the world around us, and store and transmit this information to wherever we want. Once separate consumer products such as GPS units, digital cameras and mobile phones are now combined into the modern day Smartphone. Since these capabilities are remarkably similar to those required for the multi-million dollar satellites - so why not use a multihundred dollar Smartphone instead? The PhoneSat project of NASA Ames Research Center is developing technology demonstrations utilizing these extraordinary advances to show just how simple and cheap Space can be. The style of development revolves around the "release early, release often" Silicon Valley mentality. PhoneSat is a series of 1U CubeSat size spacecrafts that use an off-the-shelf Smartphone as their onboard computer. By doing so, PhoneSat takes advantage of the high computational capability, large memory as well as ultra-tiny sensors like high-resolution cameras and navigation devices that Smartphones offer. Along with a Smartphone, PhoneSat is equipped with other commercially available technology products, such as medical brushless motors that are used as reaction wheels. Over the four years that NASA Ames Research Center has been developing the PhoneSat project, different suborbital and orbital flight activities have proven the validity of this revolutionary approach. In early 2013, the PhoneSat project launched the first triage of PhoneSats into LEO. In the five day orbital life time, the nano-satellites flew the first functioning Smartphone based satellites (using the Nexus One and Nexus S phones), the cheapest satellite (a total parts cost below $3,500) and one of the fastest on-board processors (CPU speed of 1GHz). In late 2013, the PhoneSat project launched an improved version of its bus to a higher altitude orbit which provided data about the overall system's tolerance to the space environment. In this paper, an overview of the PhoneSat project as well as a summary of the in-flight experimental results is presented. NASA Ames Research Center is carrying on its effort to bring a paradigm shift in the way we conceive Space exploration, this new approach is certainly incarnated by PhoneSat. A set of eight PhoneSat-based CubeSats is manifested to launch in 2014 with the purpose of demonstrating new technical capabilities and being a pathfinder for future Spacecraft technology missions.

Extended-range forecasting of Chinese summer surface air temperature and heat waves

NASA Astrophysics Data System (ADS)

Zhu, Zhiwei; Li, Tim

2018-03-01

Because of growing demand from agricultural planning, power management and activity scheduling, extended-range (5-30-day lead) forecasting of summer surface air temperature (SAT) and heat waves over China is carried out in the present study via spatial-temporal projection models (STPMs). Based on the training data during 1960-1999, the predictability sources are found to propagate from Europe, Northeast Asia, and the tropical Pacific, to influence the intraseasonal 10-80 day SAT over China. STPMs are therefore constructed using the projection domains, which are determined by these previous predictability sources. For the independent forecast period (2000-2013), the STPMs can reproduce EOF-filtered 30-80 day SAT at all lead times of 5-30 days over most part of China, and observed 30-80 and 10-80 day SAT at 25-30 days over eastern China. Significant pattern correlation coefficients account for more than 50% of total forecasts at all 5-30-day lead times against EOF-filtered and observed 30-80 day SAT, and at a 20-day lead time against observed 10-80 day SAT. The STPMs perform poorly in reproducing 10-30 day SAT. Forecasting for the first two modes of 10-30 day SAT only shows useful skill within a 15-day lead time. Forecasting for the third mode of 10-30 day SAT is useless after a 10-day lead time. The forecasted heat waves over China are determined by the reconstructed SAT which is the summation of the forecasted 10-80 day SAT and the lower frequency (longer than 80-day) climatological SAT. Over a large part of China, the STPMs can forecast more than 30% of heat waves within a 15-day lead time. In general, the STPMs demonstrate the promising skill for extended-range forecasting of Chinese summer SAT and heat waves.

Flight Testing of a Low Cost De-Orbiting Device for Small Satellites

NASA Technical Reports Server (NTRS)

Turse, Dana; Keller, Phil; Taylor, Robert; Reavis, Mark; Tupper, Mike; Koehler, Chris

2014-01-01

Use of small and very small spacecraft is rapidly becoming more common. Methods to intentionally deorbit these spacecraft at the end of useful satellite life are required. A family of mass efficient Roll-Out De- Orbiting devices (RODEO"TM") was developed by Composite Technology Development, Inc. (CTD). RODEO"TM" consists of lightweight film attached to a simple, ultra-lightweight, roll-out composite boom structure. This system is rolled to stow within a lightweight launch canister, allowing easy integration to the small satellite bus. The device is released at the end of useful lifetime and the RODEO"TM" composite boom unrolls the drag sail in a matter of seconds. This dramatically increases the deployed surface area, resulting in the higher aerodynamic drag that significantly reduces the time until reentry. A RODEO"TM" flight demonstration was recently conducted as part of the Colorado Space Grant Consortium's (COSGC) RocketSat-8 program, a program to provide students hands-on experience in developing experiments for space flight. The experiment was ultimately a success and RODEO (trademark) is now ready for future CubeSat missions.

Suppressive antibiotic therapy with oral doxycycline for Staphylococcus aureus prosthetic joint infection: a retrospective study of 39 patients.

PubMed

Pradier, M; Nguyen, S; Robineau, O; Titecat, M; Blondiaux, N; Valette, M; Loïez, C; Beltrand, E; Dézeque, H; Migaud, H; Senneville, E

2017-09-01

The aim of this study was to describe the use of oral doxycycline as suppressive antibiotic therapy (SAT) in patients with Staphylococcus aureus periprosthetic (hip or knee) joint infections. The medical charts of all patients with surgical revisions for S. aureus hip or knee prosthetic joint infections (PJIs) who were given doxycycline-based SAT because of a high risk of failure of various origins were reviewed. Data regarding tolerability and effectiveness of doxycycline-based SAT were analysed. A total of 39 patients (mean age 66.1 ± 16.3 years) received doxycycline-base SAT in the period from January 2006 to January 2014. PJIs involved the hip in 23 patients (59.0%) and the knee in 16 (41.0%), and were qualified as early in 15 patients (38.5%). Methicillin-resistant S. aureus (MRSA) accounted for 22% of the total number of bacterial strains identified. All patients included in the study had surgery, which consisted of debridement and implant retention in 32 (82.1%). Adverse events likely attributable to SAT were reported in six patients (15.4%), leading to discontinuation of SAT in three (7.7%). A total of 29 patients (74.4%) remained event-free and 10 (25.6%) failed, including 8 (20.5%) relapses and 2 (5.1%) superinfections. Overall, 8 of the 10 failure cases were related to a doxycycline-susceptible pathogen. These results suggest that oral doxycycline used as SAT in patients treated for S. aureus hip or knee PJIs has an acceptable tolerability and effectiveness and appears to be a reasonable option in this setting. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Young drivers' engagement with social interactive technology on their smartphone: Critical beliefs to target in public education messages.

PubMed

Gauld, Cassandra S; Lewis, Ioni M; White, Katherine M; Watson, Barry

2016-11-01

The current study forms part of a larger study based on the Step Approach to Message Design and Testing (SatMDT), a new and innovative framework designed to guide the development and evaluation of health communication messages, including road safety messages. This four step framework is based on several theories, including the Theory of Planned Behaviour. The current study followed steps one and two of the SatMDT framework and utilised a quantitative survey to validate salient beliefs (behavioural, normative, and control) about initiating, monitoring/reading, and responding to social interactive technology on smartphones by N=114 (88F, 26M) young drivers aged 17-25 years. These beliefs had been elicited in a prior in-depth qualitative study. A subsequent critical beliefs analysis identified seven beliefs as potential targets for public education messages, including, 'slow-moving traffic' (control belief - facilitator) for both monitoring/reading and responding behaviours; 'feeling at ease that you had received an expected communication' (behavioural belief -advantage) for monitoring/reading behaviour; and 'friends/peers more likely to approve' (normative belief) for responding behaviour. Potential message content targeting these seven critical beliefs is discussed in accordance with the SatMDT. Copyright © 2016 Elsevier Ltd. All rights reserved.

Design of a Representative Low Earth Orbit Satellite to Improve Existing Debris Models

NASA Technical Reports Server (NTRS)

Clark, S.; Dietrich, A.; Werremeyer, M.; Fitz-Coy, N.; Liou, J.-C.

2012-01-01

This paper summarizes the process and methodologies used in the design of a small-satellite, DebriSat, that represents materials and construction methods used in modern day Low Earth Orbit (LEO) satellites. This satellite will be used in a future hypervelocity impact test with the overall purpose to investigate the physical characteristics of modern LEO satellites after an on-orbit collision. The major ground-based satellite impact experiment used by DoD and NASA in their development of satellite breakup models was conducted in 1992. The target used for that experiment was a Navy Transit satellite (40 cm, 35 kg) fabricated in the 1960 s. Modern satellites are very different in materials and construction techniques from a satellite built 40 years ago. Therefore, there is a need to conduct a similar experiment using a modern target satellite to improve the fidelity of the satellite breakup models. The design of DebriSat will focus on designing and building a next-generation satellite to more accurately portray modern satellites. The design of DebriSat included a comprehensive study of historical LEO satellite designs and missions within the past 15 years for satellites ranging from 10 kg to 5000 kg. This study identified modern trends in hardware, material, and construction practices utilized in recent LEO missions, and helped direct the design of DebriSat.

Directly administered antiretroviral therapy for HIV-infected drug users does not have an impact on antiretroviral resistance: results from a randomized controlled trial.

PubMed

Maru, Duncan Smith-Rohrberg; Kozal, Michael J; Bruce, R Douglas; Springer, Sandra A; Altice, Frederick L

2007-12-15

Directly administered antiretroviral therapy (DAART) is an effective intervention that improves clinical outcomes among HIV-infected drug users. Its effects on antiretroviral drug resistance, however, are unknown. We conducted a community-based, prospective, randomized controlled trial of DAART compared with self-administered therapy (SAT). We performed a modified intention-to-treat analysis among 115 subjects who provided serum samples for HIV genotypic resistance testing at baseline and at follow-up. The main outcomes measures included total genotypic sensitivity score, future drug options, number of new drug resistance mutations (DRMs), and number of new major International AIDS Society (IAS) mutations. The adjusted probability of developing at least 1 new DRM did not differ between the 2 arms (SAT: 0.41 per person-year [PPY], DAART: 0.49 PPY; adjusted relative risk [RR] = 1.04; P = 0.90), nor did the number of new mutations (SAT: 0.76 PPY, DAART: 0.83 PPY; adjusted RR = 0.99; P = 0.99) or the probability of developing new major IAS new drug mutations (SAT: 0.30 PPY, DAART: 0.33 PPY; adjusted RR = 1.12; P = 0.78). On measures of GSS and FDO, the 2 arms also did not differ. In this trial, DAART provided on-treatment virologic benefit for HIV-infected drug users without affecting the rate of development of antiretroviral medication resistance.

Lightweight Inflatable Solar Array: Providing a Flexible, Efficient Solution to Space Power Systems for Small Spacecraft

NASA Technical Reports Server (NTRS)

Johnson, Les; Fabisinski, Leo; Justice, Stefanie

2014-01-01

Affordable and convenient access to electrical power is critical to consumers, spacecraft, military and other applications alike. In the aerospace industry, an increased emphasis on small satellite flights and a move toward CubeSat and NanoSat technologies, the need for systems that could package into a small stowage volume while still being able to power robust space missions has become more critical. As a result, the Marshall Space Flight Center's Advanced Concepts Office identified a need for more efficient, affordable, and smaller space power systems to trade in performing design and feasibility studies. The Lightweight Inflatable Solar Array (LISA), a concept designed, prototyped, and tested at the NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama provides an affordable, lightweight, scalable, and easily manufactured approach for power generation in space or on Earth. This flexible technology has many wide-ranging applications from serving small satellites to soldiers in the field. By using very thin, ultraflexible solar arrays adhered to an inflatable structure, a large area (and thus large amount of power) can be folded and packaged into a relatively small volume (shown in artist rendering in Figure 1 below). The proposed presentation will provide an overview of the progress to date on the LISA project as well as a look at its potential, with continued development, to revolutionize small spacecraft and portable terrestrial power systems.

Propulsion Technology Demonstrator. [Demonstrating Novel CubeSat Technologies in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Marmie, John; Martinez, Andres; Petro, Andrew

2015-01-01

NASA's Pathfinder Technology Demonstrator (PTD) project will test the operation of a variety of novel CubeSat technologies in low- Earth orbit, providing significant enhancements to the performance of these small and effective spacecraft. Each Pathfinder Technology Demonstrator mission consists of a 6-unit (6U) CubeSat weighing approximately 26 pounds (12 kilograms) and measuring 12 inches x 10 inches x 4 inches (30 centimeters x 25 centimeters x 10 centimeters), comparable in size to a common shoebox. CubeSats are a class of nanosatellites that use a standard size and form factor. The standard Cube- Sat size uses a "one unit" or "1U" measuring 4 inches x 4 inches x 4 inches (10x10x10 centimeters) and is extendable to larger sizes by "stacking" a number of the 1U blocks to form a larger spacecraft. Each PTD spacecraft will also be equipped with deployable solar arrays that provide an average of 44 watts of power while in orbit.

What's the Cube Quest Challenge?

NASA Technical Reports Server (NTRS)

Cockrell, Jim

2016-01-01

Cube Quest Challenge, sponsored by Space Technology Mission Directorates Centennial Challenges program, is NASAs first in-space prize competition. Cube Quest is open to any U.S.-based, non-government CubeSat developer. Entrants will compete for one of three available 6U CubeSat dispenser slots on the EM-1 mission the first un-crewed lunar flyby of the Orion spacecraft launched by the Space Launch System in early 2018. The Cube Quest Challenge will award up to $5M in prizes. The advanced CubeSat technologies demonstrated by Cube Quest winners will enable NASA, universities, and industry to more quickly and affordably accomplish science and exploration objectives. This paper describes the teams, their novel CubeSat designs, and the emerging technologies for CubeSat operations in deep space environment.

Relationship between Air Traffic Selection and Training (AT-SAT)) Battery Test Scores and Composite Scores in the Initial en Route Air Traffic Control Qualification Training Course at the Federal Aviation Administration (FAA) Academy

ERIC Educational Resources Information Center

Kelley, Ronald Scott

2012-01-01

Scope and Method of Study: This study focused on the development and use of the AT-SAT test battery and the Initial En Route Qualification training course for the selection, training, and evaluation of air traffic controller candidates. The Pearson product moment correlation coefficient was used to measure the linear relationship between the…

Psychometric and Edumetric Validity of Dimensions of Geomorphological Knowledge Which Are Tapped by Concept Mapping.

ERIC Educational Resources Information Center

Hoz, Ron; Bowman, Dan; Chacham, Tova

1997-01-01

Students (N=14) in a geomorphology course took an objective geomorphology test, the tree construction task, and the Standardized Concept Structuring Analysis Technique (SConSAT) version of concept mapping. Results suggest that the SConSAT knowledge structure dimensions have moderate to good construct validity. Contains 82 references. (DDR)

Predicting College Performance of American Indians: A Large-Sample Examination of the SAT

ERIC Educational Resources Information Center

Shu, Siwen; Kuncel, Nathan R.; Sackett, Paul R.

2017-01-01

Extensive research has examined the validity and fairness of standardized tests in academic admissions. However, due to their underrepresentation in higher education, American Indians have gained much less attention in this research. In the present study, we examined for American Indian students (1) group differences on SAT scores, (2) the…

Academic Profile of 1983 Maryland College-Bound Seniors.

ERIC Educational Resources Information Center

Maryland State Board for Higher Education, Annapolis.

Information is presented on Scholastic Aptitude Test (SAT) performance of Maryland high school seniors who graduated in 1983, and characteristics of the students are examined. Of the 29,755 Maryland students who took the SAT in 1983, 18 percent were black, 20 percent attended nonpublic schools, and 53 percent were females. Maryland seniors…

Interplanetary Radiation and Fault Tolerant Mini-Star Tracker System

NASA Technical Reports Server (NTRS)

Rakoczy, John; Paceley, Pete

2015-01-01

The Charles Stark Draper Laboratory, Inc. is partnering with the NASA Marshall Space Flight Center (MSFC) Engineering Directorate's Avionics Design Division and Flight Mechanics & Analysis Division to develop and test a prototype small, low-weight, low-power, radiation-hardened, fault-tolerant mini-star tracker (fig. 1). The project is expected to enable Draper Laboratory and its small business partner, L-1 Standards and Technologies, Inc., to develop a new guidance, navigation, and control sensor product for the growing small sat technology market. The project also addresses MSFC's need for sophisticated small sat technologies to support a variety of science missions in Earth orbit and beyond. The prototype star tracker will be tested on the night sky on MSFC's Automated Lunar and Meteor Observatory (ALAMO) telescope. The specific goal of the project is to address the need for a compact, low size, weight, and power, yet radiation hardened and fault tolerant star tracker system that can be used as a stand-alone attitude determination system or incorporated into a complete attitude determination and control system for emerging interplanetary and operational CubeSat and small sat missions.

The Academic Success of East Asian American Youth: The Role of Shadow Education

PubMed Central

Byun, Soo-yong; Park, Hyunjoon

2013-01-01

Using data from the Education Longitudinal Study, this study assessed the relevance of shadow education to the high academic performance of East Asian American students by examining how East Asian American students differed from other racial/ethnic students in the prevalence, purpose, and effects of using the two forms – commercial test preparation service and private one-to-one tutoring – of SAT coaching, defined as the American style of shadow education. East Asian American students were most likely to take a commercial SAT test preparation course for the enrichment purpose, and benefited most from taking this particular form of SAT coaching. However, this was not the case for private SAT one-to-one tutoring. While black students were most likely to utilize private tutoring for the remedial purpose, the impact of private tutoring was trivial for all racial/ethnic groups including East Asian American students. The authors discussed broader implications of the findings on racial/ethnic inequalities in educational achievement beyond the relevance of shadow education for the academic success of East Asian American students. PMID:24163483

Massively Clustered CubeSats NCPS Demo Mission

NASA Technical Reports Server (NTRS)

Robertson, Glen A.; Young, David; Kim, Tony; Houts, Mike

2013-01-01

Technologies under development for the proposed Nuclear Cryogenic Propulsion Stage (NCPS) will require an un-crewed demonstration mission before they can be flight qualified over distances and time frames representative of a crewed Mars mission. In this paper, we describe a Massively Clustered CubeSats platform, possibly comprising hundreds of CubeSats, as the main payload of the NCPS demo mission. This platform would enable a mechanism for cost savings for the demo mission through shared support between NASA and other government agencies as well as leveraged commercial aerospace and academic community involvement. We believe a Massively Clustered CubeSats platform should be an obvious first choice for the NCPS demo mission when one considers that cost and risk of the payload can be spread across many CubeSat customers and that the NCPS demo mission can capitalize on using CubeSats developed by others for its own instrumentation needs. Moreover, a demo mission of the NCPS offers an unprecedented opportunity to invigorate the public on a global scale through direct individual participation coordinated through a web-based collaboration engine. The platform we describe would be capable of delivering CubeSats at various locations along a trajectory toward the primary mission destination, in this case Mars, permitting a variety of potential CubeSat-specific missions. Cameras on various CubeSats can also be used to provide multiple views of the space environment and the NCPS vehicle for video monitoring as well as allow the public to "ride along" as virtual passengers on the mission. This collaborative approach could even initiate a brand new Science, Technology, Engineering and Math (STEM) program for launching student developed CubeSat payloads beyond Low Earth Orbit (LEO) on future deep space technology qualification missions. Keywords: Nuclear Propulsion, NCPS, SLS, Mars, CubeSat.

A Comparison of the SOCIT and DebriSat Experiments

NASA Technical Reports Server (NTRS)

Ausay, E.; Cornejo, A.; Horn, A.; Palma, K.; Sato, T.; Blake, B.; Pistella, F.; Boyle, C.; Todd, N.; Zimmerman, J.;

Transformation and speciation of typical heavy metals in soil aquifer treatment system during long time recharging with secondary effluent: Depth distribution and combination.

PubMed

Wei, Liangliang; Wang, Kun; Noguera, Daniel R; Jiang, Junqiu; Oyserman, Ben; Zhao, Ningbo; Zhao, Qingliang; Cui, Fuyi

2016-12-01

Soil aquifer treatment (SAT) systems rely on extensive physical and biogeochemical processes in the vadose zone and aquifer for water quality improvement. In this study, the distribution, quantitative changes, as well as the speciation characteristics of heavy metals in different depth of soils of a two-year operated lab-scale SAT was explored. A majority of the heavy metals in the recharged secondary effluent were efficiently trapped by the steady-state operated SAT (removal efficiency ranged from 74.7% to 98.2%). Thus, significant accumulations of 31.7% for Cd, 15.9% for Cu, 15.3% for Zn and 8.6% for Cr were observed for the top soil after 730 d operation, leading to the concentration (in μg g -1 ) of those four heavy metals of the packed soil increased from 0.51, 46.7, 61.0 and 35.7 to 0.66, 54.2, 70.4 and 38.8, respectively. By contrast, the accumulation of Mn and Pb were quite low. The residual species were the predominant fraction of the six heavy metals (ranged for 59.8-82.4%), followed by oxidisable species. Although the Zn, Cr, Cd, Cu and Mn were efficiently bounded onto the oxide components within the soil, the percentage of the labile metal fractions (water-, acid-exchangeable and reducible metal fractions) exhibited a slight increasing after 2 Y operation. Significantly heavy metals accumulation and slightly decreasing of the proportion of the stable fractions indicated a potentially higher environmental hazard for those six heavy metals after long-term SAT operation (especially for Cu, Zn and Cd). Finally, a linear relationship between the accumulation rate of metal species and the variation of soil organic carbon concentration and water extractable organic carbon was demonstrated. Copyright © 2016 Elsevier Ltd. All rights reserved.

Shields-1, A SmallSat Radiation Shielding Technology Demonstration

NASA Technical Reports Server (NTRS)

Thomsen, D. Laurence, III; Kim, Wousik; Cutler, James W.

2015-01-01

The NASA Langley Research Center Shields CubeSat initiative is to develop a configurable platform that would allow lower cost access to Space for materials durability experiments, and to foster a pathway for both emerging and commercial-off-the-shelf (COTS) radiation shielding technologies to gain spaceflight heritage in a relevant environment. The Shields-1 will be Langleys' first CubeSat platform to carry out this mission. Radiation shielding tests on Shields-1 are planned for the expected severe radiation environment in a geotransfer orbit (GTO), where advertised commercial rideshare opportunities and CubeSat missions exist, such as Exploration Mission 1 (EM-1). To meet this objective, atomic number (Z) graded radiation shields (Zshields) have been developed. The Z-shield properties have been estimated, using the Space Environment Information System (SPENVIS) radiation shielding computational modeling, to have 30% increased shielding effectiveness of electrons, at half the thickness of a corresponding single layer of aluminum. The Shields-1 research payload will be made with the Z-graded radiation shields of varying thicknesses to create dose-depth curves to be compared with baseline materials. Additionally, Shields-1 demonstrates an engineered Z-grade radiation shielding vault protecting the systems' electronic boards. The radiation shielding materials' performances will be characterized using total ionizing dose sensors. Completion of these experiments is expected to raise the technology readiness levels (TRLs) of the tested atomic number (Z) graded materials. The most significant contribution of the Z-shields for the SmallSat community will be that it enables cost effective shielding for small satellite systems, with significant volume constraints, while increasing the operational lifetime of ionizing radiation sensitive components. These results are anticipated to increase the development of CubeSat hardware design for increased mission lifetimes, and enable out of low earth orbit (LEO) missions by using these tested material concepts as shielding for sensitive components and new spaceflight hardware

Revisiting Pneumatic Nail Gun Trigger Recommendations.

PubMed

Albers, James; Lowe, Brian; Lipscomb, Hester; Hudock, Stephen; Dement, John; Evanoff, Bradley; Fullen, Mark; Gillen, Matt; Kaskutas, Vicki; Nolan, James; Patterson, Dennis; Platner, James; Pompeii, Lisa; Schoenfisch, Ashley

2015-03-01

Use of a pneumatic nail gun with a sequential actuation trigger (SAT) significantly diminishes the risk for acute traumatic injury compared to use of a contact actuation trigger (CAT) nail gun. A theoretically-based increased risk of work-related musculoskeletal disorders from use of a SAT nail gun, relative to CAT, appears unlikely and remains unproven. Based on current knowledge, the use of CAT nail guns cannot be justified as a safe alternative to SAT nail guns. This letter provides a perspective of ergonomists and occupational safety researchers recommending the use of the sequential actuation trigger for all nail gun tasks in the construction industry.

Improved Oceanographic Measurements from SAR Altimetry: Results and Scientific Roadmap from the ESA Cryosat Plus for Oceans Project

NASA Astrophysics Data System (ADS)

Benveniste, J.; Cotton, D.; Andersen, O. B.; Boy, F.; Cancet, M.; Dinardo, S.; Gommenginger, C.; Egido, A.; Fernandes, J.; Garcia, P. N.; Lucas, B.; Moreau, T.; Naeije, M.; Scharroo, R.; Stenseng, L.

2014-12-01

The ESA CryoSat mission is the first space mission to carry a radar altimeter that can operate in Synthetic Aperture Radar (SAR) mode. It thus provides the first opportunity to test and evaluate, using real data, the significant potential benefits of SAR altimetry for ocean applications. The objective of the CryoSat Plus for Oceans (CP4O) project is to develop and evaluate new ocean products from CryoSat data and so maximize the scientific return of CryoSat over oceans. The main focus of CP4O has been on the additional measurement capabilities that are offered by the SAR mode of the SIRAL altimeter, with further work in developing improved geophysical corrections. CP4O has developed SAR based ocean products for application in four themes: Open Oceans, Coastal Oceans, Polar Oceans and Sea Floor Topography. The team has developed a number of new processing schemes and compared and evaluated the resultant data products. This work has clearly demonstrated the improved ocean measuring capability offered by SAR mode altimetry and has also added significantly to our understanding of the issues around the processing and interpretation of SAR altimeter echoes. The project finishes in the summer of 2014, so this paper presents an overview of the major results and outlines a proposed roadmap for the further development and exploitation of these results in operational and scientific applications. The results are of course also highly relevant to support the planning for future missions, including Sentinel-3 and Jason-CS. The "CryoSat Plus for Oceans" (CP4O) project has been supported by ESA (Support To Science Element) and CNES.

Evaluation of the KLA-Tencor 2138 for line monitoring applications

NASA Astrophysics Data System (ADS)

Metteer, Brian; Garvin, James F., Jr.; Cataldi, Frank; Ng, Albert; Button, Jon; Newell, Robyn; Rodriguez, Mike D.; Miller, Arlisa

1998-06-01

This report summarizes the results of an evaluation of the KLA-Tencor (KT) 2138 Ultra-Broadband (UBB) optical inspection system performed in the DP1 development facility at Texas Instruments from July 1997 to November 1997. The purpose of this project was to evaluate the effectiveness of the new 2138 UBB system compared to a KT AIT, non-SAT tests on a KT 2135, and SAT recipes on the KT 2132. The 2138 system was designed to provide improved sensitivity and defect detection over the 2135 and other tools. In particular, the UBB illumination source utilized by the 2138 system was expected to provide a significant sensitivity improvement over the 2135 on wafers with color variation as a source of noise. The speeds of the individual pixel tests on the 2138 are the same as those on the 2135. However, it was found that the 2138 0.62 micrometer pixel tests actually found more defects than did the 0.39 micrometer pixel tests on the 2132 on the process levels where this comparison was studied. This type of comparison was not performed between the 2138 and the 2135 since SAT capability was not available on the DP1 2135 during the evaluation. Initially, the primary objective of this project was to measure the UBB system's performance as compared to the 2135 on two Memory levels and three Logic levels. However, since the DP1 2135 system did not possess segmented autothreshold (SAT) capability during this evaluation and the DP1 2132 system did possess SAT capability, the DP1 2132 was added to the evaluation for a 2138 versus 213X SAT direct comparison. Also, the AIT was added to the evaluation plan for a brightfield versus darkfield technology comparison. Finally, three additional Logic levels were added to the evaluation plan, including one Post-CMP level. During this evaluation, the 2138 was proven to be significantly more sensitive than was the 2135, 2132, and the AIT on all process levels compared. Also, very few hardware or software problems were noted during the evaluation.

How CubeSats contribute to Science and Technology in Astronomy and Astrophysics

NASA Astrophysics Data System (ADS)

Cahoy, Kerri Lynn; Douglas, Ewan; Carlton, Ashley; Clark, James; Haughwout, Christian

2017-01-01

CubeSats are nanosatellites, spacecraft typically the size of a shoebox or backpack. CubeSats are made up of one or more 10 cm x 10 cm x 10 cm units weighing 1.33 kg (each cube is called a “U”). CubeSats benefit from relatively easy and inexpensive access to space because they are designed to slide into fully enclosed spring-loaded deployer pods before being attached as an auxiliary payload to a larger vehicle, without adding risk to the vehicle or its primary payload(s). Even though CubeSats have inherent resource and aperture limitations due to their small size, over the past fifteen years, researchers and engineers have miniaturized components and subsystems, greatly increasing the capabilities of CubeSats. We discuss how state of the art CubeSats can address both science objectives and technology objectives in Astronomy and Astrophysics. CubeSats can contribute toward science objectives such as cosmic dawn, galactic evolution, stellar evolution, extrasolar planets and interstellar exploration.CubeSats can contribute to understanding how key technologies for larger missions, like detectors, microelectromechanical systems, and integrated optical elements, can not only survive launch and operational environments (which can often be simulated on the ground), but also meet performance specifications over long periods of time in environments that are harder to simulate properly, such as ionizing radiation, the plasma environment, spacecraft charging, and microgravity. CubeSats can also contribute to both science and technology advancements as multi-element space-based platforms that coordinate distributed measurements and use formation flying and large separation baselines to counter their restricted individual apertures.

Interplanetary CubeSats system for space weather evaluations and technology demonstration

NASA Astrophysics Data System (ADS)

Viscio, Maria Antonietta; Viola, Nicole; Corpino, Sabrina; Stesina, Fabrizio; Fineschi, Silvano; Fumenti, Federico; Circi, Christian

2014-11-01

The paper deals with the mission analysis and conceptual design of an interplanetary 6U CubeSats system to be implemented in the L1 Earth-Sun Lagrangian Point mission for solar observation and in-situ space weather measurements. Interplanetary CubeSats could be an interesting alternative to big missions, to fulfill both scientific and technological tasks in deep space, as proved by the growing interest in this kind of application in the scientific community and most of all at NASA. Such systems allow less costly missions, due to their reduced sizes and volumes, and consequently less demanding launches requirements. The CubeSats mission presented in this paper is aimed at supporting measurements of space weather. The mission envisages the deployment of a 6U CubeSats system in the L1 Earth-Sun Lagrangian Point, where solar observations for in situ measurements of space weather to provide additional warning time to Earth can be carried out. The proposed mission is also intended as a technology validation mission, giving the chance to test advanced technologies, such as telecommunications and solar sails, envisaged as propulsion system. Furthermore, traveling outside the Van Allen belts, the 6U CubeSats system gives the opportunity to further investigate the space radiation environment: radiation dosimeters and advanced materials are envisaged to be implemented, in order to test their response to the harsh space environment, even in view of future implementation on other spacecrafts (e.g. manned spacecrafts). The main issue related to CubeSats is how to fit big science within a small package - namely power, mass, volume, and data limitations. One of the objectives of the work is therefore to identify and size the required subsystems and equipment, needed to accomplish specific mission objectives, and to investigate the most suitable configuration, in order to be compatible with the typical CubeSats (multi units) standards. The work has been developed as collaboration between Politecnico di Torino, Sapienza University of Rome, "Osservatorio Astrofisico di Torino - INAF" (Astrophysical Observatory of Torino) and Deutsches Zentrum für Luft- und Raumfahrt (DLR) in Bremen.

The Small Aircraft Transportation System (SATS): Research Collaborations with the NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Tarry, Scott E.; Bowen, Brent D.; Nickerson, Jocelyn S.

2002-01-01

The aviation industry is an integral part of the world s economy. Travelers have consistently chosen aviation as their mode of transportation as it is reliable, time efficient and safe. The out- dated Hub and Spoke system, coupled with high demand, has led to delays, cancellations and gridlock. NASA is developing innovative solutions to these and other air transportation problems. This research is being conducted through partnerships with federal agencies, industry stakeholders, and academia, specifically the University of Nebraska at Omaha. Each collaborator is pursuing the NASA General Aviation Roadmap through their involvement in the expansion of the Small Aircraft Transportation System (SATS). SATS will utilize technologically advanced small aircraft to transport travelers to and from rural and isolated communities. Additionally, this system will provide a safe alternative to the hub and spoke system, giving more time to more people through high-speed mobility and increased accessibility.

Exploiting Artificial Intelligence for Analysis and Data Selection on-board the Puerto Rico CubeSat

NASA Astrophysics Data System (ADS)

Bergman, J. E. S.; Bruhn, F.; Funk, P.; Isham, B.; Rincón-Charris, A. A.; Capo-Lugo, P.; Åhlén, L.

2015-10-01

CubeSat missions are constrained by the limited resources provided by the platform. Many payload providers have learned to cope with the low mass and power but the poor telemetry allocation remains a bottleneck. In the end, it is the data delivered to ground which determines the value of the mission. However, transmitting more data does not necessarily guarantee high value, since the value also depends on the data quality. By exploiting fast on-board computing and efficient artificial intelligence (AI) algorithms for analysis and data selection one could optimize the usage of the telemetry link and so increase the value of the mission. In a pilot project, we attempt to do this on the Puerto Rico CubeSat, where science objectives include the acquisition of space weather data to aid better understanding of the Sun to Earth connection.

Developing medical students as teachers: an anatomy-based student-as-teacher program with emphasis on core teaching competencies.

PubMed

Andrew Jay, Erie; Starkman, Sidney J; Pawlina, Wojciech; Lachman, Nirusha

2013-01-01

Teaching is an increasingly recognized responsibility of the resident physician. Residents, however, often assume teaching responsibilities without adequate preparation. Consequently, many medical schools have implemented student-as-teacher (SAT) programs that provide near-peer teaching opportunities to senior medical students. Near-peer teaching is widely regarded as an effective teaching modality; however, whether near-peer teaching experiences in medical school prepare students for the teaching demands of residency is less understood. We explored whether the anatomy-based SAT program through the Human Structure didactic block at Mayo Medical School addressed the core teaching competencies of a medical educator and prepared its participants for further teaching roles in their medical careers. A web-based survey was sent to all teaching assistants in the anatomy-based SAT program over the past five years (2007-2011). Survey questions were constructed based on previously published competencies in seven teaching domains--course development, course organization, teaching execution, student coaching, student assessment, teacher evaluation, and scholarship. Results of the survey indicate that participants in the anatomy-based SAT program achieved core competencies of a medical educator and felt prepared for the teaching demands of residency. Copyright © 2013 American Association of Anatomists.

An Imaging System for Satellite Hypervelocity Impact Debris Characterization

NASA Astrophysics Data System (ADS)

Moraguez, M.; Liou, J.; Fitz-Coy, N.; Patankar, K.; Cowardin, H.

This paper discusses the design of an automated imaging system for size characterization of debris produced by the DebriSat hypervelocity impact test. The goal of the DebriSat project is to update satellite breakup models. A representative LEO satellite, DebriSat, was constructed and subjected to a hypervelocity impact test. The impact produced an estimated 85,000 debris fragments. The size distribution of these fragments is required to update the current satellite breakup models. An automated imaging system was developed for the size characterization of the debris fragments. The system uses images taken from various azimuth and elevation angles around the object to produce a 3D representation of the fragment via a space carving algorithm. The system consists of N point-and-shoot cameras attached to a rigid support structure that defines the elevation angle for each camera. The debris fragment is placed on a turntable that is incrementally rotated to desired azimuth angles. The number of images acquired can be varied based on the desired resolution. Appropriate background and lighting is used for ease of object detection. The system calibration and image acquisition process are automated to result in push-button operations. However, for quality assurance reasons, the system is semi-autonomous by design to ensure operator involvement. This paper describes the imaging system setup, calibration procedure, repeatability analysis, and the results of the debris characterization.

An Imaging System for Satellite Hypervelocity Impact Debris Characterization

NASA Technical Reports Server (NTRS)

Moraguez, Matthew; Patankar, Kunal; Fitz-Coy, Norman; Liou, J.-C.; Cowardin, Heather

2015-01-01

This paper discusses the design of an automated imaging system for size characterization of debris produced by the DebriSat hypervelocity impact test. The goal of the DebriSat project is to update satellite breakup models. A representative LEO satellite, DebriSat, was constructed and subjected to a hypervelocity impact test. The impact produced an estimated 85,000 debris fragments. The size distribution of these fragments is required to update the current satellite breakup models. An automated imaging system was developed for the size characterization of the debris fragments. The system uses images taken from various azimuth and elevation angles around the object to produce a 3D representation of the fragment via a space carving algorithm. The system consists of N point-and-shoot cameras attached to a rigid support structure that defines the elevation angle for each camera. The debris fragment is placed on a turntable that is incrementally rotated to desired azimuth angles. The number of images acquired can be varied based on the desired resolution. Appropriate background and lighting is used for ease of object detection. The system calibration and image acquisition process are automated to result in push-button operations. However, for quality assurance reasons, the system is semi-autonomous by design to ensure operator involvement. This paper describes the imaging system setup, calibration procedure, repeatability analysis, and the results of the debris characterization.

Abstracts from the Research and Development Report Series, 1963-81. College Board Report No. 82-1.

ERIC Educational Resources Information Center

Hendel, Patricia K., Ed.

A compilation of 109 abstracts from the "Research and Development Report Series," is presented based on R&D projects conducted during 1963-1981 by Educational Testing Service on behalf of the College Entrance Examination Board. Project titles and authors include the following: "The Effect of Special Preparation on SAT Verbal…

Developing and Planning a Texas Based Homeschool Curriculum

ERIC Educational Resources Information Center

Terry, Bobby K.

2011-01-01

Texas has some of the lowest SAT scores in the nation. They are ranked 36th nationwide in graduation rates and teacher salaries rank at number 33. The public school system in Texas has problems with overcrowding, violence, and poor performance on standardized testing. Currently 300,000 families have opted out of the public school system in order…

Correlates of Persistence and Achievement: Student Support Services at a New England Research University.

ERIC Educational Resources Information Center

Martinez, Marla D.

1999-01-01

A study examined the predictability of student persistence and achievement, based on Scholastic Assessment Test scores, high school rank, mother's education, birth order, and study-skills course grade, in a group of students served by a federal Student Support Services program. Some variables (SAT scores, study-skills course grade) were more…

Lunar and Lagrangian Point L1 L2 CubeSat Communication and Navigation Considerations

NASA Technical Reports Server (NTRS)

Schaire, Scott; Wong, Yen F.; Altunc, Serhat; Bussey, George; Shelton, Marta; Folta, Dave; Gramling, Cheryl; Celeste, Peter; Anderson, Mile; Perrotto, Trish;

Space-Based Optical Communications with CubeSats

NASA Technical Reports Server (NTRS)

Ebert, Monica L.; Nguyen, Anh Ngoc; Frost, Chad

2017-01-01

Optical communication systems use lasers to encode and transmit data with higher speed and density than traditional radio frequency (RF)-based communications. Smaller antennas, lower power requirements, and increased spectrum availability enable optical communications to be integrated into CubeSats more easily than radios, enabling afford-able communications solutions for future NASA missions.

A Proposal to Eliminate the SAT in Berkeley Admissions. Research & Occasional Paper Series: CSHE.4.16

ERIC Educational Resources Information Center

Geiser, Saul

2016-01-01

The SAT is used for two purposes at the University of California. First is "eligibility": Determining whether applicants meet the minimum requirements for admission to the UC system. Second is "admissions selection": At high-demand campuses such as Berkeley, with many more eligible applicants than places available, test scores…

Two Professors Retake the SAT: Is It a Good Test?

ERIC Educational Resources Information Center

Harper, Christopher; Vanderbei, Robert J.

2009-01-01

In this article, two professors retake the college-entrance exam and arrive at very different conclusions about its performance. Even though Christopher Harper has worked as a college professor for 15 years, he decided last winter to take the SAT and ACT examinations that his students needed to enter the institution where he teaches, Temple…

A Three Degrees of Freedom Test-Bed for Nanosatellite and CubeSat Attitude Dynamics, Determination, and Control

DTIC Science & Technology

2009-12-01

Tactical Imaging Nano-sat Yielding Small-Cost Operations and Persistent Earth-coverage UFO UHF Follow On UHF Ultra-High Frequency USCG United...replaced by UHF Follow On ( UFO ) satellites in the 1990s. The UFO satellites are being updated and scheduled for replacement by the Mobile User

Choice of Major: The Changing (Unchanging) Gender Gap.

ERIC Educational Resources Information Center

Turner, Sarah E.; Bowen, William G.

1999-01-01

Data on major choice and Scholastic Aptitude Test (SAT) scores show the following: (1) there is a widening gap between life and math/physical sciences in attractiveness to men and women; (2) SAT scores account for only part of the gap; and (3) gender gaps in major choice are attributable to different preferences, expectations, and gender-specific…

Academic Attributes of College Freshmen that Lead to Success in Actuarial Studies in a Business College

ERIC Educational Resources Information Center

Smith, Richard Manning; Schumacher, Phyllis

2006-01-01

The authors studied beginning undergraduate actuarial concentrators in a business college. They identified four variables (math Scholastic Aptitude Test [SAT] score, verbal SAT score, percentile rank in high school graduating class, and percentage score on a college mathematics placement exam) that were available for entering college students that…

Student Age and the Collegiate Pathway

ERIC Educational Resources Information Center

Hurwitz, Michael; Smith, Jonathan; Howell, Jessica S.

2015-01-01

Using a rich data set of all SAT test takers from the 2004 through 2008 high school graduation cohorts, we investigate the impact of state-specific school age-of-entry laws on students' pathways into and through college. We document that these laws do not impact the probability that a student takes the SAT; however, we find strong evidence that…

Use of the SAT in Advisement and Placement: What the Research Tells Us

ERIC Educational Resources Information Center

Shaw, Emily J.

2009-01-01

Presented at the College Board Western Regional Office (WRO) Forum in San Diego in February 2009. This presentation explores SAT test validity and how it can be used to inform both advisement and placement at the national or institution level. Institutional validity can be measured using the Admitted Class Evaluation Service (ACES) which schools…

The Relationship of Religious Involvement to a Variety of Indicators of Cognitive Ability and Achievement in College Students.

ERIC Educational Resources Information Center

Zern, David S.

1987-01-01

Undergraduates reported anonymously their degree of religiousness, their Scholastic Aptitude Test (SAT) scores, and their grade point averages (GPAs). Found religiousness negatively related to ability, and not related to achievement. The students' capacity to maximize their potential, measured by the standard score difference between GPA and SAT,…

Comparisons of Satellite-Deduced Overlapping Cloud Properties and CALIPSO CloudSat Data

NASA Technical Reports Server (NTRS)

Chang, Fu-Lung; Minnis, Patrick; Lin, Bing; Sun-Mack, Sunny

2010-01-01

Introduction to the overlapped cloud properties derived from polar-orbiting (MODIS) and geostationary (GOES-12, -13, Meteosat-8, -9, etc.) meteorological satellites, which are produced at the NASA Langley Research Center (LaRC) cloud research & development team (NASA lead scientist: Dr. Patrick Minnis). Comparison of the LaRC CERES MODIS Edition-3 overlapped cloud properties to the CALIPSO and the CloudSat active sensing data. High clouds and overlapped clouds occur frequently as deduced by CALIPSO (44 & 25%), CloudSat (25 & 4%), and MODIS (37 & 6%). Large fractions of optically-thin cirrus and overlapped clouds are deduced from CALIPSO, but much smaller fractions are from CloudSat and MODIS. For overlapped clouds, the averaged upper-layer CTHs are about 12.8 (CALIPSO), 10.9 (CloudSat) and 10 km (MODIS), and the averaged lower-layer CTHs are about 3.6 (CALIPSO), 3.2 (CloudSat) and 3.9 km (MODIS). Based on comparisons of upper and lower-layer cloud properties as deduced from the MODIS, CALIPSO and CloudSat data, more enhanced passive satellite methods for retrieving thin cirrus and overlapped cloud properties are needed and are under development.

CSUNSat-1 CubeSat – ELaNa XVII

NASA Image and Video Library

2017-04-04

The primary mission of CSUNSat1 is to space test an innovative low temperature capable energy storage system developed by the Jet Propulsion Laboratory, raising its TRL level to 7 from 4 to 5. The success of this energy storage system will enable future missions, especially those in deep space to do more science while requiring less energy, mass and volume. This CubeSat was designed, built, programmed, and tested by a team of over 70 engineering and computer science students at CSUN.  The primary source of funding for CSUNSat1 comes from NASA’s Smallest Technology Partnership program. Launched by NASA’s CubeSat Launch Initiative on the NET April 18, 2017 ELaNa XVII mission on the seventh Orbital-ATK Cygnus Commercial Resupply Services (OA-7) to the International Space Station and deployed on tbd.

Clinical evaluation of satisfaction in patients rehabilitated with an immediately loaded implant-supported prosthesis: a controlled prospective study.

PubMed

Scala, Rudy; Cucchi, Alessandro; Ghensi, Paolo; Vartolo, Francesco

2012-01-01

The purpose of this controlled prospective study was to compare the satisfaction of patients rehabilitated with an immediately loaded implant-supported prosthesis and patients rehabilitated with a conventional denture in the mandible. Selected mandibular partially or totally edentulous patients were included in this prospective study. Patients' mandibles were completely rehabilitated with immediately loaded implants supporting a screw-retained full-arch prosthesis (test group) or with a conventional denture (control group). The Satisfaction Profile (SAT-P), which investigates a number of psychologic aspects related to the function and esthetics of the stomatognathic apparatus, was administered to each patient 1 month before and 3 months after provisional prosthetic rehabilitation. The questionnaire comprised four different SAT-P items: quality of eating, eating behavior, mood, and self-confidence. A visual analog scale was used to elicit patient responses. SAT-P item scores were analyzed statistically by means of the Student t test and the chi-square test (or the Mann-Whitney nonparametric test), with P < .05 considered significant. Forty-one patients were consecutively treated with 205 immediately loaded implants supporting a screw-retained full-arch prosthesis (test group); 38 patients were consecutively treated with a conventional denture (control group). Statistically significant differences were observed between the test and control groups for all four SAT-P items. The test group reported greater satisfaction for all items versus the control group. In both groups, the differences between pre- and postrehabilitation values were statistically significant. Each patient was satisfied with their treatment outcomes, but patients who received an implant-supported prosthesis were more satisfied than the patients who received a conventional denture. The results suggest that a screw-retained full-arch prosthesis on immediately loaded implants is a predictable means of enhancing patient satisfaction.

TacSat-2: Path finder for a Close Space Support Asset

NASA Astrophysics Data System (ADS)

Bhopale, A.; Finley, C.

2008-08-01

With th e launch of TacSat-2, the Oper ationally Responsive Sp ace (O RS) commun ity had its f irst on- orbit asset and opportunity to prove or disprove the premise that small, in expensiv e, and quickly constructed spacecraf t could perform useful operation al missions when needed and for as long as need ed. All of the components of the comp lex TacSat-2 system had to work together to answer the basic questions, "In a crisis, can a lab-developed spacecraf t and ground architecture competen tly p erform th e mission of systems that cost twen ty times the price and tak e four times as long to develop? Mor eover, can th is system actu ally improve on the responsiveness of Nation al Systems to a certain set of underserv ed Oper ational customers?" When all w as said and done, TacSat-2 was a sp acecraf t that h ad to: 1) Carry th irteen tactical and scientific payloads to orbit, many of which doubled as essen tial, non-redundant subsystems; 2) Launch from an unproven launch base on a last minute "rep lacement" launch vehicle; and 3) Fulfill about 140 on-orbit mission requirements. It had tactical sensors, two unproven communication links, numerous next-gen eration single- string componen ts (e.g., h igh-efficiency propulsion system, thin-film so lar arrays, low-power versatile star camera) , and autonomous softw are to mak e the system more friendly and familiar to Tactical, rather than Spacecraf t Op erators. However, the mission was as mu ch about the implementation as it w as about the components. TacSat-2 was designed for and emp loyed with a different concept of operations ( CONOPS) than tradition al N ational Operational Assets. It w as designed to be th e fir st-ev er Clo se Space Support platform and operated in a manner more analogous to Close Air Support aircraf t than to tr aditional spacecraft. Therefore, th e primary objective of the TacSat-2 mission was to use th e TacSat-2 system to id entify those parts of the spacecr aft, ground system, and CON OPS that mak e it eff ectiv e and su itable for a Tactical Operator emp loying it as a Close Space Support asset. The TacSat-2 story was tru ly a story of survival in the low-budget, high-expectation spacecraft world . The mission su ccesses w ere signif icant and ground- breaking, but they w ere, almost w ithou t exception, compromised successes. Most importan tly, you w ill see an asset th at was unquestionably bo th effective and suitable for military operators, but only worth the investmen t if curren t responsiveness deficiencies dr ive leadership towards a so lution where Close Space Support platforms are a pursued alternativ e. This p aper w ill present the objective positive and negative r esults of the TacSat-2 system' s space/ground components and CONO PS and w ill use these resu lts to project th e co mplexion of an OpSat-X that could best fulfill the role of a Close Sp ace Support p latform directly employed by a front-lin e tactical oper ator to responsively return a product that meets an immediate need.

History of infrared optronics in France

NASA Astrophysics Data System (ADS)

Fouilloy, J. P.; Siriex, Michel B.

1995-09-01

In France, the real start of work on the applications of infrared radiations occurred around 1947 - 1948. During many years, technological research was performed in the field of detectors, optical material, modulation techniques, and a lot of measurements were made in order to acquire a better knowledge of the propagation medium and radiation of IR sources, namely those of jet engines. The birth of industrial infrared activities in France started with the Franco-German missile guidance programs: Milan, HOT, Roland and the French air to air missile seeker programs: R530, MAGIC. At these early stages of IR technologies development, it was a great technical adventure for both the governmental agencies and industry to develop: detector technology with PbS and InSb, detector cooling for 3 - 5 micrometer wavelength range, optical material transparent in the infrared, opto mechanical design, signal processing and related electronic technologies. Etablissement Jean Turck and SAT were the pioneers associated with Aerospatiale, Matra and under contracts from the French Ministry of Defence (DGA). In the 60s, the need arose to enhance night vision capability of equipment in service with the French Army. TRT was chosen by DGA to develop the first thermal imagers: LUTHER 1, 2, and 3 with an increasing number of detectors and image frequency rate. This period was also the era in which the SAT detector made rapid advance. After basic work done in the CNRS and with the support of DGA, SAT became the world leader of MCT photovoltaic detector working in the 8 to 12 micron waveband. From 1979, TRT and SAT were given the responsibility for the joint development and production of the first generation French thermal imaging modular system so-called SMT. Now, THOMSON TTD Optronique takes over the opto-electronics activities of TRT. Laser based systems were also studied for military application using YAG type laser and CO2 laser: Laboratoire de Marcousis, CILAS, THOMSON CSF and SAT have developed during the 70s prototypes for a laser range finder, lidar, laser weapon, and target designator. The constant need to develop increasingly efficient infrared equipment led to a significant increase in the number of detector elements implying the integration of the detector and multiplexer electronic. After tests on several possible technologies at SAT, THOMSON CSF, and LETI, the work performed by these teams in 1980 was concentrated on the development of an MCT type IRCCD detector. The selection of this detector technology for the TRIGAT program led to the creation in 1986 of SOFRADIR with the pooling of the different existing expertise. Much other equipment of the first generation was created during the 80s and is now in production: IRST for naval and airborne applications; IR line scanner for airborne reconnaissance; light thermal imagers for man-portable weapons; infrared seekers for ground to air and air to air missiles; thermal sights for submarine, tank, and missile launch systems; night vision systems for flying helicopter and aircraft; air to ground attack pods for night and day operations.

Effects of Ramadan intermittent fasting on North African children's heart rate and oxy-haemoglobin saturation at rest and during sub-maximal exercise.

PubMed

Fenneni, Mohamed Amine; Latiri, Imed; Aloui, Asma; Rouatbi, Sonia; Chamari, Karim; Saad, Helmi Ben

To examine the effects of Ramadan intermittent fasting (RIF) on the heart rate (HR) and oxyhaemoglobin saturation levels (oxy-sat) of boys at rest and during a six-minute walking test (6MWT). Eighteen boys (age: 11.9 ± 0.8 years, height: 153.00 ± 8.93 cm, body mass: 55.4 ± 18.2 kg), who fasted the entire month of Ramadan in 2012 for the first time in their lives, were included. The experimental protocol comprised four testing phases: two weeks before Ramadan (pre-R), the end of the second week of Ramadan (R-2), the end of the fourth week of Ramadan (R-4), and 10 to 12 days after the end of Ramadan (post-R). During each phase, participants performed the 6MWT at approximately 15:00. HR (expressed as percentage of maximal predicted HR) and oxy-sat (%) were determined at rest and in each minute of the 6MWT. R-4 HR values were lower than those of (1) pre-R (in the second minute), (2) R-2 (in the first and second minutes), and (3) post-R (in the first, second, fourth, fifth and sixth minutes). R-2 oxy-sat values were higher than those of pre-R (in the third minute) and those of post-R (in the fifth minute). Post-R oxy-sat values were lower than those of pre-R and R-4 in the fifth minute. These oxy-sat changes were not clinically significant since the difference was less than five points. In non-athletic children, their first RIF influenced their heart rate data but had a minimal effect on oxy-sat values.

Levels of free fatty acids (FFA) are associated with insulin resistance but do not explain the relationship between adiposity and insulin resistance in Hispanic Americans: the IRAS Family Study.

PubMed

Miller, Melissa R; Pereira, Rocio I; Langefeld, Carl D; Lorenzo, Carlos; Rotter, Jerome I; Chen, Yii-Der Ida; Bergman, Richard N; Wagenknecht, Lynne E; Norris, Jill M; Fingerlin, Tasha E

2012-09-01

We investigated whether free fatty acids (FFA) mediate the association between adiposity and insulin resistance in the Hispanic-American families of the Insulin Resistance Atherosclerosis Family Study. In 815 Hispanic individuals in the Insulin Resistance Atherosclerosis Family Study, we tested for association between the following: 1) levels of adiposity [body mass index (BMI), visceral and sc adipose tissue area (VAT and SAT)] and circulating levels of FFA; 2) levels of circulating FFA and insulin sensitivity (S(I)); and 3) levels of adiposity and S(I), additionally testing to see whether levels of FFA mediated or modified the relationship between adiposity and S(I.) After adjusting for age, sex, clinic site, and admixture, increasing levels of BMI, VAT, and SAT were weakly associated with increasing levels of circulating FFA (BMI: P = 0.024; VAT: P = 2.33 × 10(-3); SAT: P = 0.018; percent variation explained: ∼1.00%). Increasing levels of circulating FFA were associated with decreasing S(I) (P = 8.10 × 10(-11)). Increasing BMI, VAT, and SAT were also associated with decreasing S(I) (BMI: P = 4.98 × 10(-71); VAT: P = 1.48 × 10(-64); SAT: P = 4.21 × 10(-62)), but this relationship was not significantly mediated by FFA. VAT, but not BMI or SAT, interacts with levels of FFA to influence S(I) (P = 0.021). Although levels of circulating FFA are associated both with increasing adiposity and decreasing S(I), they do not appear to mediate the association between levels of adiposity and S(I) in this large cohort of Hispanic-Americans. These results may indicate that FFA contribute to insulin resistance independent of adiposity.

Differential Persistence of Foot-and-Mouth Disease Virus in African Buffalo Is Related to Virus Virulence

PubMed Central

Maree, Francois; de Klerk-Lorist, Lin-Mari; Gubbins, Simon; Zhang, Fuquan; Seago, Julian; Pérez-Martín, Eva; Reid, Liz; Scott, Katherine; van Schalkwyk, Louis; Bengis, Roy; Juleff, Nicholas

2016-01-01

ABSTRACT Foot-and-mouth disease (FMD) virus (FMDV) circulates as multiple serotypes and strains in many regions of endemicity. In particular, the three Southern African Territories (SAT) serotypes are maintained effectively in their wildlife reservoir, the African buffalo, and individuals may harbor multiple SAT serotypes for extended periods in the pharyngeal region. However, the exact site and mechanism for persistence remain unclear. FMD in buffaloes offers a unique opportunity to study FMDV persistence, as transmission from carrier ruminants has convincingly been demonstrated for only this species. Following coinfection of naive African buffaloes with isolates of three SAT serotypes from field buffaloes, palatine tonsil swabs were the sample of choice for recovering infectious FMDV up to 400 days postinfection (dpi). Postmortem examination identified infectious virus for up to 185 dpi and viral genomes for up to 400 dpi in lymphoid tissues of the head and neck, focused mainly in germinal centers. Interestingly, viral persistence in vivo was not homogenous, and the SAT-1 isolate persisted longer than the SAT-2 and SAT-3 isolates. Coinfection and passage of these SAT isolates in goat and buffalo cell lines demonstrated a direct correlation between persistence and cell-killing capacity. These data suggest that FMDV persistence occurs in the germinal centers of lymphoid tissue but that the duration of persistence is related to virus replication and cell-killing capacity. IMPORTANCE Foot-and-mouth disease virus (FMDV) causes a highly contagious acute vesicular disease in domestic livestock and wildlife species. African buffaloes (Syncerus caffer) are the primary carrier hosts of FMDV in African savannah ecosystems, where the disease is endemic. We have shown that the virus persists for up to 400 days in buffaloes and that there is competition between viruses during mixed infections. There was similar competition in cell culture: viruses that killed cells quickly persisted more efficiently in passaged cell cultures. These results may provide a mechanism for the dominance of particular viruses in an ecosystem. PMID:26962214

NASA Operational Simulator for Small Satellites: Tools for Software Based Validation and Verification of Small Satellites

NASA Technical Reports Server (NTRS)

Grubb, Matt

2016-01-01

The NASA Operational Simulator for Small Satellites (NOS3) is a suite of tools to aid in areas such as software development, integration test (IT), mission operations training, verification and validation (VV), and software systems check-out. NOS3 provides a software development environment, a multi-target build system, an operator interface-ground station, dynamics and environment simulations, and software-based hardware models. NOS3 enables the development of flight software (FSW) early in the project life cycle, when access to hardware is typically not available. For small satellites there are extensive lead times on many of the commercial-off-the-shelf (COTS) components as well as limited funding for engineering test units (ETU). Considering the difficulty of providing a hardware test-bed to each developer tester, hardware models are modeled based upon characteristic data or manufacturers data sheets for each individual component. The fidelity of each hardware models is such that FSW executes unaware that physical hardware is not present. This allows binaries to be compiled for both the simulation environment, and the flight computer, without changing the FSW source code. For hardware models that provide data dependent on the environment, such as a GPS receiver or magnetometer, an open-source tool from NASA GSFC (42 Spacecraft Simulation) is used to provide the necessary data. The underlying infrastructure used to transfer messages between FSW and the hardware models can also be used to monitor, intercept, and inject messages, which has proven to be beneficial for VV of larger missions such as James Webb Space Telescope (JWST). As hardware is procured, drivers can be added to the environment to enable hardware-in-the-loop (HWIL) testing. When strict time synchronization is not vital, any number of combinations of hardware components and software-based models can be tested. The open-source operator interface used in NOS3 is COSMOS from Ball Aerospace. For testing, plug-ins are implemented in COSMOS to control the NOS3 simulations, while the command and telemetry tools available in COSMOS are used to communicate with FSW. NOS3 is actively being used for FSW development and component testing of the Simulation-to-Flight 1 (STF-1) CubeSat. As NOS3 matures, hardware models have been added for common CubeSat components such as Novatel GPS receivers, ClydeSpace electrical power systems and batteries, ISISpace antenna systems, etc. In the future, NASA IVV plans to distribute NOS3 to other CubeSat developers and release the suite to the open-source community.

Mothership - Affordable Exploration of Planetary Bodies through Individual Nano-Sats and Swarms

NASA Astrophysics Data System (ADS)

DiCorcia, James D.; Ernst, Sebastian M.; Grace, J. Mike; Gump, David P.; Lewis, John S.; Foulds, Craig F.; Faber, Daniel R.

2015-04-01

One concept to enable broad participation in the scientific exploration of small bodies is the Mothership mission architecture which delivers third-party nano-sats, experiments, and sensors to a near Earth asteroid or comet. Deep Space Industries' Mothership service includes delivery of nano-sats, communication to Earth, and visuals of the asteroid surface and surrounding area. It allows researchers to house their instruments in a low-cost nano-sat platform that does not require the high-performance propulsion or deep space communication capabilities that otherwise would be required for a solo asteroid mission. This enables organizations with relatively low operating budgets to closely examine an asteroid with highly specialized sensors of their own choosing, while the nano-sats can be built or commissioned by a variety of smaller institutions, companies, or agencies. In addition, the Mothership and its deployed nano-sats can offer a platform for instruments which need to be distributed over multiple spacecraft. The Mothership is designed to carry 10 to 12 nano-sats, based upon a variation of the Cubesat standard, with some flexibility on the specific geometry. The Deep Space Nano-Sat reference design is a 14.5 cm cube, which accomodates the same volume as a traditional 3U Cubesat. This design was found to be more favorable for deep space due to its thermal characteristics. The CubeSat standard was originally designed with operations in low Earth orbit in mind. By deliberately breaking the standard, Deep Space Nano-Sats offer better performance with less chance of a critical malfunction in the more hostile deep space environment. The first mission can launch as early as Q4 2017, with subsequent, regular launches through the 2020's.

LEDsats: LEO CubeSats with LEDs for Optical Tracking

NASA Astrophysics Data System (ADS)

Seitzer, P.; Cutler, J.; Piergentili, F.; Santoni, F.; Arena, L.; Cardona, T.; Cowardin, H.; Lee, C.; Sharma, S.

2016-09-01

We describe a project to launch 1U CubeSats equipped with Light Emitting Diodes (LEDs) into Low Earth Orbit (LEO) for optical tracking with ground-based telescopes. Active illumination on the satellites increases tremendously the number of passes where the LEO satellite is visible when the ground-based telescope is in darkness. The restriction that the satellite is in direct Sun is removed, and so tracking can take place all night long rather than just in twilight. The inspiration for this project came from the Japanese CubeSat FITSAT-1 that carried red and green high-powered LED arrays, and was clearly visible from the ground with small telescopes. There are two goals: 1) increase the accuracy and precision of LEO orbits by increasing the number and length of passes that satellite is visible, and 2) minimize the confusion between objects in the case of multiple CubeSats being launched at the same time. Technical issues to be discussed include the power level required for detection by small (20 - 40 cm) ground based telescopes, the optimum flash pattern for astrometry against star fields, and the timing of the flash pattern to millisecond or better accuracy and precision. We propose to deploy two such LEDsats simultaneously from the International Space Station: the first to be built at the University of Michigan, and the second to be built at Sapienza University Rome. One experiment is to see how we can distinguish these two CubeSats shortly after deployment solely from optical tracking, and so the CubeSats will have different flash patterns.

Changes in quantity and spectroscopic properties of water-extractable organic matter during soil aquifer treatment.

PubMed

Xue, S; Zhao, Q L; Wei, L L; Ma, X P; Tie, M

2013-01-01

The aim of this study was to identify qualitative and quantitative changes in the character of water-extractable organic matter (WEOM) in soils as a consequence of soil aquifer treatment (SAT). Soil samples were obtained from a soil-column system with a 2-year operation, and divided into seven layers from top to bottom: CS1 (0-12.5 cm), CS2 (12.5-25 cm), CS3 (25-50 cm), CS4 (50-75 cm), CS5 (75-100 cm), CS6 (100-125 cm) and CS7 (125-150 cm). A sample of the original soil used to pack the columns was also analysed to determine the effects of SAT. Following 2 years of SAT operation, both soil organic carbon and water-extractable organic carbon were shown to accumulate in the top soil layer (0-12.5 cm), and to decrease in soil layers deeper than 12.5 cm. The WEOM in the top soil layer was characterized by low aromaticity index (AI), low emission humification index (HIX) and low fluorescence efficiency index (F(eff)). On the other hand, the WEOM in soil layers deeper than 12.5 cm had increased values of HIX and F(eff), as well as decreased AI values relative to the original soil before SAT. In all soil layers, the percentage of hydrophobic and transphilic fractions decreased, while that of the hydrophilic fraction increased, as a result of SAT. The production of the amide-2 functional groups was observed in the top soil layer. SAT operation also led to the enrichment of hydrocarbon and amide-1 functional groups, as well as the depletion of oxygen-containing functional groups in soil layers deeper than 12.5 cm.

SATS HVO Concept Validation Experiment

NASA Technical Reports Server (NTRS)

Consiglio, Maria; Williams, Daniel; Murdoch, Jennifer; Adams, Catherine

2005-01-01

A human-in-the-loop simulation experiment was conducted at the NASA Langley Research Center s (LaRC) Air Traffic Operations Lab (ATOL) in an effort to comprehensively validate tools and procedures intended to enable the Small Aircraft Transportation System, Higher Volume Operations (SATS HVO) concept of operations. The SATS HVO procedures were developed to increase the rate of operations at non-towered, non-radar airports in near all-weather conditions. A key element of the design is the establishment of a volume of airspace around designated airports where pilots accept responsibility for self-separation. Flights operating at these airports, are given approach sequencing information computed by a ground based automated system. The SATS HVO validation experiment was conducted in the ATOL during the spring of 2004 in order to determine if a pilot can safely and proficiently fly an airplane while performing SATS HVO procedures. Comparative measures of flight path error, perceived workload and situation awareness were obtained for two types of scenarios. Baseline scenarios were representative of today s system utilizing procedure separation, where air traffic control grants one approach or departure clearance at a time. SATS HVO scenarios represented approaches and departure procedures as described in the SATS HVO concept of operations. Results from the experiment indicate that low time pilots were able to fly SATS HVO procedures and maintain self-separation as safely and proficiently as flying today's procedures.

Moderate‐to‐Vigorous Physical Activity With Accelerometry is Associated With Visceral Adipose Tissue in Adults

PubMed Central

Murabito, Joanne M.; Pedley, Alison; Massaro, Joseph M.; Vasan, Ramachandran S.; Esliger, Dale; Blease, Susan J.; Hoffman, Udo; Fox, Caroline S.

2015-01-01

Background We examined the relation between objectively measured physical activity with accelerometry and subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) in a community‐based sample. Methods and Results We evaluated 1249 participants of the Framingham Third Generation and Omni II cohorts (mean age 51.7 years, 47% women) who underwent assessment of moderate‐to‐vigorous physical activity (MVPA) with accelerometry over 5 to 7 days, and multi‐detector computed tomography for measurement of SAT and VAT volume; fat attenuation was estimated by SAT and VAT hounsfield units (HU). In women, higher levels of MVPA were associated with decreased SAT (P<0.0001) and VAT volume (P<0.0001). The average decrement in VAT per 30 minute/day increase in MVPA was −453 cm3 (95% CI −574, −331). The association was attenuated but persisted upon adjustment for BMI (−122 cm3, P=0.002). Higher levels of MVPA were associated with higher SAT HU (all P≤0.01), a marker of fat quality, even after adjustment for SAT volume. Similar findings were observed in men but the magnitude of the association was less. Sedentary time was not associated with SAT or VAT volume or quality in men or women. Conclusions MVPA was associated with less VAT and SAT and better fat quality. PMID:25736442

Automatic Testcase Generation for Flight Software

NASA Technical Reports Server (NTRS)

Bushnell, David Henry; Pasareanu, Corina; Mackey, Ryan M.

2008-01-01

The TacSat3 project is applying Integrated Systems Health Management (ISHM) technologies to an Air Force spacecraft for operational evaluation in space. The experiment will demonstrate the effectiveness and cost of ISHM and vehicle systems management (VSM) technologies through onboard operation for extended periods. We present two approaches to automatic testcase generation for ISHM: 1) A blackbox approach that views the system as a blackbox, and uses a grammar-based specification of the system's inputs to automatically generate *all* inputs that satisfy the specifications (up to prespecified limits); these inputs are then used to exercise the system. 2) A whitebox approach that performs analysis and testcase generation directly on a representation of the internal behaviour of the system under test. The enabling technologies for both these approaches are model checking and symbolic execution, as implemented in the Ames' Java PathFinder (JPF) tool suite. Model checking is an automated technique for software verification. Unlike simulation and testing which check only some of the system executions and therefore may miss errors, model checking exhaustively explores all possible executions. Symbolic execution evaluates programs with symbolic rather than concrete values and represents variable values as symbolic expressions. We are applying the blackbox approach to generating input scripts for the Spacecraft Command Language (SCL) from Interface and Control Systems. SCL is an embedded interpreter for controlling spacecraft systems. TacSat3 will be using SCL as the controller for its ISHM systems. We translated the SCL grammar into a program that outputs scripts conforming to the grammars. Running JPF on this program generates all legal input scripts up to a prespecified size. Script generation can also be targeted to specific parts of the grammar of interest to the developers. These scripts are then fed to the SCL Executive. ICS's in-house coverage tools will be run to measure code coverage. Because the scripts exercise all parts of the grammar, we expect them to provide high code coverage. This blackbox approach is suitable for systems for which we do not have access to the source code. We are applying whitebox test generation to the Spacecraft Health INference Engine (SHINE) that is part of the ISHM system. In TacSat3, SHINE will execute an on-board knowledge base for fault detection and diagnosis. SHINE converts its knowledge base into optimized C code which runs onboard TacSat3. SHINE can translate its rules into an intermediate representation (Java) suitable for analysis with JPF. JPF will analyze SHINE's Java output using symbolic execution, producing testcases that can provide either complete or directed coverage of the code. Automatically generated test suites can provide full code coverage and be quickly regenerated when code changes. Because our tools analyze executable code, they fully cover the delivered code, not just models of the code. This approach also provides a way to generate tests that exercise specific sections of code under specific preconditions. This capability gives us more focused testing of specific sections of code.

Revisiting Pneumatic Nail Gun Trigger Recommendations

PubMed Central

Albers, James; Lipscomb, Hester; Hudock, Stephen; Dement, John; Evanoff, Bradley; Fullen, Mark; Gillen, Matt; Kaskutas, Vicki; Nolan, James; Patterson, Dennis; Platner, James; Pompeii, Lisa; Schoenfisch, Ashley

2015-01-01

Summary Use of a pneumatic nail gun with a sequential actuation trigger (SAT) significantly diminishes the risk for acute traumatic injury compared to use of a contact actuation trigger (CAT) nail gun. A theoretically-based increased risk of work-related musculoskeletal disorders from use of a SAT nail gun, relative to CAT, appears unlikely and remains unproven. Based on current knowledge, the use of CAT nail guns cannot be justified as a safe alternative to SAT nail guns. This letter provides a perspective of ergonomists and occupational safety researchers recommending the use of the sequential actuation trigger for all nail gun tasks in the construction industry. PMID:26366020

ASPECT spectral imaging satellite proposal to AIDA/AIM CubeSat payload

NASA Astrophysics Data System (ADS)

Kohout, Tomas; Näsilä, Antti; Tikka, Tuomas; Penttilä, Antti; Muinonen, Karri; Kestilä, Antti; Granvik, Mikael; Kallio, Esa

2016-04-01

ASPECT (Asteroid Spectral Imaging Mission) is a part of AIDA/AIM project and aims to study the composition of the Didymos binary asteroid and the effects of space weathering and shock metamorphism in order to gain understanding of the formation and evolution of the Solar System. The joint ESA/NASA AIDA (Asteroid Impact & Deflection Assessment) mission to binary asteroid Didymos consists of AIM (Asteroid Impact Mission, ESA) and DART (Double Asteroid Redirection Test, NASA). DART is targeted to impact Didymos secondary component (Didymoon) and serve as a kinetic impactor to demonstrate deflection of potentially hazardous asteroids. AIM will serve as an observational spacecraft to evaluate the effects of the impact and resulting changes in the Didymos dynamic parameters. The AIM mission will also carry two CubeSat miniaturized satellites, released in Didymoon proximity. This arrangement opens up a possibility for secondary scientific experiments. ASPECT is one of the proposed CubeSat payloads. Whereas Didymos is a space-weathered binary asteroid, the DART impactor is expected to produce a crater and excavate fresh material from the secondary component (Didymoon). Spectral comparison of the mature surface to the freshly exposed material will allow to directly deter-mine space weathering effects. It will be also possible to study spectral shock effects within the impact crater. ASPECT will also demonstrate for the first time the joint spacecraft - CubeSat operations in asteroid proximity and miniature spectral imager operation in deep-space environment. Science objectives: 1. Study of the surface composition of the Didymos system. 2. Photometric observations (and modeling) under varying phase angle and distance. 3. Study of space weathering effects on asteroids (comparison of mature / freshly exposed material). 4. Study of shock effects (spectral properties of crater interior). 5. Observations during the DART impact. Engineering objectives: 1. Demonstration of CubeSat semi-autonomous operations in deep space environment. 2. Navigation in the vicinity of a binary asteroid. 3. Demonstration of a satellite survival during impact. 4. Demonstration of joint spacecraft - CubeSat operations. ASPECT is a 3U CubeSat (size of 3 units, Fig. 1) equipped with a spectral imager from 500 nm to 1600 nm (spatial resolution < 2 m, spectral resolution 10 - 30 nm; VIS channel 512 x 512 pixels, NIR channel 256 x 256 pixels), and a non-imaging spectrometer from 1600 - 2500 nm. The design is based on the Aalto-1 CubeSat Spectral Imager heritage. ASPECT will also demonstrate the capabilities of a CubeSat and a miniature spectral imager for the first time in deep-space environment. Acknowledgements: This work is done under Sys-Nova: R&D Studies Competition for Innovation contract with ESA.

Fate of wastewater effluent hER-agonists and hER-antagonists during soil aquifer treatment.

PubMed

Otakuye, Conroy; Quanrud, David M; Ela, Wendell P; Wicke, Daniel; Lansey, Kevin E; Arnold, Robert G

2005-04-01

Estrogen activity was measured in wastewater effluent before and after polishing via soil-aquifer treatment (SAT) using both a (hER-beta) competitive binding assay and a transcriptional activation (yeast estrogen screen, YES) assay. From the competitive binding assay, the equivalent 17alpha-ethinylestradiol (EE2) concentration in secondary effluent was 4.7 nM but decreased to 0.22 nM following SAT. The YES assay indicated that the equivalent EE2 concentration in the same effluent sample was below the method-detection limit (<2.5 x 10(-3) nM) but increased to 0.68 nM in effluent polished via SAT processes. It was hypothesized thattest-dependent differences arose because the competitive binding assay responds positively to both estrogen mimics and anti-estrogens; the YES assay responds to estrogen mimics, but test response is inhibited by anti-estrogens. The hypothesis was supported when organics extracted from wastewater effluent inhibited the YES test response to EE2 (anti-estrogenic effect). A similar extract prepared from SAT-polished effluent augmented the EE2 curve (agonist response). When hydrophobic organics in secondary effluent were fractionated, assay results indicated that several physically distinct anti-estrogens were present in the sample. From this work, it is evident that transcription-activation bioassays alone should not be relied upon to measure estrogenic activity in complex environmental samples because the simultaneous presence of both agonists and antagonist compounds can yield false negatives. Multiple in vitro bioassays, sample fractionation or tests designed to measure anti-estrogenic activity can be used to overcome this problem. It is also clear that there are circumstances under which SAT does not completely remove estrogenic activity during municipal wastewater effluent polishing.

High efficient optical remote sensing images acquisition for nano-satellite-framework

NASA Astrophysics Data System (ADS)

Li, Feng; Xin, Lei; Liu, Yang; Fu, Jie; Liu, Yuhong; Guo, Yi

2017-09-01

It is more difficult and challenging to implement Nano-satellite (NanoSat) based optical Earth observation missions than conventional satellites because of the limitation of volume, weight and power consumption. In general, an image compression unit is a necessary onboard module to save data transmission bandwidth and disk space. The image compression unit can get rid of redundant information of those captured images. In this paper, a new image acquisition framework is proposed for NanoSat based optical Earth observation applications. The entire process of image acquisition and compression unit can be integrated in the photo detector array chip, that is, the output data of the chip is already compressed. That is to say, extra image compression unit is no longer needed; therefore, the power, volume, and weight of the common onboard image compression units consumed can be largely saved. The advantages of the proposed framework are: the image acquisition and image compression are combined into a single step; it can be easily built in CMOS architecture; quick view can be provided without reconstruction in the framework; Given a certain compression ratio, the reconstructed image quality is much better than those CS based methods. The framework holds promise to be widely used in the future.

Enhanced-Resolution Satellite Microwave Brightness Temperature Records for Mapping Boreal-Arctic Landscape Freeze-Thaw Heterogeneity

NASA Astrophysics Data System (ADS)

Kim, Y.; Du, J.; Kimball, J. S.

2017-12-01

The landscape freeze-thaw (FT) status derived from satellite microwave remote sensing is closely linked to vegetation phenology and productivity, surface energy exchange, evapotranspiration, snow/ice melt dynamics, and trace gas fluxes over land areas affected by seasonally frozen temperatures. A long-term global satellite microwave Earth System Data Record of daily landscape freeze-thaw status (FT-ESDR) was developed using similar calibrated 37GHz, vertically-polarized (V-pol) brightness temperatures (Tb) from SMMR, SSM/I, and SSMIS sensors. The FT-ESDR shows mean annual spatial classification accuracies of 90.3 and 84.3 % for PM and AM overpass retrievals relative surface air temperature (SAT) measurement based FT estimates from global weather stations. However, the coarse FT-ESDR gridding (25-km) is insufficient to distinguish finer scale FT heterogeneity. In this study, we tested alternative finer scale FT estimates derived from two enhanced polar-grid (3.125-km and 6-km resolution), 36.5 GHz V-pol Tb records derived from calibrated AMSR-E and AMSR2 sensor observations. The daily FT estimates are derived using a modified seasonal threshold algorithm that classifies daily Tb variations in relation to grid cell-wise FT thresholds calibrated using ERA-Interim reanalysis based SAT, downscaled using a digital terrain map and estimated temperature lapse rates. The resulting polar-grid FT records for a selected study year (2004) show mean annual spatial classification accuracies of 90.1% (84.2%) and 93.1% (85.8%) for respective PM (AM) 3.125km and 6-km Tb retrievals relative to in situ SAT measurement based FT estimates from regional weather stations. Areas with enhanced FT accuracy include water-land boundaries and mountainous terrain. Differences in FT patterns and relative accuracy obtained from the enhanced grid Tb records were attributed to several factors, including different noise contributions from underlying Tb processing and spatial mismatches between Tb retrievals and SAT calibrated FT thresholds.

Advances in Ka-Band Communication System for CubeSats and SmallSats

NASA Technical Reports Server (NTRS)

Kegege, Obadiah; Wong, Yen F.; Altunc, Serhat

2016-01-01

A study was performed that evaluated the feasibility of Ka-band communication system to provide CubeSat/SmallSat high rate science data downlink with ground antennas ranging from the small portable 1.2m/2.4m to apertures 5.4M, 7.3M, 11M, and 18M, for Low Earth Orbit (LEO) to Lunar CubeSat missions. This study included link analysis to determine the data rate requirement, based on the current TRL of Ka-band flight hardware and ground support infrastructure. Recent advances in Ka-band transceivers and antennas, options of portable ground stations, and various coverage distances were included in the analysis. The link/coverage analysis results show that Cubesat/Smallsat missions communication requirements including frequencies and data rates can be met by utilizing Near Earth Network (NEN) Ka-band support with 2 W and high gain (>6 dBi) antennas.

Propulsion for CubeSats

NASA Astrophysics Data System (ADS)

Lemmer, Kristina

2017-05-01

At present, very few CubeSats have flown in space featuring propulsion systems. Of those that have, the literature is scattered, published in a variety of formats (conference proceedings, contractor websites, technical notes, and journal articles), and often not available for public release. This paper seeks to collect the relevant publically releasable information in one location. To date, only two missions have featured propulsion systems as part of the technology demonstration. The IMPACT mission from the Aerospace Corporation launched several electrospray thrusters from Massachusetts Institute of Technology, and BricSAT-P from the United States Naval Academy had four micro-Cathode Arc Thrusters from George Washington University. Other than these two missions, propulsion on CubeSats has been used only for attitude control and reaction wheel desaturation via cold gas propulsion systems. As the desired capability of CubeSats increases, and more complex missions are planned, propulsion is required to accomplish the science and engineering objectives. This survey includes propulsion systems that have been designed specifically for the CubeSat platform and systems that fit within CubeSat constraints but were developed for other platforms. Throughout the survey, discussion of flight heritage and results of the mission are included where publicly released information and data have been made available. Major categories of propulsion systems that are in this survey are solar sails, cold gas propulsion, electric propulsion, and chemical propulsion systems. Only systems that have been tested in a laboratory or with some flight history are included.

Action of an antioxidant complex on the antioxidant power of saliva.

PubMed

Cornelli, U; Belcaro, G; Nardi, G M; Cesarone, M R; Dugall, M; Hosoi, M; Grossi, M G; Ippolito, E; Ledda, A; Ruffini, I

2010-06-01

Based on the results of the soluble antioxidants test (SAT), we have produced a combination of oral antioxidants aimed at increasing the antioxidant power of saliva. Several antioxidants are included in this product (Vit E, beta-carotene, Vit A, Vit C, polyphenols, cathechins, ellagic acid, anthocyanins, coenzyme Q10 and pyridoxine in association with Se, Zn, L-cysteine). The aim of this registry study was to evaluate the efficacy of these antioxidants in saliva, plasma and urines. MF Odontovis, an antioxidant complex, was administered to healthy subjects in the evening for one week with a final administration in the morning. Plasma, urine and saliva showed an increase in antioxidant power following both the evening administration and the final morning administration. The antioxidant action appeared to be present even at night when salival secretion is lower. Plasma SAT levels (SATs) in the morning following evening treatment were increased by 21% in comparison with controls. Morning administration increased levels up to 34% when measured 4 hours after treatment. Comparable increases were observed in saliva (SATs and morning values were +44 %; +58% two hours after morning administration and +28 % after 4 hours). In urine the evening administration caused an increase in antioxidant power (+6%). This study indicated that antioxidant levels can be increased with specific nutritional supplement. The clinical value of an increased antioxidant power in biological fluids, particularly in saliva, may be relevant for future trials of prevention and treatment.

Texts of Our Institutional Lives: SATs for Writing Placement--A Critique and Counterproposal

ERIC Educational Resources Information Center

Isaacs, Emily; Molloy, Sean A.

2010-01-01

Focusing on writing placement at a particular university, the authors analyze the limits of SAT tests as a tool in this process. They then describe the writing program's adoption of a supplementary measure: a faculty committee's review of essays by students who may need to be reassigned to a different writing course. They describe how and why a…

The Impact of the Revamped SAT on Admissions Policies Among Western Land Grant Institutions

ERIC Educational Resources Information Center

Choroszy, Melisa N.; Muehlberg, Jessica

2006-01-01

The newly revamped Scholastic Aptitude Test (SAT) was administered for the first time in March 2005. Administrators, faculty, and staff in colleges and universities throughout the country were asking the same questions as students: "What was this new score of 2400 and what would it mean for them in terms of admissions, scholarships, and…

An Empirical Assessment of Selected Software Purported to Raise SAT Scores Significantly When Utilized With Short-Term CAI on the Microcomputer.

ERIC Educational Resources Information Center

Davis, Wesley D.

This study evaluated Krell's 1981-82 Scholastic Aptitude Test (SAT) preparatory series software purported to raise students' scores substantially after only a short term of computer-assisted instruction (CAI). Forty-eight college-bound juniors from Escambia County (Florida) were assigned to experimental and control groups. A two-phased pre- and…

Dissolved organic matter removal during coal slag additive soil aquifer treatment for secondary effluent recharging: Contribution of aerobic biodegradation.

PubMed

Wei, Liangliang; Li, Siliang; Noguera, Daniel R; Qin, Kena; Jiang, Junqiu; Zhao, Qingliang; Kong, Xiangjuan; Cui, Fuyi

2015-06-01

Recycling wastewater treatment plant (WWTP) effluent at low cost via the soil aquifer treatment (SAT), which has been considered as a renewable approach in regenerating potable and non-potable water, is welcome in arid and semi-arid regions throughout the world. In this study, the effect of a coal slag additive on the bulk removal of the dissolved organic matter (DOM) in WWTP effluent during SAT operation was explored via the matrix configurations of both coal slag layer and natural soil layer. Azide inhibition and XAD-resins fractionation experiments indicated that the appropriate configuration designing of an upper soil layer (25 cm) and a mixture of soil/coal slag underneath would enhance the removal efficiency of adsorption and anaerobic biodegradation to the same level as that of aerobic biodegradation (31.7% vs 32.2%), while it was only 29.4% compared with the aerobic biodegradation during traditional 50 cm soil column operation. The added coal slag would preferentially adsorb the hydrophobic DOM, and those adsorbed organics could be partially biodegraded by the biomass within the SAT systems. Compared with the relatively lower dissolved organic carbon (DOC), ultraviolet light adsorption at 254 nm (UV-254) and trihalomethane formation potential (THMFP) removal rate of the original soil column (42.0%, 32.9%, and 28.0%, respectively), SSL2 and SSL4 columns would enhance the bulk removal efficiency to more than 60%. Moreover, a coal slag additive in the SAT columns could decline the aromatic components (fulvic-like organics and tryptophan-like proteins) significantly. Copyright © 2015 Elsevier Ltd. All rights reserved.

Increasing Small Satellite Reliability- A Public-Private Initiative

NASA Technical Reports Server (NTRS)

Johnson, Michael A.; Beauchamp, Patricia; Schone, Harald; Sheldon, Doug; Fuhrman, Linda; Sullivan, Erica; Fairbanks, Tom; Moe, Miquel; Leitner, Jesse

2017-01-01

At present, CubeSat components and buses are generally not appropriate for missions where significant risk of failure, or the inability to quantify risk or confidence, is acceptable. However, in the future we anticipate that CubeSats will be used for missions requiring reliability of 1-3 years for Earth-observing missions and even longer for Planetary, Heliophysics, and Astrophysics missions. Their growing potential utility is driving an interagency effort to improve and quantify CubeSat reliability, and more generally, small satellite mission risk. The Small Satellite Reliability Initiative (SSRI)—an ongoing activity with broad collaborative participation from civil, DoD, and commercial space systems providers and stakeholders—targets this challenge. The Initiative seeks to define implementable and broadly-accepted approaches to achieve reliability and acceptable risk postures associated with several SmallSat mission risk classes—from “do no harm” missions, to those associated with missions whose failure would result in loss or delay of key national objectives. These approaches will maintain, to the extent practical, cost efficiencies associated with small satellite missions and consider constraints associated with supply chain elements, as appropriate. The SSRI addresses this challenge from two architectural levels—the mission- or system-level, and the component- or subsystem-level. The mission- or system-level scope targets assessment approaches that are efficient and effective, with mitigation strategies that facilitate resiliency to mission or system anomalies while the component- or subsystem-level scope addresses the challenge at lower architectural levels. The initiative does not limit strategies and approaches to proven and traditional methodologies, but is focused on fomenting thought on novel and innovative solutions. This paper discusses the genesis of and drivers for this initiative, how the public-private collaboration is being executed, findings and recommendations derived to date, and next steps towards broadening small satellite mission potential.

Virtual Satellite

NASA Technical Reports Server (NTRS)

Hammrs, Stephan R.

2008-01-01

Virtual Satellite (VirtualSat) is a computer program that creates an environment that facilitates the development, verification, and validation of flight software for a single spacecraft or for multiple spacecraft flying in formation. In this environment, enhanced functionality and autonomy of navigation, guidance, and control systems of a spacecraft are provided by a virtual satellite that is, a computational model that simulates the dynamic behavior of the spacecraft. Within this environment, it is possible to execute any associated software, the development of which could benefit from knowledge of, and possible interaction (typically, exchange of data) with, the virtual satellite. Examples of associated software include programs for simulating spacecraft power and thermal- management systems. This environment is independent of the flight hardware that will eventually host the flight software, making it possible to develop the software simultaneously with, or even before, the hardware is delivered. Optionally, by use of interfaces included in VirtualSat, hardware can be used instead of simulated. The flight software, coded in the C or C++ programming language, is compilable and loadable into VirtualSat without any special modifications. Thus, VirtualSat can serve as a relatively inexpensive software test-bed for development test, integration, and post-launch maintenance of spacecraft flight software.

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

NONE

Training programs at DOE facilities should prepare personnel to safely and efficiently operate and maintain the facilities in accordance with DOE requirements. This guide presents good practices for a systematic approach to on-the-job training (OJT) and OJT programs and should be used in conjunction with DOE Training Program Handbook: A Systematic Approach to Training, and with the DOE Handbook entitled Alternative Systematic Approaches to Training to develop performance-based OJT programs. DOE contractors may also use this guide to modify existing OJT programs that do not meet the systematic approach to training (SAT) objectives.

A physically based algorithm for non-blackbody correction of the cloud top temperature for the convective clouds

NASA Astrophysics Data System (ADS)

Wang, C.; Luo, Z. J.; Chen, X.; Zeng, X.; Tao, W.; Huang, X.

2012-12-01

Cloud top temperature is a key parameter to retrieval in the remote sensing of convective clouds. Passive remote sensing cannot directly measure the temperature at the cloud tops. Here we explore a synergistic way of estimating cloud top temperature by making use of the simultaneous passive and active remote sensing of clouds (in this case, CloudSat and MODIS). Weighting function of the MODIS 11μm band is explicitly calculated by feeding cloud hydrometer profiles from CloudSat retrievals and temperature and humidity profiles based on ECMWF ERA-interim reanalysis into a radiation transfer model. Among 19,699 tropical deep convective clouds observed by the CloudSat in 2008, the averaged effective emission level (EEL, where the weighting function attains its maximum) is at optical depth 0.91 with a standard deviation of 0.33. Furthermore, the vertical gradient of CloudSat radar reflectivity, an indicator of the fuzziness of convective cloud top, is linearly proportional to, d_{CTH-EEL}, the distance between the EEL of 11μm channel and cloud top height (CTH) determined by the CloudSat when d_{CTH-EEL}<0.6km. Beyond 0.6km, the distance has little sensitivity to the vertical gradient of CloudSat radar reflectivity. Based on these findings, we derive a formula between the fuzziness in the cloud top region, which is measurable by CloudSat, and the MODIS 11μm brightness temperature assuming that the difference between effective emission temperature and the 11μm brightness temperature is proportional to the cloud top fuzziness. This formula is verified using the simulated deep convective cloud profiles by the Goddard Cumulus Ensemble model. We further discuss the application of this formula in estimating cloud top buoyancy as well as the error characteristics of the radiative calculation within such deep-convective clouds.

The servicing aid tool: A teleoperated robotics system for space applications

NASA Technical Reports Server (NTRS)

Dorman, Keith W.; Pullen, John L.; Keksz, William O.; Eismann, Paul H.; Kowalski, Keith A.; Karlen, James P.

1994-01-01

The Servicing Aid Tool (SAT) is a teleoperated, force-reflecting manipulation system designed for use on the Space Shuttle. The system will assist Extravehicular Activity (EVA) servicing of spacecraft such as the Hubble Space Telescope. The SAT stands out from other robotics development programs in that special attention was given to provide a low-cost, space-qualified design which can easily and inexpensively be reconfigured and/or enhanced through the addition of existing NASA funded technology as that technology matures. SAT components are spaceflight adaptations of existing ground-based designs from Robotics Research Corporation (RRC), the leading supplier of robotics systems to the NASA and university research community in the United States. Fairchild Space is the prime contractor and provides the control electronics, safety system, system integration, and qualification testing. The manipulator consists of a 6-DOF Slave Arm mounted on a 1-DOF Positioning Link in the shuttle payload bay. The Slave Arm is controlled via a highly similar, 6-DOF, force-reflecting Master Arm from Schilling Development, Inc. This work is being performed under contract to the Goddard Space Flight Center Code, Code 442, Hubble Space Telescope Flight Systems and Servicing Project.

MobileSat (R): A characteristically Australian MSS

NASA Technical Reports Server (NTRS)

Wagg, Michael; Jansen, Michael

1995-01-01

Optus launched its mobile satellite telephone service MobileSat in August 1994. This provided Australia and its neighboring waters with nation-wide mobile telephone coverage and still is the world's only domestic mobile satellite telephone system. This paper provides details of Optus' experience in developing and launching the MobileSat service, including (1) a retrospective of the issues that have waxed and waned in importance during the development and implementation phases, and (2) the strategy for future activities based on the experience gained in the development phase.

A real-time web-based optimal Biomass Site Assessment Tool (BioSAT): Module 1. An economic assessment of mill residues for the southern U.S.

Treesearch

Timothy M. Young; James H. Perdue; Andy Hartsell; Robert C. Abt; Donald Hodges; Timothy G. Rials

2009-01-01

Optimal locations for biomass facilities that use mill residues are identified for 13 southern U.S. states. The Biomass Site Assessment Tool (BioSAT) model is used to identify the top 20 locations for 13 southern U.S. states. The trucking cost model of BioSAT is used with Timber Mart South 2009 price data to estimate the total cost, average cost, and marginal costs for...

Visual attitude propagation for small satellites

NASA Astrophysics Data System (ADS)

Rawashdeh, Samir A.

As electronics become smaller and more capable, it has become possible to conduct meaningful and sophisticated satellite missions in a small form factor. However, the capability of small satellites and the range of possible applications are limited by the capabilities of several technologies, including attitude determination and control systems. This dissertation evaluates the use of image-based visual attitude propagation as a compliment or alternative to other attitude determination technologies that are suitable for miniature satellites. The concept lies in using miniature cameras to track image features across frames and extracting the underlying rotation. The problem of visual attitude propagation as a small satellite attitude determination system is addressed from several aspects: related work, algorithm design, hardware and performance evaluation, possible applications, and on-orbit experimentation. These areas of consideration reflect the organization of this dissertation. A "stellar gyroscope" is developed, which is a visual star-based attitude propagator that uses relative motion of stars in an imager's field of view to infer the attitude changes. The device generates spacecraft relative attitude estimates in three degrees of freedom. Algorithms to perform the star detection, correspondence, and attitude propagation are presented. The Random Sample Consensus (RANSAC) approach is applied to the correspondence problem to successfully pair stars across frames while mitigating falsepositive and false-negative star detections. This approach provides tolerance to the noise levels expected in using miniature optics and no baffling, and the noise caused by radiation dose on orbit. The hardware design and algorithms are validated using test images of the night sky. The application of the stellar gyroscope as part of a CubeSat attitude determination and control system is described. The stellar gyroscope is used to augment a MEMS gyroscope attitude propagation algorithm to minimize drift in the absence of an absolute attitude sensor. The stellar gyroscope is a technology demonstration experiment on KySat-2, a 1-Unit CubeSat being developed in Kentucky that is in line to launch with the NASA ELaNa CubeSat Launch Initiative. It has also been adopted by industry as a sensor for CubeSat Attitude Determination and Control Systems (ADCS). KEYWORDS: Small Satellites, Attitude Determination, Egomotion Estimation, RANSAC, Image Processing.

CubeSat Integration into the Space Situational Awareness Architecture

NASA Astrophysics Data System (ADS)

Morris, K.; Wolfson, M.; Brown, J.

2013-09-01

Lockheed Martin Space Systems Company has recently been involved in developing GEO Space Situational Awareness architectures, which allows insights into how cubesats can augment the current national systems. One hole that was identified in the current architecture is the need for timelier metric track observations to aid in the chain of custody. Obtaining observations of objects at GEO can be supported by CubeSats. These types of small satellites are increasing being built and flown by government agencies like NASA and SMDC. CubeSats are generally mass and power constrained allowing for only small payloads that cannot typically mimic traditional flight capability. CubeSats do not have a high reliability and care must be taken when choosing mission orbits to prevent creating more debris. However, due to the low costs, short development timelines, and available hardware, CubeSats can supply very valuable benefits to these complex missions, affordably. For example, utilizing CubeSats for advanced focal plane demonstrations to support technology insertion into the next generation situational awareness sensors can help to lower risks before the complex sensors are developed. CubeSats can augment the planned ground and space based assets by creating larger constellations with more access to areas of interest. To aid in maintaining custody of objects, a CubeSat constellation at 500 km above GEO would provide increased point of light tracking that can augment the ground SSA assets. Key features of the Cubesat include a small visible camera looking along the GEO belt, a small propulsion system that allows phasing between CubeSats, and an image processor to reduce the data sent to the ground. An elegant communications network will also be used to provide commands to and data from multiple CubeSats. Additional CubeSats can be deployed on GSO launches or through ride shares to GEO, replenishing or adding to the constellation with each launch. Each CubeSat would take images of the GEO belt, process out the stars, and then downlink the data to the ground. This data can then be combined with the existing metric track data to enhance the coverage and timeliness. With the current capability of CubeSats and their payloads, along with the launch constraints, the near term focus is to integrate into existing architectures by reducing technology risks, understanding unique phenomenology, and augment mission collection capability. Understanding the near term benefits of utilizing CubeSats will better inform the SSA mission developers how to integrate CubeSats into the next generation of architectures from the start.

A browser-based 3D Visualization Tool designed for comparing CERES/CALIOP/CloudSAT level-2 data sets.

NASA Astrophysics Data System (ADS)

Chu, C.; Sun-Mack, S.; Chen, Y.; Heckert, E.; Doelling, D. R.

2017-12-01

In Langley NASA, Clouds and the Earth's Radiant Energy System (CERES) and Moderate Resolution Imaging Spectroradiometer (MODIS) are merged with Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and CloudSat Cloud Profiling Radar (CPR). The CERES merged product (C3M) matches up to three CALIPSO footprints with each MODIS pixel along its ground track. It then assigns the nearest CloudSat footprint to each of those MODIS pixels. The cloud properties from MODIS, retrieved using the CERES algorithms, are included in C3M with the matched CALIPSO and CloudSat products along with radiances from 18 MODIS channels. The dataset is used to validate the CERES retrieved MODIS cloud properties and the computed TOA and surface flux difference using MODIS or CALIOP/CloudSAT retrieved clouds. This information is then used to tune the computed fluxes to match the CERES observed TOA flux. A visualization tool will be invaluable to determine the cause of these large cloud and flux differences in order to improve the methodology. This effort is part of larger effort to allow users to order the CERES C3M product sub-setted by time and parameter as well as the previously mentioned visualization capabilities. This presentation will show a new graphical 3D-interface, 3D-CERESVis, that allows users to view both passive remote sensing satellites (MODIS and CERES) and active satellites (CALIPSO and CloudSat), such that the detailed vertical structures of cloud properties from CALIPSO and CloudSat are displayed side by side with horizontally retrieved cloud properties from MODIS and CERES. Similarly, the CERES computed profile fluxes whether using MODIS or CALIPSO and CloudSat clouds can also be compared. 3D-CERESVis is a browser-based visualization tool that makes uses of techniques such as multiple synchronized cursors, COLLADA format data and Cesium.

PhoneSat In-flight Experience Results

NASA Technical Reports Server (NTRS)

Salas, Alberto Guillen; Attai, Watson; Oyadomari, Ken Y.; Priscal, Cedric; Schimmin, Rogan S.; Gazulla, Oriol Tintore; Wolfe, Jasper L.

2014-01-01

Over the last decade, consumer technology has vastly improved its performances, become more affordable and reduced its size. Modern day smartphones offer capabilities that enable us to figure out where we are, which way we are pointing, observe the world around us, and store and transmit this information to wherever we want. These capabilities are remarkably similar to those required for multi-million dollar satellites. The PhoneSat project at NASA Ames Research Center is building a series of CubeSat-size spacecrafts using an off-the-shelf smartphone as its on-board computer with the goal of showing just how simple and cheap space can be. Since the PhoneSat project started, different suborbital and orbital flight activities have proven the viability of this revolutionary approach. In early 2013, the PhoneSat project launched the first triage of PhoneSats into LEO. In the five day orbital life time, the nano-satellites flew the first functioning smartphone-based satellites (using the Nexus One and Nexus S phones), the cheapest satellite (a total parts cost below $3,500) and one of the fastest on-board processors (CPU speed of 1GHz). In this paper, an overview of the PhoneSat project as well as a summary of the in-flight experimental results is presented.

Alternate: MarCO Being Tested in Sunlight

NASA Image and Video Library

2018-03-29

Engineer Joel Steinkraus uses sunlight to test the solar arrays on one of the Mars Cube One (MarCO) spacecraft at NASA's Jet Propulsion Laboratory. The MarCOs will be the first CubeSats -- a kind of modular, mini-satellite -- flown into deep space. They're designed to fly along behind NASA's InSight lander on its cruise to Mars. If they make the journey, they will test a relay of data about InSight's entry, descent and landing back to Earth. Though InSight's mission will not depend on the success of the MarCOs, they will be a test of how CubeSats can be used in deep space. https://photojournal.jpl.nasa.gov/catalog/PIA22318

MarCO Being Tested in Sunlight

NASA Image and Video Library

2018-03-29

Engineer Joel Steinkraus uses sunlight to test the solar arrays on one of the Mars Cube One (MarCO) spacecraft at NASA's Jet Propulsion Laboratory. The MarCOs will be the first CubeSats -- a kind of modular, mini-satellite -- flown into deep space. They're designed to fly along behind NASA's InSight lander on its cruise to Mars. If they make the journey to Mars, they will test a relay of data about InSight's entry, descent and landing back to Earth. Though InSight's mission will not depend on the success of the MarCOs, they will be a test of how CubeSats can be used in deep space. https://photojournal.jpl.nasa.gov/catalog/PIA22317

The Use of Field Programmable Gate Arrays (FPGA) in Small Satellite Communication Systems

NASA Technical Reports Server (NTRS)

Varnavas, Kosta; Sims, William Herbert; Casas, Joseph

2015-01-01

This paper will describe the use of digital Field Programmable Gate Arrays (FPGA) to contribute to advancing the state-of-the-art in software defined radio (SDR) transponder design for the emerging SmallSat and CubeSat industry and to provide advances for NASA as described in the TAO5 Communication and Navigation Roadmap (Ref 4). The use of software defined radios (SDR) has been around for a long time. A typical implementation of the SDR is to use a processor and write software to implement all the functions of filtering, carrier recovery, error correction, framing etc. Even with modern high speed and low power digital signal processors, high speed memories, and efficient coding, the compute intensive nature of digital filters, error correcting and other algorithms is too much for modern processors to get efficient use of the available bandwidth to the ground. By using FPGAs, these compute intensive tasks can be done in parallel, pipelined fashion and more efficiently use every clock cycle to significantly increase throughput while maintaining low power. These methods will implement digital radios with significant data rates in the X and Ka bands. Using these state-of-the-art technologies, unprecedented uplink and downlink capabilities can be achieved in a 1/2 U sized telemetry system. Additionally, modern FPGAs have embedded processing systems, such as ARM cores, integrated inside the FPGA allowing mundane tasks such as parameter commanding to occur easily and flexibly. Potential partners include other NASA centers, industry and the DOD. These assets are associated with small satellite demonstration flights, LEO and deep space applications. MSFC currently has an SDR transponder test-bed using Hardware-in-the-Loop techniques to evaluate and improve SDR technologies.

Autonomous planning and scheduling on the TechSat 21 mission

NASA Technical Reports Server (NTRS)

Sherwood, R.; Chien, S.; Castano, R.; Rabideau, G.

2002-01-01

The Autonomous Sciencecraft Experiment (ASE) will fly onboard the Air Force TechSat 21 constellation of three spacecraft scheduled for launch in 2006. ASE uses onboard continuous planning, robust task and goal-based execution, model-based mode identification and reconfiguration, and onboard machine learning and pattern recognition to radically increase science return by enabling intelligent downlink selection and autonomous retargeting.

Using Observations from GPM and CloudSat to Produce a Climatology of Precipitation over the Ocean

NASA Astrophysics Data System (ADS)

Hayden, L.; Liu, C.

2017-12-01

Satellite based instruments are essential to the observation of precipitation at a global scale, especially over remote oceanic regions. Each instrument has its own strengths and limitations when it comes to accurately determining the rate of precipitation occurring at the surface. By using the complementary strengths of two satellite based instruments, we attempt to produce a more complete climatology of global oceanic precipitation. The Global Precipitation Measurement (GPM) Core Osbervatory's Dual-frequency Precipitation Radar (DPR) is capable of measuring precipitation producing radar reflectivity above 12 dBZ [Hamada and Takayabu 2016]. The CloudSat satellite's Cloud Profiling Radar (CPR) uses higher frequency C band (94 GHz) radiation, and is therefore capable of measuring precipitation occurring at low precipitation rates which are not detected by the GPM DPR. The precipitation estimates derived by the two satellites are combined and the results are examined. CloudSat data from July 2006 to December 2010 are used. GPM data from March 2014 through May 2016 are used. Since the two datasets do not temporally overlap, this study is conducted from a climatological standpoint. The average occurrence for different precipitation rates is calculated for both satellites. To produce the combined dataset, the precipitation from CloudSat are used for the low precipitation rates while CloudSat precipitation amount is greater than that from GPM DPR, until GPM DPR precipitation amount is higher than that from CloudSat, at which precipitation rate data from the GPM are used. By combining the two datasets, we discuss the seasonal and geo-graphical distribution of weak precipitation detected by CloudSat that is beyond the sensitivity of GPM DPR. We also hope to gain a more complete picture of the precipitation that occurs over oceanic regions.

Characterization of Hypervelocity Impact Debris from the DebriSat Tests

NASA Astrophysics Data System (ADS)

Adams, P. M.; Sheaffer, P. M.; Lingley, Z.; Radhakrishnan, G.

The DebriSat program consisted of 3 hypervelocity impact tests conducted in 2 Torr of air with 7 km/s, 600 g aluminum projectiles. In the first test, Pre Preshot, the target consisted of multiple layers of fiberglass, stainless steel and Kevlar fabric. No soft catch foam was used. The subsequent two tests, DebrisLV and DebriSat, were designed to simulate hypervelocity impacts with a launch vehicle upper stage and a modern LEO satellite, respectively. The interior of the chamber was lined with soft catch foam to trap break-up fragments. In all three tests, witness plates were placed near the target to sample impact debris and determine its reflectance, composition and spectral properties. Reflectance measurements are important for calculating the size of orbital hypervelocity impact fragments. The debris from the Pre Preshot test consisted of a two-phase mixture formed from solidified molten silicate and steel droplets. Individual droplets ranged from 100 μm to 10 nm. The reflectance of witness plates dropped from 95% to 20-30% as a result of the debris. Debris collected on witness plates in the DebrisLV and DebriSat tests consisted of μm to nm-sized solidified molten metallic droplets in a matrix of condensed vaporized soft catch. Disordered graphitic carbon was also detected. The reflectance of debris-covered witness plates dropped from 95% to 5%. The dramatic decrease in reflectance for hypervelocity impact debris is attributed to the effect of scattering from μm to nm sized solidified molten metallic droplets and the presence of graphitic carbon, when organics are present. The presence of soft catch in the later tests and the high organic content with graphitic carbon in the debris appear to be responsible for this much lower post-test reflectance. Understanding orbital debris reflectance is critical for estimating size and determining debris detectability.

Passive Polarimetric Microwave Signatures Observed Over Antarctica

USDA-ARS?s Scientific Manuscript database

WindSat satellite-based fully polarimetric passive microwave observations, expressed in the form of the Stokes vector, were analyzed over the Antarctic ice sheet. The vertically and horizontally polarized brightness temperatures (first two Stokes components) from WindSat are shown to be consistent w...

The Optical Profiling of the Atmospheric Limb (OPAL) CubeSat Experiment

NASA Astrophysics Data System (ADS)

Jeppesen, M.; Miller, J.; Cox, W.; Taylor, M. J.; Swenson, C.; Neilsen, T. L.; Fish, C. S.; Scherliess, L.; Christensen, A. B.; Cleave, M.

2015-12-01

The Earth's lower thermosphere is an important interface region between the neutral atmosphere and the "space weather" environment. While the high-latitude region of the thermosphere responds promptly to energy inputs, relatively little is known about the global/regional response to these energy inputs. Global temperatures are predicted to respond within 3-6 hours, but the details of the thermal response of the atmosphere as energy transports away from high-latitude source regions is not well understood. The Optical Profiling of the Atmospheric Limb (OPAL) mission aims to characterize this thermal response through observation of the temperature structure of the lower thermosphere at mid- and low-latitudes. The OPAL instrument is designed to map global thermospheric temperature variability over the critical "thermospheric gap" region (~100-140 km altitude) by spectroscopic analysis of molecular oxygen A-band emission (758 - 768 nm). The OPAL instrument is a grating-based imaging spectrometer with refractive optics and a high-efficiency volume holographic grating (VHG). The scene is sampled by 7 parallel slits that form non-overlapping spectral profiles at the focal plane with resolution of 0.5 nm (spectral), 1.5 km (limb profiling), and 60 km (horizontal sampling). A CCD camera at the instrument focal plane delivers low noise and high sensitivity. The instrument is designed to strongly reject stray light from daylight regions of the earth. The OPAL mission is funded by the National Science Foundation (NSF) CubeSat-based Science Missions for Geospace and Atmospheric Research program. The OPAL instrument, CubeSat bus and mission are being designed, built and executed by a team comprised of students and professors from Utah State University, Dixie State University and the University of Maryland Eastern Shore, with support from professional scientists and engineers from the Space Dynamics Laboratory and Hawk Institute for Space Science.

System Assessment of a High Power 3-U CubeSat

NASA Technical Reports Server (NTRS)

Shaw, Katie

2016-01-01

The Advanced eLectrical Bus (ALBus) CubeSat project is a technology demonstration mission of a 3-UCubeSat with an advanced, digitally controlled electrical power system capability and novel use of Shape Memory Alloy (SMA) technology for reliable deployable solar array mechanisms. The objective of the project is to, through an on orbit demonstration, advance the state of power management and distribution (PMAD) capabilities to enable future missions requiring higher power, flexible and reliable power systems. The goals of the mission include demonstration of: 100 Watt distribution to a target electrical load, efficient battery charging in the orbital environment, flexible power system distribution interfaces, adaptation of power system control on orbit, and reliable deployment of solar arrays and antennas utilizing re-settable SMA mechanisms. The power distribution function of the ALBus PMAD system is unique in the total power to target load capability of 100 W, the flexibility to support centralized or point-to-load regulation and ability to respond to fast transient power requirements. Power will be distributed from batteries at 14.8 V, 6.5 A to provide 100 W of power directly to a load. The deployable solar arrays utilize NASA Glenn Research Center superelastic and activated Nitinol(Nickel-Titanium alloy) Shape Memory Alloy (SMA) technology for hinges and a retention and release mechanism. The deployable solar array hinge design features utilization of the SMA material properties for dual purpose. The hinge uses the shape memory properties of the SMA to provide the spring force to deploy the arrays. The electrical conductivity properties of the SMA also enables the design to provide clean conduits for power transfer from the deployable arrays to the power management system. This eliminates the need for electrical harnesses between the arrays and the PMAD system in the ALBus system design. The uniqueness of the SMA retention and release mechanism design is the ability to reset the mechanism, allowing functional tests of the mechanisms prior to flight with no degradation of performance. The project is currently in preparation at the NASA Glenn Research Center for a launch in late calendar year of 2017. The 100 Watt power distribution and dual purpose, re-settable SMA mechanisms introduced several system level challenges due to the physical constraints in volume, mass and surface area of 3-U CubeSats. Several trade studies and design cycles have been completed to develop a system which supports the project objectives. This paper is a report on the results of the system level trade studies and assessments. The results include assessment of options for thermal control of 100 Watts of power dissipation, data from system analyses and engineering development tests, limitations of the 3-U system and extensibility to larger scale CubeSat missions.

High-throughput analysis of the satellitome revealed enormous diversity of satellite DNAs in the neo-Y chromosome of the cricket Eneoptera surinamensis.

PubMed

Palacios-Gimenez, Octavio Manuel; Dias, Guilherme Borges; de Lima, Leonardo Gomes; Kuhn, Gustavo Campos E Silva; Ramos, Érica; Martins, Cesar; Cabral-de-Mello, Diogo Cavalcanti

2017-07-25

Satellite DNAs (satDNAs) constitute large portion of eukaryote genomes, comprising non-protein-coding sequences tandemly repeated. They are mostly found in heterochromatic regions of chromosomes such as around centromere or near telomeres, in intercalary heterochromatin, and often in non-recombining segments of sex chromosomes. We examined the satellitome in the cricket Eneoptera surinamensis (2n = 9, neo-X 1 X 2 Y, males) to characterize the molecular evolution of its neo-sex chromosomes. To achieve this, we analyzed illumina reads using graph-based clustering and complementary analyses. We found an unusually high number of 45 families of satDNAs, ranging from 4 bp to 517 bp, accounting for about 14% of the genome and showing different modular structures and high diversity of arrays. FISH mapping revealed that satDNAs are located mostly in C-positive pericentromeric regions of the chromosomes. SatDNAs enrichment was also observed in the neo-sex chromosomes in comparison to autosomes. Especially astonishing accumulation of satDNAs loci was found in the highly differentiated neo-Y, including 39 satDNAs over-represented in this chromosome, which is the greatest satDNAs diversity yet reported for sex chromosomes. Our results suggest possible involvement of satDNAs in genome increasing and in molecular differentiation of the neo-sex chromosomes in this species, contributing to the understanding of sex chromosome composition and evolution in Orthoptera.

Characteristics of Minority Students Who Excel on the SAT and in the Classroom. Policy Information Report

ERIC Educational Resources Information Center

Bridgeman, Brent; Wendler, Cathy

2004-01-01

After a few decades of keeping a watchful eye, substantial gaps in the average standardized test scores of White and some minority group students persist. The average group differences on the SAT are among the most visible examples of this pattern, but when we focus only on mean score differences among students, we tend to overlook the relatively…

Predictors of Academic Achievement among Asian American and White Students. College Board Report No. 88-11.

ERIC Educational Resources Information Center

Sue, Stanley; Abe, Jennifer

This study examined the following predictors of academic success for 4,113 Asian American students and 1,000 White students who enrolled as freshmen on any of the eight University of California campuses during fall 1984: (1) high school grade point average (GPA); (2) Scholastic Aptitude Test (SAT)--verbal score; (3) SAT--mathematical score; (4)…

iss038e056422

NASA Image and Video Library

2014-02-25

ISS038-E-056422 (25 Feb. 2014) --- A set of NanoRacks CubeSats is photographed by an Expedition 38 crew member after the deployment by the NanoRacks Launcher attached to the end of the Japanese robotic arm. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing. A blue and white part of Earth provides the backdrop for the scene.

NPS-SCAT; Communications System Design, Test and Integration of NPS’ First CubeSat

DTIC Science & Technology

2010-09-01

18 c. MHX (Primary Transceiver) Wakeup Task ...19 d. Transmit MHX (Primary Transceiver) Task .20 e. Receive MHX (Primary Transceiver...Beacon Antenna Deploy Task......................17  Figure 8.  Collect Data Task...............................19  Figure 9.  MHX Wakeup Task...to provide education while keeping scheduling and cost minimal, and maintaining a standard for building a launchable spacecraft. The CubeSat

Small Aircraft Transportation System Concept and Technologies

NASA Technical Reports Server (NTRS)

Holmes, Bruce J.; Durham, Michael H.; Tarry, Scott E.

2005-01-01

This paper summarizes both the vision and the early public-private collaborative research for the Small Aircraft Transportation System (SATS). The paper outlines an operational definition of SATS, describes how SATS conceptually differs from current air transportation capabilities, introduces four SATS operating capabilities, and explains the relation between the SATS operating capabilities and the potential for expanded air mobility. The SATS technology roadmap encompasses on-demand, widely distributed, point-to-point air mobility, through hired-pilot modes in the nearer-term, and through self-operated user modes in the farther-term. The nearer-term concept is based on aircraft and airspace technologies being developed to make the use of smaller, more widely distributed community reliever and general aviation airports and their runways more useful in more weather conditions, in commercial hired-pilot service modes. The farther-term vision is based on technical concepts that could be developed to simplify or automate many of the operational functions in the aircraft and the airspace for meeting future public transportation needs, in personally operated modes. NASA technology strategies form a roadmap between the nearer-term concept and the farther-term vision. This paper outlines a roadmap for scalable, on-demand, distributed air mobility technologies for vehicle and airspace systems. The audiences for the paper include General Aviation manufacturers, small aircraft transportation service providers, the flight training industry, airport and transportation authorities at the Federal, state and local levels, and organizations involved in planning for future National Airspace System advancements.

KENNEDY SPACE CENTER, FLA. - The SciSat-1 spacecraft is uncrated at Vandenberg Air Force Base, Calif. SciSat-1 weighs approximately 330 pounds and will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The scientific mission of SciSat-1 is to measure and understand the chemical processes that control the distribution of ozone in the Earth’s atmosphere, particularly at high altitudes. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-06-26

KENNEDY SPACE CENTER, FLA. - The SciSat-1 spacecraft is uncrated at Vandenberg Air Force Base, Calif. SciSat-1 weighs approximately 330 pounds and will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The scientific mission of SciSat-1 is to measure and understand the chemical processes that control the distribution of ozone in the Earth’s atmosphere, particularly at high altitudes. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

KENNEDY SPACE CENTER, FLA. - The SciSat-1 spacecraft is revealed after being uncrated at Vandenberg Air Force Base, Calif. SciSat-1 weighs approximately 330 pounds and will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The scientific mission of SciSat-1 is to measure and understand the chemical processes that control the distribution of ozone in the Earth’s atmosphere, particularly at high altitudes. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-06-26

KENNEDY SPACE CENTER, FLA. - The SciSat-1 spacecraft is revealed after being uncrated at Vandenberg Air Force Base, Calif. SciSat-1 weighs approximately 330 pounds and will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The scientific mission of SciSat-1 is to measure and understand the chemical processes that control the distribution of ozone in the Earth’s atmosphere, particularly at high altitudes. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

KENNEDY SPACE CENTER, FLA. - Workers at Vandenberg Air Force Base, Calif., prepare to move the SciSat-1 spacecraft. SciSat-1 weighs approximately 330 pounds and will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The scientific mission of SciSat-1 is to measure and understand the chemical processes that control the distribution of ozone in the Earth’s atmosphere, particularly at high altitudes. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-06-26

KENNEDY SPACE CENTER, FLA. - Workers at Vandenberg Air Force Base, Calif., prepare to move the SciSat-1 spacecraft. SciSat-1 weighs approximately 330 pounds and will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The scientific mission of SciSat-1 is to measure and understand the chemical processes that control the distribution of ozone in the Earth’s atmosphere, particularly at high altitudes. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

The Cloudsat Mission and the EOS Constellation: A New Dimension of Space-Based Observation of Clouds and Precipitation

NASA Technical Reports Server (NTRS)

Stephens, Graeme L.; Vane, Deborah G.; Boain, Ronald; Mace, Gerald; Sassen, Kenneth; Wang, Zhien; Illingworth, Anthony; OConnor, Ewan; Rossow, William; Durden, Stephen L.;

Abdominal Adiposity Distribution Quantified by Ultrasound Imaging and Incident Hypertension in a General Population.

PubMed

Seven, Ekim; Thuesen, Betina H; Linneberg, Allan; Jeppesen, Jørgen L

2016-11-01

Abdominal obesity is a major risk factor for hypertension. However, different distributions of abdominal adipose tissue may affect hypertension risk differently. The main purpose of this study was to explore the association of subcutaneous abdominal adipose tissue (SAT) and visceral adipose tissue (VAT) with incident hypertension in a population-based setting. We hypothesized that VAT, rather than SAT, would be associated with incident hypertension. VAT and SAT were determined by ultrasound imagining in 3363 randomly selected Danes (mean age 49 years, 56% women, mean body mass index 25.8 kg/m 2 ). We constructed multiple logistic regression models to compute standardized odds ratios with 95% confidence intervals per SD increase in SAT and VAT. Of the 2119 normotensive participants at baseline, 1432, with mean SAT of 2.8 cm and mean VAT of 5.7 cm, returned 5 years later for a follow-up examination and among them 203 had developed hypertension. In models including both VAT and SAT, the Framingham Hypertension Risk Score variables (age, sex, smoking status, family history of hypertension, and baseline blood pressure) and glycated hemoglobin, odds ratio (95% confidence interval) for incident hypertension for 1 SD increase in VAT and SAT was 1.27 (1.08-1.50, P=0.004) and 0.97 (0.81-1.15, P=0.70), respectively. Adjusting for body mass index instead of SAT attenuated the association between VAT and incident hypertension, but it was still significant (odds ratio, 1.22 [1.01-1.48, P=0.041] for each SD increase in VAT). In conclusion, ultrasound-determined VAT, but not SAT, was associated with incident hypertension in a random sample of Danish adults. © 2016 American Heart Association, Inc.

Latex agglutination using the periplasmic proteins antigen of Brucella melitensis is a successful, rapid, and specific serodiagnostic test for ovine brucellosis

PubMed Central

Ismael, Alaa Bassuny; Swelum, Ayman Abdel-Aziz; Mostafa, Salama A-H; Alhumiany, Abdel-Rahman A

2016-01-01

Brucellosis, especially caused by Brucella melitensis, is considered the most-widespread zoonosis in the world, particularly in developing countries. This study was planned to develop an accurate test for diagnosis of ovine brucellosis using a specific hot saline extracted soluble Brucella melitensis periplasmic proteins (SBPPs). The efficacy of the latex agglutination test (LAT) using SBPPs compared to the Rose Bengal test (RBT), buffered plate agglutination test (BPAT), serum agglutination test (SAT), and an indirect enzyme-linked immunosorbent assay (i-ELISA) was evaluated in the field diagnosis of ovine brucellosis. The test performance was evaluated by estimating sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), disease prevalence (DP), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using test agreement and bacteriological culture in 1777 samples. The false-positive result was significantly (P ⩽0.05) lower in LAT than RBT, BPAT, SAT, and i-ELISA. With reference to test agreement, the Se, Sp, PPV, and PLR were highest (P ⩽0.05) in LAT 99.33%, 99.88%, 98.68%, and 827.25%, respectively. With reference to bacteriological culture, the LAT and i-ELISA tests showed a significant difference in Se with SAT. However, no significant difference in specificity was detected. The DP was 8.44% in the five tests. In conclusion, LAT using SBPPs of B. melitensis could be a suitable serodiagnostic field test for ovine brucellosis, with high sensitivity and specificity. PMID:27207442

Latex agglutination using the periplasmic proteins antigen of Brucella melitensis is a successful, rapid, and specific serodiagnostic test for ovine brucellosis.

PubMed

Ismael, Alaa Bassuny; Swelum, Ayman Abdel-Aziz; Mostafa, Salama A-H; Alhumiany, Abdel-Rahman A

2016-09-01

Brucellosis, especially caused by Brucella melitensis, is considered the most-widespread zoonosis in the world, particularly in developing countries. This study was planned to develop an accurate test for diagnosis of ovine brucellosis using a specific hot saline extracted soluble Brucella melitensis periplasmic proteins (SBPPs). The efficacy of the latex agglutination test (LAT) using SBPPs compared to the Rose Bengal test (RBT), buffered plate agglutination test (BPAT), serum agglutination test (SAT), and an indirect enzyme-linked immunosorbent assay (i-ELISA) was evaluated in the field diagnosis of ovine brucellosis. The test performance was evaluated by estimating sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), disease prevalence (DP), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using test agreement and bacteriological culture in 1777 samples. The false-positive result was significantly (P ⩽0.05) lower in LAT than RBT, BPAT, SAT, and i-ELISA. With reference to test agreement, the Se, Sp, PPV, and PLR were highest (P ⩽0.05) in LAT 99.33%, 99.88%, 98.68%, and 827.25%, respectively. With reference to bacteriological culture, the LAT and i-ELISA tests showed a significant difference in Se with SAT. However, no significant difference in specificity was detected. The DP was 8.44% in the five tests. In conclusion, LAT using SBPPs of B. melitensis could be a suitable serodiagnostic field test for ovine brucellosis, with high sensitivity and specificity. © The Author(s) 2016.

Severe Accident Test Station Design Document

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

Snead, Mary A.; Yan, Yong; Howell, Michael

The purpose of the ORNL severe accident test station (SATS) is to provide a platform for evaluation of advanced fuels under projected beyond design basis accident (BDBA) conditions. The SATS delivers the capability to map the behavior of advanced fuels concepts under accident scenarios across various temperature and pressure profiles, steam and steam-hydrogen gas mixtures, and thermal shock. The overall facility will include parallel capabilities for examination of fuels and irradiated materials (in-cell) and non-irradiated materials (out-of-cell) at BDBA conditions as well as design basis accident (DBA) or loss of coolant accident (LOCA) conditions. Also, a supporting analytical infrastructure tomore » provide the data-needs for the fuel-modeling components of the Fuel Cycle Research and Development (FCRD) program will be put in place in a parallel manner. This design report contains the information for the first, second and third phases of design and construction of the SATS. The first phase consisted of the design and construction of an out-of-cell BDBA module intended for examination of non-irradiated materials. The second phase of this work was to construct the BDBA in-cell module to test irradiated fuels and materials as well as the module for DBA (i.e. LOCA) testing out-of-cell, The third phase was to build the in-cell DBA module. The details of the design constraints and requirements for the in-cell facility have been closely captured during the deployment of the out-of-cell SATS modules to ensure effective future implementation of the in-cell modules.« less

Star of AOXiang: An innovative 12U CubeSat to demonstrate polarized light navigation and microgravity measurement

NASA Astrophysics Data System (ADS)

Yu, Xiaozhou; Zhou, Jun; Zhu, Peijie; Guo, Jian

2018-06-01

Most of the CubeSats have a volume range from 1U to 3U, which limits their applications due to the difficulty of miniaturizing payloads. To facilitate the needs on a larger but low-cost satellite platform, the AOXiang (AOX) project has been developed by Northwestern Polytechnical University (NPU). The primary objectives of AOX project are four-folds: 1) To demonstrate the world first 12U CubeSat Star of AOXiang and 12U orbit deployer which uses an innovative electromagnetic unlocking technology. 2) To investigate the feasibility of using polarized sunlight for spacecraft attitude determination and navigation, and perform microgravity research using a miniaturized gravimeter. 3) To test a fault tolerant on-board computer using the System On the Programmable Chip (SOPC) technology, and 4) To gain the experience from developing the CubeSat and the subsystems. The CubeSat was launched in June 2016. Now, the mission has achieved all the goals. This paper provides the detail information of the AOX project, with a focus on the introduction of the subsystems of the 12U CubeSat, the orbit deployer and the payloads. The recent in-orbit results of the first NPU are also presented. In addition to the educational objective that has been reached with more than 50 young scholars and students participated in the project.

Deployment Methods for an Origami-Inspired Rigid-Foldable Array

NASA Technical Reports Server (NTRS)

Zirbel, Shannon A.; Trease, Brian P.; Magleby, Spencer P.; Howell, Larry L.

2014-01-01

The purpose of this work is to evaluate several deployment methods for an origami-inspired solar array at two size scales: 25-meter array and CubeSat array. The array enables rigid panel deployment and introduces new concepts for actuating CubeSat deployables. The design for the array was inspired by the origami flasher model (Lang, 1997; Shafer, 2001). Figure 1 shows the array prototyped from Garolite and Kapton film at the CubeSat scale. Prior work demonstrated that rigid panels like solar cells could successfully be folded into the final stowed configuration without requiring the panels to flex (Zirbel, Lang, Thomson, & al., 2013). The design of the array is novel and enables efficient use of space. The array can be wrapped around the central bus of the spacecraft in the case of the large array, or can accommodate storage of a small instrument payload in the case of the CubeSat array. The radial symmetry of this array around the spacecraft is ideally suited for spacecraft that need to spin. This work focuses on several actuation methods for a one-time deployment of the array. The array is launched in its stowed configuration and it will be deployed when it is in space. Concepts for both passive and active actuation were considered.

CubeSat constellations for disaster management in remote areas

NASA Astrophysics Data System (ADS)

Santilli, Giancarlo; Vendittozzi, Cristian; Cappelletti, Chantal; Battistini, Simone; Gessini, Paolo

2018-04-01

In recent years, CubeSats have considerably extended their range of possible applications, from a low cost means to train students and young researchers in space related activities up to possible complementary solutions to larger missions. Increasingly popular, whereas CubeSats are still not a solution for all types of missions, they offer the possibility of performing ambitious scientific experiments. Especially worth considering is the possibility of performing Distributed Space Missions, in which CubeSat systems can be used to increase observation sampling rates and resolutions, as well as to perform tasks that a single satellite is unable to handle. The cost of access to space for traditional Earth Observation (EO) missions is still quite high. Efficient architecture design would allow reducing mission costs by employing CubeSat systems, while maintaining a level of performance that, for some applications, could be close to that provided by larger platforms, and decreasing the time needed to design and deploy a fully functional constellation. For these reasons many countries, including developing nations, agencies and organizations are looking to CubeSat platforms to access space cheaply with, potentially, tens of remote sensing satellites. During disaster management, real-time, fast and continuous information broadcast is a fundamental requirement. In this sense, a constellation of small satellites can considerably decrease the revisit time (defined as the time elapsed between two consecutive observations of the same point on Earth by a satellite) over remote areas, by increasing the number of spacecraft properly distributed in orbit. This allows collecting as much data as possible for the use by Disaster Management Centers. This paper describes the characteristics of a constellation of CubeSats built to enable access over the most remote regions of Brazil, supporting an integrated system for mitigating environmental disasters in an attempt to prevent the catastrophic effects of natural events such as heavy rains that cause flooding. In particular, the paper defines the number of CubeSats and the orbital planes required to minimize the revisit time, depending on the application that is the mission objective. Each CubeSat is equipped with the suitable payloads and possesses the autonomy and pointing capabilities needed to meet the mission requirements. Thanks to the orbital features of the constellation, this service could be exploited by other tropical countries. Coverage of other areas of the Earth might be provided by adjusting the number and in-orbit distribution of the spacecraft.

Goal Structured Notation in a Radiation Hardening Safety Case for COTS-Based Spacecraft

NASA Technical Reports Server (NTRS)

Witulski, Arthur; Austin, Rebekah; Reed, Robert; Karsai, Gabor; Mahadevan, Nag; Sierawski, Brian; Evans, John; LaBel, Ken

2016-01-01

A systematic approach is presented to constructing a radiation assurance case using Goal Structured Notation (GSN) for spacecraft containing COTS parts. The GSN paradigm is applied to an SRAM single-event upset experiment board designed to fly on a CubeSat November 2016. Construction of a radiation assurance case without use of hardened parts or extensive radiation testing is discussed.

Concept, Design, and Prototyping of XSAS: A High Power Extendable Solar Array for CubeSat Applications

NASA Technical Reports Server (NTRS)

Senatore, Patrick; Klesh, Andrew; Zurbuchen, Thomas H.; McKague, Darren; Cutler, James

2010-01-01

CubeSats have proven themselves as a reliable and cost-effective method to perform experiments in space, but they are highly constrained by their specifications and size. One such constraint is the average continuous power, about 5 W, which is available to the typical CubeSat. To improve this constraint, we have developed the eXtendable Solar Array System (XSAS), a deployable solar array prototype in a CubeSat package, which can provide an average 23 W of continuous power. The prototype served as a technology demonstrator for the high risk mechanisms needed to release, deploy, and control the solar array. Aside from this drastic power increase, it is in the integration of each mechanism, their application within the small CubeSat form-factor, and the inherent passive control benefit of the deployed geometry that make XSAS a novel design. In this paper, we discuss the requirements and design process for the XSAS system and mechanical prototype, and provide qualitative and quantitative results from numerical simulations and prototype tests. We also discuss future work, including an upcoming NASA zero-gravity flight campaign, to further improve on XSAS and prepare it for future launch opportunities.

Recently amplified arctic warming has contributed to a continual global warming trend

NASA Astrophysics Data System (ADS)

Huang, Jianbin; Zhang, Xiangdong; Zhang, Qiyi; Lin, Yanluan; Hao, Mingju; Luo, Yong; Zhao, Zongci; Yao, Yao; Chen, Xin; Wang, Lei; Nie, Suping; Yin, Yizhou; Xu, Ying; Zhang, Jiansong

2017-12-01

The existence and magnitude of the recently suggested global warming hiatus, or slowdown, have been strongly debated1-3. Although various physical processes4-8 have been examined to elucidate this phenomenon, the accuracy and completeness of observational data that comprise global average surface air temperature (SAT) datasets is a concern9,10. In particular, these datasets lack either complete geographic coverage or in situ observations over the Arctic, owing to the sparse observational network in this area9. As a consequence, the contribution of Arctic warming to global SAT changes may have been underestimated, leading to an uncertainty in the hiatus debate. Here, we constructed a new Arctic SAT dataset using the most recently updated global SATs2 and a drifting buoys based Arctic SAT dataset11 through employing the `data interpolating empirical orthogonal functions' method12. Our estimate of global SAT rate of increase is around 0.112 °C per decade, instead of 0.05 °C per decade from IPCC AR51, for 1998-2012. Analysis of this dataset shows that the amplified Arctic warming over the past decade has significantly contributed to a continual global warming trend, rather than a hiatus or slowdown.

Flight Technical Error Analysis of the SATS Higher Volume Operations Simulation and Flight Experiments

NASA Technical Reports Server (NTRS)

Williams, Daniel M.; Consiglio, Maria C.; Murdoch, Jennifer L.; Adams, Catherine H.

2005-01-01

This paper provides an analysis of Flight Technical Error (FTE) from recent SATS experiments, called the Higher Volume Operations (HVO) Simulation and Flight experiments, which NASA conducted to determine pilot acceptability of the HVO concept for normal operating conditions. Reported are FTE results from simulation and flight experiment data indicating the SATS HVO concept is viable and acceptable to low-time instrument rated pilots when compared with today s system (baseline). Described is the comparative FTE analysis of lateral, vertical, and airspeed deviations from the baseline and SATS HVO experimental flight procedures. Based on FTE analysis, all evaluation subjects, low-time instrument-rated pilots, flew the HVO procedures safely and proficiently in comparison to today s system. In all cases, the results of the flight experiment validated the results of the simulation experiment and confirm the utility of the simulation platform for comparative Human in the Loop (HITL) studies of SATS HVO and Baseline operations.

CubeSub - A CubeSat Based Submersible Testbed for Space Technology

NASA Technical Reports Server (NTRS)

Slettebo, Christian

2016-01-01

This report is a Master's Thesis in Aerospace Engineering, performed at the NASA Ames Research Center. It describes the development of the CubeSub, a submersible testbed compatible with the CubeSat form factor. The CubeSub will be used to mature technology and operational procedures to be used in space exploration, and possibly also as a tool for exploration of Earthly environments. CubeSats are carried as payloads, either containing technology to be tested or experiments and sensors for scientific use. The CubeSub is designed to be built up by modules, which can be assembled in different configurations to fulfill different needs. Each module is powered individually and intermodular communication is wireless, reducing the need for wiring. The inside of the hull is flooded with ambient water to simplify the interaction between payloads and surrounding environment. The overall shape is similar to that of a conventional AUV, slender and smooth. This is to make for a low drag, reduce the risk of snagging on surrounding objects and make it possible to deploy through an ice sheet via a narrow borehole. Rapid prototyping is utilized to a large extent, with full-scale prototypes being constructed through 3D-printing and with COTS (Commercial Off-The-Shelf) components. Arduino boards are used for control and internal communication. Modules required for basic operation have been designed, manufactured and tested. Each module is described with regards to its function, design and manufacturability. By performing tests in a pool it was found that the basic concept is sound and that future improvements include better controllability, course stability and waterproofing of electrical components. Further development is needed to make the CubeSub usable for its intended purposes. The largest gains are expected to be found by developing the software and improving controllability.

DEVELOPMENT OF HOME CAGE SOCIAL BEHAVIORS IN BALB/cJ vs. C57BL/6J MICE

PubMed Central

Fairless, Andrew H.; Katz, Julia M.; Vijayvargiya, Neha; Dow, Holly C.; Kreibich, Arati Sadalge; Berrettini, Wade H.; Abel, Ted; Brodkin, Edward S.

2012-01-01

BALB/cJ and C57BL/6J inbred mouse strains have been proposed as useful models of low and high levels of sociability (tendency to seek social interaction), respectively, based primarily on behaviors of ~30-day-old mice in the Social Approach Test (SAT). In the SAT, approach and sniffing behaviors of a test mouse toward an unfamiliar stimulus mouse are measured in a novel environment. However, it is unclear whether such results generalize to a familiar environment with a familiar social partner, such as with a littermate in a home cage environment. We hypothesized that C57BL/6J mice would show higher levels of social behaviors than BALB/cJ mice in the home cage environment, particularly at 30 days-of-age. We measured active and passive social behaviors in home cages by pairs of BALB/cJ or C57BL/6J littermates at ages 30, 41, and 69 days. The strains did not differ robustly in their active social behaviors. C57BL/6J mice were more passively social than BALB/cJ mice at 30 days, and C57BL/6J levels of passive social behaviors declined to BALB/cJ levels by 69 days. The differences in passive social behaviors at 30 days-of-age were primarily attributable to differences in huddling. These results indicate that different test conditions (SAT conditions vs. home cage conditions) elicit strain differences in distinct types of behaviors (approach/sniffing vs. huddling behaviors, respectively). Assessment of the more naturalistic social interactions in the familiar home cage environment with a familiar littermate will provide a useful component of a comprehensive assessment of social behaviors in mouse models relevant to autism. PMID:22982070

Distributed Arrays and Signal Processing for the TechSat21 Space-Based Radar

DTIC Science & Technology

2009-04-01

lIlustrating the derivation of minimum aperture size and coherent integration time ............. 25 B 4. Global coordinate system and satellite-based...work of Dr. Robert Mailloux. Dr. Peter Franchi . and Dr. Scott Santarelli. VII Summary The TechSat2l space-based radar concept, suggested by AFRUVS...Linearization for small motions around a reference point in a global circular orbit leads to the Hill equations, derived in 1878, and alternatively named

A twelve-year profile of students' SAT scores, GPAs, and MCAT scores from a small university's premedical program.

PubMed

Montague, J R; Frei, J K

1993-04-01

To determine whether significant correlations existed among quantitative and qualitative predictors of students' academic success and quantitative outcomes of such success over a 12-year period in a small university's premedical program. A database was assembled from information on the 199 graduates who earned BS degrees in biology from Barry University's School of Natural and Health Sciences from 1980 through 1991. The quantitative variables were year of BS degree, total score on the Scholastic Aptitude Test (SAT), various measures of undergraduate grade-point averages (GPAs), and total score on the Medical College Admission Test (MCAT); and the qualitative variables were minority (54% of the students) or majority status and transfer (about one-third of the students) or nontransfer status. The statistical methods were multiple analysis of variance and stepwise multiple regression. Statistically significant positive correlations were found among SAT total scores, final GPAs, biology GPAs versus nonbiology GPAs, and MCAT total scores. These correlations held for transfer versus nontransfer students and for minority versus majority students. Over the 12-year period there were significant fluctuations in mean MCAT scores. The students' SAT scores and GPAs proved to be statistically reliable predictors of MCAT scores, but the minority or majority status and the transfer or nontransfer status of the students were statistically insignificant.

CryoSat Processing Prototype, how to generate LRM like echoes with SAR data and a Comparison to DUACS SLA over high latitudes

NASA Astrophysics Data System (ADS)

Picot, N.; Boy, F.; Desjonqueres, J.

2012-12-01

Like CryoSat, Sentinel3 embarks a doppler altimeter. While there is a long experience of LRM processing, SAR nadir looking data are new and will need in depth validation. Thanks to CryoSat data, the processing of SAR data can be experienced in orbit. The continuity to current altimeter data set (based on LRM acquisitions) has also to be analysed with details. A Cryosat Processing Prototype (C2P) has been developed on CNES side to prepare the CNES SAR ocean retracking study. this prototype allows to process SAR data in order to generate LRM like echoes on ground. Those CryoSat ocean products are routinely processed on CNES side and ingested in the SALP/DUACS system. CryoSat data have proved to be very accurate and very valuable for the ocean user community in the past monthes. For example, it has allowed to largely reduce the impact of the lost of the ESA ENVISAT mission as well as the long non availability of Jason-1 data. This paper will describe the system set up in place early 2012 to feed CryoSat data in the SALP/DUACS products and will present the routine data analysis . C2P CryoSat products will be compared with DUACS SLA estimates and a specific focus will be given over high latitudes knowing that CryoSat is the oinly mission providing sea surface estimates over latitudes above 66 degrees since the lost of the ESA ENVISAT mission.

DNA methylation at a bovine alpha satellite I repeat CpG site during development following fertilization and somatic cell nuclear transfer.

PubMed

Couldrey, Christine; Wells, David N

2013-01-01

Incomplete epigenetic reprogramming is postulated to contribute to the low developmental success following somatic cell nuclear transfer (SCNT). Here, we describe the epigenetic reprogramming of DNA methylation at an alpha satellite I CpG site (αsatI-5) during development of cattle generated either by artificial insemination (AI) or in vitro fertilization (IVF) and SCNT. Quantitative methylation analysis identified that SCNT donor cells were highly methylated at αsatI-5 and resulting SCNT blastocysts showed significantly more methylation than IVF blastocysts. At implantation, no difference in methylation was observed between SCNT and AI in trophoblast tissue at αsatI-5, however, SCNT embryos were significantly hyper-methylated compared to AI controls at this time point. Following implantation, DNA methylation at αsatI-5 decreased in AI but not SCNT placental tissues. In contrast to placenta, the proportion of methylation at αsatI-5 remained high in adrenal, kidney and muscle tissues during development. Differences in the average proportion of methylation were smaller in somatic tissues than placental tissues but, on average, SCNT somatic tissues were hyper-methylated at αsatI-5. Although sperm from all bulls was less methylated than somatic tissues at αsatI-5, on average this site remained hyper-methylated in sperm from cloned bulls compared with control bulls. This developmental time course confirms that epigenetic reprogramming does occur, at least to some extent, following SCNT. However, the elevated methylation levels observed in SCNT blastocysts and cellular derivatives implies that there is either insufficient time or abundance of appropriate reprogramming factors in oocytes to ensure complete reprogramming. Incomplete reprogramming at this CpG site may be a contributing factor to low SCNT success rates, but more likely represents the tip of the iceberg in terms of incompletely reprogramming. Until protocols ensure the epigenetic signature of a differentiated somatic cell is reset to a state resembling totipotency, the efficiency of SCNT is likely to remain low.

DNA Methylation at a Bovine Alpha Satellite I Repeat CpG Site during Development following Fertilization and Somatic Cell Nuclear Transfer

PubMed Central

Couldrey, Christine; Wells, David N.

2013-01-01

Incomplete epigenetic reprogramming is postulated to contribute to the low developmental success following somatic cell nuclear transfer (SCNT). Here, we describe the epigenetic reprogramming of DNA methylation at an alpha satellite I CpG site (αsatI-5) during development of cattle generated either by artificial insemination (AI) or in vitro fertilization (IVF) and SCNT. Quantitative methylation analysis identified that SCNT donor cells were highly methylated at αsatI-5 and resulting SCNT blastocysts showed significantly more methylation than IVF blastocysts. At implantation, no difference in methylation was observed between SCNT and AI in trophoblast tissue at αsatI-5, however, SCNT embryos were significantly hyper-methylated compared to AI controls at this time point. Following implantation, DNA methylation at αsatI-5 decreased in AI but not SCNT placental tissues. In contrast to placenta, the proportion of methylation at αsatI-5 remained high in adrenal, kidney and muscle tissues during development. Differences in the average proportion of methylation were smaller in somatic tissues than placental tissues but, on average, SCNT somatic tissues were hyper-methylated at αsatI-5. Although sperm from all bulls was less methylated than somatic tissues at αsatI-5, on average this site remained hyper-methylated in sperm from cloned bulls compared with control bulls. This developmental time course confirms that epigenetic reprogramming does occur, at least to some extent, following SCNT. However, the elevated methylation levels observed in SCNT blastocysts and cellular derivatives implies that there is either insufficient time or abundance of appropriate reprogramming factors in oocytes to ensure complete reprogramming. Incomplete reprogramming at this CpG site may be a contributing factor to low SCNT success rates, but more likely represents the tip of the iceberg in terms of incompletely reprogramming. Until protocols ensure the epigenetic signature of a differentiated somatic cell is reset to a state resembling totipotency, the efficiency of SCNT is likely to remain low. PMID:23383311

Differential Persistence of Foot-and-Mouth Disease Virus in African Buffalo Is Related to Virus Virulence.

PubMed

Maree, Francois; de Klerk-Lorist, Lin-Mari; Gubbins, Simon; Zhang, Fuquan; Seago, Julian; Pérez-Martín, Eva; Reid, Liz; Scott, Katherine; van Schalkwyk, Louis; Bengis, Roy; Charleston, Bryan; Juleff, Nicholas

2016-05-15

Foot-and-mouth disease (FMD) virus (FMDV) circulates as multiple serotypes and strains in many regions of endemicity. In particular, the three Southern African Territories (SAT) serotypes are maintained effectively in their wildlife reservoir, the African buffalo, and individuals may harbor multiple SAT serotypes for extended periods in the pharyngeal region. However, the exact site and mechanism for persistence remain unclear. FMD in buffaloes offers a unique opportunity to study FMDV persistence, as transmission from carrier ruminants has convincingly been demonstrated for only this species. Following coinfection of naive African buffaloes with isolates of three SAT serotypes from field buffaloes, palatine tonsil swabs were the sample of choice for recovering infectious FMDV up to 400 days postinfection (dpi). Postmortem examination identified infectious virus for up to 185 dpi and viral genomes for up to 400 dpi in lymphoid tissues of the head and neck, focused mainly in germinal centers. Interestingly, viral persistence in vivo was not homogenous, and the SAT-1 isolate persisted longer than the SAT-2 and SAT-3 isolates. Coinfection and passage of these SAT isolates in goat and buffalo cell lines demonstrated a direct correlation between persistence and cell-killing capacity. These data suggest that FMDV persistence occurs in the germinal centers of lymphoid tissue but that the duration of persistence is related to virus replication and cell-killing capacity. Foot-and-mouth disease virus (FMDV) causes a highly contagious acute vesicular disease in domestic livestock and wildlife species. African buffaloes (Syncerus caffer) are the primary carrier hosts of FMDV in African savannah ecosystems, where the disease is endemic. We have shown that the virus persists for up to 400 days in buffaloes and that there is competition between viruses during mixed infections. There was similar competition in cell culture: viruses that killed cells quickly persisted more efficiently in passaged cell cultures. These results may provide a mechanism for the dominance of particular viruses in an ecosystem. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Operations of a Radioisotope-based Propulsion System Enabling CubeSat Exploration of the Outer Planets

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

Dr. Steven Howe; Nathan Jerred; Troy Howe

Exploration to the outer planets is an ongoing endeavor but in the current economical environment, cost reduction is the forefront of all concern. The success of small satellites such as CubeSats launched to Near-Earth Orbit has lead to examine their potential use to achieve cheaper science for deep space applications. However, to achieve lower cost missions; hardware, launch and operations costs must be minimized. Additionally, as we push towards smaller exploration beds with relative limited power sources, allowing for adequate communication back to Earth is imperative. Researchers at the Center for Space Nuclear Research are developing the potential of utilizingmore » an advanced, radioisotope-based system. This system will be capable of providing both the propulsion power needed to reach the destination and the additional requirements needed to maintain communication while at location. Presented here are a basic trajectory analysis, communication link budget and concept of operations of a dual-mode (thermal and electric) radioisotope-based propulsion system, for a proposed mission to Enceladus (Saturnian icy moon) using a 6U CubeSat payload. The radioisotope system being proposed will be the integration of three sub-systems working together to achieve the overall mission. At the core of the system, stored thermal energy from radioisotope decay is transferred to a passing propellant to achieve high thrust – useful for quick orbital maneuvering. An auxiliary closed-loop Brayton cycle can be operated in parallel to the thrusting mode to provide short bursts of high power for high data-rate communications back to Earth. Additionally, a thermal photovoltaic (TPV) energy conversion system will use radiation heat losses from the core. This in turn can provide the electrical energy needed to utilize the efficiency of ion propulsion to achieve quick interplanetary transit times. The intelligent operation to handle all functions of this system under optimized conditions adds to the complexity of the mission architecture.« less

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

NASA Technical Reports Server (NTRS)

Reil, Robin L.

2014-01-01

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

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

NASA Technical Reports Server (NTRS)

Reil, Robin

2014-01-01

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

Using Old and New SAT® Scores for Admission: A Closer Look at Concordant Scores in Predictive Models. Research Report 2016-17

ERIC Educational Resources Information Center

Marini, Jessica P.; Shaw, Emily J.; Young, Linda

2016-01-01

During the transition period between the use of exclusively old SAT® scores and the use of exclusively new SAT scores, college admission offices will be receiving both types of scores from students. Making an admission decision based on new SAT scores can be challenging at first because institutions have methods, procedures, and models based on…

SmallSat Innovations for Planetary Science

NASA Astrophysics Data System (ADS)

Weinberg, Jonathan; Petroy, Shelley; Roark, Shane; Schindhelm, Eric

2017-10-01

As NASA continues to look for ways to fly smaller planetary missions such as SIMPLEX, MoO, and Venus Bridge, it is important that spacecraft and instrument capabilities keep pace to allow these missions to move forward. As spacecraft become smaller, it is necessary to balance size with capability, reliability and payload capacity. Ball Aerospace offers extensive SmallSat capabilities matured over the past decade, utilizing our broad experience developing mission architecture, assembling spacecraft and instruments, and testing advanced enabling technologies. Ball SmallSats inherit their software capabilities from the flight proven Ball Configurable Platform (BCP) line of spacecraft, and may be tailored to meet the unique requirements of Planetary Science missions. We present here recent efforts in pioneering both instrument miniaturization and SmallSat/sensorcraft development through mission design and implementation. Ball has flown several missions with small, but capable spacecraft. We also have demonstrated a variety of enhanced spacecraft/instrument capabilities in the laboratory and in flight to advance autonomy in spaceflight hardware that can enable some small planetary missions.

[Self-directed learning and academic background of 2010 to 2014 cohorts of medical students].

PubMed

Pérez-Villalobos, Cristhian E; Fasce-Henry, Eduardo A; Ortega-Bastidas, Javiera A; Ortiz-Moreira, Liliana E; Bastías-Vega, Nancy; Bustamante-Durán, Carolina E; Ibáñez-Gracia, Pilar; Márquez-Urrizola, Carolina G; Delgado-Rivera, Macarena; Glaría-López, Rocío

2017-07-01

The widespread growth of higher education is increasing the heterogeneity of university students in terms of socioeconomic characteristics, academic story and cultural background. Medical schools are not an exception of this phenomenon. To compare the academic background and self-directed learning behavior of students who entered to a public medial school between 2010 and 2014. A non-probabilistic sample of 527 medical students aged between 17 and 29 years (60% men), was studied. Their academic information was collected from the University data base; they answered the Self-directed learning readiness scale of Fisher. Students from the 2014 cohort had higher high school grades than their counterparts. The scores in mathematics of the Scholarship Aptitude Test (SAT) were higher in the cohorts of 2010 and 2011. Those of the sciences test were superior in the 2013 cohort. The 2014 cohort had the lower general score of self-directed learning behaviors. The lower SAT and self-directed learning scores of the students entering medical school in 2014, indicate the progressive increase in the heterogeneity of Medical students.

Antimicrobial Testing Methods & Procedures: MB-03-07

EPA Pesticide Factsheets

This protocol describes the procedures for the preparation of carriers for the following methods: the AOAC UDM, AOAC Tuberculocidal Activity of Disinfectants Test, AOAC GSPT, the Disinfectant Towelette Test, and the AOAC SAT.

A relative navigation sensor for CubeSats based on LED fiducial markers

NASA Astrophysics Data System (ADS)

Sansone, Francesco; Branz, Francesco; Francesconi, Alessandro

2018-05-01

Small satellite platforms are becoming very appealing both for scientific and commercial applications, thanks to their low cost, short development times and availability of standard components and subsystems. The main disadvantage with such vehicles is the limitation of available resources to perform mission tasks. To overcome this drawback, mission concepts are under study that foresee cooperation between autonomous small satellites to accomplish complex tasks; among these, on-orbit servicing and on-orbit assembly of large structures are of particular interest and the global scientific community is putting a significant effort in the miniaturization of critical technologies that are required for such innovative mission scenarios. In this work, the development and the laboratory testing of an accurate relative navigation package for nanosatellites compliant to the CubeSat standard is presented. The system features a small camera and two sets of LED fiducial markers, and is conceived as a standard package that allows small spacecraft to perform mutual tracking during rendezvous and docking maneuvers. The hardware is based on off-the-shelf components assembled in a compact configuration that is compatible with the CubeSat standard. The image processing and pose estimation software was custom developed. The experimental evaluation of the system allowed to determine both the static and dynamic performances. The system is capable to determine the close range relative position and attitude faster than 10 S/s, with errors always below 10 mm and 2 deg.

Thermal Design, Test and Analysis of PharmaSat, a Small Class D Spacecraft with a Biological Experiment

NASA Technical Reports Server (NTRS)

Diaz-Aguado, Millan F.; VanOutryve, Cassandra; Ghassemiah, Shakib; Beasley, Christopher; Schooley, Aaron

2009-01-01

Small spacecraft have been increasing in popularity because of their low cost, short turnaround and relative efficiency. In the past, small spacecraft have been primarily used for technology demonstrations, but advances in technology have made the miniaturization of space science possible [1,2]. PharmaSat is a low cost, small three cube size spacecraft, with a biological experiment on board, built at NASA (National Aeronautics and Space Administration) Ames Research Center. The thermal design of small spacecraft presents challenges as their smaller surface areas translate into power and thermal constraints. The spacecraft is thermally designed to run colder in the Low Earth Orbit space environment, and heated to reach the temperatures required by the science payload. The limited power supply obtained from the solar panels on small surfaces creates a constraint in the power used to heat the payload to required temperatures. The pressurized payload is isolated with low thermally conductance paths from the large ambient temperature changes. The thermal design consists of different optical properties of section surfaces, Multi Layer Insulation (MLI), low thermal conductance materials, flexible heaters and thermal spreaders. The payload temperature is controlled with temperature sensors and flexible heaters. Finite Element Analysis (FEA) and testing were used to aid the thermal design of the spacecraft. Various tests were conducted to verify the thermal design. An infrared imager was used on the electronic boards to find large heat sources and eliminate any possible temperature runaways. The spacecraft was tested in a thermal vacuum chamber to optimize the thermal and power analysis and qualify the thermal design of the spacecraft for the mission.

OpenSatKit Enables Quick Startup for CubeSat Missions

NASA Technical Reports Server (NTRS)

McComas, David; Melton, Ryan

2017-01-01

The software required to develop, integrate, and operate a spacecraft is substantial regardless of whether its a large or small satellite. Even getting started can be a monumental task. To solve this problem, NASAs Core Flight System (cFS), NASA's 42 spacecraft dynamics simulator, and Ball Aerospaces COSMOS ground system have been integrated together into a kit called OpenSatKit that provides a complete and open source software solution for starting a new satellite mission. Users can have a working system with flight software, dynamics simulation, and a ground command and control system up and running within hours.Every satellite mission requires three primary categories of software to function. The first is Flight Software (FSW) which provides the onboard control of the satellites and its payload(s). NASA's cFS provides a great platform for developing this software. Second, while developing a satellite on earth, it is necessary to simulate the satellites orbit, attitude, and actuators, to ensure that the systems that control these aspects will work correctly in the real environment. NASAs 42 simulator provides these functionalities. Finally, the ground has to be able to communicate with the satellite, monitor its performance and health, and display its data. Additionally, test scripts have to be written to verify the system on the ground. Ball Aerospace's COSMOS command and control system provides this functionality. Once the OpenSatKit is up and running, the next step is to customize the platform and get it running on the end target. Starting from a fully working system makes porting the cFS from Linux to a users platform much easier. An example Raspberry Pi target is included in the kit so users can gain experience working with a low cost hardware target. All users can benefit from OpenSatKit but the greatest impact and benefits will be to SmallSat missions with constrained budgets and small software teams. This paper describes OpenSatKits system design, the steps necessary to run the system to target the Raspberry Pi, and future plans. OpenSatKit is a free fully functional spacecraft software system that we hope will greatly benefit the SmallSat community.

Efficient Authoring of SCORM Courseware Adapted to User Learning Style: The Case of ProPer SAT

NASA Astrophysics Data System (ADS)

Kazanidis, Ioannis; Satratzemi, Maya

Online courses are the most popular way to deliver knowledge for distance learning. New researches attempt to personalize the educational process with the use of the Adaptive Educational Hypermedia Systems. Moreover, due to the significant amount of time, money and effort devoted to creating online courses, developers strive to incorporate standards, such as SCORM, for the reusability, interoperability and durability of the educational content. However, it is a difficult task for teachers without programming knowledge to design and author adaptive courses. This work presents ProPer SAT, an authoring tool implemented for quick and easy SCORM courseware construction which can also be adapted to specific user learning styles.

Tactically Extensible and Modular Communications X-Band TEMCOM-X

NASA Technical Reports Server (NTRS)

Sims, William H.

2015-01-01

This paper will discuss a CubeSat size (3U) telemetry system concept being developed at Marshall Space Flight Center (MSFC) in cooperation with the U.S. Department of the Army and Dynetics Corporation. This telemetry system incorporates efficient, high-bandwidth communications by developing flight-ready, low-cost, Proto-flight software defined radio (SDR) and Electronically Steerable Patch Array (ESPA) antenna subsystems for use on platforms as small as CubeSats and unmanned aircraft systems (UASs). Higher bandwidth capacity will enable high-volume, low error-rate data transfer to and from tactical forces or sensors operating in austere locations (e.g., direct imagery download, unattended ground sensor data exfiltration, interlink communications).

Evaluation of NCAR CAM5 Simulated Marine Boundary Layer Cloud Properties Using a Combination of Satellite and Surface Observations

NASA Astrophysics Data System (ADS)

Zhang, Z.; Song, H.; Wang, M.; Ghan, S. J.; Dong, X.

2016-12-01

he main objective of this study is to systematically evaluate the MBL cloud properties simulated in CAM5 family models using a combination of satellite-based CloudSat/MODIS observations and ground-based observations from the ARM Azores site, with a special focus on MBL cloud microphysics and warm rain process. First, we will present a global evaluation based on satellite observations and retrievals. We will compare global cloud properties (e.g., cloud fraction, cloud vertical structure, cloud CER, COT, and LWP, as well as drizzle frequency and intensity diagnosed using the CAM5-COSP instrumental simulators) simulated in the CAM5 models with the collocated CloudSat and MODIS observations. We will also present some preliminary results from a regional evaluation based mainly on ground observations from ARM Azores site. We will compare MBL cloud properties simulated in CAM5 models over the ARM Azores site with collocated satellite (MODIS and CloudSat) and ground-based observations from the ARM site.

A Multi-Variable Approach to Diagnosing the Monthly Covariability of the Amazonian Radiative and Convective Diurnal Cycles

NASA Astrophysics Data System (ADS)

Dodson, J. B.; Taylor, P. C.

2016-12-01

The diurnal cycle of convection (CDC) greatly influences the water, radiative, and energy budgets in convectively active regions. For example, previous research of the Amazonian CDC has identified significant monthly covariability between the satellite-observed radiative and precipitation diurnal and multiple reanalysis-derived atmospheric state variables (ASVs) representing convective instability. However, disagreements between retrospective analysis products (reanalyses) over monthly ASV anomalies create significant uncertainty in the resulting covariability. Satellite observations of convective clouds can be used to characterize monthly anomalies in convective activity. CloudSat observes multiple properties of both deep convective cores and the associated anvils, and so is useful as an alternative to the use of reanalyses. CloudSat cannot observe the full diurnal cycle, but it can detect differences between daytime and nighttime convection. Initial efforts to use CloudSat data to characterize convective activity showed that the results are highly dependent on the choice of variable used to characterize the cloud. This is caused by a series of inverse relationships between convective frequency, cloud top height, radar reflectivity vertical profile, and other variables. A single, multi-variable index for convective activity based on CloudSat data may be useful to clarify the results. Principal component analysis (PCA) provides a method to create a multivariable index, where the first principal component (PC1) corresponds with convective instability. The time series of PC1 can then be used as a proxy for monthly variability in convective activity. The primary challenge presented involves determining the utility of PCA for creating a robust index for convective activity that accounts for the complex relationships of multiple convective cloud variables, and yields information about the interactions between convection, the convective environment, and radiation beyond the previous single-variable approaches. The choice of variables used to calculate PC1 may influence any results based on PC1, so it is necessary to test the sensitivity of the results to different variable combinations.

Design and Functional Validation of a Mechanism for Dual-Spinning CubeSats

NASA Technical Reports Server (NTRS)

Peters, Eric; Dave, Pratik; Kingsbury, Ryan; Marinan, Anne; Wise, Evan; Pong, Chris; Prinkey, Meghan; Cahoy, Kerri; Miller, David W.; Sklair, Devon

2014-01-01

The mission of the Micro-sized Microwave Atmospheric Satellite (MicroMAS) is to collect useful atmospheric images using a miniature passive microwave radiometer payload hosted on a low-cost CubeSat platform. In order to collect this data, the microwave radiometer payload must rotate to scan the ground-track perpendicular to the satellite's direction of travel. A custom motor assembly was developed to facilitate the rotation of the payload while allowing the spacecraft bus to remained fixed in the local-vertical, local-horizontal (LVLH) frame for increased pointing accuracy. This paper describes the mechanism used to enable this dual-spinning operation for CubeSats, and the lessons learned during the design, fabrication, integration, and testing phases of the mechanism's development lifecycle.

Paving the Way for Small Satellite Access to Orbit: Cyclops' Deployment of SpinSat, the Largest Satellite Ever Deployed from the International Space Station

NASA Technical Reports Server (NTRS)

Hershey, Matthew P.; Newswander, Daniel R.; Smith, James P.; Lamb, Craig R.; Ballard, Perry G.

2015-01-01

The Space Station Integrated Kinetic Launcher for Orbital Payload Systems (SSIKLOPS), known as "Cyclops" to the International Space Station (ISS) community, successfully deployed the largest satellite ever (SpinSat) from the ISS on November 28, 2014. Cyclops, a collaboration between the NASA ISS Program, NASA Johnson Space Center Engineering, and Department of Defense Space Test Program (DoD STP) communities, is a dedicated 10-100 kg class ISS small satellite deployment system. This paper will showcase the successful deployment of SpinSat from the ISS. It will also outline the concept of operations, interfaces, requirements, and processes for satellites to utilize the Cyclops satellite deployment system.

Diffusion Monte Carlo approach versus adiabatic computation for local Hamiltonians

NASA Astrophysics Data System (ADS)

Bringewatt, Jacob; Dorland, William; Jordan, Stephen P.; Mink, Alan

2018-02-01

Most research regarding quantum adiabatic optimization has focused on stoquastic Hamiltonians, whose ground states can be expressed with only real non-negative amplitudes and thus for whom destructive interference is not manifest. This raises the question of whether classical Monte Carlo algorithms can efficiently simulate quantum adiabatic optimization with stoquastic Hamiltonians. Recent results have given counterexamples in which path-integral and diffusion Monte Carlo fail to do so. However, most adiabatic optimization algorithms, such as for solving MAX-k -SAT problems, use k -local Hamiltonians, whereas our previous counterexample for diffusion Monte Carlo involved n -body interactions. Here we present a 6-local counterexample which demonstrates that even for these local Hamiltonians there are cases where diffusion Monte Carlo cannot efficiently simulate quantum adiabatic optimization. Furthermore, we perform empirical testing of diffusion Monte Carlo on a standard well-studied class of permutation-symmetric tunneling problems and similarly find large advantages for quantum optimization over diffusion Monte Carlo.

Sea cucumbers with an anti-inflammatory effect on endothelial cells and subcutaneous but not on epicardial adipose tissue.

PubMed

Mena-Bueno, Sara; Atanasova, Miroslava; Fernández-Trasancos, Ángel; Paradela-Dobarro, Beatriz; Bravo, Susana B; Álvarez, Ezequiel; Fernández, Ángel L; Carrera, Iván; González-Juanatey, José R; Eiras, Sonia

2016-02-01

epicardial adipose tissue (EAT) from patients with coronary artery disease (CAD) contains higher levels of inflammatory proteins and lower adiponectin levels than subcutaneous adipose tissue (SAT), enhancing the progression of atherosclerosis. Since products from sea cucumber have anti-inflammatory properties, we investigated its effect on EAT, SAT and endothelial cells. stromal cells or explants from EAT and SAT were obtained from patients with cardiovascular disease. Extracts were obtained after hydrolysis by food-grade enzymes at different times. Proteins were identified by LC-MALDI mass spectrometry. Adipogenesis and adiponectin induction were determined on stromal cells in the presence/absence of extracts. The bioavailability of the extracts was tested on a Caco-2 cell culture model in vitro. The bioavailable fraction was probed on endothelial cells and EAT or SAT explants. Vascular cell adhesion protein (VCAM-1), intercellular adhesion molecule (ICAM-1), IL-6 and adiponectin were determined by real time polymerase chain reaction (RT-PCR). our results showed that H. forskali and P. tremulus extracts contained compounds with anti-oxidant and anti-inflammatory properties. The bioavailable fraction of P. tremulus reduced VCAM-1 (p < 0.01) and IL-6 (p < 0.05) expression levels in endothelial cells while bioavailable compounds from H. forskali decreased ICAM-1 expression in SAT (p < 0.05). No effect was observed on EAT. these results suggest that sea cucumber extracts might be used for the prevention of endothelial cells and SAT inflammation.

CryoSat SAR/SARin Level1b products: assessment of BaselineC and improvements towards BaselineD

NASA Astrophysics Data System (ADS)

Scagliola, Michele; Fornari, Marco; Bouffard, Jerome; Parrinello, Tommaso

2017-04-01

CryoSat was launched on the 8th April 2010 and is the first European ice mission dedicated to the monitoring of precise changes in the thickness of polar ice sheets and floating sea ice. Cryosat carries an innovative radar altimeter called the Synthetic Aperture Interferometric Altimeter (SIRAL), that transmits pulses at a high pulse repetition frequency thus making the received echoes phase coherent and suitable for azimuth processing. This allows to reach a significantly improved along track resolution with respect to traditional pulse-width limited altimeters. CryoSat is the first altimetry mission operating in SAR mode and continuous improvements in the Level1 Instrument Processing Facility (IPF1) are being identified, tested and validated in order to improve the quality of the Level1b products. The current IPF, Baseline C, was released in operation in April 2015 and the second CryoSat reprocessing campaign was jointly initiated, taking benefit of the upgrade implemented in the IPF1 processing chain but also of some specific configurations for the calibration corrections. In particular, the CryoSat Level1b BaselineC products generated in the framework of the second reprocessing campaign include refined information for what concerns the mispointing angles and the calibration corrections. This poster will thus detail thus the evolutions that are currently planned for the CryoSat BaselineD SAR/SARin Level1b products and the corresponding quality improvements that are expected.

Do later wake times and increased sleep duration of 12th graders result in more studying, higher grades, and improved SAT/ACT test scores?

PubMed

Cole, James S

2016-09-01

The aim of this study was to investigate the relationship between sleep duration, wake time, and hours studying on high school grades and performance on the Scholastic Aptitude Test (SAT)/ American College Testing (ACT) college entrance exams. Data were collected from 13,071 recently graduated high school seniors who were entering college in the fall of 2014. A column proportions z test with a Bonferroni adjustment was used to analyze proportional differences. Analysis of covariance (ANCOVA) was used to examine mean group differences. Students who woke up prior to 6 a.m. and got less than 8 h of sleep (27 %) were significantly more likely to report studying 11 or more hours per week (30 %), almost double the rate compared to students who got more than 8 h of sleep and woke up the latest (16 %). Post hoc results revealed students who woke up at 7 a.m. or later reported significantly higher high school grades than all other groups (p < 0.001), with the exception of those students who woke up between 6:01 a.m. and 7:00 a.m. and got eight or more hours of sleep. The highest reported SAT/ACT scores were from the group that woke up after 7 a.m. but got less than 8 h sleep (M = 1099.5). Their scores were significantly higher than all other groups. This study provides additional evidence that increased sleep and later wake time are associated with increased high school grades. However, this study also found that students who sleep the longest also reported less studying and lower SAT/ACT scores.

Goal Structuring Notation in a Radiation Hardening Assurance Case for COTS-Based Spacecraft

NASA Technical Reports Server (NTRS)

Witulski, Arthur; Austin, Rebekah; Evans, John; Mahadevan, Nag; Karsai, Gabor; Sierawski, Brian; LaBel, Ken; Reed, Robert; Schrimpf, Ron

2016-01-01

A systematic approach is presented to constructing a radiation assurance case using Goal Structuring Notation (GSN) for spacecraft containing commercial-off-the-shelf (COTS) parts. The GSN paradigm is applied to an SRAM single-event upset experiment board designed to fly on a CubeSat November 2016. Construction of a radiation assurance case without use of hardened parts or extensive radiation testing is discussed.

Using Spacecraft in Climate and Natural Disasters Registration

NASA Astrophysics Data System (ADS)

Sokol, Galyna; Kotlov, Vladyslav; Khorischenko, Oleksandr; Davydova, Angelica; Heti, Kristina

2017-04-01

Since the beginning of the space age it become possible the global monitoring of the planet Earth's state. Since the second half of the 20th century there are observations of the atmosphere's state and the Earth's climate have been held by a spacecraft. Also become possible large-scale monitoring of climate change. An attempt was made to define the role of infrasound in the interaction between a space weather, climate and biosphere of the Earth using spacecraft sensors recording. Many countries are involving in the detection of earthquakes, predicting volcanic eruptions and floods and also the monitoring of irregular solar activity. Understanding this leads to the conclusion that international cooperation for the protection of humanity is not only a political priority in the international arena, but also a question of the quality of living standards of any state. Commonly known following monitoring systems: Disaster Monitoring Constellation (DMC), FUEGO program (Spain), Sentinel-Asia program (Japan) and International aerospace system for monitoring of global phenomena (MAKCM, Russia). The Disaster Monitoring Constellation for International Imaging (DMCii) consists of a number of remote sensing satellites constructed by Surrey Satellite Technology Ltd (SSTL) and operated for the Algerian, Nigerian, Turkish, British and Chinese governments by DMC International Imaging. The DMC has monitored the effects and aftermath of the Indian Ocean Tsunami (December 2004), Hurricane Katrina (August 2005), and many other floods, fires and disasters. The individual DMC satellites are: 1. First generation satellites (AlSAT-1 - Algeria, BilSAT - Turkey, NigeriaSAT-1 - Nigeria, UK-DMC - United Kingdom); 2. Second generation satellites (Beijing - China, UK-DMC 2 - United Kingdom, Deimos-1 - Spanish commercial, NigeriaSAT-2 and NigeriaSAT-X). The sun-synchronous orbits of these satellites are coordinated so that the satellites follow each other around an orbital plane, ascending north over the Equator at 10:15 am local time (and 10:30 am local time for Beijing-1). Some of these satellites also include other imaging payloads and experimental payloads: onboard hardware-based image compression (on BilSAT), a GPS reflectometry experiment and onboard Internet router (on the UK-DMC satellite). The DMC satellites are notable for communicating with their ground stations using the Internet Protocol for payload data transfer and command and control, so extending the Internet into space, and allowing experiments with the Interplanetary Internet to be carried out. Many of the technologies used in the design of the DMC satellites, including Internet Protocol use, were tested in space beforehand on SSTL's earlier UoSAT-12 satellite. Currently, there is a great need to establish combining space and ground-based observation systems that will accurately capture key climate variables on a scale from regional to global and stable functioning for decades to determine climate variability and trends. With the help of modern computer systems were calculated moving of infrasonic waves in the atmosphere. This data can be used to predict the weather.

Academic aptitude as a predictor of headache proneness during college: could headache be an outcome of low test scores?

PubMed

Hovanitz, Christine A; Thatcher, Dawn Lindsay

2012-03-01

Academic work as well as compensated employment has been found adversely associated with frequent headache; headache remains a costly disorder to the person and to society. However, little is known of factors--other than prior headache complaints--that may predict headache frequency over extended periods of time. Based on previous research, effortful task engagement appears to be a contributing factor to headache onset. This suggests that relatively stable attributes that are likely to affect effort expenditure may predict headache frequency over long intervals. The goal of this study was to evaluate the predictability of headache proneness in college-attending students by college aptitude tests administered in high school. Five hundred undergraduate students enrolled in a large public, urban university completed a number of questionnaires. Official admissions records of the college aptitude tests ACT (an acronym for the original test name, the American College Testing), SAT (the Scholastic Aptitude Test), and GPA (grade point average) were obtained and compared to the report of headache frequency. The ACT test mathematics predicted headache proneness in the hypothesized direction, while the ACT English test provided conflicting data; some evidence of gender differences was suggested. While nearly all research on headache and work effectiveness has considered headache to be a cause of reduced efficiency or productivity, this study suggests that a factor which presumably affects the ease of work completion (e.g., scholastic aptitude) may predict headache, at least in some cases within the "work" environment of academia.

Status of High Latitude Precipitation Estimates from Observations and Reanalyses

NASA Technical Reports Server (NTRS)

Behrangi, Ali; Christensen, Matthew; Richardson, Mark; Lebsock, Matthew; Stephens, Graeme; Huffman, George J.; Bolvin, David T.; Adler, Robert F.; Gardner, Alex; Lambrigtsen, Bjorn H.;

KSC-05PD-1400

NASA Technical Reports Server (NTRS)

2005-01-01

KENNEDY SPACE CENTER, FLA. Inside the Astrotech Payload Processing Facility on Vandenberg Air Force Base in California, workers hold the Wide Field Camera that they will install on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) spacecraft at right. CALIPSO will fly in combination with the CloudSat satellite to provide never-before-seen 3-D perspectives of how clouds and aerosols form, evolve, and affect weather and climate. CALIPSO and CloudSat will join three other satellites in orbit to enhance understanding of climate systems. The launch date for CALIPSO/CloudSat is no earlier than Aug. 22.

Internal Variability-Generated Uncertainty in East Asian Climate Projections Estimated with 40 CCSM3 Ensembles.

PubMed

Yao, Shuai-Lei; Luo, Jing-Jia; Huang, Gang

2016-01-01

Regional climate projections are challenging because of large uncertainty particularly stemming from unpredictable, internal variability of the climate system. Here, we examine the internal variability-induced uncertainty in precipitation and surface air temperature (SAT) trends during 2005-2055 over East Asia based on 40 member ensemble projections of the Community Climate System Model Version 3 (CCSM3). The model ensembles are generated from a suite of different atmospheric initial conditions using the same SRES A1B greenhouse gas scenario. We find that projected precipitation trends are subject to considerably larger internal uncertainty and hence have lower confidence, compared to the projected SAT trends in both the boreal winter and summer. Projected SAT trends in winter have relatively higher uncertainty than those in summer. Besides, the lower-level atmospheric circulation has larger uncertainty than that in the mid-level. Based on k-means cluster analysis, we demonstrate that a substantial portion of internally-induced precipitation and SAT trends arises from internal large-scale atmospheric circulation variability. These results highlight the importance of internal climate variability in affecting regional climate projections on multi-decadal timescales.

Finite Element Model Optimization of the FalconSAT-5 Structural Engineering Model

DTIC Science & Technology

2009-03-01

for coupled loads analyses. To develop the FE tuning process, this research focuses on the United States Air Force Academy (USAFA) FalconSAT-5 SEM II...Kirtland Air Force Base (KAFB) were sufficient for design engineers to ensure compliance with launch loads. However, for the coupled loads analysis...OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio APPROVED FOR PUBLIC RELEASE; DISTRIBUTION

Polar Satcom System and Related Method

NASA Technical Reports Server (NTRS)

Mitchell, James P. (Inventor)

2016-01-01

A system and method for communication relay via a repeater platform satellite vehicle to a near surface station in the Polar Region is disclosed. A preferred embodiment receives a plurality of positioning and content data from a plurality of constellations of Geosynchronous Equatorial Orbit (GEO) Satellite Vehicles (SAT). Additionally, the system receives a plurality of position, time and altitude data from constellations of available repeater platform (RP) SATs. The system receives a request for content from a near surface station located in an area lacking adequate line-of-sight to the GEO based signal. The system aligns antenna elements onboard the desired RP SATs to amplify and relay the GEO based signal toward the near surface station and vice versa. Additionally, the system commands directional antenna elements onboard the station to send and receive the relayed signal making the GEO based content available to the near surface station.

Retinal oximetry in patients with ischaemic retinal diseases.

PubMed

Rilvén, Sandra; Torp, Thomas Lee; Grauslund, Jakob

2017-03-01

The retinal oximeter is a new tool for non-invasive measurement of retinal oxygen saturation in humans. Several studies have investigated the associations between retinal oxygen saturation and retinal diseases. In the present systematic review, we examine whether there are associations between retinal oxygen saturation and retinal ischaemic diseases. We used PubMed and Embase to search for retinal oxygen saturation and retinal ischaemic diseases. Three separate searches identified a total of 79 publications. After two levels of manual screening, 10 studies were included: six about diabetic retinopathy (DR) and four about retinal vein occlusion. No studies about retinal artery occlusion were included. In diabetes, all studies found that increases in retinal venous oxygen saturation (rvSatO 2 ) were associated with present as well as increasing levels of DR. Four of six studies also found increased retinal arterial oxygen saturation (raSatO 2 ) in patients with DR. In patients with central retinal vein occlusion (CRVO), all studies found that rvSatO 2 was reduced, but raSatO 2 remained unchanged. Branch retinal vein occlusion was not associated with changes in retinal oxygen saturation, but this was based on a single study. In conclusion, DR is associated with increased rvSatO 2 and might also be related to increased raSatO 2 . Central retinal vein occlusion (CRVO) is correlated with increased rvSatO 2 but unrelated to raSatO 2 . Prospective studies are needed to expand these findings. These would tell whether retinal oximetry could be a potential tool for screening or a biomarker of treatment outcome in patients with ischaemic retinal diseases. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

North American wintertime temperature anomalies: the role of El Niño diversity and differential teleconnections

NASA Astrophysics Data System (ADS)

Beyene, Mussie T.; Jain, Shaleen

2018-06-01

El Niño-Southern Oscillation (ENSO) teleconnections induced wintertime surface air temperature (SAT) anomalies over North America show inter-event variability, asymmetry, and nonlinearity. This diagnostic study appraises the assumption that ENSO-induced teleconnections are adequately characterized as symmetric shifts in the SAT probability distributions for North American locations. To this end, a new conditional quantile functional estimation approach presented here incorporates: (a) the detailed nature of location and amplitude of SST anomalies—in particular the Eastern Pacific (EP), Central Pacific (CP) ENSO events—based on its two leading principal components, and (b) over the entire range of SATs, characterize the differential sensitivity to ENSO. Statistical significance is assessed using a wild bootstrap approach. Conditional risk at upper and lower quartile SAT conditioned on archetypical ENSO states is derived. There is marked asymmetry in ENSO effects on the likelihood of upper and lower quartile winter SATs for most North American regions. CP El Niño patterns show 20-80% decrease in the likelihood of lower quartile SATs for Canada and US west coast and a 20-40% increase across southeastern US. However, the upper quartile SAT for large swathes of Canada shows no sensitivity to CP El Niño. Similarly, EP El Niño is linked to a 40-80% increase in the probability of upper quartile winter SATs for Canada and northern US and a 20% decrease for southern US and northern Mexico regions; however, little or no change in the risk of lower quartile winter temperatures for southern parts of North America. Localized estimate of ENSO-related risk are also presented.

CubeSat mission design software tool for risk estimating relationships

NASA Astrophysics Data System (ADS)

Gamble, Katharine Brumbaugh; Lightsey, E. Glenn

2014-09-01

In an effort to make the CubeSat risk estimation and management process more scientific, a software tool has been created that enables mission designers to estimate mission risks. CubeSat mission designers are able to input mission characteristics, such as form factor, mass, development cycle, and launch information, in order to determine the mission risk root causes which historically present the highest risk for their mission. Historical data was collected from the CubeSat community and analyzed to provide a statistical background to characterize these Risk Estimating Relationships (RERs). This paper develops and validates the mathematical model based on the same cost estimating relationship methodology used by the Unmanned Spacecraft Cost Model (USCM) and the Small Satellite Cost Model (SSCM). The RER development uses general error regression models to determine the best fit relationship between root cause consequence and likelihood values and the input factors of interest. These root causes are combined into seven overall CubeSat mission risks which are then graphed on the industry-standard 5×5 Likelihood-Consequence (L-C) chart to help mission designers quickly identify areas of concern within their mission. This paper is the first to document not only the creation of a historical database of CubeSat mission risks, but, more importantly, the scientific representation of Risk Estimating Relationships.

Towards disentangling natural and anthropogenic GHG emissions by space-based atmospheric concentration imaging - The CarbonSat Earth Explorer 8 Candidate Mission

NASA Astrophysics Data System (ADS)

Bovensmann, Heinrich; Gerilowski, Konstantin; Krings, Thomas; Reuter, Max; Burrows, John P.; Buchwitz, Michael; Bösch, Hartmut; Brunner, Dominik; Ciais, Philippe; Breon, Francois-Marie; Crisp, David; Dolman, Han; Hayman, Garry; Houweling, Sander; Lichtenberg, Günter; Ingmann, Paul; Meijer, Yasjka

2013-04-01

CarbonSat was selected by ESA as a candidate for the 8 Earth Explorer Opportunity (EE8). The objective of the CarbonSat mission is to determine natural and anthropogenic sources and sinks of the two most important greenhouse gases, carbon dioxide and methane. The unique features of the CarbonSat mission concept are that it offers a combination of high spatial resolution (2 x 2 km2) and broad swath (240 km) to provide global imaging of localised strong emission source areas such as large cities (Megacities), landfills, power plants, volcanoes, etc. and to be able to separate anthropogenic from natural fluxes. In addition, CarbonSat data will also quantify natural fluxes of CO2 and CH4 (biospheric CO2, wetland CH4 etc.) and their changes, to better understand these important sources and sinks and their sensitivity to a changing climate. CarbonSat aims to deliver global data sets of dry column mixing ratios of CO2 and CH4 with high precision (goal: CO2 < 1 ppm, CH4 < 9 ppb) and accuracy. Benefiting from its imaging capabilities, CarbonSat will provide an at least one order of magnitude larger number of cloud free measurements than GOSAT and OCO and one order of magnitude better spatial coverage than OCO. The CarbonSat mission concept builds on the heritage and lessons learned from SCIAMACHY (2002-2012), GOSAT (2009-present) and OCO-2 (2014 onwards) to make scientifically and strategically important measurements of the amounts and distribution of CO2 and CH4 for biogeochemical and climate change research. CarbonSat entered industrial system feasibility activities in 2012, which are supported by scientific studies and campaigns. The current status of the mission concept and selected results from the scientific studies documenting the expected data quality and characteristics will be presented.

Postembryonic lineages of the Drosophila brain: I. Development of the lineage-associated fiber tracts

PubMed Central

Lovick, Jennifer K.; Ngo, Kathy T.; Omoto, Jaison J.; Wong, Darren C.; Nguyen, Joseph D.; Hartenstein, Volker

2013-01-01

Neurons of the Drosophila central brain fall into approximately 100 paired groups, termed lineages. Each lineage is derived from a single asymmetrically-dividing neuroblast. Embryonic neuroblasts produce 1,500 primary neurons (per hemisphere) that make up the larval CNS followed by a second mitotic period in the larva that generates approximately 10,000 secondary, adult-specific neurons. Clonal analyses based on previous works using lineage-specific Gal4 drivers have established that such lineages form highly invariant morphological units. All neurons of a lineage project as one or a few axon tracts (secondary axon tracts, SATs) with characteristic trajectories, thereby representing unique hallmarks. In the neuropil, SATs assemble into larger fiber bundles (fascicles) which interconnect different neuropil compartments. We have analyzed the SATs and fascicles formed by lineages during larval, pupal, and adult stages using antibodies against membrane molecules (Neurotactin/Neuroglian) and synaptic proteins (Bruchpilot/N-Cadherin). The use of these markers allows one to identify fiber bundles of the adult brain and associate them with SATs and fascicles of the larval brain. This work lays the foundation for assigning the lineage identity of GFP-labeled MARCM clones on the basis of their close association with specific SATs and neuropil fascicles, as described in the accompanying paper (Wong et al., 2013. Postembryonic lineages of the Drosophila brain: II. Identification of lineage projection patterns based on MARCM clones. Submitted.). PMID:23880429

Stand age and species richness dampen interannual variation of ecosystem-level photosynthetic capacity.

PubMed

Musavi, Talie; Migliavacca, Mirco; Reichstein, Markus; Kattge, Jens; Wirth, Christian; Black, T Andrew; Janssens, Ivan; Knohl, Alexander; Loustau, Denis; Roupsard, Olivier; Varlagin, Andrej; Rambal, Serge; Cescatti, Alessandro; Gianelle, Damiano; Kondo, Hiroaki; Tamrakar, Rijan; Mahecha, Miguel D

2017-01-23

The total uptake of carbon dioxide by ecosystems via photosynthesis (gross primary productivity, GPP) is the largest flux in the global carbon cycle. A key ecosystem functional property determining GPP is the photosynthetic capacity at light saturation (GPP sat ), and its interannual variability (IAV) is propagated to the net land-atmosphere exchange of CO 2 . Given the importance of understanding the IAV in CO 2 fluxes for improving the predictability of the global carbon cycle, we have tested a range of alternative hypotheses to identify potential drivers of the magnitude of IAV in GPP sat in forest ecosystems. Our results show that while the IAV in GPP sat within sites is closely related to air temperature and soil water availability fluctuations, the magnitude of IAV in GPP sat is related to stand age and biodiversity (R 2 = 0.55, P < 0.0001). We find that the IAV of GPP sat is greatly reduced in older and more diverse forests, and is higher in younger forests with few dominant species. Older and more diverse forests seem to dampen the effect of climate variability on the carbon cycle irrespective of forest type. Preserving old forests and their diversity would therefore be beneficial in reducing the effect of climate variability on Earth's forest ecosystems.

A Low Cost Inflatable CubeSat Drag Brake Utilizing Sublimation

NASA Astrophysics Data System (ADS)

Horn, Adam Charles

The United Nations Inter-Agency Debris Coordination Committee has adopted a 25-year post-mission lifetime requirement for any satellite orbiting below 2000 km in order to mitigate the growing orbital debris threat. Low-cost CubeSats have become important satellite platforms with startling capabilities, but this guideline restricts them to altitudes below 600 km because they remain in orbit too long. In order to enable CubeSat deployments at higher release altitudes, a low-cost, ultra-reliable deorbit device is needed. This thesis reports on efforts to develop a deployable and passively inflatable drag brake that can deorbit from higher orbital altitudes, thereby complying with the 25-year orbital lifetime guideline. On the basis of concepts first implemented during the NASA Echo Satellite Project, this study investigated the design of an inflatable CubeSat drag device that utilizes sublimating benzoic acid powder as the inflation propellant. Testing has focused on demonstrating the functionality of charging a Mylar drag brake bladder with appropriate quantities of benzoic acid powder, and the exposure to a controlled-temperature vacuum chamber causing the bladder to inflate. Although results show a measureable increase in internal pressure when introduced to anticipated orbital temperatures, a significant air-derived expansion prior to sublimation was encountered due to the undetectable volume of ambient residual air in the fabricated membrane bladders. These tests have demonstrated the feasibility of this approach, thereby demonstrating that this concept can create a potentially smaller and less expensive drag device, eliminating inflation gas tanks and valves. In that way, this system can provide a low-cost, miniaturized system that reduces a CubeSat's orbital lifetime to less than 25 years, when placed at higher orbital altitude.

Comparison of virtual reality exergaming and home exercise programs in patients with subacromial impingement syndrome and scapular dyskinesis: Short term effect.

PubMed

Pekyavas, Nihan Ozunlu; Ergun, Nevin

2017-05-01

The aim of this study was to compare the short term effects of home exercise program and virtual reality exergaming in patients with subacromial impingement syndrome (SAIS). A total of 30 patients with SAIS were randomized into two groups which are Home Exercise Program (EX Group) (mean age: 40.6 ± 11.7 years) and Virtual Reality Exergaming Program (WII Group) (mean age: 40.33 ± 13.2 years). Subjects were assessed at the first session, at the end of the treatment (6 weeks) and at 1 month follow-up. The groups were assessed and compared with Visual Analogue Scale (based on rest, activity and night pain), Neer and Hawkins Tests, Scapular Retraction Test (SRT), Scapular Assistance Test (SAT), Lateral Scapular Slide Test (LSST) and shoulder disability (Shoulder Pain and Disability Index (SPADI)). Intensity of pain was significantly decreased in both groups with the treatment (p < 0.05). The WII Group had significantly better results for all Neer test, SRT and SAT than the EX Group (p < 0.05). Virtual reality exergaming programs with these programs were found more effective than home exercise programs at short term in subjects with SAIS. Level I, Therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

Satellite-Based Quantum Communications

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

Hughes, Richard J; Nordholt, Jane E; McCabe, Kevin P

2010-09-20

Single-photon quantum communications (QC) offers the attractive feature of 'future proof', forward security rooted in the laws of quantum physics. Ground based quantum key distribution (QKD) experiments in optical fiber have attained transmission ranges in excess of 200km, but for larger distances we proposed a methodology for satellite-based QC. Over the past decade we have devised solutions to the technical challenges to satellite-to-ground QC, and we now have a clear concept for how space-based QC could be performed and potentially utilized within a trusted QKD network architecture. Functioning as a trusted QKD node, a QC satellite ('QC-sat') could deliver secretmore » keys to the key stores of ground-based trusted QKD network nodes, to each of which multiple users are connected by optical fiber or free-space QC. A QC-sat could thereby extend quantum-secured connectivity to geographically disjoint domains, separated by continental or inter-continental distances. In this paper we describe our system concept that makes QC feasible with low-earth orbit (LEO) QC-sats (200-km-2,000-km altitude orbits), and the results of link modeling of expected performance. Using the architecture that we have developed, LEO satellite-to-ground QKD will be feasible with secret bit yields of several hundred 256-bit AES keys per contact. With multiple ground sites separated by {approx} 100km, mitigation of cloudiness over any single ground site would be possible, potentially allowing multiple contact opportunities each day. The essential next step is an experimental QC-sat. A number of LEO-platforms would be suitable, ranging from a dedicated, three-axis stabilized small satellite, to a secondary experiment on an imaging satellite. to the ISS. With one or more QC-sats, low-latency quantum-secured communications could then be provided to ground-based users on a global scale. Air-to-ground QC would also be possible.« less

Amoeba-Inspired Heuristic Search Dynamics for Exploring Chemical Reaction Paths.

PubMed

Aono, Masashi; Wakabayashi, Masamitsu

2015-09-01

We propose a nature-inspired model for simulating chemical reactions in a computationally resource-saving manner. The model was developed by extending our previously proposed heuristic search algorithm, called "AmoebaSAT [Aono et al. 2013]," which was inspired by the spatiotemporal dynamics of a single-celled amoeboid organism that exhibits sophisticated computing capabilities in adapting to its environment efficiently [Zhu et al. 2013]. AmoebaSAT is used for solving an NP-complete combinatorial optimization problem [Garey and Johnson 1979], "the satisfiability problem," and finds a constraint-satisfying solution at a speed that is dramatically faster than one of the conventionally known fastest stochastic local search methods [Iwama and Tamaki 2004] for a class of randomly generated problem instances [ http://www.cs.ubc.ca/~hoos/5/benchm.html ]. In cases where the problem has more than one solution, AmoebaSAT exhibits dynamic transition behavior among a variety of the solutions. Inheriting these features of AmoebaSAT, we formulate "AmoebaChem," which explores a variety of metastable molecules in which several constraints determined by input atoms are satisfied and generates dynamic transition processes among the metastable molecules. AmoebaChem and its developed forms will be applied to the study of the origins of life, to discover reaction paths for which expected or unexpected organic compounds may be formed via unknown unstable intermediates and to estimate the likelihood of each of the discovered paths.

Assessing the speed--accuracy trade-off effect on the capacity of information processing.

PubMed

Donkin, Chris; Little, Daniel R; Houpt, Joseph W

2014-06-01

The ability to trade accuracy for speed is fundamental to human decision making. The speed-accuracy trade-off (SAT) effect has received decades of study, and is well understood in relatively simple decisions: collecting more evidence before making a decision allows one to be more accurate but also slower. The SAT in more complex paradigms has been given less attention, largely due to limits in the models and statistics that can be applied to such tasks. Here, we have conducted the first analysis of the SAT in multiple signal processing, using recently developed technologies for measuring capacity that take into account both response time and choice probability. We show that the primary influence of caution in our redundant-target experiments is on the threshold amount of evidence required to trigger a response. However, in a departure from the usual SAT effect, we found that participants strategically ignored redundant information when they were forced to respond quickly, but only when the additional stimulus was reliably redundant. Interestingly, because the capacity of the system was severely limited on redundant-target trials, ignoring additional targets meant that processing was more efficient when making fast decisions than when making slow and accurate decisions, where participants' limited resources had to be divided between the 2 stimuli. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Preliminary Validation of the Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Concept

NASA Technical Reports Server (NTRS)

Williams, Daniel; Consiglio, Maria; Murdoch, Jennifer; Adams, Catherine

2004-01-01

This document provides a preliminary validation of the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept for normal conditions. Initial results reveal that the concept provides reduced air traffic delays when compared to current operations without increasing pilot workload. Characteristic to the SATS HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA) which would be activated by air traffic control (ATC) around designated non-towered, non-radar airports. During periods of poor visibility, SATS pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft in the SCA. Using onboard equipment and simple instrument flight procedures, they would then be better able to approach and land at the airport or depart from it. This concept would also require a new, ground-based automation system, typically located at the airport that would provide appropriate sequencing information to the arriving aircraft. Further validation of the SATS HVO concept is required and is the subject of ongoing research and subsequent publications.

Impact of the Winter North Pacific Oscillation on the Surface Air Temperature over Eurasia and North America: Sensitivity to the Index Definition

NASA Astrophysics Data System (ADS)

Chen, Shangfeng; Song, Linye

2018-06-01

This study analyzes the impact of the winter North Pacific Oscillation (NPO) on the surface air temperature (SAT) variations over Eurasia and North America based on six different NPO indices. Results show that the influences of the winter NPO on the SAT over Eurasia and North America are sensitive to the definition of the NPO index. The impact of the winter NPO on the SAT variations over Eurasia (North America) is significant (insignificant) when the anticyclonic anomaly associated with the NPO index over the North Pacific midlatitudes shifts westward and pronounced northerly wind anomalies appear around Lake Baikal. By contrast, the impact of the winter NPO on the SAT variations over Eurasia (North America) is insignificant (significant) when the anticyclonic anomaly over the North Pacific related to the NPO index shifts eastward and the associated northerly wind anomalies to its eastern flank extend to North America. The present study suggests that the NPO definition should be taken into account when analyzing the impact of the winter NPO on Eurasian and North American SAT variations.

Perceptions of doctors and nurses at a Ugandan hospital regarding the introduction and use of the South African Triage Scale.

PubMed

Mulindwa, Francis; Blitz, Julia

2016-03-29

International Hospital Kampala (IHK) experienced a challenge with how to standardise the triaging and sorting of patients. There was no triage tool to help to prioritise which patients to attend to first, with very sick patient often being missed. To explore whether the introduction of the South African Triage Scale (SATS) was seen as valuable and sustainable by the IHK's outpatient department and emergency unit (OPD and EU) staff. The study used qualitative methods to introduce SATS in the OPD and EU at IHK and to obtain the perceptions of doctors and nurses who had used it for 3-6 months on its applicability and sustainability. Specific questions about challenges faced prior to its introduction, strengths and weaknesses of the triage tool, the impact it had on staff practices, and their recommendations on the continued use of the tool were asked. In-depth interviews were conducted with 4 doctors and 12 nurses. SATS was found to be necessary, applicable and recommended for use in the IHK setting. It improved the sorting of patients, as well as nurse-patient and nurse-doctor communication.The IHK OPD & EU staff attained new skills, with nurses becoming more involved in-patient care. It is possibly also useful in telephone triaging and planning of hospital staffing. Adequate nurse staffing, a computer application for automated coding of patients, and regular training would encourage consistent use and sustainability of SATS. Setting up a hospital committee to review signs and symptoms would increase acceptability and sustainability. SATS is valuable in the IHK setting because it improved overall efficiency of triaging and care, with significantly more strengths than weaknesses.

MarCOs, Mars and Earth

NASA Image and Video Library

2018-03-29

An artist's rendering of the twin Mars Cube One (MarCO) spacecraft flying over Mars with Earth in the distance. The MarCOs will be the first CubeSats -- a kind of modular, mini-satellite -- flown in deep space. They're designed to fly along behind NASA's InSight lander on its cruise to Mars. If they make the journey, they will test a relay of data about InSight's entry, descent and landing back to Earth. Though InSight's mission will not depend on the success of the MarCOs, they will be a test of how CubeSats can be used in deep space. https://photojournal.jpl.nasa.gov/catalog/PIA22316

Nigeria's Satellite Programme Development: Prospects and Challenges

NASA Astrophysics Data System (ADS)

Akinyede, Joseph

Nigeria's desire to maximize the benefits of space technology for its sustainable development, has become a reality with the establishment of the National Space Research and Development Agency (NASRDA) in May 1999 and the approval of the national Space Policy and Programmes in July 2001. In November, 2000, the Federal Government took a bold step with the signing of an agreement with the Surrey Satellite Technology Limited (SSTL) of United Kingdom (UK) for the design, construction and launch of a medium resolution micro-satellite - NigeriaSat-1 with a Ground Sampling Distance of thirty-two (32) meters. The agreement also covers the Know-How-Technology-Training (KHTT) to Nigerian Engineers and Scientists for a period of 18th months at SSTL‘s facility in the U.K.. NigeriaSat-1 was successfully launched into Leo Earth Orbit on 27th September, 2003. NigeriaSat- 1 is one of the five (5) satellites belonging to Nigeria, Algeria, Turkey, United Kingdom and China being operated in a Disaster Monitoring Constellation (DMC). The launch of NigeriaSat-1 has promoted access to information which has become a strategy for mass socio-economic development, as information underscores all developmental effort be it in education, provision of health services, marketing, construction industry, tourism, defense, etc. As a follow-up to the successful launch of NigeriaSat-1, the government of Nigeria started the implementation of a Nigerian communication satellite (NigcomSat-1) to address the problem of communication which is the greatest drawbacks to the socio-economic development of the country, particularly in the areas of rural telephone, tele-education, tele-medicine, egovernment, e-commerce and real-time monitoring services. NigcomSat-1, which carries 40- hybrid transponders in the C, KU, KA and L bands, has a 15 years life span and coverage of the African continent, Middle East and part of Europe was launched in May 2007. To satisfy geospatial data needs in sectors such as survey, housing, defence and security and urban renewal, and large scale mapping community, NASRDA has embarked on the development of a higher resolution satellite NigeriaSat-2 which carries spatial resolution pay loads of 2.5 and 5 meters in panchromatic and multi-spectral bands respectively. In addition, the satellite has been designed to provide stereo-imaging capability. It also carries a 32m resolution payload to ensure the continuity of NigeriaSat-1 data beyond its 2008 lifespan. The launch of NigeriaSat-2 is being planned for 2009. Furthermore, Nigeria's concern over the incessant cloud cover of a large area of its southern part has informed NASRDA's quest to acquire capacity for SAR-based image interpretation and application to socio-economic development. The programme will eventually lead to the acquisition of a SAR-based micro-satellite (NigeriaSat-3) in the near future.

KSC-2013-2714

NASA Image and Video Library

2013-06-10

SAN LUIS OBISPO, Calif. – Jim Kinney, a NASA mentor for the student launch team of the StangSat, works inside the CubeSat lab facility at California Polytechnic Institute, or CalPoly. The payload, which includes sensors and equipment carefully packaged into 4-inch cubes, will ride in the body of a Garvey Spacecraft Corporation's Prospector P-18D rocket during a June 15 launch on a high-altitude, suborbital flight. Known as a CubeSat, the StangSat will record shock, vibrations and heat inside the rocket. It will not be released during the test flight, but the results will be used to prove or strengthen the design before it is carried into orbit in 2014 on a much larger rocket. A new, lightweight carrier is also being tested for use on future missions to deploy the small spacecraft. The flight also is being watched closely as a model for trying out new or off-the-shelf technologies quickly before putting them in the pipeline for use on NASA's largest launchers. Built by several different organizations, including a university, a NASA field center and a high school, the spacecraft are four-inch cubes designed to fly on their own eventually, but will remain firmly attached to the rocket during the upcoming mission. For more information, visit http://www.nasa.gov/mission_pages/smallsats/elana/cubesatlaunchpreview.html Photo credit: VAFB/Kathi Peoples

Science Results and Lessons Learned from CubeSat: Colorado Space Weather Experiment (CSSWE)

NASA Astrophysics Data System (ADS)

Li, Xinlin

The Relativistic Electron and Proton Telescope integrated little experiment (REPTile) is a loaded-disc collimated solid-state particle telescope, designed, built, tested, and operated by a team of students at the University of Colorado. It is the only science payload onboard the Colorado Student Space Weather Experiment (CSSWE), a 3U CubeSat (10cm x 10cm x 30cm) launched into a low-Earth, 480km x 780km, and highly inclined (65 deg) orbit on 13 September 2012. REPTile measures differential fluxes of 0.58 to >3.8 MeV electrons and 9-40 MeV protons. These measurements, by themselves and in conjunction with other larger missions, are critical to understand the dynamics of these energetic particles. Miniaturizing a power- and mass-hungry particle telescope to return clean measurements from a CubeSat platform is challenging. To overcome these challenges, REPTile underwent a rigorous design and testing phase. Despite the limitations inherent with CubeSats, REPTile to date (still in operation) has returned more than 300 days of valuable science data, more than tripling its nominal mission lifetime of 90 days. The data are clean, as REPTile is able to clearly distinguish between particle species. Important science results using REPTile data, some of which have been published in peer-reviewed journals, will be presented in this presentation.

The Nano-Sat Exo-Brake Experiment: Status of the First Controlled De-Orbit (and Subsequent Experiments)

NASA Technical Reports Server (NTRS)

Murbach, M.; Guarneros Luna, A.; Alena, R.; Papadopoulos, P.; Stone, T.; Tanner, A.; Wheless, J.; Priscal, C.; Dono Perez, A.; Cianciolo, A;

A Physically Based Algorithm for Non-Blackbody Correction of Cloud-Top Temperature and Application to Convection Study

NASA Technical Reports Server (NTRS)

Wang, Chunpeng; Lou, Zhengzhao Johnny; Chen, Xiuhong; Zeng, Xiping; Tao, Wei-Kuo; Huang, Xianglei

2014-01-01

Cloud-top temperature (CTT) is an important parameter for convective clouds and is usually different from the 11-micrometers brightness temperature due to non-blackbody effects. This paper presents an algorithm for estimating convective CTT by using simultaneous passive [Moderate Resolution Imaging Spectroradiometer (MODIS)] and active [CloudSat 1 Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO)] measurements of clouds to correct for the non-blackbody effect. To do this, a weighting function of the MODIS 11-micrometers band is explicitly calculated by feeding cloud hydrometer profiles from CloudSat and CALIPSO retrievals and temperature and humidity profiles based on ECMWF analyses into a radiation transfer model.Among 16 837 tropical deep convective clouds observed by CloudSat in 2008, the averaged effective emission level (EEL) of the 11-mm channel is located at optical depth; approximately 0.72, with a standard deviation of 0.3. The distance between the EEL and cloud-top height determined by CloudSat is shown to be related to a parameter called cloud-top fuzziness (CTF), defined as the vertical separation between 230 and 10 dBZ of CloudSat radar reflectivity. On the basis of these findings a relationship is then developed between the CTF and the difference between MODIS 11-micrometers brightness temperature and physical CTT, the latter being the non-blackbody correction of CTT. Correction of the non-blackbody effect of CTT is applied to analyze convective cloud-top buoyancy. With this correction, about 70% of the convective cores observed by CloudSat in the height range of 6-10 km have positive buoyancy near cloud top, meaning clouds are still growing vertically, although their final fate cannot be determined by snapshot observations.

Testing the implementation and sustainment facilitation (ISF) strategy as an effective adjunct to the Addiction Technology Transfer Center (ATTC) strategy: study protocol for a cluster randomized trial.

PubMed

Garner, Bryan R; Zehner, Mark; Roosa, Mathew R; Martino, Steve; Gotham, Heather J; Ball, Elizabeth L; Stilen, Patricia; Speck, Kathryn; Vandersloot, Denna; Rieckmann, Traci R; Chaple, Michael; Martin, Erika G; Kaiser, David; Ford, James H

2017-11-17

Improving the extent to which evidence-based practices (EBPs)-treatments that have been empirically shown to be efficacious or effective-are integrated within routine practice is a well-documented challenge across numerous areas of health. In 2014, the National Institute on Drug Abuse funded a type 2 effectiveness-implementation hybrid trial titled the substance abuse treatment to HIV Care (SAT2HIV) Project. Aim 1 of the SAT2HIV Project tests the effectiveness of a motivational interviewing-based brief intervention (MIBI) for substance use as an adjunct to usual care within AIDS service organizations (ASOs) as part of its MIBI Experiment. Aim 2 of the SAT2HIV Project tests the effectiveness of implementation and sustainment facilitation (ISF) as an adjunct to the Addiction Technology Transfer Center (ATTC) model for training staff in motivational interviewing as part of its ISF Experiment. The current paper describes the study protocol for the ISF Experiment. Using a cluster randomized design, case management and leadership staff from 39 ASOs across the United States were randomized to receive either the ATTC strategy (control condition) or the ATTC + ISF strategy (experimental condition). The ATTC strategy is staff-focused and includes 10 discrete strategies (e.g., provide centralized technical assistance, conduct educational meetings, provide ongoing consultation). The ISF strategy is organization-focused and includes seven discrete strategies (e.g., use an implementation advisor, organize implementation team meetings, conduct cyclical small tests of change). Building upon the exploration-preparation-implementation-sustainment (EPIS) framework, the effectiveness of the ISF strategy is examined via three staff-level measures: (1) time-to-proficiency (i.e., preparation phase outcome), (2) implementation effectiveness (i.e., implementation phase outcome), and (3) level of sustainment (i.e., sustainment phase outcome). Although not without limitations, the ISF experiment has several strengths: a highly rigorous design (randomized, hypothesis-driven), high-need setting (ASOs), large sample size (39 ASOs), large geographic representation (23 states and the District of Columbia), and testing along multiple phases of the EPIS continuum (preparation, implementation, and sustainment). Thus, study findings will significantly improve generalizable knowledge regarding the best preparation, implementation, and sustainment strategies for advancing EBPs along the EPIS continuum. Moreover, increasing ASO's capacity to address substance use may improve the HIV Care Continuum. Trial registration ClinicalTrials.gov: NCT03120598.

Generation and analysis of correlated pairs of photons on board a nanosatellite

NASA Astrophysics Data System (ADS)

Chandrasekara, R.; Tang, Z.; Tan, Y. C.; Cheng, C.; Sha, L.; Hiang, G. C.; Oi, D.; Ling, A.

2016-10-01

Progress in quantum computers and their threat to conventional public key infrastructure is driving new forms of encryption. Quantum Key Distribution (QKD) using entangled photons is a promising approach. A global QKD network can be achieved using satellites equipped with optical links. Despite numerous proposals, actual experimental work demonstrating relevant entanglement technology in space is limited due to the prohibitive cost of traditional satellite development. To make progress, we have designed a photon pair source that can operate on modular spacecraft called CubeSats. We report the in-orbit operation of the photon pair source on board an orbiting CubeSat and demonstrate pair generation and polarisation correlation under space conditions. The in-orbit polarisation correlations are compatible with ground-based tests, validating our design. This successful demonstration is a major experimental milestone towards a space-based quantum network. Our approach provides a cost-effective method for proving the space-worthiness of critical components used in entangled photon technology. We expect that it will also accelerate efforts to probe the overlap between quantum and relativistic models of physics.

Identification of common, unique and polymorphic microsatellites among 73 cyanobacterial genomes.

PubMed

Kabra, Ritika; Kapil, Aditi; Attarwala, Kherunnisa; Rai, Piyush Kant; Shanker, Asheesh

2016-04-01

Microsatellites also known as Simple Sequence Repeats are short tandem repeats of 1-6 nucleotides. These repeats are found in coding as well as non-coding regions of both prokaryotic and eukaryotic genomes and play a significant role in the study of gene regulation, genetic mapping, DNA fingerprinting and evolutionary studies. The availability of 73 complete genome sequences of cyanobacteria enabled us to mine and statistically analyze microsatellites in these genomes. The cyanobacterial microsatellites identified through bioinformatics analysis were stored in a user-friendly database named CyanoSat, which is an efficient data representation and query system designed using ASP.net. The information in CyanoSat comprises of perfect, imperfect and compound microsatellites found in coding, non-coding and coding-non-coding regions. Moreover, it contains PCR primers with 200 nucleotides long flanking region. The mined cyanobacterial microsatellites can be freely accessed at www.compubio.in/CyanoSat/home.aspx. In addition to this 82 polymorphic, 13,866 unique and 2390 common microsatellites were also detected. These microsatellites will be useful in strain identification and genetic diversity studies of cyanobacteria.

CFD and Thermo Mechanical Analysis on Effect of Curved vs Step Surface in IC Engine Cylinder Head

NASA Astrophysics Data System (ADS)

Balaji, S.; Ganesh, N.; Kumarasamy, A.

2017-05-01

Current research in IC engines mainly focus on various methods to achieve higher efficiency and high specific power. As a single design parameter, combustion chamber peak spring pressure has increased more than before. Apart from the structural aspects of withstanding these loads, designer faces challenges of resolving thermal aspects of cylinder head. Methods to enhance the heat transfer without compromising load withstanding capability are being constantly explored. Conventional cylinder heads have got sat inner surface. In this paper we have suggested a modification in inner surface to enhance the heat transfer capability. To increase the heat transfer rate, inner same deck surface is configured as a curved and stepped surface instead of sat. We have reported the effectiveness of extend of curvature in the inner same deck surface in a different technical paper. Here, we are making a direct comparison between stepped and curved surface only. From this analysis it has been observed that curved surface reduces the ame deck temperature considerably without compromising the structural strength factors compared to step and sat surface.

VANDENBERG AIR FORCE BASE, CALIF. - At Vandenberg Air Force Base, Calif. a covered SciSat-1 spacecraft is lifted onto a rotation stand. The solar arrays will be attached and the communications systems checked out. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-07-29

VANDENBERG AIR FORCE BASE, CALIF. - At Vandenberg Air Force Base, Calif. a covered SciSat-1 spacecraft is lifted onto a rotation stand. The solar arrays will be attached and the communications systems checked out. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

³Cat-3/MOTS Nanosatellite Mission for Optical Multispectral and GNSS-R Earth Observation: Concept and Analysis.

PubMed

Castellví, Jordi; Camps, Adriano; Corbera, Jordi; Alamús, Ramon

2018-01-06

The ³Cat-3/MOTS (3: Cube, Cat: Catalunya, 3: 3rd CubeSat mission/Missió Observació Terra Satèl·lit) mission is a joint initiative between the Institut Cartogràfic i Geològic de Catalunya (ICGC) and the Universitat Politècnica de Catalunya-BarcelonaTech (UPC) to foster innovative Earth Observation (EO) techniques based on data fusion of Global Navigation Satellite Systems Reflectometry (GNSS-R) and optical payloads. It is based on a 6U CubeSat platform, roughly a 10 cm × 20 cm × 30 cm parallelepiped. Since 2012, there has been a fast growing trend to use small satellites, especially nanosatellites, and in particular those following the CubeSat form factor. Small satellites possess intrinsic advantages over larger platforms in terms of cost, flexibility, and scalability, and may also enable constellations, trains, federations, or fractionated satellites or payloads based on a large number of individual satellites at an affordable cost. This work summarizes the mission analysis of ³Cat-3/MOTS, including its payload results, power budget (PB), thermal budget (TB), and data budget (DB). This mission analysis is addressed to transform EO data into territorial climate variables (soil moisture and land cover change) at the best possible achievable spatio-temporal resolution.

Multidirectional Cosmic Ray Ion Detector for Deep Space CubeSats

NASA Technical Reports Server (NTRS)

Wrbanek, John D.; Wrbanek, Susan Y.

2016-01-01

NASA Glenn Research Center has proposed a CubeSat-based instrument to study solar and cosmic ray ions in lunar orbit or deep space. The objective of Solar Proton Anisotropy and Galactic cosmic ray High Energy Transport Instrument (SPAGHETI) is to provide multi-directional ion data to further understand anisotropies in SEP and GCR flux.

CANSAT: Design of a Small Autonomous Sounding Rocket Payload

NASA Technical Reports Server (NTRS)

Berman, Joshua; Duda, Michael; Garnand-Royo, Jeff; Jones, Alexa; Pickering, Todd; Tutko, Samuel

2009-01-01

CanSat is an international student design-build-launch competition organized by the American Astronautical Society (AAS) and American Institute of Aeronautics and Astronautics (AIAA). The competition is also sponsored by the Naval Research Laboratory (NRL), the National Aeronautics and Space Administration (NASA), AGI, Orbital Sciences Corporation, Praxis Incorporated, and SolidWorks. Specifically, the 2009 Virginia Tech CanSat Team is funded by BAE Systems, Incorporated of Manassas, Virginia. The objective of the 2009 CanSat competition is to complete remote sensing missions by designing a small autonomous sounding rocket payload. The payload designed will follow and perform to a specific set of mission requirements for the 2009 competition. The competition encompasses a complete life-cycle of one year which includes all phases of design, integration, testing, reviews, and launch.

Monitoring the High-Energy Radiation Environment of Exoplanets around Lowmass Stars with SPARCS (Star-Planet Activity Research CubeSat)

NASA Astrophysics Data System (ADS)

Shkolnik, Evgenya

Seventy-five billion M dwarfs in our galaxy host at least one small planet in the habitable zone (HZ). The stellar ultraviolet (UV) radiation from M dwarfs is strong and highly variable, and impacts planetary atmospheric loss, composition and habitability. These effects are amplified by the extreme proximity of their HZs (0.1–0.4 AU). JWST will characterize HZ M dwarf planets and attempt the first spectroscopic search for life beyond the Solar System. Knowing the UV environments of M dwarf planets will be crucial to understanding their atmospheric composition and a key parameter in discriminating between biological and abiotic sources for observed biosignatures. The UV flux emitted during the super-luminous premain sequence phase of M stars drives water loss and photochemical O2 buildup for terrestrial planets within the HZ. This phase can persist for up to a billion years for the lowest mass M stars. Afterwards, UV-driven photochemistry during the main sequence phase strongly affects a planet’s atmosphere, could limit the planet’s potential for habitability, and may confuse studies of habitability by creating false chemical biosignatures. Our proposed CubeSat observatory will be the first mission to provide the time-dependent spectral slope, intensity and evolution of M dwarf stellar UV radiation. These measurements are crucial to interpreting observations of planetary atmospheres around low-mass stars. Mission: The Star-Planet Activity Research CubeSat (SPARCS) will be a 6U CubeSat devoted to monitoring 25 M stars in two UV bands: SPARCS far-UV (S- FUV: 153–171 nm) and SPARCS near-UV (S-NUV: 260– 300 nm). For each target, SPARCS will observe continuously between one and three complete stellar rotations (4–45 days) over a mission lifetime of 2 years. A UV characterization survey of M dwarfs, the most common of planet hosts, is a perfect experiment for a CubeSat: - UV astronomy cannot be done from the ground because of Earth’s atmospheric absorption. - Photometry of nearby sources is an efficient use of a small aperture. - Unlike the HST, whose time is shared among many instruments and programs, a CubeSat can provide dedicated space-based long-term monitoring in the UV. Technology: SPARCS will advance UV detector technology by flying high quantum efficiency (QE), UV-optimized detectors developed at JPL. These “delta-doped” detectors have a long history of deployment demonstrating greater than 5x the sensitivity of the detectors used by GALEX. SPARCS will pave the way for their application in missions like LUVOIR or HabEx. Education: The SPARCS research program will train future scientists and mission leaders by mentoring five undergraduate students, three graduate students, and two post-doctoral scholars throughout all aspects of the mission, including engineering, science, data management and outreach. Relevance to NASA: The SPARCS mission will address NASA’s goals of identifying the characteristics and distribution of potentially habitable environments, including HZ planet hosts like Proxima and TRAPPIST-1. SPARCS will also be capable of ‘targetofopportunity’ UV observations of NASA’s TESS yield of rocky planets in M dwarf HZs, some of the first HZ planets to be spectroscopically characterized by JWST. SPARCS can provide the needed UV context for the interpretation of transmission and emission spectra of these potentially habitable planets. Further into the future, SPARCS results will inform the target strategy for the enormous telescopic investments in exoplanet science of LUVOIR or HabEx. SPARCS’ technology will fill a gap in NASA’s capabilities to observe low-mass stellar/planetary systems in the FUV and NUV. HST’s UV capabilities will not last much later than 2019, with future opportunities (e.g., LUVOIR) not arriving until sometime after 2035. The detector technology of this CubeSat will play a crucial role in these and interim UV-capable missions.

Reconciling CloudSat and GPM Estimates of Falling Snow

NASA Technical Reports Server (NTRS)

Munchak, S. Joseph; Jackson, Gail Skofronick; Kulie, Mark; Wood, Norm; Miliani, Lisa

2017-01-01

Satellite-based estimates of falling snow have been provided by CloudSat (launched in 2006) and the Global Precipitation Measurement (GPM) core satellite (launched in 2014). The CloudSat estimates are derived from W-band radar measurements whereas the GPM estimates are derived from its scanning Ku- and Ka-band Dual-Frequency Precipitation Radar (DPR) and 13-channel microwave imager (GMI). Each platform has advantages and disadvantages: CloudSat has higher resolution (approximately 1.5 km) and much better sensitivity (-28 dBZ), but poorer sampling (nadir-only and daytime-only since 2011) and the reflectivity-snowfall (Z-S) relationship is poorly constrained with single-frequency measurements. Meanwhile, DPR suffers from relatively poor resolution (5 km) and sensitivity (approximately 13 dBZ), but has cross-track scanning capability to cover a 245-km swath. Additionally, where Ku and Ka measurements are available, the conversion of reflectivity to snowfall rate is better-constrained than with a single frequency.

Unrecognized circulation of SAT 1 foot-and-mouth disease virus in cattle herds around Queen Elizabeth National Park in Uganda.

PubMed

Dhikusooka, Moses Tefula; Ayebazibwe, Chrisostom; Namatovu, Alice; Belsham, Graham J; Siegismund, Hans Redlef; Wekesa, Sabenzia Nabalayo; Balinda, Sheila Nina; Muwanika, Vincent B; Tjørnehøj, Kirsten

2016-01-06

Foot-and-mouth disease (FMD) is endemic in Uganda in spite of the control measures used. Various aspects of the maintenance and circulation of FMD viruses (FMDV) in Uganda are not well understood; these include the role of the African buffalo (Syncerus caffer) as a reservoir for FMDV. To better understand the epidemiology of FMD at the livestock-wildlife-interface, samples were collected from young, unvaccinated cattle from 24 pastoral herds that closely interact with wildlife around Queen Elizabeth National Park in Uganda, and analysed for evidence of FMDV infection. In total, 37 (15%) of 247 serum samples had detectable antibodies against FMDV non-structural proteins (NSPs) using a pan-serotypic assay. Within these 37 sera, antibody titres ≥ 80 against the structural proteins of serotypes O, SAT 1, SAT 2 and SAT 3 were detected by ELISA in 5, 7, 4 and 3 samples, respectively, while neutralizing antibodies were only detected against serotype O in 3 samples. Two FMDV isolates, with identical VP1 coding sequences, were obtained from probang samples from clinically healthy calves from the same herd and are serotype SAT 1 (topotype IV (EA-I)). Based on the VP1 coding sequences, these viruses are distinct from previous cattle and buffalo SAT 1 FMDV isolates obtained from the same area (19-30% nucleotide difference) and from the vaccine strain (TAN/155/71) used within Uganda (26% nucleotide difference). Eight herds had only one or a few animals with antibodies against FMDV NSPs while six herds had more substantial evidence of prior infection with FMDV. There was no evidence for exposure to FMDV in the other ten herds. The two identical SAT 1 FMDV VP1 sequences are distinct from former buffalo and cattle isolates from the same area, thus, transmission between buffalo and cattle was not demonstrated. These new SAT 1 FMDV isolates differed significantly from the vaccine strain used to control Ugandan FMD outbreaks, indicating a need for vaccine matching studies. Only six herds had clear serological evidence for exposure to O and SAT 1 FMDV. Scattered presence of antibodies against FMDV in other herds may be due to the occasional introduction of animals to the area or maternal antibodies from past infection and/or vaccination. The evidence for asymptomatic FMDV infection has implications for disease control strategies in the area since this obstructs early disease detection that is based on clinical signs in FMDV infected animals.

The Tests and the "Brightest." How Fair Are the College Boards?

ERIC Educational Resources Information Center

Fallows, James

1980-01-01

The role of standardized tests in American education is being challenged as many feel that they are unfair and actually reinforce and legitimize existing inequalities. The Educational Testing Service, the SAT, meritocracy, test coaching, and economic bias are discussed. (MLW)

The ability for cocaine and cocaine-associated cues to compete for attention

PubMed Central

Pitchers, Kyle K.; Wood, Taylor R.; Skrzynski, Cari J.; Robinson, Terry E.; Sarter, Martin

2017-01-01

In humans, reward cues, including drug cues in addicts, are especially effective in biasing attention towards them, so much so they can disrupt ongoing task performance. It is not known, however, whether this happens in rats. To address this question, we developed a behavioral paradigm to assess the capacity of an auditory drug (cocaine) cue to evoke cocaine-seeking behavior, thus distracting thirsty rats from performing a well-learned sustained attention task (SAT) to obtain a water reward. First, it was determined that an auditory cocaine cue (tone-CS) reinstated drug-seeking equally in sign-trackers (STs) and goal-trackers (GTs), which otherwise vary in the propensity to attribute incentive salience to a localizable drug cue. Next, we tested the ability of an auditory cocaine cue to disrupt performance on the SAT in STs and GTs. Rats were trained to self-administer cocaine intravenously using an Intermittent Access self-administration procedure known to produce a progressive increase in motivation for cocaine, escalation of intake, and strong discriminative stimulus control over drug-seeking behavior. When presented alone, the auditory discriminative stimulus elicited cocaine-seeking behavior while rats were performing the SAT, but it was not sufficiently disruptive to impair SAT performance. In contrast, if cocaine was available in the presence of the cue, or when administered non-contingently, SAT performance was severely disrupted. We suggest that performance on a relatively automatic, stimulus-driven task, such as the basic version of the SAT used here, may be difficult to disrupt with a drug cue alone. A task that requires more top-down cognitive control may be needed. PMID:27890441

NASA's Phonesat Wins 2012 Popular Science Best of What's New Award

NASA Image and Video Library

2012-11-16

Popular Science Magazine has named NASA's PhoneSat project as a winner in the Aerospace category of its 2012 Best of What's New Awards. The awards, now in their 25th year, highlight innovations that once seemed impossible, yet today really exist. Based at NASA Ames Research Center, the goal of the PhoneSat project is to lower the cost of building a space satellite to the point that almost anyone can do so. bout the size of a coffee mug and weighing less than 3 pounds, the total cost of the components for each PhoneSat satellite is about only $3500.

Hot Cell Installation and Demonstration of the Severe Accident Test Station

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

Linton, Kory D.; Burns, Zachary M.; Terrani, Kurt A.

A Severe Accident Test Station (SATS) capable of examining the oxidation kinetics and accident response of irradiated fuel and cladding materials for design basis accident (DBA) and beyond design basis accident (BDBA) scenarios has been successfully installed and demonstrated in the Irradiated Fuels Examination Laboratory (IFEL), a hot cell facility at Oak Ridge National Laboratory. The two test station modules provide various temperature profiles, steam, and the thermal shock conditions necessary for integral loss of coolant accident (LOCA) testing, defueled oxidation quench testing and high temperature BDBA testing. The installation of the SATS system restores the domestic capability to examinemore » postulated and extended LOCA conditions on spent fuel and cladding and provides a platform for evaluation of advanced fuel and accident tolerant fuel (ATF) cladding concepts. This document reports on the successful in-cell demonstration testing of unirradiated Zircaloy-4. It also contains descriptions of the integral test facility capabilities, installation activities, and out-of-cell benchmark testing to calibrate and optimize the system.« less

Small Satellites and the Nigerian National Space Programme

NASA Astrophysics Data System (ADS)

Borroffice, Robert; Chizea, Francis; Sun, Wei; Sweeting, Martin, , Sir

2002-01-01

Space technology and access to space have been elusive to most developing countries over the last half of the 21st century, which is attributed to very low par capital income and the lack of awareness of policy/decision makers about the role of space technology in national development. Space technology was seen as very expensive and prestigious, meant only for the major industrialized countries, while the developing countries should focus on building their national economy and providing food, shelter and other social amenities for their ever-growing populations. In the last decade, the trend has changed with many developing countries embracing spaced technology as one of the major ways of achieving sustainable development. The present trend towards the use of small satellites in meeting national needs has aided this transition because, apart from the small size, they are cheaper to build and to launch, with shorter development time, lower complexity, improved effectiveness and reduced operating costs. This in turn has made them more affordable and has opened up new avenues for the acquisition of satellite technology. The collaborative work between National Space Research and Development Agency of Nigeria (NASRDA) and Surrey Satellite and Technology Limited (SSTL) is a programme aimed at building two small satellites as a way of kick- starting the national space programme. The first project, NigeriaSAT-1, is an enhanced microsatellite carrying Earth observation payloads able to provide 32 metre GSD 3 band multispectral images with a 600km swath width. NigeriaSAT-1 is one of six microsatellites forming the Disaster Monitoring Constellation (DMC) alongside microsatellites contributed by Algeria, China, Turkey, Thailand and UK. Through participation in this international constellation, Nigeria will be able to receive images with a daily revisit worldwide. The EO images generated by NigeriaSAT-1 and the partner microsatellites will be used for providing rapid coverage of natural and man-made disasters but will also be used for monitoring rapidly changing and dynamic aspect of agriculture, the environment, pipeline oil spillages and other national remote sensing requirements. Commercial exploitation of this unique 24hr revisit EO data is planned to offset the government investment. The second national project is NigeriaSAT-2, which is a geostationary communications minisatellite that has been selected specifically to address the lack of communications infrastructure in Nigeria. Both NigeriaSAT-1 and NigeriaSAT-2 projects are being carried out in co-operation with the Surrey Space Centre (UK), combined with a detailed space know-how transfer and training to build up an indigenous Nigeria capability in space technology, EO and communications. While the acquisition and development space technology is the prime focus of the national space programme, an application center, education center and various space research centers are being formed to draw the maximum benefit of space activities for Nigeria. The paper will present the experience of Nigeria in examining the cost/benefit of an affordable space programme based upon small satellites with real applications that will benefit the people of the country. The Nigerian space policy and programme and its first two small satellite projects (NigeriaSAT-1/DMC and NigeriaSAT-2/GEMINI) will also be presented. This paper focuses on how a developing country can take advantage of a cheap and efficient means of gaining access to space and using space technology in achieving its socio-economic development plans.

The Mothership Mission Architecture

NASA Astrophysics Data System (ADS)

Ernst, S. M.; DiCorcia, J. D.; Bonin, G.; Gump, D.; Lewis, J. S.; Foulds, C.; Faber, D.

2015-12-01

The Mothership is considered to be a dedicated deep space carrier spacecraft. It is currently being developed by Deep Space Industries (DSI) as a mission concept that enables a broad participation in the scientific exploration of small bodies - the Mothership mission architecture. A Mothership shall deliver third-party nano-sats, experiments and instruments to Near Earth Asteroids (NEOs), comets or moons. The Mothership service includes delivery of nano-sats, communication to Earth and visuals of the asteroid surface and surrounding area. The Mothership is designed to carry about 10 nano-sats, based upon a variation of the Cubesat standard, with some flexibility on the specific geometry. The Deep Space Nano-Sat reference design is a 14.5 cm cube, which accommodates the same volume as a traditional 3U CubeSat. To reduce cost, Mothership is designed as a secondary payload aboard launches to GTO. DSI is offering slots for nano-sats to individual customers. This enables organizations with relatively low operating budgets to closely examine an asteroid with highly specialized sensors of their own choosing and carry out experiments in the proximity of or on the surface of an asteroid, while the nano-sats can be built or commissioned by a variety of smaller institutions, companies, or agencies. While the overall Mothership mission will have a financial volume somewhere between a European Space Agencies' (ESA) S- and M-class mission for instance, it can be funded through a number of small and individual funding sources and programs, hence avoiding the processes associated with traditional space exploration missions. DSI has been able to identify a significant interest in the planetary science and nano-satellite communities.

The AstroSat Production Line: From AstroSat 100 to AstroSat 1000

NASA Astrophysics Data System (ADS)

Maliet, E.; Pawlak, D.; Koeck, C.; Beaufumé, E.

2008-08-01

From the late 90s onward, Astrium Satellites has developed and improved several classes of high resolution optical Earth Observation satellites. The resulting product line ranges from micro-satellites (about 120 kg) type to the large satellites (in the range of 1 200 kg). They all make uses of state of the art technologies for optical payloads, as well as for avionics. Several classes of platforms have thus been defined and standardised: AstroSat 100 for satellites up to 150 kg, allowing affordable but fully operational missions, AstroSat 500 for satellites up to 800 kg, allowing complex high resolution missions, and AstroSat 1000 for satellites up to 1 200 kg, providing very high resolution and outstanding imaging and agility capabilities. A new class, AstroSat 250, has been developed by Astrium Satellites, and is now proposed, offering a state-of-the-art 3-axis agile platform for high- resolution missions, with a launch mass below 550 kg. The Astrosat platforms rely on a centralised architecture avionics based on an innovative AOCS hybridising of measurements from GPS, stellar sensors and inertial reference unit. Operational safety has been emphasised through thruster free safe modes. All optical payloads make use of all Silicon Carbide (SiC) telescopes. High performance and low consumption linear CCD arrays provide state of the art images. The satellites are designed for simple flight operations, large data collection capability, and large versatility of payload and missions. They are adaptable to a large range of performances. Astrium satellites have already been selected by various customers worldwide.

A Satellite Data Analysis and CubeSat Instrument Simulator Tool for Simultaneous Multi-spacecraft Measurements of Solar Energetic Particles

NASA Astrophysics Data System (ADS)

Vannitsen, Jordan; Rizzitelli, Federico; Wang, Kaiti; Segret, Boris; Juang, Jyh-Ching; Miau, Jiun-Jih

2017-12-01

This paper presents a Multi-satellite Data Analysis and Simulator Tool (MDAST), developed with the original goal to support the science requirements of a Martian 3-Unit CubeSat mission profile named Bleeping Interplanetary Radiation Determination Yo-yo (BIRDY). MDAST was firstly designed and tested by taking into account the positions, attitudes, instruments field of view and energetic particles flux measurements from four spacecrafts (ACE, MSL, STEREO A, and STEREO B). Secondly, the simulated positions, attitudes and instrument field of view from the BIRDY CubeSat have been adapted for input. And finally, this tool can be used for data analysis of the measurements from the four spacecrafts mentioned above so as to simulate the instrument trajectory and observation capabilities of the BIRDY CubeSat. The onset, peak and end time of a solar particle event is specifically defined and identified with this tool. It is not only useful for the BIRDY mission but also for analyzing data from the four satellites aforementioned and can be utilized for other space weather missions with further customization.

Shunt resistance and saturation current determination in CdTe and CIGS solar cells. Part 1: a new theoretical procedure and comparison with other methodologies

NASA Astrophysics Data System (ADS)

Rangel-Kuoppa, Victor-Tapio; Albor-Aguilera, María-de-Lourdes; Hérnandez-Vásquez, César; Flores-Márquez, José-Manuel; González-Trujillo, Miguel-Ángel; Contreras-Puente, Gerardo-Silverio

2018-04-01

A new proposal for the extraction of the shunt resistance (R sh ) and saturation current (I sat ) of a current-voltage (I-V) measurement of a solar cell, within the one-diode model, is given. First, the Cheung method is extended to obtain the series resistance (R s ), the ideality factor (n) and an upper limit for I sat . In this article which is Part 1 of two parts, two procedures are proposed to obtain fitting values for R sh and I sat within some voltage range. These two procedures are used in two simulated I-V curves (one in darkness and the other one under illumination) to recover the known solar cell parameters R sh , R s , n, I sat and the light current I lig and test its accuracy. The method is compared with two different common parameter extraction methods. These three procedures are used and compared in Part 2 in the I-V curves of CdS-CdTe and CIGS-CdS solar cells.

Surgical intervention of pilonidal sinus: impact on patients' postoperative satisfaction and return to work time.

PubMed

Gaiser, Maria Rita; Lee, Sophia Boyoung; Enk, Alexander; Schrott, Peter; Weisser, Heiko

2013-01-01

Pilonidal sinus (PS) is a chronic inflammatory process accompanied by psychological strain and a high rate of work incapacity. To analyze the impact of PS surgery on individual patients' satisfaction (SAT) and economic impacts on work capability. We retrospectively analyzed 40 PS patients regarding SAT and return to work time (RTW) in relation to various factors, using multivariate analysis and Pearson's correlation test. We found a significant negative correlation between SAT and RTW (p<0.01), both correlated equally strongly with duration between first diagnosis and surgery (p<0.01) and with loss of weight (p<0.05). RTW correlated with duration of painkiller intake (p<0.01). SAT correlated with gender (p<0.01), smoking cessation (p<0.05) and quantity of painkiller intake (p<0.01). Satisfaction correlated with gender (p<0.01), smoking cessation (p<0.05), and quantity of painkiller intake (p<0.05). RTW after PS surgery is influenced by factors that can be influenced prior to surgery, leading to better economic results for patients and employers as well as society.

Structural Dynamics and Data Analysis

NASA Technical Reports Server (NTRS)

Luthman, Briana L.

2013-01-01

This project consists of two parts, the first will be the post-flight analysis of data from a Delta IV launch vehicle, and the second will be a Finite Element Analysis of a CubeSat. Shock and vibration data was collected on WGS-5 (Wideband Global SATCOM- 5) which was launched on a Delta IV launch vehicle. Using CAM (CAlculation with Matrices) software, the data is to be plotted into Time History, Shock Response Spectrum, and SPL (Sound Pressure Level) curves. In this format the data is to be reviewed and compared to flight instrumentation data from previous flights of the same launch vehicle. This is done to ensure the current mission environments, such as shock, random vibration, and acoustics, are not out of family with existing flight experience. In family means the peaks on the SRS curve for WGS-5 are similar to the peaks from the previous flights and there are no major outliers. The curves from the data will then be compiled into a useful format so that is can be peer reviewed then presented before an engineering review board if required. Also, the reviewed data will be uploaded to the Engineering Review Board Information System (ERBIS) to archive. The second part of this project is conducting Finite Element Analysis of a CubeSat. In 2010, Merritt Island High School partnered with NASA to design, build and launch a CubeSat. The team is now called StangSat in honor of their mascot, the mustang. Over the past few years, the StangSat team has built a satellite and has now been manifested for flight on a SpaceX Falcon 9 launch in 2014. To prepare for the final launch, a test flight was conducted in Mojave, California. StangSat was launched on a Prospector 18D, a high altitude rocket made by Garvey Spacecraft Corporation, along with their sister satellite CP9 built by California Polytechnic University. However, StangSat was damaged during an off nominal landing and this project will give beneficial insights into what loads the CubeSat experienced during the crash. During the year, the MIHS students generated a SolidWorks (CAD software) geometry model of StangSat. This model will be imported into FEMAP (Finite Element Analysis (FEA) Software) and a finite element model wiiJ be created to predict the loads encountered during the crash of this rocket. This analysis will require learning how to import CAD models into the FEM, mesh and add constraints and concentrated masses to represent components inside the CubeSat frame, such as circuit boards, batteries and accelerometers. During the analysis the loads will be varied, in effort to duplicate the damage to the CubeSat. Results will then be peer reviewed and documented.

Memorial Consequences of Answering SAT II Questions

ERIC Educational Resources Information Center

Marsh, Elizabeth J.; Agarwal, Pooja K.; Roediger, Henry L., III

2009-01-01

Many thousands of students take standardized tests every year. In the current research, we asked whether answering standardized test questions affects students' later test performance. Prior research has shown both positive and negative effects of multiple-choice testing on later tests, with negative effects arising from students selecting…

College Bound Seniors, 1974-75.

ERIC Educational Resources Information Center

College Entrance Examination Board, New York, NY.

Some one million college bound students, who were high school seniors during 1974-75 previously participated in the College Board's Admissions Testing Program (ATP), which included the Scholarship Aptitude Test (SAT), the Test of Standard Written English, the Student Descriptive Questionnaire, and the ATP Achievement Tests. These tests created a…

The SAT's Great Test.

ERIC Educational Resources Information Center

Gose, Ben; Selingo, Jeffrey

2001-01-01

Explores how social, legal, and demographic forces threaten to dethrone the most widely used college entrance exam. New criticism focuses on the use of what is essentially an IQ test to measure students' ability to learn. (EV)

EarthSat spring wheat yield system test 1975, appendix 4

NASA Technical Reports Server (NTRS)

1976-01-01

A computer system is presented which processes meteorological data from both ground observations and meteorologic satellites to define plant weather aspects on a four time per day basis. Plant growth stages are calculated and soil moisture profiles are defined by the system. The EarthSat system assesses plant stress and prepares forecasts of end-of-year yields. The system was used to forecast spring wheat yields in the upper Great Plains states. Hardware and software documentation is provided.

Generalized Nanosatellite Avionics Testbed Lab

NASA Technical Reports Server (NTRS)

Frost, Chad R.; Sorgenfrei, Matthew C.; Nehrenz, Matt

2015-01-01

The Generalized Nanosatellite Avionics Testbed (G-NAT) lab at NASA Ames Research Center provides a flexible, easily accessible platform for developing hardware and software for advanced small spacecraft. A collaboration between the Mission Design Division and the Intelligent Systems Division, the objective of the lab is to provide testing data and general test protocols for advanced sensors, actuators, and processors for CubeSat-class spacecraft. By developing test schemes for advanced components outside of the standard mission lifecycle, the lab is able to help reduce the risk carried by advanced nanosatellite or CubeSat missions. Such missions are often allocated very little time for testing, and too often the test facilities must be custom-built for the needs of the mission at hand. The G-NAT lab helps to eliminate these problems by providing an existing suite of testbeds that combines easily accessible, commercial-offthe- shelf (COTS) processors with a collection of existing sensors and actuators.

Detection of Brucella sp. infection through serological, microbiological, and molecular methods applied to buffaloes in Maranhão State, Brazil.

PubMed

Dos Santos, Larissa Sarmento; Sá, Joicy Cortez; Dos Santos Ribeiro, Diego Luiz; Chaves, Nancyleni Pinto; da Silva Mol, Juliana Pinto; Santos, Renato Lima; da Paixão, Tatiane Alves; de Carvalho Neta, Alcina Vieira

2017-04-01

The aim of the current study is to diagnose Brucella spp. infection using methods such as serology, bacterial isolation, and molecular analysis in buffaloes bred in Maranhão State. In order to do so, 390 samples of buffalo serum were subjected to serological tests, to Rose Bengal Plate Test (RBPT) and to 2-mercaptoethanol (2-ME) combined with slow agglutination test (SAT). Vaginal swabs were collected from seropositive animals and subjected to bacterial isolation and to generic PCR. According to the serological test, 16 animals had a positive reaction to the confirmatory test (2-ME/SAT). As for bacterial isolation, three samples resulted in the isolation of Brucella spp.-characteristic colonies, which were confirmed through PCR. These results confirmed Brucella spp. infection in the buffalo herd from Maranhão State.

Chest Fat Quantification via CT Based on Standardized Anatomy Space in Adult Lung Transplant Candidates

PubMed Central

Tong, Yubing; Udupa, Jayaram K.; Torigian, Drew A.; Odhner, Dewey; Wu, Caiyun; Pednekar, Gargi; Palmer, Scott; Rozenshtein, Anna; Shirk, Melissa A.; Newell, John D.; Porteous, Mary; Diamond, Joshua M.

2017-01-01

Purpose Overweight and underweight conditions are considered relative contraindications to lung transplantation due to their association with excess mortality. Yet, recent work suggests that body mass index (BMI) does not accurately reflect adipose tissue mass in adults with advanced lung diseases. Alternative and more accurate measures of adiposity are needed. Chest fat estimation by routine computed tomography (CT) imaging may therefore be important for identifying high-risk lung transplant candidates. In this paper, an approach to chest fat quantification and quality assessment based on a recently formulated concept of standardized anatomic space (SAS) is presented. The goal of the paper is to seek answers to several key questions related to chest fat quantity and quality assessment based on a single slice CT (whether in the chest, abdomen, or thigh) versus a volumetric CT, which have not been addressed in the literature. Methods Unenhanced chest CT image data sets from 40 adult lung transplant candidates (age 58 ± 12 yrs and BMI 26.4 ± 4.3 kg/m2), 16 with chronic obstructive pulmonary disease (COPD), 16 with idiopathic pulmonary fibrosis (IPF), and the remainder with other conditions were analyzed together with a single slice acquired for each patient at the L5 vertebral level and mid-thigh level. The thoracic body region and the interface between subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) in the chest were consistently defined in all patients and delineated using Live Wire tools. The SAT and VAT components of chest were then segmented guided by this interface. The SAS approach was used to identify the corresponding anatomic slices in each chest CT study, and SAT and VAT areas in each slice as well as their whole volumes were quantified. Similarly, the SAT and VAT components were segmented in the abdomen and thigh slices. Key parameters of the attenuation (Hounsfield unit (HU) distributions) were determined from each chest slice and from the whole chest volume separately for SAT and VAT components. The same parameters were also computed from the single abdominal and thigh slices. The ability of the slice at each anatomic location in the chest (and abdomen and thigh) to act as a marker of the measures derived from the whole chest volume was assessed via Pearson correlation coefficient (PCC) analysis. Results The SAS approach correctly identified slice locations in different subjects in terms of vertebral levels. PCC between chest fat volume and chest slice fat area was maximal at the T8 level for SAT (0.97) and at the T7 level for VAT (0.86), and was modest between chest fat volume and abdominal slice fat area for SAT and VAT (0.73 and 0.75, respectively). However, correlation was weak for chest fat volume and thigh slice fat area for SAT and VAT (0.52 and 0.37, respectively), and for chest fat volume for SAT and VAT and BMI (0.65 and 0.28, respectively). These same single slice locations with maximal PCC were found for SAT and VAT within both COPD and IPF groups. Most of the attenuation properties derived from the whole chest volume and single best chest slice for VAT (but not for SAT) were significantly different between COPD and IPF groups. Conclusions This study demonstrates a new way of optimally selecting slices whose measurements may be used as markers of similar measurements made on the whole chest volume. The results suggest that one or two slices imaged at T7 and T8 vertebral levels may be enough to estimate reliably the total SAT and VAT components of chest fat and the quality of chest fat as determined by attenuation distributions in the entire chest volume. PMID:28046024

Chest Fat Quantification via CT Based on Standardized Anatomy Space in Adult Lung Transplant Candidates.

PubMed

Tong, Yubing; Udupa, Jayaram K; Torigian, Drew A; Odhner, Dewey; Wu, Caiyun; Pednekar, Gargi; Palmer, Scott; Rozenshtein, Anna; Shirk, Melissa A; Newell, John D; Porteous, Mary; Diamond, Joshua M; Christie, Jason D; Lederer, David J

2017-01-01

Overweight and underweight conditions are considered relative contraindications to lung transplantation due to their association with excess mortality. Yet, recent work suggests that body mass index (BMI) does not accurately reflect adipose tissue mass in adults with advanced lung diseases. Alternative and more accurate measures of adiposity are needed. Chest fat estimation by routine computed tomography (CT) imaging may therefore be important for identifying high-risk lung transplant candidates. In this paper, an approach to chest fat quantification and quality assessment based on a recently formulated concept of standardized anatomic space (SAS) is presented. The goal of the paper is to seek answers to several key questions related to chest fat quantity and quality assessment based on a single slice CT (whether in the chest, abdomen, or thigh) versus a volumetric CT, which have not been addressed in the literature. Unenhanced chest CT image data sets from 40 adult lung transplant candidates (age 58 ± 12 yrs and BMI 26.4 ± 4.3 kg/m2), 16 with chronic obstructive pulmonary disease (COPD), 16 with idiopathic pulmonary fibrosis (IPF), and the remainder with other conditions were analyzed together with a single slice acquired for each patient at the L5 vertebral level and mid-thigh level. The thoracic body region and the interface between subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) in the chest were consistently defined in all patients and delineated using Live Wire tools. The SAT and VAT components of chest were then segmented guided by this interface. The SAS approach was used to identify the corresponding anatomic slices in each chest CT study, and SAT and VAT areas in each slice as well as their whole volumes were quantified. Similarly, the SAT and VAT components were segmented in the abdomen and thigh slices. Key parameters of the attenuation (Hounsfield unit (HU) distributions) were determined from each chest slice and from the whole chest volume separately for SAT and VAT components. The same parameters were also computed from the single abdominal and thigh slices. The ability of the slice at each anatomic location in the chest (and abdomen and thigh) to act as a marker of the measures derived from the whole chest volume was assessed via Pearson correlation coefficient (PCC) analysis. The SAS approach correctly identified slice locations in different subjects in terms of vertebral levels. PCC between chest fat volume and chest slice fat area was maximal at the T8 level for SAT (0.97) and at the T7 level for VAT (0.86), and was modest between chest fat volume and abdominal slice fat area for SAT and VAT (0.73 and 0.75, respectively). However, correlation was weak for chest fat volume and thigh slice fat area for SAT and VAT (0.52 and 0.37, respectively), and for chest fat volume for SAT and VAT and BMI (0.65 and 0.28, respectively). These same single slice locations with maximal PCC were found for SAT and VAT within both COPD and IPF groups. Most of the attenuation properties derived from the whole chest volume and single best chest slice for VAT (but not for SAT) were significantly different between COPD and IPF groups. This study demonstrates a new way of optimally selecting slices whose measurements may be used as markers of similar measurements made on the whole chest volume. The results suggest that one or two slices imaged at T7 and T8 vertebral levels may be enough to estimate reliably the total SAT and VAT components of chest fat and the quality of chest fat as determined by attenuation distributions in the entire chest volume.

A data assimilation system combining CryoSat-2 data and hydrodynamic river models

NASA Astrophysics Data System (ADS)

Schneider, Raphael; Ridler, Marc-Etienne; Godiksen, Peter Nygaard; Madsen, Henrik; Bauer-Gottwein, Peter

2018-02-01

There are numerous hydrologic studies using satellite altimetry data from repeat-orbit missions such as Envisat or Jason over rivers. This study is one of the first examples for the combination of altimetry from drifting-ground track satellite missions, namely CryoSat-2, with a river model. CryoSat-2 SARIn Level 2 data is used to improve a 1D hydrodynamic model of the Brahmaputra River in South Asia, which is based on the Saint-Venant equations for unsteady flow and set up in the MIKE HYDRO River software. After calibration of discharge and water level the hydrodynamic model can accurately and bias-free represent the spatio-temporal variations of water levels. A data assimilation framework has been developed and linked with the model. It is a flexible framework that can assimilate water level data which are arbitrarily distributed in time and space. The setup has been used to assimilate CryoSat-2 water level observations over the Assam valley for the years 2010-2015, using an Ensemble Transform Kalman Filter (ETKF). Performance improvement in terms of discharge forecasting skill was then evaluated. For experiments with synthetic CryoSat-2 data the continuous ranked probability score (CRPS) was improved by up to 32%, whilst for experiments assimilating real data it could be improved by up to 10%. The developed methods are expected to be transferable to other rivers and altimeter missions. The model setup and calibration is based almost entirely on globally available remote sensing data.

Postembryonic lineages of the Drosophila brain: I. Development of the lineage-associated fiber tracts.

PubMed

Lovick, Jennifer K; Ngo, Kathy T; Omoto, Jaison J; Wong, Darren C; Nguyen, Joseph D; Hartenstein, Volker

2013-12-15

Neurons of the Drosophila central brain fall into approximately 100 paired groups, termed lineages. Each lineage is derived from a single asymmetrically-dividing neuroblast. Embryonic neuroblasts produce 1,500 primary neurons (per hemisphere) that make up the larval CNS followed by a second mitotic period in the larva that generates approximately 10,000 secondary, adult-specific neurons. Clonal analyses based on previous works using lineage-specific Gal4 drivers have established that such lineages form highly invariant morphological units. All neurons of a lineage project as one or a few axon tracts (secondary axon tracts, SATs) with characteristic trajectories, thereby representing unique hallmarks. In the neuropil, SATs assemble into larger fiber bundles (fascicles) which interconnect different neuropil compartments. We have analyzed the SATs and fascicles formed by lineages during larval, pupal, and adult stages using antibodies against membrane molecules (Neurotactin/Neuroglian) and synaptic proteins (Bruchpilot/N-Cadherin). The use of these markers allows one to identify fiber bundles of the adult brain and associate them with SATs and fascicles of the larval brain. This work lays the foundation for assigning the lineage identity of GFP-labeled MARCM clones on the basis of their close association with specific SATs and neuropil fascicles, as described in the accompanying paper (Wong et al., 2013. Postembryonic lineages of the Drosophila brain: II. Identification of lineage projection patterns based on MARCM clones. Submitted.). Copyright © 2013 Elsevier Inc. All rights reserved.

MarCO and Dispenser

NASA Image and Video Library

2018-04-19

One of the MarCO CubeSats inside a cleanroom at Cal Poly San Luis Obispo, before being placed into its deployment box. The deployment box will eject the briefcase-sized CubeSat into space after launch. It and its twin will accompany the InSight Mars lander when it lifts off from Vandenberg Air Force Base in May. https://photojournal.jpl.nasa.gov/catalog/PIA22322

Are the Best Scores the Best Scores for Predicting College Success?

ERIC Educational Resources Information Center

Patterson, Brian F.; Mattern, Krista D.; Swerdzewski, Peter

2012-01-01

The College Board's SAT[R] Score Choice[TM] policy allows students to choose which set(s) of scores to send to colleges and universities to which they plan to apply. Based on data gathered before the implementation of that policy, the following study evaluated the predictive validity of the various sets of SAT scores. The value of five score sets…

Evaluation of Multilayer Cloud Detection Using a MODIS CO2-Slicing Algorithm With CALIPSO-CloudSat Measurements

NASA Technical Reports Server (NTRS)

Viudez-Mora, Antonio; Kato, Seiji

2015-01-01

This work evaluates the multilayer cloud (MCF) algorithm based on CO2-slicing techniques against CALISPO-CloudSat (CLCS) measurement. This evaluation showed that the MCF underestimates the presence of multilayered clouds compared with CLCS and are retrained to cloud emissivities below 0.8 and cloud optical septs no larger than 0.3.

SkySat-1: very high-resolution imagery from a small satellite

NASA Astrophysics Data System (ADS)

Murthy, Kiran; Shearn, Michael; Smiley, Byron D.; Chau, Alexandra H.; Levine, Josh; Robinson, M. Dirk

2014-10-01

This paper presents details of the SkySat-1 mission, which is the first microsatellite-class commercial earth- observation system to generate sub-meter resolution panchromatic imagery, in addition to sub-meter resolution 4-band pan-sharpened imagery. SkySat-1 was built and launched for an order of magnitude lower cost than similarly performing missions. The low-cost design enables the deployment of a large imaging constellation that can provide imagery with both high temporal resolution and high spatial resolution. One key enabler of the SkySat-1 mission was simplifying the spacecraft design and instead relying on ground- based image processing to achieve high-performance at the system level. The imaging instrument consists of a custom-designed high-quality optical telescope and commercially-available high frame rate CMOS image sen- sors. While each individually captured raw image frame shows moderate quality, ground-based image processing algorithms improve the raw data by combining data from multiple frames to boost image signal-to-noise ratio (SNR) and decrease the ground sample distance (GSD) in a process Skybox calls "digital TDI". Careful qual-ity assessment and tuning of the spacecraft, payload, and algorithms was necessary to generate high-quality panchromatic, multispectral, and pan-sharpened imagery. Furthermore, the framing sensor configuration en- abled the first commercial High-Definition full-frame rate panchromatic video to be captured from space, with approximately 1 meter ground sample distance. Details of the SkySat-1 imaging instrument and ground-based image processing system are presented, as well as an overview of the work involved with calibrating and validating the system. Examples of raw and processed imagery are shown, and the raw imagery is compared to pre-launch simulated imagery used to tune the image processing algorithms.

Autonomous Sensors for Large Scale Data Collection

NASA Astrophysics Data System (ADS)

Noto, J.; Kerr, R.; Riccobono, J.; Kapali, S.; Migliozzi, M. A.; Goenka, C.

2017-12-01

Presented here is a novel implementation of a "Doppler imager" which remotely measures winds and temperatures of the neutral background atmosphere at ionospheric altitudes of 87-300Km and possibly above. Incorporating both recent optical manufacturing developments, modern network awareness and the application of machine learning techniques for intelligent self-monitoring and data classification. This system achieves cost savings in manufacturing, deployment and lifetime operating costs. Deployed in both ground and space-based modalities, this cost-disruptive technology will allow computer models of, ionospheric variability and other space weather models to operate with higher precision. Other sensors can be folded into the data collection and analysis architecture easily creating autonomous virtual observatories. A prototype version of this sensor has recently been deployed in Trivandrum India for the Indian Government. This Doppler imager is capable of operation, even within the restricted CubeSat environment. The CubeSat bus offers a very challenging environment, even for small instruments. The lack of SWaP and the challenging thermal environment demand development of a new generation of instruments; the Doppler imager presented is well suited to this environment. Concurrent with this CubeSat development is the development and construction of ground based arrays of inexpensive sensors using the proposed technology. This instrument could be flown inexpensively on one or more CubeSats to provide valuable data to space weather forecasters and ionospheric scientists. Arrays of magnetometers have been deployed for the last 20 years [Alabi, 2005]. Other examples of ground based arrays include an array of white-light all sky imagers (THEMIS) deployed across Canada [Donovan et al., 2006], oceans sensors on buoys [McPhaden et al., 2010], and arrays of seismic sensors [Schweitzer et al., 2002]. A comparable array of Doppler imagers can be constructed and deployed on the ground, to compliment the CubeSat data.

Climatic warming in China during 1901–2015 based on an extended dataset of instrumental temperature records

DOE PAGES

Cao, Lijuan; Yan, Zhongwei; Zhao, Ping; ...

2017-05-26

Monthly mean instrumental surface air temperature (SAT) observations back to the nineteenth century in China are synthesized from different sources via specific quality-control, interpolation, and homogenization. Compared with the first homogenized long-term SAT dataset for China which contained 18 stations mainly located in the middle and eastern part of China, the present dataset includes homogenized monthly SAT series at 32 stations, with an extended coverage especially towards western China. Missing values are interpolated by using observations at nearby stations, including those from neighboring countries. Cross validation shows that the mean bias error (MBE) is generally small and falls between 0.45more » °C and –0.35 °C. Multiple homogenization methods and available metadata are applied to assess the consistency of the time series and to adjust inhomogeneity biases. The homogenized annual mean SAT series shows a range of trends between 1.1 °C and 4.0 °C/century in northeastern China, between 0.4 °C and 1.9 °C/century in southeastern China, and between 1.4 °C and 3.7 °C/century in western China to the west of 105 E (from the initial years of the stations to 2015). The unadjusted data include unusually warm records during the 1940s and hence tend to underestimate the warming trends at a number of stations. As a result, the mean SAT series for China based on the climate anomaly method shows a warming trend of 1.56 °C/century during 1901–2015, larger than those based on other currently available datasets.« less

Climatic warming in China during 1901–2015 based on an extended dataset of instrumental temperature records

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

Cao, Lijuan; Yan, Zhongwei; Zhao, Ping

Monthly mean instrumental surface air temperature (SAT) observations back to the nineteenth century in China are synthesized from different sources via specific quality-control, interpolation, and homogenization. Compared with the first homogenized long-term SAT dataset for China which contained 18 stations mainly located in the middle and eastern part of China, the present dataset includes homogenized monthly SAT series at 32 stations, with an extended coverage especially towards western China. Missing values are interpolated by using observations at nearby stations, including those from neighboring countries. Cross validation shows that the mean bias error (MBE) is generally small and falls between 0.45more » °C and –0.35 °C. Multiple homogenization methods and available metadata are applied to assess the consistency of the time series and to adjust inhomogeneity biases. The homogenized annual mean SAT series shows a range of trends between 1.1 °C and 4.0 °C/century in northeastern China, between 0.4 °C and 1.9 °C/century in southeastern China, and between 1.4 °C and 3.7 °C/century in western China to the west of 105 E (from the initial years of the stations to 2015). The unadjusted data include unusually warm records during the 1940s and hence tend to underestimate the warming trends at a number of stations. As a result, the mean SAT series for China based on the climate anomaly method shows a warming trend of 1.56 °C/century during 1901–2015, larger than those based on other currently available datasets.« less

VANDENBERG AIR FORCE BASE, CALIF. - Workers mate the Pegasus , with its cargo of the SciSat-1 payload to the L-1011 carrier aircraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-08-09

VANDENBERG AIR FORCE BASE, CALIF. - Workers mate the Pegasus , with its cargo of the SciSat-1 payload to the L-1011 carrier aircraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

VANDENBERG AIR FORCE BASE, CALIF. - At Vandenberg AFB, Calif., a solar array is installed on the SciSat-1 spacecraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-07-29

VANDENBERG AIR FORCE BASE, CALIF. - At Vandenberg AFB, Calif., a solar array is installed on the SciSat-1 spacecraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

VANDENBERG AIR FORCE BASE, CALIF. - The SciSat-1 payload and Pegasus launch vehicle are lifted and mated to the L-1011 carrier aircraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

NASA Image and Video Library

2003-08-09

VANDENBERG AIR FORCE BASE, CALIF. - The SciSat-1 payload and Pegasus launch vehicle are lifted and mated to the L-1011 carrier aircraft. The SciSat-1 weighs approximately 330 pounds and after launch will be placed in a 400-mile-high polar orbit to investigate processes that control the distribution of ozone in the upper atmosphere. The data from the satellite will provide Canadian and international scientists with improved measurements relating to global ozone processes and help policymakers assess existing environmental policy and develop protective measures for improving the health of our atmosphere, preventing further ozone depletion. The mission is designed to last two years.

W-band spaceborne radar observations of atmospheric river events

NASA Astrophysics Data System (ADS)

Matrosov, S. Y.

2010-12-01

While the main objective of the world first W-band radar aboard the CloudSat satellite is to provide vertically resolved information on clouds, it proved to be a valuable tool for observing precipitation. The CloudSat radar is generally able to resolve precipitating cloud systems in their vertical entirety. Although measurements from the liquid hydrometer layer containing rainfall are strongly attenuated, special retrieval approaches can be used to estimate rainfall parameters. These approaches are based on vertical gradients of observed radar reflectivity factor rather than on absolute estimates of reflectivity. Concurrent independent estimations of ice cloud parameters in the same vertical column allow characterization of precipitating systems and provide information on coupling between clouds and rainfall they produce. The potential of CloudSat for observations atmospheric river events affecting the West Coast of North America is evaluated. It is shown that spaceborne radar measurements can provide high resolution information on the height of the freezing level thus separating areas of rainfall and snowfall. CloudSat precipitation rate estimates complement information from the surface-based radars. Observations of atmospheric rivers at different locations above the ocean and during landfall help to understand evolutions of atmospheric rivers and their structures.

Using Additive Manufacturing to Print a CubeSat Propulsion System

NASA Technical Reports Server (NTRS)

Marshall, William M.; Zemba, Michael; Shemelya, Corey; Wicker, Ryan; Espalin, David; MacDonald, Eric; Keif, Craig; Kwas, Andrew

2015-01-01

Small satellites, such as CubeSats, are increasingly being called upon to perform missions traditionally ascribed to larger satellite systems. However, the market of components and hardware for small satellites, particularly CubeSats, still falls short of providing the necessary capabilities required by ever increasing mission demands. One way to overcome this shortfall is to develop the ability to customize every build. By utilizing fabrication methods such as additive manufacturing, mission specific capabilities can be built into a system, or into the structure, that commercial off-the-shelf components may not be able to provide. A partnership between the University of Texas at El Paso, COSMIAC at the University of New Mexico, Northrop Grumman, and the NASA Glenn Research Center is looking into using additive manufacturing techniques to build a complete CubeSat, under the Small Spacecraft Technology Program. The W. M. Keck Center at the University of Texas at El Paso has previously demonstrated the ability to embed electronics and wires into the addtively manufactured structures. Using this technique, features such as antennas and propulsion systems can be included into the CubeSat structural body. Of interest to this paper, the team is investigating the ability to take a commercial micro pulsed plasma thruster and embed it into the printing process. Tests demonstrating the dielectric strength of the printed material and proof-of-concept demonstration of the printed thruster will be shown.

Neural chronometry and coherency across speed-accuracy demands reveal lack of homomorphism between computational and neural mechanisms of evidence accumulation.

PubMed

Heitz, Richard P; Schall, Jeffrey D

2013-10-19

The stochastic accumulation framework provides a mechanistic, quantitative account of perceptual decision-making and how task performance changes with experimental manipulations. Importantly, it provides an elegant account of the speed-accuracy trade-off (SAT), which has long been the litmus test for decision models, and also mimics the activity of single neurons in several key respects. Recently, we developed a paradigm whereby macaque monkeys trade speed for accuracy on cue during visual search task. Single-unit activity in frontal eye field (FEF) was not homomorphic with the architecture of models, demonstrating that stochastic accumulators are an incomplete description of neural activity under SAT. This paper summarizes and extends this work, further demonstrating that the SAT leads to extensive, widespread changes in brain activity never before predicted. We will begin by reviewing our recently published work that establishes how spiking activity in FEF accomplishes SAT. Next, we provide two important extensions of this work. First, we report a new chronometric analysis suggesting that increases in perceptual gain with speed stress are evident in FEF synaptic input, implicating afferent sensory-processing sources. Second, we report a new analysis demonstrating selective influence of SAT on frequency coupling between FEF neurons and local field potentials. None of these observations correspond to the mechanics of current accumulator models.

Engineering a responsive, low cost, tactical satellite, TACSAT-1

NASA Astrophysics Data System (ADS)

Hurley, M.; Duffey, T.; Huffine, Christopher; Weldy, Ken; Clevland, Jeff; Hauser, Joe

2004-11-01

The Secretary of Defense's Office of Force Transformation (OFT) is currently undertaking an initiative to develop a low-cost, responsive, operationally relevant space capability using small satellites. The Naval Research Laboratory (NRL) is tasked to be program manger for this initiative, which seeks to make space assets and capabilities available to operational users. TacSat-1 is the first in a series of small satellites that will result in rapid, tailored, and operationally relevant experimental space capabilities for tactical forces. Components of the resulting tactical architecture include a highly automated small satellite bus, modular payloads, common launch and payload interfaces, tasking and data dissemination using the SIPRNET (Secret Internet Protocol Routing Network), and low cost, rapid response launches. The overall goal of TacSat-1 is to demonstrate the utility of a broader complementary business model and provide a catalyst for energizing DoD and industry in the operational space area. This paper first provides a brief overview of the TacSat- 1 experiment and then discusses the engineering designs and practices used to achieve the aggressive cost and schedule goals. Non-standard approaches and engineering philosophies that allowed the TacSat-1 spacecraft to be finished in twelve months are detailed and compared with "normal" satellite programs where applicable. Specific subsystem design, integration and test techniques, which contributed to the successful completion of the TacSat-1 spacecraft, are reviewed. Finally, lessons learned are discussed.

NEUDOSE: A CubeSat Mission for Dosimetry of Charged Particles and Neutrons in Low-Earth Orbit.

PubMed

Hanu, A R; Barberiz, J; Bonneville, D; Byun, S H; Chen, L; Ciambella, C; Dao, E; Deshpande, V; Garnett, R; Hunter, S D; Jhirad, A; Johnston, E M; Kordic, M; Kurnell, M; Lopera, L; McFadden, M; Melnichuk, A; Nguyen, J; Otto, A; Scott, R; Wagner, D L; Wiendels, M

2017-01-01

During space missions, astronauts are exposed to a stream of energetic and highly ionizing radiation particles that can suppress immune system function, increase cancer risks and even induce acute radiation syndrome if the exposure is large enough. As human exploration goals shift from missions in low-Earth orbit (LEO) to long-duration interplanetary missions, radiation protection remains one of the key technological issues that must be resolved. In this work, we introduce the NEUtron DOSimetry & Exploration (NEUDOSE) CubeSat mission, which will provide new measurements of dose and space radiation quality factors to improve the accuracy of cancer risk projections for current and future space missions. The primary objective of the NEUDOSE CubeSat is to map the in situ lineal energy spectra produced by charged particles and neutrons in LEO where most of the preparatory activities for future interplanetary missions are currently taking place. To perform these measurements, the NEUDOSE CubeSat is equipped with the Charged & Neutral Particle Tissue Equivalent Proportional Counter (CNP-TEPC), an advanced radiation monitoring instrument that uses active coincidence techniques to separate the interactions of charged particles and neutrons in real time. The NEUDOSE CubeSat, currently under development at McMaster University, provides a modern approach to test the CNP-TEPC instrument directly in the unique environment of outer space while simultaneously collecting new georeferenced lineal energy spectra of the radiation environment in LEO.

Improved Orbit Determination of LEO CubeSats: Project LEDsat

NASA Astrophysics Data System (ADS)

Cutler, J.; Seitzer, P.; Lee, C. H.; Washabaugh, P.; Sharma, S.; Gitten, R.; Piergentili, F.; Santoni, F.; Cardona, T.; Cialone, G.; Frezza, L.; Gianfermo, A.; Marzioli, P.; Masillo, S.; Pellegrino, A.; Schildknecht, T.; Bedard, D.; Cowardin, H.

Project LEDsat is an international project (USA, Italy, and Canada) designed to improve the identification and orbit determination of CubeSats in low Earth orbit (LEO). The goal is to fly CubeSats with multiple methods of measuring positions on the same spacecraft: GPS, optical tracking, satellite laser ranging (SLR), and radio tracking. These satellites will be equipped with light emitting diodes (LEDs) for optical tracking while the satellite is in Earth shadow. It will be possible to compare the orbits determined from different methods to examine the systematic and random errors associated with each method. Furthermore, if each LEDsat has a different flash pattern, then it will be possible to distinguish closely spaced satellites shortly after deployment. The Sapienza University of Rome 3U CubeSat URSA MAIOR with LEDs and retro-reflectors was launched in June 2017 and is working on orbit. Sapienza has designed a 1U CubeSat follow-on mission dedicated to LED tracking, which was selected for possible launch in 2018 in the European Space Agency's (ESA) 'Fly Your Satellite' program. The University of Michigan is designing a 3U version with LEDs, GPS receiver, SLR, and radio tracking. The Royal Military College of Canada (RMC) is leading a Canadian effort for a LEDsat mission as well. All three organizations have a program of testing LEDs for space use to predict the effects of the LEO space environment.

Expression of Innate Immune Response Genes in Liver and Three Types of Adipose Tissue in Cloned Pigs

PubMed Central

Rødgaard, Tina; Skovgaard, Kerstin; Stagsted, Jan

2012-01-01

Abstract The pig has been proposed as a relevant model for human obesity-induced inflammation, and cloning may improve the applicability of this model. We tested the assumptions that cloning would reduce interindividual variation in gene expression of innate immune factors and that their expression would remain unaffected by the cloning process. We investigated the expression of 40 innate immune factors by high-throughput quantitative real-time PCR in samples from liver, abdominal subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), and neck SAT in cloned pigs compared to normal outbred pigs. The variation in gene expression was found to be similar for the two groups, and the expression of a small number of genes was significantly affected by cloning. In the VAT and abdominal SAT, six out of seven significantly differentially expressed genes were downregulated in the clones. In contrast, most differently expressed genes in both liver and neck SAT were upregulated (seven out of eight). Remarkably, acute phase proteins (APPs) dominated the upregulated genes in the liver, whereas APP expression was either unchanged or downregulated in abdominal SAT and VAT. The general conclusion from this work is that cloning leads to subtle changes in specific subsets of innate immune genes. Such changes, even if minor, may have phenotypic effects over time, e.g., in models of long-term inflammation related to obesity. PMID:22928970

EarthSat spring wheat yield system test 1975

NASA Technical Reports Server (NTRS)

1976-01-01

The results of an operational test of the EarthSat System during the period 1 June - 30 August 1975 over the spring wheat regions of North Dakota, South Dakota, and Minnesota are presented. The errors associated with each sub-element of the system during the operational test and the sensitivity of the complete system and each major functional sub-element of the system to the observed errors were evaluated. Evaluations and recommendations for future operational users of the system include: (1) changes in various system sub-elements, (2) changes in the yield model to affect improved accuracy, (3) changes in the number of geobased cells needed to develop an accurate aggregated yield estimate, (4) changes associated with the implementation of future operational satellites and data processing systems, and (5) detailed system documentation.

Fine Ice Sheet margins topography from swath processing of CryoSat SARIn mode data

NASA Astrophysics Data System (ADS)

Gourmelen, N.; Escorihuela, M. J.; Shepherd, A.; Foresta, L.; Muir, A.; Briggs, K.; Hogg, A. E.; Roca, M.; Baker, S.; Drinkwater, M. R.

2014-12-01

Reference and repeat-observations of Glacier and Ice Sheet Margin (GISM) topography are critical to identify changes in ice thickness, provide estimates of mass gain or loss and thus quantify the contribution of the cryosphere to sea level change. The lack of such sustained observations was identified in the Integrated Global Observing Strategy (IGOS) Cryosphere Theme Report as a major shortcoming. Conventional altimetry measurements over GISMs exist, but coverage has been sparse and characterized by coarse ground resolution. Additionally, and more importantly, they proved ineffective in the presence of steep slopes, a typical feature of GISM areas. Since the majority of Antarctic and Greenland ice sheet mass loss is estimated to lie within 100 km from the coast, but only about 10% is surveyed, there is the need for more robust and dense observations of GISMs, in both time and space. The ESA Altimetry mission CryoSat aims at gaining better insight into the evolution of the Cryosphere. CryoSat's revolutionary design features a Synthetic Interferometric Radar Altimeter (SIRAL), with two antennas for interferometry. The corresponding SAR Interferometer (SARIn) mode of operation increases spatial resolution while resolving the angular origin of off-nadir echoes occurring over sloping terrain. The SARIn mode is activated over GISMs and the elevation for the Point Of Closest Approach (POCA) is a standard product of the CryoSat mission. Here we present an approach for more comprehensively exploiting the SARIn mode of CryoSat and produce an ice elevation product with enhanced spatial resolution compared to standard CryoSat-2 height products. In this so called L2-swath processing approach, the full CryoSat waveform is exploited under specific conditions of signal and surface characteristics. We will present the rationale, validation exercises and preliminary results from the Eurpean Space Agency's STSE CryoTop study over selected test regions of the margins of the Greenland and Antarctic Ice Sheets.

MarCOs Cruise in Deep Space

NASA Image and Video Library

2018-03-29

An artist's rendering of the twin Mars Cube One (MarCO) spacecraft as they fly through deep space. The MarCOs will be the first CubeSats -- a kind of modular, mini-satellite -- attempting to fly to another planet. They're designed to fly along behind NASA's InSight lander on its cruise to Mars. If they make the journey, they will test a relay of data about InSight's entry, descent and landing back to Earth. Though InSight's mission will not depend on the success of the MarCOs, they will be a test of how CubeSats can be used in deep space. https://photojournal.jpl.nasa.gov/catalog/PIA22314

Distant Perspective of MarCOs Cruise in Deep Space

NASA Image and Video Library

2018-03-29

An artist's rendering of the twin Mars Cube One (MarCO) spacecraft on their cruise in deep space. The MarCOs will be the first CubeSats -- a kind of modular, mini-satellite -- attempting to fly to another planet. They're designed to fly along behind NASA's InSight lander on its cruise to Mars. If they make the journey, they will test a relay of data about InSight's entry, descent and landing back to Earth. Though InSight's mission will not depend on the success of the MarCOs, they will be a test of how CubeSats can be used in deep space. https://photojournal.jpl.nasa.gov/catalog/PIA22315

Constellation of CubeSats for Realtime Ionospheric E-field Measurements for Global Space Weather

NASA Astrophysics Data System (ADS)

Crowley, G.; Swenson, C.; Pilinski, M.; Fish, C. S.; Neilsen, T. L.; Stromberg, E. M.; Azeem, I.; Barjatya, A.

2014-12-01

Inexpensive and robust space-weather monitoring instruments are needed to fill upcoming gaps in the Nation's ability to meet requirements for space weather specification and forecasting. Foremost among the needed data are electric fields, since they drive global ionospheric and thermospheric behavior, and because there are relatively few ground-based measurements. We envisage a constellation of CubeSats to provide global coverage of the electric field and its variability. The DICE (Dynamic Ionosphere CubeSat Experiment) mission was a step towards this goal, with two identical 1.5U CubeSats, each carrying three space weather instruments: (1) double probe instruments to measure AC and DC electric fields; (2) Langmuir probes to measure ionospheric electron density, and; (3) a magnetometer to measure field-aligned currents. DICE launched in October 2011. DICE was the first CubeSat mission to observe a Storm Enhanced Density event, fulfilling a major goal of the mission. Due to attitude control anomalies encountered in orbit, the DICE electric field booms have not yet been deployed. Important lessons have been learned for the implementation of a spin-stabilized CubeSat, and the design and performance of the Attitude Determination & Control System (ADCS). These lessons are now being applied to the DIME SensorSat, a risk-reduction mission that is capable of deploying flexible electric field booms up to a distance of 10-m tip-to-tip from a 1.5U CubeSat. DIME will measure AC and DC electric fields, and will exceed several IORD-2 threshold requirements. Ion densities, and magnetic fields will also be measured to characterize the performance of the sensor in different plasma environments. We show the utility of a constellation of electric field measurements, describe the DIME SensorSat, and demonstrate how the measurement will meet or exceed IORD requirements. The reduced cost of these sensors will enable constellations that can, for the first time, adequately resolve the spatial and temporal variability in ionospheric electrodynamics. DICE and DIME are collaborations between ASTRA and Space Dynamics Lab/Utah State University.

Propulsion System Testing for the Iodine Satellite (iSAT) Demonstration Mission

NASA Technical Reports Server (NTRS)

Polzin, Kurt A.; Kamhawi, Hani

2015-01-01

CUBESATS are relatively new spacecraft platforms that are typically deployed from a launch vehicle as a secondary payload, providing low-cost access to space for a wide range of end-users. These satellites are comprised of building blocks having dimensions of 10x10x10 cm cu and a mass of 1.33 kg (a 1-U size). While providing low-cost access to space, a major operational limitation is the lack of a propulsion system that can fit within a CubeSat and is capable of executing high delta v maneuvers. This makes it difficult to use CubeSats on missions requiring certain types of maneuvers (i.e. formation flying, spacecraft rendezvous). Recently, work has been performed investigating the use of iodine as a propellant for Hall-effect thrusters (HETs) 2 that could subsequently be used to provide a high specific impulse path to CubeSat propulsion. 3, 4 Iodine stores as a dense solid at very low pressures, making it acceptable as a propellant on a secondary payload. It has exceptionally high ?Isp (density times specific impulse), making it an enabling technology for small satellite near-term applications and providing the potential for systems-level advantages over mid-term high power electric propulsion options. Iodine flow can also be thermally regulated, subliming at relatively low temperature (less than 100 C) to yield I2 vapor at or below 50 torr. At low power, the measured performance of an iodine-fed HET is very similar to that of a state-of-the-art xenon-fed thruster. Just as importantly, the current-voltage discharge characteristics of low power iodine-fed and xenon-fed thrusters are remarkably similar, potentially reducing development and qualifications costs by making it possible to use an already-qualified xenon-HET PPU in an iodine-fed system. Finally, a cold surface can be installed in a vacuum test chamber on which expended iodine propellant can deposit. In addition, the temperature doesn't have to be extremely cold to maintain a low vapor pressure in the vacuum chamber (it is under 10(exp -6) torr at -75 C), making it possible to 'cryopump' the propellant with lower-cost recirculating refrigerant-based systems as opposed to using liquid nitrogen or low temperature gaseous helium cryopanels. An iodine-based system is not without its challenges. The primary challenge is that the entire feed system must be maintained at an elevated temperature to prevent the iodine from depositing (transitioning from the gas phase directly back into the solid phase), which will block the propellant feed lines. Furthermore, deposition will occur unless the temperature in the lines is not greater than the temperature of the propellant reservoir. The flow rate can be controlled by adjusting the heating applied to the reservoir, but as with any thermal control there is a relatively slow response to changes in the heating rate. In the present paper, we describe the propulsion and propellant feed system for the iodine satellite (iSAT) flight demonstration mission. The system is based around the Busek BHT-200 Hall thruster, which has been modified for chemical compatibility with iodine vapor. While the gross propellant flow rate is maintained by the heated propellant reservoir, the flow to the anode and cathode are adjusted using two heated Vacco proportional flow control valves (PFCV), which provide very fast response on the flow rate adjustment. The flight mission design layout will be presented, showing how the system will be packaged into the overall 12-U spacecraft and the techniques being employed to protect the remaining spacecraft hardware from the propulsion system (e.g., plasma impingement, iodine deposition, thermal loads). In addition to the flight system design, results of testing the thruster and cathode with both operating on iodine propellant are presented. The tests are conducted on a thrust stand (see Fig. 1) in a large vacuum chamber containing a beam dump chilled to below -100 C to 'cryopump' the propellant. The thruster performance during these tests is presented, with these data used to evaluate the feed system and guide further refinements. Results of relatively long duration testing are presented to demonstrate the capability to operate for the length of the iSAT mission and to perform a number of re-starts as will be required by the mission concept of operations.

Manipulation of oligonucleotides immobilized on solid supports - DNA computations on surfaces

NASA Astrophysics Data System (ADS)

Liu, Qinghua

The manipulation of DNA oligonucleotides immobilized on various solid supports has been studied intensively, especially in the area of surface hybridization. Recently, surface-based biotechnology has been applied to the area of molecular computing. These surface-based methods have advantages with regard to ease of handling, facile purification, and less interference when compared to solution methodologies. This dissertation describes the investigation of molecular approaches to DNA computing. The feasibility of encoding a bit (0 or 1) of information for DNA-based computations at the single nucleotide level was studied, particularly with regard to the efficiency and specificity of hybridization discrimination. Both gold and glass surfaces, with addressed arrays of 32 oligonucleotides, were employed with similar hybridization results. Although single-base discrimination may be achieved in the system, it is at the cost of a severe decrease in the efficiency of hybridization to perfectly matched sequences. This compromises the utility of single nucleotide encoding for DNA computing applications in the absence of some additional mechanism for increasing specificity. Several methods are suggested including a multiple-base encoding strategy. The multiple-base encoding strategy was employed to develop a prototype DNA computer. The approach was demonstrated by solving a small example of the Satisfiability (SAT) problem, an NP-complete problem in Boolean logic. 16 distinct DNA oligonucleotides, encoding all candidate solutions to the 4-variable-4-clause-3-SAT problem, were immobilized on a gold surface in the non-addressed format. Four cycles of MARK (hybridization), DESTROY (enzymatic destruction) and UNMARK (denaturation) were performed, which identified and eliminated members of the set which were not solutions to the problem. Determination of the answer was accomplished in the READOUT (sequence identification) operation by PCR amplification of the remaining molecules and hybridization to an addressed array. Four answers were determined and the S/N ratio between correct and incorrect solutions ranged from 10 to 777, making discrimination between correct and incorrect solutions to the problem straightforward. Additionally, studies of enzymatic manipulations of DNA molecules on surfaces suggested the use of E. coli Exonuclease I (Exo I) and perhaps EarI in the DESTROY operation.